Day :
- Special Session on How acoustic emissions technology will impact microbiology
Session Introduction
Clair L. Hicks
University of Kentucky, USA
Title: How acoustic emissions technology will impact microbiology
Time : 12:05-13:05
Biography:
Clair L Hicks has completed his PhD at University of Wisconsin, USA in 1974 and began his research and teaching career at University of Kentucky. He has served as Commodity Leader for the Food Science faculty and as their Director of Undergraduate Studies. He has published more than 73 refereed papers and 127 abstracts. He has served as a Board Member for the American Dairy Science Association and for the Institute of Food Technologist Bluegrass Section. He has also served as Board Member and Chair of the Editorial Board for the Journal of Dairy Science.
Abstract:
Acoustic emissions (AE) generated by three strains of Escherichia coli (5024-parent, 8279-mutant and 8279-random/unrelated) and Lactococcus lactis ssp. lactis C2 infected with three bacteriophages (c2, sk1, and ml3; infected at 90 min) will be overviewed to demonstrate the sensitivity and accuracy of this technique. An acoustic sensor with an optimum range between 35-100 kHz was inserted into the growth vessel to capture AE data. E. coli were used to determine if the AE technique could be used to differentiate closely related strains while L. lactis bacteriophage infections were used to determine if AE techniques could track host stress and infection cycles. AE data was collected for Absolute Energy (ABE), Peak Frequency (PF) and Centroid Frequency (CF). When the CF for the parent and mutant E. coli strains were analyzed at 5 kHz intervals 14 areas within the frequency pattern were significantly different and almost all patterns were different for the 8279 strain suggesting that AE could be a powerful tool in identifying microorganism strains that were closely related. When the L. lactis host was infected with bacteriophage ml3, sk1 or c2, sufficient differences in ABE, CF and PF occurred, allowing for the identification of the bacteriophage and tracking of the infection cycles. The AE data suggested that bacteriophage sk1 and c2 caused greater stress on the host, lactis C2, than bacteriophage ml3. After infection, when the bacteriophage replication began, the AE information being emitted increased significantly from that of normal host activity.
- Track 1: Food Microbiology Track 2: Microbiology of Fermented Foods and Beverages Track 3: Food Borne Pathogens, Diseases & Public Health Track 4: Microbial Ecology of Foods Track 6: Single Cell Protein Track 7: Microbiology and Biotechnological Exploitation Track 9: Food Mycology
Session Introduction
Shashi Sharma
US Food and Drug Administration, USA
Title: Cleavage sensitive antibody for the detection of type A botulinum neurotoxin by biolayer interferometry
Time : 14:05-14:30
Biography:
Shashi K Sharma currently serves as Team Leader of Special Pathogens and Select Agents (SPSA) at the Division of Microbiology in the Office of Regulatory Science. He oversees a group of researchers and support scientists engaged in a multi-parameter research program to develop and apply microbiological and molecular genetic strategies for detecting and identifying select agent and bacterial foodborne pathogens. His early work on the development of monoclonal antibodies and immunodiagnostics of HIV and Typhoid including a unique detection system based on liposomal technology for Syphilis antigen. Dr. Sharma received his Ph.D. in Microbiology from University of Bhopal, India in 1992. In 1994, he joined the Department of Biochemistry, University of Massachusetts Dartmouth, where he worked on the structure and function of Clostridium botulinum neurotoxins. Dr. Sharma came to the Food and Drug Administration in 2002 and has since carried out numerous experiments relating to the detection and identification of select agents and foodborne pathogens. He is a member of the American Society for Microbiology and has co-authored more than 50 publications and book chapters on detection and identification of select agents such as Botulinum, Ricin, Bacillius anthracis and Francisella tularensis. His current research focuses on the development and validation of an effective and sensitive detection system for Clostridium botulinum toxins in foods. He has served in advisory role to the US government agencies on select agents assay development and a founding executive board member of Institute of Advance Science, Dartmouth, MA.
Abstract:
Background: Contemporary technologies and assay methods are being explored continuously for rapid and sensitive detection of biologically active BoNTs in food and environmental samples to facilitate enhanced public health response. Previously, FRET based substrates were used to detect the presence of active BoNTs in samples. However their efficacy to screen food samples and identify serotypes associated with unknown samples is largely limited. In this work, we have evaluated the application of cleavage sensitive monoclonal antibodies (CSM) to detect enzymatically active BoNT Type A using Bio-Layer Interferometry (BLI). CSM are developed to recognize only the neo-epitopes that are generated after the cleavage of target substrates by BoNTs. Methods: BLI platform (Pall Fortebio Octet) was used to evaluate the ability of type-A CSM (CSM-A) to specifically detect the catalytic action of BoNT/A, by measuring its binding to the BoNT/A cleaved fragment of SNAP-25. BLI is a powerful, versatile, rapid and label-free biosensor tool for characterizing the real-time kinetics of binding interactions between ligands and analytes. Full-length His-SNAP-25 (ligand) was coated on the surface of the sensor tips. Toxin and CSM-A (analyte) were placed in 96-well polypropylene plates. SNAP-25 coated sensor tips were then exposed to the wells containing toxin at different concentration (0, 1, 3, 6 and 12.5 ng/ml) and for varying incubation times (30-90 minutes). The loaded tips were then incubated with CSM-A, and the binding activity of the CSM-A was studied. Results: The CSM-A based BLI assay demonstrated concentration and activity dependent binding characteristics and can reliably report BoNT/A enzymatic activity. Notably it required less than 5 hours for sensitive and specific detection of BoNT/A. The preliminary studies showed that CSM-A based BLI assay was able to detect active toxins dilutions in the range of 1 ng/ml (in buffer). Conclusions: CSM show potential to rapidly detect biologically active toxins on the BLI platform. With the development of cleavage sensitive monoclonal antibodies specific to other serotypes of BoNTs, high throughput serotype specific rapid screening assays can be developed. The ability of this platform to detect and quantify the toxin in food samples is currently being evaluated.
Scott Crerar
Food Standards Australia, Australia
Title: Challenges associated with hepatitis A virus in berries and berry- products: A food regulators perspective
Time : 14:30-14:55
Biography:
Scott Crerar is a General Manager of Risk and Regulatory Assessment at Food Standards Australia New Zealand (FSANZ). He has oversight of chemical and microbiological risk assessment and social science and regulatory impact assessments. He has previously led the Strategic Science, International and Surveillance Section and managed the development and implementation of the FSANZ Science Strategy and international work including APEC activities. He has worked in food safety and regulation for many years and undertaken consultancies in food safety and food quality for the FAO and WHO, as well as working throughout the Asia-Pacific region.
Abstract:
Hepatitis A virus (HAV) outbreaks associated with ready to eat berries and berry products have emerged globally as a public health threat in recent years. Several consecutive multi-country food borne HAV outbreaks were experienced in Europe from 2012-2014, Australia and New Zealand in 2015 and Canada in 2016. Globally, berry growing and processing areas and their associated supply chains are diverse and complex, making traceability and certification of good agricultural and good manufacturing processes a complex task for industry suppliers and food safety regulators. In this context, traditional risk assessments are problematic due to limitations in data on prevalence in berries and subsequent assessment of exposure. For ready to eat fresh or frozen products, there are currently no effective, realistic and validated risk management options to eliminate viral contamination prior to consumption without changing the normally desired characteristics of the food. Testing for HAV in berries is problematic and batch testing is not a reliable indicator of the relative safety of the berries or berry product. Testing may be appropriate for outbreak investigations or in circumstances where there is a strong epidemiological suspicion of contamination. Data from the outbreak of HAV associated with berries that occurred in Australia in 2015 will be presented. The challenges associated with control, particularly in obtaining assurances around good agricultural and hygienic practices were evident as a result of this outbreak. As these are critical to the risk management of ready to eat berries, food safety regulators should have mechanisms in place to ensure compliance with these practices.
Catherine Rees
University of Nottingham, UK
Title: Detection of viable Mycobacteria in milk and milk products – implications for the dairy industry and human health
Time : 14:55-15:20
Biography:
Original training was in Biochemistry and Genetics, but the focus of my current research is on the application of molecular techniques to study various aspects of applied microbiology. Long term interest in the development of phage-based methods of bacterial detection (specifically Mycobacteria). Recent research focus has been on the development of rapid, non-recombinant, phage-based tests for the detection of mycobacterial pathogens for the food and agriculture sectors.
Abstract:
The introduction of routine pasteurisation of milk and a TB eradication program resulted in a dramatic reduction in the number of cases of human TB in the UK, from more than 50,000 cases per annum in the 1940’s to less than 50 cases of human Mycobacterium bovis infections being reported per annumn since the 1990’s. However there are many reports of viable Mycobacterium paratuberculosis (MAP) being detected in retail milk and milk products, indicating that this group of bacteria can survive commercial pasteurisation. Although not a recognised zoonotic organism, an association has been established between MAP and the development of Crohn’s disease, and regulatory bodies have advised that MAP should be eradicated from the food chain on a precautionary principle. We have developed a method to rapidly and sensitively detect pathogenic mycobacteria in milk and have showed it can be used to detect viable MAP in milk products, including powdered infant formula. We have been working with raw milk cheese producers to develop methods to detect M. bovis in raw milk to ensure the safety of their products. Given increasing consumer interest in the consumption of raw milk, and the resurgence of bovine TB in the UK, these methods will provide new ways to allow quality assurance tests to be performed. I will review the work that we have carried out and also discuss how this technique can also be used to develop new approaches to eradicate these endemic diseases from diary cattle to further improve food safety.
Leen Van Campenhout
University of Leuven, Belgium
Title: Microbial quality and food safety of edible insects as a novel and sustainable food matrix
Time : 15:20-15:45
Biography:
Leen Van Campenhout has completed her PhD in 2000 at the University of Leuven (KU Leuven), Belgium. From 1999 to 2004, she was R&D Manager in Enzymology & Microbiology in an international feed additive company. Then she became Professor at the Katholieke Hogeschool Kempen and at the University of Leuven. Her expertise is situated in food microbiology. Her main research topics include (i) (mild) conservation of food using e.g. Modified Atmosphere Packaging, (ii) the microbiology of new food matrices, such as insects, and (iii) the implementation of new technologies, e.g. metagenomics, in the food industry.
Abstract:
Traditional animal protein sources will not be able to supply the growing world population. Edible insects are put forward as a sustainable alternative. While the novel food regulation is currently being revised, in Belgium the Federal Agency for the Safety of the Food Chain (FASFC) has already authorized the marketing of ten insect species. A complete rearing and processing chain is now establishing in Belgium and other countries. Yet the knowledge on the microbial status and food safety of insects during rearing, processing and storage is very scarce. Therefore, we conduct several research projects aiming at investigating the microbial community of edible insects “from farm to fork”. An overview of the results obtained will be presented. As to the rearing phase, key aspects currently under investigation are (i) the microbial dynamics during industrial rearing of mealworm larvae (Tenebrio molitor), house crickets (Acheta domesticus) and grasshoppers (Locusta migratoria), (ii) the impact of specific practices during rearing on the microbial quality, such as starving and rinsing before killing, and (iii) transmission of pathogens from the substrate to the insects. Also a survey is being conducted on the microbial quality of different batches obtained from several industrial rearing facilities, using both culture-dependent analyses as well as culture-independent metagenomics. As to processing of insects, the impact of processing steps on the insect microbiota is determined. Processing steps currently under investigation include cooling, blanching, freeze-drying and microwave drying. Finally, shelf life experiments with a number of foods containing insects will be illustrated.
Santiago Benito
Madrid Polytechnic University, Spain
Title: Lachancea thermotolerans and Saccharomyces cerevisiae sequential inoculated fermentation influences in wine quality and acidic composition of Spanish wine
Time : 15:45-16:10
Biography:
Santiago Benito is a University Professor in the Madrid Polytechnic University. He is the Director of the Madrid University Experimental Winery, a scientific center. He has published more than 25 papers in reputed journals and has been serving as an Editorial Board Member of repute.
Abstract:
The scientific work researched the influence of Lachancea thermotolerans on low-acidity Spanish grape must from the south of Spain. Combined fermentations between Lachancea thermotolerans and Saccharomyces cerevisiae were compared to single control fermentation by S. cerevisiae. The results showed important differences in various parameters such as acidity, sensorial parameters, non-volatile and volatile compounds. The studied Spanish wine quality increased due to L. thermotolerans acidification ability. The acidification produced a L-lactic acid increase of 3.18 g/L and a decrease of 0.22 in pH compared to the studied control performed by S. cerevisiae.
Louay Labban
A’Sharqiyah University, Oman
Title: The implications of mycotoxins contamination on Omani food chain
Time : 16:25-16:50
Biography:
Louay Labban is currently a Professor of Nutrition and Dietetics at A’Sharqiyah University in Sultante of Oman. Earlier he taught for 6 years at Kalamoon University in Syria. He taught several courses related to nutrition and dietetics. He has also served as Vice Dean of Faculty of Health Sciences at the same university. Before joining Kalamoon University, he taught several courses in American Universities and also worked for different pharmaceutical companies in the United States for many years and he was responsible for studying the effect of newly developed medication on the nutritional status of volunteered patients and he also studied the drug-nutrient interaction for these medications. He has published several papers in regarding nutritional intervention in Diabetes Mellitus management. He has received his Bachelor degree from Damascus University in Syria, Master degree from University of Newcastle upon Tyne in England and his Doctorate degree from La Salle University in the United States.
Abstract:
Mycotoxins are group of fungal toxins that are widespread in agricultural commodities and food. The most notorious toxin of this group is Aflatoxin. It is produced by Aspergillus fungus and can result in major economic losses and can negatively affect animal and human health by causing both acute and chronic toxicity in animals and humans including acute liver damage, liver cirrhosis and liver cancers. Oman is a major importer of different agriculture commodities such as cereals, nuts, dried fruit, spices, oil seeds, dried peas, spices, beans and fruit. As Oman has a subtropical climate, food and feed commodities are susceptible to contamination and the food chain can be affected by poor storage of these products. In order to prevent the economic loss and the negative impact on health, Aflatoxin has to be detected in food chain. Some analytical techniques such as thin-layer chromatography (TLC), high performance liquid chromatography (HPLC), two-dimensional thin layer chromatography and enzyme-linked immunosorbent assay (ELISA) have been available for the qualitative and quantitative analysis of AFs. Although prevention is the best control strategy, it is not always possible to prevent all mycotoxin contamination. To control the risks associated with AF contamination, Hazard Analysis and Critical Control Point (HACCP) approach can be used. This approach involves strategies for prevention, control, good manufacturing practices and quality control at all stages of production from the field to the final consumer. Cheap and environmentally sustainable methods that can be applied pre or post-harvest to reduce the contamination of AFs are available. These methods include proper irrigation, choice of genetically resistant crop strains and bio-pesticide management which involves using a non-aflatoxigenic strain of Aspergillus that competitively excludes toxic strains. Other methods include sorting and disposal of visibly moldy or damaged seeds, reducing the bioavailability of aflatoxins using clay and chemo-protection.
Jean-Christophe Meile
CIRAD – UMR Qualisud – Réunion, France
Title: Food traceability : How microbial ecology can help
Time : 16:50-17:15
Biography:
Jean-Christophe Meile has completed his PhD in molecular genetics in 2006 from Paris-Orsay University and postdoctoral studies from CNRS at University of Toulouse (France). In 2011, he joined the Qualisud (Integrated Approach to Food Quality) research unit of Cirad. His research activities focus on the development of molecular methods in food microbiology for food safety and traceability. Based in the french Reunion island since 2015, he microbial ecology of tropical food. He has published about 15 papers in peer-reviewed journals.
Abstract:
The Food Law (European regulation CE No.178/2002), applied since january 2005, imposes to all food processing companies of the European Union (EU) to keep consumers informed about the nature of the product and any sanitary problems. Moreover, it imposes the traceability of foodstuffs at all steps of the food production. However, there is, at the moment, no real analytical tool for food traceability allowing authentication of the product origin or the farming type in a simple, fast and inexpensive way. The skin of fresh foods (vegetables, fruits) carries microbial communities that vary according to environmental parameters (soil, plant variety and physiology ...). Previous works showed that there is a link between the geographical origin of food and the structure of the microbial communities of fish, fruits and marine salts. This was performed using a method based on the extraction, PCR amplification and profiling of microbial DNA regions to study bacterial and fungal communities. Evidences suggest that there is a specific signature of food origin at the microbial ecology level that can be determined by molecular techniques. Appropriate statistical methods applied to molecular signatures comparison can help reveal significant differences between samples. From these data could be extracted markers that are specific of a region or a mode of production. For example, recent work using this approach showed that, it was possible to distinguish between organic from conventional fruits. Following the presentation of several studies their potential use for fraud detection and authentication controls in food will be discussed.
Tejpal Dhewa
Central University of Haryana, India
Title: Exploration of antibacterial and biopreservation potential of lactic acid bacteria isolated from traditional fermented foods of India
Time : 17:15-17:40
Biography:
Tejpal Dhewa is currently working as Assistant Professor in the Department of Nutrition Biology, Central University of Haryana. Earlier, he taught in the Department of Microbiology, Bhaskarcharya College of Applied Sciences (University of Delhi), New Delhi and Dolphin (PG) Institute of Biomedical and Natural Sciences, Dehradun. He received his master degree in Microbiology from University of Rajasthan, Jaipur and earned his doctoral degree in Microbiology from Bundelkhand University, Jhansi. He is involved in teaching PG students with special focus on food microbiology, medical microbiology and industrial microbiology. He has guided several M.Sc. students in DIBNS. He has executed research projects supported by Mascoma Corporation (USA) and University of Delhi (DU), Delhi. Currently he is Principal Investigator (PI) of DU Innovation Project on development of a real time biosensor to detect microorganisms in food and agricultural products. Recently he has completed student research project on evaluation of probiotics. He developed two antimicrobial formulation against methicillin and vancomycin resistant Staphylococcus aureus and filed two national patents. He also developed freeze dried synbiotic formulation for extension of shelf life of probiotic products. He has published more than 25 papers, 10 presentations in National and International Seminars and Conferences, 1 book, 3 monographs, 3 popular articles, and several book chapters to his credit.
Abstract:
Lactic acid bacteria (LAB) are generally regarded as safe bacteria and have significant role in human daily life. These bacteria produce certain antimicrobial agents like organic acids, diacetyl, hydrogen peroxide which helps to extend the shelf life of various food products. The aim of this study was to screen the antibacterial activity of LAB isolated from traditional fermented foods of India (especially rural regions) against the most common food borne (indicator) pathogens. The antagonistic potential of these isolates against Escherichia coli, Staphylococcus aureus, Salmonella species and Bacillus cereus were tested using agar well diffusion method. Out of 30 lactic acid bacteria isolates five isolates (i.e., LAB1, LAB2, LAB3, LAB4 and LAB5) were effective against all selected indicator pathogens. Amongst the five isolates, LAB3 exhibited the highest antibacterial activity in terms of zone of inhibition (>18±1.5 mm) and least activity was shown by isolate LAB2 (>10±1.8 mm). The degree of antimicrobial potential among the isolates was in the order of LAB3>LAB1>LAB4>LAB5>LAB2. Overall, the isolated LAB exhibited significant inhibitory effects against wide range of food borne pathogens. Although, the spectrum of inhibition was varied for the isolates examined but the above finding explore their potential application as a natural biopreservatives (i.e., bacteriocins) due to inhibiting the growth of pathogenic and food spoiling bacteria, maintaining the nutritive quality, flavor enhancer and extending the shelf life in wide range of food products (such studies are under progress in laboratory). Moreover, the characterization of antibacterial agents helps in the improvement of food product safety.
Herbert W Ockerman
The Ohio State Univeristy, USA
Title: Employee Training-Food Microbiology
Time : 17:40-18:05
Biography:
I am a professor at the Ohio State University. My research interests include meat science, biochemistry, microbiology and food safety. I am also involved in various international outreach programs to expand international cooperation in research and education. My scientific work, which includes more than 2000 papers, articles and book chapters, has been published in numerous journals. I have presented at more than 400 national and international conferences and speaking engagements. My professional affiliations include memberships to 30 different societies, including the American Meat Science Association and Institute of Food Technologists.
Abstract:
The best food safety program is useless unless the employees that handle the food are convinced that it is important. Convincing them that something they cannot see is important to food safety is difficult and at best short term. The dictum that “a picture is worth a thousand words” can be effective in communicating the importance of food safety and making the invisible visible. This presentation is designed as an employee training program for a meat environment, but the approach is just as effective for all food areas and it works best when all employees are involved. The objective of the training is to reinforce the critical nature of food safety and sanitation to the well-being of consumers and to the success of the food industry.
Siobhan Sue Reilly
Log10 LLC, USA
Title: Environmental microbiota in animal and food production establishments: Controlled change from bad to good
Time : 14:55-15:20
Biography:
Siobhan Sue Reilly is the President and CEO of Log10®, LLC in Ponca City, USA. She has received degrees in Food Science from the University of Florida (BS) and MS and PhD from Oklahoma State University. At Oklahoma State she has worked in the laboratory of Dr. Stanley Gilliland, a preeminent probiotic researcher and had research and extension appointments at Oklahoma State University. In 2003, she founded FoodProtech®, a food safety and quality testing and consulting company and served as its President and CEO until 2013 when she founded Log10®.
Abstract:
Almost all animal and food manufacturing establishments have a growing population of bad bacteria resistant to antibiotics and powerful sanitizers. Listeria monocytogenes, Salmonella spp., Clostridium spp., STEC E. coli, Campylobacter spp., and Staphylococcus spp., have entered our food supply, challenged our medical professionals and resulted in extreme cases of disease. The overuse of antibiotics in animal agriculture has resulted in emergence of pathogenic microorganisms now dangerously resistant to many, if not all, available antibiotics. Some governmental agencies that regulate antibiotics use have begun to make changes in the use of sub-therapeutic antibiotics. These changes have altered the animal’s microbiota and subsequent environmental flora thus enhancing the pathogenic bacteria’s ability to flourish. These pathogens are making their way through the food supply to us. The use of sanitizers influences the environmental microbial population even more by increasing the pathogens resistance to these previously lethal chemicals. We propose a solution for animal and food production that may alleviate some of these problems i.e., replace the current existing environmental microflora with known groups of microorganisms that are considered safe for food use and are antagonistic to specific pathogens. This paper presents a focused application of specially formulated probiotic products for use in animal and food processing and validates their efficacy against Salmonella spp., Clostridium spp., and Listeria monocytogenes.
- Special Session on Microbial safety of fresh produce needs implementation of a risk-based management approach
Session Introduction
Shalini Sehgal
University of Delhi, India
Title: Microbial safety of fresh produce needs implementation of a risk-based management approach
Time : 10:00 - 10:45
Biography:
Shalini Sehgal is working as the Vice Principal and an Associate Professor in the Department of Food Technology, Bhaskaracharya College of Applied Sciences of University of Delhi, India. She has 18 years of experience in the field of education and has been associated with various academic and research projects. She has completed her MSc and Doctorate in Dairy Microbiology from National Dairy Research Institute, India. Her area of interest is food safety and she is trained in HACCP implementation, IS 22000: Food safety management system and food safety & food hygiene. She also has expertise in container integrity and undergone training by USFDA at Alameda Lab, California, USA. She has worked as National Food Safety Consultant with WHO and also undertaken projects on safety aspects of street foods and fresh produce and probiotics. She has authored two books and 12 chapters on different areas of food microbiology and food safety. She has published her research work in journals of repute.
Abstract:
Fresh fruits and vegetables are important to the health and well being of the consumer. Global trade in fruits and vegetables and changing horticultural practices have enabled the year-round abundance to be possible, as well as adding new varieties of fresh produce to the market However, over the last several years, the detection of outbreaks of food borne illness associated with both domestic and imported fresh fruits and vegetables have increased. Fruits and vegetables are widely exposed to microbial contamination through contact with soil, dust and water and by handling at harvest or during postharvest processing. They therefore harbor a diverse range of microorganisms including plant and human pathogens. Currently no data is available about the microbial hazards associated with fresh produce in India. In the present study, 200 samples of fresh vegetables (150) and fruits (50) were collected from both local and retail markets from the southern part of Delhi, the capital of India. Then, the total microbial load, yeasts and molds on their surface were estimated. Majority of samples were found to be contaminated. The bacterial counts were found to be much higher than the Yeast and Molds counts. Presence of coliforms was also detected. Then, to eliminate the surface microbial load, various types of antimicrobial dips in varying concentration were used. Among, all the three types of antimicrobial dips tested, the most effective was found to be citric acid at 1% concentration. In this study, an initial survey of 100 retail outlets was done to assess the prevalent food safety practices of the food handlers in the various retail outlets. The findings revealed that the handling practices of the food handlers and their awareness about food safety also plays a critical role in microbial safety of fresh produce. Thus, the safety and quality of fresh produce requires implementation of a risk-based management system approach through all stages of production, distribution, storage, transportation and marketing of food products in the complete food chain.
- Track 5: Risk Assessment and Risk Management Track 8: Uses of Microorganisms in Food Travk 10: Predictive Microbiology Track 11: Microbial Aspects of Food Spoilage and Quality Track 12: Current & Future Aspects of Probiotics
Session Introduction
Santiago Benito
Madrid Polytechnic University, Spain
Title: Modern trends in Schizosaccharomyces use for winemaking
Time : 10: 35 -11:00
Biography:
Santiago Benito is a University Professor in the Madrid Polytechnic University. He is the Director of the Madrid University Experimental Winery, a scientific center. He has published more than 25 papers in reputed journals and has been serving as an Editorial Board Member of repute.
Abstract:
Several scientifics are studying the winemaking potential of non-Saccharomyces yeasts. For example, yeasts from the genus Schizosaccharomyces traditionally have been studied from a winemaking point of view due to its rapid malic acid deacidification, by converting malic acid to ethanol and CO2. Nevertheless, Schizosaccharomyces genus possesses several remarkable metabolic properties that may be useful in modern quality winemaking, including a malic dehydrogenase activity, high autolytic polysaccharides release, ability of gluconic acid reduction, urease activity, elevated production of pyruvic acid and colour improvement, as well as low production of biogenic amines and ethyl carbamate.
Muhammad Riaz
Sejong University, Seoul-South Korea
Title: Effective utilization of microbial cells for decontamination of Aflatoxin M1 in milk
Time : 11:15 - 11:40
Biography:
Muhammad Riaz is the Research Assistant Professor at the Department of Food Science and Technology, Sejong University, Seoul-South Korea. He completed his B.Sc. (Hons.) and M.Sc. (Hons.) Food Technology from National Institute of Food Science and Technology, University of Agriculture, Faisalabad-Pakistan. He holds PhD in Biotechnology from National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad. He worked as an Assistant Professor at the Institute of Food Science and Nutrition, Bahauddin Zakariya University, Multan-Pakistan. His has 12 years, professional, research and teaching experience. He has produced 10 MPhil students and 3 students of PhD are working on food safety issues under his supervision. He has published plenty of research articles in journals of International Repute. Dr. Riaz has won many grants from various donor agencies and working as PI and Co-PI of projects on food safety issues. He is working as Associated Editor in International Journal of Food and Allied Sciences. He has been awarded Research Productivity Awards in 2011 and 2012 from Pakistan Council of Science and Technology. Currently he is working on the decontamination strategies of aflatoxin M1 in Milk, and assessment of microbial and other contaminants including heavy metals, aflatoxins, E. Coli, Coliforms and Salmonella in food and food products.
Abstract:
Aflatoxin M1 (AFM1) is one of the category 1 carcinogenic compound found in milk. AFM1 is usually found in milk from animals fed on aflatoxin B1 (AFB1) contaminated fodder. AFB1 is converted in AFM1 in liver and get absorbed into the milk during biosynthesis. AFM1 is considered as one of the potential human carcinogen, cytotoxin, teratogenic and genotoxic agent. Various strategies including, microwave heating, pasteurization, sterilization, binding with clay and microbial cells have been adopted to degrade, decontaminate and removal of this toxic compound from milk. However, decontamination of AFM1 by binding it with microbial cell culture and then removal by centrifugation is considered as the most effective. In the current study three strains of lactic acid bacteria, a yeast strain of Saccharomyces cereveisae and a mixture of both were used to evaluate their binding potentials for AFM1. Two different concentrations of AFM1 0.05 and 0.1 µg/l were spiked in milk samples in the presence of various concentrations and their combinations of microbial cells. The concentration of AFM1 and microbes were found to significantly affect the binding potentials of microbes. Saccharomyces cereveisae, lactobacillus helveticus and the mixture of microbes at the concentration of 1010 cfu/ml were found to be most effective for binding of AFM1. The stability of the AFM1-microbial-cell complex revealed safe usage of microbes for the reduction of AFM1 levels up to harmless limits.
Guzin Kaban
University of Atatürk, Turkey
Title: Effects of Lactobacillus sakei S15 and Staphylococcus xylosus GM92 on volatile compounds and sensory characteristics of heat-treated sucuk
Time : 11:40-12:05
Biography:
Guzin Kaban has received her PhD degree from University of Ataturk in 2007. She is currently a Professor in Department of Food Engineering at the same university. She has more than 30 articles published in academic journals scanned by SCI and SCI-Expanded. She has been working on traditional Turkish meat products and is a Co-Author of six chapters in four published books. Her studies have predominantly focused on the lactic acid bacteria and coagulase negative staphylococci, as well as volatile compounds of traditional Turkish meat products. She is also a Member of Advisory Commission on Meat Products, Republic of Turkey, Ministry of Food, Agriculture and Animal Husbandry.
Abstract:
In this research, effects of Lactobacillus sakei S15 and Staphylococcus xylosus GM92, isolated from sucuk, a traditional Turkish dry-fermented sausage, on volatile compounds and sensory characteristics of heat-treated sucuk (semi-dry fermented sausage) were investigated. Three different heat-treated sucuk groups (control, L. sakei S15 and L. sakei S15+S. xylosus GM92) were produced under controlled conditions. The profile of volatile compounds were analyzed by gas chromatography/mass spectrometry (GC-MS) using a solid phase microextraction (SPME). Samples were taken from the batters, after fermentation (48 hours at 22 °C), heat-treatment (inner temperature at 68 °C) and drying stages. Sensory analysis was carried out on the final product. A total of 66 compounds (9 sulfur compounds, 3 alcohols, 4 ketones, 7 aliphatic hydrocarbons, 6 esters, 8 aldehydes, 6 aromatic hydrocarbons, 1 furan and 22 terpenes) were identified from sucuk samples. Use of L. sakei S15 or L. sakei S15+S. xylosus GM92 showed very significant or significant effects on 14 volatile compounds. Some volatile compounds occurred during the heat treatment stage. Significant increases were observed in the amounts of volatile compounds in drying stage. L. sakei S15+S. xylosus GM92 showed a higher sensory score than the control and L. sakei S15 in terms of color.
Abdel Moneim E Sulieman
University of Hail, KSA
Title: Impact of some essential oils on inhibition of aflatoxin production by Aspergillus flavus
Time : 12:05-12:30
Biography:
Abdel Moneim has been awarded his PhD in 2001 and pursued a postdoctoral fellowship at University of Kobe, Japan. He is expert in “Food Science and Technology, his main concern is food microbiology. He has authored a large number of articles in reputed journals and has been invited to different international conferences. He published many books in the area of food science and technology. He is a member of many national and international academic associations.
Abstract:
The present study aimed to investigate the effects of some essential oils on inhibiting fungal growth of A. flavus and aflatoxin production. Clove oil was found as the best among six different oils tested against the radial growth at the concentration of 0.05 mL/100 ml. However, other oils were also significantly better than the control except the pumpkin oil. Although pumpkin oil was slightly effective than the control at its higher concentration (0.05 ml per 100 ml), but it was not effective at its lower concentrations (0.00, 0.01 and 0.03 ml/100 ml). All tested oils were significantly better than the control in suppression of mycelia growth and highest suppression was accomplished by clove oil at 0.05 ml/100 ml concentration, while, pumpkin oil was not effective. Although pumpkin oil was slightly better than the control at its higher concentration (0.05 ml/100 ml), it was not effective at its lower concentration (0.00, 0.01 and 0.03 ml/100 ml). Spore germination was also affected by the oils tested. Clove oil gave complete inhibition at its higher concentration followed by Cummin, Rehan, Garlic and Desert date, while Pumpkin oil was the least one. Aflatoxin production was highly affected by the essential oils tested. Clove and Cummin exhibited a complete inhibition followed by Rehan, Garlic and Desert date while Pumpkin oil was not effective.
Cauré B. Portugal
University of Sao Paulo, Brazil
Title: achaça: a brief scenario of spontaneous fermentation of the Brazilian distilled spirit
Time : 12:30-12:55
Biography:
Caure Barbosa Portugal has completed his PhD in Enological Microbiology at the University of La Rioja, Spain (2012), following his Postdoctoral studies in the College of Agriculture ‘Luiz de Queiroz’ (ESALQ, University of São Paulo) in Piracicaba, Brazil. He is currently responsible for fermentation microbiology researches in the Laboratory of Technology and Quality of Beverages of ESALQ. He has published papers regarding fermentation processes in wine, beer and cachaca, focused in spontaneous fermentations, non-conventional yeasts and microbial control of beverages.
Abstract:
Cachaca is the Brazilian distilled spirit, produced by fermentation of sugarcane juice and subsequent distillation. Some cachacas have a story to tell, showing an intimate relationship with the surrounding environment, regional heritage and traditional practices. The artisanal production mainly relies on spontaneous fermentation processes and includes different exogenous sources of microbial populations to the must with fermentative cycles that usually last 18–30 hours with high incidence of authochtonous yeasts. Non-Saccharomyces yeasts usually present low fermentative performance but uncontrolled growth of these microorganisms can lead to dangerous levels of undesirable or harmful compounds. In well-driven processes, these microorganisms may contribute to flavor, reflecting typical characteristics of the product. Although these approaches may give rise to cachacas with higher aromatic complexity, they can lead to sluggish and stuck fermentations and give way to early spoilage by undesirable microorganisms. Healthy spontaneous fermentations may provide higher diversity environments, enabling yeast species to mainly act as a cluster and propitiate a richer floral, fruity character. Besides, recent climate anomalies show direct correlation to musts with unusual low assimilable nitrogen contents, leading to early dominance and persistence of less demanding yeasts and overgrowth of bacterial communities. Such conditions also seem to have induced microenvironments with low species’ evenness and spoilage microorganism dominance. Our results have helped to better understand the role of the native microbiota and the impact of these players in the production of high quality cachacas, in addition to assist producers to adopt insightful agricultural, handling practices and strict control of technical guidelines.
Shalini Sehgal
University of Delhi, India
Title: Consumer awareness and evaluation of probiotic products sold in Indian market
Time : 14:00-14:25
Biography:
Shalini Sehgal is working as the Vice Principal and an Associate Professor in the Department of Food Technology, Bhaskaracharya College of Applied Sciences of University of Delhi, India. She has 18 years of experience in the field of education and has been associated with various academic and research projects. She has completed her MSc and Doctorate in Dairy Microbiology from National Dairy Research Institute, India. Her area of interest is food safety and she is trained in HACCP implementation, IS 22000: Food safety management system and food safety & food hygiene. She also has expertise in container integrity and undergone training by USFDA at Alameda Lab, California, USA. She has worked as National Food Safety Consultant with WHO and also undertaken projects on safety aspects of street foods and fresh produce and probiotics. She has authored two books and 12 chapters on different areas of food microbiology and food safety. She has published her research work in journals of repute.
Abstract:
Consumers are becoming more aware of functional foods and nutritional supplements and the potential role of these products in balanced diet and in ensuring good health. Probiotics are becoming increasingly popular as functional foods because of their health benefits. In coherence with the global scenario, the demand and supply for probiotics in India too is at a steep rise. The aim of this study was to assess the consumer awareness and perception about probiotics. The research design also evaluated the type of probiotic products being sold in the Delhi market, their current labeling and storage practices. The storage temperature is critical to the functionality of the probiotic products as inappropriate storage temperature at any step post manufacture may result in decline of the probiotic microorganisms. A cross sectional random population survey using questionnaire across NCR about the knowledge and perception of the Indian consumer (n=735) about probiotics was conducted. Majority of the consumers were not aware about the concept of probiotics and were not able to differentiate probiotics and fermented foods. The perceived barriers to purchase of probiotics included cost and availability. Onsite analysis of the probiotic products at the retail outlets (n=132 outlets) showed a storage temperature deviation as high as 22 °C which is detrimental to the viability of probiotic microorganisms and thereby the functionality of probiotics. The viable counts were found in range for majority of probiotic foods. The labeling practices of probiotic products (n=213) revealed that there is no mention of the species name and health claims by majority of the Indian brands although it is a must as per the guidelines down by ICMR-DBT, India. There is an urgent need of a regulatory regime governing the sale of probiotic products in the country.
Ahlam Badreldin El Shikieri
Taibah University, Saudi Arabia
Title: Uses of microorganisms in indigenous foods and their impact on human health
Time : 14:25-14:50
Biography:
Ahlam Badreldin El Shikieri has completed her PhD from Queen Margaret University and has an MBA from Leicester University, UK. She is a registered Consultant Nutritionist, a Certified Public Health Nutritionist and an Associate Professor currently working in Saudi Arabia as the Head of the Clinical Nutrition Department at Taibah University. She has served as an invited speaker at several workshops and conferences in Sudan, Saudi Arabia, Spain, Germany and Taiwan. She has supervised several research projects for students both at Master and PhD levels and acted as an External Examiner for postgraduate thesis. She undertook several researches focusing on assessing the nutritional status of cancer patients, children, malnourished hospitalized patients and many others related to public health nutrition. She is a Member of the Academy of Nutrition and Dietetics, British Nutrition Society, World Public Health Nutrition Association and others. She is a Reviewer for various journals including the Journal of Nutrition Education and Behavior and has acted as an author for more than 16 published research papers and newsletter articles.
Abstract:
One of the oldest forms of food preservation methods in the world is fermentation. Many countries use microorganisms to ferment indigenous foods for many reasons including increasing the shelf-life and enhancing the taste and texture thus enriching the human diet, avoiding losing raw materials, reducing cooking time, improving protein quality and carbohydrate digestibility as well as eliminating toxic and anti-nutritional factors such as cyanogenic glycosides. In the Asian continent, taking Indonesia as an example, fruit and vegetables, soybean, rice and cassava, pork, buffalo and mare milk are all being fermented using lactic, mould or alcoholic fermentation. Moreover, the African region is considered having the richest varieties of lactic acid fermented foods including cereals, legumes, tuber roots, milk, fish and meat. Sudan, one of these countries has around 60 fermented foods items. Long time ago and until now, special concentration is being put on the benefits of lactic acid bacteria (LAB) to human health; one of which is probiotics. The latter has important roles to play including lowering blood cholesterol levels, preventing and treating diarrhea and altering the immune system. It has been shown that LAB is associated with vitamins’ enrichment and has antioxidant and anti-inflammatory properties. The last properties are being associated with the protection against various diseases including hypertension, altered mood, depression and other chronic conditions. Several factors might contribute to the safety of fermented foods thus affecting the human health and need not be neglected. In this presentation, selected types of fermentation, fermented food products in selected countries and the health implication of the intake of fermented foods will be presented.
- Young Research Forum
Session Introduction
Adele Silbande
University of Antilles, Martinique
Title: Microbial quality of ice-stored tropical yellowfin tuna (Thnnus albacares) steaks and influence of vaccum and modified atmosphere packaging
Time : 14:50-15:10
Biography:
Adèle Silbande is a PhD student in Food Microbiology research at the university of Antilles in Martinique. She works on the post-mortem microbial ecosystems of tropical fishes, Thunnus albacares and Sciaenops ocellatus, and the impact on the quality of the products (ECOSYSP). This research is realized with the PARM (Pôle agroalimentaire régional de Martinique) and Ifremer/EM3B (Ecosystèmes microbiens et molecules marines pour les biotechnologies) laboratories under the supervision of Dr. Françoise LEROI. She will defend her thesis work on December 2016 with four published or submitted papers on the subject.
Abstract:
The objective of this work was to describe precisely the bacterial ecosystem of the yellowfin tuna flesh widely consumed in Martinique. In addition to the culture-dependent methods, a Next-Generation Sequencing platform (Illumina MiSeq) was used on the bacterial DNA of the tuna steaks stored in ice (AIR – 0°C), vacuum (VP – 4/8°C) and modified atmosphere packaging (MAP – 4/8°C) until their respective sensory rejection point. At these dates, several bacterial strains were isolated and then inoculated in sterile tuna flesh to characterize their spoiling potential (challenge test). The organoleptic rejection of AIR products was observed at day 13 when total bacterial counts equaled 106 - 107 cfu.g-1. No extension of shelf-life was provided by VP and MAP. According to the metagenomic analysis, Rhodanobacter terrae was the main species of the freshly caught tuna. At the sensory rejection time, Brochothrix thermosphacta and Pseudomonas spp. dominated the AIR samples while B. thermosphacta alone or a mix of B. thermosphacta, Enterobacteriaceae and lactic acid bacteria dominated the microbiota of MAP and VP products, respectively. Pseudomonas spp., Enterobacter spp. and Escherichia spp. were categorized as non- or lightly-spoiling bacteria by the sensory panel; B. thermosphacta and Carnobacterium spp. exhibited moderate effects and were characterized by butter/caramel odors; Hafnia paralvei and Serratia spp. were considered as strong spoilers with pyrrolidine-like odors. When species were co-inoculated (by pair), the association between B. thermosphacta and Carnobacterium spp. favored a stronger deterioration while the addition of Pseudomonas spp. or B. thermosphacta to H. paralvei inhibited the developpement of unpleasant odors.
Zahra S. Al-Kharousi
Sultan Qaboos Univrsity, Oman
Title: Ingesting antibiotic resistant bacteria along with fresh fruits and vegetables: What are the possible consequences?
Time : 15:10-15:30
Biography:
Zahra Sulaiman Al-Kharousi has completed her M.Sc. in 2011 in food science and nutrition, microbiology. Her specialization in Bachelor was medical laboratory science, microbiology. She is a lab supervisor in the department of food science and nutrition in college of Agricultural and Marine Sciences, Sultan Qaboos University, Oman. Now, she is conducting her Ph.D. study in food microbiology. Her research is about resistance of bacteria isolated from fruits and vegetables to antibiotics and disinfectants. She has 3 published papers. She has been known as an outstanding student and had a GPA of 4.0 on a 4.0 scale in her M.Sc.
Abstract:
If left untreated, the antibiotic-resistance problem might engage us in a difficult global war against tiny bacterial superbugs. Local efforts to address and manage this problem in various environments will eventually contribute to a better global tackling. Fresh fruits and vegetables can be heavily inhabited by bacteria that can act as a significant reservoir for antibiotic-resistance genes. This study was aimed to determine antibiotic-resistance of bacteria isolated from fresh produce. One hundred and five samples of fresh fruits and vegetables originated from different countries were used to isolate 3 groups of bacteria; Enterobacteriaceae (92 isolates), Enterococcus (31 isolates) and Staphylococcus aureus (3 isolates). Bacteria were identified by PCR and VITEK 2 system and many of them were opportunistic pathogens. Enterobacteriaceae bacteria were resistant to ampicillin (57.6%), cephalothin (42.4%), cefoxitin (26.1%), amoxicillin/clavulanic acid (19.6%), tetracycline (8.7%), nalidixic acid (5.4%), trimethoprim (5.4%), kanamycin (3.3%) and chloramphenicol (1.1%). Some isolates showed intermediate resistance to imipenem (3.3%) and ertapenem (1.1%). Resistance to cefoxitin indicated possible presence of Ambler class C (AmpC) β-lactamase and this was confirmed by a three-dimensional method in 22 isolates. Enterococcus bacteria were resistant to tetracycline (19.4%), erythromycin (9.7%) and chloramphenicol (3.2%). Intermediate resistance to ciprofloxacin (51.6%) and vancomycin (9.7%) was also found. S. aureus isolates were sensitive to all antibiotics tested. These results suggest that fresh produce may play an important role in disseminating antibiotic-resistant bacteria through the food chain. The possible consequences for ingestion of bacteria harboring antibiotic-resistant genes and their interaction with gut microbiota are also discussed here.
Syed Shahzad Shah
University of Tasmania, Australia
Title: Proteomic investigation on the effect of Tween 80 on growth of Lactobacillus casei (GCRL 163)
Time : 15:30-15:50
Biography:
Syed is currently in the final year of his PhD degree programme and is working on a project entitled “Probiotics survival in food products and retention of probiotics traits” based at the Food Safety Centre, Tasmanian Institute of Agriculture, University of Tasmania (Australia). He is winner of Endeavour Executive Award (2010) and completed a professional developed course at UTAS. Previously he has served in food industry sector for 8 years and as Lecturer in Food Technology at Allama Iqbal Open University Islamabad, Pakistan for 12 years. He has delivered nine research presentations at international conferences with publications in conference proceedings and one research paper publication.
Abstract:
Our aim was to investigate bacterial growth patterns and corresponding proteomes of Lactobacillus casei GCRL 163 (a cheddar cheese isolate) when cultured in modified MRS broths without glucose and acetate as carbon sources (fermenters operated anaerobically, pH 6.5). Growth in the basal medium (peptone, yeast extract and MRS salts) was minimal but was significantly improved by addition of 0.1% Tween 80 or 0.2% triammonium citrate, with highest growth rate and extent observed for citrate plus Tween 80. Stationary-phase cells were lysed then proteins trypsin digested and analysed by nanoLC-MS/MS. Differentially expressed proteins were identified using two-sided t-test (Perseus software version 1.5.031) with a permutation-based FDR of 0.05. In the presence of Tween 80, proteins related to carbohydrate metabolism (aldehyde-alcohol dehydrogenase and glucosamine-6-phosphate deaminase), tricarboxylic acid pathway (pyruvate carboxylase subunit B) and phosphotransferases were significantly upregulated whereas lipid-related metabolism proteins were significantly depressed compared to the basal medium control or citrate-grown cells. Tween 80 plus citrate cultures showed abundant levels of lipid-related metabolism proteins and ABC-type transporter substrate-binding proteins (absent in cells grown in Tween 80 alone) that facilitated co-metabolism of substrates, producing higher growth rates. Comparison across proteomes identified the involvement of several uncharacterised proteins related to MerR transcriptional regulation of growth during starvation and involvement of autoinducer-2 kinase in sensing or phosphotransport of normally poorly-utilized substrates. These data suggest that Lb. casei GCRL 163 can use Tween 80 and citrate alone or Tween 80 in combination with citrate as a carbon source, sustaining growth in absence of sugars.
Camila Andrea Bernal Castro
Universidad Nacional de Colombia, Colombia
Title: Advances in the development of tropical fruit drinks with inclusion of probiotics: In vitro
Time : 15:50-16:10
Biography:
Camila Andrea Bernal Castro completed her studies in industrial microbiology at the Pontificia Universidad Javeriana at the age of 23 years, she performanced for one year, as a young researcher in the laboratory of molecular parasitology at the Pontificia Universidad Javeriana. In 2013, she has published a paper in the journal Molecular Biology Reports: Molecular characterization of calcineurin B from the non-virulent Trypanosoma rangeli kinetoplastid indicates high gene conservation, she has attended congresses such as XX CONGRESS Latin American Federation of Parasitology and XV Congress of the Colombian Association of Parasitology and Tropical Medicine and the XI CONGRESS OF RESEARCH. In 2015, she presented an oral presentation at the National Meeting of Research and Development at the National University of Colombia named: Evaluation of properties that determine the shelf life of blackberry pulp including bee pollen. She is currently a master's student in food science and technology from the National University of Colombia in Bogota.
Abstract:
Functional foods in addition to providing a nutritive value, they must demonstrate a benefit to health by a physiological effect in reducing the risk of chronic diseases, in this category are the probiotics, which have traditionally been included in dairy products, a new trend is the inclusion of these microorganisms in fruit and vegetables . The inclusion of these microorganisms in vegetable matrices is a challenge for the industry of tropical fruits, however the fruits, vegetables and cereals have been shown to be substrates for cellular synthesis and production of lactic acid. Colombia is considered a primary producer of fruit, however there is high post-harvest losses, which requires the development of technological strategies. In vitro assays have been realized in this investigation about the pH as critical factor in the inclusion of probiotics, the development of a synthetic medium of fruit which was allowing to simulate the formulation of a nectar of fruit, curves of calibration of the growth of the microorganisms and the evaluation of the viability, the pH and the acidity in a nectar of mango with probióticos through a curve of growth. The aim of this work is to evaluate the viability of probiotics cultures of commercial type (Lactobacillus casei, Lactobacillus rhamnosus, Lactobacillus plantarum) in fruits as: Andean berry commonly known “Mora de Castilla” (Rubus glaucus Benth), Mango (Mangifera indicates), Papaya (Carica papaya) and Strawberry (Strawberry x ananassa L), for the production of juices and drinks.
Maria Neelam
Fatima Jinnah Women University, Pakistan
Title: Geospatial analysis of foliar rust diseases of wheat crop in Jhelum district (2010-2015)
Time : 16:25-16:50
Biography:
Maria Neelam is currently pursuing PhD in Environmental Sciences from Fatima Jinnah Women University, Pakistan. She has worked as Research Associate on Higher Education Comission funded project “Estimation of foliar and rust disease severity of rain fed wheat with GIS and remote sensing tools”.
Abstract:
This study was conducted to assess the past and present damaging effects of foliar rust diseases on wheat crop through Geographic information system tools. Wheat is the main cereal crop that is grown in Jhelum district on both irrigated and non-irrigated lands. Approximately, 200 diseases are reported on wheat crop in which 100 diseases are caused by pathogens and others are due to weeds and different parasites. Mostly rust diseases are air-borne and soil-borne. Foliar rust diseases; yellow/stripe rust, brown/leaf rust, powdery mildew and tan spot infect different parts of plants thus taking high toll of crop yield. This study focused on Jhelum district comparing the disease incidence data for last six years (2010-2015). Variation in Climatic Data including temperature, precipitation and humidity were analyzed for past six years because these variations are responsible for development of rust diseases. Mycotoxin risk assessment tool was used to assess the risk of Fusarium mycotoxins in wheat. Hotspot tool assesses clustering of high and low values thus used to identify hot and cold spots of rust diseases (leaf and stripe rust) in selected regions. Standard deviational ellipses showed the extent of variation of diseases exhibiting the directional trend for past six years. The results demonstrated in the form of graphs showed shift of diseases from one region to another depending on the climatic variation. In contrast to previous year, Leaf rust is more prevalent in Jhelum district. This study provided the information about spread and shift of leaf and stripe rust in Jhelum district through broad spectrum of geospatial analysis that result in real time visualization and predictive analysis. Leaf Rust is becoming more prevalent so the wheat varieties that are resistant against rust needs to be cultivated. Fungicides are also need to be used against development of mycotoxins that will ultimately lead to high yield of wheat crop.
Muhammad Adnan
Jiangnan University, China
Title: Foodborne microbes: An emerging dread
Time : 16:50-17:10
Biography:
Muhammad Adnan is currently pursuing PhD (Research Scholar) from Jiangnan University, China. He has completed his Postgraduate studies from University of Agriculture Faisalabad, Pakistan. He is the Research Student in State Key Lab of China in Food Science & Technology.
Abstract:
Food borne pathogens are the leading cause of illness and death in developing countries. The majority of foods borne diseases are caused by microbial pathogens such as viruses, bacteria and parasites. A common symptom of many Food borne diseases includes vomiting, diarrhea or bloody diarrhea, abdominal pain, fever and chills. Symptoms can range from mild to serious and can last from a few hours to several days. Food borne illnesses may lead to dehydration, hemolytic uremic syndrome (HUS) and other complications. Acute food borne illnesses may also lead to chronic or long lasting health problems. As Clostridium botulinum affect the nervous system, causing serious alarming symptoms such as food poisoning, headache, skin tingling, blurred vision, weakness, dizziness and paralysis. Food borne illnesses are infections or irritations of the gastrointestinal (GI) tract caused by food or beverages that contain harmful bacteria, parasites, viruses or chemicals. Anyone can get a food borne illness. However, some people are more likely to develop food borne illnesses than others including infants and children, pregnant women and their fetuses, older adults and people with weakened immune systems. Food and Drug Administration (FDA) gives information on 5 food borne illnesses risk factors: Improper hot and cold holding temperatures, inappropriate cooking temperatures, dirty or contaminated utensils and equipment, poor health and personal hygiene and food from unsafe sources. The only treatment needed for most food borne illnesses is replacing lost fluids and electrolytes to prevent dehydration. Food borne illnesses can be prevented by properly storing, cooking, cleaning and handling foods.
- Poster Presentation
Session Introduction
Maarit Maki
Natural Resources Institute Finland, Finland
Title: Antimicrobial and antioxidative properties of berry extracts
Biography:
Maarit Mäki has completed her PhD in Food Science from Helsinki University, Finland. She has been working as senior scientist since 1998 at Natural Resources Institute Finland.
Abstract:
Antioxidative and antimicrobial properties were tested from the samples of berries and juice press cake of blackcurrant (Ribes nigrum), chokeberries (Aronia melanocarpa/mitchurinii) and rose hips (Rosa rugosa), leaves of sea buckthorn (Hippophae rhamnoides), lingonberry (Vaccinium vitis-idaea), and bilberry (Vaccinium myrtillus) and stems and shrubs of bilberry. All samples were extracted with two different solvents: water and 50 % ethanol (aq) with solid/liquid ratio approximately 1:10. The most interesting samples, sea buckthorn leaf, bilberry shrub and blackcurrant juice press cake, were selected for further extraction studies with pressurized hot water extraction (PHWE). Antioxidant capacities were measured from all above extracts. The radical scavenging ability of the plant extracts was measured with the ABTS method and a lecithin liposome model was utilized to investigate the ability of the extracts to inhibit lipid oxidation. As a result, the highest antioxidant capacities were observed with the extracts from the leaves of sea buckthorn, lingonberry and bilberry, and bilberry shrubs. The 50 % ethanol extraction yielded to higher antioxidant capacities than the water extraction. The PHWE treatment yielded to slightly higher radical scavenging activity and slightly lower lipid oxidation inhibition activity than the 50 % ethanol extraction. Antimicrobial properties of the most interesting PHWE extracts were tested by agar diffusion tests. The extracts were tested on Pseudomonas fluorescens, Staphylococcus aureus, Yersinia enterocolitica, Yersinia pseudotuberculosis and Listeria monocytogenes. Except for blackcurrant juice press cake, PHWE extracts showed good antimicrobial effect on S. aureus, P. fluorescens, Y. enterocolitica and Y. pseudotuberculosis. No inhibition was detected on L. monocytogenes.
Maarit Maki
Natural Resources Institute Finland, Finland
Title: Antimicrobial and antioxidative properties of berry extracts
Biography:
Maarit Mäki has completed her PhD in Food Science from Helsinki University, Finland. She has been working as senior scientist since 1998 at Natural Resources Institute Finland.
Abstract:
Antioxidative and antimicrobial properties were tested from the samples of berries and juice press cake of blackcurrant (Ribes nigrum), chokeberries (Aronia melanocarpa/mitchurinii) and rose hips (Rosa rugosa), leaves of sea buckthorn (Hippophae rhamnoides), lingonberry (Vaccinium vitis-idaea), and bilberry (Vaccinium myrtillus) and stems and shrubs of bilberry. All samples were extracted with two different solvents: water and 50 % ethanol (aq) with solid/liquid ratio approximately 1:10. The most interesting samples, sea buckthorn leaf, bilberry shrub and blackcurrant juice press cake, were selected for further extraction studies with pressurized hot water extraction (PHWE). Antioxidant capacities were measured from all above extracts. The radical scavenging ability of the plant extracts was measured with the ABTS method and a lecithin liposome model was utilized to investigate the ability of the extracts to inhibit lipid oxidation. As a result, the highest antioxidant capacities were observed with the extracts from the leaves of sea buckthorn, lingonberry and bilberry, and bilberry shrubs. The 50 % ethanol extraction yielded to higher antioxidant capacities than the water extraction. The PHWE treatment yielded to slightly higher radical scavenging activity and slightly lower lipid oxidation inhibition activity than the 50 % ethanol extraction. Antimicrobial properties of the most interesting PHWE extracts were tested by agar diffusion tests. The extracts were tested on Pseudomonas fluorescens, Staphylococcus aureus, Yersinia enterocolitica, Yersinia pseudotuberculosis and Listeria monocytogenes. Except for blackcurrant juice press cake, PHWE extracts showed good antimicrobial effect on S. aureus, P. fluorescens, Y. enterocolitica and Y. pseudotuberculosis. No inhibition was detected on L. monocytogenes.
Biography:
Edwina Romanens completed her Master of Science ETH in Food Science in 2009. While working on her Master’s thesis at the Vrije Universiteit Brussel in the Research Group of Industrial Microbiology and Food Biotechnology, she studied the microbiology of Ecuadorian cocoa bean fermentation. After having worked for 4 years in the food industry as a technical sales assistant and project manager, she started her PhD at ETH Zurich with a focus on cocoa bean fermentation in Honduras.
Abstract:
Fermented dry cocoa beans are the basic raw material for the production of chocolate. Their fermentation is a spontaneous process and is characterized by a succession of yeasts, lactic acid bacteria (LAB), and acetic acid bacteria (AAB). Metabolites produced in the fermentation process are involved in the development of flavour precursors and the characteristic colour of fully fermented beans. As it is carried out on farms, cocoa bean fermentation is subject to various agricultural and operational practices, and hence the quality of the fermented dry cocoa beans obtained varies. The aim of our research was to develop a lab-scale model system adapted to a 5-day on-farm fermentation in Honduras, which can be used as a simple tool for optimizing the fermentation process. Five-day fermentations, each with up to 1 kg pulp-bean mass from hybrids of Trinitario, were performed in laboratory incubators followed by subsequent drying of beans in a small drying oven. During the fermentation process different parameters, such as temperature, pH, pulp content, and microbial counts of LAB, yeasts and AAB, were monitored. A final quality test of the dried beans was carried out using a traditional cut-test and sensory analysis. The lab-scale model-system developed during our study achieved similar physical parameters and microbial counts when compared to a Honduran on-farm cocoa bean fermentation. This enables the testing of various influencing factors, such as genetics, operational practices, or the application of starter cultures at small scale.
Yoshihisa Urita
Toho University, Japan
Title: The impact of Fucoidan on gut microbiota and gastrointestinal symptomms
Biography:
Yoshihisa Urita is working as a professor at Toho University. He is the department director of General Medicine and Emergency Care Center. He has completed his masters in medicine from Toho University School of Medicine in 1985. He has published more than 25 papers in reputed journals. He is the board member of Japanese Society of Endoscopy and Japanese Society of Hospital Medicine.
Abstract:
Introduction: Functional dyspepsia (FD) is a gastroduodenal disorder that presents as postprandial fullness, early satiation or epigastric burning despite no evidence of a structural disease that is likely to explain the symptoms for over 6 months. To FD patients we use various therapies, such as administration of proton pump inhibitors (PPIs), Acotiamide, histamine-type 2 receptor antagonists, prokinetic agents. However, the efficacy of these agents is limited. Fucoidan is a complex sulfated polysaccharide derived from marine brown seaweed (Mozuku). The effect of fucoidan has reported as anti-inflammatory, anti-coagulant, anti-thrombotic, anti-adhesive H. Pylori, anti-ulcerogenic, improvement of gastric emptying function, anti-tumor and anti-oxidant activities and so on. Patients & Methods: Between March 2015 and July 2015, we enrolled 5 patients who were diagnosed with FD. All patients already use some agents (e.g., PPI, Acotiamide and TJ-43). We have a questionnaire (FSSG) before, 4 weeks and 8 weeks after ingesting fucoidan soft capsule (240 mg/day for 4 weeks). This questionnaire (FSSG) is a self-report instrument containing 12 questions written in a simple and easy-to-understand language. As reported previously by Kusano and colleagues (2004), the following definitions were used to identify symptoms in the F-scale: “Do you get heartburn?â€; “Does your stomach feel bloated?â€; “Does your stomach ever feel heavy after meals?â€; “Do you sometimes subconsciously rub your chest with your hand?â€; “Do you ever feel sick after meals?â€; “Do you get heartburn after meals?â€; “Do you have an unusual sensation in your throat?â€; “Do you feel full while eating meals?â€; “Do some things get stuck when you swallow?â€; “Do you get bitter liquid coming up into your throat?â€; “Do you burp a lot?â€; and “Do you get heartburn if you bend over?â€. Symptoms frequency was measured on the following scale: Never=0; occasionally=1; sometimes=2; often=3 and always=4. If the patient has a score of more than 7 point, GERD is considered as positive. This study was carried out in accordance with the Declaration of Helsinki and approved by the ethical committee at Toho University. Results: It was recognized that FSSG score was decreased by ingesting fucoidan in 4/5 patients. Conclusion: It is concluded that ingesting of fucoidan will improve abdominal symptoms and FSSG score for refractory FD patients.
Carlos Eduardo Serrano Maldonado
National Autonomous University of Mexico, Mexico
Title: Bacteriocin production by Enterococcus spp. strains isolated from cotija cheese
Biography:
Carlos Eduardo Serrano Maldonado is currently a PhD student of Biochemical Sciences at National Autonomous University of Mexico. He has worked in the search and characterization of antibacterial compounds produced by lactic acid bacteria, including bacteriocins and peptidoglycan hydrolases. He is a Teacher of Food Chemistry at the Faculty of Chemistry of the National Autonomous University of Mexico.
Abstract:
Cotija cheese is an artisanal mexican food produced from whole raw milk. No thermal step, neither starter cultures are used in the process. After a three month ripening stage, it presents an acceptable microbiological quality and no pathogenic bacteria have been detected in it. This could be caused by the production of antibacterial compounds by lactic acid bacteria (LAB), like peptidoglucan hydrolases and bacteriocins. The LAB genus most commonly isolated from Cotija cheese is Enterococcus and several strains have shown antibacterial activity against Listeria monocytogenes and Staphylococcus aureus. Enterocin A is a pediocin-like bacteriocin produced by some Enterococcus faecium and E. faecalis strains. It belongs to class IIa bacteriocins which display a high anti-listerial activity that could be interesting for application as a food bio-preservative. In this work seven Enterococcus strains were isolated from artisanal Cotija cheese, which were identified as E. faecalis (QA1 and QB3) and E. faecium (QC4, QD2, QE2, QG5 and A5-1). They are non-pathogenic and they showed antibacterial activity against Listeria monocytogenes by agar diffusion assay. A specific PCR reveals that six of the seven strains harbor the gene that codes for enterocin A (entA). Its expression was detected by identification of mRNA, Tris-Tricine gel electrophoresis and zymography. These strains have a biotechnological potential for their direct application in fermented foods or to produce antimicrobial peptides for food formulation.
Myrna Elena Olvera Garcia
National Autonomous University of Mexico, Mexico
Title: Which is the role of Enterococcus spp. in the ripening process of a handmade cheese
Biography:
Myrna Elena Olvera Garcia has studied Food Chemistry at Chemistry Faculty at National Autonomous University of Mexico and completed a Master’s degree in Biochemical Science at the same institution, about the pathogenic and probiotic potential of Enterococcus spp. isolated from a Mexican handmade cheese. She is currently a PhD Student in Biochemical Science with a bioinformatic specialization directed to the comparative genomic analysis. In 2014 she was teaching at Faculty of Chemistry. She has published four papers focused in antibacterial compounds produced by lactic acid bacteria and genome sequencing of bacteria isolated from Heterotermes sp. Termite Gut.
Abstract:
Enterococci isolated from food have useful biotechnological traits, such as bacteriocin production and a probiotic behavior, however their role during ripening, related to enzymatic activities such as proteolysis and lipolysis is not fully elucidated. Nowadays, bacterial genome sequencing and bioinformatic analyses are useful to improve the knowledge of all coding sequences in a genome in order to have an insight of the biochemistry during ripening. In contrast, enterococci are the most controversial genus among lactic acid bacteria because they have been associated with nosocomial infections. Therefore, the aim of this work was to give a comprehensive outlook of the metabolic potential of one E. faecalis and one E. faecium strains, related to cheese ripening, through their genome sequencing. The strains were isolated from an artisanal dairy product namely Cotija cheese. Besides, a genomic comparative analysis was carried out in order to differentiate food strains from nosocomial ones and to establish biomarkers associated to the former. Genes related to a proteolytic and lipolytic activities were detected, as well as genes coding for enzymes involved in flavor and odor development. Furthermore, coding genes for antibacterial compounds (enterocins and peptidoglycan hydrolases) were identified. Through a comparative genomic strategy, genetic characteristic (absence of plasmids and low presence of the main virulence factors and of antibiotic resistence) were recognized to differentiate food from nosocomial strains. Additionally class II bacteriocin and type I restriction enzymes coding genes are proposed as biomarkers of adaptation to food environment.
Silvia Simona Grosu Tudor
Institute of Biology Bucharest of the Romanian Academy, Romania
Title: Physicochemical and rheological properties of some exopolysaccharides produced by lactic acid bacteria isolated from plant origin materials
Biography:
Silvia Simona Grosu Tudor has completed her PhD in 2009 at the Institute of Biology of the Romanian Academy. Her Postdoctoral studies were funded by The National Authority for Scientific Research, Ministry of Education, Research and Innovation, Romania. Her scientific experience is illustrated by the contribution to thirteen research projects, both national and international, as Collaborator to ten of them and as Director to other three. She has more than 20 original papers (of which 14 in international journals), 26 posters and 6 oral communications presented in national/international conferences.
Abstract:
Exopolysaccharides (EPS) produced by lactic acid bacteria (LAB) have gained considerable attention in the fermented dairy industry because of their potential application as viscosifiers, texturizers and emulsifying agents. EPS produced by the food-grade microorganisms with GRAS (generally recognized as safe) status are important sources of natural alternatives to commercial additives of plant or animal origin. In this study, LAB isolated from different plant origin materials was screened for their ability to produce EPS. The taxonomic affiliation of the EPS producing strains was determined on the basis of their 16S rRNA sequences. Nine of the 146 tested strains have been shown to produce EPS in MRS medium with sucrose, all belonging to Leuconostoc mesenteroides species. One strain, namely L. mesenteroides 109, has been shown to produce large amounts of EPS, of about 19 g/L. All isolated EPS have a high molecular mass of above 1400 kDa and a monomer composition dominated by the presence of glucose. The rheological properties and the EPS production in different growth media were studied for four LAB strains producing high amounts of EPS, L. mesenteroides 109, 112, 124, 127 and one strain, namely Weissella cibaria 120 that was not able to produce EPS when grown in MRS with sucrose. Among the EPS producing strains, the most promising one regarding the potential application in the food industry is L. mesenteroides 109, as it produces considerable amounts of EPS (over 25 g/l), together with a high viscosity (over 2400 mPa s) in soy milk supplemented with sucrose.
Medana Zamfir
Institute of Biology Bucharest of the Romanian Academy, Romania
Title: Characterization of a nisin-like bacteriocin produced by Lactococcus lactis 19.3, isolated from raw milk
Biography:
Medana Zamfir has completed her PhD in 2003 and is a senior scientist at the Institute of Biology of the Romanian Academy. Her main research topics are: lactic acid bacteria, food microbiology, biochemistry. The scientific experience is illustrated by the contribution to many research projects, both national and international. The main research results were included in more then 50 original papers, and many communications presented in national/international conferences.
Abstract:
Lactococcus lactis 19.3 was isolated from raw milk and identified by 16S rRNA gene sequencing. It produces a bacteriocin with a wide inhibitory spectrum, including other lactic acid bacteria (LAB) and strains of Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, and Staphylococcus aureus. The bacteriocin has a low molecular mass, it is heat resistant and stable in a wide pH range. In this study, the relation between bacterial growth and bacteriocin production was investigated in various media. Moreover, the mode of action was studied and the corresponding gene was sequenced. The producing strain was able to grow in cows milk and soy milk and the maximum bacteriocin activity was detected in the early exponential phase, as in MRS medium. The bacteriocin has a bactericidal, concentration- and strain-dependent effect. When added to concentrated suspensions of the sensitive cells, the bacteriocin caused a rapid decrease of the cells viability, and caused major morphological changes, as were observed by scanning electron microscopy. Moreover, the bacteriocin was able to completely repress the growth of the sensitive strains when added in a sufficient amount prior or immediately after inoculation. Finally, the bacteriocin was identified by sequencing the encoding gene. The presence of nisin gene was confirmed. The nucleotide sequence and the deduced aminoacids sequences were identical to those of nisin A. Based on all our data gathered so far, L. lactis 19.3 is a good candidate for a starter or protective culture in the manufacturing of both fermented dairy or vegetarian food products.
Njah Alonazi
Dublin Institute of Technology, Ireland
Title: Genetically modified foods as affected by microorganisms more than natural food in Food factories in Saudi Arabia
Biography:
Njah Alonazi is currently a PhD student at Dublin Institute of Technology, Ireland.
Abstract:
Genetically modified foods have been developed through the application of genetic engineering techniques. Genetically modified crops provide a significant advantage and hence enhance a higher yield and nutritional value. However, in Saudi Arabia, citizens have expressed concerns in understanding what they feed on. Mawgood, Gassem & Al-Doss (2010) carried out an investigation on genetically modified foods in Saudi Arabia, where they conducted a survey and tested two significant samples of the overall study. According to the study, the global trading and cultivation of genetically modified crops has enhanced a significant complexity in the management of microorganisms. The study illustrates that approximately 200 samples were also tested and among the samples approximately 20 products illustrated positive results which were one potato sample, corn samples and ground meat sample. According to the results, the ground meat illustrated a positive result as a result of being added soybean. According to their overall discussion, genetically modified foods were highly impacted by microorganisms as compared to the natural foods. They argued that the labeling requirement of genetically modified foods in Saudi Arabia was initiated to be approximately one percent maximum limit that illustrated the genetically modified foods. If a certain food commodity is initiated with genetically modified product then it is supposed to be illustrated with a triangle in order for the customers to understand what they take in those food commodities. On the other hand, Mawgood, Gassem & Al-Doss (2010) argued that the Saudi Arabia strived to ban the imports of genetically modified foods; therefore, crops that use genetic modified techniques are not allowed in the country.
Amal Alenezi
Dublin Institute Of Technology, Ireland
Title: Effect of food spoilage bacteria on food
Biography:
Amal Alenezi is a Ph. D. student at Dublin Institute of Technology, Ireland.
Abstract:
Food spoilage can be described as the process by which food quality becomes compromised and its edibility significantly reduced. Numerous signs are indicative of food spoilage and they range from changes in the ordinary appearance of the foods, changes in its texture, bad odor and poor taste. Although some spoiled foods may be consumed without causing harm, most of them are toxic in essence and may result in serious health complications. Microorganisms such as bacteria, insect larvae and fungi are responsible for food spoilage. Even with the present day preservation methods, food spoilage remains to be a significant problem in the contemporary food industries. Bacteria have the unique ability to form structures that are extremely resistant to harsh environmental conditions. These spores are resistant to freezing, high temperatures and other forms of drying. This makes them escape conditions in the conventional preservation techniques leading to the rotting of food. Some of the most common spore forming bacteria that resistant to various preservation methods belongs to the genus Bacillus and Clostridium. According to Doyle (2009), other species such as Erwinia carotovora are responsible for soft-rot type common in tomatoes. Additionally, blue mold rot in tomatoes is known to be caused by Fusarium as well as Penicillium species of bacteria. Pseudomona spp. which typically grows at a temperature of 4 ºC is also responsible for a significant portion of food spoilage. Two species of Pseudomonas, P. fragi and P. putrefaciens are chiefly responsible for the kind of spoilage that occurs in fermented milk products such as butter and cheese. Campylobacter butyricum and Campylobacter sporogenes have also been reported to cause this sort of decomposition. Botrytis cinerea and Guignardia bidwellii take credit for the kind of spoilage occurring in grapes and strawberry. Guignardia bidwellii cause big mummy rot in grapes. Therefore, it is evident that bacteria are a threat to food security.
Chimya Gundiri
University of Nottingham, UK
Title: Listeria monocytogenes contamination in bell peppers
Biography:
Chimya Markus Gundiri is currently a PhD student in the Food Sciences Department at The University of Nottingham. She has a Bachelor’s degree in Biomedical Sciences from The University of Manchester and a Master’s degree in Biotechnology from The University of Essex.
Abstract:
The internalization and activity of Listeria monocytogenes in growing plants to better understand the saprophytic lifestyle of the bacteria has remained a relatively unexplored area. Salad vegetables are a recognized vehicle for transmission of L. monocytogenes but the question of how it contaminates the produce in the first place has been neglected. Red bell peppers imported to a processing and packaging company which tested negative for Listeria monocytogenes upon arrival but positive after being cut open. The seeds of the peppers were identified as the source of contamination and the chemotactic response to the pepper isolates to several plant sugars was investigated. It was hypothesized that a small number of infected fruits were resulting in widespread cross-contamination of product after these fruit were cut open. A survey of bell peppers purchased from local shops was also carried out to investigate the frequency of isolation of Listeria monocytogenes. From the survey (n=40), 5 peppers imported from The Netherland tested positive for L. monocytogenes (5/40) while those imported from Spain and Morocco (n=20 of each) were negative. We will present data and images to show the response of Listeria monocytogenes to sugars and pepper extracts which suggests that the bacteria are repelled by the flesh of the peppers possibly due to its capsaicinoid contents but are attracted to the seeds inside the peppers. This suggests that an internal plant system could be the route of migration for the bacteria.
Madiha El Awamie
Nottingham University School of Biosciences, UK
Title: Identification of the antimicrobial effect of liquorice extracts on gram-positive bacteria: Determination of minimum inhibitory concentration and mechanism of action using a luxABCDE reporter strain
Biography:
Madiha El Awamie got MSc degree in 2007 at Benghazi University, Faculty of Science, Botany Department Benghazi Libya and she worked as lecturer assistant in Botany department at Benghazi University. Dissemination of research master's "Study of the quarterly change in the volatile oils marjoram plant in Libya," a scientific conference in Malaysia Year 8/2007. Now she is a PhD student at Nottingham University.
Abstract:
The public is demanding foods that are more natural and less processed; this has led to a search for new antimicrobial substances from other sources including plants. Liquorice plant is used as a traditional medicine in different countries around the world to treat many diseases including bacterial infections and also commonly used as flavouring in food products. The aim of this study is to evaluate the anti-bacterial activity of a Glycyrrhiza glabra extract as a natural preservative. This particular extract is derived from the waste material left over after processing of the plant material for food production. Antibacterial activity of liquorice extract was screened against eight species of Gram- negative and Gram-positive bacteria, including Listeria monocytogenes, Listeria innocua, Staphylococcus aureus, Enterococcus faecalis and Bacillus subtilis. The Gram negative bacteria include Pseudomonas aeruginosa, Escherichia coli and Salmonella typhimurium but none of these were affected by the extract. For all of the Gram-positive bacteria tested, growth was inhibited as monitored using optical density, but the cells were not killed since the cells were still viable when plated out. The Minimum inhibitory concentration [MIC] and Minimum bactericidal concentration [MBC] of the extract was also determined and a concentration of 50 µg ml-1 was found to have a strong bacteriostatic effect on Gram-positive bacteria. Microscopic analysis indicated that there were changes in cell shape and results using a bioluminescent reporter strain indicated that cell energy levels were reduced. Together these results suggest that the extract is inhibiting the growth of Gram-positive bacteria only by damaging the cell wall and/or membrane.
Biography:
Narjes Haji Dashti is currently working as an Associate Professor of Microbiology at the Department of Biological Sciences, Faculty of Science, Kuwait University. She has obtained her Master’s degree in the same field at Oregon State University, USA followed by a PhD at McGill University, Canada. Her research interests include plant pathology, virology, soil microbiology, microbial bioremediation and hydrocarbon degradation. Her primary research focuses include; the beneficial applications of plant growth promoting rhizobacteria (PGPR) on both leguminous and non-leguminous crops and the hydrocarbon degrading potential of hydrocarbonoclastic bacteria as a mean of bioremediation of oil spill contaminated sites. She has over 21 publications and has presented many of her finding in both national and international conferences. She is an active Member of international association of the agricultural economists, USA and the Genetics Society, UK.
Abstract:
A study of the effect of two plant growth promoting rhizobacteria (PGPR) strains, Pseudomonas aeruginosa and Stenotrophomonas rhizophila, on fruit yields and chemical contents on cucumber mosaic virus (CMV) infected tomato (Solanum lycopersicum) fruits was performed. Two CMV strains CMV-KU1 which is a locally isolated CMV associated with a benign viral satellite RNA and CMV-16 a satellite free virus that causes severe stunting, manifested by vegetative and fruit yield loss in tomato were used. The study was conducted in parallel on two different cultivar varieties of tomato, namely Supermarmande and UC82B and results obtained for each were compared. The results indicated that the presence of the PGPR almost doubled the average yield per plant, even of those plants infected by the CMV viruses, compared to the healthy control treatments. The chemical analysis of tomato fruits revealed that the presence of the PGPRs increased the total protein, lycopene, alkalinity and phenol content of the tomato fruits compared to the healthy controls. However, PGPRs had no influence on reduced sugars, total soluble solids or the titerable acid content but reduced the amount of ascorbic acid in tomato fruits of infected plants compared to healthy controls.