Food Microbiology

Statement of the Problem: Aromatic plants and their essential oils have been used since antiquity in flavor and fragrances, as condiments or spices, in medicines, as antimicrobial/insecticidal agents, and to protect stored products. Eucalyptus globulus plant is known for its richness on bioactive compounds such as essential oils, phenolic acids, flavonoids and hydrolysable tannins. Because of their multiple biological activities essential oils of E. globulus are used in medicine, perfume and food industry.

 

Methodology & Theoretical Orientation: The present study was undertaken: to determine the chemical composition of essential oils extract from Eucalyptus globulus (E. globulus) fruits, using gas-chromatography coupled with mass spectrometry (GC/MS) method and to examine their antibacterial effects against reference pathogenic strains: Staphylococcus aureus (S. aureus), Bacillus subtilis (B. subtilis), Listeria innocua (L. innocua), Escherichia coli (E. coli), Pseudomonas aerugenosa (P. aerugenosa), compared to that of two antibiotics tetracycline and gentamicin.

 

Findings: Twenty eight volatile compounds were identified, with the predominance of sesquiterpenes and oxygenated sesquiterpenes compounds (61.2%). The antibacterial activity shows an inhibition effect of essential oils extracts against all the tested bacteria with MIC of 3 and 4 mg mL-1. A bactericidal effect is observed, with MBC varying between 3.62 and 9.05 mg mL-1, which demonstrates the sensibility of all tested bacteria to the essential oils of E. globulus fruits.

 

Conclusion & Significance: The high yield and the results of antibacterial activity found for the studied essential oil extracts from E. globulus fruit made them good candidates for their use in pharmaceutical and food industries.