Bay Leaves have Antimicrobial and Antioxidant Activities
Background: Bay, Laurus nobilis L is a native plant and is one of the most frequently used cooking spices. The dry Bay leaves are used to treat several digestive problems with anticonvulsive, narcotic and antibacterial properties. Thus, this study was aimed to investigate the in-vitro antimicrobial and antioxidant activities of different extracts of Bay leaves.
Methods: The dried Bay leaves were extracted sequentially with n-hexane, dichloromethane and methanol by Soxhlet apparatus. The extracts were concentrated and evaluated for antimicrobial activity against Staphylococcus aureus, Pseudomonas aeroginosa, E. coli and Candida albicans using well diffusion method to determine the diameter of zone of inhibition. Also, Bay leaves extracts were evaluated for antioxidant activity using qualitative DPPH assay.
Results: The findings of antimicrobial assay showed that methanolic extract of Bay leaves has an antibacterial activity against Staphylococcus aureus with zone of inhibition of 18 ± 0.8 mm, which is higher than phenol inhibition zone (10 ± 1.0 mm) whereas, no antibacterial inhibition against other tested bacteria was detected. The dichloromethane extracts inhibited E. coli growth with zone of inhibition of 14 ± 0.6 mm and with Staphylococcus aureus of 18 ± 0.8 mm, while, the n-hexane extract has no antibacterial activity with all of the tested organisms. However, all of Bay leaves extracts displayed no antifungal effect on Candida albicans. In terms of antioxidant activity, all of Bay leaves extracts exhibited antioxidant activity, but the methanolic extract displayed the most prominent level.
Conclusion: The bay leaves extracts have antibacterial and antioxidant activity and further investigations to assess these effects are recommended. arabic 6 English 50 Algabri So, Awatf Mohammed Ahmed Abadi, Basma Mohamed K Doro, Mahmud Shibah , Salem Al monder (8-2018)