Comparison of Antimicrobial Activity of Different Extract of Ocimum tenuiflorum L. leaf and Stem

Abstract

Aims: We aim to evaluate and compare the antimicrobial activity of extracts from the leaves and stems of Ocimum tenuiflorum L. Various extractions in different solvents were compared to determine the extract with the best performance against bacteria, fungi, and yeasts. Study Design: Prospective. Place and Duration of Study: Food Technology Division, School of Industrial Technology Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia. This study was developed as prospective. Methodology: Different extracts of non-polar and polar solvents were obtained from the macerate method from leaves and stems of O. tenuiflorum. The antimicrobial activities of these extracts were evaluated against selected Gram-positive and Gram-negative bacteria and fungal and yeast strains via the following method: inhibition zone, minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), and minimum bactericidal concentration (MBC). Results: The antimicrobial activity tests were performed using common pathogenic bacteria (Escherichia coli, Salmonella typhimurium, Klebsiella pneumoniae, Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, and Listeria monocytogenes), yeast (Candida tropicalis and Saccharomyces cerevisiae), and fungus (Aspergillus niger and Penicillum sp.). O. tenuiflorum L. stem or leaf extracts were more or less active against most of the tested pathogenic strains. The inhibition zone ranged from ≥9 mm to ≤15 mm. The most susceptible bacterium and fungus were L. monocytogenes (IZ=≥10–14 mm; MIC = 6.5mg/ml) and A. niger (IZ = ≥15 mm; MFC = 3.12 mm), respectively. Conclusion: The methanol and hexane extracts of O. tenuiflorum L. showed antimicrobial activities and exhibited significant potential as natural antimicrobial agents. By contrast, the water, ethyl acetate, and chloroform extracts from the leaves and stems of O. tenuiflorum L. can inhibit the microorganisms. All extracts from the leaves and stems failed to inhibit the E. coli, S. typhimurium, S. aureus, and C. tropicalis. However, further studies are still required.