Exploring the Antimicrobial Potential and Phytochemical Composition of Ocimum tenuiflorum Leaf Extracts: An Analytical Apporach

Aim: To explore the antimicrobial potential sand phytochemical composition of Ocimum tenuiflorum leaf extracts against Staphylococcus aureus, Escherichia coli, and Aspergillus niger.

Study Design: The dried Ocimum tenuiflorum leaves were extracted using decoction and digestion methods. Preliminary qualitative phytochemical analysis of the extracts was conducted. The antibacterial activity of the extracts was analyzed using the agar diffusion method, followed by determination of the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) against Staphylococcus aureus and Escherichia coli. The poisoned food technique was employed to assess the fungicidal activity of the extracts against Aspergillus niger. All experiments were conducted in triplicate, and the average values were depicted graphically.

Place and Duration of Study: Sahrdaya College of Engineering and Technology, Kodakara, and Centre for Research on Molecular and Applied Sciences, Thiruvananthapuram, from May to August 2023.

Methodology: Dried Ocimum tenuiflorum leaves were extracted by decoction and digestion methods. Preliminary qualitative analysis was performed to identify various phytochemicals. The extracts were evaluated for their MIC and MBC/MFC against Staphylococcus aureus, Escherichia coli, and Aspergillus niger.

Results: Preliminary phytochemical screening revealed that both types of extracts contained alkaloids and steroids. Flavonoids and terpenoids were exclusive to the decoction extract, while saponins were found only in the digestion extract. Both extracts exhibited increased zones of inhibition (ZOI) against Aspergillus niger, followed by Staphylococcus aureus and Escherichia coli. The MIC for the decoction extract was 250 µg/mL against both Escherichia coli and Staphylococcus aureus, while the MIC for the digestion extract was 500 µg/mL. The decoction extract demonstrated an inhibition rate of 52.692% at a concentration of 125 µg/mL against Aspergillus niger.

Conclusion: The findings of this study provide valuable insights into the pharmacological properties of Ocimum tenuiflorum, paving the way for further research on its potential therapeutic applications and role as a natural preservative. The presence of diverse phytochemicals, coupled with observed antimicrobial effects, suggests its potential for multifaceted therapeutic benefits.