Antimicrobial Studies

Student: Beatrice Chidimma Nnaji (Project, 2025)
Department of Microbiology
Chukwuemeka Odumegwu Ojukwu University, Uli, Anambra State


Abstract

The global rise of antimicrobial resistance (AMR) poses a significant threat to public health, leading to a pressing need for comprehensive antimicrobial studies. This project aims to investigate the efficacy of various antimicrobial agents against a spectrum of pathogenic microorganisms, including bacteria, fungi, and viruses, with an emphasis on multi-drug resistant (MDR) strains. Our research employs a multidisciplinary approach, integrating microbiology, molecular biology, and bioinformatics to elucidate the mechanisms of action and resistance. This study investigated the antimicrobial properties of ethyl acetate and methanol extracts from Azadirachta indica and Chromolaena odorata against three bacterial strains: Staphylococcus aureus, Bacillus cereus, and Escherichia coli. The antimicrobial activity was assessed using the agar well diffusion method, and the results were measured as zones of inhibition at varying concentrations. The methanol extract of Azadirachta indica exhibited significant antimicrobial activity against Bacillus cereus, particularly at 125 µg/mL, demonstrating its potential as an effective natural antimicrobial agent. In contrast, the ethyl acetate extract of Azadirachta indica showed limited activity against the tested bacterial strains, with minimal inhibition observed. For Chromolaena odorata, the ethyl acetate extract displayed moderate activity against Bacillus cereus but was less effective against Staphylococcus aureus and Escherichia coli. The methanol extract, however, showed considerable inhibition of Bacillus cereus, indicating its promising antimicrobial potential. Overall, this study highlights the potential of Azadirachta indica and Chromolaena odorata extracts as sources of natural antimicrobial agents. While the methanol extracts demonstrated more substantial activity, further research is needed to optimize the extraction process and explore the full antimicrobial capabilities of these plants for potential therapeutic applications.

Keywords
antimicrobial studies