Authors : Haruna Sabo Suleiman; Muhammad Abubakar Muhammad; Usman Ali Muazu; Halima Umar Abdullahi; Luka Obidah Ali

Volume/Issue : Volume 11 - 2026, Issue 7 - July

Google Scholar : https://tinyurl.com/36m53hpy

Scribd : https://tinyurl.com/322rht4a

DOI : https://doi.org/10.38124/ijisrt/26jul508

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Abstract : The rise of antibiotic-resistant bacteria has increased the need for effective plant based antimicrobial agents. Neem (Azadirachta indica), a widely used medicinal plant, contains numerous bioactive compounds with reported antibacterial properties. This study investigates the antibacterial effects of neem leaf and bark aqueous extracts against Escherichia coli, a common pathogen found on human skin. Skin swabs were collected from students of Federal University Gashua, and E. coli was isolated and cultured using standard microbiological procedures. Neem leaf and bark were collected, shade-dried, ground into powder, and extracted using aqueous solvent. Antibacterial activity was evaluated using the agar well diffusion method, while the minimum inhibitory concentration (MIC) was determined through serial dilution. Results showed that both neem leaf and bark extracts exhibited inhibitory effects against E. coli, with the leaf extract producing a larger zone of inhibition (3.5 cm at 10⁻¹ concentration) than the bark extract (3.1 cm at 10⁻¹). Activity decreased with further dilution, and no inhibition was observed from 10⁻⁴ onward. The findings demonstrate that neem leaf and bark possess antibacterial properties and could serve as potential natural alternatives to synthetic antibiotics. The study highlights the relevance of neem in developing affordable, plant- based treatments for bacterial infections, particularly in rural communities where access to antibiotics is limited.

Keywords : Neem, Escherichia Coli, Bacteria, Leaf and Bark.

References :

1. Alzohairy, M. A. (2016). Therapeutic Role of Azadirachta indica (Neem) and Their  Active Constituents in Disease Prevention and Treatment.Evidence-Based  Complementary and Alternative Medicine, 2016, 1-11.
2. Alzohairy, M. A. (2016). Therapeutic role of neem. International Journal of Pharmacognosy and Phytochemical Research, 8(2), 1–10.  Antibacterial effects of Azadirachta indica leaf and bark extracts in clinical isolates of  diabetic patients. NJIRM, 2(1), 34–40.
3. Banerjee, S., & Panda, S. (2017). Neem and its antibacterial activity. Journal of Pharmacognosy, 5(1), 12–19.
4. Banerjee, S., Mullick, H., & Banerjee, J. (2012). Zingiber officinale: A natural gold. International Journal of Pharmaceutical and Biomedical Sciences, 3 (1), 17-24.
5. Biswas, K., Chattopadhyay, I., Banerjee, R. K., & Bandyopadhyay, U. (2022). Biological  activities and medicinal properties of neem (Azadirachta indica). Current Science,  82(11), 1336-1345.
6. Biswas, K., Chattopadhyay, I., Banerjee, R. K., & Bandyopadhyay, U. (2002).  Biological activities and medicinal properties of neem. Current Science, 82(11),  1336–1345.
7. Campos, E. V. R., Proença, P. L. F., Oliveira, J. L., Bakshi, M., Abhilash, P. C., &  Fraceto, L. F. (2016). Neem oil and crop protection: From now to the future.  Frontiers in Plant Science, 7, 1494.
8. Chatterjee, S. (2020). Neem (Azadirachta indica) and Its Potential in Antimicrobial. Therapy. Journal of Medicinal Plants Research, 14(5), 231-240.
9. Cheesbrough, M. (2002). District Laboratory Practice in Tropical Countries. Cambridge University Press.
10. Girish, K. (2018). Neem–A Green Treasure. Electronic Journal of Biology, 4 (3), 102- 111.
11. Herrera-Calderon, O., Ayala-Rodriguez, V., Arroyo-Acevedo, J. L., Rojas-Armas, J. P., & Chumpitaz-Cerrate, V. (2019). Antibacterial activity and chemical composition of neem (Azadirachta indica) leaf extracts. Asian Pacific Journal of Tropical Biomedicine, 9(6), 259-265.
12. Herrera-Calderón, O., Ayala-Rodríguez, V., Arroyo-Acevedo, J., & Rojas-Armas, J. (2019). Antibacterial activity of neem leaf extracts. Asian Pacific Journal of  Tropical Biomedicine, 9(6), 259–265
13. Mogal, R. T., Londhe, V. P., Shastri, J. P., & Banerjee, S. K. (2018). Neem and its uses in  medicine and pharmaceuticals: A review. Journal of Pharmacognosy and Phytochemistry, 7(5), 129-137.
14. Mogal, S. et al. (2018). Herbal medicine usage globally: A review. Journal of Herbal  Medicine Research, 4(1), 10–18.
15. Montgomery, D. C. (2021). Design and Analysis of Experiments. John Wiley & Sons.
16. Nagini, S. (2015). Neem limonoids: Modulation of microbial pathways. Environmental  Toxicology and Pharmacology, 39(3), 829–837. Girish, K., & Shankara, B. (2008). Neem—a tree for solving global problems. Current Science, 94(7), 911– 916.
17. Pauler, S., Weisser, S., & Herrmann, M. (2019). Antibiotic resistance and medicinal  plants: A natural approach to combating bacterial infections. Natural Product Communications, 14(7), 1-10.
18. World Health Organization. (2020). Traditional medicine and medicinal plants in disease treatment. WHO Press.