• Joseph Odewade Federal University, Dutsin-Ma, Katsina State, Nigeria.
  • Oluwasoga Department of Microbiology, Bayero University, Kano, Kano State, Nigeria.
  • Samuel Department of Microbiology, Federal University, Dutsin-Ma, Katsina State, Nigeria.
Keywords: Inhibitory effect, Acacia nilotica, Pathogenic bacteria, Pods, Antibacterial activity, Phytochemicals


This study assessed the inhibitory effects of the pod extract of Acacia nilotica against some pathogenic bacteria (Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococccus pyogenes). Fresh pods of Acacia nilotica were air-dried and then ground into fine powder. Thereafter, pod powder was extracted using ethanol and distilled water in the ratio 3 to 2 (v/v). The crude extract was concentrated in vacuo and lyophilized. Afterwards, screened for phytochemicals and tested for antibacterial activity against the bacterial isolates. Antibacterial potential, minimum inhibitory concentrations (MIC), and minimum bactericidal concentrations (MBC) of the extract were determined using standard microbiological method. Zone of inhibition shown by the crude extract at 50 mg/mL on the isolates ranged between 10 mm and 18 mm while MIC ranged between 1.56 mg/mL and 25 mg/mL. Minimum bactericidal concentrations ranged between 3.13 mg/mL and 50.00 mg/mL. The phytochemical screening of the extract revealed the presence of tannins, alkaloids, flavonoids, saponins and cardiac glycosides. This study, therefore, showed that pod extract of Acacia nilotica exhibited appreciable inhibitory effects on the test isolates. Hence, there is need for in vivo studies to complement the present findings.


Abdulhamid, A., Sani, I., Kankiya, I. H. and Fakai, I. M. (2019). Phytochemical

Screening, Analgesic Effect and Anti-inflammatory Activity of Crude Methanolic

Stem Bark Extract of Acacia nilotica (Linn.). Asian Journal of Biological Sciences.

(3): 450-456.

Akinpelu, D. A., Abioye, E. O., Aiyegoro, O. A, Akinpelu, F. O. and Okoh, A. I. (2015).

Evaluation of antibacterial and antifungal properties of Alchornea laxiflora (Benth.) Pax. &

Hoffman. Evidence-Based Complementary and Alternative Medicine, pp 6.

Aliyu, B. S. (2006). Common Ethno medicinal Plants of the Semiarid Regions of West Africa, Triumph Publishing Company Limited; Nigeria, pp.8–26.

Banso, A. (2009). Phytochemical and antibacterial investigation of bark extracts of Acacia nilotica. Journal of Medicinal Plants Research, 3(2): 082-085.

Ciocan, I. D. and Bara, I. I. (2007). Plant products as antimicrobial agents. Genetică È™i Biologie Moleculară; 8(1):151â€156.

Dharmananda, S. (2003). Gallnuts and the uses of tannins in Chinese medicine; Proceedings of

institute for Traditional Medicine; Portland, OR, USA.

Ganguly, T. and Sainis, K. B. (2001). Inhibition of cellular immune responses by Tylophora indica in experimental models. Phytomedicine, 8:348-355.

Gurib-Fakim, A., Brendler, T., Phillips, L. D. and Eloff, L. N. (2010). Green Gold—Success

Stories Using Southern African Plant Species, AAMPS Publishing, Mauritius.

Harborne, J. B. (2006). Phytochemicals technique. Bandung (ID): ITB Press.

Hugo, W. B. and Russell, A. D. (2015). Pharmaceutical Microbiology, 6th Edition Blackwell

Science, Ltd. OsneyMead Oxford OX2, 25 John Street, London.

Hussain, H., Badawy, A., Elshazly, A., Elsayed, A., Krohn, K., Riaz, M. and Schulz, B. (2011).

Chemical constituents an antimicrobial activity of Salix subserrata. Records Natural Products


Ikeda, Y., Fujii, Y., Nakaya, I. and Yamazaki, M. (1995). Quantitative HPLC analysis of cardiac glycosides in Digitalis purpurea leaves. Journal of Natural Products, 58:897-901.

Ikram-ul-Haq, J. and Muktar, H. (2016). Biosynthesis of protease from Lactobacillus paracasei: kinetic analysis of fermentation parameters. Indian Journal of Biochemistry and Bio- Physics, 43: 377-381.

Joshi, B., Lekhak, S. and Sharma, A. (2009). Antibacterial property of different medicinal plants: Ocimum sanctum, Cinnamomum zeylanicum, Xanthoxylum armatum and Origanum majorana, Journal of Applied Science and Engineering Technology, 5:143–150.

Kalaivani, T. and Mathew, L. (2010). Free radical scavenging activity from leaves of Acacia nilotica (L.) Wil . ex Delile, an Indian medicinal tree. Food and Chemical Toxicology, 48: 298-305.

Koube, J., Dongmo, S. S., Guiama, V. D. and Bum, E. N. (2016). Ethno medicinal survey of Gavdé (Acacia nilotica): a medicinal plant used in sahelian zone of Cameroon, Central Africa. International Journal of Innovation and Applied Studies, 16(4):820-827.

Maikai, V. A., Maikai, B. V. and Kobo, P. I. (2009). Antimicrobial properties of stem bark

extracts of Ximenia americana. Journal of Agricultural Science, 1(2): 30-34.

Okoro, S. O., Kawo, A. H. and Arzai, A. H. (2014). Phytochemical screening, antibacterial

and toxicological activities of Acacia nilotica extracts. Bayero Journal of Pure and Applied Sciences, 7(1):105-115.

Parekh, J. and Chanda, S. (2007). In vitro antibacterial activity of the crude methanol Extract of Woodfordia fructicosa Kurz. Flower (Lythaceae) Brazilian Journal of Microbiology, 38:204-207.

Pavithra, P. S., Janani, V. S., Charumathi, K. H., Indumathy, R., Potala, S. and Verma, R. S. (2010). Antibacterial activity of the plant used in Indian herbal medicine. International Journal of Green Pharmaceutical, 10:22-28.

Saini, M. L., Saini, R., Roy, S. and Kumar, A. (2008). Comparative pharmacognostical and

antimicrobial studies of Acacia species (Mimosaceae). Journal of Medicinal Plants Research,


Scalbert, A. (1991). Antimicrobial properties of tannins. Phytochemistry, 30(12):3875-3883.

Shanmughapriya, S. A., Manilal, A., Sujith. S., Selvin, J., Kiran, G. S. and

Natarajaseenivasan, K. (2008). Antimicrobial activity of seaweeds extracts

multi-resistant pathogens. Annals of Microbiology, 58:535-541.

Shimada, T. (2006). Salivary proteins as a defense against dietary tannins. Journal of Chemical

Ecology, 32(6):1149-1163.

Spence, A. L. R. and Spencer, J. F. T. (2004). Public Health Microbiology: Methods and

Protocols. Human Press Inc. New Jersey. pp. 325-327.

Suffredini, I. B., Paciencia, M. L. B., Varella, A. D. and Younes, R. N. (2006). Antibacterial activity of Brazilian Amazon plant extracts. Brazilian Journal of Infectious Diseases, 10(6): 400-402.

Tamil, S. A., Dinesh, M. G., Satyan, R. S., Chandrasekaran, B. and Rose, C. (2011). Leaf and seed extracts of Bixa Orellana L. exerts anti-microbial activity against bacterial pathogens. Journal of Applied Pharmaceutical Science, 1:116-120.

Trease, G. E., and Evans, W. C. (2002). Pharmacognosy. 15th ed. B Saunders, London. pp. 137- 440.

How to Cite