Determination of Antimicrobial Activity of Medicinal Plant Cassia obtusifolia L. (Chakunda) Leaf Extract on Selected Pathogenic Microbes

Pathogenic microorganisms are major health concerns of infectious diseases. In the present study ethanolic and methanolic extracts of Cassia obtusifolia leaves from Kushtia region (Bangladesh) were subjected to evaluate the in vitro microbial activity against six important human pathogenic bacteria viz., Bacillus subtilis (001-1), Sarcina lutea (002-1), Xanthomonas campestris (004-1), Escherichia coli (005-1), Klebsiella pneumonia (006-1) and Pseudomonas sp. (010-1) employing disc diffusion method. The crude methanolic extract of C. obtusifolia produced maximum area of inhibition (14 mm) against S. lutea (002-1) and crude ethanolic extract of C. obtusifolia produced the largest area of inhibition (11 mm) against K. pneumonia (006-1). The MIC values (256 μg/ml, 512 μg/ml) were obtained from the methanolic isolate and ethanolic extract that produced 4 mm and 3 mm area of inhibition against S. lutea (002-1) and K. pneumonia (006-1). The methanol extract showed greater activity than ethanol extract. The most susceptible bacterial strains to ethanol and methanol extracts were S. lutea (002-1) and K. pneumonia (006-1). So, it may be possible that the production of a new antibiotic from C. obtusifolia L. leaf may be recommended for meningitis and pneumonia. The findings of this research suggest that the extracts of C. obtusifolia L. can be a source of natural antibacterial agents with pivotal applications in pharmaceutical companies to control pathogenic bacteria causing severe illness in humans.