Phytochemical and Antibacterial Potentials of Senna tora Leaf and Seed Extracts against Some Clinically Isolated Bacteria

Abstract

This study was carried out to determine chemical constituents and antimicrobial activities of extracts obtained from the leaves and seeds of Senna tora. The chemical compositions of the leaf and seed extracts were profiled using GC-MS while Gram positive (Staphylococcus aureus and Enterococcus faecalis) and Gram negative bacteria (Klebsiella pneumoniae, Salmonella typhi, Escherichia coli and Pseudomonas aeruginosa) were used to test for antibacterial potentials. GC-MS analysis showed that the main components in the leaf extract of S. tora were cisoleic acid (29.4%), 1, E-11, Z-13-octadecatriene (13.4%), palmitic acid (13.3%), 1,E-8,Z-10-pentadecatriene (11.4%) and stearic acid (11.0%) while methyl-1-allyl-2-hydroxycyclopentanecarboxylate (20.0%), 6,9- pentadecadien-1-ol (20.0%), cis-oleic acid (16.2%), methyl-7-hexadecenoate (7.5%) and palmitic acid (6.5%) were the most abundant components in the seed extract. The leaves showed a higher inhibitory effect than the seeds, with a zone of inhibition mean value that ranged from 12.3-18.5 mm, while that of seeds ranged from 10-16.5 mm. Klebsiella pneumoniae exhibited the highest susceptibility (18.5 mm), while Salmonella typhi showed the lowest (10 mm). The results of this study revealed that the leaves and the stems of the plant contained some medicinally active phytochemicals that may be important as antimicrobial agent.