ANTIMICROBIAL ACTIVITY OF CRUDE EXTRACTS OF SENNA SINGUEANA (DELILE) LOCK (FABACEAE)

Abstract

Senna singueana, locally called ‘’rumfu’’ in Hausa, is used traditionally for venereal diseases, cough, wounds, eye
infections, etc. This study aims to justify the traditional uses of Senna singueana leaves in microbial infections.
Plant materials were collected, authenticated, powdered and extracted successively using n- hexane, ethyl acetate
and methanol. Preliminary phytochemical screenings were carried out using standard methods. The antimicrobial
activity was assessed using the agar well diffusion method. Microorganisms used were; gram-positive bacteria
(Staphylococcus aureus, Streptococcus faecalis,), gram-negative bacteria (Escherichia. coli, Pseudomonas
aeruginosa, Shigella dysenteriae Campylobacter jejuni, Salmonella typhi, Neiseria gonorrhea, Proteus mirabilis)
and fungi (Candida albican, Candida tropicalis and Candida Krusei). Ciprofloxacin and Fluconazole were used as
standards. Hexane, ethyl acetate and, Methanol extracts were obtained. The presence of flavonoids, alkaloids,
triterpenes, and glycosides were detected. The ethyl acetate extract (EE) was found to be the most effective, showing
the highest zone of inhibition against E. coli, Strep. faecalis, and Staph. aureus. N. gonoreae, P. aeruginosa, C.
jejuni and P. mirabilis were resistant to all extracts. The Minimum Inhibitory Concentrations (MIC) values of EE
were from 1.25 mg/ml to 5 mg/ml and Minimum Bactericidal/fungicidal Concentrations (MBC/MFC) values were
from 2.5 mg/ml to 10 mg/ml. The Results from this study validate the traditional use of S. singueana leaves in
microbial infections. Further study on EE extract to identify the bioactive constituents responsible for this activity is
recommended.