Abstract:
The present study illustrates the antimicrobial potency against eight bacterial and four
fungal strains and the determination of MIC of crude extracts as well as purified
compounds of Mimosa pudica L (Fabaceae). The antioxidant activity was observed
through 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. The
phytoconstituents of crude extracts of leaf, stem and root were isolated through column
chromatography, thin layer chromatography (TLC) and GC-MS (Gas Chromatography-
Mass Spectrometry) analyses. Insecticidal and repellent activity was tested on
Cryptolestes pusillus.
Three gram-positive bacterial strains viz. Bacillus cereus, Staphylococcus aureus,
Bacillus zhanjiangensis and five gram-negative bacterial strains viz. Klebsiella
pneumoniae, Shigella boydii, Shigella sonnei, Escherichia coli and Salmonella typhi
were used for testing the antibacterial potency of petroleum ether, chloroform, ethyl
acetate and methanol crude extracts of leaf, stem and root as well as isolated pure
compounds of M. pudica and compared with standard antibiotic Ciprofloxacin
(5μg/disc). The chloroform extract of root showed the highest potentiality among all
the extracts of leaf, stem and root against all the bacterial strains where the zone of
inhibition was 21.67±1.45mm against S. sonnei at 200μg/disc concentration. The
susceptibility order of the extracts was: root > leaf > stem.
The antifungal activity was tested against four fungal strains viz. Rhizopus oryzae,
Fusarium proliferatum, Aspergillus niger and Candida albicans with a standard
Nystatin (50μg/disc). R. oryzae showed the highest (13mm in diam.) zone of inhibition
against ethyl acetate extract at 200μg/disc concentration, and that of for F. proliferatum
12mm against ethyl acetate extract, for A. niger12mm against chloroform extract and
for C. albicans 13mm against chloroform extract of root at the same concentration.-----
Description:
This Thesis is Submitted to the Institute of Biological Sciences (IBSc) , University of Rajshahi, Rajshahi, Bangladesh for The Degree of Doctor of Philosophy (PhD)
