STUDY OF ANTIMICROBIAL PROPERTIES OF CATHARANTHUS ROSEUS BY AGAR WELL DIFFUSION METHOD

Abstract

Antimicrobial activity of ethanolic, methanolic, aqueous and chloroform extracts of leaves, stems and flowers of Catharanthus roseus were studied against Escherichia coli , Pseudomonas aeruginosa ,Staphylococcus aureus, Candida albicans , Aspergillus niger and Aspergillus fumigatus by agar well diffusion method. Ethanolic leaf extract of Catharanthus roseus had shown antimicrobial activity against Candida albican, Pseudomonas aeruginosa, and Aspergillus niger (with zone of inhibition 14, 13 & 8 mm respectively). Ethanolic stem and flower extract had shown antimicrobial activity against Staphylococcus aureus and Aspergillus niger (with zone of inhibition 19, 6 mm by stem extract and 8, 10 mm by flower extract). Maximum antifungal activity against Candida albicans was exhibited by methanolic flower extract of Catharanthus roseus (18 mm zone of inhibition) followed by methanolic leaf extract (13 mm zone of inhibition) and then methanolic stem extract (11mm zone of inhibition). Chloroform flower extract of Catharanthus roseus had shown antibacterial activity against gram negative bacteria Pseudomonas aeruginosa (with zone of inhibition 4 mm). Aqueous leaves stem and flower extract of Catharanthus roseus were not effective against any bacterial and fungal strains. Hence the ethanolic extract is more useful for preparing the antibacterial drugs while metanolic extracts are useful for antifungal extract. Present study concludes that antimicrobial activity against selected strains varies among the different plant parts used and depends largely upon the extraction procedure, type of solvent used for extraction, and the bacterial strains tested