IN VITRO EVALUATION OF ANTIBACTERIAL PROPERTY OF CATHARANTHUS ROSEUS (LINN.) G. DON. VAR. “ROSEA” AND “ALBA”

Abstract

Objective: To evaluate the antibacterial property of crude, aqueous and organic solvent extract from leaf, stem and root parts of two different var. of Catharanthus roseus (i.e. “rosea” and “alba”) under in vitro conditions on various human pathogenic bacteria.Methods: Antibacterial activity of crude (fresh), aqueous, ethanolic, methanolic and equimolar (1:1) mixture of ethanolic dried leaf extract of variety “rosea” and “alba” was evaluated against various pathogenic bacteria viz. Bacillus subtilis, Escherichia coli and Staphylococcus aureus by disk diffusion method under in vitro conditions.Results: Gram-positive bacteria were found to be more susceptible than Gram-negative. Dried extracts of root, stem and leaf of C. roseus var. “rosea” and “alba” plants showed maximum antibacterial potency against all the test microorganisms. The equimolar mixture of ethanolic dried leaf extracts of species “rosea” and “alba” exhibited the maximum zone of inhibition against B. subtilis, E. coli and S. aureus as compare to extract prepared from individual parts. The findings of the ethanolic mixture of dried leaves of the two varieties on the tested bactera confirm that the effect is potentiating which may be synergistic or additive.Conclusion: From the findings, it could be inferred that C. roseus var. “rosea” and “alba” could be efficiently used in the development of new life-saving drugs against bacterial pathogens.