SUSCEPTIBILITY OF MICROBIAL INFECTIOUS AGENTS TO THE LATEX AND LEAF EXTRACT OF Calotropis procera

Abstract

The age-old traditional usage of the Calotropis procera plant for the treatment of several
infectious diseases has established the plant as ethnomedicinal with widely reported
exploitation in current herbal medicinal practice. This prompted the investigation of the in
vitro susceptibility of various disease-causing microorganisms to various doses of the latex
and leaf extract of the C. procera plant. The latex and leaves of the C. procera plant were
collected and processed before subjecting the leaf to ethanol extraction via the maceration
protocol. The various concentrations of the latex and leaf extract of C. procera were
subjected to antimicrobial susceptibility tests using the agar well diffusion technique. The
Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC)
were determined according to standard microbiological methods. The C. procera latex
exhibited antimicrobial activity against microbial isolates even at the lowest concentration of
20 % (v/v) except for E. coli which was not susceptible at this concentration. Lower
antimicrobial activity was observed with the leaf extract of C. procera even though antifungal
activity against C. albican was high with both the latex and the leaf extract. The MIC of the C.
procera latex detected at 12.5 and 25 % (v/v) and MBC at quarter strength of the latex also
emphasized the inhibitory and bactericidal capability of the C. procera latex against bacterial
infectious agents of clinical origin. The study attributed the antimicrobial potency of the C.
procera latex and leaf extract to its phytochemicals as widely referred in the literature. As per
findings from this study, C. procera could serve as a valuable pharmacological prospect for
the development of new natural antimicrobial drugs from plant sources that could be useful in
combating today's menace of antibiotic resistance.