Evaluation of antibacterial effects of stem extracts from Coscinium fenestratum.

Abstract

An increasing number of pathogens are becoming antimicrobial resistant, among them are bacteria Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Enterobacter species, Pseudomonas aeruginosa, known as ESKAPE pathogens. These ESKAPE pathogens have been cited as one of the leading causes of nosocomial infections around the world and have shown higher antimicrobial resistance posing a great clinical challenge and the need of new therapeutic agents. Various plant extracts have been used in traditional medicine since ancient times. Coscinium fenestratum, commonly called yellow vine is a vine native to South Asia and has been used to treat common cold, tetanus, fever, inflammation, wounds, and diabetes especially in countries such as Sri Lanka and India. In this study we extracted the secondary metabolites from dried C. fenestratum stem. The extract was then tested for antimicrobial properties using disc diffusion method. The bacteria assayed include Pseudomonas putida, Mycobacterium smegmatis, and Acinetobacter baylyi which are the safer relatives of P. aeruginosa, M. tuberculosis, and A. baumannii respectively. Methanolic extract of C. fenestratum at 100 µg did not show any antimicrobial activity against M. smegmatis. The effects of the extract will be tested further against P. putida and A. baylyi. If the tests show antimicrobial properties, we will determine the chemical composition of the methanolic extract revealing the chemical agent which is active on the bacteria. Our work will provide valuable information on potential use of C. fenestratum secondary metabolites in treating human pathogens contributing to the drug discovery pipeline.