Antifungal efficacy of pyocyanin produced from bioindicators of nosocomial hazards

Abstract

Pseudomonas, a common bacterium is found in soil, water, skin flora and in most of the man made environments such as Hospital, Industry, Effluent treatment plant. Pseudomonas aeruginosa one of the most important opportunistic pathogen which causes nosocomial infections to the patient in Intensive care unit has become a major threat in the medical care. It also exhibits multidrug resistance which has drawn the attention of the microbiologist. The characteristic feature of Pseudomonas aeruginosa is the production of soluble green pigment pyocyanin, which act as a bio-indicator for the identification of a contaminant in hospital environment. Pyocyanin produced as a secondary metabolite exhibits antifungal activity by both disc diffusion and liquid culture methods. The present study was undertaken to determine the frequency of occurrence of Pseudomonas aeruginosa in patient population attending an outpatient department. The study also includes to demonstrate the pigment production on various solid and liquid media. Further, the pigment pyocyanin was extracted and confirmed by using the solvent chloroform. The pigment was separated by thin layer chromatography and purified by column chromatography. Fraction which was obtained from TLC was used to determine the MIC and the antifungal activity against Candida albicans, Candida tropicalis, Candida glabarata Cryptococcus neoformans and Aspergillus fumigatus which concluded that pyocyanin pigment has the ability to inhibit the growth of various fungi by arresting the electron transport in both in vitro and in vivo conditions.