Production, Characterization and Optimization of Red Pigment Echinenone Produced by Micrococcus sp., Isolated from Soil

Abstract

In recent years, natural pigments are replacing synthetic colourants due to their undesirable side effects. Microorganisms are a major source of natural colours and can produce a variety of pigments that have high value in food and textile industries. In the present work, the isolation of a novel microbe capable of producing a stable and high intense red pigment and its optimization is attempted. In this study, purification, characterization and optimization of pigment production by a bacterium isolated from the anthill soil are reported. The bacterial isolate was biochemically identified as Micrococcus sp., and was confirmed with 16S rRNA gene sequencing. The effects of carbon and nitrogen source, temperature, pH and oxygen availability on pigment production were investigated. Optimum growth was observed with a pH 6 and 5% glycerol and incubation at 28°C at 220 RPM. Three pigments were extracted and purified by column chromatography. The extracted red pigment was characterized using UV-visible, Mass and NMR spectroscopy and was confirmed as the carotenoid, echinenone (beta, beta-Caroten-4-one). After optimization, a yield of 25.98 mg/L of total carotenoid was produced by Micrococcus sp. The extracted carotenoid pigment can be used as natural colouring agent in food and textile industry. Keywords: Microbial pigments, Carotenoids, Micrococcus, Natural dyes, Eco-friendly