PRODUCTION AND PARTIAL CHARACTERIZATION OF PIGMENTS PRODUCED BY KOCURIA SP BRI 36: INFLUENCE OF HEAVY METALS

摘要

Objective: To study the production of pigments by Kocuria sp. BRI 36, their characteristics and influence of heavy metals on pigments. Methods: The effects of various physical and chemical parameters on pigments production by Kocuria sp. BRI 36 were examined. Pigments were extracted and partially characterised by Thin Layer Chromatography (TLC) and Fourier Transform Infrared Spectroscopy (FTIR). The effects of heavy metals such as Pb 2+ , Cd 2+ , Ni 2+ and Cr 3+ were studied on pigment production. Antimicrobial activity and stability studies of crude pigment were also conducted. Results: Kocuria sp . BRI 36 isolated from cold oceanic region maximally produced red-orange pigment in presence of glucose (5% w/v) and protease peptone (0.2% w/v) at pH 7.5, 10±1 °C. Thin layer chromatography (TLC) analysis revealed the occurrence of three different compounds in the crude pigment belonging to carotenoid and xanthophyll group. Metals like Ni 2+ and Cr 3+ adversely affected pigment production while Pb 2+ and Cd 2+ enhanced the yield. The significant features of Kocuria sp . BRI 36 pigment are i) antimicrobial activity against Gram-positive and Gram-negative bacteria, ii) maximum stability at pH 7.5 and 10±1 °C and iii) ~38% color loss at 50±1 °C in 5 h. Conclusion: Our results suggest application potential of Kocuria sp. BRI 36 pigments in various biotechnological fields.