Melanin production from marine <i>Streptomyces</i>

Abstract

Melanin pigments are frequently used in medicine, food and cosmetic preparations. In this study, three strains among 21 Actinomycetes sp isolates produced a diffusible dark pigment on starch casein an agar medium which was water soluble. The pigment production was estimated using L-tyrosine as substrate. Among the strains, 3 (F1, F2, F3) were used for further analysis. Optimized culture condition for melanin production were; 1% of starch- best carbon source, 0.2% of soyabean- best nitrogen source, salinity- 15 ppt, temperature- 35°C, pH-7.0 and incubation time- 168 h. Sugarcane waste was found to be the cheaper and best source for melanin production. Melanin also showed activity against potential pathogens. The maximum antimicrobial activity was observed with Escherichia coli (20 mm) and Lactobacilus vulgaris (20 mm). F1 strain producing melanin was taken for FT-IR analysis. The FT-IR result confirmed that it was melanin pigment. Therefore, this study proved that sugarcane waste can be used for the production of melanin and it (melanin) has potential anti-bacterial activity.

Key words: Melanin, sugarcane waste, antibacterial, FT-IR.