Isolation, Identification and Antioxidant Activity of Melanin Pigment from Actinomycete (Streptomyces Species) Isolated from Garden Soil, Nagpur District, India

Three strains among 20 Streptomyces isolates produce a diffusible dark brown pigment on both peptone-yeast extract agar and Streptomyces isolation agar. They also showed the positive reaction towards L-tyrosine substrates. The pigment has been referred to be dark brown water soluble pigment, as melanin. The present study reports antioxidant activity of melanin pigment from Actinomycete (Streptomyces species) strain isolated from garden soil, Nagpur district, India. Melanin production by the strain was further confirmed using tyrosine agar. Melanin production was carried out by adopting solid state fermentation using wheat bran and rice bran medium and extracted using ethyl acetate. About 220 mg/10 gram and 198 mg of crude pigment were extracted from 10 gram of wheat bran and rice bran medium, respectively. The melanin pigment from crude extract was partially purified by TLC and the purified melanin fraction showed promising free radical scavenging activity in DPPH method. Further fermentation and purification of melanin pigment from strain D5 will leads to a development of pharmaceutically valuable antioxidant.