Isolation, Characterization and Antimicrobial Evaluation of Melanin Produced by Streptomyces thermocarboxydus (RSMLAC01)
Author : Priyanka Kande Patil and Sagar Dapke
Abstract :
Actinomycetes are often said to produce all kinds of pigmentation species on various media. They are abundant in soil and hot regions like hot water springs. Water samples for microbial isolations were taken from hot spring Ganpatipule, Ratnagiri district of Maharashtra State. Isolation of microorganisms was carried out with a minimal salt medium. These isolates were cultured on iron rich yeast extract peptone agar to determine their potential for melanin pigment preparation. The isolated strain was then sent for 16-S RNA sequencing. Actinomycetes producing dark black pigments were kept in spores in a 10% glucose solution. These spores were inoculated into seed producing broth. Subsequently, this seed medium was inoculated in large production medium for 2-3 days at 30°C. UV-Vis spectroscopy was made after the melanin pigment produced to check if it is able to absorb the UV radiations. PDA plates and nutrient agar plates of different microbial cultures were prepared to assess the antimicrobial activity of the pigment. With the growing significance of melanin for pharmaceutical and cosmetic products, this study aimed to obtain pigment-producing Actinomycetes isolated in extreme environments. New strain RSMLAC01, isolated from the hot springs of Ganpatipule, Maharashtra, was isolated from the soil and confirmed as Streptomyces thermocarboxydus by 16S-rRNA sequencing. The strain showed well-defined extracellular melanin production through L-DOPA pathway. The purified melanin had typical UV-Vis absorption peaks at 221 nm and showed significant antimicrobial activity against several fungal and bacterial pathogens, indicating a promising bioactive action for cosmeceutical and biomedical applications.
Keywords :
Actinomycetes, Hot springs, 16S rRNA sequencing, UV-Vis spectroscopy, Antimicrobial activity.
