Isolation and Characterization of Bioactive Actinomycetes from Forest Soils of Kinnerasani Wildlife Sanctuary, Telangana

Abstract

Forest ecosystems represent rich reservoirs of microbial diversity with enormous biotechnological potential. Among soil microorganisms, actinomycetes are particularly important due to their ability to produce a wide range of bioactive metabolites including antibiotics, enzymes, antifungal compounds, and plant growth-promoting substances. The present study aimed to isolate and characterize bioactive actinomycetes from soils of the Kinnerasani Wildlife Sanctuary located in Bhadradri Kothagudem District, Telangana. Soil samples were collected from multiple ecological niches including rhizosphere zones, leaf-litter–rich soils, shaded forest floors, and moist regions near water bodies. Samples were processed using the serial dilution technique and plated on selective media such as Glycerol Yeast Extract Agar and Starch Casein Agar to facilitate actinomycetes isolation. Distinct colonies showing typical actinomycetes morphology were purified and preserved for further analysis. Morphological observation, Gram staining, and biochemical tests including catalase activity, oxidase reaction, and starch hydrolysis were performed for preliminary characterization. Most isolates exhibited Gram-positive filamentous structures and demonstrated strong catalase activity, confirming their actinomycetal nature. Starch hydrolysis results indicated significant extracellular enzyme activity among several isolates. Enumeration studies revealed a diverse microbial population dominated by Gram-positive rods, cocci, and filamentous organisms across different soil samples. The diversity observed in forest soils indicates the presence of metabolically versatile microorganisms capable of producing valuable bioactive compounds.