Thermotolerant Bacillus subtilis Isolated from the soil samples collected under the brick furnace Warangal District, Telangana, India

Abstract

The present study focuses on the isolation and identification of soil bacteria from two distinct regions Devannapet and Hasanparthy District Hanumakonda, State Telangana, India, to characterize the dominant bacterial species based on morphological, physiological, and biochemical parameters. Soil samples collected from both locations were subjected to standard microbiological techniques for bacterial isolation and purification. Morphological characterization revealed colonies exhibiting powdery textures and Gram-positive, endospore-forming, rod-shaped cells typical of the genus Bacillus. Physiological analysis indicated that the isolates could grow optimally at temperatures ranging from 25°C to 45°C under facultatively anaerobic conditions, further supporting the identification of Bacillus-type bacteria. Biochemical tests demonstrated positive reactions for glucose fermentation, catalase, oxidase, and urease, and negative results for indole and citrate utilization. These cumulative findings confirmed the identity of the predominant isolate as Bacillus subtilis. The results align with previously published reports describing B. subtilis as a metabolically versatile, spore-forming bacterium capable of surviving in diverse environmental conditions. This study highlights the ecological significance of Bacillus subtilis in soil nutrient cycling and its potential application in agriculture and biotechnology.