Exploration of Thermophilic Microorganisms from Hot Water Spring for Production of Industrial Enzymes

Abstract

Microorganisms are an inexhaustible pool for obtaining enzymes and several newlinebioactive molecules. The existence of microbes in extreme niche such as hot springs newlinemarks their candidature to explore diversity of their habitat. Thermophiles are an newlineexclusive class of microorganisms that thrive in temperature range (50°C-70°C). They newlineare of immense interest because their products have better stability and activity at newlinehigher temperature as compared to mesophiles and hence find applicability in major newlineindustrial processes. Surajkund is one such hot spring situated in Hazaribagh, newlineJharkhand. It is a neutral hot spring with pH 7.0 and a surface temperature of 85°C newlinethat rises up to 90°C by evening. Its microbial diversity was underexplored hence the newlinesite was chosen for exploration of thermophiles and thermozymes. In the present newlinework, 41 isolates were obtained from samples of Surajkund hot spring, at three newlinedifferent isolation temperatures (50°C, 60°C, and 70°C). Thermophilic isolates of newline60°C, and 70°C were of particular interest. Isolates of 70°C (BITSNS038, newlineBITSNS039, BITSNS040, and BITSNS041) were the producers of thermozymes, newlinenamely amylase, xylanase, and cellulase, respectively. Among four isolates, three newlineisolates demonstrated all three enzymatic activities, i.e. amylolytic, xylanolytic and newlinecellulolytic on agar plate assay conditions at 70°C. BITSNS038 was chosen for newlinephenotypic and 16S rRNA identification and was affiliated to Geobacillus icigianus. newlineThermophilic strain G. icigianus had amylolytic index of 1.58, xylanolytic index of newline1.5 and cellulolytic index of 2.3 on plate assay, and amylase activity of 0.81 U/mL, newlinexylanase activity of 0.72 U/mL and cellulase activity of 0.15 U/mL after 24 h of newlinegrowth in submerged conditions. Further studies on optimization, characterization, newlineand purification of thermostable amylase from G. icigianus (BITSNS038) were newlinecarried out. The optimum conditions obtained were (Starch 7.5 g/L, Tryptone 3.0 g/L newlinewith pH 7.0, 70°C, 150 rpm, and 18-24 h incubation). Crude amylase had