TY - JOUR AU - Timilsina, Parash Mani AU - Pandey, Gyanu Raj AU - Shrestha, Asmita AU - Ojha, Manish AU - Baral, Garima AU - Karki, Tika Bahadur PY - 2020/12/19 Y2 - 2024/03/29 TI - Purification and Characterization of a Noble Thermostable Alpha-amylase from Anoxybacillus tengchongensis RA1-2-1 Isolated from Geothermal Spring of Nepal JF - Journal of Food Science and Technology Nepal JA - J Food Sci Technol Nepal VL - 12 IS - 12 SE - Research Papers DO - 10.3126/jfstn.v12i12.31038 UR - https://nepjol.info/index.php/JFSTN/article/view/31038 SP - 49 - 58 AB - <p>A thermophilic amylolytic strain, <em>Anoxybacillus tengchongensis </em>RA1-2-1 was isolated from geothermal spring of Rasuwagadi district of Nepal. The BLAST alignment of the 16s rRNA sequence revealed 99.3% similarity with the type strain <em>Anoxybacillus tengchongensis </em>T-11. The morphological, physiological and biochemical properties were similar to the type strain. The enzyme from the strain was purified to 40-fold purification by DEAE-cellulose ion exchange chromatography. The K<sub>m</sub> value of the enzyme was 0.68±0.05 mg/ml. The optimum pH and temperature were 7.0 and 70 °C. SDS-PAGE analysis showed a single band at 69 kDa. The half-life of the enzyme at 70°C and 80°C were 85.01min and 51.96 min respectively. TLC analysis of the hydrolysis product showed that the enzyme is maltogenic amylase. The calcium independent enzyme was completely inhibited by Hg<sup>2+</sup> but showed inhibitory effect in the range of 100 %-30 % in the presence of other salts at 1-10 mM concentrations.</p> ER -