School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi 221005, India.
School of Biotechnology, Institute of Science, Banaras Hindu University, Varanasi 221005, India.
Int J Biol Macromol. 2018 May;111:148-157. doi: 10.1016/j.ijbiomac.2017.12.130. Epub 2018 Jan 3.
β-Amylase from un-germinated seeds of peanut (Arachis hypogaea) was purified to apparent electrophoretic homogeneity with final purification fold of 205 and specific activity of 361μmol/min/mg protein. The enzyme was purified employing simple purification techniques for biochemical characterization. The purified enzyme was identified as β-amylase with M of 31kDa. The enzyme displayed its optimum catalytic activity at pH5.0 and 60°C with activation energy of 4.5kcal/mol and Q 1.2. The enzyme displayed K and V values, for soluble potato starch of 1.28mg/mL and 363.63μmol/min/mg, respectively. Thermal inactivation of β-amylase at 65°C resulted into first-order kinetics with rate constant 0.0126min and t 55min. The enzyme was observed to act on native granular potato starch, which could minimize the high cost occurring from solubilization of starch in industries. Enzyme fractions scavenge 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical, indicating its antioxidative nature. In addition, the purified β-amylase was successfully utilized for the improvement of antioxidant potential of wheat. These findings suggest that β-amylase from peanuts have potential application in food and pharmaceutical industries.
从未发芽的花生(落花生)种子中纯化出的β-淀粉酶达到了明显的电泳均一性,最终纯化倍数为 205,比活为 361μmol/min/mg 蛋白。该酶采用简单的生化特性分析纯化技术进行了纯化。纯化后的酶被鉴定为β-淀粉酶,分子量为 31kDa。该酶在 pH5.0 和 60°C 下显示出最佳的催化活性,活化能为 4.5kcal/mol,Q 1.2。该酶对可溶性马铃薯淀粉的 K 和 V 值分别为 1.28mg/mL 和 363.63μmol/min/mg。β-淀粉酶在 65°C 下的热失活动力学呈一级反应,速率常数为 0.0126min,t 55min。该酶被观察到作用于天然颗粒状马铃薯淀粉,这可以最大限度地减少淀粉在工业中溶解所带来的高成本。酶级分清除 2,2-二苯基-1-苦基肼(DPPH)自由基,表明其具有抗氧化性质。此外,纯化的β-淀粉酶成功地用于提高小麦的抗氧化能力。这些发现表明,花生中的β-淀粉酶在食品和制药工业中有潜在的应用。