An antioxidant rich novel β-amylase from peanuts (Arachis hypogaea): Its purification, biochemical characterization and potential applications

Abstract

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 361 μmol/min/mg protein. The enzyme was purified employing simple purification techniques for biochemical characterization. The purified enzyme was identified as β-amylase with Mr of 31 kDa. The enzyme displayed its optimum catalytic activity at pH 5.0 and 60 °C with activation energy of 4.5 kcal/mol and Q10 1.2. The enzyme displayed Km and Vmax values, for soluble potato starch of 1.28 mg/mL and 363.63 μmol/min/mg, respectively. Thermal inactivation of β-amylase at 65 °C resulted into first-order kinetics with rate constant 0.0126 min− 1 and t½ 55 min. 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. © 2018 Elsevier B.V.