Purification of beta-glucosidase from Malatya apricot (Prunus armeniaca L.) seeds and some of its biochemical properties

Abstract

Introduction:b-Glucosidases are one of the key enzymes in car-bohydrate metabolism and located in glycosyl hydrolases (EC3.2.1) family. Plantb-glucosidases have biotechnological signifi-cance as they are effective on glycosidic bonds of flavor andaroma precursors in plants.b-Glucosidases that located in fruitseeds are important because they affect the amygdalin. Aim ofthis study is purification and partially characterization ofb-glu-cosidase from Malatya apricot seeds.Materials and methods:Apricot seeds were homogenized withextraction buffer to prepare of crude extract. The enzyme proteinwas precipitated with 60% ammonium sulfate then purified byhydrophobic interaction chromatography using Sepharose 4B-L-tyrosine-1-naptylamine gel.para-Nitrophenylb-D-glucopyrano-side (p-NPGlc) was used as substrate to determine biochemicalproperties of the enzyme. The optimum pH was determined usingbuffers between pH 2–12 and thermal optima was determinedusing 25–85°C temperature range. Inhibitory effects was deter-mined with 1 mM substances.Results:The enzyme was 11.1-fold purified with yield of 14%.Purifiedb-glucosidase from apricot seed was visualized about60 kDa molecular weight on SDS-PAGE. The kinetic parameterswere determined againstp-NPGlc substrate as Km and Vmaxvalues of 2.5 mM and 58.1 EU, respectively. The optimum pHand temperature were determined 5.0 and 55°C respectively.Effects of CaCl2, KCl, NaCl, MgCl2,K2SO4,Na2SO4, CuSO4,FeCl3, Pb(II) acetate, AgNO3, ZnCl2and glucose on purifiedenzyme activity were investigated. KCl, Na2SO4,Pb(II) acetatand CuSO4reduced the enzyme activity.Discussion and conclusion:In this study,b-glucosidase waspurified from Malatya apricot seed and some of its biochemicalproperties were determined. Because this enzyme has pharmaceu-tical importance hydrolyzing amygdalin. The results showed thatimmobilized almondb-glucosidase was used to break amygdalinand release -CN compound that effective to shrink cancer mass.