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β-Glucosidases are important in the formation of floral tea aroma and the development ofresistance to pathogens and herbivores in tea plants.A novel β-glucosidase was purified 117-fold to homogeneity,with a yield of 1.26%.from tea leaves by chilled acetone and ammonium sulfate precipitation,ion exchangechromatography(CM-Sephadex C-50)and fast protein liquid chromatography(FPLC;Superdex 75,ResourceS).The enzyme was a monomeric protein with specific activity of 2.57 U/mg.The molecular mass of theenzyme was estimated to be about 41 kDa and 34 kDa by SDS-PAGE and FPLC gel filtration on Superdex200,respectively.The enzyme showed optimum activity at 50℃ and was stable at temperatures lower than40℃.It was active between pH 4.0 and pH 7.0,with an optimum activity at pH 5.5,and was fairly stablefrom pH 4.5 to pH 8.0.The enzyme showed maximum activity towards pNPG,low activity towardspNP-Galacto,and no activity towards pNP-Xylo.
β-Glucosidases are important in the formation of floral tea aroma and the development of resistance to pathogens and herbivores in tea plants. A novel β-glucosidase was purified 117-fold to homogeneity, with a yield of 1.26% .from tea leaves by chilled acetone and ammonium sulfate precipitation, ion exchange chromatography (CM-Sephadex C-50) and fast protein liquid chromatography (FPLC; Superdex 75, ResourceS). The enzyme was a monomeric protein with a specific activity of 2.57 U / mg. estimated to be about 41 kDa and 34 kDa by SDS-PAGE and FPLC gel filtration on Superdex 200, respectively. The enzyme showed optimum activity at 50 ° C and was stable at temperatures lower than 40 ° C. It was active between pH 4.0 and pH 7.0, with an optimum activity at pH 5.5, and was fairly stable from pH 4.5 to pH 8.0. The enzyme showed maximum activity towards pNPG, low activity towards pNP-Galacto, and no activity towards pNP-Xylo.