苹果果胶酯酶提取及其酶学性质探究

以国光苹果为原料,通过单因素和正交实验考察了Na Cl浓度、p H、提取温度和提取时间对苹果果胶酯酶酶活的影响,确定了苹果果胶酯酶最佳提取工艺参数,并研究了苹果果胶酯酶的酶学性质。结果表明:在Na Cl浓度为2.5mol/L、p H为8.5、提取温度30℃和提取时间为27h时,苹果果胶酯酶的酶活达到0.98μmol/min·m L;该酶反应的最适温度为40℃,热稳定性较差,最适p H为11;金属离子中Ca2+对果胶酯酶有显著的激活作用,Na+、K+和Fe2+也有一定的激活作用,而Ba2+、Mn2+和EDTA对果胶酯酶有抑制作用。 

Extraction and enzyme properties of pectinesterase from apple

The optimal extraction condition of pectinesterase from apple was studied. Through single factor and orthogonal experiment, Na Cl solution concentration, p H, extraction temperature and time were investigated, and the enzyme properties from apple were also studied in this article. The results showed that:under the conditions of Na Cl solution concentration 2.5mol/L, p H8.5, extraction temperature 30℃, extraction time 27 h, pectinesterase activity could reach 0.98μmol/min·m L. The optimal temperature and p H of pectinesterase was 40℃ and 11, respectively. Its temperature stability was poor. Metal ions such as Na+, Ca2 +, K+, Fe2 +could stimulate pectinesterase activity, especially Ca2+was more remarkable stimulation than others. Ba2+, Mn2+and EDTA were inhibitors of pectinesterase activity.