【摘要】 果胶酯酶(PE或PME)能催化果胶脱酯生成低酯果胶和果胶酸,属于一类果胶酶,广泛应用于食品特别是果品加工工业中。以新鲜柠檬为原料,采用NaCl-冷冻离心-盐析的方法提取柠檬果实中的果胶酯酶,pH-stat法对果胶酯酶进行活性分析。研究温度、pH、相对储藏度等因素对柠檬类果实果胶酯酶的活性影响,并探索该酶的最适温度、最适pH值,进而研究该酶的热稳定性;对柠檬果实中果胶含量进行测定。实验表明:58℃,pH=6.90时柠檬中的果胶酯酶的活力最高。更多还原

【Abstract】 Pectinesterase,one kind of pectinase,is called PME or PE for short.It has the ability to take off the methoxyl group from pectin and make it become pectic acid. It uses extensively in the food industry,especially in the fruit packing industry. Taking fresh lemon as raw material in the ,adopt NaCl solvent extraction and refriferational centrifugation to take out the row enzyme,and then using(NH4)2SO4 solution to salting out the other enzyme, after improving the pH-stat method(Z.I.Kertesz,1937), carry on live analysis to the lemon’s PE. Studied the influence factors of temperature,pH value,relative reposition etc. to the lemon’s PE,and investigated the most suitable temperature,pH value of that enzyme,then studied the hot stability of it.It showed that the optimum condition was T=58 ℃ and pH=6.90.更多还原