发酵性丝孢酵母胞内脂肪酶与蛋白酶性质的研究

Characterization of lipase and protease from Trichosporon fermentans

为了探讨发酵性丝孢酵母胞内脂肪酶和蛋白酶的潜在应用,通过超声波破碎细胞获得胞内酶,研究了温度、pH、金属离子、有机溶剂、表面活性剂、蔗糖、淀粉、酪蛋白对粗酶液的酶活力的影响。研究结果表明,两种酶的最适反应条件均为55℃、pH中性;5 mmol/L的金属离子Ca^(2+)、Mn^(2+)降低了脂肪酶活力,而提高了蛋白酶的活力;20%(v/v)甲醇、乙醇、异丙醇、正己烷、甲苯对脂肪酶均具有激活作用,其中正己烷激活作用最大;而所试有机溶剂均严重抑制蛋白酶活力;0.01%(v/v)Triton X-100和蔗糖7.5%(w/v)对脂肪酶和蛋白酶均具有激活作用,0.5%(w/v)可溶性淀粉和1%~2.5%(w/v)酪蛋白均能提高脂肪酶活力且降低蛋白酶活力。这些特性使发酵性丝孢酵母胞内脂肪酶和蛋白酶应用于洗涤剂具有可能性。

For researching the potential application of intracellular lipase and protease from Trichosporon fermentans, the influences of temperature, pH, cations, organic solvents, surfactants, sucrose, starch and casein on activities of enzymes were studied. The intracellular enzymes were obtained by ultrasonieation. The results revealed that lipase and protease showed the maximum activities at 55℃ and neutral pH. The lipase activity was reduced while the protease activity could be partially increased by 5 mmol/L Ca2＋ and Mn2＋. The lipase was stimulated by 20% （v/v） methanol, ethanol, isopropanol, n-hexane and toluene, to the highest activity by n-hexane. And the protease was strongly inhibited by all the tested organic solvent. The activities of lipase and protease were increased in the presence of 0.01% （v/v） TritonX-100 and 7.5% （w/v） sucrose. It was revealed that 0.5% （w/v） amylodextrine and 1% -2.5% （w/v） casein could activate lipase but inhibit protease. These characteristics provided the potential application of the lipase and protease from Trichosporon fermentans in detergents.