【摘要】 从中药马槟榔(Capparis masaikai Levl.)成熟种子中分离了一种能引起持久甜味的蛋白质,取名为马槟榔甜蛋白(Mabinlin),分子量11,700,等电点pH11.8,在280nm波长有最大吸收峰,其引起甜味感觉的最低浓度为0.1％,种仁含甜蛋白量约4％。更多还原

【Abstract】 Capparis masaikai Levl. with a native name Mabinlang is distributed in Yunnan of China. Its mature seeds are used as chinese medicine and possess sweet taste. The sweet principle has been established to be a basic protein, herein named mabinlin. The protein is extracted from lipid-free seed powder with water at 45℃, and precipitated with 60% saturation of (NH4)2SO4 at pH7, and then precipitated with 2 volumes of acetone from the dialyzed aqueous solution of protein. The solid albumin preparation contains 16,5% of N, and its yield is about 7.2% on dry weight of decorticated seeds. It contains four protein components A, B, C, D with relative mobility of 0.46, 0.51, 0.73 and 0.89 respectively in 15% polyacylamide gel electrophoresis (pII 4.3). These components are separated from each other by using CM-sephadex c-50 column chro-matography and hydroxyapatite column chromatography. Only the component D tastes sweet. Its isoelectric point is about pH 11.8, estimated by using electricfocusing and precipitation of a 0.1% protein solution at different pH. Its molecular weight is about 11700, estimated by using SDS-polyacrylamide gel electrophoresis. No carbohydrate (<7μg/mg protein) could be detected. Its aqueous solution can elicit a persist ent swee.t taste, and the lowest concentration eliciting sweet is about 0.1%.更多还原