Analkali tolerant α-l-rhamnosidase has been purified to homogeneity from the culture filtrate of a new fungal strain, Fusarium moniliforme MTCC-2088, using concentration by ultrafiltration and cation exchange chromatography on CM cellulose column. The molecular mass of the purified enzyme has been found to be 36.0 kDa using SDS-PAGE analysis. The Km value using p-nitrophenyl-α-l-rhamnopyranoside as the variable substrate in 0.2 M sodium phosphate buffer pH10.5 at50 °C was 0.50 mM. The catalytic rate constant was15.6 s-1giving the values of kcat/Km is 3.12 × 104M-1 s-1. The pH and temperature optima of the enzyme were 10.5 and 50 °C, respectively. The purified enzyme had better stability at 10 °C in basic pH medium. The enzyme derhamnosylated natural glycosides like naringin to prunin, rutin to isoquercitrin and hesperidin to hesperetin glucoside. The purified α-l-rhamnosidase has potential for enhancement of wine aroma.

中文翻译：

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来自镰刀镰孢MTCC-2088的耐碱α-1-鼠李糖苷酶，用于天然糖苷的鼠李糖基化。

使用超滤浓缩和阳离子交换色谱法在CM纤维素柱上进行浓缩，已从新真菌菌株Monsarforme MTCC-2088的培养滤液中纯化了耐碱的α-1-鼠李糖苷酶。使用SDS-PAGE分析发现纯化的酶的分子量为36.0kDa。在50℃下在0.2M磷酸钠缓冲液pH10.5中使用对硝基苯基-α-1-鼠李糖吡喃糖苷作为可变底物的Km值为0.50mM。给出的kcat / Km值为3.12×104M-1 s-1，催化速率常数为15.6 s-1。该酶的最适pH和最适温度分别为10.5和50°C。纯化的酶在碱性pH介质中于10°C时具有更好的稳定性。derhamnosylated的天然糖苷酶，如柚皮苷到李宁，芦丁到异槲皮苷，橙皮苷到橙皮苷葡萄糖苷。