沙田柚皮水溶性多糖的提取和测定

柚皮细颗粒样品经石油醚回流脱脂、热水提取,以葡萄糖为参照品,利用分光光度法测定沙田柚皮中水溶性多糖的含量。葡萄糖浓度在15.0～100.0μg/ml范围内与吸光度有良好的线性关系,回归方程为:A=0.00755X+0.07475(r=0.9992),测出柚皮中水溶性多糖含量是7.28%,精密度为0.82%(n=3);对照实验的回收率为99.00%±1.15%,精密度为0.59%(n=5)。此法操作简便,结果稳定可靠,是柚皮及其果肉中水溶性多糖含量测定的有效方法。

Extraction and Determination of Water-soluble Polysaccharides from Peels of Grapefruit Planted in Sand-soil

Water-soluble polysaccharides in grapefruit peels were extracted with hot water and deposited with ethanol after removal of its impurities by refluxing with petroleum ether. Glucose was used as reference in the preparation of calibration curve. The content of water-soluble polysaccharides determined by spectrophotometry was 7.28% with 0.82% RSD(n=3). Good linearity ranged from 15.0μg/ml to 100.0μg/ml. The linear regression equation was as follows: A=0.00755X+0.07475(r=0.9992), Percent recovery of glucose from control experiment was 99.00%±1.15% with 0.59% of RSD(n=5). This method was proved to be simple, reliable and steady with reproducibility and convenient in operation. It can be used for the determination of polysaccharides in pees and pulp of grapefruit.