由草莓粕製備鞣花酸濃縮物方法之探討

Abstract

鞣花酸（ellagic acid）是一種廣泛存在於許多漿果類水果中的多酚類化合物，已有許多研究證實鞣花酸之生理活性，包括抗氧化力、抑制癌細胞增生、誘導癌細胞凋亡等。本研究以釀製草莓酒的廢棄物---草莓粕為原料，發展簡便回收鞣花酸的製作程序，製得高濃度的鞣花酸濃縮物。在試驗中將草莓粕以1N HCl在85℃下水解3小時，原料中的鞣花單寧（ellagitannins）可水解釋出鞣花酸，此步驟使原樣品中的鞣花酸的含量由每克乾重2.3 mg增加到14.9 mg，酸水解後的樣品再經過乙酸乙酯處理除去疏水性的成分，之後將樣品以25倍體積的甲醇在室溫下震盪萃取1小時，所得萃取液加蒸餾水調成25%的甲醇水溶液，直接通入疏水性層析管柱HP-20，在流洗液中逐步增加甲醇濃度，並檢測流出液中鞣花酸的分佈情形。此製程的終產物鞣花酸純度可達80%以上，整體純化過程鞣花酸的回收率約47%。

Ellagic acid, a phenolic compound extensively existing in many kinds of berry, has been reported to possess some physiological activities such as antioxidative, antiproliferative activities, and apoptosis inducing ability. The aim of this research was to develop a simple and rapid procedure to recover ellagic acid from the strawberry pomace of strawberry liquor manufacturing. First of all, strawberry pomace was hydrolyzed to release the free form of ellagic acid by 1N HCl at 85℃ for 3 h. This process hydrolyzed ellagitannins effectively and increased ellagic acid content from 2.3 mg/g to 14.9 mg/g. After hydrolysis, the sample was washed with ethyl acetate to remove the hydrophobic components of sample and then extracted occasionally shaking with 25-fold volume of methanol at room temperature for 1h. Three-fold volume of distilled water was added into the extract to make a 25% Methanol solution, which was then subjected into a hydrophobic HP-20 column. The separation was conducted by eluting the column with increasing the content of methanol in the mobile phase. The eluates were collected by a fraction collector. The fraction with most abundant of ellagic acid were pooled and the recovery was calculated. According to the present, concentrated ellagic acid final product could be obtained easily, and the content of ellagic acid was more than 80%, and overall, this separated process could recover 47% of ellagic acid from the raw strawberry pomace.