摘要
低档绿茶加热水浸提,再用少量有机溶剂萃取,后经硅胶柱层析分离,获得儿茶素的主要单体,经红外、紫外光谱鉴定,得到的单体是(—)—ECCG。将精制的儿茶素类、(—)—EGCG和没食子酸丙酯,添加到花生油中试验比较它们的抗氧化性。结果表明,抗氧化性大小与试验温度、添加剂的量有关。室温下,在花生油中相对添加量为0.4g/L的儿茶素,经277天的试验观察,氧化抑制率高达68.3％。
Low-quality green tea was extracted with hot water and organic solvent to obtain crude catechin mixture.The main tea catechin component(—)—epigallocatechin gallate(EGCG)was isolated by column chromatography and detected by infra—red spectrometry and ultraviolet spectrometry.Three samples,i,e.purified catechins:(—)—EGCG and propyl gallate were tested in peanut oil for their an- tioxidative aclivity.The results suggest that their antioxidative activity was related to their incorporate quantity and the experimental temperature.Under room temperature,when purified catechins were in- corporate into peanut oil(0.4g/L),their oxidation inhibition rate was 68.3%.Our result was obtained after 277 days observation.
关键词
绿茶
儿茶素
氧化还原反应
柱色谱
column chromatography
green tea
catecbins
oxido-reduction
