论文部分内容阅读
从鸭梨中提取的多酚氧化酶及其天然底物,两者能相互作用,形成褐色产物。加抑制剂则褐变被抑制,说明酶促褐变是鸭梨黑心病发病的主要原因。分析表明,鸭梨果心有较高的底物含量,约为果肉的2.7倍。鸭梨褐变一般从果心开始发展到果肉,与酚类含量有关。贮藏期间果心酚类底物含量在褐变初期都有一个高峰值,而褐变鸭梨的果心组织酚类含量常小于未褐变的鸭梨。同时多酚氧化酶的活力在同期相应呈现出明显的高峰。这进一步说明鸭梨褐变是以酚类底物消耗、在多酚氧化酶催化下进行的生化反应。将鸭梨果心酚类物质分离提纯后进行纸层析、紫外扫描、红外光谱鉴定,确认为绿原酸。
Polyphenol oxidase extracted from pear and its natural substrate, the two can interact to form a brown product. Inhibition of browning was inhibited, indicating that enzymatic browning is the main cause of black pear heart disease. Analysis shows that pear fruit has a higher substrate content, about 2.7 times the pulp. Pear browning generally develops from the fruit heart to the pulp, and the content of phenols. During the storage period, the content of phenolic substrate in the heart of the browning had a peak value in the early stage of browning, while the phenolic content in the heart tissue of the browning pear was always less than that of the non-browning pear. At the same time, the activity of polyphenol oxidase showed a corresponding peak at the same period. This further shows that the pear browning is phenolic substrate consumption, the polyphenol oxidase catalytic biochemical reactions. The pear heart phenolics were isolated and purified by paper chromatography, UV scanning, infrared spectroscopy identification, identified as chlorogenic acid.