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多酚氧化酶(邻苯二酚:氧—氧化还元酶E.C.1·10·3·1),又称邻苯二酚氧化酶、甲基酚氧化酶、酪氨酸酶等,名称较多,依底物而异。1856年,Schoenbeim 首先于蘑菇中发现此酶,它在分子氧的存在下,使植物中某些化合物氧化。此酶广泛存在于各种植物中,如各种水果(桃、苹果、香蕉等),马铃薯,茶叶,咖啡豆,烟草叶等。此酶含铜,可酶促羟化及脱氢两种反应。不同来源及不同型式的酶,此二种活力的大小不同。酶促反应的机理已有多种论述。多酚氧化酶与植物的酶促褐变有极密切的关系。测定不同植物中的多酚氧化酶活力,可以对褐变作用进行比较研究,为阻止褐变(当褐变作用起不良效应时)或促进褐变(当褐
Polyphenol oxidase (catechol:oxygen-oxidant enzyme EC1·10·3.1), also known as catechol oxidase, methyl phenol oxidase, tyrosinase, etc. Depending on the substrate. In 1856, Schoenbeim first discovered this enzyme in mushrooms, which oxidized certain compounds in plants in the presence of molecular oxygen. This enzyme is widely found in a variety of plants, such as various fruits (peach, apple, banana, etc.), potatoes, tea, coffee beans, tobacco leaves and so on. This enzyme contains copper and can be enzymatically hydroxylated and dehydrogenated. Different sources and different types of enzymes, the two kinds of vitality are different in size. The mechanism of enzymatic reactions has been discussed extensively. Polyphenol oxidase is closely related to the enzymatic browning of plants. To determine the polyphenol oxidase activity in different plants, a comparative study of browning may be performed to prevent browning (when the browning effect is adverse) or to promote browning (when browning