摘要
用分光光度计法在波长420nm下,以邻苯二酚为底物研究了兰州百合鳞茎中多酚氧化酶(Polyphenoloxidase,PPO)的部分特性。实验发现百合PPO的活性在4～25℃时,随着温度的升高而升高,25℃时PPO活性达到最大值,之后PPO活性随着温度的升高而下降;百合PPO有两个最适pH,分别为4.0和6.0,当pH低于4.0、高于6.0时活性均较低。抗坏血酸、异抗坏血酸钠、半胱氨酸在实验用的五种抑制剂中对PPO的抑制作用最强。
The activity of PPO was determined by spectrophotometer at 420nm using pyrocatechol as substrate.The effects of temperature, pH and inhibitors were studied. The results showed that the activity of PPO could be inhibited at a temperature higher than 25℃ and the optimum storage temperature was below 10℃.There were two optimum pH,4.0 and 6.0. Inhibitors such as cysteine, ascorbic acid and sodium isoascorbate could inhibit the enzyme activity effectively.But EDTA and citric acid had less effect on inhibiting enzyme activity.
出处
《食品工业科技》
CAS
CSCD
北大核心
2010年第4期166-168,共3页
Science and Technology of Food Industry
基金
中国农业大学URP计划
关键词
多酚氧化酶
酶促褐变
活性
polyphenoloxidase
enzymatic browning
enzyme activity
