PLF对鲜切苹果保鲜及其机理的初步探讨

Fresh-keeping and mechanism of persimmon leaf flavonoids on fresh-cut apple

从Vc含量、TSS含量和褐变度3个指标综合考察了柿叶黄酮(PLF)对鲜切苹果的保鲜效果,并从PLF对酪氨酸酶的抑制和抗氧化性两个方面探讨了PLF对样品的保鲜作用机理。结果表明:当PLF浓度为0.1mg/mL、浸泡时间为5min时的保鲜效果最佳,PLF对酪氨酸酶具有一定的抑制作用,PLF对DPPH·、阴离子自由基(O-2·)和羟自由基·(OH)有较好的清除作用。实验结论:PLF对鲜切苹果片具有一定的保鲜效果;PLF对鲜切苹果片的保鲜作用与其对酪氨酸酶的抑制和对多种自由基的清除作用有关,这可能是PLF对苹果片具有保鲜作用的机理之一。

Fresh-keeping of persimmon leaf flavonoids（PLF） on fresh-cut apple was studied. The content of Vc and TSS,and the changes of browning degree of fresh-cut apple were studied during the storage. The mechanism of PLF on fresh-cut apple was studied from the inhibitory on tyrosinase activities and its oxidation resistance. The results showed that PLF showed good fresh-keeping when concentration of sample 0.1 mg/mL,soak time 5 min. PLF had obvious inhibitory activity on tyrosinase,had activity of scavenging DPPH·,O-2· and ·OH. Conclusion：PLF showed good fresh-keeping. The mechanism was related to its inhibitory on tyrosinase activities and its oxidation resistance. This is probably the PLF with preservation role of the mechanism.