植物源多酚氧化酶氧化儿茶素形成茶黄素和聚酯型儿茶素的研究

薛金金; 尹鹏; 张建勇; 王伟伟; 陈琳; 苏威; 郭桂义; 江和源

doi:10.13386/j.issn1002-0306.2019.20.013

植物源多酚氧化酶氧化儿茶素形成茶黄素和聚酯型儿茶素的研究

Screening of Plant-derived Polyphenol Oxidase for the Formation of Theaflavins and Theasinensins from the Oxidation of Catechins

摘要

摘要: 目的:筛选出催化儿茶素氧化形成TFs和TSs的最佳酶源。方法:以丰水梨、贡梨、香梨、红富士苹果、茶鲜叶、漆酶等作为试验材料,研究不同来源PPO酶活性,并比较其对TFs和TSs合成的影响。结果:丰水梨PPO酶活性最高,为621.4 U/(min·g),是茶鲜叶酶活性的2.8倍。PPO合成TFs能力及质量浓度从大到小依次为丰水梨(0.228 mg/mL)、红富士苹果(0.011 mg/mL)、漆酶(0.008 mg/mL),其中丰水梨PPO有利于TF-3'-G和TFDG的合成,而其他PPO则有利于TF的合成;PPO合成TSs能力及质量浓度从大到小依次为:丰水梨(0.958 mg/mL)、漆酶(0.158 mg/mL)、红富士苹果(0.100 mg/mL),丰水梨PPO有利于TSA和TSB的合成,红富士苹果PPO、漆酶则有利于TSA和TSC的合成;在丰水梨、红富士苹果、漆酶这3种酶的催化作用下,TSs的合成量均高于TFs。结论:丰水梨PPO具有比红富士苹果、漆酶更强的合成TFs和TSs的能力。

Abstract: Objective:To find the plant-derived PPO which can oxidize catechins to form TFs and TSs efficiently. Methods:Fengshui pear,Gong pear,Xiang pear,Hongfushi apple,tea fresh leaves and laccase were selected as the tested materials to study the PPO activity of different source. Effects of the PPO from Fengshui pear,Hongfushi apple,laccase on the synthesis of TFs and TSs from catechins were analysed. Results:The PPO in Fengshui pear had the highest activity which was 621.4 U/(min·g),approximately 2.8 times of that in fresh tea leaves. The ability to synthesis of TFs was Fengshui pear > Hongfushi apple > laccase. And concentrations of TFs were 0.228,0.011 and 0.008 mg/mL,respectively. TF-3'-G and TFDG were the major oxidation production with PPO of Fengshui pear. However,the other two PPO were contributed to the formation of TF. Meanwhile,the ability to synthesis of TSs was Fengshui pear > laccase > Hongfushi apple. And the concentrations of TSs were up to 0.958,0.158 and 0.100 mg/mL,respectively. The Fengshui pear PPO was contributed to the formation of TSA,TSB,while the other two PPO were contributed to the formation of TSA,TSC. Under the catalysis of three kinds of enzymes,the concentrations of TSs were all higher than TFs. Conclusion:The PPO in Fengshui pear had the stronger ability to synthesis of TFs and TSs than PPO from Hongfushi apple and laccase.