荔枝果皮花青苷合成与相关酶的关系研究

以‘妃子笑’荔枝为试材,研究果实成熟过程中,果皮中花青苷含量及其生物合成相关的苯丙氨酸解氨酶(PAL)、查儿酮异构酶(CHI)、二氢黄酮醇还原酶(DFR)和类黄酮糖基转移酶(UFGT)的酶活性变化,同时研究套袋和生长调节剂对花青苷合成和相关酶活性的影响。结果表明,在4种酶中只有UFGT活性与荔枝果皮花青苷合成关系密切。UFGT活性的变化与花青苷含量的变化趋势吻合;随着‘妃子笑’果皮中UFGT活性的增加,花青苷含量上升;套袋处理抑制UFGT活性的同时也抑制花青苷的合成,除袋后UFGT活性和花青苷含量都迅速增加;6-BA处理抑制UFGT酶活性的同时也抑制花青苷合成,ABA和茉莉酸处理提高了UFGT酶活性的同时也促进了花青苷的合成。

Studies on the Relationship Between Anthocyanin Biosynthesis and Related Enzymes in Litchi Pericarp

Changes in the level of anthocyanin and the activities of enzymes of anthocyanin biosynthesis including plenylalanine ammonia lyase (PAL), chalcone ismoerase (CHI), dihydroflavonol reductase (DFR) and UDP glucose-flavonoid-3- o-glycosyltranfe-rase (UFGT) were studied in the pericarp of litchi cv. Feizixiao. Bagging and growth regulator dipping treatments were conducted to manipulate anthocyanin synthesis and the activities of related enzymes. The results demonstrated that among these enzymes UFGT was closely related to the synthesis of anthocyanin and probably was the limiting factor regulating anthocyanin biosynthesis in litchi pericarp. The activity of UFGT was in parallel with the changes of anthocyanin concentration. Bagging treatment inhibited the activity of UFGT as well as anthocyanin synthesis, whereas debagging enhanced both the activities of UFGT and anthocyanin synthesis. 6-BA dipping inhibited the synthesis of anthocyanin as well as the activity of UFGT, while ABA and jasmonic acid dipping accelerated the synthesis of anthocyanin paralleled the increase of the activity of UFGT.