玉米籽粒发芽过程中不同部位类胡萝卜素合成动态及抗氧化活性

The Synthesis Dynamics of Carotenoids and Antioxidant Activity in Different Parts of Maize Kernel during Germination

本研究以黄玉米种子为原料,研究其在发芽过程中种胚、胚芽和胚根中总类胡萝卜素、叶黄素和玉米黄质的合成动态以及抗氧化活性。结果表明:玉米籽粒的发芽率随着发芽时间的延长而增加,在12~36 h间是玉米籽粒的出芽时间。玉米籽粒发芽过程中种胚、胚根和胚芽的鲜重呈现上升趋势,且种胚鲜重>胚芽鲜重>胚根鲜重。随着发芽时间的增加,种胚和胚根的总类胡萝卜素积累量增加,而胚芽中的总类胡萝卜素积在36~48 h和60~72 h增加极为显著。种胚、胚根和胚芽中主要类胡萝卜素物质以叶黄素为主,胚芽的总类胡萝卜素含量明显高于胚根和种胚。玉米籽粒发芽72 h时总类胡萝卜素含量为发芽前的6.19倍。同时,胚芽和种胚中的抗氧化活性随着发芽时间的增加而升高,最高分别达到了8.01μmol TEAC/g和8.51μmol TEAC/g,胚根则相反。故发芽可以显著提高玉米籽粒中不同部位的类胡萝卜素含量及胚芽的抗氧化活性。

Yellow maize kernels were used as the raw materials in this study.The synthesis dynamics of total carotenoids,lutein and zeaxanthin as well as the antioxidant activity in embryos,germs and radicles were investigated during germination.The results showed that the germination rate of corn kernels increased with the germination time,and the germination time of corn kernels was between the 12th and 36th h.During germination,the fresh weight of embryo,radicle and germ showed an upward trend,following the decreasing order of the embryo,followed by embryo>germ>radicle.With the increase of germination time,the total carotenoids accumulated in the embryo and radicle increased,whilst the total carotenoid accumulation in the germ increased significantly at 36 th^48 th h and 60 th^72 th h.The main carotenoid in the embryo,radicle and germ was lutein,and the total carotenoid content in the germ was significantly higher than those in the radicle and embryo.The total carotenoid content of corn kernels after germination for 72 h was 6.19 times that before germination.At the same time,the antioxidant activity in germ and embryo increased with the germination time,with the highest reaching 8.01μmol TEAC/g and 8.51μmol TEAC/g,respectively.However,an opposite trend was for the radicle.Therefore,germination can significantly increase the carotenoid content in different parts of the maize kernels and the antioxidant activity of the germ.