Chen Lirong, Guo Yuqiu, Li Xiaoyue, Gong Kuijie, Liu Kaichang
Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China.
BMC Chem. 2021 Mar 1;15(1):14. doi: 10.1186/s13065-021-00740-7.
The polyphenol distribution in fresh waxy corns of different color varieties and their functional activities, which may be useful for treating various chronic diseases, were investigated. The in vitro antioxidant activity, and hypoglycemic and hypocholesterolemic effects of the free and bound corn phenolics were determined to evaluate the edible value of fresh waxy corn. The colored varieties contained more phenols than the common varieties (white and/or yellow). The total free phenolic acid content of the six varieties was 6637.73 µg/g DW (dry weight), which was slightly higher (P > 0.05) than that of the total bound form (6276.65 µg/g DW). The total free flavonoid content was 5850.09 µg/g DW, which was higher (P < 0.05) than that of the total bound form (4874.51µg/g DW). No bound anthocyanin was detected in the methanol extracts of the tested varieties. For all the varieties, free polyphenols contributed 86-100 % and 70-78 % of the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical scavenging abilities, respectively, and 100 % of the ferric reducing capacity. The free phenolics in fresh waxy corn showed better (P < 0.05) hypoglycemic effect than the bound form in terms of inhibition of α-amylase activity, whereas the bound phenolics of most varieties showed higher α-glucosidase inhibitory activity than the free forms. The free phenolics showed better (P < 0.05) glycocholesterol binding than the bound form for all varieties. The bound polyphenols showed better sodium cholate and taurocholate binding than the free form for most varieties. In conclusion, the difference between free and bound polyphenol content and functional activities indicates that fresh waxy corn can be potentially used for the development of functional food.
研究了不同颜色品种鲜糯玉米中的多酚分布及其功能活性，这些功能活性可能对治疗各种慢性疾病有用。测定了游离态和结合态玉米酚类物质的体外抗氧化活性、降血糖和降胆固醇作用，以评估鲜糯玉米的食用价值。有色品种比普通品种（白色和/或黄色）含有更多的酚类物质。六个品种的总游离酚酸含量为6637.73μg/g干重，略高于总结合态（6276.65μg/g干重）（P>0.05）。总游离黄酮含量为5850.09μg/g干重，高于总结合态（4874.51μg/g干重）（P<0.05）。在所测试品种的甲醇提取物中未检测到结合态花青素。对于所有品种，游离多酚分别占2,2-二苯基-1-苦基肼（DPPH）和羟基自由基清除能力的86-100%和70-78%，以及铁还原能力的100%。在抑制α-淀粉酶活性方面，鲜糯玉米中的游离酚类物质比结合态表现出更好的（P<0.05）降血糖作用，而大多数品种的结合酚类物质比游离态表现出更高的α-葡萄糖苷酶抑制活性。对于所有品种，游离酚类物质比结合态表现出更好的（P<0.05）胆甾醇结合能力。对于大多数品种，结合多酚比游离态表现出更好的胆酸钠和牛磺胆酸钠结合能力。总之，游离态和结合态多酚含量及功能活性的差异表明鲜糯玉米有潜力用于功能性食品的开发。
