Functional substance search of horticultural products and research of the action mechanism of a functional substance

二氢吡嗪(DHP)物种包含在美拉德反应中间体中。美拉德反应被认为在衰老和糖尿病的病理生理学中发挥了作用。因此，DHP可能与衰老和糖尿病相关的疾病有关，然而，关于DHP的生物学和生理学作用的报道很少。此外，多酚类物质(POPs)作为植物体内的一种次生代谢物，具有多种生理功能，在人体营养中发挥着重要作用。利用大肠杆菌突变株，我们观察到与野生型菌株相比，环己基-DHP暴露显著降低了胞质十二烷基硫酸钠(SODA)缺陷菌株的存活率，显著降低了DNA修复缺陷菌株(recA和uvrB)的存活率，并轻度降低了过氧化氢酶缺陷菌株(Kate KatG)的存活率。加入Cu2+可提高环己基DHP的细胞杀伤力。在苏打菌株中，环己基-DHP诱发突变的频率随剂量增加而增加。此外，环己基-DHP提高了E caoli中蛋白质的羰基水平。我们研究了从甘薯叶中分离出的酚类化合物对选定的人癌细胞增殖的抑制作用。咖啡酸、二和三咖啡酰奎宁酸呈剂量依赖性抑制癌细胞的增殖，并观察到咖啡酰奎宁酸衍生物对各种癌细胞的敏感性差异。具体地说，3，4，5-三-O-咖啡酰奎宁酸能有效地抑制三种癌细胞的生长，其中咖啡酸对人早幼粒细胞白血病细胞(HL-60)的抑制作用高于其他二咖啡酰奎宁酸和三咖啡酰奎宁酸。

Dihydropyrazine (DHP) species are included in the Maillard reaction intermediates. The Maillard reaction is thought to play a role in the pathophysiology of aging and diabetes. Thus, DHP may be involved in aging and diabetes related diseases, however, there is little reported the biological and physiological roles of DHPs. Moreover, polyphenolics(POPs) as a secondary metabolite in plant, have various physiological functions and play important roles in human nutrition. By using Escherichia coli mutant strains, we observed that cyclohexyl-DHP exposure strongly reduced the survival rate of a cytosolic sodium dodecyl sulfate (SOD)-deficient strain (sodA sodB), significantly reduced the survival rates of DNA repair-deficient strains (recA and uvrB) and mildly reduced the survival rate of a catalase-deficient strain (katE katG) compared with the survival rate of the wild-type strain. Addition of Cu(2+) enhanced the cell killing ability of cyclohexyl-DHP. The frequency of mutations induced by cyclohexyl-DHP increased dose-dependently in the sodA sodB strain. Moreover, cyclohexyl-DHP elevated the protein carbonyl levels in E caoli. We investigated the suppression of the proliferation of selected human cancer cells by phenolic compounds isolated from sweetpotato leaf. Caffeic acid and di-and tricaffeoylquinic acids dose-dependently depressed cancer cell proliferation, and the difference in sensitivity between caffeoylquinic acid derivatives and each kind of cancer cell was observed. Specifically, 3,4,5-tri-O-caffeoylquinic acid effectively depressed the growth of three kinds of cancer cells, and caffeic acid had an exceptionally higher effect against romyelocytic leukemia cells (HL-60) than other di- and tricaffeoylquinic acids.