Bleaching Activity of 4-Phenyl-3-(substituted benzylthio)-4<i>H</i>-1,2,4-triazoles
作者:Naotaka YAMADA、Daisuke KUSANO、Eiich KUWANO
DOI:10.1271/bbb.66.1671
日期:2002.1.1
A variety of 4-aryl- and 4-alkyl-3-(substituted benzylthio)-4H-1,2,4-triazoles were prepared and evaluated for their bleaching activity by the lettuce seedling test. Among the series of tested compounds, 4-(3-fluorophenyl)-3-(4-trifluoromethylbenzylthio)-4H-1,2,4-triazole (39) exhibited the highest bleaching activity, causing complete bleaching symptoms at 10 μM. In the dark condition, compound 39 inhibited the formation of such carotenoids as β-carotene, violaxanthin, neoxanthin and lutein, resulting in the formation of ζ-carotene, phytoene, phytofluene and β-zeacarotene, which were not detected in the untreated control. Treatment by compound 39 at 50 μM resulted in the amount of accumulated ζ-carotene being seven-fold higher than that of phytoene, phytofluene and β-zeacarotene. These results suggest that compound 39 might have interfered with desaturation, especially ζ-carotene desaturation, during carotenoid biosynthesis.
制备了多种 4-芳基和 4-烷基-3-(取代苄硫基)-4H-1,2,4-三唑,并通过莴苣幼苗试验评估了它们的漂白活性。在一系列测试化合物中,4-(3-氟苯基)-3-(4-三氟甲基苄硫基)-4H-1,2,4-三唑(39)表现出最高的漂白活性,在 10 μM 时可引起完全漂白症状。在黑暗条件下,化合物 39 可抑制类胡萝卜素(如 β-胡萝卜素、violaxanthin、neoxanthin 和叶黄素)的形成,导致 ζ-胡萝卜素、phytoene、phytofluene 和 β-玉米赤霉烯类的形成,而在未处理的对照组中检测不到这些类胡萝卜素。化合物 39 的浓度为 50 μM 时,ζ-胡萝卜素的累积量是植物烯、植物芴和β-玉米赤霉烯类的七倍。这些结果表明,化合物 39 可能干扰了类胡萝卜素生物合成过程中的脱饱和作用,尤其是ζ-胡萝卜素的脱饱和作用。