A methanol extract of red pepper showed potent acetyl-CoA carboxylase inhibitory activity. The active principles were isolated and identified as (E, E)- and (E, Z)-9-oxooctadeca-10,12-dienoic acids by instrumental analyses. The IC50 values of the compounds were 1.4×10(-6) and 1.5×10(-6) M, respectively, their activity being nearly sixty-times higher than that of the common fatty acids themselves. A comparative study of the structure-activity relationship among their related compounds showed that the inhibitory activity was influenced neither by the position and species of the oxygen functional group in the middle of the alkyl chain nor by the configurations of the double bonds. However, it was found that the presence of double bonds between the terminal carboxyl and the mid-chain oxygen functional group lowered the inhibitory activity which could be recovered by hydrogenation of the double bonds.

中文翻译：

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9-Oxooctadeca-10,12-二烯酸作为红辣椒（Capsicum annuum L.）的乙酰辅酶A羧化酶抑制剂。

红辣椒的甲醇提取物显示出有效的乙酰辅酶A羧化酶抑制活性。通过仪器分析分离了活性成分并鉴定为（E，E）-和（E，Z）-9-氧代十八烷基-10，12-二烯酸。这些化合物的IC50值分别为1.4×10（-6）和1.5×10（-6）M，其活性是普通脂肪酸自身的近60倍。对其相关化合物之间的构效关系的比较研究表明，抑制活性既不受烷基链中间氧官能团的位置和种类的影响，也不受双键构型的影响。然而，