Department of Environmental Toxicology, University of California , Davis, California 95616, USA.
J Agric Food Chem. 2012 Jun 27;60(25):6260-7. doi: 10.1021/jf301700j. Epub 2012 Jun 18.
Saponarin, a flavonoid found in young green barley leaves, possesses potent antioxidant activities, which are determined by its inhibition of malonaldehyde (MA) formation from various lipids oxidized by UV light or Fenton's reagent. Lipids used were squalene, ethyl linoleate, ethyl linolenate, ethyl arachidonate, octadecatetraenoic acid (ODTA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), cod liver oil, lecithin I, lecithin II, and blood plasma. The addition of saponarin inhibited the formation of MA from squalene upon UV irradiation at the level of 2 μmol/mL by almost 100%, whereas BHT inhibited its formation by 75% at the same level. Saponarin showed potent antioxidant activity toward fatty acid ethyl esters at levels >100 μg/mL. Saponarin inhibited MA formation in ODTA by 60%, in EPA by 50%, and in DHA by 43% at the level of 15 μmol/mL. Saponarin exhibited strong antioxidant activities with dose-response levels toward cod liver oil and lipoproteins (lecithins I and II), higher than those of α-tocopherol. A mixture of saponarin/lutonarin (4.5:1, w/w) inhibited MA formation appreciably from all lipids tested with dose response. This mixture exhibited highest effect toward cod liver oil (86%), followed by DHA, lecithin II, blood plasma, EPA, and lecithin I. Supplementation of young green barley leaves containing saponarin should be beneficial to health and may prevent diseases caused by oxidative damage such as various cancers, inflammations, and cardiovascular diseases.
水飞蓟宾，一种在嫩麦苗叶中发现的类黄酮，具有很强的抗氧化活性，这是由其抑制由紫外线或 Fenton 试剂氧化的各种脂质形成丙二醛（MA）来决定的。所用的脂质有角鲨烯、亚油酸乙酯、亚麻酸乙酯、花生四烯酸乙酯、十八碳四烯酸（ODTA）、二十碳五烯酸（EPA）、二十二碳六烯酸（DHA）、鱼肝油、I 型卵磷脂、II 型卵磷脂和血浆。在紫外线照射下，当添加 2μmol/mL 的水飞蓟宾时，几乎可以抑制 100%的角鲨烯形成 MA，而 BHT 在相同水平下抑制其形成的程度为 75%。水飞蓟宾对脂肪酸乙酯的抗氧化活性在 >100μg/mL 的水平上表现出很强的活性。水飞蓟宾对 ODTA 形成 MA 的抑制率为 60%，对 EPA 为 50%，对 DHA 为 43%，在 15μmol/mL 的水平上。水飞蓟宾对鱼肝油和脂蛋白（I 型和 II 型卵磷脂）表现出很强的抗氧化活性，其剂量反应水平高于α-生育酚。水飞蓟宾/芦丁（4.5:1，w/w）混合物对所有测试脂质的 MA 形成均有明显的抑制作用，并具有剂量反应。该混合物对鱼肝油（86%）的效果最高，其次是 DHA、II 型卵磷脂、血浆、EPA 和 I 型卵磷脂。补充含有水飞蓟宾的嫩麦苗叶应该对健康有益，并可能预防由氧化损伤引起的各种疾病，如各种癌症、炎症和心血管疾病。
