Plant components modifies the absorption, metabolism and excretion of xenobiotics.

本研究从绿茶和海藻中分离出几种具有抗氧化、清除自由基和抗突变活性的有效成分。在体内和体外考察了这些成分对外源物质的吸收、代谢和排泄的修饰效力。生菜(Ulva Pertusa Kjellman)甲醇提取物的抗氧化活性在0.5~5.0 mg/ml范围内呈剂量依赖关系，但水提取物的抗氧化活性仅为甲醇提取物的20%。甲醇提取物对自由基的清除活性(ED_50)为0.7-1.6 mg/ml，并能抑制熟肉和鱼中形成的MelQx和Trp P-1的致突变性。绿茶提取物对亚硝基吗啉的致突变性有抑制作用(0.5 mg/皿为34%，1.0 mg/皿为70%)。绿茶提取物还能抑制亚硝酸钠和吗啡所致大鼠亚硝胺吗啡的形成。几种含有槲皮素和芦丁的黄酮类化合物以及甲壳素、壳聚糖和纤维素等食用纤维对具有致癌和内分泌干扰活性的DOT具有很强的吸附能力。通过改变吸收、代谢和排泄步骤，成为许多外来生物解毒的有益工具。

In this study several effective components were isolated from green tea and seaweeds, which show antioxidative, radical scavenging and antimutagenic activities. The modification potency of these components to absorption, metabolism and excretion of xenobiotics were examined in vivo and in vitro.1. The methanol extract of sea lettuce (Ulva pertusa kjellman) showed antioxidative activity in a dose dependent manner at the range of 0.5 to 5.0 mg/ml. But the potency of water extract was 20 % compared to that of the methanol extract. And radical scavenging activity (ED_50) of the methanol extract was 0.7-1.6 mg/ml. Moreover, the methanol extract inhibited the mutagenicity of MelQx and Trp P-1 which were formed in cooked meat arid fish.2. Green tea extract suppressed the mutagenicity of nitrosomorpholine (34% in 0.5 mg/plate, 70 % in l.0 mg/plate). Green tea extract also inhibited the formation of nitrosomorpholine in rat oral administered sodium nitrite and morpholine.3. Several flavonoids containing quercetin and rutin, and food fiber such as chitin, chitosan and cellulose showed the strong adsorption potency to DOT having carcinogenicity and endocrine disrupting activity.From these data, the intake of plant components including flavonoids may. be beneficial tool to detoxify many xenobiotics by modification of absorption, metabolism and excretion steps.