Watanabe S, Yamaguchi M, Sobue T, Takahashi T, Miura T, Arai Y, Mazur W, Wähälä K, Adlercreutz H
Department of Nutritional Science, Tokyo University of Agriculture, Tokyo, Japan.
J Nutr. 1998 Oct;128(10):1710-5. doi: 10.1093/jn/128.10.1710.
To take advantage of the various pharmacologic activities of soy bean isoflavones, more detailed studies of the absorption and excretion rates of these compounds in humans and subsequent evaluation of their bioavailabilities are required. We conducted a pharmacokinetic study of soybean isoflavones in seven healthy male volunteers. After ingestion of 60 g of kinako (baked soybean powder, containing 103 micromol daidzein and 112 micromol genistein), changes of the isoflavone and metabolite concentrations in plasma, urine and feces were measured by gas chromatography-mass spectrometry. The plasma concentration of genistein increased after 2 h and reached its highest value of 2.44 +/- 0.65 micromol/L 6 h later. The plasma concentration of daidzein peaked at 1.56 +/- 0.34 micromol/L at the same time, but it was always lower than that of genistein. Peak plasma concentration of O-desmethylangolensin (O-DMA) and equol appeared after the daidzein peak in four and two subjects, respectively. In contrast with plasma, daidzein was the main component in urine. Urinary daidzein excretion started to increase shortly after the rise in its plasma concentration and reached 2.4 micromol/h 8 h after ingestion of kinako. Genistein excretion in urine paralleled that of daidzein, but the value at 6 h was about half (1.1 micromol/h). The majority of ingested isoflavones after ingestion of kinako were recovered on d 2 or 3 in the feces. Total recovery of daidzein, O-DMA and equol from urine and feces was 54.7%, calculated from daidzein intake; 20.1% of administered genistein was recovered as genistein. The half-lives of plasma genistein and daidzein were 8.36 and 5.79 h, respectively. The individual plasma and urinary concentrations of equol and O-DMA were quite variable; subjects were classified as high and low metabolizers. The high plasma concentration of isoflavones for at least several hours after a single ingestion of soy protein suggests that these compounds may interact with macromolecules and have biological effects.
为了利用大豆异黄酮的多种药理活性，需要对这些化合物在人体中的吸收和排泄速率进行更详细的研究，并随后评估它们的生物利用度。我们对7名健康男性志愿者进行了大豆异黄酮的药代动力学研究。摄入60克黄豆粉（烘焙大豆粉，含有103微摩尔大豆苷元和112微摩尔染料木黄酮）后，通过气相色谱-质谱法测量血浆、尿液和粪便中异黄酮及其代谢物浓度的变化。染料木黄酮的血浆浓度在2小时后升高，并在6小时后达到2.44±0.65微摩尔/升的最高值。大豆苷元的血浆浓度在同一时间达到峰值1.56±0.34微摩尔/升，但始终低于染料木黄酮。在4名和2名受试者中，O-去甲基安哥拉紫檀素（O-DMA）和雌马酚的血浆峰值浓度分别出现在大豆苷元峰值之后。与血浆相反，大豆苷元是尿液中的主要成分。摄入黄豆粉后，血浆浓度升高后不久，尿中大豆苷元排泄开始增加，并在摄入后8小时达到2.4微摩尔/小时。尿中染料木黄酮的排泄与大豆苷元平行，但6小时时的值约为一半（1.1微摩尔/小时）。摄入黄豆粉后，大部分摄入的异黄酮在第2天或第3天在粪便中回收。根据大豆苷元摄入量计算，尿和粪便中大豆苷元、O-DMA和雌马酚的总回收率为54.7%；20.1%的给药染料木黄酮以染料木黄酮形式回收。血浆中染料木黄酮和大豆苷元的半衰期分别为8.36小时和5.79小时。个体血浆和尿液中雌马酚和O-DMA的浓度差异很大；受试者被分为高代谢者和低代谢者。单次摄入大豆蛋白后，异黄酮在至少几个小时内血浆浓度较高，这表明这些化合物可能与大分子相互作用并产生生物学效应。
