Department of Food Chemistry, Institute of Nutritional Science, University of Potsdam, Arthur-Scheunert-Allee 114-116, D-14558 Nuthetal, Germany.
Br J Nutr. 2010 Jun;103(11):1569-72. doi: 10.1017/S0007114509993564. Epub 2010 Jan 13.
In addition to soya-derived preparations, red clover-based dietary supplements have gained considerable interest as an alternative isoflavone (IF) source. While metabolism and bioavailability of the main IF from both sources have already been investigated, studies are still lacking on the biokinetic behaviour of IF, which are present in red clover in minor amounts. In the present pilot study, in which seven volunteers ingested a single dose of a commercial red clover dietary supplement, we focused on the absorption of three such IF, irilone (IRI), prunetin (PRUN) and pseudobaptigenin (PBAP). The compounds were measured as aglycones after enzymatic hydrolysis. A single intake of an amount of as low as 3.8 mg IRI (out of 38.8 mg IF in total) resulted in an IRI plasma concentration of 0.35 (sd 0.16) mum at 6.5 h post-ingestion. Compared to the plasma concentrations found for daidzein (0.39 mum) and genistein (0.06 mum), expected to be the main IF metabolites in plasma, the present findings indicate that IRI might possess a relatively high bioavailability. Furthermore, PRUN and PBAP were detected in human plasma for the first time.
除了大豆衍生制剂外，基于红车轴草的膳食补充剂作为另一种异黄酮（IF）来源也引起了相当大的关注。虽然这两种来源的主要 IF 的代谢和生物利用度已经得到了研究，但关于红车轴草中含量较少的 IF 的生物动力学行为的研究仍然缺乏。在本初步研究中，七名志愿者摄入了一次剂量的商业红车轴草膳食补充剂，我们专注于三种此类 IF（伊尔酮（IRI）、樱黄素（PRUN）和伪原花青素（PBAP）的吸收。这些化合物在酶解后被测量为糖苷配基。单次摄入低至 3.8 毫克 IRI（总 IF 为 38.8 毫克），在摄入后 6.5 小时，IRI 血浆浓度达到 0.35（标准差 0.16）毫微克/毫升。与预期为血浆中主要 IF 代谢物的大豆苷元和染料木黄酮（0.06 毫微克/毫升）的血浆浓度相比，目前的发现表明 IRI 可能具有相对较高的生物利用度。此外，PRUN 和 PBAP 首次在人血浆中被检测到。
