Department of Gastrointestinal Microbiology, German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany.
Mol Nutr Food Res. 2010 Oct;54(10):1405-13. doi: 10.1002/mnfr.200900517.
The impact of human intestinal bacteria on the bioavailability of the prenylflavonoid xanthohumol (XN) was studied by comparing germ-free (GF) and human microbiota-associated (HMA) rats. After XN application, XN, XN conjugates, and isoxanthohumol (IX) conjugates occurred in blood samples of GF and HMA rats, whereas IX was detected only in the blood of HMA rats. Overall excretion of XN and its metabolites within 48 h was only 4.6% of the ingested dose in GF rats and 4.2% in HMA rats, feces being the major route of excretion. While both GF and HMA rats excreted XN, IX, and their conjugates with urine and feces, 8-prenylnaringenin and its corresponding conjugates were exclusively observed in the feces of HMA rats. The microbial formation of 8-prenylnaringenin was confirmed by incubation of XN and IX with human fecal slurries. The amount of conjugates excreted in urine and feces was lower in HMA rats compared to GF rats indicating their hydrolysis by human intestinal microbiota. Thus, the impact of bacteria on the XN metabolism in the gut may affect the in vivo effects of ingested XN.
研究了人类肠道细菌对类黄酮化合物黄腐酚（XN）生物利用度的影响，比较了无菌（GF）和人微生物群相关（HMA）大鼠。XN 应用后，GF 和 HMA 大鼠的血液样本中出现了 XN、XN 缀合物和异黄腐酚（IX）缀合物，而 HMA 大鼠的血液中仅检测到 IX。GF 大鼠和 HMA 大鼠在 48 小时内，XN 及其代谢物的总排泄量仅为摄入剂量的 4.6%，粪便为主要排泄途径。GF 和 HMA 大鼠均通过尿液和粪便排泄 XN、IX 和它们的缀合物，但 8-异戊烯基柚皮素及其相应的缀合物仅在 HMA 大鼠的粪便中观察到。XN 和 IX 与人粪便混悬液孵育证实了 8-异戊烯基柚皮素的微生物形成。与 GF 大鼠相比，HMA 大鼠尿液和粪便中排泄的缀合物量较低，表明其被人肠道微生物群水解。因此，细菌对肠道中 XN 代谢的影响可能会影响摄入 XN 的体内作用。
