De Roos B, Meyboom S, Kosmeijer-Schuil T G, Katan M B
Division of Human Nutrition and Epidemiology, Wageningen Agricultural University, Wageningen, The Netherlands.
J Intern Med. 1998 Dec;244(6):451-60. doi: 10.1046/j.1365-2796.1998.00386.x.
To determine the absorption and urinary excretion of the cholesterol-raising coffee diterpenes cafestol and kahweol in humans.
Nine healthy ileostomists consumed a dose of one, two or three cups of French-press coffee together with a standardized breakfast on three separate days in random order. Subsequently, ileostomy effluent was collected for 14 h and urine for 24 h. Stability of cafestol and kahweol was also assessed under simulated gastrointestinal tract conditions.
Absorption of diterpenes, stability of diterpenes during incubation with gastrointestinal fluids, and urinary excretion of diterpenes.
Corrected mean absorptions expressed as percentages of the amount consumed and the amount entering the duodenum were 67 and 88%, respectively, for cafestol, and 72 and 93%, respectively, for kahweol. We found losses of diterpenes during incubation in vitro with gastric juice (cafestol, 24%; kahweol, 32%), during storage with ileostomy effluent (cafestol, 18%; kahweol, 12%), and during freeze-drying (cafestol, 26%; kahweol, 32%). Mean excretion of glucuronidated plus sulphated conjugates in urine was 1.2% of the ingested amount for cafestol and 0.4% of the ingested amount for kahweol.
About 70% of the ingested cafestol and kahweol is absorbed in ileostomy volunteers. Possibly, undetected metabolites are present in ileostomy effluent, resulting in lower absorption percentages. Only a small part of the diterpenes is excreted as a conjugate of glucuronic acid or sulphate in urine. Therefore, these compounds are extensively metabolized in the human body.
测定可升高胆固醇的咖啡二萜成分咖啡豆醇和卡维醇在人体中的吸收及尿排泄情况。
9名健康的回肠造口术患者在3个不同日期按随机顺序，与标准化早餐一起饮用一剂一杯、两杯或三杯法式滤压咖啡。随后，收集14小时的回肠造口流出物和24小时的尿液。还在模拟胃肠道条件下评估了咖啡豆醇和卡维醇的稳定性。
二萜的吸收情况、二萜在与胃肠液孵育过程中的稳定性以及二萜的尿排泄情况。
以摄入剂量和进入十二指肠的量的百分比表示的校正后平均吸收率，咖啡豆醇分别为67%和88%，卡维醇分别为72%和93%。我们发现，二萜在体外与胃液孵育期间（咖啡豆醇，24%；卡维醇，32%）、与回肠造口流出物储存期间（咖啡豆醇，18%；卡维醇，12%）以及冷冻干燥期间（咖啡豆醇，26%；卡维醇，32%）均有损失。尿中葡萄糖醛酸化加硫酸化结合物的平均排泄量，咖啡豆醇为摄入剂量的1.2%，卡维醇为摄入剂量的0.4%。
回肠造口术志愿者中，约70%摄入的咖啡豆醇和卡维醇被吸收。回肠造口流出物中可能存在未检测到的代谢产物，导致吸收百分比降低。只有一小部分二萜以葡萄糖醛酸或硫酸盐结合物的形式经尿液排泄。因此，这些化合物在人体内会被广泛代谢。
