Cho E S, Coon J D, Stegink L D
Food Chem Toxicol. 1987 Jul;25(7):499-504. doi: 10.1016/0278-6915(87)90200-6.
In aqueous solution, aspartame can cyclicize to form its corresponding diketopiperazine (3-carboxymethyl-6-benzyl-2,5-diketopiperazine; DKP) and methanol. We measured plasma and urinary concentrations of DKP in samples obtained from six normal adult subjects ingesting 2.2 mg DKP/kg body weight. The DKP was administered as part of a dose of 200 mg aspartame/kg body weight. DKP concentrations in plasma were below the detection limit (less than 1 microgram/ml) of the high-pressure liquid chromatographic method at each time interval after ingestion at which they were measured. Mean (+/- SD) total urinary DKP excreted during the first 24-hr period after dosing was 6.68 +/- 1.30 mg (4.83 +/- 0.23% of the ingested DKP dose). Approximately 44% of the total DKP excreted was excreted in the first 4 hr after dosing.
在水溶液中，阿斯巴甜可环化形成其相应的二酮哌嗪（3-羧甲基-6-苄基-2,5-二酮哌嗪；DKP）和甲醇。我们测定了从6名摄入2.2毫克DKP/千克体重的正常成年受试者采集的样本中血浆和尿液中DKP的浓度。DKP作为200毫克阿斯巴甜/千克体重剂量的一部分给药。在摄入后各测量时间间隔，血浆中DKP浓度均低于高压液相色谱法的检测限（低于1微克/毫升）。给药后首个24小时期间，平均（±标准差）总尿DKP排泄量为6.68±1.30毫克（占摄入DKP剂量的4.83±0.23%）。排泄的总DKP中约44%在给药后最初4小时内排出。
