This study aimed to investigate the metabolic fate of bioactive components in watermelon and explore their effect on endothelial function. Six healthy overweight/obese (BMI: 28.7 ± 1.6 kg/m²) adults received 100 kcal of watermelon flesh (WF), rind (WR), seeds (WS), or control meal. l-Citrulline, arginine, and (poly)phenolic metabolites were characterized in plasma over 24 h using UHPLC-MS. Endothelial function was assessed using a flow mediated dilation (FMD) technique over 7 h. Maximum concentration (C_max) and area under the curve (AUC_0–8h) of l-citrulline were significantly higher after WF- and WR-containing test meals compared to control (p < 0.05). Likewise, several individual phenolic metabolites in plasma had significantly higher C_max after WR, WF, or WS intake compared to control. FMD responses were not different among test meals. Our results provide insights on circulating metabolites from watermelon flesh, seed, and rind and lay the foundation for future clinical trials on vascular benefits of watermelon.

中文翻译：

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人体血浆中西瓜（果皮、果肉和种子）生物活性成分的药代动力学参数：一项调查与内皮功能关系的试点研究。

本研究旨在调查西瓜中生物活性成分的代谢归宿，并探讨它们对内皮功能的影响。六名健康的超重/肥胖 (BMI: 28.7 ± 1.6 kg/m ² ) 成年人接受了 100 kcal 的西瓜肉 (WF)、果皮 (WR)、种子 (WS) 或对照膳食。使用 UHPLC-MS 在 24 小时内对血浆中的l-瓜氨酸、精氨酸和（多）酚类代谢物进行表征。使用流量介导的扩张 (FMD) 技术在 7 小时内评估内皮功能。最大浓度（ç_最大值曲线下）和面积（AUC _0-8h）的升含WR-试验餐相比，控制WF-和之后（ -瓜氨酸是显著更高p< 0.05)。同样，与对照相比，在 WR、WF 或 WS 摄入后，血浆中的几种单独的酚类代谢物具有显着更高的C _max。FMD 反应在测试餐之间没有差异。我们的研究结果为西瓜果肉、种子和果皮的循环代谢物提供了见解，并为未来关于西瓜血管益处的临床试验奠定了基础。