Faculty of Agriculture and Marine Science, Kochi University, Monobe B-200, Nankoku, Kochi, 783-8502, Japan.
Center for Regional Sustainability and Innovation, Kochi University, 2-17-47 Asakura-Honmachi, Kochi, 780-8073, Japan.
Anal Sci. 2020 Aug 10;36(8):977-980. doi: 10.2116/analsci.19P470. Epub 2020 Feb 28.
The cyclic dipeptides, 2,5-diketopiperazines (DKPs), draw attention as bioactive and taste compounds. DKPs, especially those containing Proline (Pro), are contained in heated and fermented foods. Herein, we developed a method for a simultaneous quantitative analysis of Pro-containing DKPs using LC-MS/MS. After optimizing the LC-MS/MS conditions, the developed method was applied to quantify Pro-containing DKPs in Goishi tea, which is a post-fermented tea produced by a two-step aerobic-anaerobic fermentation process. Consequently, 17 kinds of Pro-containing DKPs could be quantified, and the total amount of Pro-containing DKPs was 3.40 mg/L. The recovery in a spiked test was 93 - 117%, which is satisfactory. We believe that the developed method can be used to elucidate the role of Pro-containing DKPs in food.
环状二肽，2,5-二酮哌嗪（DKPs），作为生物活性和味觉化合物受到关注。DKPs，特别是含有脯氨酸（Pro）的 DKP，存在于加热和发酵的食品中。在此，我们开发了一种使用 LC-MS/MS 同时定量分析含 Pro 的 DKP 的方法。在优化 LC-MS/MS 条件后，该方法应用于定量分析两步有氧-厌氧发酵工艺制成的后发酵茶——甘草茶中的含 Pro 的 DKP。结果，可定量分析 17 种含 Pro 的 DKP，其总含量为 3.40mg/L。加标试验的回收率为 93-117%，令人满意。我们相信，所开发的方法可用于阐明含 Pro 的 DKP 在食品中的作用。
