Identifying the compounds that can distinguish between Saposhnikovia root and its substitute, Peucedanum ledebourielloides root, using LC-HR/MS metabolomics
作者:Taichi Yoshitomi、Daigo Wakana、Nahoko Uchiyama、Takashi Tsujimoto、Noriaki Kawano、Tsuguo Yokokura、Yutaka Yamamoto、Hiroyuki Fuchino、Takashi Hakamatsuka、Katsuko Komatsu、Nobuo Kawahara、Takuro Maruyama
DOI:10.1007/s11418-020-01409-6
日期:2020.6
Previously, we established a 1H NMR metabolomics method using reversed-phase solid-phase extraction column (RP-SPEC), and succeeded in distinguishing wild from cultivated samples of Saposhnikoviae radix (SR), and between SR and its substitute, Peucedanum ledebourielloides root (PR). Herein, we performed LC-HR/MS metabolomics using fractions obtained via RP-SPEC to identify characteristic components of SR and PR. One and three characteristic components were respectively found for SR and PR; these components were isolated with their m/z values and retention times as a guide. The characteristic component of SR was identified as 4′-O-β-d-glucosyl-5-O-methylvisamminol (1), an indicator component used to identify SR in the Japanese Pharmacopoeia. In contrast, the characteristic components of PR were identified as xanthalin (2), 4′-O-β-d-apiosyl (1 → 6)-β-d-glucosyl-5-O-methylvisamminol (3), and 3′-O-β-d-apiosyl (1 → 6)-β-d-glucosylhamaudol (4) based on spectroscopic data such as 1D- and 2D-NMR, MS, and specific optical rotation. Among them, 4 is a novel compound. For the correlation between the NMR metabolomics results in the present and our previous report, only 1 and 2 were found to correlate with the chemical shifts, and the other compounds had no correlation. As the chemical shifts for compounds 1, 3, and 4 were similar to each other, especially for the aglycone moiety, they could not be distinguished because of the sensitivity and resolution of 1H NMR. Accordingly, combining NMR and LC/MS metabolomics with their different advantages is considered useful for metabolomics of natural products. The series of methods used in our reports could aid in quality evaluations of natural products and surveying of marker components.
在此之前,我们利用反相固相萃取柱(RP-SPEC)建立了一种 1H NMR 代谢组学方法,并成功区分了 Saposhnikoviae radix(SR)的野生与栽培样品,以及 SR 与其替代品 Peucedanum ledebourielloides root(PR)之间的区别。在此,我们利用通过 RP-SPEC 获得的馏分进行了 LC-HR/MS 代谢组学分析,以确定 SR 和 PR 的特征成分。在 SR 和 PR 中分别发现了一种和三种特征成分;以这些成分的 m/z 值和保留时间为指导,对其进行了分离。SR 的特征成分被鉴定为 4′-O-β-d-glucosyl-5-O-methylvisamminol (1),这是日本药典中用于鉴定 SR 的指标成分。相比之下,根据 1D- 和 2D-NMR、质谱和比旋光度等光谱数据,PR 的特征成分被鉴定为黄连素(2)、4′-O-β-d-apiosyl (1 → 6)-β-d-glucosyl-5-O-methylvisamminol (3)和 3′-O-β-d-apiosyl (1 → 6)-β-d-glucosylhamaudol (4)。其中,4 是一种新型化合物。关于本报告与之前报告中核磁共振代谢组学结果的相关性,发现只有 1 和 2 与化学位移相关,其他化合物没有相关性。由于化合物 1、3 和 4 的化学位移相似,尤其是苷元的化学位移相似,因此受限于 1H NMR 的灵敏度和分辨率,无法将它们区分开来。因此,将具有不同优势的 NMR 和 LC/MS 代谢组学方法结合起来对天然产物的代谢组学研究非常有用。我们报告中使用的一系列方法有助于天然产品的质量评估和标记成分的调查。