Development of metabolome analysis method targeting alkaloids

April 23, 2020

Hope for efficient discovery of medicinal resources

The group of researchers from the RIKEN Center for Sustainable Resources Science and Hoshi University developed a metabolome analysis method targeting indole alkaloids, an important medicinal resource. The method was used in experiments using Catharanthus roseus, a medicinal plant, to make successful achievement in analyses of monoterpene indole alkaloids (MIAs) (identification of composition and structure, as well as visualization of accumulation and distribution).

Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), the group measured the metabolites) of C. roseus grown with a liquid fertilizer labeled with15N, a stable isotope of nitrogen, and C. roseus grown under normal conditions. Using the data obtained, 45 MIAs were specified by: (1) identifying nitrogen-containing metabolites with principal component analysis; (2) verifying the ion derived from the indole skeleton (m/z144.08) and its 15N-labeled ion; (3) determining the number of nitrogen in the molecules; and (4) determining molecular formulas. By performing network analysis using the MS/MS spectrum, the group successfully identified an alkaloid "antirhine," which had not been identified in C. roseus before.

The achievement of the study is expected to contribute to the efficient discovery of indole alkaloids for drug development.

Original article
Analytical Chemistry doi:10.1021/acs.analchem.9b03860
R. Nakabayashi, T. Mori, N. Takeda, K. Toyooka, H. Sudo, H. Tsugawa, K. Saito,
"Metabolomics with 15N labeling for characterizing missing monoterpene indole alkaloids in plants".
Ryo Nakabayashi; Research Scientist
Kazuki Saito; Group Director
Metabolomics Research Group