Dereplication of Natural Products Using GC-TOF Mass Spectrometry: Improved Metabolite Identification By Spectral Deconvolution Ratio Analysis

Frontiers in Molecular Biosciences

Haiwei Gu¹  Fausto Carnevale Neto²  Norberto Peporine Lopes²  Daniel Raftery³  Rafael Teixeira Freire⁴  Denise Medeiros Selegato⁵  Alan Cesar Pilon⁵  Ian Castro-Gamboa⁵ 

[1] East China Institute of Technology;Faculdade de Ciências Farmacêuticas USP;Fred Hutchinson Cancer Research Center;Instituto de Física de São Carlos (IFSC) USP;Instituto de Quimica UNESP;University of Washington;

关键词: GC-MS;    Ratio analysis;    Compound identification;    peak deconvolution;    plant metabolomics;   

DOI  :  10.3389/fmolb.2016.00059

来源: DOAJ

【 摘 要 】

Dereplication based on hyphenated techniques has been extensively applied in plant metabolomics, avoiding re-isolation of known natural products. However, due to the complex nature of biological samples and their large concentration range, dereplication requires the use of chemometric tools to comprehensively extract information from the acquired data. In this work we developed a reliable GC-MS-based method for the identification of non-targeted plant metabolites by combining the Ratio Analysis of Mass Spectrometry deconvolution tool (RAMSY) with Automated Mass Spectral Deconvolution and Identification Systemsoftware (AMDIS). Plants species from Solanaceae, Chrysobalanaceae and Euphorbiaceae were selected as model systems due to their molecular diversity, ethnopharmacological potential and economical value. The samples were analyzed by GC-MS after methoximation and silylation reactions. Dereplication initiated with the use of a factorial design of experiments to determine the best AMDIS configuration for each sample, considering linear retention indices and mass spectral data. A heuristic factor (CDF, compound detection factor) was developed and applied to the AMDIS results in order to decrease the false-positive rates. Despite the enhancement in deconvolution and peak identification, the empirical AMDIS method was not able to fully deconvolute all GC-peaks, leading to low MF values and/or missing metabolites. RAMSY was applied as a complementary deconvolution method to AMDIS to peaks exhibiting substantial overlap, resulting in recovery of low-intensity co-eluted ions. The results from this combination of optimized AMDIS with RAMSY attested to the ability of this approach as an improved dereplication method for complex biological samples such as plant extracts.

【 授权许可】

Unknown