Study On The Metabolites Of Allium Macrostemon Bunge Using NMR-Based Metabonomics

The main advantage of nuclear magnetic resonance (NMR)-based metabolomics is to analyze the whole metabolites of plant qualitatively and quantitatively and it has many applications in plant science. Plant metabolomics can be used to differentiate plants from different origin, part or after different treatments, which increase our knowledge of how complex metabolic networks interact and how they are dynamically modified under stress adaptation and tolerance processes. Therefore, plant metabolimcs is a helpful technique on phytomedicine studies. This paper focused on the metabolic change of Allium macrostemon Bunge (AMB) in different drying process and different solvent extraction by using NMR and multivariate data analysis, which provides useful information on AMB processing and storage.Phytomedicines are dried mostly in different ways before the process and use, which might arouse some metabolic changes and even lead to some differential on the effect of the medicine. We investigated the metabolic consequences of AMB extracts caused by different drying methods including freeze-drying, shade-drying and sun-drying.31metabolites were found in AMB extracts, among which2compounds hadn’t been assigned yet. There was one metabolite observed in this study, for the first time, uridine. Multivariate statistical analysis showed that different drying methods did give rise to metabolites variation. As a plant osmoprotectant, proline had higher content in three drying extracts compared to fresh extract. As the plant regulating agents, sugars and amino acids changed differently in each drying extracts. Membrane degradation, putrescine formation, tricarboxylic acid cycle, gluconeogenesis and metabolisms mediated by shikimate were also influenced by drying processes. The result indicated that the freeze-drying might be the appropriate drying method for AMB, as the higher content of N-trans-feruloyltyramine, which was a potential effective component in AMB.Extraction is another important aspect during traditional Chinese medicine processing. As solvent property varies, one can get different composed extraction from plant drug by using different kinds of extractant. We studied the metabolonmic difference of AMB extract by various extraction solvents.43metabolites were found in AMB extract, including4unknown compounds. The multivariate data analysis result showed that the composition of metabolites in methanol and water were very similar and the dominant metabolites such as sugars, amino acids and carboxylic acids were in these two extracts. The sulfides distributed in n-butanol extract mostly, together with cysteine, heptadecanoic acid, uridine and adenosine. For ethyl acetate extract, it contained mainly lipid, N-trans-feruloyltyramine and N-(p-coumaroyl) tyramine. It was reported that the sulfides might help to reduce blood lipids, especially methylallyl trisulfide (MATS). Adenosine, N-trans-feruloyltyramine and N-(p-coumaroyl) tyramine were potential effective components in inhibiting platelet aggregation. Our result indicated that n-butanol extract had the highest content for sulfides and adenosine, and ethyl acetate extract for N-trans-feruloyltyramine and N-(p-coumaroyl) tyramine, which suggested that n-butanol and ethyl acetate might be the appropriate solvents for AMB extraction.