Abstract:

To clarify the metabolites and their relative contents in rhizome and bulbil of wild Chinese Yam (Dioscorea polystachya Turcz.) from Wuxue, widely targeted LC-MS/MS was used to determine the metabolite profiles in rhizome flesh, rhizome peel, and bulbil of wild Chinese yam from Wuxue, Hubei Province. Differentially accumulated metabolites between bulbil and rhizome flesh and between rhizome peel and rhizome flesh were identified by multivariate and univariate analyses. The result showed that a total of 385 metabolites were detected in rhizome and bulbil of wild Chinese yam from Wuxue. There were 70 differentially accumulated metabolites between bulbil and rhizome flesh, among which 43 metabolites were more significantly accumulated in bulbil, while 27 metabolites had higher accumulation in rhizome flesh. Moreover, a total of 81 differentially accumulated metabolites were identified between rhizome peel and rhizome flesh, including 46 metabolites with higher accumulation in rhizome peel and 35 metabolites with higher accumulation in rhizome flesh. In addition, the rhizome flesh of wild Chinese yam was enriched in amino acids such as valine, methionine and alanine. Compared with rhizome flesh, bulbil had higher levels of 18 flavonoid metabolites such as isohemiphloin, C-hexosyl-chrysoeriol 5-O-hexoside and avicularin, while the rhizome peel was more enriched in trans-zeatin-O-glucoside riboside, acetyl-L-carnitine, vitamin B₂, C-hexosyl-chrysoeriol 7-O-hexoside and quercetin-3-methyl ether. This study demonstrated that rhizome and bulbil of wild Chinese yam from Wuxue contain abundant metabolites, and could be rationally developed and utilized based on the type and function of metabolites.

Key words: Chinese yam, bulbil, widely targeted metabolomics, differentially accumulated metabolites