Abstract: The effect of cold stress (4 ℃) on metabolites of six strains of the cold resistant yeast Wickerhamomyces anomalus was investigated in this paper. The fermentation broths of these yeast strains was derivatized with methoxamine and BSTFA-TMS, and then the products were determined by gas chromatography-mass spectrometry (GC-MS). A total of 49 metabolites with more than 10 mg/L concentrations were identified, including 34 saccharides, sugar alcohols and sugar acids, several of which had prebiotic activity. These results indicate that the W. anomalus has complex saccharide metabolic ability. In addition, W. anomalus produced squalene, thymol-β-D-glucoside, β-hydroxy-phenylpropionic acid, and isolongifolene, suggesting that this yeast has metabolic pathways of terpenoids and phenylpropanoids. According to the results of metabolome analysis, glycerol, squalene, erythritol, galactose, L-ascorbic acid-2,6-dipalmitate, mannose, and thymol-β-Dglucoside were the bio-markers of W. anomalus under cold stress. This study provides a theoretical basis for the studying the response mechanism of yeast to cold stress and the mechanism underlying flavor formation in yeast-fermented foods, and for the development of new products.

Key words: Wickerhamomyces anomalus, cold stress, gas chromatography-mass spectrometry, metabolome, markers