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In order to explore novel producing strategies for enhancing flavor compounds profile and quality of strawberry wine, we studied the effect of the sequential fermentation of two selected indigenous non-Saccharomycesyeasts (Hanseniaspora uvarumPGR9 and Kurtzmaniella quercitrusaPGT1) and Saccharomyces cerevisiaeCGMCC 2.3854 on the fermentation kinetics, physicochemical characteristics, organic acids, antioxidant activity, volatile compositions, and sensory properties. Results showed that the ethanol content produced by the fermentation of Kq-Scwas significantly lower than that of Scpure fermentation. In addition, the total volatile compounds concentration produced by the fermentation of Hu-Sc(16.2 ± 3.6 mg/L) and Kq-Sc(19.5 ± 3.1 mg/L) were significantly higher than that of Scpure fermentation (13.8 ± 2.0 mg/L). In particular, the Kq-Scstrawberry wine presented the highest number of relative odor-active compounds (rOAV ≥1). Moreover, strawberry wine fermented by Hu+Kq-Scshowed the highest ABTS free radical scavenging ability and the highest overall sensory qualities. The results indicated that the K. quercitrusaPGT1 strain could be an alternative yeast for producing strawberry wine, and the sequential fermentations of Kq-Sc and Hu+Kq-Scwere effective strategies for improving the flavor and quality of strawberry wine.

Ergothioneine (EGT) is a natural sulfur-containing amino acid with potent antioxidant and cytoprotective activities. In this study, the oxidation tolerance of 23 different Rhodotorulastrains were screened with hydrogen peroxide (H2O2) as the inhibitory condition. By measuring their carotenoid and EGT production and correlation analysis with H2O2tolerance, the results showed that the carotenoid synthesis capacity has no effect on H2O2tolerance, in contrast to a strong positive correlation between EGT yield and H2O2tolerance of Rhodotorulaspecies. In addition, a high EGT-producing strain R. mucilaginosaDL-X01 was screened with the yield of 38.48 ± 2.71 mg/L in a shaking flask fermentation. To the best of our knowledge, this is the highest EGT yield ever reported in non-recombinant strains. Growth kinetic data showed that DL-X01 had a longer lag phase in the presence of exogenous oxidant, but a shorter generation time and higher specific growth rate after entering the exponential phase. The results of this study provided a potential simple and rapid method for screening high EGT-producing strains, which could promote the efficient production of EGT by microorganisms and further development of the red yeast in the food and biotechnology industries.