Evaluation of inhibitory effects of some novel phenolic derivatives on the mushroom tyrosinase activity

Although prime compounds in yeast metabolism, vitamins in oenology have remained mostly unexplored for decades. Here, a premier characterization of the vitamers in white grape musts has been drawn. A RP-HPLC method has therefore been developed for their direct analysis in musts, allowing for the determination of 19 different vitamers from 8 water-soluble vitaminic groups, including thiamine forms T, TMP and TPP, with LODs between 0.1 and 45.9 µg.L−1 and LOQs between 0.4 and 137.8 µg.L−1. A resulting characterization of 85 grape musts has been drawn from their vitaminic composition. Plus, the use of neither sulfites nor filtration affects the must vitamin content. The method stands as a useful tool for the later determination of yeast requirements, or impact of winemaking products on vitamins. The method has, overall, proven as practical and sensitive, for rapid identification of vitamins and vitamers in musts.