Melatonin metabolism in yeast cells during alcoholic fermentation

Identifier:  TDX:2960

Handle: https://hdl.handle.net/20.500.11797/TDX2960

Authors:  Morcillo Parra, María de los Ángeles

Abstract:
Melatonin is an indolamine, which is produced by yeast from the aromatic amino acid, tryptophan, during alcoholic fermentation. Here, we study the production of melatonin in synthetic must in different environmental and nutrition conditions by wine yeast species as well as the effect of this bioactive molecule on the fermentation performance. The results showed that the melatonin detection was delayed between intracellular production, which occurred during lag phase, and extracellular secretion, at the exponential or stationary phase. Additionally, melatonin presence improved fermentation performance and survival of non-Saccharomyces yeasts. We also studied melatonin interactions with proteins during fermentation. Consequently, we found that melatonin was bound to glycolytic enzymes and this interaction is related to yeasts with high fermentative capacity. This reinforces the idea of melatonin acting as a signal molecule during alcoholic fermentation. Finally, we optimized a novel fluorescence method, based on a cell line that presents the human melatonin receptor, in fermented samples. We observed that this new method decreased the limit of detection and was a good alternative in comparison with a chromatographic method, although, an extraction was needed for melatonin analysis.