Protective effects of bioactive compounds against fermentation-associated stresses in Saccharomyces cerevisiae

Identifier:  TDX:3273

Handle: https://hdl.handle.net/20.500.11797/TDX3273

Authors:  Sunyer Figueres, Mercè

Abstract:
Melatonin and hydroxytyrosol are bioactive molecules that play important roles in various biological processes in mammals, mainly relying on their antioxidant properties. Those molecules are synthesized by yeast during alcoholic fermentation, and melatonin has protective effect against oxidative and UV stresses in yeast cells. The aim of the present thesis was to determine if melatonin and hydroxytyrosol play a protective role against fermentation-related stresses in Saccharomyces cerevisiae cells. First, to deepen into the antioxidant mechanisms of melatonin, we analyzed its effect at the transcriptional level. Exogenous melatonin crossed cell membranes and modulated the expression of many genes: in nonstressed cells, it triggered a hypoxic-like response, while in stressed cells, it provoked an antioxidant response. As the compartment with more genes affected was the mitochondrion, we evaluated the effect of melatonin on mitochondria functionality.