Protective Effects of Exogenous Trehalose on Brewer’s Yeast under Heat Stress

Abstract:

The protective effect of exogenous trehalose on brewer's yeast under heat stress was investigated via measuring the cell viability and vitality under 3 heat stress conditions, and the underlying mechanism was further studied via preliminary transcriptional analysis. As a result, exogenous trehalose was sufficient in improving the heat tolerance of brewer's yeast within the limited period and temperature ranges. The differences in the protective effects of various concentrations of trehaloseshrank with the increase of treatment temperature and duration. Moreover, the addition of exogenous trehalose elevated the intracellular trehalose level. Transcriptional analysis revealed that differentially expressed genes caused by trehaloseaddition mainly centered in ribosome biogenesis and related functions. It was thus speculated that the improved heat tolerance of brewer's yeast after adding exogenous trehalose to the culture medium was achieved by the elevated intracellular trehalose level. The increased level of intracellular trehalose promoted ribosome pathways andstrengthened the ribosome functions, further improving the heat tolerance of brewer's yeast.