Optimization of detection methods for oxidative stress in Saccharomyces strains

Entity: Universitat Rovira i Virgili (URV)

Confidenciality: No

Education area(s): Begudes Fermentades

Title in different languages: Optimization of detection methods for oxidative stress in Saccharomyces strains

Abstract: Oxidative stress is a change in the balance of the oxidation - reduction processes in the cell, which generates loss of cellular viability. This stress can be induced by numerous oxidants, including plumbagin, menadione sodium bisulfate, hydrogen peroxide and paraquat, which produce the formation of reactive oxygen species, causing disbalance at the cellular level. Melatonin, which is a hormone found in vertebrates, has been described as an antioxidant molecule in plants and vertebrates. The antioxidant role of melatonin on yeast has been recently described, but only against hydrogen peroxide. Thus, a wide study of its antioxidant capacity would need to be done, by using other oxidative stresses. The main objective of our work was the optimization of detection methods for oxidative stress in strains of Saccharomyces with different conditions. To carry out this study, we analyzed different media and concentrations of oxidants on solid-agar plates, as well as different techniques to apply the oxidant on the plate, and measure the inhibition halo caused by those oxidants. Then, we determined the possible protective effect of melatonin against this oxidative stress. Besides, we also analyzed the effect of the oxidants on cell viability using broth media, to compare the response of cells in solid and liquid media, against different oxidant concentrations. Our results showed that the best conditions to do these assays were using YPD medium and applying the oxidant directly in the plate (hole method). Moreover, the concentration of oxidant agent needed to see an effect on yeast growth on agar plate was much higher than the concentration needed in liquid medium. Finally, the antioxidant effect of melatonin was not evidenced in those conditions, due to the lower concentration tested.

Subject: Enologia

Academic year: 2016-2017

Language: Anglès

Work's public defense date: 2017-06-22

Subject areas: Enology

Student: Bosch Crespo, Diana Marelys

Work's codirector: Beltran Casellas, Gemma

Department: Bioquímica i Biotecnologia

TFM credits: 15

Creation date in repository: 2018-01-10

Keywords: Saccharomyces, oxidative stress, melatonin

Title in original language: Optimization of detection methods for oxidative stress in Saccharomyces strains

Project director: Torija Martínez, María Jesús