Biochemical effects of sodium benzoate, potassium sorbate and sodium nitrite on food spoilage yeast Saccharomyces cerevisiae

Food preservatives especially used to prevent microbiological spoilage in nutritional products are among the most indispensable additives. Here, the biochemical effects of three commonly used preservatives, sodium benzoate (SB), potassium sorbate (PS) and sodium nitrite (SN), on Saccharomyces cerevisiae were investigated. 5-100 mM SB, 300 ppm PS and 25-100 mM SN significantly inhibited early exponential yeast cell proliferation compared to the control after 12 h exposure. Cell metabolic activity percentages were also significantly inhibited at the studied highest three concentrations. While glutathione S-transferase activity generally increased after SB and PS treatments, superoxide dismutase activity increased only after 50 mM SB treatment. Although the lipid peroxidation marker malondialdehyde levels generally increased as a result of treatments with food additives, significant increases were determined in 300 ppm PS, and 50 and 100 mM SN groups. According to the principal component and hierarchical cluster analysis, food additive treated groups clearly discriminated from control. Finally, the principal component analysis (PCA) loading plots showed that higher doses of food additives altered lipid concentration, disrupted proteins and increased the concentrations of mannans and beta-glucans. These findings are significant in terms of better understanding the underlying mechanism of food additive induced toxicity for the control of yeast cell proliferation.