Influence of Organic and Inorganic Compounds of Various Metals on the Synthesis of Polysaccharides by the Medicinal Mushroom Trametes versicolor.

Background: To date, basidiomycetes are considered to be promising objects of biotechnology, due to a number of biologically active compounds, such as polysaccharides and triterpenes. These compounds have a high therapeutic potential and demonstrate immunomodulatory, antiviral, and antifungal activities.

Objective: The purpose of this study was to study the effect of various concentrations of metal citrates and sulphates on the content of exo- and endopolysaccharides of the fungus Trametes versicolor.

Method: The mycelium was grown by deep cultivation on a semisyntheticglucose-peptone-yeast medium with different contents of zinc, copper, and manganese salts, after which the extraction and measurement of the concentration of polysaccharides were carried out.

Results: The results obtained showed that copper citrate at a concentration of 4 mg/L had the greatest positive effect on biomass yield. The intensity of biomass growth on a nutrient medium with copper citrate increased by 80%. Zinc citrate increased the content of exopolysaccharides by 29% compared to the medium without metal salts. When manganese citrate was added to the medium, the productivity of synthesis decreased, but an increase in the growth rate of mycelium biomass was observed. Sulphates of these metals led to a decrease in the productivity of exopolysaccharide synthesis by 12% for zinc and 35% for manganese.

Conclusions: The addition of both copper citrate and copper sulphate to the medium led to a decrease in the synthesis productivity by 66 and 24%, respectively. The introduction of both citrates and sulphates of these metals into the culture medium led to an increase in the percentage of endopolysaccharides in the mycelium of the fungus.

Highlights: Copper citrate enhances Trametes versicolor biomass by 80%. Zinc citrate increases exopolysaccharide content by 29%. Copper sulphate optimizes endopolysaccharide production.