abstract
- Although guttation is a well-known feature of several filamentous fungi, their potential as natural antioxidant sources is unknown. This study investigates the antioxidant capacity of the exudate produced by the wild edible mushroom Suillus bovinus and the effect of the temperature and of light/darkness exposure on antioxidants synthesis. The fungus was grown on solid media at 18 ◦C or 25 ◦C, under light/darkness conditions. The antioxidant activity of the exudate was evaluated by using 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity (DPPH) and reducing power assays. The fungal exudate proved to have antioxidant activity, showing values of reducing power ranging from 0.450 to 0.528, and of scavenging effects on DPPH radicals from 75.68 to 82.38%. Colonies grown under continuous light at 18 ◦C had the lowest growth rate and exudate volume, but these environmental conditions proved to be the most appropriate to increase antioxidant activity of the droplets. These results indicated that the droplets of S. bovinus are a promising source of natural antioxidants and provide useful information on how to manipulate the production of such compounds.