Effects of maturity stage on the antioxidant components levels and antioxidant properties of three edible mushrooms Russula spp from Côte d'Ivoire

Abstract

This study aimed to assess the antioxidant capacities of three species of edible ectomycorrhizal mushrooms of the genus Russula from Côte d'Ivoire as a function of their maturity stage through changes in the contents of the antioxidant components and properties of their extracts. The contents of total phenolic compounds, flavonoids, tannins and carotenoids were assessed by colorimetric assays whereas ascorbic acid content was estimated by titration. Individual phenolic compounds were analyzed by HPLC for their identification. Three biochemical assays (DPPH scavenging, ABTS scavenging and Ferric reducing antioxidant power) were used to estimate the antioxidant properties. The highest amounts of all the antioxidant components and the majority of individual phenolic compounds analyzed were obtained at the mature stages in the extracts of the three mushrooms. The maximum contents of total phenolic compounds were also obtained in the mature fruiting bodies and were respectively 729.16±0.32, 623.11±0.04 and 832.78±0.01 mg/100g dry matter for Russula lepida, R. mustelina and R. delica. These results were confirmed by the values of the effective concentrations EC₅₀, the lowest of which were obtained at the mature stages and were respectively 0.11±0.03, 0.19±0.09 and 0.09±0.01 mg/ml in terms of DPPH scavenging for R. lepida, R. mustelina and R. delica. This suggests that in terms of the need for natural antioxidants, the mature stage is the appropriate stage for harvesting these mushrooms.