Chemical compounds of extracts from Sarcodon imbricatus at optimized growth conditions

Abstract

The effect of carbon and nitrogen sources and initial pH and temperature of the medium on the mycelial growth of Sarcodon imbricatus (L.) P. Karst. in axenic liquid culture was investigated. The optimal composition of the medium was found to be: 5% fructose, 1% hydrolysate of casein, 1% yeast extract, and 0.3% KH₂PO₄ at pH = 6 and incubation temperature of 20°C. In this condition the maximum biomass growth was observed, yielding 10.2 g L⁻¹ of dry weight after 3-week of growth. The medium regarded as optimal for growth of S. imbricatus mycelium was used for the production of the biomass and further chemical analysis. The quantitative and qualitative composition of phenolic acids, fatty acids, and sterols were determined using chromatographic methods. The total content of phenolic acids was 1.86 mg × 100 g⁻¹ DW, with the largest amount of protocatechuic acid (1.27 mg × 100 g⁻¹ DW). Nineteen fatty acids were estimated, including five unsaturated fatty acids, e.g., oleic and α-linolenic acid. The analysis of sterols composition revealed the presence of ergosterol and ergosterol peroxide (197.7 and 200.47 mg × 100 g⁻¹ DW, respectively). These compounds were isolated and confirmed by ¹H-NMR. Presented study constitutes the first report on the accumulation of substances (phenolic acids, fatty acids, and sterols) with multidirectional biological activity in the mycelial axenic culture of Sarcodon imbricatus.