Among many sources of natural bioactive substances, mushrooms constitute a huge and almost unexplored group. Fungal compounds have been repeatedly reported to exert biological effects which have prompted their use in pharmaceutical and cosmetic industry. Therefore, the aim of this study was analysis of chemical composition and biological activity of 31 wild growing mushroom species (including saprophytic and parasitic) from Poland. Qualitative and quantitative LC-ESI-MS/MS analysis of fourteen phenolic acids in the mushrooms analysed was performed. Moreover, total phenolic content was determined by the modified Folin-Ciocalteau method. Antioxidative activity of ethanolic extracts towards DPPH^• free radical was examined. Antibacterial activity against Gram-positive (S. epidermidis, S. aureus, B. subtilis, M. luteus) and Gram-negative (E. coli, K. pneumoniae, P. aeruginosa, P. mirabilis) microbial strains was analyzed. As a result, the first such broad report on polyphenolic composition, antiradical and antimicrobial potential of wild growing Polish mushrooms was developed. Mushroom extracts were found to contain both benzoic (protocatechuic, 4-OH-benzoic, vanillic, syringic) and cinnamic acid derivatives (caffeic, p-coumaric, ferulic). Total phenolic content in mushrooms ranged between 2.79 and 53.13 mg gallic acid equivalent /g of dried extract in Trichaptum fuscoviolaceum and Fomes fomentarius, respectively. Fungi showed much differentiated antiradical activity, from highly active F. fomentarius to poorly effective Russula fragilis (IC₅₀ 1.39 to 120.54 mg per mg DPPH^•, respectively). A quite considerable relationship between phenolic content and antiradical activity has been demonstrated. Mushrooms varied widely in antimicrobial potential (MIC from 0.156 to 5 mg/ml). Generally, a slightly higher activity against Gram-positive than Gram-negative strains was observed. This is the first study concerning the chemical composition and biological activity of the majority of investigated species.

Purpose According to the vast body of evidence demonstrating that the intestinal microbiota is undoubtedly linked with overall health, including cancer risk, searching for functional foods and novel prebiotic influencing on beneficial bacteria is necessary. The present study aimed to investigate the potential of polysaccharides from 53 wild-growing mushrooms to stimulate the growth of Lactobacillus acidophilus and Lactobacillus rhamnosus and to determine the digestibility of polysaccharide fractions. Methods Mushroom polysaccharides were precipitated with ethanol from aqueous extracts. Determination of growth promoting activity of polysaccharides was performed in U-shaped 96-plates in an ELISA reader in relation to the reference strain of L. acidophilus and two clinical strains of L. rhamnosus. The digestibility of mushroom polysaccharides was investigated in vitro by exposing them to artificial human gastric juice. Results Obtained results revealed that fungal polysaccharides stimulate the growth of Lactobacillus strains stronger than commercially available prebiotics like inulin or fructooligosaccharides. Moreover, selected polysaccharides were subjected to artificial human gastric juice and remain undigested in more than 90%. Conclusion Obtained results indicate that mushroom polysaccharides are able to pass through the stomach unchanged, reaching the colon and stimulating the growth of beneficial bacteria. Majority of 53 polysaccharide fractions were analysed for the first time in our study. Overall, our findings suggest that polysaccharide fractions from edible mushrooms might be useful in producing functional foods and nutraceuticals.

Yarrowia lipolytica, an oleagineous species of yeast, is a carrier of various important nutrients. The biomass of this yeast is an extensive source of protein, exogenous amino acids, bioavailable essenctial trace minerals, and lipid compounds as mainly unsaturated fatty acids. The biomass also contains B vitamins, including vitamin B12, and many other bioactive components. Therefore, Y. lipolytica biomass can be used in food supplements for humans as safe and nutritional additives for maintaining the homeostasis of the organism, including for vegans and vegetarians, athletes, people after recovery, and people at risk of B vitamin deficiencies.