Chemical and functional characterization of Leccinum scabrum and Leccinum versipelle

Wild edible mushrooms are widely appreciated in gastronomy, medicine and, pharmacology. In spite of the substantial amount of studies on mushrooms, which have recently received considerable attention, many species are not investigated yet. Among these, Leccinum scabrum (Bull.) Gray and Leccinum versipelle (Fr.) Snell The purpose of the study was to examine the culinary medicinal mushrooms Leccinum scabrum and Leccinum versipelle collected in the wild, , during summer in the subcontinental oak-hornbeam forest belonging to the plant association Tilia cordata – Carpinetum betuli Tracz. 1962 of the Białowieża Forest in Podlaskie Voivodeship situated on the border between Poland and Belarus, as potential sources of proteins and antioxidants and to compare them to other mushrooms species such as the cultivated Hericium erinaceus (Bull.) Pers. and Agaricus bisporus (J.E. Lange) Imbach. This survey concerned, primarily, the study of the best extraction method for polyphenols and proteins, then the application of quantitative, qualitative and, functional analysis of the extracts obtained. First of all, an ultrasound-based extraction (UAE) method was applied to the samples and a microwave assisted extraction method (MAE) was developed and optimised to obtain a higher yield of polyphenols with a lower amount of solvents and sample. Eventually, extraction with acid, base hydrolysis and their combination in different sequences was applied to the mushrooms to release and determine bound phenolics (BPs)an. Once obtained the mushroom’s extracts, the contents, compositions and antioxidant capacities were investigated and determined by the Total Phenolic Content (TPC) and the Total Antioxidant Status Assay (TAS) methods. Furthermore, the identification and the quantification of individual polyphenolic compounds in these extracts were carried out by a validated high-performance liquid chromatography coupled with diode array detection and a triple quadrupole tandem mass spectrometry (HPLC-DAD-ESI-QqQMS/ MS) method. The LC-MS analysis was carried out with 30 phenolic compounds as standards, among which many structures of polyphenols were identified in the sample injection and other compounds were attributed to the main polyphenols subclass. The obtained phenolic profiles revealed the richness in phenolic acids and hydrophylic phenolic compounds of Leccinum scabrum and Leccinum versipelle. These results place these wild mushrooms species among food products with considerable proteins and antioxidants content, when compared to cultivated Hericium erinaceus and Agaricus bisporus.