Chromatographic techniques to assess the profile of biomolecules in different mycorrhizal mushroom species

The consumption of wild mushrooms has been preferred compared to cultivated species in many countries, comprising a large number of species with excellent nutritional properties [1]. Moreover, many species have been reported as having bioactive properties, since they are rich in different biomolecules [2,3]. In the present work seven different wild mushrooms were chemically characterized by chromatographic techniques by using different detectors, in order to evaluate the presence of nutritional and/or bioactive molecules. The studied species were: Amanita caesarea (Scop.) Pers., Cortinarius violaceus (L.) Gray, Lactarius volemus (Fr.) Fr., Leccinum molle (Bon) Bon, Leccinum vulpinum Watling, Suillus granulatus (L.) Roussel and Suillus luteus (L.) Roussel. Some hydrophilic compounds, namely free sugars, were identified by HPLC-RI, and phenolic acids were assessed by HPLC-PDA. Regarding lipophilic compounds, fatty acids were determined by GC-FID and tocopherols by HPLC-fluorescence detection. Mannitol and trehalose were the main free sugars detected. Gallic, protocatechuic and p-hydroxybenzoic acids were the main phenolic acids identified, as well as the related compound cinnamic acid. Monoand polyunsaturated fatty acids were the prevailing fatty acids and generally, β-, γ- and δ-tocopherol were the vitamers of vitamin E detected in the samples. Since these species proved to be a source of biologically active compounds, the antioxidant properties were also evaluated. The antioxidant activity was measured through the reducing power, free radical’s scavenging activity and lipid peroxidation inhibition of their methanolic extracts. All the species revealed antioxidant properties, being S. granulatus and L. vulpinum the most active species. Given the results obtained, other bioactivity assays are planned including the elucidation of the mechanisms of action involved.FCT and FEDER under the PT2020 program for financial support to CIMO (UID/AGR/00690/2013), for F.S. Reis grant (SFRH/BD/111753/2015) and for L. Barros contract.