A novel lectin was isolated from the dried fruiting bodies of the wild mushroom Paxillus involutus. Isolation was conducted by anion exchange chromatography on DEAE-Cellulose, Q-Sepharose and gel filtration on Superdex 75 using a fast protein liquid chromatography (FPLC) system. This lectin had a molecular mass of 28 kDa and was composed of four identical subunits, each with a molecular mass of 7 kDa. N-terminal amino acid sequence of the P. involutus lectin was determined to be CTCAVFLNNTTVKS, which showed a low level of similarity to mushroom lectin sequences reported previously. The biochemical properties of this lectin were determined, and the hemagglutinating activity was inhibited by inulin and O-Nitrophenyl-β-D-galacto-pyranoside. Additionally, Ca2+, Zn2+, Cd2+, Fe2+, and Al3+ inhibited its hemagglutinating activity, while Cu2+ promoted this activity. This lectin exhibited poor thermostability and was sensitive to HCl, but it had a high tolerance to NaOH exposure. In terms of biological properties, this lectin manifested antiphytovirus activity towards tobacco mosaic virus (TMV) with a 70.61% inhibition at a concentration of 200 µg/mL. This lectin was devoid of inhibitory activities toward pathogenic fungi and HIV-1 reverse transcriptase, and antiproliferative activities were observed in tumor cell lines including lung cancer A-549 and human colon cancer HCT-8 cells.

The feasibility of solid-state fermentation was studied for sea buckthorn seed residues (SBSR). Effects of different fermentation parameters were evaluated regarding the levels of biomass and compounds in aqueous and non-aqueous extracts. In the latent and logarithmic phases of fermentation, the total phenols and flavonoids were increased. The microbes’ decomposition on fibrous matter allowed the active components to be fully extracted. The changes of total sugar levels had a contrary trend with the changes of total phenol and flavonoid contents. The monosaccharide and polypeptide contents decreased dramatically and then kept steady along with the fermentation. Unsuitable environments led to weak growth of the fungi, limited enzyme contents, low enzyme activity, and a poor degradation of the substrates. The active compounds considered in the study were protected, and the contents reached a maximum under conditions that were usually not suitable for the fungal growth. The chemical structure was another important factor influencing the content and stability of the compounds. The content of procyanidins decreased dramatically because of its sensitivity to heat and alkaline environments. Antioxidant abilities of SBSR extracts, both aqueous and non-aqueous, increased after fermentation. These results reflected a possibility to recycle SBSR for further use in the food industry.