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For Podospora anserina, several studies of cellulolytic enzymes have been established, but characteristics of amylolytic enzymes are not well understood. When P. anserina grew in starch as carbon source, it accumulated glucose, nigerose, and maltose in the culture supernatant. At the same time, the fungus secreted α-glucosidase (PAG). PAG was purified from the culture supernatant, and was found to convert soluble starch to nigerose and maltose. The recombinant enzyme with C-terminal His-tag (rPAG) was produced with Pichia pastoris. Most rPAG produced under standard conditions lost its affinity for nickel-chelating resin, but the affinity was improved by the use of a buffered medium (pH 8.0) supplemented with casamino acid and a reduction of the cultivation time. rPAG suffered limited proteolysis at the same site as the original PAG. A site-directed mutagenesis study indicated that proteolysis had no effect on enzyme characteristics. A kinetic study indicated that the PAG possessed significant transglycosylation activity.

Tremella fuciformis Berk (TFB) has long been used as a traditional medicine in Asia. Although TFB exhibits antioxidant and anti-inflammatory effects, the mechanisms of action responsible have remained unknown. We confirmed the anti-inflammatory effects of Tremella fuciformis Berk extract (TFE) in RAW 264.7 cells and observed significantly suppressed LPS-induced iNOS/NO and COX-2/PGE2 production. TFE also suppressed LPS-induced IKK, IkB, and p65 phosphorylation, as well as LPS-induced translocation of p65 from the cytosol. Additionally, TFE inhibited LPS-induced phosphorylation of MAPKs. In an acute inflammation study, oral administration of TFE significantly inhibited LPS-induced IL-1β, IL-6 and TNF-α production and iNOS and COX-2 expression. The major bioactive compounds from TFB extract were identified as gentisic acid, protocatechuic acid, 4-hydroxybenzoic acid, and coumaric acid. Among these compounds, protocatechuic acid showed the strongest inhibitory effects on LPS-induced NO production in RAW 264.7 cells. Overall, these results suggest that TFE is a promising anti-inflammatory agent that suppresses iNOS/NO and COX-2/PGE2 expression, as well as the NF-κB and MAPK signaling pathways.

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