Phellinus linteus mycelia extract in COVID-19 prevention and identification of its key metabolic compounds profiling using UPLC-QTOF-MS/MS spectrometry.

For centuries, food, herbal medicines, and natural products have been valuable resources for discovering novel antiviral drugs, uncovering new structure-activity relationships, and developing effective strategies to prevent/treat viral infections. One such resource is Phellinus linteus, a mushroom used in folk medicine in Taiwan, Japan, Korea, and China. In this rich historical context, the key metabolites of Phellinus linteus mycelia ethanolic extract (GKPL) impacting the entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at multiple stages have yet to be explored. Thus, this study systematically identifies and assesses the inhibitory effect of GKPL on the SARS-CoV-2 virus. Initially, the concentrations and contact times of GKPL against SARS-CoV-2 pseudovirus were assessed in HepG2 cells. Subsequently, utilizing the Ultra Performance Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry method, potential biomarkers in the fungal extract were discerned. Metabolomic analysis identified 18 compounds in GKPL, with hispidin and hypholomine B present in the highest amounts. These compounds were isolated using chromatographic techniques and further identified through 1D NMR spectroscopic and mass spectrometry analysis. Hispidin and hypholomine B were found to inhibit the infection of SARS-CoV-2 pseudovirus by reducing angiotensin-converting enzyme 2 gene expression in HepG2, thereby decreasing viral entry. Moreover, hispidin and hypholomine B effectively block the spike receptor-binding domain, while hypholomine B, for the first time, showed significant inhibition of 3CL protease. This suggests that GKPL, enriched with hispidin and hypholomine B, has the potential to be used as an active ingredient against SARS-CoV-2.

Styrylpyrones from Phellinus linteus Mycelia Alleviate Non-Alcoholic Fatty Liver by Modulating Lipid and Glucose Metabolic Homeostasis in High-Fat and High-Fructose Diet-Fed Mice.

Phellinus linteus (PL), an edible and medicinal mushroom containing a diversity of styrylpyrone-type polyphenols, has been shown to have a broad spectrum of bioactivities. In this study, the submerged liquid culture in a 1600-L working volume of fermentor was used for the large-scale production of PL mycelia. Whether PL mycelia extract is effective against nonalcoholic fatty liver disease (NAFLD) is still unclear. In the high fat/high fructose diet (HFD)-induced NAFLD C57BL/6 mice study, the dietary supplementation of ethyl acetate fraction from PL mycelia (PL-EA) for four weeks significantly attenuated an increase in body weight, hepatic lipid accumulation and fasting glucose levels. Mechanistically, PL-EA markedly upregulated the pgc-1α, sirt1 genes and adiponectin, downregulated gck and srebp-1c; upregulated proteins PPARγ, pAMPK, and PGC-1α, and downregulated SREBP-1 and NF-κB in the liver of HFD-fed mice. Furthermore, the major purified compounds of hispidin and hypholomine B in PL-EA significantly reduced the level of oleic and palmitic acids (O/P)-induced lipid accumulation through the inhibition of up-regulated lipogenesis and the energy-metabolism related genes, ampk and pgc-1α, in the HepG2 cells. Consequently, these findings suggest that the application of PL-EA is deserving of further investigation for treating NAFLD.

Neuraminidase Inhibitors from the Culture Broth of Phellinus linteus.

During the search for neuraminidase inhibitors from medicinal fungi, we found that the culture broth of Phellinus linteus exhibited potent inhibitory activity. Solvent partition, Sephadex LH-20 column chromatography, and high-performance liquid chromatography (HPLC) were performed for purification of two active substances from the culture broth. According to (1)H NMR measurements and comparison of HPLC retention times with those of authentic compounds, their chemical structures were identified as hispidin and hypholomine B. Compounds (hispidin) 1 and 2 (hypholomine B) inhibited neuraminidase, with IC(50) values of 13.1 and 0.03 µM, respectively.

Neuraminidase Inhibitors from the Culture Broth of Phellinus linteus

During the search for neuraminidase inhibitors from medicinal fungi, we found that the culture broth of Phellinus linteus exhibited potent inhibitory activity. Solvent partition, Sephadex LH-20 column chromatography, and high-performance liquid chromatography (HPLC) were performed for purification of two active substances from the culture broth. According to 1H NMR measurements and comparison of HPLC retention times with those of authentic compounds, their chemical structures were identified as hispidin and hypholomine B. Compounds (hispidin) 1 and 2 (hypholomine B) inhibited neuraminidase, with IC50 values of 13.1 and 0.03 microM, respectively.