Antioxidant protective effects of mushroom metabolites

Metabolomic Profiling of Floccularia luteovirens from Different Geographical Regions Proposes a Novel Perspective on Their Antioxidative Activities

Floccularia luteovirens, an endemic resource of the Tibetan Plateau, possesses significant medicinal and ecological values. However, the understanding of antioxidant capacity and metabolic profiling of F. luteovirens from diverse regions remains elusive due to limited resources. Therefore, to comprehensively comprehend the antioxidant capacity and metabolite diversity of F. luteovirens, we conducted a rounded analysis of its antioxidant capacity from three distinct regions using both untargeted and targeted metabolomics. Determination of antioxidant indices, such as ferric ion-reducing antioxidant power (FRAP), total phenolic content (TPC), and flavonoid content (FC), revealed the robust antioxidant capacity of F. luteovirens. QL F. luteovirens (QLFL) exhibited no significant difference compared to ZD F. luteovirens (ZDFL); however, both were significantly distinct from XH F. luteovirens (XHFL) across multiple indices. Furthermore, a positive correlation was observed between FRAP and flavonoid content. A total of 5782 metabolites were identified and chemically classified. Metabolites of F. luteovirens varied significantly at different regions and eight key differential metabolites were screened. Phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, and cyanoamino acid metabolism were the main different regulatory pathways. Consequently, the disparities in the antioxidant activity of F. luteovirens may primarily be ascribed to the biosynthesis and metabolism of phenylalanine, while vanillic acid could potentially serve as a pivotal metabolite influencing the antioxidative capacity of F. luteovirens by targeted metabolomics. These findings enhance our understanding of the composition of F. luteovirens and provide valuable resources for its comprehensive utilization and targeted development.

Effect of Pleurotus eryngii mycelial fermentation on the composition and antioxidant properties of tartary buckwheat

In this study, we investigated the effect of solid-state fermentation of Pleurotus eryngii on the composition and antioxidant activity of Tartary buckwheat (TB). Firstly, the solid-state fermentation of P. eryngii mycelium with buckwheat was carried out, and the fermentation process was explored. The results of the extraction process and method selection experiments showed that the percolation extraction method was superior to the other two methods. The results of extraction rate, active components and antioxidant activity measurements before and after fermentation of TB extract showed that the extraction rate increased about 1.7 times after fermentation. Total flavonoids, rutin and triterpene contents were increased after fermentation compared to control. Meanwhile, LC-MS results showed an increase in the content of the most important substances in the fermented TB extract and the incorporation of new components, such as oleanolic acid, ursolic acid, amino acids, and D-chiral inositol. The fermented TB extract showed stronger antioxidant activity, while the protein and amino acid contents increased by 1.93-fold and 1.94-fold, respectively. This research was the first to use P. eryngii to ferment TB and prepared a lyophilized powder that could be used directly using vacuum freeze-drying technology. Not only the use of solid-state fermentation technology advantages of edible fungi to achieve value-added buckwheat, but also to broaden the scope of TB applications. This study will provide ideas and directions for the development and application of edible mushroom fermentation technology and TB.

Compounds purified from edible fungi fight against chronic inflammation through oxidative stress regulation

Chronic inflammation is associated with various chronic diseases, including cardiovascular disease, neurodegenerative disease, and cancer, which severely affect the health and quality of life of people. Oxidative stress induced by unbalanced production and elimination of reactive oxygen species (ROS) is one of the essential risk factors for chronic inflammation. Recent studies, including the studies of mushrooms, which have received considerable attention, report that the antioxidant effects of natural compounds have more advantages than synthetic antioxidants. Mushrooms have been consumed by humans as precious nourishment for 3,000 years, and so far, more than 350 types have been identified in China. Mushrooms are rich in polysaccharides, peptides, polyphenols, alkaloids, and terpenoids and are associated with several healthy biological functions, especially antioxidant properties. As such, the extracts purified from mushrooms could activate the expression of antioxidant enzymes through the Keap1/Nrf2/ARE pathway to neutralize excessive ROS and inhibit ROS-induced chronic inflammation through the NF-κB pathway. Recently, the antioxidant properties of mushrooms have been successfully applied to treating cardiovascular disease (CAD), neurodegenerative diseases, diabetes mellitus, and cancer. The present review summarizes the antioxidant properties and the mechanism of compounds purified from mushrooms, emphasizing the oxidative stress regulation of mushrooms to fight against chronic inflammation.

Higher Mushroom Consumption Is Associated with Lower Risk of Cancer: A Systematic Review and Meta-Analysis of Observational Studies

Mushrooms are rich in bioactive compounds. The potential health benefits associated with mushroom intake have gained recent research attention. We thus conducted a systematic review and meta-analysis to assess the association between mushroom intake and risk of cancer at any site. We searched MEDLINE, Web of Science, and Cochrane Library to identify relevant studies on mushroom intake and cancer published from 1 January, 1966, up to 31 October, 2020. Observational studies (n = 17) with RRs, HRs, or ORs and 95% CIs of cancer risk for ≥2 categories of mushroom intake were eligible for the present study. Random-effects meta-analyses were conducted. Higher mushroom consumption was associated with lower risk of total cancer (pooled RR for the highest compared with the lowest consumption groups: 0.66; 95% CI: 0.55, 0.78; n = 17). Higher mushroom consumption was also associated with lower risk of breast cancer (pooled RR for the highest compared with the lowest consumption groups: 0.65; 95% CI: 0.52, 0.81; n = 10) and nonbreast cancer (pooled RR for the highest compared with the lowest consumption groups: 0.80; 95% CI: 0.66, 0.97; n = 13). When site-specific cancers were examined, a significant association with mushroom consumption was only observed with breast cancer; this could be due to the small number of studies that were conducted with other cancers. There was evidence of a significant nonlinear dose-response association between mushroom consumption and the risk of total cancer (P-nonlinearity = 0.001; n = 7). Limitations included the potential for recall and selection bias in case-control designs, which comprised 11 out of the 17 studies included in this meta-analysis, and the large variation in the adjustment factors used in the final models from each study. The association between higher mushroom consumption and lower risk of cancer, particularly breast cancer, may indicate a potential protective role for mushrooms in the diet.

Antioxidant Extracts of Three Russula Genus Species Express Diverse Biological Activity

This study explored the biological properties of three wild growing Russula species (R. integra, R. rosea, R. nigricans) from Serbia. Compositional features and antioxidant, antibacterial, antibiofilm, and cytotoxic activities were analyzed. The studied mushroom species were identified as being rich sources of carbohydrates and of low caloric value. Mannitol was the most abundant free sugar and quinic and malic acids the major organic acids detected. The four tocopherol isoforms were found, and polyunsaturated fatty acids were the predominant fat constituents. Regarding phenolic compounds, P-hydroxybenzoic and cinnamic acids were identified in the prepared methanolic and ethanolic extracts, which displayed antioxidant activity through the inhibition of thiobarbituric acid reactive substances (TBARS) formation and oxidative hemolysis; the highest activity was attributed to the R. nigricans ethanolic extract. This is the first report on the antibacterial and antibiofilm potential of the studied species, with the most promising activity observed towards Streptococcus spp. (0.20-0.78 mg/mL as the minimal inhibitory concentration, MIC). The most promising cytotoxic effect was caused by the R. integra methanolic extract on non-small cell lung cancer cells (NCI-H460). Therefore, due to the observed in vitro bioactive properties, the studied mushrooms arise as a source of functional ingredients with potential to be used in novel nutraceutical and drug formulations, which can be used in the treatment of various diseases and health conditions.

Antioxidative, antifungal, cytotoxic and antineurodegenerative activity of selected Trametes species from Serbia

In a last few decades mushrooms are increasingly attracting attention as functional food and sources of biologically active compounds. Several Trametes species have been used for centuries in traditional medicine of East Asia cultures, but only T. versicolor was studied sufficiently while there are less substantial data about medicinal properties of other species. Trametes versicolor, T. hirsuta and T. gibbosa were the species tested for biological activities. Antifungal potentials of extracts were assessed for clinical strains of selected Candida and Aspergillus species. ABTS and FRAP assays were used to evaluate antioxidant capacities of studied extracts. Cytotoxic activity was determined against human cervix and lung adenocarcinoma and colon carcinoma cell lines. Antineurodegenerative activity was assessed by determining the rate of acetylcholinesterase and tyrosinase activity. The presence of metabolites in extracts of mycelia and basidiocarps of studied Trametes species was analyzed by 1H NMR spectroscopy. Studied extracts showed low antifungal potential in comparison with ketoconazole. Basidiocarp extracts were more effective ABTS+ scavengers and Fe2+ reducers than mycelium ones but less effective in comparison with L-ascorbic acid. Results showed that mycelium extracts had stronger cytotoxic effects against three cancer cell lines than basidiocarp ones, and that cervix adenocarcinoma cells were the most sensitive to the extracts and commercial cytostatics. T. versicolor mycelium extract was the most effective inhibitor of acetylcholinesterase activity but double weaker than galantamine, and T. gibbosa mycelium extract was significantly better inhibitor of tyrosinase activity than kojic acid for 40.9%. Chemical analysis indicated strong synergistic action of triterpenes, sugars and polyphenols in applied assays. The results suggest that tested Trametes species have significant medicinal potentials which could be attributed to antioxidative and cytotoxic activity. Additionally both, basidiocarps and mycelia extracts can strongly inhibit activity of acetylcholinesterase and tyrosinase.

Alpha-terpineol affects synthesis and antitumor activity of triterpenoids fromAntrodia cinnamomeamycelia in solid-state culture

To enhance production ofAntrodia cinnamomeatriterpenoids (ACTs) from mycelia in solid-state culture, α-terpineol was added to the medium as an elicitor at an optimal concentration of 0.05 mL L⁻¹.

In Vitro Antioxidant Activities and in Vivo Anti-Hypoxic Activity of the Edible Mushroom Agaricus bisporus (Lange) Sing. Chaidam

With the rising awareness of a healthy lifestyle, natural functional foods have gained much interest as promising alternatives to synthetic functional drugs. Recently, wild Agaricus bisporus (Lange) Sing. Chaidam has been found and artificially cultivated for its thick fresh body and excellent taste, with its antioxidant and anti-hypoxic abilities unknown. In this work, the antioxidant potential of its methanolic, 55% ethanolic, aqueous extracts and crude polysaccharide was evaluated in different systems. The results showed that polysaccharide was the most effective in scavenging ability on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals, metal chelating activity and reducing power, with EC50 values of 0.02, 2.79, 1.29, and 1.82 mg/mL, respectively. Therefore, we further studied the anti-hypoxic activity of crude polysaccharide. The results turned out that polysaccharide (300 mg/kg) prolonged the survival time, decreased the blood urea nitrogen and lactic acid content as well as increased the liver glycogen significantly, compared with the blank control and the commercialized product Hongjingtian (p < 0.05). With such excellent activities, we purified the polysaccharide and analyzed its molecular weight (120 kDa) as well as monosaccharide components (glucose, fructose and mannose). This study indicated that wild Agaricus bisporus (Lange) Sing. Chaidam had strong potential to be exploited as an effective natural functional food to relieve oxidative and hypoxia stresses.

Antigenotoxic Effect of Trametes spp. Extracts against DNA Damage on Human Peripheral White Blood Cells

Trametes species have been used for thousands of years in traditional and conventional medicine for the treatment of various types of diseases. The goal was to evaluate possible antigenotoxic effects of mycelium and basidiocarp extracts of selected Trametes species and to assess dependence on their antioxidant potential. Trametes versicolor, T. hirsuta, and T. gibbosa were the species studied. Antigenotoxic potentials of extracts were assessed on human peripheral white blood cells with basidiocarp and mycelium extracts of the species. The alkaline comet test was used for detection of DNA strand breaks and alkali-labile sites, as well as the extent of DNA migration. DPPH assay was used to estimate antioxidative properties of extracts. Fruiting body extracts of T. versicolor and T. gibbosa as well as T. hirsuta extracts, except that at 20.0 mg/mL, were not genotoxic agents. T. versicolor extract had at 5.0 mg/mL the greatest antigenotoxic effect in both pre- and posttreatment of leukocytes. The mycelium extracts of the three species had no genotoxic activity and significant antigenotoxic effect against H2O2-induced DNA damage, both in pre- and posttreatment. The results suggest that extracts of these three species could be considered as strong antigenotoxic agents able to stimulate genoprotective response of cells.

Antioxidant, antibacterial and DNA protective activities of protein extracts from Ganoderma lucidum

Crude proteins of cultured mycelia and fruiting bodies of Ganoderma lucidum were investigated for antioxidant, antibacterial and DNA protective activities. It was found that the half maximal inhibitory concentration (IC50) of the mycelia protein and fruiting bodies protein extracts against 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radical (ABTS(•+)) were 2.47 ± 0.01 and 2.77 ± 0.11 μg protein/ml and against 2,2-diphenylpicrylhydrazyl radical (DPPH(•)) were 2.5 ± 0.01 and 3.42 ± 0.01 μg protein/ml, respectively. The ferric reducing-antioxidant power (FRAP) values of those samples were 1.73 ± 0.01 and 2.62 ± 0.01 μmole trolox/μg protein respectively. Protein hydrolysates prepared by pronase exhibited a weaker antioxidant activity. Both crude proteins showed antibacterial activity, whereas only the mycelia protein extract could protect DNA damage by hydroxyl ((•)OH) radicals. This protein extract was partial purified by Diethyl amino ethyl (DEAE)-Sepharose column and Sulfopropyl (SP)-Sepharose column, obtained major protein with molecular weight about 45 kilo Dalton (kDa). In conclusion, G. lucidum protein extracts have promise potential for applications as antioxidant and antibacterial agents.

Chemical compositions and antioxidant activities of polysaccharides from the sporophores and cultured products of Armillaria mellea

Armillaria mellea is a traditional Chinese medicinal and edible mushroom. Many cultured products of A. mellea have been used to develop commercial medicines in recent years. The chemical composition and activities of the major bioactive chemical components—polysaccharides—may be different because of differences in the raw materials used. Four polysaccharides (SP, CMP, CFBP and CFMP) were obtained from wild sporophores and cultured products (including mycelia, fermentation broth and fermentation mixture) of A. mellea. Their yields, carbohydrate contents, monosaccharide compositions, FT-IR spectra, NMR spectroscopy and antioxidant activities were investigated. All of the polysaccharides were composed of xylose, glucose and galactose without protein. Glucose was the dominant monosaccharide in SP, CMP and CFMP, whereas galactose was the dominant monosaccharide in CFBP. SP and CMP showed higher scavenging DPPH^• and ABTS^•+ activities and reducing power among four polysaccharides. The carbohydrate content and corresponding glucose percentage were positive influences on the antioxidant activities, whereas the corresponding xylose and galactose percentage were negative influences. A. mellea polysaccharides are potential natural antioxidants. Polysaccharides from cultured products, especially mycelia, are good substitutes for SP and are also potential sources for both dietary supplements and food industries.