Mushroom-Derived Medicine? Preclinical Studies Suggest Potential Benefits of Ergothioneine for Cardiometabolic Health.

Medicinal use of mushrooms has been documented since ancient times, and in the modern world, mushrooms have a longstanding history of use in Eastern medicine. Recent interest in plant-based diets in Westernized countries has brought increasing attention to the use of mushrooms and mushroom-derived compounds in the prevention and treatment of chronic diseases. Edible mushrooms are the most abundant food sources of the modified amino acid, ergothioneine. This compound has been shown to accumulate in almost all cells and tissues, but preferentially in those exposed to oxidative stress and injury. The demonstrated cytoprotectant effect of ergothioneine has led many to suggest a potential therapeutic role for this compound in chronic conditions that involve ongoing oxidative stress and inflammation, including cardiovascular and metabolic diseases. However, the in vivo effects of ergothioneine and its underlying therapeutic mechanisms in the whole organism are not as clear. Moreover, there are no well-defined, clinical prevention and intervention trials of ergothioneine in chronic disease. This review highlights the cellular and molecular mechanisms of action of ergothioneine and its potential as a Traditional, Complementary and Alternative Medicine for the promotion of cardiometabolic health and the management of the most common manifestations of cardiometabolic disease.

Examining the health effects and bioactive components in Agaricus bisporus mushrooms: a scoping review.

There is evidence from both in vitro and animal models that the consumption of edible mushrooms has beneficial effects on health. It is unclear whether similar effects exist in humans and which bioactive compounds are present. This review synthesises the evidence on the world's most commonly consumed mushroom, Agaricus bisporus to (i) examine its effect on human health outcomes; and (ii) determine the nutrient density of its bioactive compounds, which may explain their health effects. A systematic literature search was conducted on the consumption of A. bisporus, without date and study design limits. Bioactive compounds included ergosterol, ergothioneine, flavonoids, glucans and chitin. Two authors independently identified studies for inclusion and assessed methodological quality. Beneficial effects of A. bisporus on metabolic syndrome, immune function, gastrointestinal health and cancer, with the strongest evidence for the improvement in Vitamin D status in humans, were found. Ultraviolet B (UVB) exposed mushrooms may increase and maintain serum 25(OH)D levels to a similar degree as vitamin D supplements. A. bisporus contain beta-glucans, ergosterol, ergothioneine, vitamin D and an antioxidant compound usually reported as flavonoids; with varying concentrations depending on the type of mushroom, cooking method and duration, and UVB exposure. Further research is required to fully elucidate the bioactive compounds in mushrooms using vigorous analytical methods and expand the immunological markers being tested. To enable findings to be adopted into clinical practice and public health initiatives, replication of existing studies in different population groups is required to confirm the impact of A. bisporus on human health.

The Biosynthetic Pathway of Ergothioneine in Culinary-Medicinal Winter Mushroom, Flammulina velutipes (Agaricomycetes).

Ergothioneine is a natural 2-thiol-amidazole amino acid that plays an important role in inflammation, depression, and cardiovascular disease. Flammulina velutipes is a common basidiomycete mushroom rich in ergothioneine (EGT). However, the biosynthetic pathway of EGT in F. velutipes is still unclear. In this study, the F. velutipes ergothioneine biosynthetic gene 1 (Fvegtl), F. velutipes ergothioneine biosynthetic gene 2 (Fvegt2), and F. velutipes ergothioneine biosynthetic gene 3 (Fvegt3) were cloned and expressed, and the activities of the proteins encoded by these three genes (FvEgt1, F. velutipes ergothioneine biosynthase 1; FvEgt2, F. velutipes ergothioneine biosynthase 2; and FvEgt3, F. velutipes ergothioneine biosynthase 3) were identified. The results showed that FvEgtl not only has the function of methyltransferase, but also has the function of hercynlcysteineteine sulfoxide (Hersul) synthase, which can catalyze the production of Hersul from histidine and cysteine in F. velutipes. FvEgt2 and FvEgt3 are two functionally different cysteine desulfurase enzymes. Among them, FvEgt2 is a cysteine-cysteine desulfurase-which catalyzes the activation of the S-H bond on cysteine, while FvEgt3 is a pyridoxal phosphate (PLP)-dependent cysteine desulfurase responsible for catalyzing the production of ketimine complex. Our results show that FvEgt1/FvEgt2/FvEgt3 can simultaneously catalyze the production of EGT by histidine, cysteine, and pyridoxal phosphate. Collectively, the in vitro synthesis of EGT in the edible fungus F. velutipes was first achieved, which laid the foundation for the biological production of EGT.

A Study on the Antioxidant Properties and Stability of Ergothioneine from Culinary-Medicinal Mushrooms.

The naturally occurring amino acid ergothioneine (EGT) has excellent free radical scavenging ability, which was not different to ascorbic acid. The IC50 values for EGT scavenging hydrogen peroxide, hydroxyl radicals, and superoxide anions were 11.65 ± 0.31, 70.31 ± 1.59, and 160.44 ± 0.32 µg/mL, respectively. The EGT concentration in different species of mushrooms was significantly different (p < 0.05), but it was not significantly related to the ability of the mushrooms to scavenge reactive oxygen species (p > 0.05). After isolating EGT from mushrooms, we demonstrated that the antioxidant ability of EGT accounts for about 25% of the total antioxidant ability of the extract. We studied the stability of EGT and found that it has excellent light, thermal, and acid-base stability. However, the presence of Cu2+ decreased the concentration of EGT. Unlike EGT, the thermal stability of the EGT extracted from Pleurotus citrinopileatus (PEGT) was not as good as EGT, while long-term high-temperature heating caused a decrease in the concentration of PEGT. The results of our study provide a basis for further investigating EGT from mushrooms for research and development.

Effects of Ergothioneine-Rich Mushroom Extract on the Oxidative Stability of Astaxanthin in Liposomes.

Ergothioneine-rich crude extracts of Pleurotus cornucopiae were used as a source of antioxidative components to control the effects of lipid oxidation in astaxanthin-containing liposomes. This study aimed to elucidate the interactions of liposomal astaxanthin and lipids with ergothioneine-rich mushroom extract (ME) under radical oxidation-induced conditions to provide a better understanding of the agricultural and postharvest applications of this strategy. Azo compounds (2,2'-azobis(2-methylpropionamidine) dihydrochloride and 2,2'-azobis(2,4-dimethylvaleronitrile) were used as hydrophilic and lipophilic radical initiators, respectively. Results of this study demonstrate that the presence of ME significantly delayed the oxidative degradation of astaxanthin and controlled the progress of lipid oxidation in a liposomal system. The lipid hydroperoxide formation was significantly suppressed, while polyunsaturated fatty acids were protected from degradation. In addition, Crude ME also demonstrated more potent DPPH radical scavenging activities and EC50 than the equimolar concentrations of ergothioneine alone, which suggested the presence of additional compounds with antioxidative properties.

Extraction of Ergothioneine from Pleurotus eryngii and P. citrinopileatus (Agaricomycetes) and Preparation of Its Product.

Ergothioneine is an effective antioxidant and is abundant in species of genus Pleurotus. This research focused on developing an ergothioneine extract from P. eryngii and P. citrinopileatus under optimal extraction conditions. The hot-water and 70% ethanol extractions yielded more ergothioneine than microwave, ultrasonic, and autoclaving extractions. Hot-water extraction with optimal conditions-125 rpm at 75°C for 5 minutes-produced P. eryngii and P. citrinopileatus extracts with 0.86 and 3.73 mg ergothioneine/g dry weight, respectively. In addition to 50% of added maltodextrin, spray-dried products from mushrooms contained 23.07-16.58% carbohydrates and 18.32-21.40% protein. The microstructure of spray-dried products showed shrunken spheres with mean particle diameters of 15.82-19.94 µm. After in vitro simulated gastric and intestinal digestion, the spray-dried P. eryngii and P. citrinopileatus products contained 88% and 91% residual ergothioneine, respectively. Overall, the spray-dried products could be used as antioxidative supplements.

A comprehensive screening shows that ergothioneine is the most abundant antioxidant in the wild macrofungus Phylloporia ribis Ryvarden.

The polar and non-polar extracts from the authenticated wild mushroom Phylloporia ribis were separated by hydrophilic interaction liquid chromatography (HILIC) and by reverse phase (RP)-HPLC, respectively. A split valve separated the eluents into two fractions for free-radical scavenging analysis and for structural identification. Forty-six compounds showed scavenging activity of the stable-free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). The structures of 8 antioxidants (inosine, caffeic acid, ergothioneine, p-hydroxybenzoic acid, adenosine, 3,4-dihydroxybenzaldehyde, apigenin, and naringenin) are characterized by Mass Spectrometer. Among them, ergothioneine was the most abundant (>65%) and most active antioxidant in P. ribis.

Antioxidant properties of fruiting bodies, mycelia, and fermented products of the culinary-medicinal king oyster mushroom, Pleurotus eryngii (higher Basidiomycetes), with high ergothioneine content.

The culinary-medicinal king oyster mushroom Pleurotus eryngii is known to contain ergothioneine, and its products, including fruiting bodies, mycelia, and solid-state fermented products (adlay and buckwheat), were prepared to study their antioxidant properties. Fruiting bodies, regular and Hi-Ergo mycelia, and fermented products contained 2.05, 1.68, 5.76, 0.79-0.80 mg/g of ergothioneine, respectively. On the basis of the results obtained, P. eryngii products had effective antioxidant activity, reducing power, and scavenging ability on 1,1-diphenyl-2-picrylhydrazyl radicals and chelating ability on ferrous ions. Hi-Ergo mycelia was the most effective in the first 3 antioxidant properties in addition to its ergothioneine content. In addition, fruiting bodies were more effective in all antioxidant properties than regular mycelia. For ethanolic and hot water extracts from mycelia and fruiting bodies, the correlation coefficients between total phenol contents and each antioxidant attribute were 0.483-0.921. Overall, P. eryngii products with high amounts of ergothioneine could be used beneficially as a functional food.

Comparative study of contents of several bioactive components in fruiting bodies and mycelia of culinary-medicinal mushrooms.

Mushrooms (including fruiting bodies and mycelia) contain several bioactive components such as lovastatin, γ-aminobutyric acid (GABA), and ergothioneine. This article reports the results of 49 samples, including 9 fruiting bodies, 39 mycelia, and 1 vegetative cell, of 35 species of culinary-medicinal mushrooms from 18 genera: Agaricus, Agrocybe, Coprinus, Cordyceps, Cyathus, Daedalia, Flammulina, Fomes, Ganoderma, Grifola, Laetiporus, Lentinus, Morchella, Ophiocordyceps, Pleurotus, Trametes, Tremella, and Verpa. The results show that Cyathus striatus strain 978 contained the highest amount of lovastatin (995.66 mg/kg) in mycelia. Among fruiting bodies, 6 samples contained a high amount of GABA (274.86-822.45 mg/kg), whereas among mycelia, contents of GABA in 27 samples ranged from 215.36 to 2811.85 mg/kg. Among mycelia, Pleurotus cornucopiae strain 1101 contained the highest amount of ergothioneine (3482.09 mg/kg). Overall, these 3 bioactive components were commonly found in most mushrooms, and the results obtained might be related to their beneficial effects.

Submerged cultivation of mycelium with high ergothioneine content from the culinary-medicinal king oyster mushroom Pleurotus eryngii (higher Basidiomycetes) and its composition.

The culinary-medicinal king oyster mushroom, Pleurotus eryngii, was used to produce mycelia with high ergothioneine content using a one-factor-at-a-time method. The optimal culture conditions for mycelia harvested at day 14 were 25°C, 10% inoculation rate, 2% glucose, 0.5% yeast extract, and no adjustment to the initial pH value. With histidine or amino acid mix added, biomasses and the ergothioneine content of mycelia were higher than those of the control. The ergothioneine content of mycelia harvested at days 16-20 were higher than that of mycelia harvested at day 14. In addition, the ergothioneine content of mycelia from the fermentor (5.84-5.76 mg/g) was much higher than that of mycelia from the shaken flask (4.93-5.04 mg/g). Mycelia with high ergothioneine content showed a profile of proximate composition similar to that of regular mycelia but lost its characteristic umami taste. Overall, mycelia high in ergothioneine could be prepared by optimal culture conditions, the addition of precursors, prolonged harvest, and aeration in the fermentor.

Functional benefits of ergothioneine and fruit- and vegetable-derived nutraceuticals: overview of the supplemental issue contents.

For good reason, there is increasing interest in assessing the clinical efficacy of dietary supplements, naturally occurring compounds, and nutraceuticals intended for improving health and reducing disease. This is also a pressing interest in mitigating the effects of age-dependent chronic diseases. This opportunity argues for the need to develop a clear understanding of the basic molecular mechanisms responsible for the actions of dietary biofactors that can contribute to the slowing or preventing of diseases and the possibility of enhancing these improvements by coupling them with healthy lifestyle changes.

Preparation of culinary-medicinal king oyster mushroom Pleurotus eryngii-fermented products with high ergothioneine content and their taste quality.

Pleurotus eryngii (DC. : Fr.) Ouel. was used in solid-state fermentation to develop novel mushroom products with a high amount of ergothioneine. The correlation coefficients between ergothioneine content and biomass were 0.8878 and 0.9206 for fermented adlay and buckwheat, respectively. Using optimal conditions, Pleurotus-fermented adlay and buckwheat (PFA and PFB) with the ergothioneine contents of 795.5 and 786.1 mg/ kg, respectively, were prepared. However, mycelia contained the highest ergothioneine content of 1514.6 mg/kg. As a result of SSF by P. eryngii, PFA and PFB contained more taste components than adlay and buckwheat, as evidenced by higher contents of total sugars and polyols, total free amino acids and monosodium glutamate-like components, and total and flavor 5'-nucleotides. In addition, PFB and buckwheat showed comparable equivalent umami concentration (EUC) values, whereas PFA showed a higher EUC value than adlay. Overall, Pleurotus-fermented products with a high amount of ergothioneine will be a novel functional food.

Comparative study of contents of several bioactive components in fruiting bodies and mycelia of culinary-medicinal mushrooms.

Mushrooms have been consumed for thousands of years, and several bioactive components were found therein, including lovastatin, γ-aminobutyric acid (GABA) and ergothioneine. The study reported herein was to analyze these three bioactive components in 15 fruiting bodies and 9 mycelia of 19 species of mushrooms from genera Agaricus, Agrocybe, Auricularia, Boletus, Ganoderma, Hypsizygus, Inonotus, Lentinus, Morchella, Pleurotus, Tremella, Termitomyces, and Volvariella. The results show that Hypsizygus marmoreus contained the highest amount of lovastatin (628.05 mg/kg) in fruiting bodies and Morchella esculenta contained the highest amount (1438.42 mg/ kg) in mycelia. Agaricus brasiliensis contained the highest amount of GABA (1844.85 mg/kg) in fruiting bodies, and mycelia of Boletus edulis, Pleurotus citrinopileatus, and Termitomyces albuminosus contained extraordinarily higher amounts (1274.03, 1631.67, and 2560.00 mg/kg, respectively). Volvariella volvacea contained the highest amount of ergothioneine (537.27 mg/kg) in fruiting bodies and mycelia; Boletus edulis, Pleurotus ferulae, and P. salmoneostramineus contained relatively higher amount of ergothioneine too (258.03, 250.23, and 222.08 mg/kg, respectively). However, none of these components was detected in fruiting bodies of Inonotus obliquus. In conclusion, these three bioactive components were commonly found in most mushrooms, and these results might be related to their beneficial effects.

The metallothionein/thionein system: an oxidoreductive metabolic zinc link.

Metallothioneins (MTs) were discovered more than 50 years ago and identified as low-molecular weight, sulfhydryl-rich proteins that were subsequently found to bind zinc predominantly. The binding of seemingly redox inactive zinc ions allows MT to play a central role in oxidoreductive cellular metabolism, cellular zinc distribution and homeostasis. In this interpretive study, we discuss the interaction of MT with physiologically relevant molecules and its effect on zinc-thiolate bonds. These interactions are linked to recent progress in the functional role of MT in cellular zinc transport, energy production, and protection of the organism against oxidative stress and neurodegenerative diseases.