Antioxidant properties and phenolic profile of the most widely appreciated cultivated mushrooms: A comparative study between in vivo and in vitro samples

The present study reports a comparison of the antioxidant properties and phenolic profile of the most consumed species as fresh cultivated mushrooms and their mycelia produced in vitro: Agaricus bisporus (white and brown), Pleurotus ostreatus (oyster), Pleurotus eryngii (king oyster) and Lentinula edodes (shiitake). The antioxidant activity was evaluated through reducing power (Folin–Ciocalteu and Ferricyanide/Prussian blue assays), free radical scavenging activity (DPPH assay) and lipid peroxidation inhibition (β-carotene/linoleate and TBARS assays). The analysis of phenolic compounds was performed by HPLC/PAD. The mushroom species with the highest antioxidant potential was Agaricus bispous (brown). However, concerning to the species obtained in vitro, it was L. edodes that demonstrate the highest reducing power. Generally, in vivo samples revealed higher antioxidant properties than their mycelia obtained by in vitro techniques. About the phenolic compounds researched, they were detected both in mushrooms and mycelia without any particular abundance. Results showed that there is no correlation between the studied commercial mushrooms and the corresponding mycelia obtained in vitro. Nevertheless, this study contributes to the rise of data relatively to the species consumed as fresh mushrooms and the possibility of their in vitro production as a source of bioactive compounds.     

Studies on the constituents of higher fungi of Korea(XXIII)

The carpophores of three Korean mushrooms,Coriolus versicolor, Pleurotus ostreatus andLentinus edodes were respectively extracted with hot water and the extracts were dialyzed through Visking tube. They were found to exert an antitumor activity against sarcoma-180 implanted in mice. Especially, the inhibition ratio of the extract ofCoriolus versicolor (100 mg/Kg, i.p.) was almost 100%. But all the extracts did not affect the growth of leukemia L5187Y cellsin vitro. Therefore these facts indicate that the extracts appear to stimulate cell-mediated immunity.     

The effects of mushroom components on the proliferation of HeLa cell linein vitro

In order to find out nutritional effects of Korean edible mushrooms on the multiplication of tissue cells, the alcohol extracts and acid hydrolysates of eleven species of mushrooms were added to Earle’s BSS. A comparison of the respective multiplications of HeLa cells in this solution and in control solution of TC-199. Yielded the following results: The alcohol extracts and acid hydrolysates ofCoprinus comatus, Agaricus campestris, Agaricus bisporus, Lentinus edodes, Tricholoma matsutake, Pleurotus ostreatus, Ramaria botrytis andPholiota nameko influenced favorably the maintenance of the normal form and monolayer of HeLa cells. The growth curves of HeLa cells in the cultures containing, respectively, the alcohol extracts and acid hydrolysates of these eight mushrooms showed that five species, i.e.,Coprinus comatus, Agaricus campestris, Agaricus bisporus, Lentinus edodes andTricholoma matsutake effected an excellent multiplication and that the other three species were less effective than those five species. As to the effects on the cell multiplication, no marked difference was observed between the alcohol extracts and the acid hydrolysates of the mushrooms tested.     

Myo- and hepatotoxic effects of cultivated mushrooms in mice

Mushrooms are currently examined for their potential as functional foods. At the same time, novel types of mushroom intoxications, such as rhabdomyolysis after prolonged consumption, have been described in edible species. The aim of the present study was to perform an acute toxicity test to establish if the most commonly cultivated species would have myo- or hepatotoxic effects. Mice (n = 6/group) were exposed to 3, 6 or 9 g Agaricus bisporus, Lentinus edodes or Pleurotus ostreatus kg body mass⁻¹ d⁻¹ for 5 d with 6 controls. Food and water intakes, plasma clinical chemistry and liver and muscle histology were evaluated. While A. bisporus caused significantly increased plasma bilirubin concentrations, L. edodes elicited also increased plasma creatine kinase activities at 9 g kg⁻¹ d⁻¹. P. ostreatus decreased dramatically the food intake but increased the water intake and caused significantly increased plasma alanine aminotransferase activities at 9 g kg⁻¹ d⁻¹. While there were no pathological findings in the histological samples, it seems that the doses and time periods required for the potential benefits of mushroom consumption to appear are similar to those causing undesirable effects. This should be taken into consideration if mushrooms are to be used as functional foods.     

Studies on the constituents of higher fungi of Korea(XXIV)

The carpophores of three Korean mushrooms,Coriolus versicolor, Pleurotus ostreatus, andLentinus edodes were respectively extracted with hot water and the extracts were dialyzed through Visking tube. They were found to contain an antitumor activity against sarcoma-180 implanted in mice. The components of these aqueous extracts were found to be polysaccharide and protein by color reactions including anthrone and Lowry-Folin tests. The hydrolysis of the polysaccharide with 3% HCl-MeOH and trimethylsilylation yielded four monosaccharides: glucose, mannose, galactose and xylose which were identified by G.L.C. After hydrolysis of protein with 6N HCl, fourteen to seventeen amino acids including aspartic and glutamic acids were detected by an amino acid analyzer.     

Comparative study of antioxidant activities and total phenolic content of selected edible wild mushrooms

The present study aims to assess the antioxidant activities (AOA) and total phenolic content (TPC) of water extracts of selected edible wild mushrooms: Pleurotus porrigens, Schizophyllum commune, Hygrocybe conica, and Lentinus ciliatus. The AOA were evaluated against DPPH radical and ABTS radical cation scavenging ability, ferric-reducing antioxidant power (FRAP) and beta-carotene-linoleate bleaching (beta-CB) assays, and the Folin-Ciocalteu method for TPC. BHA was used as reference. P. porrigens showed significantly higher (p < 0.05) DPPH* scavenging ability (90.78 +/- 0.30%) and FRAP (6.37 +/- 0.22 mM FE/100g), while Sch. commune showed significantly higher (p < 0.05) ABTS*+ inhibition activity (94.96 +/- 0.70%) and beta-CB inhibition activity (94.18 +/- 0.17%), respectively. TPC was found in a descending order of P. poriggens > L. ciliatus = Pleurotus ostreatus (cultivated) > H. conica = Sch. commune. Positive correlation was observed between the AOA and TPC. When compared to BHA (2 mM), P. porrigens showed significantly higher (p < 0.05) DPPH* scavenging ability and reducing power, while Sch. commune showed comparable DPPH* scavenging ability and ABTS*+ inhibition activity. All the mushrooms have better ABTS*+ inhibition activity than BHA (1 mM). The beta-CB inhibition activity of BHA was significantly higher than those of edible wild mushrooms. The water extracts of edible wild mushrooms showed potent antioxidant activities compared to BHA to a certain extent.     

Antioxidant properties of extracts of wild medicinal mushroom species from Croatia

Antioxidant activity and total phenol (TP) content of methanol and water extracts of three wild Croatian mushroom species Auricularia auricula-judae (Bull.) Quél., Sarcoscypha austriaca (Sacc.) Boud., and Strobilurus esculentus (Wulfen) Singer were determined and compared with the values obtained for extracts of four cultivated mushrooms Agaricus bisporus (J.E. Lange) Imbach (brown and white strains), Pleurotus ostreatus (Jacq.) P. Kumm., and Lentinus edodes (Berk.) Singer. Spectrophotometric determination of the TP content was performed using the Folin-Ciocalteu method, while antioxidant activity was measured in a reaction with 1,1-diphenyl-2-picrylhydrazyl radical (DPPH assay) and ferric-tripyridyltriazine (Fe3+-TPTZ) complex (FRAP assay). On the average, 5.8-fold higher TP content was observed for water in comparison to methanol extracts of all analyzed mushrooms. Consequently, antioxidant activity was also higher for water extracts, which is evident from the obtained higher values in the FRAP assay and lower EC50 values in the DPPH assay. Among the three tested wild species, the water extract of S. esculentus exhibited the highest concentration of TP, 8.12 mg/g gallic acid equivalents (GAE), the highest reducing power, 19.42 mmol Fe2+/kg, and the best radical scavenging properties, EC50= 13.5 mg/mL.     

Bioactive microconstituents and antioxidant properties of wild edible mushrooms from the island of Lesvos,Greece

Crude composition, fatty acids, sterols, total phenolic content (TPC), individual polyphenols and terpenic acids were determined in five wild edible mushrooms species (Lactarius deliciosus, Lactarius sanguifluus, Lactarius semisanguifluus, Russula delica, Suillus bellinii) from Lesvos Island, Greece. In addition, the DPPH scavenging capacity, the ferric ion reducing power (FRAP) and the ferrous ion chelating activity of mushroom methanolic extracts were assessed. Among sterols, ergosterol predominated at concentrations 9.2–18.0 mg/100 g fw. Total phenolic content of mushroom extracts ranged from 6.0 to 20.8 mg GAE/100 g fw. Up to 19 simple polyphenols were determined in mushrooms extracts, the more abundant being p-OH-benzoic acid, p-OH-phenylacetic acid, o-coumaric acid, ferulic acid and chrysin. In addition, the triterpenic acids oleanolic and ursolic were detected for the first time in mushrooms. All species exerted antioxidant activity and ferrous ion chelating capacity. Principal component analysis revealed good correlations between TPC, DPPH and FRAP but not with metal chelating activity. It seems that mushrooms polyphenols exert antiradical and reducing activities, but they are not strong metal chelators, the observed chelating ability being probably due to other classes of compounds.To our knowledge, this is the first report on the bioactive microconstituents and antioxidant activity of wild Greek edible mushrooms.     

The mutagenicity of edible mushrooms in a histidine-independent bacterial test system

In mutagenicity screening of 40 edible mushroom species, special attention was paid to the selection of the test system, since complex mixtures such as mushroom extracts may interfere with the genetic endpoint of the assay. This paper shows that the weak mutagenicity of some mushrooms in the Ames test, as reported by several authors, is actually an artefact due to the presence of free histidine in the mushroom extracts, which apparently increases the reversion of bacteria from histidine auxotrophy to prototrophy. To avoid amino-acid interaction, a combination of the forward mutation assay to 8-azaguanine resistance in Salmonella typhimurium TM677 and a liquid test was used. Out of 35 wild and commercially grown mushrooms tested, 13 species exhibited mutagenic activity. In the case of the five samples of dried mushrooms, weak mutagenicity could be detected for Auricularia sp. The presence of microsomal enzymes (S-9) reduced the mutagenic effects of all the mushrooms, with the exception of Agaricus abruptibulbus and Cantharellus cibarius, where metabolic activation enhanced the mutagenic activity.     

Nutrients and non-nutrients composition and bioactivity of wild and cultivated Coprinus comatus (O.F.Müll.) Pers.

Mushrooms have been reported as sources of biomolecules with various potential. Coprinus comatus was studied to obtain information about this species, comparing cultivated and wild samples. Free sugars, fatty acids, tocopherols, organic acids and phenolic acids were analyzed by chromatographic techniques coupled to different detectors. C. comatus methanolic extract was tested for its antioxidant potential (reducing power, radical scavenging activity and lipid peroxidation inhibition) and antimicrobial properties (tested towards Gram positive and negative bacteria, and microfungi). The toxicity for liver cells was tested in porcine liver primary cells. Both studied samples revealed similar nutritional value and energy contribution. The cultivated sample revealed the highest content in free sugars, monounsaturated fatty acids and tocopherols, while the wild mushroom was richer in saturated and polyunsaturated fatty acids, organic acids and phenolic compounds. The cultivated species also revealed the highest antioxidant potential and antimicrobial activity (with exception towards Gram negative bacteria and Aspergillus ochraceus). Both species revealed no toxicity towards porcine liver cells. The present study proved that cultivated and wild mushrooms from the same species could be excellent options as food and as sources of nutritional and bioactive compounds. Furthermore, differences in wild and cultivated samples were comparatively investigated for the first time.     

Effect of selenium enrichment on antioxidant activities and chemical composition of Lentinula edodes (Berk.) Pegl. mycelial extracts

Preparations derived from Lentinula edodes (Berk.) Pegl. mycelium are worldwide used as dietary supplements containing compounds active as immune system enhancers, demonstrating chemopreventive and anticancer activity. L. edodes mycelium enriched with organic forms of selenium like selenized yeast possess putative, higher cancer preventive properties. The objective of this study was to test the effect of enrichment in selenium on antioxidant, reducing and free radical scavenging activity of water and alcohol extracts from mycelium of L. edodes (Berk.). To elucidate the cause of enhanced antioxidant activity of extracts, a preliminary selenium speciation by specific oxido-reduction reaction was performed. Se-enrichment enhanced antioxidant activity, reducing power and free radical scavenging effect of mycelial extracts by almost 100–400%. Increase of activity was particularly high for diluted extracts (concentrations 0.1–0.5 mg/ml). The chemical composition of extracts from both Se-enriched and non-enriched mycelium was compared by determination of polyphenols, proteins, carbohydrates and lipids. Results showed that Se-enrichment enhanced antioxidant activities of mycelial extracts, likely by high amounts of organic Se-compounds (–II oxidation state) and elemental red selenium, and by increased polyphenols content. Our results suggest that Se-enrichment is a good method for enhancement of important activities of human dietary supplements, including Shiitake preparations.     

Chemical composition of five wild edible mushrooms collected from Southwest China and their antihyperglycemic and antioxidant activity

Evaluation of the chemical composition and antihyperglycemic and antioxidant activity of five wild edible mushrooms (Clitocybe maxima, Catathelasma ventricosum, Stropharia rugoso-annulata, Craterellus cornucopioides and Laccaria amethystea) from Southwest China. The chemical composition assay includes proximate analysis (moisture, ash, crude protein, crude fat, total carbohydrates and total energy), bioactive compounds analysis (total phenolic, flavonoid, ascorbic acid, ergosterol, tocopherol), fatty acid analysis, amino acid analysis, phenolic compounds analysis and mineral analysis of these mushrooms. Furthermore, assays of α-glucosidase inhibitory and α-amylase inhibitory activity were used for evaluating antihyperglycemic activity of the mushrooms, and assays of reducing power, chelating effect on ferrous ions, scavenging effect on hydroxyl free radicals and 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity were used for evaluating antioxidant activity of the mushrooms. Based on the results, ethanolic and aqueous extract of these mushroom all showed antihyperglycemic and antioxidant potential. In particular, the aqueous extract of C. ventricosum revealed the highest α-glucosidase inhibitory activity (EC50 value 2.74 μg/mL), DPPH radical scavenging activity (EC50 value 2.86 mg/mL) and reducing power (EC50 value 0.96 mg/mL), while the aqueous extract of L. amethystea showed the highest α-amylase inhibitory activity (EC50 value 4.37 μg/mL) and metal chelating activity (EC50 value 2.13 mg/mL).     

Antibacterial Activity of some Medicinal Mangroves against Antibiotic Resistant Pathogenic Bacteria

The antibacterial activity of the leaves and bark of mangrove plants, Avicennia marina, A. officinalis, Bruguiera sexangula, Exoecaria agallocha, Lumnitzera racemosa, and Rhizophora apiculata was evaluated against antibiotic resistant pathogenic bacteria, Staphylococcus aureus and Proteus sp. Soxhlet extracts of petroleum ether, ethyl acetate, ethanol and water were prepared and evaluated the antibacterial activity using agar diffusion method. Most of the plant extracts showed promising antibacterial activity against both bacterial species. However, higher antibacterial activity was observed for Staphylococcus aureus than Proteus sp. The highest antibacterial activity was shown by ethyl acetate of mature leaf extracts of E. agallocha for Staphylococcus aureus. All ethyl acetate extracts showed higher inhibition against S. aureus while some extracts of chloroform, ethyl acetate and ethanol gave inhibition against Proteus sp. None of the petroleum ether and aqueous extracts showed inhibition against Proteus sp. All fresh plant materials did also show more antibacterial activity against both bacterial strains than did dried plant extracts. Antibacterial activity of fresh and dried plant materials reduced for both bacterial strains with time after extraction. Since L. racemosa and A. marina gave the best inhibition for bacterial species, they were used for further investigations. Charcoal treated plant extracts of L. racemosa and A. marina were able to inhibit both bacterial strains more than those of untreated plant extracts. Phytochemical screening of mature leaf, bark of L. racemosa and leaf extracts of A. marina has been carried out and revealed that leaf and bark contained alkaloids, steroids, triterpenoids and flavonoids. None of the above extracts indicate the presence of saponins and cardiac glycosides. Separated bands of extracts by TLC analysis showed antibacterial activity against S. aureus.     

Cadmium in edible mushrooms from NW Spain: Bioconcentration factors and consumer health implications

Mushrooms do not constitute a significant portion of the human diet, but the consumption of wild and cultivated mushrooms has become increasingly in recent years. Some species accumulate high levels of toxic metals, both in unpolluted and polluted areas. In this study, we examined the accumulation capacity of cadmium in edible mushrooms in relation to certain factors and their possible toxicological implications. Cadmium concentrations were determined by an ICP-MS spectrometer in 238 samples of the fruiting bodies of 28 wild and cultivated growing edible mushrooms species and the underlying soil. The hymenophore (H) and the rest of the fruiting body (RFB) were analysed separately. The highest mean cadmium concentration (mg/kg dry weight) was found in Agaricus macrosporus (52.9 in H and 28.3 in RFB). All mushroom species accumulated cadmium in relation to the underlying soils. There were statistically significant differences between the hymenophore and the rest of the fruiting body (p < 0.001). Cadmium concentrations were compared to data in the literature and to levels set by legislation. It was concluded that consumption of our studied mushrooms is not a toxicological risk as far as cadmium content is concerned, although the species A. macrosporus should not be consumed.     

Mutagenicity studies of urine and faecal samples from rats treated orally with the food colourings brown FK and Red 2G

Urine and faecal extracts from rats given Brown FK or Red 2G orally (800 mg/kg body weight) were investigated for mutagenicity. Extracts were subjected to liquid fluctuation and plate incorporation assays with Salmonella typhimurium strains TA98 and TA100 in the presence and absence of liver microsomes and/or a β-glucuronidase-sulphatase preparation. Urine from Red 2G-treated rats only exhibited direct activity when coloured fractions from polyamide-column concentrates were tested with TA100. All other urines, as well as aqueous and ether faecal extracts from animals receiving either colouring, were no more mutagenic than the respective control extracts obtained from the same animals prior to dosing.     

Development and Evaluation of Hepatoprotective Polyherbal Formulation Containing Some Indigenous Medicinal Plants

The present study explores the hepatoprotective activity of various extracts of Ferula asafoetida, Momordica charantia Linn and Nardostachys jatamansi against experimental hepatotoxicity. Polyherbal suspensions were formulated using extracts showing significant activity and evaluated for both physicochemical and hepatoprotective activity in comparison with LIV-52 as standard. Petroleum ether (60-80°), chloroform, benzene, ethanol and aqueous extracts of Ferula asafetida, Momordica charantia Linn and Nardostachys jatamansi were evaluated for hepatoprotective activity against carbon tetrachloride-induced liver toxicity in Wistar rats. Polyherbal suspensions were prepared by the trituration method using a suspending agent and other excipients. Formulation F3 has shown significant hepatoprotective effect by reducing the elevated serum enzyme levels such as glutamate oxaloacetate transaminase, glutamate pyruvate transaminase and alkaline phosphatase. These biochemical observations were supplemented by histopathological examination of liver sections. Various parameters evaluated for all formulations were within the official specifications. Experimental data suggested that treatment with formulation F3 enhances the recovery from carbon tetra chloride-induced hepatotoxicity. From these results it may be concluded that the F3 formulation (containing chloroform, petroleum ether and aqueous extracts of Ferula asafetida, petroleum ether and ethanol extracts of Momordica charantia Linn. and petroleum ether and ethanol extracts of Nardostachys jatamansi) demonstrated significant hepatoprotective activity, that might be due to combined effect of all these extracts.     

Carcinogenic fungal hydrazines.

The carcinogenic, mutagenic and teratogenic activity of 11 hydrazine analogues and diazonium ions are described. These chemicals are ingredients of 22 mushroom species. Of these, one is cultivated, while the remaining 21 are wild fungi. To date, many of these mushrooms are considered to be edible. The appropriate chemistry and biochemistry investigations of the mushroom chemicals are summarized briefly. Human consumption estimates also are provided in as much as possible.     

Evaluation of metal concentration and antioxidant,antimicrobial, and anticancer potentials of two edible mushrooms Lactarius deliciosus and Macrolepiota procera

This study is designed for the determination of metal concentrations, antioxidant, antimicrobial, and anticancer potential of two edible mushrooms Lactarius deliciosus and Macrolepiota procera. Concentrations of nine metals are determined and all metals are present in the allowable concentrations in the tested mushrooms except Cd in M. procera. Antioxidant activity was evaluated by free radical scavenging and reducing power. M. procera extract had more potent free radical scavenging activity (IC₅₀ = 311.40 μg/mL) than L. deliciosus extract. Moreover, the tested extracts had effective reducing power. The total content of phenol in the extracts was examined using Folin–Ciocalteu reagent and obtained values expressed as pyrocatechol equivalents. Further, the antimicrobial potential was determined with a microdilution method on 15 microorganisms. Among the tested species, extract of L. deliciosus showed a better antimicrobial activity with minimum inhibitory concentration values ranging from 2.5 mg/mL to 20 mg/mL. Finally, the cytotoxic activity was tested using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method on human epithelial carcinoma HeLa cells, human lung carcinoma A549 cells, and human colon carcinoma LS174 cells. Extract of both mushrooms expressed similar cytotoxic activity with IC₅₀ values ranging from 19.01 μg/mL to 80.27 μg/mL.     

Total contents of arsenic and associated health risks in edible mushrooms,mushroom supplements and growth substrates from Galicia (NW Spain)

The levels of arsenic (As) in the main commercial species of mushrooms present in Galicia, in their growth substrates, and mushroom supplements have been analysed by ICP-MS, with the intention of assessing potential health risks involved with their consumption.The mean concentrations of As in wild and cultivated mushrooms was 0.27 mg/kg dw, in mushroom supplements 0.40 mg/kg dw, in soils 5.10 mg/kg dw, and in growth substrate 0.51 mg/kg dw.No significant differences were observed between species, although the species Lactarius deliciosus possessed a slightly more elevated mean concentration (at 0.49 mg/kg dw) than the other species investigated. In soils, statistically significant differences (p < 0.05) were observed according to geographic origin. Levels in mushroom supplements, although low, were higher than in wild or cultivated mushrooms.Measured arsenic levels were within the normal range in samples analysed in unpolluted areas. Because of the low As concentrations found in fungi and mushroom supplements from Galicia, and considering the relatively small inclusion of these foods in people’s diet, it can be concluded that there is no toxicological risk of arsenic associated with the consumption of the species of mushrooms analysed or at the dosages indicated for mushroom supplements.