Use of whey permeate for cultivating Ganoderma lucidum mycelia

A novel approach to utilizing whey permeate, the cultivation of mycelia of the edible mushroom Ganoderma lucidum, is introduced. The major objective of this research was to use whey permeate as an alternative growth medium for the cultivation of mycelia of edible mushroom G. lucidum and to find an optimum condition for solid-state cultivation. Response surface analysis was applied to determine the combination of substrate concentration (25 to 45 g of lactose/L), pH (3.5 to 5.5), and temperature (25 to 35°C) resulting in a maximal mycelial growth. The radial extension rates, estimated by measuring the diameters of growing colonies on the Petri dishes, were used as the growth of the mycelia at different conditions. In the model, pH and temperature significantly affected mycelial growth, but lactose concentration did not. The condition predicted to maximize the radial extension rate of 17.6 ± 0.4 mm/d was determined to be pH 4.4 and temperature 29.4°C. Therefore, the results suggest that whey permeate could be utilized as a growth substrate for the cultivation of mycelia from the edible mushroom G. lucidum, enhancing the use of this by-product by the cheese manufacturing industry.     

Effect of nanocomposite-based packaging on storage stability of mushrooms (Flammulina velutipes)

In this study, a polyethylene (PE) packaging material that contained nano-Ag, nano-TiO₂, nano-SiO₂, and attapulgite was prepared and its effect on storage stability of mushrooms (Flammulina velutipes) was investigated. The results showed that the nanocomposite-based packaging material (Nano-PM) regulated oxygen and carbon dioxide level, eliminated ethylene and inhibited the growth of microbes, which is a benefit on preservation quality of mushrooms, compared to the normal PE material (Normal-PM). After 14 days of storage, mushroom weight loss, mushroom cap opening, stipe elongation and respiration of Nano-PM stored mushroom were significantly (P < 0.05) inhibited. Furthermore, treatment with the Nano-PM improved the retention of vitamin C, soluble protein, and total soluble solids contents of F. velutipes. The results therefore are promising for the preservation of F. velutipes in order to expand its shelf life and improve its preservation quality by use of this Nano-PM.Industrial relevanceFlammulina velutipes, also named as golden needle mushroom, is one of the most popular edible mushrooms worldwide. Its production and consumption ranked the fourth place among all edible mushrooms in the world. However, fresh golden needle mushrooms are highly perishable. Therefore, preserving freshness of the mushrooms is the main objective of postharvest technology. In the present study, we developed a new type of effective and economic nanoparticle packaging materials and applied it to mushroom preservation. A local company (Jiangsu Tianfeng Biological Technology Co., Ltd) producing mushrooms has started to use this nano-preservation technology during the postharvest transportation and sales. In conjunction with the results of present research, we suggests that nano-composite based packaging materials is a good way for preserving fresh mushrooms and has the potential to be commercialized.     

Cultivation of the shiitake mushroom (Lentinus edodes) on lignocellulosic waste

The Shiitake mushroom (Lentinus edodes) was successfully grown and fruited on a substrate containing 7 parts hardwood sawdust and 3 parts oatmeal. Colonised blocks of substrate placed in a fruiting environment produced edible mushrooms in 9–15 days with an average total yield of c. 135% fresh weight mushrooms per unit dry weight of substrate. The mushroom fruited when daily temperatures ranged between 11 and 26°C.     

Chemical composition,antioxidant and anti-inflammatory properties for ethanolic extracts from Pleurotus eryngii fruiting bodies harvested at different time

Pleurotus eryngii, a popular edible mushroom in Taiwan, is usually cultivated using sawdust medium packing bags through several procedures including culture medium confection, bagging and sterilization, spawn inoculation, fostering mycelia, full growth of mycelia, and inducing fruiting body formation. In this study, P. eryngii commercial products harvested at the 10th, 12th and 15th days after inducing the fruiting body formation were extracted with ethanol, individually. Through determination of chemical composition, antioxidant and anti-inflammatory properties of these extracts, the optimal harvest time of P. eryngii fruiting bodies with higher functional attributes was revealed. The earlier harvested sample extracts had higher effects for scavenging 2,2-diphenyl-1-picrylhydrazyl radicals, reducing power, chelating power, and β-carotene bleaching inhibition, as well as down-regulating lipopolysaccharide-stimulated nitric oxide, prostaglandin E₂, inducible nitric oxide synthase, and cyclooxygenase-2 expression in RAW264.7 macrophages. These functional responses were closely related to levels of phytochemical components including phenolic acids, flavonoids, tocopherols and carotenoids.     

Contents of cadmium,mercury and lead in edible mushrooms growing in a historical silver-mining area

Three harmful metals were determined using AAS techniques in 285 samples of fruiting bodies of 15 wild-growing edible mushroom species. The mushrooms were collected from a forest on the fringe of a historical area of silver mining. The metals were also determined in a topsoil organic layer sampled from nine sites within the observed area. As compared to background levels from unpolluted sites from several European countries, cadmium contents were considerably elevated in nearly all the tested species; lead contents were increased in most of the species, while mercury contents were elevated only in certain species. Thus, many species from the observed area may contribute considerably to the body burden of the metals. Agaricus silvaticus accumulated cadmium extremely and Lepista nuda accumulated mercury. There were no obvious simple positive relationships between the contents of the observed metals in fruiting bodies and the contents of total metals in the soil organic layer.     

Short communication: Cultivation of Lentinus edodes mycelia using whey permeate as an alternative growth substrate

The major objective of this research was to use whey permeate as an alternative growth medium for the cultivation of mycelia of the edible mushroom Lentinus edodes and to find an optimum condition for solid-state cultivation. Response surface analysis was applied to determine the combination of substrate concentration (40 to 60 g of lactose/L), temperature (20 to 30°C), and pH (4 to 6) resulting in a maximal mycelial growth rate. The radial extension rates, estimated by measuring the diameters of growing colonies on the Petri dishes, were used as the growth rate of the mycelia at different conditions. The conditions predicted to maximize the mycelial growth of 6.41 ± 0.47 mm/d were determined to be 40 g of lactose/L, temperature 23.6°C, and pH 5.0. It was concluded that a partial cubic equation could accurately model the response surface of, and predict optimal growth conditions for, L. edodes mycelia using whey permeate because the model prediction agreed with the experimental growth rate, 6.39 ± 0.22 mm/d. The results suggest that whey permeate could be utilized as a growth substrate for the cultivation of mycelia from the edible mushroom L. edodes, enhancing the use of this by-product by the cheese manufacturing industry.     

Cultivation and chemical composition of the paddy-straw mushroom (Volvariella volvaceae)

The cultivation of the paddy-straw mushroom (Volvariella volvaceae) was investigated. Four spawn media for growing V. volvaceae were tested. The presence or absence of urea and the use of barley or sorghum had no effect on the mycelial growth. The addition of yeast extract to the barley grain medium gave heavy growth of mycelium as compared with other media. Seven different media were prepared for the cultivation of paddy-straw mushroom, using local materials such as orange juice waste, rice straw, bagasse, pea-canning waste, horse manure and molasses. The media containing orange juice waste, bagasse, rice straw, horse manure, molasses and urea gave the highest yields of mushroom (5.029 and 4.3 kg/m²). The chemical analysis of mushrooms harvested from orange juice waste-bagasse medium was as follows (percentage on dry weight basis): 4.92 total nitrogen, 1.64 non-protein nitrogen, 2.71 ether extract, 17.4 crude fibre, 6.07 reducing sugars, 4.23 non-reducing sugars, 19.2 starch, 5.29 glycogen, 9.86 mannitol and 12.6 ash. Of fourteen amino acids present, seven are essential, while methionine, arginine, histidine and serine are absent. Tryptophan concentration ($\text{14.7}\text{g}\text{100}\text{g}$ protein) was higher than in any other wild mushroom or legume seed.     

The uptake of cadmium and zinc by mycelia and their accumulation in mycelia and fruiting bodies of edible mushrooms

 Cd and Zn concentrations were determined by optical emission spectroscopy in various parts of the fruiting body and the mycelium of two wild mushrooms, Agaricus macrosporus and Agaricus silvicola, and in cultivated Stropharia rugosoannulata. Cd was distributed in a characteristic manner within the fruiting body of all three species. The Cd content of the cap was a function of its radius as well as its height. Concentrations of Cd and the chemically related Zn in the investigated mushroom segments were strongly correlated, whereas Al, Cu and Ag correlated poorly with Cd. To our knowledge, this is the first study of Cd contents in wild mycelia. We found similar concentrations of Cd and Zn in isolated mycelia and stems of the corresponding fruiting bodies. In addition, substrates were analysed to study soil-specific effects on Cd accumulation. The extent of Cd and Zn transfer from soil to mushroom was species-specific and influenced by the availability of these two heavy metals, as well as the age of the mushroom. Interestingly, the typical Cd and Zn distributions described here were not affected by the extent of accumulation, indicating that uptake and distribution of Cd and Zn are actually two separate mechanisms. Received: 20 October 1998 / Revised version: 11 January 1999     

Isolation and quantitative determination of ergosterol peroxide in various edible mushroom species

Ergosterol peroxide, the steroidal derivative with cytotoxic activity, has been isolated for the first time from the mycelium of edible and medicinal mushroom Hericiumerinaceum (lion’s mane mushroom) together with erinacine A. The new densitometric method was applied for the quantitative determination of ergosterol peroxide in n-hexane extracts of H. erinaceum, Laetiporus sulfureus (chicken mushroom), and Morchella esculenta (common morel) mycelia, as well as in Boletus edulis (king bolete), Suillus bovinus (Jersey cow mushroom), and B. badius (bay bolete) fruiting bodies. The ergosterol peroxide content reached 15.98 ± 0.78, 10.07 ± 0.75, 13.37 ± 0.56, 29.32 ± 1.43, 17.27 ± 0.84, and 12.60 ± 0.59 mg per 100 g, respectively. What is significant was that ergosterol peroxide was identified for the first time, to the best of our knowledge, in edible mushrooms mentioned above.     

Analysis of indole compounds in edible Basidiomycota species after thermal processing

Methanolic extracts of processed fruiting bodies of six edible mushroom species (Basidiomycota) - Armillaria mellea, Boletus badius, Boletus edulis, Cantharellus cibarius, Lactarius deliciosus collected from natural habitats and Pleurotus ostreatus of commercial origin - were analysed for the presence of non-hallucinogenic indole compounds. Thermal processing was designed in such a way that it mimicked conditions used for cooking of mushroom dishes, since only a narrow group of mushrooms can be eaten raw, while indole compounds are thermolabile. All processed extracts were shown to contain l-tryptophan (up to 8.92 mg/100 g dw). The contents of the remaining compounds, 5-methyltryptophan, tryptamine, melatonin, indoleacetonitrile and indole, varied in different species (from 0.71 to 6.55 mg/100 g dw). Extract of processed C. cibarius fruiting bodies contained l-tryptophan, 5-methyltryptophan, tryptamine, melatonin, indoleacetonitrile and indole (1.96-4.94 mg/100 g dw) whereas l-tryptophan (2.78 mg/100 g dw) and tryptamine (2.77 mg/100 g dw) were the only indole compounds identified in the processed fruiting bodies of A. mellea.     

Metal concentration of wild edible mushrooms in Soguksu National Park in Turkey

Twelve varieties of fruiting bodies of wild edible mushrooms collected in 2002 from Soguksu National Park, Ankara, Turkey were analysed for Pb, Cd, Zn, Fe, Mn, Cu, Cr, Ni, and Co contents by inductively coupled plasma optical emission spectrometry (ICP-OES). Dried samples were dissolved by microwave digestion. The contents of trace metals in the mushroom samples were found in the ranges: 0.7–4.2, 0.31–54.2, 29–146, 138–1714, 10–77, 6–187, not detected–21.6, 0.7–4.2 and not detected–5.2 mg kg⁻¹ for Pb, Cd, Zn, Fe, Mn, Cu, Cr, Ni and Co, respectively. The levels of Pb and Cd analysed in all edible mushroom samples except Agaricus arvensis and Ramaria obtusissima for Cd were found to be lower than the legal limits.     

Value‐added use of mushroom ergothioneine as a colour stabilizer in processed fish meats

BACKGROUND: Ergothioneine (ESH), a potent antioxidant, has been found in certain edible mushrooms. Our previous research showed that ESH extracted from the edible mushroom Flammulina velutipes has a positive effect on the colour stability of beef and tuna meat. The purpose of the present study was to compare the efficacy and applicability of ESH extracts prepared from different mushroom species as a colour stabilizer in fish meats. RESULTS: Levels of ESH higher than 2.8 mg mL^?1 were found in extracts prepared from the fruiting bodies of F. velutipes, Lentinula edodes, Pleurotus cornucopiae and Pleurotus eryngii and the processing waste of F. velutipes. When 1 mL of each of the extracts was added to 100 g of minced bigeye tuna and yellowtail meats, the bright‐red colour remained after 5 and 2 days, respectively, of ice storage. The anti‐discoloration efficacy of 1 mL of the extracts prepared from 10 g of the fresh waste portion of F. velutipes was similar to that of its fruiting body or 0.5 g kg^?1 of sodium ascorbate when added to 100 g of minced bigeye tuna meat under ice storage. CONCLUSION: The results of this study clearly showed that ESH prepared from different mushroom species stabilized the colour of fish meats, and the extract from the F. velutipes was the most effective. Copyright © 2010 Society of Chemical Industry     

Effects of extraction solvents,cooking procedures and storage conditions on the contents of ergothioneine and phenolic compounds and antioxidative capacity of the cultivated mushroom Flammulina velutipes

Edible mushrooms contain considerable amounts of the potent natural antioxidant 2‐thiol‐l ‐histidine‐betaine (l ‐ergothioneine, ESH). The objective of this study was to evaluate the effects of extraction solvents, common cooking methods and storage conditions on the ESH content, total phenols (TPs) and antioxidant capacity of the edible mushroom Flammulina velutipes fruiting body and its hot water extract that had been stored at different temperatures. Regarding cooking procedures, boiling in water resulted in the highest losses of antioxidant activity of both ESH and TPs. Most of the losses of ESH and TPs were detected in the cooking water. The ESH contents in the raw mushroom fruiting bodies significantly decreased after 8 days of refrigerated storage under both dark and fluorescent lighting conditions. However, the TP content in the raw mushroom stored under fluorescent lighting significantly increased during 10 days of refrigeration. In contrast, the ESH and TP contents as well as DPPH radical scavenging ability of the fruiting bodies remained unchanged for up to 15 days of frozen storage at ?18 °C. The same behaviour was obtained with the mushroom extract packed in plastic tubes. The correlation between DPPH radical scavenging activity and ESH contents was higher than that for TP compounds.     

Nutritional requirements of Volvariella speciosa (Fr. Ex. Fr.) Singer,a Nigerian edible mushroom

Nutritional requirement studies were carried out on synthetic and semi-synthetic media, as well as different agro-industrial wastes, to evaluate vegetative growth of Volvariella speciosa (Fr. Ex. Fr.) Singer, a Nigerian edible mushroom. The optimum temperature that supported the best growth of this fungus was 30 °C while the optimum pH was 6.0. The moisture contents were observed to vary with different substrates. The best vegetative growth was obtained at 40% moisture content, on sawdust, while it was 80% on Andropogon gianus straw. Among the different media used, the best mycelial extension (92.0 mm) was observed on semi-synthetic, potato dextrose agar while the least growth (74.0 mm) was recorded on laboratory formulated sorghum agar. Maize and A. gianus straw stimulated the best mycelial extension (92.0 mm) while fresh and fermented horse dung supported moderate growths of 70.0 and 67.0 mm, respectively. The least growth (36.0 mm) was observed on fresh cow dung. These findings are discussed in relation to the cultivation of V. speciosa in Nigeria.     

The fate of Cry1Ac Bt toxin during oyster mushroom (Pleurotus ostreatus) cultivation on transgenic Bt cottonseed hulls

BACKGROUND: In China, mushrooms are often cultivated on cottonseed hulls, and spent substrates from their cultivation are used as cattle feed. As the area planted to Bacillus thuringiensis (Bt) cotton in China increases, hulls from transgenic Bt cottonseed are being increasingly used as a substrate for edible mushroom cultivation. The objective of this research was to determine whether Bt toxin was transmitted to mushrooms cultivated on transgenic Bt cottonseed hulls or retained in the spent substrate. RESULTS: Bt toxin was still present in transgenic Bt cottonseed hulls after chemical (carbendazol) treatment but not after heat (100 °C) treatment before mushroom fungus inoculation. When mushroom was cultivated on carbendazol‐treated substrates, Bt toxin level in the substrates fell below the detection limit (1.5 ng Cry1Ac per g fresh weight) in 15 days. CONCLUSION: Bt toxin was not transmitted to mushrooms during cultivation on transgenic Bt cottonseed hulls. Copyright © 2007 Society of Chemical Industry     

Antioxidant properties of phenolic compounds occurring in edible mushrooms

Total phenolic and flavonoid contents occurring in eight types of edible mushrooms (Agaricus bisporus, Boletus edulis, Calocybe gambosa, Cantharellus cibarius, Craterellus cornucopioides, Hygrophorus marzuolus, Lactarius deliciosus and Pleurotus ostreatus) have been respectively evaluated by the Folin–Ciocalteau assay and by the colorimetric reaction with NaNO₂ and AlCl₃ in a basic media. Generally, the assayed mushrooms contained between 1 and 6 mg of phenolics per gram of dried mushroom, depending on the species, while the flavonoid concentrations ranged between 0.9 and 3.0 mg per gram of dried matter. The profile and concentration of individual phenolics was determined by means of high performance liquid chromatography. Homogentisic acid was the free phenolic acid significantly present in all mushrooms although the content varied considerably among the analysed species. Flavonoids, such as myricetin and catechin were also detected in the mushrooms studied. The antioxidant properties of the methanolic extracts from mushrooms were evaluated by monitoring the linoleic acid autoxidation, and all the mushrooms species showed inhibition, with C. cibarius being the most effective against lipid oxidation (74% of inhibition) and A. bisporus the species with lowest antioxidant activity (10% of inhibition).     

Effect of physico-chemical factors and semi-synthetic media on vegetative growth of Lentinus subnudus (Berk.), an edible mushroom from Nigeria

Attempts were made to investigate the effect of different semi-synthetic growth media, pH, temperature, carbon and nitrogen compounds, as well as additives, on vegetative growth of L. subnudus (Berk.), an edible mushroom from Nigeria. The best mycelial extensions (92.7 and 92. mm) were obtained on potato dextrose agar (PDA) and yellow corn agar (YCA), respectively. Moderate growths (87.0, 85.0 and 80.0 mm) were observed on white corn agar (WCA), yeast extract agar (YEA) and malt extract agar (MEA), respectively, but least growth (38.6 mm) was recorded on ‘Ife brown’ beans agar (IBBA). This fungus grew within a temperature range of 15–40 °C (optimum 30 °C) and, pH range of 5.0–8.0 (optimum 5.5).     

Screening of edible mushrooms and extraction by pressurized water (PWE) of 3-hydroxy-3-methyl-glutaryl CoA reductase inhibitors

The methanol/water and particularly the water extracts obtained from 26 mushroom species were able to inhibit the 3-hydroxy-3-methyl-glutaryl CoA reductase (HMGCR) activity to different extent (10–76%). Cultivated mushrooms such as Pleurotus sp. and Lentinula edodes were among the strains which showed higher HMGCR inhibitory capacities. Their inhibitory properties were not largely influenced by cultivation parameters, mushroom developmental stage or flush number. The HMGCR inhibitory activity of L. edodes was concentrated in the cap excluding the gills while in Pleurotus ostreatus it was distributed through all the different tissues. A method to obtain aqueous fractions with high HMGCR inhibitory activity was optimized using an accelerated solvent extractor (ASE) by selecting 10.7 MPa and 25 °C as common extraction conditions and 5 cycles of 5 min each for P. ostreatus fruiting bodies and 15 cycles of 5 min for L. edodes suggesting that the potential HMGCR inhibitors are different in the two selected mushrooms.     

Comparison of free amino acid,carbohydrates concentrations in Korean edible and medicinal mushrooms

Ten popular species of both edible and medicinal Korean mushrooms were analysed for their free amino acids and disaccharides. The average total free amino acid concentration was 120.79 mg g⁻¹ in edible mushrooms and 61.47 mg g⁻¹ in medicinal mushrooms, respectively. The average total of free amino acids for all mushrooms, edible mushrooms and medicinal mushrooms was 91.13 mg g⁻¹. Agaricus blazei (227.00 mg g⁻¹) showed the highest concentration of total free amino acids; on the other hand, Inonotus obliquus (2.00 mg g⁻¹) showed the lowest concentration among the 10 species of mushrooms. The average total carbohydrates concentration was 46.67 mg g⁻¹ in the 10 species of mushrooms, where the edible mushrooms contained 66.68 mg g⁻¹ and the medicinal mushrooms contained 26.65 mg g⁻¹. The carbohydrates constituents of the 10 mushroom species were mainly mannose (36.23%), glucose (34.70%), and xylose (16.83%).     

Formation of genotoxic 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP) and its kinetics in a model system

The nutritional and medicinal potential (antioxidant and antibacterial activities) of 2 wild edible mushroom species (Lentinus sajor-caju and Lentinus torulosus) of Similipal Biosphere Reserve were determined. The macronutrient profile of these mushrooms in general revealed high source of protein (27.31–28.36 g/100 g), carbohydrate (64.95–68.24 g/100 g), and low amounts of fat (1.36–2.42 g/100 g) and possessed good quantities of micronutrients (vitamins and carotenoids) and minerals (P, K, Mn, Ni, and Fe). The solvent extracts (ethanol, methanol, and water) of the mushrooms exhibited strong antioxidant properties (ABTS, DPPH, H₂O₂, and metal chelating activities) with scavenging activity upto 70.54% along with phenol, flavonoid, and total antioxidant capacity. Both the mushrooms showed moderate antibacterial activity (11.0–18.33 mm inhibition zones) against Streptococcus aureus and Vibrio cholerae. Being a rich source of nutritional and medicinal potential, these 2 studied mushrooms can be used in human diet as nutraceuticals and functional foods.