Outdoor versus indoor cultivation: Effects on the metabolite profile of Agaricus subrufescens strains analyzed by untargeted metabolomics.

Agaricus subrufescens has emerged as an important culinary-medicinal mushroom over the last decades. Efforts have been dedicated to upgrade the A. subrufescens productive process via strain selection and cultivation scaling-up. However, little is known on the influence of those variables on the metabolite profiles and nutraceutical properties of this mushroom. In this work, the effects of outdoor versus indoor cultivation on the metabolite profiles of five commercial strains of A. subrufescens were investigated by untargeted metabolomics. UHPLC-MS coupled to multivariate data analysis revealed that the concentration of several metabolites with reported health-related properties as well as related to taste and browning varied significantly between strains and were affected by the cultivation system in a strain-dependent manner. Data suggest that increasing the production scale by means of indoor cultivation may decrease the nutraceutical quality of some A. subrufescens strains while also affecting taste and browning susceptibility to different extents.

Effects of cadmium stress on physiological indexes and fruiting body nutritions of Agaricus brasiliensis.

In this study, 0, 0.5, 1, 1.5, 2, 4, 6 and 8 mg·kg-1 of cadmium were added to the cultivation materials. In order to study the effects of different concentrations of Cd stress on J1 and J77, the contents of antioxidant enzymes, proline and malondialdehyde, Cd content, agronomic traits and yield of fruiting bodies of Agaricus brasiliensis were determined, and the nutritional components such as polysaccharide, triterpene, protein, total sugar and total amino acid were determined. The results showed that the physiological indexes of strain J1 and J77 changed regularly under different concentrations of Cd stress. J1 was a high absorption and low tolerance variety, while J77 was a low absorption and high tolerance variety. Low concentration of Cd promoted the growth of strain J1, and higher concentration of Cd promoted the growth of strain J77. The contents of protein and total amino acids in the two strains changed greatly, followed by polysaccharides, which indicated that Cd stress had the greatest impact on the three nutrients, and other nutrients were not sensitive to Cd stress.

Semisolid culture medium improves mycelial recovery of Agaricus subrufescens cryopreserved in cereal grains.

This study aimed to evaluate the effects of the solid and semisolid culture medium on the mycelial viability of A. subrufescens after 5-year cryopreservation at - 70 °C. Mycelia were grown in three types of whole or ground grains, with or without 5% glycerol addition in the substrate and/or in a cryotube. After 5 years of cryopreservation at - 70 °C, every treatment was thawed and recovered in malt extract culture medium with 15 (solid culture medium) or 5 g L-1 (semisolid culture medium) of agar. The semisolid recovery culture medium increased the mycelial viability recovery capacity of A. subrufescens cryopreserved for 5 years in grains with glycerol only in the cryotube, and specifically with medium-hard wheat grain without glycerol addition at all. Agar-based substrates such as malt extract agar, agar-ground grain, or the one with glycerol addition to the substrate were not effective to keep the mycelial viability, regardless of the recovery culture medium consistency. Hard and medium-hard endosperm wheat grains or hard endosperm rye grains with addition of glycerol as cryoprotectant only to the cryotube were effective to cryopreserve the fungus for 5 years without cryoprotectant addition in the substrate.

Cryopreservation at -75 °C of Agaricus subrufescens on wheat grains with sucrose

Abstract Agaricus subrufescens is a basidiomycete which is studied because of its medicinal and gastronomic importance; however, less attention has been paid to its preservation. This study aimed to evaluate the effect of sucrose addition to substrate and cryotube on the viability of Agaricus subrufescens cryopreserved at -20 °C and at -75 °C for one and two years. Zero, 10% or 20% sucrose was added to potato dextrose agar or wheat grain. The mycelia were cryopreserved in the absence of cryoprotectant or with sucrose solutions at 15%, 30% or 45%. After one or two years at -75 °C or at -20 °C, mycelia were thawed and evaluated about viability, initial time of growth, colony diameter and genomic stability. Cryopreservation at -20 °C is not effective to keep mycelial viability of this fungus. Cryopreservation at -75 °C is effective when sucrose is used in substrates and/or cryotubes. Without sucrose, cryopreservation at -75 °C is effective only when wheat grains are used. Physiological characteristic as mycelial colony diameter is negatively affected when potato dextrose agar is used and unaffected when wheat grain is used after two-year cryopreservation at -75 °C. The fungus genome does not show alteration after two-year cryopreservation at -75 °C.

Cryopreservation at -75°C of Agaricus subrufescens on wheat grains with sucrose.

Agaricus subrufescens is a basidiomycete which is studied because of its medicinal and gastronomic importance; however, less attention has been paid to its preservation. This study aimed to evaluate the effect of sucrose addition to substrate and cryotube on the viability of Agaricus subrufescens cryopreserved at -20°C and at -75°C for one and two years. Zero, 10% or 20% sucrose was added to potato dextrose agar or wheat grain. The mycelia were cryopreserved in the absence of cryoprotectant or with sucrose solutions at 15%, 30% or 45%. After one or two years at -75°C or at -20°C, mycelia were thawed and evaluated about viability, initial time of growth, colony diameter and genomic stability. Cryopreservation at -20°C is not effective to keep mycelial viability of this fungus. Cryopreservation at -75°C is effective when sucrose is used in substrates and/or cryotubes. Without sucrose, cryopreservation at -75°C is effective only when wheat grains are used. Physiological characteristic as mycelial colony diameter is negatively affected when potato dextrose agar is used and unaffected when wheat grain is used after two-year cryopreservation at -75°C. The fungus genome does not show alteration after two-year cryopreservation at -75°C.

First study of hormesis effect on mushroom cultivation.

The use of fungicides is common in mushroom cultivation, but no study was carried out applying reduced doses of fungicides in order to increase yield, taking account the hormesis effect. The aim of this manuscript was to verify the effects of different concentrations of fungicides to stimulate the productivity of different strains of Agaricus bisporus. Two stages were developed, an in vitro study to define the best concentration to be applied in the second experiment an agronomic study, which consisted of the application of the selected fungicides, in their respective concentrations, in an experiment carried out in the mushroom chamber. Clearly, the result of the hormesis effect on mushroom cultivation can be verified. The results obtained in the 1st stage of the study (in vitro) were not always reproduced in the 2nd stage of the study (in vivo). The kresoxim methyl active ingredient may be an important chemical agent, while strain ABI 15/01 may be an extremely important biological agent to increase yield in the study of hormesis effects.

Mycochemical Characterization of Agaricus subrufescens considering Their Morphological and Physiological Stage of Maturity on the Traceability Process.

Agaricus subrufescens Peck is a basidiomycete with immunomodulatory compounds and antitumor activities. This research evaluated the mycochemical composition of A. subrufescens, considering their morphological and physiological stage of maturity, with a particular focus on the development of a traceability process for the formulation of new nutritional products based on fungal foods. The stipes contained a high amount of dry matter (10.33%), total carbohydrate (69.56%), available carbohydrate (63.89%), and energy value (363.97 kcal 100 g-1 DM). The pilei contained a high amount of moisture (90.66%), nitrogen (7.75%), protein (33.96%), ash (8.24), crude fat (2.44%), acid detergent fiber (16.75 g kg-1), neutral detergent fiber (41.82 g kg-1), hemicellulose (25.07 g kg-1), and lignin (9.77 g kg-1). Stipes with mature physiological stage had higher values of dry matter (10.50%), crude fiber (5.94%), total carbohydrate (72.82%), AC (66.88%), and energy value (364.91 kcal 100 g-1 DM). Pilei of the mushrooms in the immature physiological stage had higher values of P (36.83%), N (8.41%), and A (8.44%). Due to the differences between the mycochemical compositions of the morphological parts of mushrooms linked to their physiological stage of maturity, such characteristics have immense potential to be considered for a traceability process. This study can be used for the purpose of providing the consumer with more product diversity, optimizing bioactivities of composts, and allowing farmers an efficient and profitable use of the mushroom biomass.

Preserving and Maintaining Culinary-Medicinal Royal Sun Mushroom, Agaricus brasiliensis (Agaricomycetes), in Sterile Distilled Water.

Strains of Agaricus brasiliensis require special procedures for conservation. Thus, the objective of this research was to establish conservation and maintenance procedures A. brasiliensis strain PSWC838 from the University of Pennsylvania (ABWC838) and an A. brasiliensis strain from the Fujian Agriculture and Forestry University (ABC). The medium in which mycelia grew the quickest for both strains was selected using a multifactorial design with 2 strains, 4 culture media, and incubation for 5 different times; the growth rate (mm/day) was the response variable. Analysis of variance showed that the potato dextrose agar (PDA) medium and potato extract did not display a significantly different growth rate, and PDA was selected for safety reasons. We also evaluated the viability of the strains grown on PDA and 0.2% activated carbon after 3 months of storage in sterile distilled water. A factorial design was applied with 2 factors, the strain and incubation for 10 different times. The Tukey post hoc test indicated that ABC showed quicker and more homogeneous growth than ABWC838. Finally, the results showed that pieces of mycelium of ABC and ABWC838 strains inoculated on the PDA medium with 0.2% activated carbon and preserved in sterile distilled water at 18 ± 1°C showed 100% viability after 3 months of storage. Moreover, the results of semiquantitative biochemical tests confirmed that the production of laccases and amylases was preserved in these strains after storage in sterile water, enhancing their ability to degrade substrates containing lignin and starchy waste.

Agaricus subrufescens: substratum nitrogen concentration and mycelial extraction method on antitumor activity.

Antitumor activity of Agaricus subrufescens has been shown on vegetative mycelium and basidiocarp. However, few studies have assessed the effect of A. subrufescens cultivation conditions and extraction methods on antitumor activity. This study evaluated the effect of nitrogen concentration on the cultivation medium of A. subrufescens and the extraction method of mycelial antineoplastic actives against sarcoma 180 cells implanted in mice. Two nitrogen sources (isolated soybean protein and NaNO3) and 10 nitrogen concentrations (0.25 to 8.0 g/L) were used. Dried mycelium extract was obtained by hot water infusion (1:10 mass:volume; 90 °C) or by aqueous mixture (1:10 mass:volume, ambient temperature) in ultrapure water. The doses were administered daily by gavage to mice implanted with sarcoma 180 cells. Isolated soy protein is more efficient to mycelial biomass production than NaNO3. The mycelial biomass production increases when the cultivation medium is added with high nitrogen concentrations as well as the splenic index and the antitumor activity of the moistened mycelial powder. Hot water extract is more effective than the moistened mycelial powder to reduce tumor. The antitumor activity of hot water mycelial extract is similar to the one of basidiocarps, presenting lower metabolic demand on the spleen, keeping blood parameters normal and promoting animal wellness.

The Effect of the Medicinal Mushrooms Agaricus brasiliensis and Ganoderma lucidum (Higher Basidiomycetes) on the Erythron System in Normal and Streptozotocin-Induced Diabetic Rats.

Diabetes mellitus (DM) is accompanied by the development of hypoxia, which disturbs the physicochemical properties of the erythrocyte membrane and further leads to the occurrence of anemia and a reduction of the lifespan. In response, the body activates compensatory reactions directed at a renewal of the red blood cell pool and an increase in tissue oxygenation. In this study the influence of Agaricus brasiliensis and Ganoderma lucidum medicinal mushroom mycelia on the erythron system of control and streptozotocin (STZ)-induced diabetic rats were investigated. Wistar outbred white male rats were intraperitoneally injected with saline (control rats) or STZ (50 mg/kg, DM rats) and orally treated with placebo or submerged culture mycelium powder (1 g/kg/day) for 2 weeks. Peripheral blood erythrocytes were collected. Hypoglycemic effects of A. brasiliensis and G. lucidum occurred in the diabetic rats, as evidenced by decreased blood glucose and glycosylated hemoglobin concentrations. In STZ-diabetic animals treated with submerged culture mycelium powder, an increase in the number of erythrocytes in the bloodstream (an antianemic effect), erythrocyte resistance to acid hemolysis, and the normalization of fetal hemoglobin concentrations, along with the intensification of erythropoiesis were observed. In conclusion, our results suggest that in diabetic animals A. brasiliensis and G. lucidum have therapeutic effects that manifest in hypoglycemic and antianemic action.

The Effects of Light Intensity, Casing Layers, and Layering Styles on Royal Sun Medicinal Mushroom, Agaricus brasiliensis (Higher Basidiomycetes) Cultivation in Turkey.

The aim of this research is to evaluate the effects of light intensity, casing layers, and layering styles on the production of the culinary-medicinal mushroom Agaricus brasiliensis in Turkey. The experiments were designed in split-split plots and replicated twice. Three different light intensities-I1, 350 lux; I2, 450 lux; and I3, 750 lux-were used in main plots as environmental factors. A mixture of 4 different casing layers- peat (100%), peat-perlite (75%:25%), peat-clinoptilolite (75%:25%), and peat-perlite-clinoptilolite (60%:20%:20%)-were used at split plots and at split plots. S1, a flat, 3-cm casing layer; S2, a flat, 5-cm casing layer; and S3, casing soil ridges 10 cm wide × 4 cm high, 10 cm apart, were deposited on top of 1-cm overall soil casing layers. At the end of the harvest phase, the total yield was estimated per 100 kg of substrate. Biological efficiency (percentage) was determined from the fresh weight of the mushrooms and the dry weight of the compost at the end of the harvesting period. The highest total yield (7.2 kg/100 kg compost) and biological efficiency (27.63%) were achieved from I2 × peat-perlite-clinoptilolite × S2 treatment. Influence of light intensity, casing layer, layering style, and their interaction in treatments with color values (L*, a*, b*, chroma*, and hue*) also were examined. It has been shown that within color values, chroma* (saturation) values of mushroom caps were affected by light intensity, casing layer, and layering style treatments and light intensity × casing layer treatments and the brightness of mushroom caps tended to increase as light intensity increased.

Selected wild strains of Agaricus bisporus produce high yields of mushrooms at 25°C.

BACKGROUND: To cultivate the button mushroom Agaricus bisporus in warm countries or during summer in temperate countries, while saving energy, is a challenge that could be addressed by using the biological diversity of the species. AIMS: The objective was to evaluate the yield potential of eight wild strains previously selected in small scale experiments for their ability to produce mature fruiting bodies at 25°C and above. METHODS: Culture units of 8 kg of compost were used. The yield expressed as weight or number per surface unit and earliness of fruiting were recorded during cultivation in climatic rooms at 17, 25 or 30°C. RESULTS: Only strains of A. bisporus var. burnettii were able to fruit at 30°C. At 25°C they produced the highest yields (27 kg m(-2)) and had best earliness. The yields at 25°C for the strains of A. bisporus var. bisporus ranged from 12 to 16 kg m(-2). The yield ratios 25°C/17°C ranged from 0.8 to 1.2. CONCLUSIONS: The variety burnettii originated in the Sonoran Desert in California showed adaptation for quickly producing fruiting bodies at high temperature when humidity conditions were favorable. Strains of the variety bisporus showed interesting potentials for their ability to produce mature fruiting bodies at higher temperature than present cultivars and might be used in breeding programs.

Analysis of thermophilic fungal populations during phase II of composting for the cultivation of Agaricus subrufescens.

The composition and genetic diversity of fungal populations during phase II of compost production for the cultivation of Agaricus subrufescens was determined using culture-dependent and -independent methods on days 3, 6, 10, 12, and 14 of phase II composting. The isolates were morphologically characterized and subsequently analyzed using repetitive extragenic palindromic sequences (rep-PCR), and the intergenic region was sequenced to genetically identify the isolates. Changes on in the filamentous fungi population were analyzed using denaturing gradient gel electrophoresis (DGGE), and the resulting bands were sequenced. The population did not significantly change from day 3 to 10 (2.55 x 10(5) -6 x 10(5) CFU g(-1)), and maximum counts on day 14 of phase II composting (6.92 log CFU g(-1)). In the morphological characterization, Scytalidium thermophilum, Thermomyces lanuginosus, and Thermomyces ibadanensis were the most abundant identified species. The 26 most abundant isolates identified by morphological analysis were characterized using rep-PCR. A significant amount of genetic diversity was detected among the isolates of all three studied species. Based on the DGGE analysis, the diversity of the fungi was reduced during phase II composting, and S. thermophilum was the predominant species identified throughout the entire process. Thus, this study presents the first report of the involvement of T. ibadanensis in the production of compost for Agaricus mushroom cultivation.

[Adaptability of Brazilian strains of Agaricus subrufescens Peck to fruiting on various casing materials in commercial crops]. / Adaptabilidad de cepas brasileñas de Agaricus subrufescens Peck a la fructificación sobre diferentes capas de cobertura en cultivo comercial.

BACKGROUND: Agaricus subrufescens Peck is a mushroom whose cultivation has aroused great interest worldwide in recent years, and is becoming increasingly popular. A rapid expansion of culture throughout the world is foreseen because of its medicinal and culinary properties. AIMS: This work assesses the effect of 5 different casing layers on the production of 3 strains of Agaricus subrufescens. METHODS: A growth cycle of Agaricus subrufescens under controlled conditions has been carried out. The main production parameters were evaluated. RESULTS: The best results were provided by the ABL 99/30 strain. Peat-based casings have a better yield than those based on mineral soil. The highest yield (6.75kg/m(2), biological efficiency 27.57kg/dt) was provided by the combination ABL 99/30-Euroveen. CONCLUSIONS: Our results suggest that the combination of the strain ABL 99/30 using a peat-based casing layer (Euroveen) offers a high potential for use on a commercial scale by the edible mushroom production sector. The availability of alternatives to the usually cultivated species can make better use of resources, and increase the profitability of this activity.

Optimization of the cultivation conditions for mushroom production with European wild strains of Agaricus subrufescens and Brazilian cultivars.

BACKGROUND: The almond mushroom Agaricus subrufescens (formerly Agaricus blazei or Agaricus brasiliensis) is cultivated at commercial level in Brazil and some Asian countries on local substrates and casing mixtures. Despite its tropical origin, A. subrufescens might be a seasonal option for mushroom growers in western countries, where some wild strains have been isolated. For this purpose, cultivation conditions were developed starting from the substrate and casing mixture commonly used for commercial production of the button mushroom Agaricus bisporus in France. RESULTS: The commercial compost, based on wheat straw and horse manure, used for A. bisporus and the casing mixture (peat and limestone) supplemented with fine sand proved efficient to grow A. subrufescens. Increasing the depth of the casing layer improved significantly the yield and time to fruiting. Daily variations in temperature did not markedly modify the yield. Significantly higher mushroom biomass was obtained with three wild European strains compared with three Brazilian cultivars. The very productive wild strain CA438-A gave mushrooms of size and dry matter content comparable to those of a cultivar. CONCLUSION: Commercial production of A. subrufescens can be developed in western countries on the wheat straw-based substrate commonly used for A. bisporus in these regions, by a simple modification of the casing mixture and maintaining the incubation temperature throughout the crop, which is expected to save energy during summer. Good yields were obtained cultivating European strains under optimised parameters.

Effect of cultivation practices on the ß-glucan content of Agaricus subrufescens basidiocarps.

The present work aimed to assess the effect of the following treatments on the medicinal potential (ß-glucan content) and agronomical performance (yield) of Agaricus subrufescens: five different fungal strains, three cultivation substrates (compost), four casing layers, and four cultivation environments. Two experiments were performed, and the results indicate that the greatest contribution to the variation in ß-glucan content was the strain (35.8%), followed by the casing layer (34.5%), the cultivation environment (15.7%), and the type of compost (9.9%). On the other hand the variation in yield was affected most by the cultivation environment (82.1%), followed by the strain (81.3%), casing layer (49.1%), and compost type (15.2%). These findings underscore the importance of developing a production protocol that employs specific cultivation practices for improving mushroom yield as well as ß-glucan content.

Dynamics of the chemical composition and productivity of composts for the cultivation of Agaricus bisporus strains

Two compost formulations based on oat straw (Avena sativa) and brachiaria (Brachiaria sp.) were tested for the cultivation of three Agaricus bisporus strains (ABI-07/06, ABI-05/03, and PB-1). The experimental design was a 2 x 3 factorial scheme (composts x strains) with 6 treatments and 8 repetitions (boxes containing 12 kg of compost). The chemical characterization of the compost (humidity, organic matter, carbon, nitrogen, pH, raw protein, ethereal extract, fibers, ash, cellulose, hemicellulose, and lignin) before and after the cultivation of A. bisporus and the production (basidiomata mass, productivity, and biological efficiency) were evaluated. Data were submitted to variance analysis, and averages were compared by means of the Tukey's test. According to the results obtained, the chemical and production characteristics showed that the best performances for the cultivation of A. bisporus were presented by the compost based on oat and the strain ABI-07/06.

Physiologic response of Agaricus subrufescens using different casing materials and practices applied in the cultivation of Agaricus bisporus.

Casing materials and practices used in the cultivation of Agaricus bisporus were evaluated in the cultivation of Agaricus subrufescens, using the best techniques for optimization of production, including the possibility of re-casing of the compost for the production of a second crop of mushroom. Casing based on peat moss, loam soil or coir was compared to casing material mixed with or without spawn-run compost. Based on the results, we conclude that the casing layer used in the cultivation of A. subrufescens should not necessarily be the same as that used in the cultivation of A. bisporus. For the tested strain cultivated with loam soil as casing layer, the ruffling technique is highly superior to CACing and should be pursued in further research. The re-casing of compost in new cycles showed good results suggesting that the currently used compost could be improved.

Potential of European wild strains of Agaricus subrufescens for productivity and quality on wheat straw based compost.

The Brazilian almond mushroom is currently cultivated for its medicinal properties but cultivars are suspected all to have a common origin. The objective of this work was to assess the potential of wild isolates of Agaricus subrufescens Peck (Agaricus blazei, Agaricus brasiliensis) as a source of new traits to improve the mushroom yield and quality for developing new cultures under European growing conditions. The wild European strains analysed showed a good ability to be commercially cultivated on wheat straw and horse manure based compost: shorter time to fruiting, higher yield, similar antioxidant activities when compared to cultivars. They have a valuable potential of genetic and phenotypic diversity and proved to be interfertile with the original culture of the Brazilian almond mushroom. Intercontinental hybrids could be obtained and combine properties from both Brazilian and European germplasm for increasing the choice of strains cultivated by the mushroom growers.

Dynamics of the chemical composition and productivity of composts for the cultivation of Agaricus bisporus strains.

Two compost formulations based on oat straw (Avena sativa) and brachiaria (Brachiaria sp.) were tested for the cultivation of three Agaricus bisporus strains (ABI-07/06, ABI-05/03, and PB-1). The experimental design was a 2 × 3 factorial scheme (composts × strains) with 6 treatments and 8 repetitions (boxes containing 12 kg of compost). The chemical characterization of the compost (humidity, organic matter, carbon, nitrogen, pH, raw protein, ethereal extract, fibers, ash, cellulose, hemicellulose, and lignin) before and after the cultivation of A. bisporus and the production (basidiomata mass, productivity, and biological efficiency) were evaluated. Data were submitted to variance analysis, and averages were compared by means of the Tukey's test. According to the results obtained, the chemical and production characteristics showed that the best performances for the cultivation of A. bisporus were presented by the compost based on oat and the strain ABI-07/06.