A cascade approach to sustainable agriculture: From mushroom mycelium to lettuce harvest.

Sustainable agriculture involves adopting best practices in food production to promote environmental and economic sustainability. Its implementation primarily aims to utilise organic residues to increase yield, diversify production, and reduce costs. In this context, the objective of this study was to investigate different substrates for Hypsizygus ulmarius production and, from its residual substrate, to develop formulations for lettuce seedling growth and subsequent greenhouse cultivation. For mushroom production, substrates were prepared from sawdust with the addition of wheat bran, rice bran, soybean meal, and calcite, resulting in four distinct substrate formulations. The spent mushroom substrate (SMS), obtained at the end of cultivation, was used for lettuce seedling production along with the commercial substrate Carolina Soil® and the soil conditioner BacSol®. The top five formulations were selected for transplanting in the greenhouse. Regarding mushroom production, substrates with higher carbon/nitrogen ratios, around 66: 1, resulted in higher yields. For seedling production, SMS showed lower efficiency compared to the commercial substrate Carolina Soil®, which also benefited from the addition of the soil conditioner BacSol®. However, after transplanting lettuce seedlings, the formulation containing SMS showed superior results in almost all evaluated parameters. Therefore, we concluded that despite the inefficiency of using H.ulmarius SMS for lettuce seedling production, it favours the establishment of seedlings in greenhouse cultivation environments.

Bioconversion of rice straw by Lentinula edodes under different spawn formulations.

To attend to the growing world demand for mushrooms, it is interesting to increase the system's productivity, improve quality and reduce production costs. This study aimed to optimize the production and quality of fruiting bodies of the edible and medicinal mushroom Lentinula edodes (shiitake), in agroresidues substrate using appropriate strain and spawn formulation. The evaluation was conducted using two strains under seven different spawn formulations (Control [C]: Sorghum grain + 2.5% CaCO3; (2) C + 2.5% sawdust; (T3) C + 5% sawdust; (T4) C + 2.5% peat; (T5) C + 5% peat; (T6) C + 1.25% sawdust + 1.25% peat; (T7) C + 2.5% sawdust + 2.5% peat) that were inoculated into the blocks at a proportion of 2% (w/w). The substrate was formulated with 63% rice straw, 20% sawdust, 15% wheat bran, and 2% CaCO3 and sterilized. The incubation period was 87 days. Two flushes were obtained. Adding small aliquots of peat and sawdust to the inoculum gave significantly higher morphological results than the control in all variables analyzed. The days required for the first harvest ranged from 87 to 94 days. The average weight of basidiomes ranged from 6.38 to 28.75 g. The productivity data show superior results for the treatments in which the spawn was supplemented with sawdust and peat. Enhanced bioconversion with supplemented spawn shows promises for yield and composition improvement, crucial for commercial viability. It can be concluded that shiitake production using agroresidues such as straw can be increased using a suitable strain/spawn for optimal production.

Decoding the chromosome-scale genome of the nutrient-rich Agaricus subrufescens: a resource for fungal biology and biotechnology.

Agaricus subrufescens, also known as the "sun mushroom," has significant nutritional and medicinal value. However, its short shelf life due to the browning process results in post-harvest losses unless it's quickly dehydrated. This restricts its availability to consumers in the form of capsules. A genome sequence of A. subrufescens may lead to new cultivation alternatives or the application of gene editing strategies to delay the browning process. We assembled a chromosome-scale genome using a hybrid approach combining Illumina and Nanopore sequencing. The genome was assembled into 13 chromosomes and 31 unplaced scaffolds, totaling 44.5 Mb with 96.5% completeness and 47.24% GC content. 14,332 protein-coding genes were identified, with 64.6% of the genome covered by genes and 23.41% transposable elements. The mitogenome was circularized and encoded fourteen typical mitochondrial genes. Four polyphenol oxidase (PPO) genes and the Mating-type locus were identified. Phylogenomic analysis supports the placement of A. subrufescens in the Agaricomycetes clade. This is the first available genome sequence of a strain of the "sun mushroom." Results are available through a Genome Browser (https://plantgenomics.ncc.unesp.br/gen.php?id=Asub) and can support further fungal biological and genomic studies.

A Comparative Analysis of Biodegradation and Bioconversion of Lentinula edodes and Other Exotic Mushrooms.

Mushrooms are capable of bioconverting organic residues into food. Understanding the relationship between high-quality yields and substrate biomass from these residues is critical for mushroom farms when choosing new strains. The objective of this exploratory study was, therefore, to analyze whether exotic mushrooms, namely, Pleurotus eryngii, Flammulina velutipes, and Agrocybe aegerita, could biologically convert the substrate into edible mushrooms as effectively as Lentinula edodes (baseline). Five experiments were carried out. Biological efficiency, biodegradability coefficient, mass balance and chemical characterization of the substrate were evaluated. Strategically hydrating the sawdust enabled L. edodes to achieve the greatest biodegradability and biological efficiency of 0.5 and 94.2 kg dt-1, respectively. The values for L. edodes on wheat straw without hydration were 0.2 and 68.8 kg dt-1, respectively. From 1000 kg of fresh substrate, P. eryngii produced 150.1 kg of edible mushrooms, making it technically competitive with L. edodes on wheat straw (195.9 kg). Hence, P. eryngii was the most reliable option for scaling among the exotic mushrooms. The analytical insights from our study provide further knowledge to advance the field's prominence in high-throughput mushroom-producing systems, particularly for exotic mushrooms.

Metaprofiling of the Bacterial Community in Colonized Compost Extracts by Agaricus subrufescens.

It is well-known that bacteria and fungi play important roles in the relationships between mycelium growth and the formation of fruiting bodies. The sun mushroom, Agaricus subrufescens, was discovered in Brazil ca. 1960 and it has become known worldwide due to its medicinal and nutritional properties. This work evaluated the bacterial community present in mushroom-colonized compost extract (MCCE) prepared from cultivation of A. subrufescens, its dynamics with two different soaking times and the influence of the application of those extracts on the casing layer of a new compost block for A. subrufescens cultivation. MCCEs were prepared through initial submersion of the colonized compost for 1 h or 24 h in water followed by application on casing under semi-controlled conditions. Full-length 16S rRNA genes of 1 h and 24 h soaked MCCE were amplified and sequenced using nanopore technology. Proteobacteria, followed by Firmicutes and Planctomycetes, were found to be the most abundant phyla in both the 1 h and 24 h soaked MCCE. A total of 275 different bacterial species were classified from 1 h soaked MCCE samples and 166 species from 24 h soaked MCCE, indicating a decrease in the bacterial diversity with longer soaking time during the preparation of MCCE. The application of 24 h soaked MCCE provided increases of 25% in biological efficiency, 16% in precociousness, 53% in the number of mushrooms and 40% in mushroom weight compared to control. Further investigation is required to determine strategies to enhance the yield and quality of the agronomic traits in commercial mushroom cultivation.

Biochemical Approaches on Commercial Strains of Agaricus subrufescens Growing under Two Environmental Cultivation Conditions.

In the present work, the effect of the cultivation process, in the field and under a controlled environment, on biochemical parameters by using commercial strains of A. subrufescens were evaluated. The results obtained revealed that the strains cultivated in the field presented higher levels for most of the parameters evaluated (organic acids (20.5-48.0 g/100 g dw), tocopherols (107.0-198.6 µg/100 g dw), and phenolic acids and related compounds (245.2-359.0 µg/100 g dw and 10.6-23.7 µg/100 g dw, respectively)), except for the carbohydrates (53.4-72.6 g/100 g dw), energetic value (373-380 Kcal/100 g dw), and total free sugars (28.8-43.1 g/100 g dw), parameters in which the strains grown in a controlled environment present better results. For both cultivation systems, similar results were obtained regarding saturated, monounsaturated, and polyunsaturated fatty acids, as well as antioxidant and antimicrobial activities. These data contribute to the knowledge and highlight the characterized strains and the cultivation process, which can be used to obtain ingredients with potential applicability as a source of functional compounds.

Dereplication of extracts from nutraceutical mushrooms Pleurotus using molecular network approach.

Pleurotus is an edible mushroom from the well-known genus of Basidiomycetes; it is the second-most commonly consumed mushroom worldwide. This genus is characterized by the presence of steroids, fatty acids, and polysaccharides. Recently, Pleurotus has become popular as a functional food owing to its health benefits, primarily because they are a source of vitamins, fibers, minerals, and lipids. In natural products chemistry, dereplication techniques identify bioactive molecules from natural sources such as plants and fungi without isolating or characterizing molecules. We used dereplication techniques aided by the Global Natural Products Social Molecular Network to analyze the chemical composition of the methanolic extracts of six Pleurotus species (P. sapidus, P. ostreaus, P. ostreaus var. Florida, P. djamor, P. citrinopileatus, and P. pulmonarius), to identify bioactive molecules with nutraceutical properties. Using this technique, we identified several molecular families, including eight fatty acids and seven steroids. Our findings suggest that dereplication is a relatively rapid tool for characterizing fungal species and determining their nutraceutical value.

Influence of strains and environmental cultivation conditions on the bioconversion of ergosterol and vitamin D2 in the sun mushroom.

BACKGROUND: The fungus Agaricus subrufescens is grown commercially in China, the USA, Brazil, Taiwan and Japan, among others. However, each country adopts a cultivation system that significantly influences the agronomical parameters and chemical composition of the harvested mushrooms. In this study, the influence of the cultivation process on the content of ergosterol and vitamin D2 was evaluated. RESULTS: Four commercial strains of A. subrufescens (ABL 04/49, ABL CS7, ABL 18/01 and ABL 19/01) and two environmental cultivation conditions (in the field and a controlled chamber with the absence of sunlight) were used. Infield cultivation, ABL CS7 and ABL 19/01 strains presented better agronomic parameters, whereas in a protected environment ABL 19/01, ABL 04/49 and ABL 18/01 demonstrated better performance, respectively. The highest biological efficiency value (64%) was provided by ABL 19/01 strain in a controlled environment. CONCLUSION: The highest content in ergosterol (990 mg kg-1 ) and vitamin D2 (36.8 mg kg-1 ) were observed in mushrooms obtained in the field from strain ABL 04/49, which presents reasonable agronomic parameters for cultivation. © 2021 Society of Chemical Industry.

Spent mushroom substrate is capable of physisorption-chemisorption of CO2.

No in-depth investigation exists on the feasibility of integrating hydrothermal carbonization (HTC) and pelletization into the process of making spent mushroom substrate (SMS), an agro-food residue from the commercial mushroom industry, into an adsorbent for post-combustion CO2 removal. Therefore, this study analyzed if it could be possible for systematically converting low-pressure hydrochars of various SMSs into carbon-adsorbing mini-capsules. Sources of SMS included paddy straw and achiote capsule shell from Pleurotus ostreatus; eucalyptus sawdust and grassy straw from Lentinula edodes; and compost containing peat or soil as casing layer from Agaricus subrufescens. The eucalyptus sawdust and grassy straw from L. edodes outperformed the other biomaterials in adsorbing CO2, and thus effectively encapsuled most of the gas, 8.25 mmol g-1 and 8.10 mmol g-1, respectively. They contained mostly hetero-atoms of O and N, requiring less unit energy to bind acidic molecules of CO2 at the alkaline sites. The amount of unit energy the pore-filling process demanded at 25 °C was 12.65 kJ mol-1, an attribute of self-sustaining and saleable physisorption. A negative 6.80 kJ mol-1 free energy validated both spontaneity and exothermal of biocarbons at steady-state atmosphere. The major findings and innovations of our study support utilizing SMS as an adsorbent as a carbon capture, storage and utilization networking. Our insights into the physisorption-chemisorption on SMS are timely and relevant to help manage the re-use of SMS, and thus bring the global mushroom industry closer to environmental sustainability and toward a lower carbon society and circular economy.

Tecnologic Development on Pleurotus Cultivation: Specific Practices Used in Brazil

HIGHLIGHTS P. ostreatus and P. sapidus are the most productive species under the evaluated conditions. Different growing systems are suitable for the production of P. ostreatus var. Florida. Temperature control level affects differently the P. ostreatus var. Florida isolates. Environmental and strain factors affect yield and production parameters of P. ostreatus var. Florida.

Abstract In Brazil, Pleurotus is the most important mushroom produced especially P. ostreatus var. Florida. In this country as in many others, the great potential for mushroom cultivation remains unexplored. Therefore, it is very important to develop new studies that allow optimizing its production. The aims of the manuscript were: i) to evaluate the productivity of six different species of Pleurotus (P. citrinopileatus; P. djamor; P. ostreatus; P. ostreatus var. Florida; P. pulmonarius; P. sapidus); ii) to measure the effect of three different environmental conditions during cultivation of three isolates of P. ostreatus var. Florida. As results, P. ostreatus and P. sapidus were the most productive isolates under the evaluated conditions. Different environments produced variable effects according to the P. ostreatus var. Florida isolates, being possible to observe a highly plastic strain (POF 02/18), a highly sensitive strain (POF 03/18) and a strain with variable responses (POF 01/18).

Influence of Calcium Silicate on the Chemical Properties of Pleurotus ostreatus var. florida (Jacq.) P. Kumm.

Supplementation of mushroom substrates has been linked to a higher resistance against insect pests, although few studies show the impact of this supplementation on the different agronomical parameters of mushrooms or even their chemical composition. In this work, the variation in the biological and chemical composition of oyster mushroom (Pleurotus ostreatus var. florida (Jacq.) P. Kumm) was analysed after varying the substrate supplementation of calcium silicate (0, 0.5, 1, 2, and 4% (w/w%)) during two harvest flushes. Overall, supplementation did not change the weight, the number of fruiting bodies, biological efficiency, yield ratio, and productivity rate of the mushrooms, although the harvest flushes did show significant differences. Furthermore, slight changes were found in the chemical composition with an increase in vitamin D2 and tocopherols for the mushrooms with higher amounts of calcium silicate. Overall, the substrate supplementation did not seem to induce expressive changes or decrease production yields, and can, therefore, continue to be researched as a potential application to fight agronomical pests.

Optimization of cultivation techniques improves the agronomic behavior of Agaricus subrufescens.

New species of medicinal mushrooms have emerged over the past several decades, such as the Sun mushroom, Agaricus subrufescens. Horticultural improvements are required to shift its cultivation from small-scale local production to large-scale international production. The research reported here evaluated the agronomic behavior and the chemical characteristics of the Sun mushroom as a function of i) nutritional supplementation ii) ruffling of the casing layer and iii) the temperature management on the primordia induction and reduction of the crop cycle. Supplementation was beneficial for yield, unit mushroom weigh and decrease in time to first harvest. Supplementation improved biological efficiency with Champfood providing a yield increase of 15% over the non-supplemented compost. Among the supplements only Promycel increased the individual mushroom weight. Ruffling overall improved the yield in the 2nd and 4th flush. Already biological efficiency was greater by 21%. The highest yield harvested in any single day in the crop occurred in 3rd flush with the amount of 2.484 kg of mushrooms per m2 for the rapid induction method. Still the biological efficiency was not significantly affected by the mushroom induction temperature method. Only the fat content of the mushrooms was positively affected by the rapid induction of primordia. Champfood supplement promotes a reduction in the value of earliness and an increase of 1st flush yield. The ruffling technique provided an increase in biological efficiency due to the great number of mushrooms harvested. Rapid primordia induction allowed the crop cycle to end 3 days earlier than the slow primordia induction, providing a higher production rate.

HS-SPME/GC-MS Assisted Analysis of Volatile Constituents in Different Strains of Shiitake Culinary- Medicinal Mushroom, Lentinus edodes (Agaricomycetes).

The shiitake culinary-medicinal mushroom Lentinus edodes is one of the most consumed species worldwide because it has nutritional, medicinal, and palatable properties. Its organoleptic characteristics contribute substantially to its high popularity. The pleasant aromas result from the presence of volatile compounds. The objective of the present work was to study the profiles of volatile constituents of fresh fruiting bodies of five strains of L. edodes. The volatile compounds were extracted by solid phase microextraction method and analyzed by gas chromatography and mass spectrometry. The aromatic profiles of the strains revealed variability. Both alcohols and sulfides were the most abundant volatile compounds. LE6 strain presented the highest number of volatile compounds with predominance of sulfides (dimethyl pentasulfide, s-tetrathiane) and for LE2, the aldehydes were the most representative chemical class with the main volatile being (E)-2-octen-1-al.

Study of Waste Products as Supplements in the Production and Quality of Pleurotus ostreatus var. Florida.

Among the cultivated mushroom, the genus Pleurotus is the second largest produced worldwide and the most produced in Brazil. The application of agricultural by-products (wastes) as substrate supplement is an effective approach to generate quality food while promoting a circular economy in agriculture. The manuscript evaluates the three key aspects of this practice: (1) the response of different mushroom strains to supplementation, (2) the use of agricultural by-products with different N content, and (3) the efficacy of certain preliminary treatments applied to the supplements. To this end, production and nutritional quality of the mushroom were tested along the crop cycle. Compared to the control substrate, the yield increased by 11, 26, 30 and 42% in the first flush and by 86 and 31% in the second flush. Supplementation resulted in an increment of the fiber and protein content of mushroom and a decline of carbohydrate and lipid content of mushroom.

Use of peanut waste for oyster mushroom substrate supplementation-oyster mushroom and peanut waste.

The aim of the research was to verify the influence of macro and micronutrients present in the peanut waste (hulls and nuts) for supplementation of Pleurotus ostreatus substrate. The raw materials for base substrate preparation were Brachiaria dictyoneura, sugarcane bagasse (bulk material), rice and wheat bran, calcitic limestone, and gypsum. The following supplement formulations were used as treatments: (1) 100% peanut hulls, (2) 80% peanut hulls + 20% nuts, (3) 60% peanut hulls + 40% nuts, (4) 40% peanut hulls + 60% nuts, (5) 20% peanut hulls + 80% nuts, and (6) 100% nuts. A commercial supplement was also used as an additional treatment. The supplementation was done at spawning using the rates of 1% and 2% wet weight of the substrate. Positive correlations amongst yield and N content, and weight of mushroom and P and K content were verified with 1% supplement. A positive correlation between yield and Cu content, and a negative correlation between yield and Mn content were observed with 2% supplement. The use of peanut waste can be used as supplement for the production of P. ostreatus increasing biological efficiency up to 61%. A better combination can be reached with 20% peanut hulls + 80% nuts or 100% nuts. The addition of 2% supplement in the substrate provided greater yield than 1%.

Pleurotus spp. cultivation on Brachiaria sp. straw treatment with alkaline water: Oyster mushroom and substrate treatment.

The aim of this research was to evaluate the efficiency of aqueous alkali-treated Brachiaria straw for the cultivation of appropriate species of oyster mushroom. The substrate used in the cultivation of various Pleurotus spp. was soaked for 20min by using two different procedures: (i) 0.5-2.0% Ca(OH)2 in 100L water, and (ii) 50-250L water. As a result, 1% Ca(OH)2 dissolved in 100L water and 3.5kg of Brachiaria straw presented the best production. The most suitable species for the application of the present method were P. pulmonarius and P. sapidus. The success of this technique is directly related to the concentration of Ca(OH)2 and water, the species, and the origin and quality of raw material used as the substrate in the production of oyster mushroom.

Pleurotus spp. cultivation on Brachiaria sp. straw treatment with alkaline water

Abstract The aim of this research was to evaluate the efficiency of aqueous alkali-treated Brachiaria straw for the cultivation of appropriate species of oyster mushroom. The substrate used in the cultivation of various Pleurotus spp. was soaked for 20 min by using two different procedures: (i) 0.52.0% Ca(OH)2 in 100 L water, and (ii) 50250 L water. As a result, 1% Ca(OH)2 dissolved in 100 L water and 3.5 kg of Brachiaria straw presented the best production. The most suitable species for the application of the present method were P. pulmonarius and P. sapidus. The success of this technique is directly related to the concentration of Ca(OH)2 and water, the species, and the origin and quality of raw material used as the substrate in the production of oyster mushroom.

Pleurotus spp. cultivation on Brachiaria sp. straw treatment with alkaline water

Abstract The aim of this research was to evaluate the efficiency of aqueous alkali-treated Brachiaria straw for the cultivation of appropriate species of oyster mushroom. The substrate used in the cultivation of various Pleurotus spp. was soaked for 20 min by using two different procedures: (i) 0.5-2.0% Ca(OH)2 in 100 L water, and (ii) 50-250 L water. As a result, 1% Ca(OH)2 dissolved in 100 L water and 3.5 kg of Brachiaria straw presented the best production. The most suitable species for the application of the present method were P. pulmonarius and P. sapidus. The success of this technique is directly related to the concentration of Ca(OH)2 and water, the species, and the origin and quality of raw material used as the substrate in the production of oyster mushroom.

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.

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.