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Economic interest in sugarcane bagasse has significantly increased in recent years due to the worldwide demand for sustainable energy production. The use of sugarcane bagasse for holocellulase production has been a strategy for bioconversion of lignocellulosic residues into second-generation ethanol. The fungi secrete to the culture medium a cocktail of enzymes necessary to convert biomass into nutrients. Thus, this study aimed to analyze the production profile of holocellulases from Aspergillus and Humicola species, Trichoderma reesei RP698, and Mycothermus thermophilus grown in sugarcane bagasse, culm of energy cane, and culm of sugarcane SP80-3280. The capacity of the enzymatic pools in the hydrolysis of cell walls of these sugarcane varieties was also verified. M. thermophilus was the best producer of endoglucanase, cellobiohydrolase, β-glucosidase, xylanase, β-xylosidase, xyloglucanase, arabinanase, arabinofuranosidase, mannanase, and acetyl xylan esterase. T. reesei RP698 also produced and secreted a wide range of holocellulases to the medium. The saccharification of sugarcane bagasse, energy cane, and sugarcane SP80-3280 by the enzymatic cocktails obtained from M. thermophilus released 0.87 ± 0.05 mg.mL−1, 0.88 ± 0.07 mg.mL−1, and 1.10 ± 0.08 mg.mL−1 of reducing sugars, respectively. However, the application of T. reesei RP698 extracts showed a release of 0.85 ± 0.03 mg.mL−1, 0.40 ± 0.03 mg.mL−1, and 0.83 ± 0.03 mg.mL−1 of reducing sugars. Therefore, T. reesei RP698 and M. thermophilus showed to be good holocellulase producers, and their crude extracts presented a great capacity for the hydrolysis of the different kinds of sugarcane residues.

Bioactivity is defined as the intrinsic property of compounds that enables their participation in specific biological reactions. This study aimed to evaluate the antimicrobial capacity and to separate and characterize bioactives from aqueous and hydroalcoholic extracts obtained from the mycelium of medicinal mushrooms Pleurotus albidus and Phellinus linteus. Antimicrobial activity, through the disc diffusion method, was found against strains of Bacillus cereus, B. subtilis, Pseudomonas aeruginosa, and Staphylococcus aureus. P. albidus extracts showed better activity against Bacillus strains, whereas Ph. linteus extracts had greater effectiveness against S. aureus and P. aeruginosa. Aqueous extraction was best for obtaining bioactive compounds of P. albidus, whereas 30% hydralcoholic extraction performed best for obtaining Ph. linteus. Mass spectrometry analyses allowed the identification of the main chemical compounds extracted from the fungal biomasses, including glutathione oxidase, leucovorin, and riboflavin. Taking these findings into consideration, P. albidus and Ph. linteus might be used as sources of bioactive molecules for the development of novel drugs or nutraceuticals, contributing to the improvement of public health.

The production of proteases by white rot fungi, such as those of the genus Pleurotus, is related to the degradation of wood proteins, the substrate on which these fungi grow in the environment. From the point of view of production, they are still little explored for this purpose. A selection of agro-industrial residues highlighted corn bagasse as the best substrate for solid-state protease production using the basidiomycete Pleurotus pulmonarius. The enzyme production was maximized through a factorial design, where the enzyme activity increased from 137.8 ± 1.9 to 234.1 ± 2.7 U/mL. Factors such as temperature stability, pH, and chemical reagents were evaluated. The optimum temperature was 45 °C, showing low thermal stability at higher temperatures. The enzyme inhibition occurred by Mn

Laccases (EC. 1.10.3.2) have a broad range of industrial applications. In order to overcome problems associated with loss of activity, storage and reusability of the free enzyme, a laccase from Gan...

Climate change is predicted to cause more extreme events, such as heatwaves, and different precipitation patterns. The effects of warming and short-term drought on soil microbial communities, in particular fungal communities, remain largely unexplored under field conditions. Here, we evaluated how the fungal community of a tropical grassland soil responds to these changes. A field experiment was carried out in a temperature free-air controlled enhancement (T-FACE) facility in Ribeirao Preto, Brazil. The isolated and combined effects of drought and a 2°C increase in temperature were investigated. Based on metabarcoding of the ITS2 region, a total of 771 operational taxonomic units were observed. While warming affected the community structure, drought affected the alpha diversity, and the interaction between warming and drought affected both diversity and structure. The change in community composition driven by warming affected only the less abundant species (>1% of the total sequences). The aspect of the fungal communities that was most affected was diversity, which was increased by drought (p < .05), mostly by reducing the dominance of a single species, as observed in the watered plots. In a phylogenetic context, some fungal taxa were favoured by changes in temperature (Hypocreales) and drought (Sordariales) or disadvantaged by both (Pleosporales). It was of note that a water deficit increased the abundance of phytopathogenic fungi, such as Curvularia, Thielavia and Fusarium species. Overall, our results provide evidence that fungal communities in tropical grassland soils have greater sensitivity to drought than to temperature, which might increase the incidence of certain soil-borne diseases.

The objective of this study was to evaluate the antioxidant activity, determine and quantify the phenolic compounds and other compounds, and evaluate the cellular cytotoxicity of mycelium extracts of two new Basidiomycete mushrooms strains isolated in Brazil and identified as Lepista sordida GMA-05 and Trametes hirsuta GMA-01. Higher amounts of proteins, free amino acids, total and reducing carbohydrates, and phenolic compounds as chlorogenic, ferulic, caffeic, and gallic acids were found in extracts of T. hirsuta and L. sordida. Protocatechuic acid was found only in aqueous extracts of L. sordida. The TLC of the extracts showed the predominance of glucose and smaller amounts of xylose. It was observed through UPLC-MS higher amounts of phenolic compounds. The aqueous extract from T. hirsuta had the most noteworthy results in the antioxidant assays, especially the ABTS test. The cytotoxic activity was evaluated using two different cell lineages and showed higher toxicity for L. sordida in macrophages J774-A1. However, in Vero cells, it was 12.6-fold less toxic when compared to T. hirsuta. Thus, both mushrooms show potential as functional foods or additives, presenting phenolic content, antioxidant activity, and low cytotoxic activity in the tested cells. GRAPHICAL ABSTRACT: [Image: see text]

Mushrooms can be used in culinary applications, as a source of antioxidants, and for many therapeutic purposes. Foods are a natural source of antioxidant compounds, molecules that can inhibit oxidation of other molecules through the removal of free radicals, and thus play an important role in the protection of an organism's health. Phenolic compounds are secondary metabolites widely present in vegetables and mushrooms. Some studies highlight the capacity of mushrooms to produce antioxidant, antimicrobial, and antitumoral substances. This study aimed to evaluate the antioxidant capacity (with the ABTS, Trolox equivalent antioxidant capacity, and ferric reducing antioxidant power methods) and antimicrobial activity (disc diffusion method) of an Lentinula boryana isolate, using its mycelium as the primary material of study. The results showed that L. boryana has benefits such as antioxidant activity in medicinal and culinary uses.

The lignocellulosic biomass comprises three main components: cellulose, hemicellulose, and lignin. Degradation and conversion of these three components are attractive to biotechnology. This study aimed to prospect fungal lignocellulolytic enzymes with potential industrial applications, produced through a temporal analysis using Hymenaea courbaril and Tamarindus indica seeds as carbon sources. α-L-arabinofuranosidase, acetyl xylan esterase, endo-1,5-α-L-arabinanase, β-D-galactosidase, β-D-glucosidase, β-glucanase, β-D-xylosidase, cellobiohydrolase, endoglucanase, lichenase, mannanase, polygalacturonase, endo-1,4-β-xylanase, and xyloglucanase activities were determined. The enzymes were produced for eight filamentous fungi: Aspergillus fumigatus, Trametes hirsuta, Lasiodiplodia sp., two strains of Trichoderma longibrachiatum, Neocosmospora perseae, Fusarium sp. and Thermothelomyces thermophilus. The best producers concerning enzymatic activity were T. thermophilus and T. longibrachiatum. The optimal conditions for enzyme production were the media supplemented with tamarind seeds, under agitation, for 72 h. This analysis was essential to demonstrate that cultivation conditions, static and under agitation, exert strong influences on the production of several enzymes produced by different fungi. The kind of sugarcane, pretreatment used, microorganisms, and carbon sources proved limiting sugar profile factors.

The concern with the environment and the depletion of natural resources has aroused the interest for the rational use and recycling of water. Therefore, this study evaluated the capacity of the Trametes sp. M3 isolate in the bioremediation of Reactive Blue (RB) 268 dye and its potential for use as an adsorbent in the treatment of textile effluents. In a solid medium containing RB 268, the discoloration rate was 1.00 and the growth rate was 1.4 cm/day. When evaluated in the in vivo biodiscoloration process, 100% of the dye lost its color after 120 h. The oxidative enzyme laccase was found in cultures containing the dye with high activity, indicating that it underwent induction. The chromatogram after cultivation of the fungus showed that there was a change in the structure of RB 268. The mycelium of the culture with the dye was analyzed by FTIR, pointing to an adsorption of RB 268 or its metabolites despite the absence of the color. In the biosorption, the best results were obtained when the mycelium was treated with HCl. The toxicity of the medium decreased after the cultivation of the fungus allowing the survival of the microcrustaceans in the acute toxicity bioassay.

Laccases are oxidoreductase enzymes that have the ability to oxidize phenolic substrates. Its biotechnological potential has been greatly explored in many areas as biotechnology industry, bioremediation of dyes, food industry and environmental microbiology. The aim of this study was maximize the laccase production by Pleurotus pulmonarius (Fr.) Quélet in solid-state fermentation (SSF) using orange waste as substrate. After optimization the capability of the crude laccase to decolorize dyes was analyzed. The fermentation medium in the solid-state was optimized by applying a factorial design. After statistics optimization, laccase activity increased two times. The laccase activity appears to be correlated with the ability of crude extract to decolorize some industrial dyes. The optimized laccase was characterized with respect to optimum pH, influence of temperature and salts. Our results demonstrate that P. pulmonarius was an efficient producer of an important industrial enzyme, laccase, in a cheap solid-state system using orange waste as substrate. Laccases are oxidoreductase enzymes that have the ability to oxidize phenolic substrates. Its biotechnological potential has been greatly explored in many areas as biotechnology industry, bioremediation of dyes, food industry and environmental microbiology. The aim of this study was maximize the laccase production by Pleurotus pulmonarius (Fr.) Quélet in solid-state fermentation (SSF) using orange waste as substrate. After optimization the capability of the crude laccase to decolorize dyes was analyzed. The fermentation medium in the solid-state was optimized by applying a factorial design. After statistics optimization, laccase activity increased two times. The laccase activity appears to be correlated with the ability of crude extract to decolorize some industrial dyes. The optimized laccase was characterized with respect to optimum pH, influence of temperature and salts. Our results demonstrate that P. pulmonarius was an efficient producer of an important industrial enzyme, laccase, in a cheap solid-state system using orange waste as substrate.

There are different varieties of mushrooms not yet studied spread all over the planet. The objective of this study was to evaluate biochemical properties and effects on mitochondrial respiration of eight Basidiomycete mushrooms: Flaviporus venustus EF30, Hydnopolyporus fimbriatus EF41 and EF44, Inonotus splitgerberi EF46, Oudemansiella canarii EF72, Perenniporia sp. EF79, Phellinus linteus EF81, and Pleurotus albidus EF84. Total phenols, ABTS, TEAC, FRAP, and ORAC were measured in order to determine the antioxidant capacity. Antimicrobial potential was studied by disc-diffusion and microdilution method. Cytotoxicity was determined in murine peritoneal macrophages. The bioenergetic aspects were evaluated by the uncoupling of the oxidative phosphorylation in mitochondrias. The H. fimbriatus mushroom was the one that presented the most significant results for the antioxidant assays. Three mushrooms presented antimicrobial activity, indicating a potential for formulation of drugs. The results suggest that I. spligerberi has an uncoupling activity, even at the lowest concentration tested, dissipating the mitochondrial electrochemical gradient. On the other hand, P. albidus has effect only on succinate-oxidase activity without influencing mitochondrial respiratory efficiency. Therefore, both interfere negatively in mitochondrial respiration. In relation with the cytotoxicity in peritoneal macrophages, O. canarii and F. venustus were cytotoxic in this type of cells.

The aqueous extracts of mycelium (MAE) and basidioma (BAE) of the mushroom Pleurotus pulmonarius (Fr.) Quel. were compared for their chemical composition, phenolic compounds identified using HPLC and antioxidant activities. The MAE contained 66.1 μg of gallic acid, 27.0 μg of ferulic acid and 217 μg of caffeic acid/g dry weight (dw). In addition, 626 μg of gallic acid, 347 μg of caffeic acid, 53.0 μg of vanillic acid and 25.4 μg of ρ-coumaric acid were found in BAE/g dw. The levels of soluble proteins, soluble carbohydrates and free amino acids were higher in the BAE. The MAE of P. pulmonarius were efficient in chelating ferrous ions (EC50 of 1.81 mg dw/mL). The EC50 for DPPH and ABTS radicals were 0.51 and 0.03 mg dw/mL, respectively, showing high antioxidant capacity. The results of this study showed that mycelium and basidioma of P. pulmonarius have the potential to be used as sources of antioxidant compounds and nutrients.

The study evaluated the production of proteases in solid-state fermentation using wheat bran as a substrate. The best producing isolates were used to obtain crude extract which was evaluated for optimal pH and temperature, thermostability, effect of salts and activity against inhibitors. The studied fungi were Aspergillus sp. 125, Fusarium sp. 132, Fusarium sp. 206, Pleurotus albidus 018 and Pleurotus pulmonarius CCB20. The isolates with better results (Aspergillus sp. and P. albidus), showed protease activity with an optimum pH of 7.0, and an optimum temperature of 50ºC with good thermostability between 40 and 50ºC. As for salts, the protease activity was inhibited in the presence of ZnSO4, and the activity of the proteases from the crude Aspergillus extract, strongly inhibited by PMSF, indicating the presence of a fraction of serine protease in the extract. The extracts of the two selected isolates showed considerable inhibition by EDTA. The milk clotting activity was 240 U mL-1 for the Aspergillus extract and 153 U mL-1 for the crude P. albidus extract. Proteases are important enzymes widely used in the food industry, including cheese. The data suggest that these fungi have the potential to produce these enzymes for usage in cheese making The study evaluated the production of proteases in solid-state fermentation using wheat bran as a substrate. The best producing isolates were used to obtain crude extract which was evaluated for optimal pH and temperature, thermostability, effect of salts and activity against inhibitors. The studied fungi were Aspergillus sp. 125, Fusarium sp. 132, Fusarium sp. 206, Pleurotus albidus 018 and Pleurotus pulmonarius CCB20. The isolates with better results (Aspergillus sp. and P. albidus), showed protease activity with an optimum pH of 7.0, and an optimum temperature of 50ºC with good thermostability between 40 and 50ºC. As for salts, the protease activity was inhibited in the presence of ZnSO4, and the activity of the proteases from the crude Aspergillus extract, strongly inhibited by PMSF, indicating the presence of a fraction of serine protease in the extract. The extracts of the two selected isolates showed considerable inhibition by EDTA. The milk clotting activity was 240 U mL-1 for the Aspergillus extract and 153 U mL-1 for the crude P. albidus extract. Proteases are important enzymes widely used in the food industry, including cheese. The data suggest that these fungi have the potential to produce these enzymes for usage in cheese making

Since laccase acts specifically in lignin, the major contributor to biomass recalcitrance, this biocatalyst represents an important alternative to the pretreatment of lignocellulosic biomass. Therefore, this study investigates the laccase pretreatment and climate change effects on the hydrolytic performance of Panicum maximum. Through a Trop-T-FACE system, P. maximum grew under current (Control (C)) and future climate conditions: elevated temperature (2 °C more than the ambient canopy temperature) combined with elevated atmospheric CO2 concentration(600 μmol mol−1), name as eT+eC. Pretreatment using a laccase-rich crude extract from Lentinus sajor caju was optimized through statistical strategies, resulting in an increase in the sugar yield of P. maximum biomass (up to 57%) comparing to non-treated biomass and enabling hydrolysis at higher solid loading, achieving up to 26 g L−1. These increments are related to lignin removal (up to 46%) and lignin hydrophilization catalyzed by laccase. Results from SEM, CLSM, FTIR, and GC-MS supported the laccase-catalyzed lignin removal. Moreover, laccase mitigates climate effects, and no significant differences in hydrolytic potential were found between C and eT+eC groups. This study shows that crude laccase pretreatment is a potential and sustainable method for biorefinery solutions and helped establish P. maximum as a promising energy crop.

Climate change is expected to affect rainfall dynamics and the global average temperature. Here, we evaluated the effects of those changes, the intense water deficit and warming (+2 °C), on a tropical grassland soil. We tested the correlation between soil extracellular enzyme activities (EEA) and soil respiration (CO2 efflux) and temperature and soil water content (SWC). A climate change simulation was performed in a field experiment using a temperature free-air-controlled enhancement facility. SWC was the main driver of changes in EEA. The most affected enzymes were β-glucosidase, xylanase and phosphatase. As SWC declined, the potential activity of β-glucosidase and xylanase decreased, while the activity of phosphatase and CO2 efflux increased (P

In this study we evaluated the antioxidant capacity, antimicrobial activity, and cytotoxicity of an aqueous extract of the Pleurotus ostreatoroseus mushroom, which was cooked. Fresh basidiocarps were heated and steamed at 100°C and the resulting aqueous extract was assessed before and after in vitro digestion. Cooking reduced the amounts of phenolic compounds in the extract. The antioxidant activity of the extract was evaluated through the use of 4 methods. The lowest half-maximal effective concentration (EC50) against ABTS radicals was 0.057 ± 0.002 mg/mL for the uncooked basidiocarp extract. Cooking and the digestive process led to decreased activity (P > 0.05) against ABTS and DPPH radicals. A significant increase in chelating activity (P > 0.05) occurred after the basidiocarps were cooked (EC50 = 0.279 ± 0.007 mg/mL). The reducing power did not significantly change among the different extracts. The uncooked basidiocarp extract was cytotoxic to Vero cells. After cooking and subsequent in vitro digestion, the cytotoxicity of the extracts decreased (P < 0.05). Bacillus subtilis, Staphylococcus aureus, and Candida albicans were sensitive to the fresh mushroom extract. The data showed that after being cooked and digested, the P. ostreatoroseus mushroom maintains antioxidant activity and has a low cytotoxic effect.

Bisphenol A (BPA) is an endocrine disruptor compound that is continuously released into the environment and is barely degraded in wastewater treatment plants. A previous study showed that free Pleurotus ostreatus laccase is efficient in degrading BPA producing less toxic metabolites. In the present study, this laccase was successfully immobilized onto MANAE-agarose, improving its efficiency in degrading BPA and its thermal and storage stabilities. In addition to this, the immobilized enzyme retained >90% of its initial capability to degrade BPA after 15 cycles of reuse. P. ostreatus laccase immobilized onto MANAE-agarose could be an economical alternative for large scale degradation of BPA in aqueous systems.