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Abstract The use of residual lignocellulosic biomass appears as an opportunity to obtain high added value products like enzymes. The present work goal was to select basidiomycetes capable of metabolizing empty fruit bunches (EB) or sludge decanter (SD) from the oil palm industry to produce enzymatic cocktails. First, eight macro‐basidiomycetes strains from the Brazilian cerrado were selected based on genomic DNA analyses out of an initial group of 30. The selected basidiomycetes and two ascomycetes (commercial mushrooms) were cultured to obtain ligninolytic and cellulolytic enzymes, respectively. All the extracts produced had proteins, and enzymatic profiles evaluated. The enzymatic hydrolysis of pretreated EB used cocktails of basidiomycetes extracts combined with commercial cellulases or ascomycetes extracts. The best combination of enzymatic extracts for hydrolyses of hydrothermally pretreated EB was the cocktail with Trichoderma reesei, Aspergillus aculeatus, and Pleurotus sp. extracts, reaching 19.7% of glucose yield and 22.8% of xylose yield. These results show that enzymes and sugars are products derivable from residues produced in large quantities by the oil palm industry. This study corroborates the hypothesis that basidiomycetes from the Brazilian cerrado present an enormous biotechnological potential, still unexplored.

The conversion of rice hulls into fermentable saccharides was explored through steam pretreatment employing 2.5% SO2. The interaction between temperature and time was assessed by means of the response surface method to achieve optimum contents of C6-sugars in water-insoluble solids (WIS) and C5-sugars in the liquor. Pretreatment carried out at 218 °C for 2.3 min released liquor containing 55.4 g/L of sugars (29.1 g/L of xylose). In parallel, the WIS was subjected to enzymatic saccharification using different solid and enzyme loads via an experimental design: assays using 22.0% WIS and 20.0 filter paper units (FPU)/g led to 90.6 g/L of glucose, corresponding to a yield of 86.4% and an overall yield of 72.4%. The data reported are the highest ever found for such raw material, making it attractive to compete with conventional lignocellulosic biomass.

ABSTRACT: The current investigation intended to check the influence of Pleurotus albidus extract supplementation on body weight, food intake, glycemia, serum lipids, and oxidative stress parameters. Healthy male C57BL/6 mice were partitioned into two experimental groups: control and P. albidus. The supplementation was performed by gavage (500 mg/kg) for 20 uninterrupted days. During this period, all animals received water and food ad libitum and they had their food ingestion and body weight monitored weekly. After, mice underwent an insulin sensitivity test, followed by euthanasia and biochemical analyses. P. albidus supplementation decreased the body weight and food intake, but it did not change other parameters in healthy mice. This work showed for the first time that the P. albidus extract supplementation presents a promising potential on body weight and food intake control.

Penicillium echinulatum 2HH and Penicillium oxalicum 114-2 are well-known cellulase fungal producers. However, few studies addressing global mechanisms for gene regulation of these two important organisms are available so far. A recent finding that the 2HH wild-type is closely related to P. oxalicum leads to a combined study of these two species. Firstly, we provide a global gene regulatory network for P. echinulatum 2HH and P. oxalicum 114-2, based on TF-TG orthology relationships, considering three related species with well-known regulatory interactions combined with TFBSs prediction. The network was then analyzed in terms of topology, identifying TFs as hubs, and modules. Based on this approach, we explore numerous identified modules, such as the expression of cellulolytic and xylanolytic systems, where XlnR plays a key role in positive regulation of the xylanolytic system. It also regulates positively the cellulolytic system by acting indirectly through the cellodextrin induction system. This remarkable finding suggests that the XlnR-dependent cellulolytic and xylanolytic regulatory systems are probably conserved in both P. echinulatum and P. oxalicum. Finally, we explore the functional congruency on the genes clustered in terms of communities, where the genes related to cellular nitrogen, compound metabolic process and macromolecule metabolic process were the most abundant. Therefore, our approach allows us to confer a degree of accuracy regarding the existence of each inferred interaction.

Plant feedstocks are at the leading front of the biofuel industry based on the potential to promote economical, social and environmental development worldwide through sustainable scenarios related to energy production. Penicillium echinulatum is a promising strain for the bioethanol industry based on its capacity to produce large amounts of cellulases at low cost. The secretome profile of P. echinulatum after grown on integral sugarcane bagasse, microcrystalline cellulose and three types of pretreated sugarcane bagasse was evaluated using shotgun proteomics. The comprehensive chemical characterization of the biomass used as the source of fungal nutrition, as well as biochemical activity assays using a collection of natural polysaccharides, were also performed. Our study revealed that the enzymatic repertoire of P. echinulatum is geared mainly toward producing enzymes from the cellulose complex (endogluganases, cellobiohydrolases and β-glucosidases). Glycoside hydrolase (GH) family members, important to biomass-to-biofuels conversion strategies, were identified, including endoglucanases GH5, 7, 6, 12, 17 and 61, β-glycosidase GH3, xylanases GH10 and GH11, as well as debranching hemicellulases from GH43, GH62 and CE2 and pectinanes from GH28. Collectively, the approach conducted in this study gave new insights on the better comprehension of the composition and degradation capability of an industrial cellulolytic strain, from which a number of applied technologies, such as biofuel production, can be generated.