Production of Lignocellulolytic Enzymes and Phenolic Compounds by Lentinus strigosus from the Amazon Using Solid-State Fermentation (SSF) of Guarana (Paullinia cupana) Residue.

The Amazon rainforest has a rich biodiversity, and studies of Basidiomycete fungi that have biomolecules of biotechnological interest are relevant. The use of lignocellulosic biomass in biotechnological processes proposes an alternative use, and also adds value to the material when employed in the bioconversion of agro-industrial waste. In this context, this study evaluate the production of lignocellulolytic enzymes (carboxymethylcellulases (CMCase), xylanase, pectinase, laccase) as well as phenolic compounds and proteases by solid-state fermentation (SSF) using the fungus Lentinus strigosus isolated from Amazon. The guarana (Paullinia cupana) residue was characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). SSF was carried out with 60% humidification of the residue, at 30 °C, for 10 days. The lignocellulosic biomass presented fragmented structures with irregular shapes and porosities, and was mainly constituted by cellulose (19.16%), hemicellulose (32.83%), and lignin (6.06%). During the SSF, significant values of CMCase (0.84 U/g) on the 8th day, xylanase (1.00 U/g) on the 7th day, pectinase (2.19 U/g) on the 6th day, laccase (176.23 U/mL) on the 5th day, phenolic compounds (10.27 µg/mL) on the 1st day, soluble proteins (0.08 mg/mL) on the 5th day, and protease (8.30 U/mL) on the 6th day were observed. In general, the agro-industrial residue used provided promising results as a viable alternative for use as a substrate in biotechnological processes.

Nutritional and Bioactive Properties of an Amazon Wild Oyster Culinary-Medicinal Mushroom, Pleurotus ostreatus (Agaricomycetes): Contributions to Functional Food and Human Health.

A wild Amazonian strain of Pleurotus ostreatus (Jacq.: Fr.) P. Kumm. was cultivated using local agroindustrial wastes-açai seeds (AS) and elephant grass straw (EGS)-as substrates and evaluated for its nutritional composition and bioactivities. Basidiomata presented higher contents of protein (27.19%) and dietary fiber (18.57%) when grown on AS, while lipids (2.26%), nonfiber carbohydrates (53.21%), and metabolizable energy (304.02 kcal/100 g) were higher on EGS substrate. Methanolic extracts of P. ostreatus grown on AS also provided a higher phenolic content (31.24 mg gallic acid equivalents/g extract) and greater antioxidant activity, scavenging 82.60% and 91.13% of DPPH· and ABTS·+ radicals, respectively, while chelating ability of Fe2+ was higher on EGS mushroom extracts (74.34%). Hemagglutinating activity of 1,997 HA U/mg protein was observed solely in the aqueous extracts of AS-grown mushrooms. Higher proteolytic activity was observed in aqueous extracts from mushrooms grown on EGS (219.10 U/mg protein), and their saline extract was the sole one with fibrinolytic activity (3.14 mm2). Both substrates and extractions yielded similar activity of protease inhibitors, with higher inhibition of serine than cysteine proteases. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis profiling showed protein bands related to lectins, proteases, fibrinolytic enzymes, and protease inhibitors. Thus, this wild Amazonian strain has great nutritional potential and produces biomolecules that can contribute to important applications in food, health, and industry.

Applicability of the use of waste from different banana cultivars for the cultivation of the oyster mushroom.

The objective of this research was to evaluate the oyster mushroom Pleurotus ostreatus- (Jacq.: Fr.) Kumm. cultivation in substrates based on different combinations of wastes (leaf, pseudo-stem and pseudo-stem + leaf) and banana cultivars - Musa spp. (Thap Maeo, Prata AnãPelipita and Caipira) during 49 days. Organic matter loss in the substrate by action of the fungus was also evaluated during that period. It was verified that the pseudo-stem waste provided the best averages of biological efficiency among all cultivars tested and best rates were obtained by Thap Maeo (61.5%). The highest organic matter loss (OML) was obtained from pseudo-stem + leaf wastes (Prata Anã 78.6%; Thap Maeo - 67.6%; Pelipita - 64.8%; Caipira - 60.6%). Therefore, the use of those wastes showed itself viable for P. ostreatus cultivation due to its availability and low cost, besides decreasing discards to environment.