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BACKGROUND Difficulties in bioprocess monitoring are a drawback of solid-state fermentation ( SSF). Specifically, monitoring of enzyme activities in SSF is not an easy task. This work aimed to calibrate partial least squares ( PLS) and artificial neural network ( ANN) models for inferring protease and amylase activities, as well as protein concentration, from UV-Vis spectra of aqueous extracts of samples removed during SSF using Rhizopus microsporus var. oligosporus. RESULTS SSFs were performed using single agro-industrial wastes (wheat bran, type II wheat flour, sugarcane bagasse and soybean meal) and ternary mixtures of them. Enzyme activities and protein concentrations in the aqueous extracts were quantified biochemically. The corresponding UV-Vis spectra of diluted extracts were also collected. The prediction quality of the ANN was higher than that of the PLS model. The relative errors considering the range for amylolytic and proteolytic enzymes were 4% (3-442 U g−1) and 6% (0-256 U g−1), respectively, for the best ANN architectures (8 and 6 neurons in hidden layer, respectively). CONCLUSION These results, in combination with correlation coefficients (R > 0.94), suggest that this approach is suitable for developing a chemosensor for monitoring SSFs, reducing the analytical work for quantification of enzyme activities. No satisfactory results were obtained for protein concentration. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Culture medium is a key element to be defined when biotechnologies are chosen for agro-industrial wastes reutilization. This work aimed at definition of culture medium composition using four agro-industrial wastes (wheat bran, type II wheat flour, soybean meal and sugarcane bagasse) in solid-state fermentation ( SSF) of Rhizopus oligosporus, for high-level production of amylases through approaches based on artificial intelligence ( AI) or response surface methodologies ( RSM). First, substrates were individually assessed. Then, I-optimal mixture experimental designs were performed to determine the influence of two sets of ternary agro-industrial waste mixtures on amylase and specific amylase activities. RESULTS The best individual substrate for amylases production was wheat bran (392.5 U g−1). As a rule, no significant interactions among substrates affecting amylase activities were observed for ternary systems and the approaches under consideration. A significant exception was the amylolytic activity for mixtures composed of wheat bran (91% w/w) and soybean meal (9% w/w). This finding was confirmed analytically by a combination of artificial neural network ( ANN) and genetic algorithm ( GA). The AI approach improved modelling quality with respect to RSM for production of fungal amylases in SSF. CONCLUSION The I-optimal design in conjunction with ANN-GA is suggested to optimize accurately culture medium to maximize amylase production by SSF. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Sugarcane bagasse is an important lignocellulosic material studied for the production of xylooligosaccharides (XOS). Some XOS are considered soluble dietary fi bre, with low caloric value and prebiotic eff ect, but they are expensive and not easily available. In a screening of 138 fungi, only nine were shortlisted, and just Aspergillus fumigatus M51 (35.6 U/mL) and A. fumigatus U2370 (28.5 U/mL) were selected as the most significant producers of xylanases. These fungi had low β-xylosidase activity, which is desirable for the production of XOS. The xylanases from Trichoderma reesei CCT 2768, A. fumigatus M51 and A. fumigatus U2370 gave a significantly higher XOS yield, 11.9, 14.7 and 7.9% respectively, in a 3-hour reaction with hemicellulose from sugarcane bagasse. These enzymes are relatively thermostable at 40-50 °C and can be used in a wide range of pH values. Furthermore, these xylanases produced more prebiotic XOS (xylobiose and xylotriose) when compared with a commercial xylanase. The xylanases from A. fumigatus M51 reached a high level of XOS production (37.6%) in 48-72 h using hemicellulose extracted from sugarcane bagasse. This yield represents 68.8 kg of prebiotic XOS per metric tonne of cane bagasse. In addition, in a biorefinery, aft er hemicellulose extraction for XOS production, the residual cellulose could be used for the production of second-generation ethanol. [ABSTRACT FROM AUTHOR]

During specific times of the year, especially dry seasons, tropical forages typically have poor nutritional value due to high contents of neutral and acid detergent fibres, and low crude protein in their composition, which may reduce productivity of ruminant livestock production and lead to increased enteric methane (CH 4 ) emissions per unit of generated product in forage-bases systems. In order to increase fibre degradability and the efficiency of energy utilisation from low-quality forages, exogenous fibrolytic enzymes have been studied. In this assay, we evaluated the effects of increasing dose levels of fibrolytic enzymes extract (FEE) produced by Trichoderma reesei on in vitro rumen organic matter degradability, fermentation parameters, total gas and CH 4 production of tropical forages. Forage samples were analysed for their bromatological composition, and enzyme activity from FEE was performed for xylanase and endoglucanase. The in vitro gas production technique was used in a 5 × 3 factorial arrangement with five FEE dose levels (0, 5, 50, 500 and 5,000 µl) and three substrates (Cynodon spp., Panicum maximum and Cenchrus ciliaris L.). The highest dose level of FEE increased degradability, total gas and CH 4 production in all substrates (p < .05). Butyrate concentration also increased while acetate:propionate ratio and pH decreased with the addition of FEE (p < .05). These results indicated that the use of fibrolytic enzymes can be a reliable strategy to improve degradability of low-quality forages, contributing to the sustainability and intensification of livestock production in tropical countries., (© 2020 Blackwell Verlag GmbH.)

The present study evaluated the anti-inflammatory and analgesic properties of Agave sisalana Perrine in classic models of inflammation and pain. The hexanic fraction of A. sisalana (HFAS) was obtained by acid hydrolysis followed by hexanic reflux. Anti-inflammatory properties were examined in three acute mouse models (xylene ear oedema, hind paw oedema and pleurisy) and a chronic mouse model (granuloma cotton pellet). The antinociceptive potential was evaluated in chemical (acetic-acid) and thermal (tail-flick and hot-plate test) models of pain. When given orally, HFAS (5, 10, 25 and 50 mg/kg) reduced ear oedema (p < 0.0001; 52%, 71%, 62% and 42%, respectively). HFAS also reduced hind paw oedema at doses of 10 mg/kg and 25 mg/kg (p < 0.05; 42% and 58%, respectively) and pleurisy at doses of 10 mg/kg and 25 mg/kg (41% and 50%, respectively). In a chronic model, HFAS reduced inflammation by 46% and 58% at doses of 10 mg/kg and 25 mg/kg, respectively. Moreover, this fraction showed analgesic properties against the abdominal writhing in an acetic acid model (at doses of 5-25 mg/kg) with inhibitory rates of 24%, 54% and 48%. The HFAS also showed an increased latency time in the hot-plate (23% and 28%) and tail-flick tests (61% and 66%) for the 25 mg/kg and 50 mg/kg doses, respectively. These results suggest that HFAS has anti-inflammatory and analgesic properties.