Production of Enzymes and Biotransformation of Orange Waste by Oyster Mushroom, <i>Pleurotus pulmonarius</i>(Fr.) Quél.

The wood-decay fungi are able to bioconvert a wide variety of lignocellulosic residues due to the secretion of extracellular enzymes. The use of agricultural wastes as substrate for mushroom cultivation or enzymes production can help to solve environmental problems caused by inadequate discharge in the nature. The production of hydrolytic and oxidative enzymes by Pleurotus pulmonarius developed in solid state system using orange waste as substrate was evaluated in this work. Among the hydrolytic enzymes, pectinase was the main enzyme produced by the fungus, presenting the highest enzymatic activity of 9.4 U/mL after 35 days of cultivation. Considering the oxidative enzymes, laccase was the main enzyme produced with maximal activity of 12.2 U/mL obtained after 20 days of cultivation. Low enzyme levels of manganese peroxidase, β-glucosidase and β-xy-losidase were detected with activity peaks at the end of the cultivation. The enzymatic levels of amylase, carboxymethyl cellulase and xylanase were similar and less than 1.5 U/mL. No aryl-alcohol oxidase activity was detected. NDF, ADF and cellulose values increased during 45 days of cultivation. There was no lignin degradation during the study period and the fungus culture in orange solid waste caused protein enrichment in the substrate. Our results demonstrate that P. pulmonarius was an efficient producer of two important industrial enzymes, pectinase and laccase in a cheap solid state system using orange waste as substrate.

Heuristic Order Reduction of NARX-OBF models Applied to Nonlinear System Identification

Nonlinear system identification concerns the determination of the model structure and its parameters.Although the designers often seek the best model for each system,it can be tricky to determine,at the same time,the best structure and the parameters which optimize the model performance.This paper proposes the use of a Genetic Algorithm,GA,and the Levenberg-Marquardt,LM,method to obtain the model parameters,as well as perform the order reduction of the model.In order to validate the proposed methodology,the identification of a magnetic levitator,operating in closed loop,was performed.The class NARX-OBF,Nonlinear Auto Regressive with eXogenous input-Orthonormal Basis Function,was used.The use of OBF functions aims to reduce the number of terms in NARX models.Once the model is found,the order reduction is performed using GA and LM,in a hybrid application,capable of determining the model parameters and reducing the original model order,simultaneously.The results show,considering the inherent trade-of between accuracy and computational effort,the proposed methodology provided an implementation with good mean square error,when compared with the full NARX-OBF model.

Prebiotics in non-dairy products:Technological and physiological functionality,challenges,and perspectives

Vegan consumers look for fresh,tasty,and nutritious products that use eco/animal-friendly ingredients.Prebiotics are substrates selectively utilized by host microorganisms conferring a health benefit.This study aimed to overview the potentially vegan products added with prebiotics,their health benefits,and the main technological and sensory challenges.The main potentially vegan products added with prebiotics studied were based on water-soluble plant-based extracts(fermented beverages,frozen desserts,cheese analog),fruits(fruit juices,fruit jelly,and ready to eat fruits),and cereals(snack bars,granola bars,bread,and cookies).The main prebiotic compounds used were inulin,fructooligosaccharides,oligofructose,polydextrose,and xylooligosaccharides.The effects of prebiotic on food products’,host health,and technological and sensory properties depended on the prebiotic type and dosage,food matrix,and subject type.The positive health effects were related to skin health,gut microbiota improvement,hypocholesterolemic impact,reduction of the risk of metabolic diseases,and improvements in postprandial blood glucose and insulin response.Prebiotics could improve vegan products’technological and sensory properties,such as fermentation time,texture and rheological properties,storage length,sensory acceptance,and probiotic survival.Furthermore,they could increase the concentration and/or bioaccessibility of phenolic compounds and vitamins.However,it is of paramount importance the determination of prebiotic stability.The trends direct to new prebiotic compounds based on microalgae,fruit and cereal by-products,and seeds.This review provides industries and researchers with important information about prebiotics and vegan products.

Microencapsulation with spray-chilling as an innovative strategy for probiotic low sodium requeijao cremoso processed cheese processing

The effect of sodium reduction and Lactobacillus acidophilus addition(free or microencapsulated)on the quality parameters of requeijao cremoso processed cheese was assessed for 90 days at 5℃.Three formulations were prepared:(CONT)regular salt content and curd fusion(90℃/2 min),(FREE)reduced salt content+free probiotic culture added after curd fusion(90℃/2 min),and(MICRO)reduced salt content+microencapsulated probiotic culture added before curd fusion(70℃/5 min).FREE and MICRO formulations showed increased monounsaturated and polyunsaturated fatty acid content,improved health indices(decreases in thrombogenic index and increases in desirable fatty acid index),and altered rheological properties(higher consistency index,apparent viscosity,elastic properties,and gel strength).In addition,the MICRO formulation showed higher texture sensory acceptance and probiotic counts higher than 6 log CFU/g during storage and simulated gastrointestinal conditions.Overall,microencapsulation of probiotics with spray chilling represents an innovative solution in requeijao cremoso processed cheese.

Chromium from Hydrolyzed Leather Affects Soybean Growth and Nodulation

Hydrolyzed leather, obtained from industrial leather waste, is an organic nitrogenous fertilizer with a high chromium(Cr) content.Soybean crops can be adversely affected by the presence of residual Cr in soil after application of hydrolyzed leather fertilizer. The aim of this work was to assess the effect of hydrolyzed leather on Cr absorption, root development, and symbiotic nodulation of soybean plants grown on three different soils including two Lixisols and a Gleysol. These soils were previously fertilized with hydrolyzed leather at three different rates(0.0, 0.1, and 0.8 kg m^(-2)). Soybean shoot height, root development, nodulation, and mineral nutrient concentrations in plant tissues were determined after 45 d of crop growth. The application of hydrolyzed leather significantly increased Cr content in soil and Cr uptake by plants. Surprisingly, Cr was stored mainly in the aerial part of the plants. The presence of Cr had an adverse impact on shoot dry matter(41% reduction) and number of nodules(49% reduction) per plant grown on the soil with the lowest cation exchange capacity. However, no other significant effect was observed in nodule weight, diameter, or any other measured parameters.