Enzymatic hydrolysis of pretreated sugar cane bagasse using Penicillium funiculosum and Trichoderma harzianum cellulases

In this study, we investigated the enzymatic hydrolysis of pretreated sugarcane bagasse using eight different enzymatic blends obtained from concentrated crude enzyme extracts produced by Penicillium funiculosum and Trichoderma harzianum as well as from the extracts in combination with a commercial enzymatic cocktail. The influence of different levels of biomass delignification, degree of crystallinity of lignicellulose, composition of enzymatic activities and BSA on enzymatic hydrolysis yields (HYs) was evaluated. Our X-ray diffraction studies showed that crystallinity of lignocellulose is not a key determinant of its recalcitrance toward enzymatic hydrolysis. In fact, under the experimental conditions of our study, an increase in crystallinity of lignocellulosic samples resulted in increased glucose release by enzymatic hydrolysis. Furthermore, under the same conditions, the addition of BSA had no significant effect on enzymatic hydrolysis. The most efficient enzyme blends were obtained by mixing a commercial enzymatic cocktail with P. funiculosum or T. harzianum cellulase preparations (HYs above 97%) followed by the concentrated extract of P. funiculosum alone (HY= 88.5%). Increased hydrolytic efficiencies appeared to correlate with having an adequate level of both beta-glucosidase and xylanase activities in the blends. (C) 2011 Elsevier Ltd. All rights reserved.

Sisal chemically modified with lignins: Correlation between fibers and phenolic composites properties

Sisal fibers have been chemically modified by reaction with lignins, extracted from sugarcane bagasse and Pinus-type wood and then hydroxymethylated, to increase adhesion in resol-type phenolic thermoset matrices. Inverse gas chromatography (IGC) results showed that acidic sites predominate for unmodified/modified sisal fibers and for phenolic thermoset, indicating that the phenolic matrix has properties that favor the interaction with sisal fibers. The IGC results also showed that the phenolic thermoset has a dispersive component closer to those of the modified fibers suggesting that thermoset interactions with the less polar modified fibers are favored. Surface SEM images of the modified fibers showed that the fiber bundle deaggregation increased after the treatment, making the interfibrillar structure less dense in comparison with that of unmodified fibers, which increased the contact area and encouraged microbial biodegradation in simulated soil. Water diffusion was observed to be faster for composites reinforced with modified fibers, since the phenolic resin penetrated better into modified fibers, thereby blocking water passage through their channels. Overall, composites` properties showed that modified fibers promote a significant reduction in the hydrophilic character, and consequently of the reinforced composite without a major effect on impact strength and with increased storage modulus. (c) 2008 Elsevier Ltd. All rights reserved.

Optimization of fibrolytic enzyme production by Aspergillus japonicus C03 with potential application in ruminant feed and their effects on tropical forages hydrolysis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Predição da digestibilidade da matéria seca de rações em coelhos em crescimento

O experimento foi realizado com o objetivo de predizer a digestibilidade da matéria seca (MS) de rações para coelhos em crescimento mediante equações baseadas no conceito de entidade nutritiva ideal. Foram usados 100 coelhos do Grupo Genético Botucatu, com 42 dias de idade. Testaram-se 16 rações contendo alimentos volumosos (papel, sabugo de milho, bagaço de cana ou maravalha de pínus), mais milho, farelo de soja, óleo de soja, caulim e sal comum. Os volumosos foram incluídos em quatro níveis, para se obter 22, 28, 34 ou 40% de fibra em detergente neutro (FDN) e 16% de proteína bruta (PB). O experimento foi realizado em duas fases, em delineamento experimental de blocos ao acaso. Observou-se efeito linear positivo da FDN sobre o consumo de MS. As médias de digestibilidade da MS variaram entre 60,10 e 80,78%. Houve efeito linear negativo da FDN, bem como interação do teor de FDN × volumoso, sobre a digestibilidade aparente da MS. Ao contrário dos componentes fibrosos, a proteína bruta PB e o conteúdo celular comportaram-se como entidade nutritiva ideal. Para predizer a digestibilidade da MS, testaram-se três modelos e o melhor baseou-se no teor de conteúdo celular, com digestibilidade verdadeira fixada em 1; outro no teor de FDN, cuja digestibilidade foi predita mediante uma equação empírica; e o terceiro, na perda endógena de conteúdo celular, considerada proporcional ao consumo de MS. A principal dificuldade na formulação de modelos para predizer a digestibilidade aparente da MS em coelhos é estimar com precisão a digestibilidade da FDN e a perda endógena de conteúdo celular. É necessário avaliar em estudos futuros o uso de maiores níveis de fibra nas rações. Para rações com níveis de fibra situados na amplitude deste estudo, recomenda-se usar o modelo 3, que inclui, além da fibra em detergente neutro, a fibra em detergente ácido e a lignina.

Evaluation of organic molecules originated during composting process

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influence of the diet on in situ disappearance of dry matter, organic matter, and neutral detergent fiber of hydrolysed sugar cane bagasse

The effects of two diets based on hydrolysed sugarcane bagasse (HSB) and whole cottonseed (WCS), with or without oat hay, were analyzed for the in situ disappearance of dry matter (DM), organic matter (OM) and neutral detergent fiber (NDF) of HSB. Six mature castrated rams with a permanent T ruminai cannula were used in a complete randomized split plot design. The incubation times were 3, 6, 9, 12, 24, 48 and 72h. The diet with oat hay showed higher disappearance indexes for the NDF fraction. Furthermore, the maximum degradation of HSB constituents was reached around 48h of incubation. The diets were T1=64% hydrolyzed sugarcane + 36% whole cottonseed and T2=14% hydrolyzed sugarcane bagasse + 36% cottonseed + 50% oat hay.

Glass-ceramic material from the SiO 2-Al 2O 3-CaO system using sugar-cane bagasse ash (SCBA)

Brazil is the world's largest producer of alcohol and sugar from sugarcane. Currently, sugarcane bagasse is burned in boilers to produce steam and electrical energy, producing a huge volume of ash. The major component of the ash is SiO 2, and among the minor components there are some mineralizing agents or fluxing. Published works have shown the potential of transforming silicate-based residues into glass-ceramic products of great utility. This work reports the research results of SCBA use to produce glass-ceramics with wollastonite, rankinite and gehlenite as the major phases. These silicates have important applications as building industry materials, principally wollastonite, due to their special properties: high resistance to weathering, zero water absorption, and hardness among others. The glasses (frits) were prepared mixing ash, calcium carbonate and sodium or potassium carbonates as flux agents, in different concentrations. X-ray fluorescence was used to determine the chemical composition of the glasses and their crystallization was assessed by using thermal analysis (DTA/DSC/TGA) and X-ray diffraction. The crystallization kinetics was evaluated using the Kissinger method, giving activation energies ranging from 200 to 600 kJ/mol. © 2011 Ceramic Society of Japan.

Development and Biotechnological Application of a Novel Endoxylanase Family GH10 Identified from Sugarcane Soil Metagenome

Metagenomics has been widely employed for discovery of new enzymes and pathways to conversion of lignocellulosic biomass to fuels and chemicals. In this context, the present study reports the isolation, recombinant expression, biochemical and structural characterization of a novel endoxylanase family GH10 (SCXyl) identified from sugarcane soil metagenome. The recombinant SCXyl was highly active against xylan from beechwood and showed optimal enzyme activity at pH 6,0 and 45°C. The crystal structure was solved at 2.75 Å resolution, revealing the classical (β/α)8-barrel fold with a conserved active-site pocket and an inherent flexibility of the Trp281-Arg291 loop that can adopt distinct conformational states depending on substrate binding. The capillary electrophoresis analysis of degradation products evidenced that the enzyme displays unusual capacity to degrade small xylooligosaccharides, such as xylotriose, which is consistent to the hydrophobic contacts at the +1 subsite and low-binding energies of subsites that are distant from the site of hydrolysis. The main reaction products from xylan polymers and phosphoric acid-pretreated sugarcane bagasse (PASB) were xylooligosaccharides, but, after a longer incubation time, xylobiose and xylose were also formed. Moreover, the use of SCXyl as pre-treatment step of PASB, prior to the addition of commercial cellulolytic cocktail, significantly enhanced the saccharification process. All these characteristics demonstrate the advantageous application of this enzyme in several biotechnological processes in food and feed industry and also in the enzymatic pretreatment of biomass for feedstock and ethanol production. © 2013 Alvarez et al.

Biomass-to-bio-products application of feruloyl esterase from Aspergillus clavatus

The structural polysaccharides contained in plant cell walls have been pointed to as a promising renewable alternative to petroleum and natural gas. Ferulic acid is a ubiquitous component of plant polysaccharides, which is found in either monomeric or dimeric forms and is covalently linked to arabinosyl residues. Ferulic acid has several commercial applications in food and pharmaceutical industries. The study herein introduces a novel feruloyl esterase from Aspergillus clavatus (AcFAE). Along with a comprehensive functional and biophysical characterization, the low-resolution structure of this enzyme was also determined by small-angle X-ray scattering. In addition, we described the production of phenolic compounds with antioxidant capacity from wheat arabinoxylan and sugarcane bagasse using AcFAE. The ability to specifically cleave ester linkages in hemicellulose is useful in several biotechnological applications, including improved accessibility to lignocellulosic enzymes for biofuel production. © 2012 Springer-Verlag Berlin Heidelberg.

Sugarcane vinasse: Environmental implications of its use

The inadequate and indiscriminate disposal of sugarcane vinasse in soils and water bodies has received much attention since decades ago, due to environmental problems associated to this practice. Vinasse is the final by-product of the biomass distillation, mainly for the production of ethanol, from sugar crops (beet and sugarcane), starch crops (corn, wheat, rice, and cassava), or cellulosic material (harvesting crop residues, sugarcane bagasse, and wood). Because of the large quantities of vinasse produced, alternative treatments and uses have been developed, such as recycling of vinasse in fermentation, fertirrigation, concentration by evaporation, and yeast and energy production. This review was aimed at examining the available data on the subject as a contribution to update the information on sugarcane vinasse, from its characteristics and chemical composition to alternatives uses in Brazil: fertirrigation, concentration by evaporation, energy production; the effects on soil physical, chemical and biological properties; its influence on seed germination, its use as biostimulant and environmental contaminant. The low pH, electric conductivity, and chemical elements present in sugarcane vinasse may cause changes in the chemical and physical-chemical properties of soils, rivers, and lakes with frequent discharges over a long period of time, and also have adverse effects on agricultural soils and biota in general. Thus, new studies and green methods need to be developed aiming at sugarcane vinasse recycling and disposal. © 2013 Elsevier Ltd. All rights reserved.

Estudo da hidrólise do bagaço de cana-de-açúcar por fungos filamentosos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação do uso de radiação micro-ondas e ultrassom combinados com agentes químicos como pré-tratamentos de bagaço de cana-de-açúcar para posterior sacarificação enzimática

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Linhagens fúngicas na hidrólise enzimática de bagaço de cana-de-açúcar

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Estudo energético do bagaço de diferentes variedades de cana-de-açucar

Pós-graduação em Química - IBILCE

Utilização de processos oxidativos avançados baseados em ozônio como pré-tratamento para bagaço de cana-de-açúcar, e hidrólise do bagaço pré-tratado com combinado enzimático dos fungos Penicillium viridicatum RFC3 e Trichoderma reesei QM9414

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)