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Optimization of the Enzymatic Interesterification of Milk Fat and Canola Oil Blends Using Immobilized Rhizopus oryzae Lipase by Response Surface Methodology

NUNES, Gisele Fatima Morais; PAULA, Ariela Veloso de; CASTRO, Heizir Ferreira de; SANTOS, Julio Cesar dos
Fonte: FACULTY FOOD TECHNOLOGY BIOTECHNOLOGY Publicador: FACULTY FOOD TECHNOLOGY BIOTECHNOLOGY
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
45.8%
Blends of milk fat and canola oil (MF:CNO) were enzymatically interesterified (EIE) by Rhizopus oryzne lipase immobilized on polysiloxane-polyvinyl alcohol (SiO(2)-PVA) composite, in a solvent-free system. A central composite design (CCD) was used to optimize the reaction, considering the effects of different mass fractions of binary blends of MF:CNO (50:50, 65:35 and 80:20) and temperatures (45, 55 and 65 degrees C) on the composition and texture properties of the interesterified products, taking the interesterification degree (ID) and consistency (at 10 degrees C) as response variables. For the ID variable both mass fraction of milk fat in the blend and temperature were found to be significant, while for the consistency only mass fraction of milk fat was significant. Empiric models for ID and consistency were obtained that allowed establishing the best interesterification conditions: blend with 65 % of milk fat and 35 %, of canola oil, and temperature of 45 degrees C. Under these conditions, the ID was 19.77 %) and the consistency at 10 degrees C was 56 290 Pa. The potential of this eco-friendly process demonstrated that a product could be obtained with the desirable milk fat flavour and better spreadability under refrigerated conditions.

Biotransformations of Substituted Phenylethanols and Acetophenones by Environmental Bacteria

KAGOHARA, Edna; PELLIZARI, Vivian Helena; COMASSETO, Joao Valdir; ANDRADE, Leandro Helgueira; PORTO, Andre Luiz Meleiro
Fonte: FACULTY FOOD TECHNOLOGY BIOTECHNOLOGY Publicador: FACULTY FOOD TECHNOLOGY BIOTECHNOLOGY
Tipo: Artigo de Revista Científica
Português
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45.8%
Whole cells of hydrocarbon-degrading bacteria, isolated from polluted sediments in the Santos Estuary (Baixada Santista, Sao Paulo, Brazil), were able to catalyse oxidoreduction reactions with various substituted phenylethanols and acetophenones as substrates. A number of substituted phenylethanols were formed with high (>99 %) enantiomeric excess. The results of microbial oxidation of phenylethanols 2, 3, 5-7 by Acinetobacter sp. 6.4T and the reduction of acetophenones 1a-6a by Serratia marcescens 5.4T showed that the bacteria used as biocatalysts in this study present significant potential for exploitation in biotechnological processes. The reduction of prochiral acetophenones by Serratia marcescens 3.5T yielded optically active alcohols with 90-99 % enantiomeric excess, and Acinetobacter sp. 6.4T is a potential biocatalyst for the oxidation of alcohols.; Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP); FAPESP and Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)

Optimal recovery process conditions for manganese-peroxidase obtained by solid-state fermentation of eucalyptus residue using Lentinula edodes

ARANTES, Valdeir; SILVA, Ezequiel M.; MILAGRES, Adriane M. F.
Fonte: PERGAMON-ELSEVIER SCIENCE LTD Publicador: PERGAMON-ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
Português
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45.8%
Enzyme production is a growing field in biotechnology and increasing attention has been devoted to the solid-state fermentation (SSF) of lignocellulosic biomass for production of industrially relevant lignocellulose deconstruction enzymes, especially manganese-peroxidase (MnP), which plays a crucial role in lignin degradation. However, there is a scarcity of studies regarding extraction of the secreted metabolities that are commonly bound to the fermented solids, preventing their accurate detection and limiting recovery efficiency. In the present work, we assessed the effectiveness of extraction process variables (pH, stirring rate, temperature, and extraction time) on recovery efficiency of manganese-peroxidase (MnP) obtained by SSF of eucalyptus residues using Lentinula edodes using statistical design of experiments. The results from this study indicated that of the variables studied, pH was the most significant (p < 0.05%) parameter affecting MnP recovery yield, while temperature, extraction time, and stirring rate presented no statistically significant effects in the studied range. The optimum pH for extraction of MnP was at 4.0-5.0, which yielded 1500-1700 IU kg (1) of enzyme activity at extraction time 4-5 h, under static condition at room temperature. (C) 2011 Elsevier Ltd. All rights reserved.; Fundacdo de Amparo a Pesquisa do Estado de sao Paulo - FAPESP[04/12080-0]; Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior - CAPES

AnSBBR Applied to a Personal Care Industry Wastewater Treatment: Effects of Fill Time, Volume Treated Per Cycle, and Organic Load

RODRIGUES, Jose Alberto Domingues; OLIVEIRA, Ricardo Polisaitis; RATUSZNEI, Suzana Maria; ZAIAT, Marcelo; FORESTI, Eugenio
Fonte: HUMANA PRESS INC Publicador: HUMANA PRESS INC
Tipo: Artigo de Revista Científica
Português
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55.81%
A study was performed regarding the effect of the relation between fill time, volume treated per cycle, and influent concentration at different applied organic loadings on the stability and efficiency of an anaerobic sequencing batch reactor containing immobilized biomass on polyurethane foam with recirculation of the liquid phase (AnSBBR) applied to the treatment of wastewater from a personal care industry. Total cycle length of the reactor was 8 h (480 min). Fill times were 10 min in the batch operation, 4 h in the fed-batch operation, and a 10-min batch followed by a 4-h fed batch in the mixed operation. Settling time was not necessary since the biomass was immobilized and decant time was 10 min. Volume of liquid medium in the reactor was 2.5 L, whereas volume treated per cycle ranged from 0.88 to 2.5 L in accordance with fill time. Influent concentration varied from 300 to 1,425 mg COD/L, resulting in an applied volumetric organic load of 0.9 and 1.5 g COD/L.d. Recirculation flow rate was 20 L/h, and the reactor was maintained at 30 A degrees C. Values of organic matter removal efficiency of filtered effluent samples were below 71% in the batch operations and above 74% in the operations of fed batch followed by batch. Feeding wastewater during part of the operational cycle was beneficial to the system...

AnSBBR Applied to the Treatment of Metalworking Fluid Wastewater: Effect of Organic and Shock Load

CARVALHINHA, Pedro P.; FLORES, Anderson; RODRIGUES, Jose A. D.; RATUSZNEI, Suzana M.; ZAIAT, Marcelo; FORESTI, Eugenio
Fonte: HUMANA PRESS INC Publicador: HUMANA PRESS INC
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
55.78%
An investigation was performed regarding the application of a mechanically stirred anaerobic sequencing batch biofilm reactor containing immobilized biomass on inert polyurethane foam (AnSBBR) to the treatment of soluble metalworking fluids to remove organic matter and produce methane. The effect of increasing organic matter and reactor fill time, as well as shock load, on reactor stability and efficiency have been analyzed. The 5-L AnSBBR was operated at 30 A degrees C in 8-h cycles, agitation of 400 rpm, and treated 2.0 L effluent per cycle. Organic matter was increased by increasing the influent concentration (500, 1,000, 2,000, and 3,000 mg chemical oxygen demand (COD)/L). Fill times investigated were in the batch mode (fill time 10 min) and fed-batch followed by batch (fill time 4 h). In the batch mode, organic matter removal efficiencies were 87%, 86%, and 80% for influent concentrations of 500, 1,000, and 2,000 mgCOD/L (1.50, 3.12, and 6.08 gCOD/L.d), respectively. At 3,000 mgCOD/L (9.38 gCOD/L.d), operational stability could not be achieved. The reactor managed to maintain stability when a shock load twice as high the feed concentration was applied, evidencing the robustness of the reactor to potential concentration variations in the wastewater being treated. Increasing the fill time to 4 h did not improve removal efficiency...

Effect of Organic Load on the Performance and Methane Production of an AnSBBR Treating Effluent from Biodiesel Production

BEZERRA, Roberto Antonio; RODRIGUES, Jose Alberto Domingues; RATUSZNEI, Suzana Maria; CANTO, Catarina Simone Andrade; ZAIAT, Marcelo
Fonte: HUMANA PRESS INC Publicador: HUMANA PRESS INC
Tipo: Artigo de Revista Científica
Português
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45.8%
Currently, there is an increasing demand for the production of biodiesel and, consequently, there will be an increasing need to treat wastewaters resulting from the production process of this biofuel. The main objective of this work was, therefore, to investigate the effect of applied volumetric organic load (AVOL) on the efficiency, stability, and methane production of an anaerobic sequencing batch biofilm reactor applied to the treatment of effluent from biodiesel production. As inert support, polyurethane foam cubes were used in the reactor and mixing was accomplished by recirculating the liquid phase. Increase in AVOL resulted in a drop in organic matter removal efficiency and increase in total volatile acids in the effluent. AVOLs of 1.5, 3.0, 4.5 and 6.0 g COD L(-1) day(-1) resulted in removal efficiencies of 92%, 81%, 67%, and 50%, for effluent filtered samples, and 91%, 80%, 63%, and 47%, for non-filtered samples, respectively, whereas total volatile acids concentrations in the effluent amounted to 42, 145, 386 and 729 mg HAc L(-1), respectively. Moreover, on increasing AVOL from 1.5 to 4.5 g COD L(-1) day(-1) methane production increased from 29.5 to 55.5 N mL CH(4) g COD(-1). However, this production dropped to 36.0 N mL CH(4) g COD(-1) when AVOL was increased to 6.0 g COD L(-1) day(-1)...

Genetic structure and biology of Xylella fastidiosa strains causing disease in citrus and coffee in Brazil

ALMEIDA, Rodrigo P. P.; NASCIMENTO, Fernanda E.; CHAU, John; PRADO, Simone S.; TSAI, Chi-Wei; LOPES, Silvio A.; LOPES, Joao R. S.
Fonte: AMER SOC MICROBIOLOGY Publicador: AMER SOC MICROBIOLOGY
Tipo: Artigo de Revista Científica
Português
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45.79%
Xylella fastidiosa is a vector-borne, plant-pathogenic bacterium that causes disease in citrus (citrus variegated chlorosis [CVC]) and coffee (coffee leaf scorch [CLS]) plants in Brazil. CVC and CLS occur sympatrically and share leafhopper vectors; thus, determining whether X. fastidiosa isolates can be dispersed from one crop to another and cause disease is of epidemiological importance. We sought to clarify the genetic and biological relationships between CVC- and CLS-causing X. fastidiosa isolates. We used cross-inoculation bioassays and microsatellite and multilocus sequence typing (MLST) approaches to determine the host range and genetic structure of 26 CVC and 20 CLS isolates collected from different regions in Brazil. Our results show that citrus and coffee X. fastidiosa isolates are biologically distinct. Cross-inoculation tests showed that isolates causing CVC and CLS in the field were able to colonize citrus and coffee plants, respectively, but not the other host, indicating biological isolation between the strains. The microsatellite analysis separated most X. fastidiosa populations tested on the basis of the host plant from which they were isolated. However, recombination among isolates was detected and a lack of congruency among phylogenetic trees was observed for the loci used in the MLST scheme. Altogether...

Ammonia volatilization in soil treated with tannery sludge

MARTINES, A. M.; NOGUEIRA, M. A.; SANTOS, C. A.; NAKATANI, A. S.; ANDRADE, C. A.; COSCIONE, A. R.; CANTARELLA, H.; SOUSA, J. P.; CARDOSO, E. J. B. N.
Fonte: ELSEVIER SCI LTD Publicador: ELSEVIER SCI LTD
Tipo: Artigo de Revista Científica
Português
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45.81%
The utilization of tannery sludge in agricultural areas can be an alternative for its disposal and recycling. Despite this procedure may cause the loss of nitrogen by ammonia volatilization, there is no information about this process in tropical soils. For two years a field experiment was carried out in Rolandia (Parana State, Brazil), to evaluate the amount of NH(3) volatilization due to tannery sludge application on agricultural soil. The doses of total N applied varied from zero to 1200 kg ha(-1), maintained at the surface for 89 days, as usual in this region. The alkalinity of the tannery sludge used was equivalent to between 262 and 361 g CaCO(3) per kg. Michaelis-Menten equation was adequate to estimate NH(3)-N volatilization kinetics. The relation between total nitrogen applied as tannery sludge and the potentially volatilized NH(3)-N, calculated by the chemical-kinetics equation resulted in an average determination coefficient of 0.87 (P > 0.01). In this period, the amount of volatilized NH(3) was more intense during the first 30 days; the time to reach half of the maximum NH(3) volatilization (K(m)) was 13 an 9 days for the first and second experiments, respectively. The total loss as ammonia in the whole period corresponded in average to 17.5% of the total N applied and to 35% of the NH(4)(+)-N present in the sludge. If tannery sludge is to be surface applied to supply N for crops...

Endophytic Colonization of Potato (Solanum tuberosum L.) by a Novel Competent Bacterial Endophyte, Pseudomonas putida Strain P9, and Its Effect on Associated Bacterial Communities

ANDREOTE, Fernando Dini; ARAUJO, Welington L. de; AZEVEDO, Joao L. de; ELSAS, Jan Dirk van; ROCHA, Ulisses Nunes da; OVERBEEK, Leonard S. van
Fonte: AMER SOC MICROBIOLOGY Publicador: AMER SOC MICROBIOLOGY
Tipo: Artigo de Revista Científica
Português
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45.79%
Pseudomonas putida strain P9 is a novel competent endophyte from potato. P9 causes cultivar-dependent suppression of Phytophthora infestans. Colonization of the rhizoplane and endosphere of potato plants by P9 and its rifampin-resistant derivative P9R was studied. The purposes of this work were to follow the fate of P9 inside growing potato plants and to establish its effect on associated microbial communities. The effects of P9 and P9R inoculation were studied in two separate experiments. The roots of transplants of three different cultivars of potato were dipped in suspensions of P9 or P9R cells, and the plants were planted in soil. The fate of both strains was followed by examining colony growth and by performing PCR-denaturing gradient gel electrophoresis (PCR-DGGE). Colonies of both strains were recovered from rhizoplane and endosphere samples of all three cultivars at two growth stages. A conspicuous band, representing P9 and P9R, was found in all Pseudomonas PCR-DGGE fingerprints for treated plants. The numbers of P9R CFU and the P9R-specific band intensities for the different replicate samples were positively correlated, as determined by linear regression analysis. The effects of plant growth stage, genotype, and the presence of P9R on associated microbial communities were examined by multivariate and unweighted-pair group method with arithmetic mean cluster analyses of PCR-DGGE fingerprints. The presence of strain P9R had an effect on bacterial groups identified as Pseudomonas azotoformans...

Correlation between Environmental Factors and Prevalence of Vibrio parahaemolyticus in Oysters Harvested in the Southern Coastal Area of Sao Paulo State, Brazil

COSTA SOBRINHO, Paulo de Souza; DESTRO, Maria T.; FRANCO, Bernadette D. G. M.; LANDGRAF, Mariza
Fonte: AMER SOC MICROBIOLOGY Publicador: AMER SOC MICROBIOLOGY
Tipo: Artigo de Revista Científica
Português
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45.79%
The presence of Vibrio parahaemolyticus in 123 oyster samples collected from an estuary on the southern coast of Sao Paulo state, Brazil, was investigated. Of the 123 samples, 99.2% were positive with densities ranging from <3 to 10(5) most probable number (MPN)/g. Densities correlated significantly with water temperature (r = 0.48; P < 0.001) but not with salinity (r = -0.09; P = 0.34). The effect of harvest site on counts was not significant (P > 0.05). These data provide information for the assessment of exposure of V. parahaemolyticus in oysters at harvest.; Conselho Nacional de Pesquisa Cientifico e Tecnologico (CNPq); Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)

LPS Removal from an E. Coli Fermentation Broth Using Aqueous Two-Phase Micellar System

LOPES, Andre M.; MAGALHAES, Perola O.; MAZZOLA, Priscila G.; RANGEL-YAGUI, Carlota O.; CARVALHO, Joao C. M. de; PENNA, Thereza C. V.; PESSOA JR., Adalberto
Fonte: JOHN WILEY & SONS LTD Publicador: JOHN WILEY & SONS LTD
Tipo: Artigo de Revista Científica
Português
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45.86%
In biotechnology, endotoxin (LPS) removal from recombinant proteins is a critical and challenging step in the preparation of injectable therapeutics, as endotoxin is a natural component of bacterial expression systems widely used to manufacture therapeutic proteins. The viability of large-scale industrial production of recombinant biomolecules of pharmaceutical interest significantly depends on the separation and purification techniques used. The aim of this work was to evaluate the use of aqueous two-phase micellar system (ATPMS) for endotoxin removal from preparations containing recombinant proteins of pharmaceutical interest, such as green fluorescent protein (GFPuv). Partition assays were carried out initially using pure LPS, and afterwards in the presence of E. coli cell lysate. The ATPMS technology proved to be effective in GFPuv recovery, preferentially into the micelle-poor phase (K(GFPuv) < 1.00), and LPS removal into the micelle-rich phase (%REM(LPS) > 98.00%). Therefore, this system can be exploited as the first step for purification in biotechnology processes for removal of higher LPS concentrations. (C) 2010 American Institute of Chemical Engineers Biotechnol. Prog., 26: 1644-1653, 2010; Capes - Brazil; National Council for Scientific and Technological Development (CNPq - Brazil); State of Sao Paulo Research Support Foundation (Fapesp - Brazil)

Analysis of vaginal lactobacilli from healthy and infected Brazilian women

ARTINEZ, Rafael C. R. M.; FRANCESCHINI, Silvio A.; PATTA, Maristela C.; QUINTANA, Silvana M.; NUNE, Alvaro C.; MOREIRA, Jodo L. S.; ANUKARN, Kingsley C.; REID, Gregor; MARTINIS, Elaine C. P. De
Fonte: AMER SOC MICROBIOLOGY Publicador: AMER SOC MICROBIOLOGY
Tipo: Artigo de Revista Científica
Português
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45.79%
Culture-dependent PCR-amplified rRNA gene restriction analysis and culture-independent (PCR-denaturing gradient gel electrophoresis) methodologies were used to examine vaginal lactobacilli from Brazilian women who were healthy or had been diagnosed with vulvovaginal candidiasis (VVC) or bacterial vaginosis. Only Lactobacillus crispatus was detected accordingly by both methods, and H2O2-producing lactobacilli were not associated with protection against VVC.

Plant-antivenom: Database of anti-venom medicinal plants

AMUI, Saulo Franca; PUGA, Renato David; SOARES, Andreimar Martins; GIULIATTI, Silvana
Fonte: UNIV CATOLICA DE VALPARAISO Publicador: UNIV CATOLICA DE VALPARAISO
Tipo: Artigo de Revista Científica
Português
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45.8%
Plant-antivenom is a computational Websystem about medicinal plants with anti-venom properties. The system consists of a database of these plants, including scientific publications on this subject and amino acid sequences of active principles from venomous animals. The system relates these data allowing their integration through different search applications. For the development of the system, the first surveys were conducted in scientific literature, allowing the creation of a publication database in a library for reading and user interaction. Then, classes of categories were created, allowing the use of tags and the organization of content. This database on medicinal plants has information such as family, species, isolated compounds, activity, inhibited animal venoms, among others. Provision is made for submission of new information by registered users, by the use of wiki tools. Content submitted is released in accordance to permission rules defined by the system. The database on biological venom protein amino acid sequences was structured from the essential information from National Center for Biotechnology Information (NCBI). Plant-antivenom`s interface is simple, contributing to a fast and functional access to the system and the integration of different data registered on it. Plant-antivenom system is available on the Internet at http://gbi.fmrp.usp.br/plantantivenom.; Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP); Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq); Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)

Wide Dispersal and Possible Multiple Origins of Low-Copy-Number Plasmids in Rickettsia Species Associated with Blood-Feeding Arthropods

BALDRIDGE, Gerald D.; BURKHARDT, Nicole Y.; LABRUNA, Marcelo B.; PACHECO, Richard C.; PADDOCK, Christopher D.; WILLIAMSON, Philip C.; BILLINGSLEY, Peggy M.; FELSHEIM, Roderick F.; KURTTI, Timothy J.; MUNDERLOH, Ulrike G.
Fonte: AMER SOC MICROBIOLOGY Publicador: AMER SOC MICROBIOLOGY
Tipo: Artigo de Revista Científica
Português
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45.79%
Plasmids are mobile genetic elements of bacteria that can impart important adaptive traits, such as increased virulence or antibiotic resistance. We report the existence of plasmids in Rickettsia (Rickettsiales; Rickettsiaceae) species, including Rickettsia akari, ""Candidatus Rickettsia amblyommii,"" R. bellii, R. rhipicephali, and REIS, the rickettsial endosymbiont of Ixodes scapularis. All of the rickettsiae were isolated from humans or North and South American ticks. R. parkeri isolates from both continents did not possess plasmids. We have now demonstrated plasmids in nearly all Rickettsia species that we have surveyed from three continents, which represent three of the four major proposed phylogenetic groups associated with blood-feeding arthropods. Gel-based evidence consistent with the existence of multiple plasmids in some species was confirmed by cloning plasmids with very different sequences from each of two ""Ca. Rickettsia amblyommii"" isolates. Phylogenetic analysis of rickettsial ParA plasmid partitioning proteins indicated multiple parA gene origins and plasmid incompatibility groups, consistent with possible multiple plasmid origins. Phylogenetic analysis of potentially host-adaptive rickettsial small heat shock proteins showed that hsp2 genes were plasmid specific and that hsp1 genes...

Characterization of the Phenol Monooxygenase Gene from Chromobacterium violaceum: Potential Use for Phenol Biodegradation

PERPETUO, Elen Aquino; MARQUES, Regina Celia Pereira; MENDES, Maria Anita; LIMA, Wanessa Cristina de; MENCK, Carlos Frederico Martins; NASCIMENTO, Claudio Augusto Oller do
Fonte: KOREAN SOC BIOTECHNOLOGY & BIOENGINEERING Publicador: KOREAN SOC BIOTECHNOLOGY & BIOENGINEERING
Tipo: Artigo de Revista Científica
Português
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45.8%
In this work, the biodegradation mechanism of phenol and sub products (such as catechol and hydroquinone) in Chromobacterium violaceum was investigated by cloning and molecular characterization of a phenol monooxygenase gene in Escherichia coli. This gene (Cvmp) is very similar (74 and 59% of similarity and identity, respectively) to the ortholog from Ralstonia eutropha, bacteria capable of utilizing phenol as the sole carbon source. The phenol biodegradation ability of E. coli recombinant strains was tested by cell-growth in a minimal medium containing phenol as the sole source of carbon and release of intermediary metabolites (catechol and hydroquinone). Interestingly, during the growth of these strains on phenol, catechol, and hydroquinone accumulated transiently in the medium. These metabolites were further analyzed by HPLC. These results indicated that phenol can be initially orto or para hydroxylated to produce cathecol or hydroquinone, respectively, followed by meta-cleavage of aromatic rings. To verify this information, the metabolites obtained from HPLC were submitted to LC/MS to confirm their chemical structure, thereby indicating that the recombinant strains utilize two different routes simultaneously, leading to different ring-fission substrates for the metabolism of phenol. (C) KSBB; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); CNPq (Brasilia...

Purification, and Biochemical and Biophysical Characterization of Cellobiohydrolase I from Trichoderma harzianum IOC 3844

COLUSSI, Francieli; SERPA, Viviane; DELABONA, Priscila da Silva; MANZINE, Livia Regina; VOLTATODIO, Maria Luiza; ALVES, Renata; MELLO, Bruno Luan; PEREIRA JR., Nei; FARINAS, Cristiane Sanches; GOLUBEV, Alexander M.; SANTOS, Maria Auxiliadora Morim; POLIKA
Fonte: KOREAN SOC MICROBIOLOGY & BIOTECHNOLOGY Publicador: KOREAN SOC MICROBIOLOGY & BIOTECHNOLOGY
Tipo: Artigo de Revista Científica
Português
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45.9%
Because of its elevated cellulolytic activity, the filamentous fungus Trichoderma harzianum has a considerable potential in biomass hydrolysis applications. Trichoderma harzianum cellobiohydrolase I (ThCBHI), an exoglucanase, is an important enzyme in the process of cellulose degradation. Here, we report an easy single-step ion-exchange chromatographic method for purification of ThCBHI and its initial biophysical and biochemical characterization. The ThCBHI produced by induction with microcrystalline cellulose under submerged fermentation was purified on DEAE-Sephadex A-50 media and its identity was confirmed by mass spectrometry. The ThCBHI biochemical characterization showed that the protein has a molecular mass of 66 kDa and pi of 5.23. As confirmed by small-angle X-ray scattering (SAXS), both full-length ThCBHI and its catalytic core domain (CCD) obtained by digestion with papain are monomeric in solution. Secondary structure analysis of ThCBHI by circular dichroism revealed alpha-helices and beta-strands contents in the 28% and 38% range, respectively. The intrinsic fluorescence emission maximum of 337 nm was accounted for as different degrees of exposure of ThCBHI tryptophan residues to water. Moreover, ThCBHI displayed maximum activity at pH 5.0 and temperature of 50 degrees C with specific activities against Avicel and p-nitrophenyl-beta-D-cellobioside of 1.25 U/mg and 1.53 U/mg...

Production of Fructooligosaccharides by Aspergillus phoenicis Biofilm on Polyethylene as Inert Support

Aziani, Guilherme; Terenzi, Hector Francisco; Jorge, Joao Atilio; Guimarães, Luis Henrique Souza
Fonte: FACULTY FOOD TECHNOLOGY BIOTECHNOLOGY; ZAGREB Publicador: FACULTY FOOD TECHNOLOGY BIOTECHNOLOGY; ZAGREB
Tipo: Artigo de Revista Científica
Português
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Aspergillus phoenicis biofilms on polyethylene as inert support were used to produce fructooligosaccharides (FOS) in media containing 25% (m/V) of sucrose as a carbon source. The maximum production of total FOS (122 mg/mL), with 68% of 1-kestose and 32% of nystose, was obtained in Khanna medium maintained at 30 degrees C for 48 h under orbital agitation (100 rpm). At high concentrations of sucrose (30%, m/V), the recovery of FOS was higher than that observed at a low concentration (5%, m/V). High levels of FOS (242 mg/mL) were also recovered when using the biofilm in sodium acetate buffer with high sucrose concentration (50%, m/V) for 10 h. When the dried biofilm was reused in a fresh culture medium, there was a recovery of approx. 13.7% of total FOS after 72 h of cultivation at 30 C, and 10% corresponded to 1-kestose. The biofilm morphology, analyzed by scanning electron microscope, revealed a noncompact mycelium structure, with unfilled spaces and channels present among the hyphae. The results obtained in this study show that A. phoenicis biofilms may find application for FOS production in a single-step fermentation process, which is cost-effective in terms of reusability, downstream processing and efficiency.; Foundation for Research Support from Sao Paulo State (FAPESP)...

Effect of Feed Strategy on Methane Production and Performance of an AnSBBR Treating Effluent from Biodiesel Production

Lovato, Giovanna; Bezerra, Roberto A.; Rodrigues, Jose A. D.; Ratusznei, Suzana M.; Zaiat, Marcelo
Fonte: HUMANA PRESS INC; TOTOWA Publicador: HUMANA PRESS INC; TOTOWA
Tipo: Artigo de Revista Científica
Português
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The aim of this work was to investigate the effect of different feeding times (2, 4 and 6 h) and applied volumetric organic loads (4.5, 6.0 and 7.5 gCOD L-1 day(-1)) on the performance of an anaerobic sequencing batch biofilm reactor (AnSBBR) treating effluent from biodiesel production. Polyurethane foam cubes were used as inert support in the reactor, and mixing was accomplished by recirculating the liquid phase. The effect of feeding time on reactor performance showed to be more pronounced at higher values of applied volumetric organic loads (AVOLs). Highest organic material removal efficiencies achieved at AVOL of 4.5 gCOD L-1 day(-1) were 87 % at 4-h feeding against 84 % at 2-h and 6-h feeding. At AVOL of 6.0 gCOD L-1 day(-1), highest organic material removal efficiencies achieved with 4-h and 6-h feeding were 84 %, against 71 % at 2-h feeding. At AVOL of 7.5 gCOD L-1 day(-1), organic material removal efficiency achieved with 4-h feeding was 77 %. Hence, longer feeding times favored minimization of total volatile acids concentration during the cycle as well as in the effluent, guaranteeing process stability and safety.; Fundacao de Amparo a Pesquisa do Estado de Sao PauloFAPESP (Sao Paulo, Brasil); Fundacao de Amparo a Pesquisa do Estado de Sao Paulo-FAPESP (Sao Paulo...

Lactobacillus sakei 2a and its Concentrated Acid Extract on Inhibition of Food-Borne Salmonella strains

Lafayette Neves Gelinski, Jane Mary; Baratto, Cesar Milton; Sacaratti, Dirceu; Gombossy de Melo Franco, Bernadette Dora
Fonte: DR M N KHAN; BHOPAL Publicador: DR M N KHAN; BHOPAL
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
45.81%
Lactic acid bacteria are used in food production to provide desirable organoleptic characteristics, and can also act as biopreservatives, controlling the growth of undesirable microorganisms. In this study, we examined the antimicrobial action of Lactobacillus sakei 2a and its concentrated acid extract against food-borne Salmonella spp. The extract was obtained by acid extraction from culture broth of L. sakei 2a and was designated extract 2a. We determined that extract 2a had significant activity (approximately 500 AU ml(-1)). We used different antimicrobial substances alone or in combination with extract 2a to evaluate the inhibitory activity of the various treatments on a pool of five Salmonella strains. The pathogen Listeria monocytogenes Scott A Cm-r Em(r) was used as an indicator strain of inhibitory activity. In summary, all antimicrobials substances that were tested showed an inhibitory effect against the growth of Salmonella, andthis action was enhanced in the presence of extract 2a. Moreover, among the treatments applied, the combination of extract 2a and 0.1% lactic acid exhibited the most potent inhibitory effect towards the pool of Salmonella strains. Our findings indicate that L. sakei 2a and extract 2a, especially in combination with other antimicrobials...

Gene expression during early somatic embryogenesis in Brazilian pine (Araucaria angustifolia (Bert) O. Ktze)

Schloegl, Paulo Sergio; Wendt dos Santos, Andre Luis; Vieira, Leila do Nascimento; Floh, Eny Iochevet Segal; Guerra, Miguel Pedro
Fonte: SPRINGER; DORDRECHT Publicador: SPRINGER; DORDRECHT
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
45.8%
Brazilian pine (Araucaria angustifolia (Bert) O. Ktze) is the only native conifer species with economic importance in Brazil. Recently, due to intensive exploitation Brazilian pine was included in the official list of endangered Brazilian plants, under the "vulnerable" category. Biotechnology tools like somatic embryogenesis (SE) are potentially useful for mass clonal propagation and ex situ conservation strategies of commercial and endangered plant species. In spite of that, numerous obstacles still hamper the full application of SE technology for a wider range of species, including Brazilian pine. To enhance somatic embryogenesis in Brazilian pine and to gain a better understanding of the molecular events associated with somatic embryo development, we analyzed the steady-state transcript levels of genes known to regulate somatic embryogenesis using semiquantitative reverse transcription polymerase chain reaction (sqRT-PCR). These genes included Argonaute (AaAGO), Cup-shaped cotyledon1 (AaCUC), wushel-related WOX (AaWOX), a S-locus lectin protein kinase (AaLecK), Scarecrow- like (AaSCR), Vicilin 7S (AaVIC), Leafy Cotyledon 1 (AaLEC), and a Reversible glycosylated polypeptide (AaRGP). Expression patterns of these selected genes were investigated in embryogenic cultures undergoing different stages of embryogenesis...