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Id: biblio-1022849
Autor: Cabral Terrone, Cárol; Freitas, Caroline de; Fanchini Terrasan, César Rafael; Almeida, Alex Fernando de; Cano Carmona, Eleonora.
Título: Agroindustrial biomass for xylanase production by Penicillium chrysogenum: purification, biochemical properties and hydrolysis of hemicelluloses
Fonte: Electron. j. biotechnol;33:39-45, May. 2018. tab, graf, ilus.
Idioma: en.
Projeto: National Council of Technological and Scientific Development (CNPq); . São Paulo Research Foundation FAPESP/Brazil.
Resumo: Background: In this work, the xylanase production by Penicillium chrysogenum F-15 strain was investigated using agroindustrial biomass as substrate. The xylanase was purified, characterized and applied in hemicellulose hydrolysis. Results: The highest xylanase production was obtained when cultivation was carried out with sugar cane bagasse as carbon source, at pH 6.0 and 20°C, under static condition for 8 d. The enzyme was purified by a sequence of ion exchange and size exclusion chromatography, presenting final specific activity of 834.2 U·mg·prot-1. T he molecular mass of the purified enzyme estimated by SDS-PAGE was 22.1 kDa. The optimum activity was at pH 6.5 and 45°C. The enzyme was stable at 40°C with half-life of 35 min, and in the pH range from 4.5 to 10.0. The activity was increased in the presence of Mg+2 and Mn+2 and reducing agents such as DTT and ßmercaptoethanol, but it was reduced by Cu+2 and Pb+2 . The xylanase presented Km of 2.3 mM and Vmax of 731.8 U·mg·prot-1 with birchwood xylan as substrate. This xylanase presented differences in its properties when it was compared to the xylanases from other P. chrysogenum strains. Conclusion: The xylanase from P. chrysogenum F-15 showed lower enzymatic activity on commercial xylan than on hemicellulose from agroindustry biomass and its biochemistry characteristics, such as stability at 40°C and pH from 4.0 to 10.0, shows the potential of this enzyme for application in food, feed, pulp and paper industries and for bioethanol production.
Descritores: Penicillium chrysogenum/metabolismo
Polissacarídeos/metabolismo
Endo-1,4-beta-Xilanases/biossíntese
-Temperatura
Estabilidade Enzimática
Biomassa
Endo-1,4-beta-Xilanases/isolamento & purificação
Eletroforese em Gel de Poliacrilamida
Concentração de Íons de Hidrogênio
Hidrólise
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1045993
Autor: Zeeshan, Nadia; Naz, Saher; Naz, Shumaila; Afroz, Amber; Zahur, Muzna; Zia, Safia.
Título: Heterologous expression and enhanced production of ß-1, 4-glucanase of Bacillus halodurans C-125 in Escherichia coli
Fonte: Electron. j. biotechnol;34:29-36, july. 2018. ilus, tab, graf.
Idioma: en.
Projeto: Higher Education Commission, Pakistan (HEC).
Resumo: Background: Recombinant DNA technology enables us to produce proteins with desired properties and insubstantial amount for industrial applications. Endo-1, 4-ß-glucanases (Egl) is one of the major enzyme involved in degradation of cellulose, an important component of plant cell wall. The present study was aimed at enhancing the production of endo-1, 4-ß-glucanases (Egl) of Bacillus halodurans in Escherichia coli. Results: A putative Egl gene of Bacillus Halodurans was expressed in E. coli by cloning in pET 22b (+). On induction with isopropyl-b-D-1-thiogalactopyranoside, the enzyme expression reached upto ~20% of the cell protein producing 29.2 mg/liter culture. An increase in cell density to 12 in auto-inducing LB medium (absorbance at 600 nm) enhanced ß-glucanase production up to 5.4 fold. The molecular mass of the enzyme was determined to be 39 KDa, which is nearly the same as the calculated value. Protein sequence was analyzed by CDD, Pfam, I TASSER, COACH, PROCHECK Servers and putative amino acids involved in the formation of catalytic, substrate and metal binding domains were identified. Phylogenetic analysis of the ß-glucanases of B. halodurans was performed and position of Egl among other members of the genus Bacillus producing endo-glucanases was determined. Temperature and pH optima of the enzyme were found to be 60°C and 8.0, respectively, under the assay conditions. Conclusion: Production of endo-1, 4 ß-glucanase enzymes from B. halodurans increased several folds when cloned in pET vector and expressed in E. coli. To our knowledge, this is the first report of high-level expression and characterization of an endo-1, 4 ß-glucanases from B. halodurans.
Descritores: Bacillus/enzimologia
Celulases/biossíntese
-Temperatura
Estabilidade Enzimática
Expressão Gênica
Parede Celular/enzimologia
Reação em Cadeia da Polimerase
Clonagem Molecular
Celulases/isolamento & purificação
Celulases/metabolismo
Escherichia coli/metabolismo
Células Vegetais/enzimologia
Concentração de Íons de Hidrogênio
Hidrólise
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1045997
Autor: Su, Fang; Xu, Huarong; Yang, Na; Liu, Wei; Liu, Jianguo.
Título: Hydrolytic efficiency and isomerization during de-esterification of natural astaxanthin esters by saponification and enzymolysis
Fonte: Electron. j. biotechnol;34:37-42, july. 2018. tab, graf.
Idioma: en.
Projeto: The National Natural Science Foundation of China.
Resumo: Background: Astaxanthin from natural sources is typically esterified with fatty acids; hence, it must be hydrolyzed to remove esters before identification and quantification by conventional HPLC. Alkaline-catalyzed saponification and enzyme-catalyzed enzymolysis are the most commonly used de-esterification methods. However, information on the efficiency and isomerization during de-esterification of natural astaxanthin esters by these two methods remains scarce. Therefore, we conducted two HPLC-based experiments to determine which method is better for hydrolyzing astaxanthin esters. Results: To assess the effect of enzymolysis (0.67 U/mL cholesterol esterase, at 37°C) and saponification (0.021 M NaOH, at 5°C) conditions on free astaxanthin recovery and destruction or structural transformation of astaxanthin, we varied the total treatment time across a range of 195 min. The results showed that enzymolysis and saponification were complete in 60 min and 90 min, respectively. After complete hydrolysis, the maximum free astaxanthin recovery obtained by enzymolysis was 42.6% more than that obtained by saponification. The identification of by-products, semi-astacene and astacene, during the process of saponification also indicated that a more severe degradation of astaxanthin occurred during saponification. Moreover, the composition of astaxanthin isomers during saponification was similar to that of the isomers during enzymolysis between 30 min and 75 min (all-trans:9-cis:13-cis = 21:3:1, approximately) but dramatically changed after 90 min, whereas the composition in the enzymolysis treatment remained relatively stable throughout. Conclusion: Compared with saponification, enzymolysis with cholesterol esterase was recommended as a more accurate method for de-esterification of natural astaxanthin esters for further qualitative and quantitative HPLC analysis.
Descritores: Xantofilas/química
Ésteres/química
-Carotenoides
Xantofilas/metabolismo
Álcalis
Enzimas/metabolismo
Ésteres/metabolismo
Hidrólise
Isomerismo
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1254920
Autor: Nuñez, Suleivys M; Guzmán, Fanny; Valencia, Pedro; Almonacid, Sergio; Cárdenas, Constanza.
Título: Collagen as a source of bioactive peptides: a bioinformatics approach
Fonte: Electron. j. biotechnol;48:101-108, nov. 2020. tab, ilus.
Idioma: en.
Projeto: ANID PIA.
Resumo: BACKGROUND: Collagen is the most abundant protein in animals and can be obtained from residues of the food industry. Its hydrolysate has many desirable properties that make it suitable as an additive in foods and cosmetics, or as a component of scaffold materials to be used in biomedicine. RESULTS: We report here the characterization of type I collagen from five different sources, namely bovine, porcine, chicken, trout and salmon, as well as their hydrolysates by means of bioinformatics tools. As expected, the results showed that bovine and porcine collagen, as well as trout and salmon collagen, can be used interchangeably due to their high identity. This result is consistent with the evolution of proteins with highly identical sequences between related species. Also, 156 sequences were found as potential bioactive peptides, 126 from propeptide region and 30 from the central domain, according to the comparison with reported active sequences. CONCLUSIONS: Collagen analysis from a bioinformatic approach allowed us to classify collagen from 5 different animal sources, to establish its interchangeability as potential additive in diverse fields and also to determine the content of bioactive peptides from its in silico hydrolysis.
Descritores: Peptídeos
Colágeno/química
Biologia Computacional
-Hidrolisados de Proteína
Salmão
Suínos
Análise por Conglomerados
Colágeno Tipo I
Aditivos em Cosméticos
Aditivos Alimentares
Hidrólise
Limites: Animais
Bovinos
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1223238
Autor: Li, Xianjun; Wang, Junhuan; Wu, Wei; Jia, Yang; Fan, Shuanghu; Su Hlaing, Thet; Khokhar, Ibatsam; Yan, Yanchun.
Título: Cometabolic biodegradation of quizalofop-p-ethyl by Methylobacterium populi YC-XJ1 and identification of QPEH1 esterase
Fonte: Electron. j. biotechnol;46:38-49, jul. 2020. ilus, graf.
Idioma: en.
Projeto: National Natural Science Foundation of China; . Basic Research Fund of Chinese Academy of Agricultural Sciences.
Resumo: BACKGROUND: Quizalofop-p-ethyl (QPE), a unitary R configuration aromatic oxyphenoxypropionic acid ester (AOPP) herbicide, was widely used and had led to detrimental environmental effects. For finding the QPEdegrading bacteria and promoting the biodegradation of QPE, a series of studies were carried out. RESULTS: A QPE-degrading bacterial strain YC-XJ1 was isolated from desert soil and identified as Methylobacterium populi, which could degrade QPE with methanol by cometabolism. Ninety-seven percent of QPE (50 mg/L) could be degraded within 72 h under optimum biodegradation condition of 35°C and pH 8.0. The maximum degradation rate of QPE was 1.4 mg/L/h, and the strain YC-XJ1 exhibited some certain salinity tolerance. Two novel metabolites, 2-hydroxy-6-chloroquinoxaline and quinoxaline, were found by high-performance liquid chromatography/mass spectroscopy analysis. The metabolic pathway of QPE was predicted. The catalytic efficiency of strain YC-XJ1 toward different AOPPs herbicides in descending order was as follows: haloxyfop-pmethyl ≈ diclofop-methyl ≈ fluazifop-p-butyl N clodinafop-propargyl N cyhalofop-butyl N quizalofop-p-ethyl N fenoxaprop-p-ethyl N propaquizafop N quizalofop-p-tefuryl. The genome of strain YC-XJ1 was sequenced using a combination of PacBio RS II and Illumina platforms. According to the annotation result, one α/ß hydrolase gene was selected and named qpeh1, for which QPE-degrading function has obtained validation. Based on the phylogenetic analysis and multiple sequence alignment with other QPE-degrading esterases reported previously, the QPEH1 was clustered with esterase family V. CONCLUSION: M. populi YC-XJ1 could degrade QPE with a novel pathway, and the qpeh1 gene was identified as one of QPE-degrading esterase gene.
Descritores: Propionatos/metabolismo
Quinoxalinas/metabolismo
Methylobacterium/metabolismo
-Microbiologia do Solo
Biodegradação Ambiental
Methylobacterium/enzimologia
Methylobacterium/genética
Análise de Sequência de Proteína
Esterases/análise
Esterases/metabolismo
Herbicidas
Hidrolases/análise
Hidrolases/metabolismo
Hidrólise
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1180822
Autor: Mariano, Douglas O; Sciani, Juliana M; Antoniazzi, Marta M; Jared, Carlos; Conceição, Katia; Pimenta, Daniel C.
Título: Quantity - but not diversity - of secreted peptides and proteins increases with age in the tree frog Pithecopus nordestinus
Fonte: J. venom. anim. toxins incl. trop. dis;27:e20200105, 2021. tab, graf.
Idioma: en.
Projeto: CAPES; . FINEP; . FAPESP; . CNPq; . DCP; . MMA; . CJ.
Resumo: Amphibians inhabit the terrestrial environment, a conquest achieved after several evolutionary steps, which were still insufficient to make them completely independent of the aquatic environment. These processes gave rise to many morphological and physiological changes, making their skin (and cutaneous secretion) rich in bioactive molecules. Among the tree frogs, the secretion is composed mainly of peptides; but alkaloids, proteins and steroids can also be found depending on the species. The most known class of biologically active molecules is the antimicrobial peptides (AMPs) that act against bacteria, fungi and protozoans. Although these molecules are well-studied among the hylids, AMPs ontogeny remains unknown. Therefore, we performed peptidomic and proteomic analyses of Pithecopus nordestinus (formerly Phyllomedusa nordestina) in order to evaluate the peptide content in post-metamorphosed juveniles and adult individuals. Methods: Cutaneous secretion of both life stages of individuals was obtained and analyzed by LC-MS/MS after reduction and alkylation of disulfide bonds or reduction, alkylation and hydrolysis by trypsin. Results: Differences in the TIC profile of juveniles and adults in both treatments were observed. Moreover, the proteomic data revealed known proteins and peptides, with slight differences in the composition, according to the life stage and the treatment. AMPs were identified, and bradykinin-potentiating peptides were observed in trypsin-treated samples, which suggests a protein source of such peptide (cryptide). Conclusion: In general, skin secretion contents were similar between juveniles and adults, varying in quantity, indicating that the different stages of life are reflected in the number of molecules and not on their diversity.(AU)
Descritores: Peptídeos
Tripsina
Proteômica
Anfíbios
-Secreções Corporais
Hidrólise
Limites: Animais
Feminino
Responsável: BR68.1 - Biblioteca Virginie Buff D'Ápice


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Id: biblio-1041422
Autor: Paula-Mattiello, Shaiana; Oliveira, Sílvia Dias de; Medina-Silva, Renata.
Título: In vitro evaluation of hydrolytic enzyme activity and biofilm formation of Candida parapsilosis species complex from a nosocomial environment
Fonte: Rev. Soc. Bras. Med. Trop;50(4):558-561, July-Aug. 2017. tab, graf.
Idioma: en.
Resumo: Abstract INTRODUCTION: Candida parapsilosis complex species, frequently found in hospital environments, have gained importance as etiological agents of candidemia. METHODS: Candida parapsilosis complex isolates from a nosocomial environment were identified and their hydrolitic enzyme activity and ability to form biofilm were characterized. RESULTS: Twenty-two C. parapsilosis sensu stricto isolates produced proteinase and three produced phospholipase. Most Candida metapsilosis isolates produced proteinase and one also produced phospholipase. All 29 isolates formed biofilms. CONCLUSIONS: The nosocomial environment may act as a reservoir for C. parapsilosis complex isolates with phenotypic features that could possibly lead to nosocomial infections and health complications in hospital patients.
Descritores: Peptídeo Hidrolases/biossíntese
Fosfolipases/biossíntese
Candida/enzimologia
Biofilmes/crescimento & desenvolvimento
-Candida/isolamento & purificação
Candida/metabolismo
Ambiente de Instituições de Saúde
Hidrólise
Responsável: BR1.1 - BIREME


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Id: biblio-1132269
Autor: Paulova, Leona; Chmelik, Jan; Branska, Barbora; Patakova, Petra; Drahokoupil, Marek; Melzoch, Karel.
Título: Comparison of Lactic Acid Production by L. casei in Batch, Fed-batch and Continuous Cultivation, Testing the use of Feather Hydrolysate as a Complex Nitrogen Source
Fonte: Braz. arch. biol. technol;63:e20190151, 2020. tab, graf.
Idioma: en.
Projeto: MINISTRY OF EDUCATION, YOUTH AND SPORT OF THE CZECH REPUBLIC.
Resumo: Abstract A comprehensive comparison of the main fermentation parameters, productivity, yield and final L-lactic acid concentration, obtained through batch, fed-batch and continuous cultivations using Lactobacillus casei CCDM 198 and a model cultivation medium was carried out. Using this data, a pulse-feed fed-batch process was established for testing chicken feather hydrolysate as a replacement for all complex nitrogen sources (yeast and beef extracts and peptone) in the medium. As comparably high values of productivity (about 4.0 g/L/h) and yield (about 98 %) were reached under all cultivation conditions, the maximum final L-lactic acid concentration (116.5 g/L), as achieved through pulse-feed fed-batch fermentation, was chosen as the most important criterion for process selection. Fed-batch cultivation with chicken feather hydrolysate as both a complex nitrogen source and a neutralizing agent for maintaining constant culture pH yielded half the concentration of L-lactic acid compared to the model medium. We demonstrate here that chicken feather hydrolysate has potential for use in the production of L-lactic acid but its utilization requires further optimization
Descritores: Ácido Láctico/metabolismo
Fermentação
Lactobacillus casei/crescimento & desenvolvimento
-Biotecnologia/métodos
Cromatografia Líquida de Alta Pressão
Biomassa
Reatores Biológicos
Hidrólise
Limites: Animais
Tipo de Publ: Estudo Comparativo
Responsável: BR1.1 - BIREME


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Id: biblio-1146380
Autor: BELMONT-MONTEFUSCO, Enide Luciana; NACIF-MARÇAL, Lorena; ASSUNÇÃO, Enedina Nogueira de; HAMADA, Neusa; NUNES-SILVA, Carlos Gustavo.
Título: Cultivable cellulolytic fungi isolated from the gut of Amazonian aquatic insects
Fonte: Acta amaz;50(4):346-354, out. - dez. 2020.
Idioma: en.
Resumo: Fungos filamentosos tem sido alvo de estudos de bioprospecção devido à sua grande eficiencia em produzir enzimas extracelulares, as quais tem grande potencial para uso em bioindústrias. Neste estudo, fungos filamentosos foram isolados do intestino de larvas de insetos aquáticos da Amazônia, para avaliar sua atividade celulolítica. Foram coletadas 69 larvas de insetos aquáticos fragmentadores de três gêneros: Phylloicus (Trichoptera: Calamoceratidae), Triplectides (Trichoptera:Leptoceridae) e Stenochironomus (Diptera: Chironomidae) em dez igarapés de uma área protegida na Amazônia central brasileira. O crescimento dos fungos isolados foi feito em meio de cultura Ágar Batata Dextrose (BDA). Os isolados fúngicos foram transferidos para o meio sintético com Carboximetil celulose e utilizou-se vermelho Congo para determinar o índice enzimático. O halo de hidrólise, indicando a produção de celulases, foi observado em 175 isolados fúngicos (70% do total), dos quais 25 tiveram um índice enzimático ≥ 2,0 e pertencem a sete gêneros fúngicos. Os táxons fúngicos Cladosporium, Gliocephalotrichum, Penicillium, Pestalotiopsis, Talaromyces, Trichoderma e Umbelopsis foram isolados dos intestinos das larvas de Phylloicus, Triplectides e Stenochironomus e são tradicionalmente utilizados em aplicações biotecnológicas. Os resultados indicam um potencial celulolítco destes fungos associados ao intestino de insetos aquáticos amazônicos. (AU)
Descritores: Celulase
Fragmentadores
Ecossistema Amazônico
Hidrólise
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde


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Id: lil-437672
Autor: Alfaia, S. S.
Título: Caracterização e distribuição das formas do nitrogênio orgânico em três solos da Amazônia Central / Characterization and distribution of organic forms of nitrogen in three soils of Central Amazônia
Fonte: Acta amaz;36(2):135-140, abr.-jun.2006. ilus, tab.
Idioma: pt.
Resumo: As formas orgânicas do nitrogênio em solos são determinadas mediante a identificação e quantificação dos compostos orgânicos liberados, quando os solos são tratados com ácido a alta temperatura. Ainda não se conhecem na literatura trabalhos sobre a natureza química do N orgânico nos solos da Amazônia. O presente trabalho teve como objetivos identificar e quantificar a transformação do nitrogênio proveniente de fertilizantes marcados com 15N nas frações orgânicas nitrogenadas de três solos da Amazônia Central: dois solos de terra firme, classificados como Latossolo Amarelo e Podzólico Vermelho Amarelo e um solo de várzea, classificado como Glei Pouco Húmico. Foram utilizadas amostras de solos de um ensaio de adubação desenvolvido em condições de casa de vegetação, onde, após cultivo, procedeu-se o fracionamento do N orgânico do solo por meio da hidrólise ácida. Foram determinadas as seguintes frações: N-solúvel em ácido e destilado (NSAD), N-solúvel em ácido e não destilado (NSAnD) e N-não hidrolisado (NnH). Nos solos de terra firme, o N orgânico foi encontrado principalmente na forma de N solúvel em ácido e não destilado (NSAnD). Entre 63 a 66 por cento (Latossolo) e 69 a 73 por cento (podzólico) do 15N imobilizado no solo foram encontrados na fração NSAnD. Esses resultados demonstram a importância da imobilização microbiana do N nesses solos. No solo de várzea, ao contrário, houve pouca diferença entre os teores de 15N do fertilizante imobilizado nas frações NSAnD e NSAD. Entre 46 e 53 por cento do total de 15N imobilizado foram encontrados na fração NSAnD, enquanto que 42 a 52 por cento ficaram na fração NSAD. Nesse solo, a presença de argila tipo 2:1 pode ter contribuído para o alto estoque de 15N orgânico incorporado na fração NSAD, devido à fixação de íons NH4+.

The organic N forms in soil are determined by identification and quantification of organic compounds released by acid hydrolysis. There are no available data on the chemical nature of organic N in the Amazon soils. The objective of this study was to identify and quantify the transformation of 15N-labeled nitrogen fertilizers to different organic nitrogen fractions in three soils of Central Amazonia: an Oxisol, an Ultisol and a Low-Humic Gley (LHG). The soils were sampled after cultivation in greenhouse experiment. The chemical fractionation of soil organic nitrogen, as acid-hydrolysable and distillable N (NSAD), acid-hydrolysable non-distillable N (NSAnD) and non-hydrolysable N (NnH), was performed. In the Oxisol and Ultisol, 63 to 66 percent and 69 to 73 percent, respectively, of fertilizer N applied was incorporated in the NSAnD fraction. This suggests that N immobilization of microbial origin is important in these soils. In the LHG, there was equal immobilization in both NSAnD and NSAD fractions: 46 to 53 percent of N applied was immobilized in NSAnD, while 42 to 53 percent was immobilized in NSAD. In this soil, the presence of 2:1 type clays probably contributed to the high stock of 15N incorporated in the NSAD fraction, due to fixation of NH4+.
Descritores: Fertilizantes
Hidrólise
Imobilização
Nitrogênio
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde



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