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1.
An Acad Bras Cienc ; 94(4): e20201438, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830020

RESUMO

This work aimed to compare the production of collagenolytic proteases produced by M. subtilissimus UCP1262 in submerged fermentation (SF) and solid-state fermentation (SSF) as well as extracting in aqueous two-phase system (ATPS). Collagenolytic protease production was performed in using MS-2 culture medium (SF) and soybean bran as substrate (SSF). Subsequently, the fermented liquid from both fermentations were used for the extraction of enzyme by ATPS, it was verified the influence of different variables from a factorial design 23. In SSF the highest protease and collagenolytic activities were achieved with 362.66 U/mL and 179.81 U/mL, respectively. When compared with SF (26.33 and 18.70 U/mL) higher values were obtained in the activities. The protease partitioning from SF and SSF in ATPS showed a similar profile showing higher affinity for the polymer rich phase. The highest value for the response variable purification factor (3.49) was obtained in the system using SSF. Thus, SSF shows promise as a bioprocess for extracellular production of collagenolytic proteases, using of soybean bran as substrate had used sustainable raw material, aiming application this possible enzyme in the treatment of burns and postoperative scarring.


Assuntos
Mucor , Peptídeo Hidrolases , Fermentação , Temperatura
2.
An Acad Bras Cienc ; 92(4): e20200521, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33331447

RESUMO

Copaiba oil is a natural product used by Amazonian populations and recognized for its medicinal properties because it has significant antimicrobial activity for several pathogenic microorganisms. The present work aimed to evaluate and characterize the effect of natural oil produced by copaiba - Copaifera multijuga against multiresistant isolates of bubaline mastitis. The nitrocefin test was performed with isolates of Staphylococcus aureus from bubaline mastitis, which were 100% positive for beta-lactamase enzyme detection. Minimum Bactericidal Concentration (MBC) of 25% to 3.12% was obtained for Enterococcus faecalis and Escherichia coli and 50% and 25% for S. aureus, but Klebsiella pneumoniae and Bacillus subtilis were resistant. MBC with 12.5% and 6.25% oil were obtained for most multiresistant bubaline mastitis isolates from the states of Pernambuco, Ceará, Bahia and Alagoas. The results demonstrated the great potential of using copaiba natural oil in the treatment of buffalo mastitis.


Assuntos
Anti-Infecciosos , Fabaceae , Mastite , Brasil , Feminino , Humanos , Mastite/tratamento farmacológico , Mastite/veterinária , Testes de Sensibilidade Microbiana , Staphylococcus aureus
3.
An Acad Bras Cienc ; 92(4): e20200882, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33295582

RESUMO

The industrial demand for proteolytic enzymes is stimulating the search for new enzyme sources. Fungal enzymes are preferred over bacterial enzymes, and more effective and easier to extract. The aim of this work was to evaluate the potential of protease production by solid state fermentation (SSF) of Mucor subtilissimus UCP 1262, evaluate different specific activities, purify and partially characterize the enzyme in terms of biochemical as to the optimal pH and temperature. Initially, the enzyme crude extract was screened for 3 different proteolytic activities, collagenolytic (161.4 U/mL), keratinolytic (39.6 U/mL) and fibrinolytic (26.1 U/mL) in addition to conventional proteinase activity. After ammonium sulfate precipitation, the active fractions with fibrinolytic activity were dialyzed in 15 mM Tris-HCl buffer, pH 8, loaded onto DEAE-Sephadex A50 ion-exchange column and gel filtrated through Superdex 75 HR10/300. The enzyme showed a fibrinolytic maximum activity at 40 C and pH 9,0. The purified enzyme showed activity against a chromogenic chymotrypsin substrate, SDS-PAGE showing a molecular mass of approximately 70 kDa and, the specific activity of 25.93 U/mg. These characteristics suggest that the enzyme could be and efficiently produced in a simple and low-cost way using Mucor subtilissimus UCP 1262 in SSF.


Assuntos
Mucor , Peptídeo Hidrolases , Quimotripsina , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Peso Molecular , Temperatura
4.
Pesqui. vet. bras ; 36(9): 805-810, set. 2016. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-829311

RESUMO

A mastite é uma inflamação na glândula mamária que pode acarretar perdas na produção e na qualidade do leite, gerando prejuízos econômicos para a pecuária leiteira. O tratamento é baseado na utilização de antibióticos, sendo, em muitos casos, ineficazes devido à resistência bacteriana já conhecida para esta doença. O objetivo deste trabalho foi selecionar linhagens de Streptomyces spp. produtoras de biocompostos com atividade antimicrobiana frente a isolados do gênero Staphylococcus multirresistentes de búfalas com mastite. Bem como, determinar os melhores parâmetros de produção, e avaliar a produção simultânea de ácido clavulânico. A seleção de Streptomyces spp. com capacidade de produzir compostos com atividade antimicrobiana foi realizada através da técnica bloco de gelose. Dentre as 30 espécies de Streptomyces spp. testadas, o micro-organismo Streptomyces parvulus DPUA 1573 apresentou melhores resultados, sendo capaz de inibir o crescimento de 7 isolados Staphylococcus spp. multirresistentes. Posteriormente, a espécie selecionada Streptomyces parvulus DPUA 1573 foi cultivada em diferentes condições pré-determinadas pelo planejamento fatorial 24, onde as variáveis independentes foram: concentração de soja (0,5; 1,0; 1,5%), glicose (0; 0,5; 1g/L), agitação (150; 200; 250rpm) e temperatura (28; 32; 37°C) e todos os ensaios do planejamento foram monitorados até 120 horas de cultivo. Todas as variáveis independentes influenciaram positivamente no crescimento celular, enquanto que para atividade antimicrobiana apenas as variáveis temperatura e agitação apresentaram efeitos significativos positivos. O líquido metabólito produzido por Streptomyces parvulus DPUA 1573 foi capaz de inibir o crescimento de sete Staphylococcus spp. multirresistentes. As melhores condições de cultivo para a produção de moléculas bioativas por este micro-organismo foi a 37?C, com 250rpm de agitação por período de 72 horas. Nos ensaios que apresentaram atividade antimicrobiana, foi avaliada a produção de ácido clavulânico ao longo do cultivo. A maior concentração de ácido clavulânico foi de 269,84g/L obtidas nas condições de 1,5% de farinha de soja em ausência de glicose no tempo de 96 horas. A linhagem Streptomyces parvulus DPUA 1573 foi eficiente contra Staphylococcus spp. multirresistentes isolados de mastite em búfalas, ainda apresentando concomitantemente produção de ácido clavulânico com o potencial uso farmacêutico.(AU)


Mastitis is an inflammation in one or more mammary glands which can lead to reduction in production and quality of milk causing economic losses to dairy farming. The use of antibiotics is the key for the treatment of this disease, but in many cases ineffective due to bacterial resistance already known for this condition. The aim of this study was to select strains of Streptomyces spp. producing biomolecules with antimicrobial activity against multidrug-resistant Staphylococcus isolated from buffaloes with mastitis, as well as to determine the best production parameters to the evaluation of simultaneous production of clavulanic acid. Thirty species of Streptomyces spp. were used to selecting the greatest producer spectrum of antimicrobial activity (agar block technique), with selection of Streptomyces parvulus DPUA 1573, and 7 multidrug-resistant Staphylococcus spp. sensitive to its biocompounds. The selected strain of Streptomyces parvulus DPUA 1573 was cultured in different conditions predetermined by the factorial design 24, where the independent variables were: soybean concentration (0.5, 1.0, 1.5%), glucose (0, 0.5, 1g/L), agitation (150, 200, 250rpm) and temperature (28, 32, 37°C); all the tests were monitored up to 120 hours of cultivation. All independent variables influenced positively the cell growth, while for antimicrobial activity only the variables temperature and agitation showed positive effects. The antimicrobial bio compounds showed activity against seven multidrug-resistant Staphylococcus spp under the conditions: temperature 37°C, agitation 250rpm, with 72 hours of production process. In the tests which showed antimicrobial activity, was also assessed the production of clavulanic acid along with the cultivation. The highest concentration of clavulanic acid was 269.84g/L obtained under the conditions of 1.5% of soybean flour and absence of glucose in 96 hours. The strain Streptomyces parvulus DPUA 1573 was effective against multidrug-resistant strains of Staphylococcus spp. of mastitis from buffaloes, still showing concomitantly production of clavulanic acid for pharmaceutical use.(AU)


Assuntos
Anti-Infecciosos/análise , Resistência Microbiana a Medicamentos , Mastite Bovina , Staphylococcus , Streptomyces/imunologia , Búfalos , Ácido Clavulânico/análise
5.
Biotechnol Prog ; 22(6): 1637-42, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17137312

RESUMO

The kinetic and thermodynamic properties of ascorbate oxidase (AO) activity and stability of a Cucurbita maxima extract were investigated. Activity tests performed at 25 degrees C using initial ascorbic acid concentration in the range 50-750 M allowed estimating the Michaelis constant for this substrate (Km = 126 microM) and the maximum initial rate of ascorbic acid oxidation (A0,max = 1.57 mM min-1). The main thermodynamic parameters of the enzyme reaction (DeltaH* = 10.3 kJ mol-1; DeltaG* = 87.2 kJ mol-1; DeltaS* = -258 J mol-1 K-1) were estimated through activity tests performed at 25-48 C. Within such a temperature range, no decrease in the initial reaction rate was detected. The long-term thermostability of the raw extract was then investigated by means of residual activity tests carried out at 10-70 degrees C, which allowed estimating the thermodynamic parameters of the irreversible enzyme inactivation as well (DeltaH*D = 51.7 kJ mol-1; DeltaG*D = 103 kJ mol-1; S*D = -160 J mol-1 K-1). Taking into account the specific rate of AO inactivation determined at different temperatures, we also estimated the enzyme half-life (1047 min at 10 degrees C and 21.2 min at 70 degrees C) and predicted the integral activity of a continuous system using this enzyme preparation. This work should be considered as a preliminary attempt to characterize the AO activity of a C. maxima extract before its concentration by liquid-liquid extraction techniques.


Assuntos
Ascorbato Oxidase/química , Cucurbita/enzimologia , Frutas/enzimologia , Extratos Vegetais/química , Ativação Enzimática , Estabilidade Enzimática , Cinética , Termodinâmica
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