RESUMO
ß-glucosidase is an essential enzyme for the enzymatic hydrolysis of lignocellulosic biomass, as it catalyzes the final stage of cellulose breakdown, releasing glucose. This paper aims to produce ß-glucosidase from Saccharomyces cerevisiae and evaluate the enzymatic degradation of delignified sugarcane bagasse. S. cerevisiae was grown in yeast peptone dextrose medium. Partial purification of the enzyme was achieved through precipitating proteins with ethanol, and the optimal activity was measured by optimizing pH and temperature. The effects of ions, glucose tolerance, and heat treatment were evaluated. Delignified sugarcane bagasse was hydrolyzed by the enzyme. ß-glucosidase showed a specific activity of 14.0712 ± 0.0207 U mg-1. Partial purification showed 1.22-fold purification. The optimum pH and temperature were 6.24 and 54 °C, respectively. ß-glucosidase showed tolerance to glucose, with a relative activity of 71.27 ± 0.16%. Thermostability showed a relative activity of 58.84 ± 0.91% at 90 °C. The hydrolysis of delignified sugarcane bagasse showed a conversion rate of 87.97 ± 0.10% in the presence of Zn2+, an ion that promoted the highest increase in enzymatic activity. S. cerevisiae produced an extracellular ß-glucosidase with good stability at pH and temperatures conventionally applied in the hydrolysis of lignocellulosic biomass, showing viability for industrial application.
Assuntos
Saccharomyces cerevisiae , Saccharum , Celulose , Hidrólise , beta-Glucosidase , GlucoseRESUMO
The management of inflammatory states typically involves non-steroidal anti-inflammatory drugs (NSAIDs) and opiates. Understanding the mechanisms underlying the processing of nociceptive information from potential alternatives such as some polysaccharides may enable new and meaningful therapeutic approaches. In this study, α-D-mannan isolated from the Kluyveromyces marxianus cell wall produced antinociceptive effects in models of inflammatory pain (formalin and complete Freund's adjuvant tests). Furthermore, α-D-mannan reduced paw edema and interleukin-6 (IL-6) production after carrageenan-induced inflammation. The polysaccharide α-D-mannan was characterized by gas chromatography-mass spectrometry, methylation analysis, and spectroscopic techniques. Moreover, the Doehlert experimental design was applied to find the optimal conditions for biomass production, with the best conditions being 10.8 g/L and 117 h for the glucose concentration and the fermentation time, respectively. These results indicate that α-D-mannan from K. marxianus exerts anti-inflammatory and antinociceptive effects in mice, possibly via a mechanism dependent on the inhibition of IL-6 production.
Assuntos
Analgésicos , Interleucina-6 , Camundongos , Animais , Analgésicos/farmacologia , Analgésicos/química , Analgésicos/uso terapêutico , Mananas , Anti-Inflamatórios/farmacologia , PolissacarídeosRESUMO
Mannans has been attracted the interest in various sectors due to its promising applications. The low toxicity of mannans allows for their use in cosmetics, pharmaceutical, and biomedical industries. In this study, the α-D-mannan extraction conditions from Aureobasidium pullulans by alkaline extraction were optimized using a Box-Behnken design (BBD). The effect of temperature (°C), pH and extraction time (hours) on the yield of α-mannan was investigated. The conditions that produced the highest yield (26%) were a temperature of 92 °C, extraction time of 3 h and pH 13. In addition, the α-D-mannan structure was confirmed by methylation analysis, 1D and 2D NMR spectroscopic analysis, and GC-MS.
Assuntos
Mananas , Temperatura , Espectroscopia de Ressonância MagnéticaRESUMO
Guava juice is cloudy and viscous, which hinders filtration, decreases yield, and causes the loss of quality after its processing and during storage. This study aimed to evaluate enzymatic treatment effects using crude multi-enzymatic extracts (CME) obtained from Rhodotorula mucilaginosa, Rhodotorula orizycola, and Pseudozyma sp. produced by submerse fermentation in the extraction of juice guava. Mixtures of 100 ml of guava pulp and multi-enzymatic extracts proposed by Doehlert planning were incubated under constant agitation at 150 rpm and 50°C, and a Doehlert design was applied as a multivariate optimization strategy. The optimal conditions using the multi-enzymatic extract were: 0.4% (v/v) of CME for 131 min for the multi-enzymatic treatment using Pseudozyma sp.; 3.0% (v/v) of CME for 154 min using the R. mucilaginosa CME; and 5.0% (v/v) of CME for 90 min using R. oryzicola. The maximum viscosity reduction values for the juices treated with the CME of yeasts were 10.33%, 86.38%, and 13.33% for the juices treated with the CME of Pseudozyma sp., R. mucilaginosa, and R. orizycola, respectively. The physical-chemical properties were improved after treatment with CMEs, yielding a reduction of clarity, increase of total soluble solids and reducing sugars, and decreasing the acidity (pH) for all treatments with enzymatic extracts of all strains. The yeasts studied showed a potential for CME production to be applied to juice, improving the quality of the juice, and R. mucilaginosa was the most prominent yeast due to most significant reduction of viscosity in guava juice.
Assuntos
Psidium , Psidium/química , Frutas/química , Extratos Vegetais/químicaRESUMO
ß-Glucosidase is widely used in several industrial segments, among which we can highlight the pharmaceutical industry, beverages, biofuels, animal feed production, and the textile industry. The great applicability of this enzyme, associated with the high cost of its production, justifies the need to find ways to make its use economically viable on an industrial scale. Through enzyme immobilization, the biocatalyst can be reused more than once, without great impact on its catalytic activity, and higher operational and storage stabilities can be achieved as compared to the free form. Accordingly, this review brings information about different techniques and supports that have been studied in the immobilization of cellulases with a focus on ß-glucosidase, as well as the application of these immobilized systems to supplement commercial mixtures.
Assuntos
Enzimas Imobilizadas , beta-Glucosidase , Biocombustíveis , Estabilidade EnzimáticaRESUMO
The protease was produced extracellularly in submerged fermentation by the yeast Rhodotorula oryzicola using different sources of nitrogen and maximum activity (6.54 × 10-3 U/mg) was obtained in medium containing 2% casein (w/v). Purification of the protease by gel filtration chromatography resulted in a 3.07-fold increase of specific protease activity. The optimal pH and temperature for enzyme activity were 6.51 and 63.04 °C, respectively. Incubation in the presence of some salts enhanced enzyme activity, which peaked under 0.01 M BaCl2 . The enzyme retained about 90% of enzymatic activity at temperatures 50-60 °C. The commercially available enzyme carriers evaluated, silica gel, Celite 545, and chitosan effectively immobilized the protease. The enzyme immobilized in Celite 545 retained 73.53% of the initial activity after 15 reuse cycles. These results are quite promising for large-scale production and immobilization of protease from R. oryzicola, as the high operational stability of the immobilized enzyme lowers production costs in biotechnological applications that require high enzymatic activity and stability under high temperatures.
Assuntos
Peptídeo Hidrolases/metabolismo , Rhodotorula/enzimologia , Biotecnologia , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Concentração de Íons de Hidrogênio , Peptídeo Hidrolases/química , TemperaturaRESUMO
The current study aims to assess the kinetics of population growth of Rhodotorula oryzicola and the production of ß-1,3-glucanase (EC 3.2.1.39) enzyme by this yeast. It also aims to obtain the optimum conditions of ß-1,3-glucanase enzymatic activity by varying the pH as well as to study the enzyme thermostability. R. oryzicola population doubled within 12 hr. During this period, 9.26 generations were obtained, with 1 hr and 29 min of interval from one generation to the other, with specific growth rate (µ) of 0.15 (hr-1). The entire microorganism growth process was monitored during ß-1,3-glucanases production, and the maximum value was obtained in the stationary phase in the 48-hr fermentation period. pH and temperature optimum values were 4.7 and 96°C, respectively. The enzyme maintained 88% of its activity when submitted to the temperature of 90°C for an incubation period of 1 hr. The results show that the enzyme can be used in industrial processes that require high temperatures and acidic pH.
Assuntos
Glucana 1,3-beta-Glucosidase/metabolismo , Rhodotorula/enzimologia , Estabilidade Enzimática , Temperatura Alta , Concentração de Íons de Hidrogênio , Microbiologia Industrial , Cinética , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/metabolismo , Especificidade por SubstratoRESUMO
Tannase can be used in different industrial sectors such as in food (juices and wine) and pharmaceutical production (trimethoprim) because it catalyses the hydrolysis of hydrolysable tannins. The aim of the current study is to assess the tannase found in the crude extract of Saccharomyces cerevisiae CCMB 520, and to set its catalytic and thermodynamic properties. The enzyme was optimally active at pH 6.0 and temperature 30 °C. Tannase was activated by Na+, Ca2+, K+ at 5 × 10-3 mol/L. The half-life at 30 °C was 3465.7 min. The activation energy was 40.32 kJ/mol. The Gibbs free energy, enthalpy and entropy at 30 °C were 85.40, 48.10 and -0.12 kJ/mol K, respectively. Our results suggest that the tannase found in the crude extract of S. cerevisiae is an attractive enzyme for industrial applications, such as for beverage manufacturing and gallic acid production, due its catalytic and thermodynamic properties (heat-stable and resistant to metal ions).
Assuntos
Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/metabolismo , Saccharomyces cerevisiae/enzimologia , Catálise , Estabilidade Enzimática , Meia-Vida , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Temperatura , TermodinâmicaRESUMO
Endoglucanase production by Aspergillus oryzae ATCC 10124 cultivated in rice husks or peanut shells was optimized by experimental design as a function of humidity, time, and temperature. The optimum temperature for the endoglucanase activity was estimated by a univariate analysis (one factor at the time) as 50°C (rice husks) and 60°C (peanut shells), however, by a multivariate analysis (synergism of factors), it was determined a different temperature (56°C) for endoglucanase from peanut shells. For the optimum pH, values determined by univariate and multivariate analysis were 5 and 5.2 (rice husk) and 5 and 7.6 (peanut shells). In addition, the best half-lives were observed at 50°C as 22.8 hr (rice husks) and 7.3 hr (peanut shells), also, 80% of residual activities was obtained between 30 and 50°C for both substrates, and the pH stability was improved at 5-7 (rice hulls) and 6-9 (peanut shells). Both endoglucanases obtained presented different characteristics as a result of the versatility of fungi in different substrates.
Assuntos
Aspergillus oryzae/enzimologia , Celulase/metabolismo , Microbiologia Industrial/métodos , Arachis/metabolismo , Aspergillus oryzae/química , Aspergillus oryzae/metabolismo , Celulase/química , Estabilidade Enzimática , Fermentação , Análise Multivariada , Oryza/metabolismo , Resíduos Sólidos/análise , TemperaturaRESUMO
The aims of the current study are to assess the influence of polyethylene glycol (PEG) concentration, molar mass, pH, and citrate concentrations on aqueous biphasic systems based on 24 factorial designs, as well as to check their capacity to purify tannase secreted by Aspergillus tamarii URM 7115. Tannase was produced through submerged fermentation at 26°C for 67 h in Czapeck-Dox modified broth and added with yeast extract and tannic acid. The factorial design was followed to assess the influence of PEG molar mass (MPEG 600; 4,000 and 8,000 g/ mol), and PEG (CPEG 20.0; 22.0 and 24.0% w/w) and citrate concentrations (CCIT 15.0, 17.5, and 20.0%, w/w), as well as of pH (6.0, 7.0, and 8.0) on the response variables; moreover, partition coefficient (K), yield (Y), and purification factor (PF) were analyzed. The most suitable parameters to purify tannase secreted by A. tamarii URM 7115 through a biphasic system were 600 (g/mol) MPEG, 24% (w/w) CPEG, 15% (w/w) CCIT at pH 6.0 and they resulted in 6.33 enzyme partition, 131.25% yield, 19.80 purification factor and 195.08 selectivity. Tannase secreted by A. tamarii URM 7115 purified through aqueous biphasic systems composed of PEG/citrate can be used for industrial purposes, since it presents suitable purification factor and yield.