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1.
Nat Prod Res ; 36(17): 4475-4481, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34618614

RESUMO

Baru nuts (Dipteryx alata Vog.) are a native species from Brazil, rich in phenols and other antioxidants, with high socioeconomic value and possible pharmaceutical applications. Here we investigated baru nut ethanolic extract (BNEE) antioxidant and wound healing activities in human NCI-H441 and A549 lung epithelial cell lines for a possible use in conditions related to oxidative stress and wound healing impairments, such as chronic obstructive pulmonary disease (COPD). BNEE was characterised with high DPPH free radical scavenging activity and high total phenolics content, amongst them gallic acid, that was identified and quantified by HPLC. BNEE was not cytotoxic at concentrations studied, reduced the levels of reactive oxygen species before and during oxidative stress and increased wound healing in cell monolayers. These are the first steps to investigate the beneficial properties of baru in diseases related to oxidative stress and wound healing impairments such as COPD.


Assuntos
Dipteryx , Doença Pulmonar Obstrutiva Crônica , Antioxidantes/análise , Antioxidantes/farmacologia , Dipteryx/química , Células Epiteliais , Humanos , Pulmão , Nozes/química , Fenóis/análise , Fenóis/farmacologia , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Cicatrização
2.
Braz. J. Pharm. Sci. (Online) ; 58: e191042, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1394057

RESUMO

Abstract L-Asparaginase (L-ASNase) is a biopharmaceutical used for acute lymphoblastic leukaemia (ALL) treatment, dramatically increasing the patients' chance of cure. However, its production and distribution in developing countries were disrupted because of its low profitability, which caused great concern among patients. This study evaluates the feasibility of combining fractional precipitation and aqueous two-phase systems (ATPS) to purify L-ASNase from a low-grade product, commercially known as Acrylaway® L. The ATPS purification results were not particularly expressive compared to the two-step purification process composed of ethanol precipitation and gel filtration, which was able to recover the target molecule with a purification factor over 5 fold. Thus, we studied a purification process capable of manufacturing pharmaceutical grade L-ASNase from a commercially available low-grade raw material; however, improvements regarding its throughput must be achieved, and high purity is the first step to apply it as a new biopharmaceutical product. The proposed process could pose as a short-time solution to mitigate its shortage while a cost-effective production plant is being developed.


Assuntos
Asparaginase/isolamento & purificação , Precipitação Fracionada/métodos , Antineoplásicos/isolamento & purificação , Estudos de Viabilidade , Cromatografia em Gel , Análise Custo-Benefício
3.
Air Qual Atmos Health ; 14(12): 2091-2099, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745381

RESUMO

This work aims to obtain an artificial neural network to simulate hospitalizations for respiratory diseases influenced by pollutant gaseous such as CO, PM10, PM2.5, NO2, O3, and SO2 emitted from 2011 to 2017, in the city of São Paulo. The hospitalization costs were also be calculated. MLP and RBF neural networks have been tested by varying the number of neurons in the hidden layer and the type of equation of the output function. The following pollutants and its concentration range were collected considering the supervision of Alto Tiete station set, in several neighborhoods in the city of São Paulo, from in the period 2011 to 2017: 28-63 µg/m3 of PM2.5, 52-110 µg/m3 of PM10, 49-135 µg/m3 of O3, 0.8-2.6 ppm CO, 41-98 µg/m3 of NO2, and 3-16 µg/m3 of SO2. Results showed that a RBF neural network with 6 input neurons, 13 hidden layer neurons, and 1 output neuron, using BFGS algorithm and a Gaussian function to neuronal activation, was the best fitted to the experimental datasets. So, knowing the monthly concentration of gaseous pollutions was possible to predict the hospitalization of 1464 to 3483 ± 510 patients, with costs between 570,447 and 1,357,151 ± 198,171 USD per month. This way, it is possible to use this neural network to predict the costs of hospitalizing patients for respiratory diseases and to contribute to the decision-making of how much the government should spend on health care.

4.
Environ Technol ; 42(23): 3675-3687, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32148175

RESUMO

This paper presents the photocatalysis, adsorption, and photolysis of C.I. Reactive Blue 21 dye using synthesized zinc oxide nanoparticles. The density, mean particle diameter, surface area, and porosity of the catalyst were 5550 kg/m3, 1.19 × 10-7, 16,830 m2/kg, and 0.08, respectively. The impact of catalyst mass per volume of solution (0.2-1.0 kg/m3) was experimentally investigated in terms of the percentage of dye degradation. Due to the small catalyst porosity, adsorption contributed little to overall degradation. However, the photolysis of the dye was around 12.5%, which occurred predominantly between 0 and 5 min. In the second part of the present study, the photocatalytic degradation of C.I. Reactive Blue 21 was modelled mathematically based on the mass conservation law in the solution and catalyst. The model had two adjustable variables: the convection mass transfer coefficient and the photocatalytic reaction rate constant. The model was solved numerically using the finite difference method and was validated with the experimental data. The validated model was employed to examine the impact of catalyst size and initial pollutant concentration on the photocatalytic degradation.


Assuntos
Nanopartículas , Óxido de Zinco , Catálise , Metaloporfirinas , Fotólise
5.
Polymers (Basel) ; 11(10)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618858

RESUMO

Bromelain, a set of proteolytic enzymes potential pharmaceutical applications, was encapsulated in chitosan nanoparticles to enhance enzyme stability, and the effect of different chitosan sources was evaluated. Chitosan types (i.e., low molecular weight chitosan, chitosan oligosaccharide lactate, and chitosan from shrimp shells) produced nanoparticles with different physicochemical properties, however in all cases, particle size and zeta potential decreased, and polydispersity index increased after bromelain addition. Bromelain encapsulation was higher than 84% and 79% for protein content and enzymatic activity, respectively, with low molecular weight chitosan presenting the highest encapsulation efficiency. Nanoparticle suspension was also tested for accelerated stability and rheological behavior. For the chitosan-bromelain nanoparticles, an instability index below 0.3 was recorded and, in general, the loading of bromelain in chitosan nanoparticles decreased the cohesiveness of the final suspension.

6.
Braz. arch. biol. technol ; 62: e19180343, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1011533

RESUMO

Abstract Microalgae are aquatic unicellular microorganisms that can be found both in freshwater and marine systems; are capable of photosynthesis; and can grow as individual cells or associated in chains or small colonies. Microalgae cultivation has gained large momentum among researchers in the past decades due to their ability to produce value metabolites, remarkable photosynthetic efficiency, and versatile nature. The wide technological potential, and thus increasing amount of scattered knowledge, may become the very first barrier that a post graduating student, or any non-specialist reader, will face when introduced to the subject. In this review paper, we access the core aspects of microalgae technology, covering their main characteristics, and comprehensively presenting the main features of their various cultivation modes and biological activity from metabolites.


Assuntos
Produção Agrícola , Microalgas/crescimento & desenvolvimento , Compostos Fitoquímicos , Complexo de Proteínas do Centro de Reação Fotossintética
7.
Data Brief ; 18: 1224-1228, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29900298

RESUMO

The data presented in this article are related to the research article "Environmental and techno-economic considerations on biodiesel production from waste frying oil in São Paulo city" (Silva Filho et al., 2018) [1]. This article presents the variation of the concentration of waste frying oil (WFO) with the reaction time and temperature during the transesterification of WTOs collected in the residences and restaurants of the city of São Paulo. Then, the biodiesel samples were mixed with the S-10 diesel oil in order to obtain the B10, B20, B30, B40, B50, B75 and B100 blends, which were tested in a diesel engine and their power, fuel consumption and gas emissions (CO, CO2 and SO2) have been measured to verify their greenhouse effect and energy efficiency.

8.
J AOAC Int ; 101(5): 1461-1465, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29895343

RESUMO

BACKGROUND: The fruits acerola and red plum are known to be good sources of antioxidants, particularly vitamin C. Antioxidants are compounds that protect organisms from biomolecular damage, such as accelerated aging, caused by free radicals. OBJECTIVE: The objective of this study was to extract vitamin C from acerola and red plum, incorporate these extracts into different topical formulations, and evaluate the physicochemical stabilities of these formulations under stress conditions. METHODS: Vitamin C was extracted from acerola and red plum via dynamic maceration for 2 h at 50 ± 2°C and was quantified via HPLC. In vitro antioxidant activities were evaluated using DPPH assays. The extracts were then incorporated into emulsion and gel formulations in two types of packaging, and stability studies were carried out. RESULTS: Red plum and acerola extracts were orange and red and contained vitamin C concentrations of 2732.70 ± 93.01 mg/100 g and 2.60 ± 1.2 mg/100 g, respectively. In vitro antioxidant activity resulted in over 90.0% inhibition of free radicals at 0.01 mL/mL acerola extract and 0.1 mL/mL red plum extract. In the stability study, pH values decreased for both acerola formulations when stored in the oven or in transparent glass containers. Formulations containing red plum extract were stable under all conditions. Acerola extracts contained a higher concentration of vitamin C than red plum extracts. Both extracts possessed antioxidant activity, although the acerola-based formulation was unstable when stored at high temperatures or in transparent glass containers. HIGHLIGHTS: Extracts from red plum and acerola contained vitamin C; antioxidant activity of the extracts resulted in over 90.0% inhibition of free radicals. Formulations containing red plum were stable under all tested conditions, and formulations containing acerola were unstable when stored in the oven or in transparent glass containers.


Assuntos
Antioxidantes/análise , Ácido Ascórbico/análise , Cromatografia Líquida de Alta Pressão/métodos , Malpighiaceae/química , Extratos Vegetais/análise , Prunus domestica/química , Administração Tópica , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/farmacologia , Composição de Medicamentos , Estabilidade de Medicamentos , Emulsões/química , Radicais Livres/química , Frutas/química , Géis/química , Veículos Farmacêuticos/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia
9.
Planta Med ; 83(10): 870-876, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28196382

RESUMO

An ideal wound dressing ensures a moist environment around the wound area and absorbs exudates from the wound surface. Topical application of bromelain to incised wounds has been shown to reprogram the wound microenvironment to promote effective tissue repair. Combining the characteristics of hydrogels and bromelain is therefore of great interest. Herein, we describe the development of a hydrogel, formulated using alginate and Arabic gum, for bromelain loading and release. The hydrogel formulation was evaluated using response surface methodology, considering the pH value and the concentration of alginate and Arabic gum. Bromelain loading and release were evaluated based on passive diffusion. Differential scanning calorimetry and Fourier transform infrared spectroscopy were performed to confirm bromelain immobilization in the hydrogel. The final hydrogel formulation had a swelling ratio of 227 % and incorporated 19 % of bromelain from a bromelain solution. Bromelain immobilization in the hydrogel was the result of hydrogen bond formation and was optimal at 4 °C after 4 h of contact. This evidence suggests that bromelain entrapment into a hydrogel is a promising strategy for the development of wound dressings that support the debridement of burns and wounds.


Assuntos
Alginatos , Bromelaínas/administração & dosagem , Liberação Controlada de Fármacos , Goma Arábica , Bromelaínas/metabolismo , Composição de Medicamentos , Ácido Glucurônico , Ácidos Hexurônicos , Hidrogel de Polietilenoglicol-Dimetacrilato
10.
Biomed Res Int ; 2016: 8409183, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26925415

RESUMO

Given the importance of protease's worldwide market, the determination of optimum conditions and the development of a standard protocol are critical during selection of a reliable method to determine its bioactivity. This paper uses quality control theory to validate a modified version of a method proposed by Charney and Tomarelli in 1947. The results obtained showed that using azocasein substrate bromelain had its optimum at 45°C and pH 9 (Glycine-NaOH 100 mM). We also quantified the limit of detection (LoD) and limit of quantification (LoQ) in the above-mentioned optimum (0.072 and 0.494 mg·mL(-1) of azocasein, resp.) and a calibration curve that correlates optical density with the amount of substrate digested. In all analysed samples, we observed a significant decrease in response after storage (around 17%), which suggests its use must be immediately after preparation. Thus, the protocol presented in this paper offers a significant improvement, given that subjective definitions are commonly used in the literature and this simple mathematical approach makes it clear and concise.


Assuntos
Bromelaínas/química , Caseínas/química , Proteólise/efeitos dos fármacos , Bromelaínas/farmacologia , Caseínas/farmacologia , Concentração de Íons de Hidrogênio , Limite de Detecção , Especificidade por Substrato
11.
Biotechnol Prog ; 31(4): 937-45, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25919128

RESUMO

Bromelain is a set of proteolytic enzymes found in pineapple (Ananas comosus) tissues such as stem, fruit and leaves. Because of its proteolytic activity, bromelain has potential applications in the cosmetic, pharmaceutical, and food industries. The present study focused on the recovery of bromelain from pineapple peel by liquid-liquid extraction in aqueous two-phase micellar systems (ATPMS), using Triton X-114 (TX-114) and McIlvaine buffer, in the absence and presence of electrolytes CaCl2 and KI; the cloud points of the generated extraction systems were studied by plotting binodal curves. Based on the cloud points, three temperatures were selected for extraction: 30, 33, and 36°C for systems in the absence of salts; 40, 43, and 46°C in the presence of KI; 24, 27, and 30°C in the presence of CaCl2 . Total protein and enzymatic activities were analyzed to monitor bromelain. Employing the ATPMS chosen for extraction (0.5 M KI with 3% TX-114, at pH 6.0, at 40°C), the bromelain extract stability was assessed after incorporation into three cosmetic bases: an anhydrous gel, a cream, and a cream-gel formulation. The cream-gel formulation presented as the most appropriate base to convey bromelain, and its optimal storage conditions were found to be 4.0 ± 0.5°C. The selected ATPMS enabled the extraction of a biomolecule with high added value from waste lined-up in a cosmetic formulation, allowing for exploration of further cosmetic potential.


Assuntos
Ananas/enzimologia , Bromelaínas/química , Bromelaínas/isolamento & purificação , Fracionamento Químico/métodos , Cosméticos/química , Micelas , Biotecnologia
12.
Braz. arch. biol. technol ; 56(6): 971-979, Nov.-Dec. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-696944

RESUMO

The aim of this work was to isolate and purify bromelain extracted from the pineapple peel by ammonium sulfate precipitation (40-80%), followed by desalting and freeze-drying with a 75% activity recovery and 2.2 fold increased specific activity. Ion exchange chromatography on DEAE-Sepharose was able to separate the polysaccharides from the enzyme, which was recovered in the elution step, maintaining its enzymatic activity. The batch adsorption of bromelain was evaluated in terms of total protein and enzymatic activity using Langmuir and Langmuir-Freundlich models. Results showed that the process could be suitable for the recovery and purification of the enzyme, maintaining its specific activity.

13.
Braz. arch. biol. technol ; 55(5): 647-652, Sept.-Oct. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-651646

RESUMO

This study aimed to obtain the condition of maximum bromalein activity in different parts of pineapple plants produced in vitro, by micropropagation. The sStems and leaves of Pérola and Imperial cultivar plants were evaluated after three and eight months of in vitro cultivation in Murashige and Skoog medium without growth phytoregulator, macerated in potassium phosphate buffer at different pH values (5.7, 6.7 and 7.7). Total protein and proteolytic activity were determined in the samples after three- and eight-month cultivation periods. For both the cultivars, the best results were obtained at pH 5.7 in extraction media. Pérola cultivar, showed higher bromelain activity in the leaves cultivated in vitro for three months (0.0194U/mL) while in the Imperial cultivar, it was higher in the stem after eight months (0.0179 U/mL). Imperial cultivar showed higher bromelain activity than the Pérola's.

14.
Braz. arch. biol. technol ; 55(3): 465-470, May-June 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640198

RESUMO

The aim of this work was to study the production of e bromelain from the Ananas comosus L. Merril, by determining the process conditions using flat membranes. The production system modeling generated a hyperbolical curve and the optimization by response surfaces showed an influence of the transmembrane pressure higher than the pH influence. The cost of the production of bromelain from A. comosus was estimated 9 to 13 times lower than Sigma's retail sales price and 6.5 to 8.5 times lower than when this enzyme was obtained through a liquid-liquid extraction, which showed the economical feasibility of the process.

15.
Braz. arch. biol. technol ; 55(1): 7-19, Jan.-Feb. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-622676

RESUMO

This work aimed to study the partitioning of a lipase produced by Burkholderia cepacia in PEG/Phosphate aqueous two phase system (ATPS) and its characterization. Lipase was produced by B. cepacia strains in a fermenter. Enzyme partitioning occurred at pH 6.0 and 8.0, using PEG 1500 and 6000 on two tie lines. Metal ions, pH and temperature effects on enzyme activity were evaluated. Five milliliter of 7.5% olive oil emulsion with 2.5% gumarabic in 0.1M sodium phosphate buffer at pH 8.0 and 37ºC were used for the activity determinations. Results showed that crude stratum from B. cepacia was partitioned by PEG1500/phosphate ATPS at pH 6.0 or 8.0 for, which the partitioning coefficients were 108-and 209-folds. Lipase presented optimal activity conditions at 37ºC and pH 8.0; it showed pH-stability for 4 h of incubation at different pH values at 37ºC. Metal ions such as Mn2+ , Co2+, I-and Ca2+ sustained enzymatic activities; however, it was inhibited by the presence of Fe2+, Hg2+ and Al3+ . Km and Vmax values were 0.258 U/mg and 43.90 g/L, respectively. A molecular weight of 33 kDa and an isoelectric point at pH 5.0 were determined by SDS-PAGE and IFS electrophoresis, respectively.

16.
Pharm Dev Technol ; 17(4): 429-36, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21222512

RESUMO

Polymer film based on pH-dependent Eudragit FS 30 D acrylic polymer in association with arabinoxylane, a polysaccharide issued from gum psyllium, was produced by way of solvent casting. Physical-chemical characterization of the polymer film samples was performed by means of thermogravimetry (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Furthermore, water-equilibrium swelling index (I(s)) and weight loss of the films in KCl buffer solution of pH 1.2, in KH(2)PO(4) buffer solution of pH 5.0, or in KH(2)PO(4) buffer solution of pH 5.0 consisting of 4% enzyme Pectinex 3X-L (w/v) were also carried out for the film characterization. No chemical interactions between the Eudragit FS 30 D and the arabinoxylane polymer chains were evidenced, thus suggesting that the film-forming polymer structure was obtained from a physical mixture of both polymers. The arabinoxylane-loader films showed a more pronounced weight loss after their immersion in buffer solution containing enzyme Pectinex 3X-L. The introduction of the arabinoxylane makes the film more susceptible to undergo an enzymatic degradation. This meant that the enzyme-dependent propriety issued from the arabinoxylane has been imprinted into the film formulation. This type of polymer film is an interesting system for applications in colon-specific drug delivery system.


Assuntos
Colo/metabolismo , Sistemas de Liberação de Medicamentos , Ácidos Polimetacrílicos/química , Psyllium/química , Xilanos/química , Varredura Diferencial de Calorimetria , Preparações de Ação Retardada/química , Preparações de Ação Retardada/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Hidrolases/metabolismo , Ácidos Polimetacrílicos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Xilanos/metabolismo
17.
Braz. arch. biol. technol ; 54(1): 125-132, Jan.-Feb. 2011. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-576768

RESUMO

In this work, the thermodynamic equilibrium and applying of PEG4000/Phosphate ATPS on the purification of bromelain extracted from pineapple was studied. A rigorous study of the equilibrium curves and tie-line length from PEG4000/phosphate ATPS were done for the pH 6-11 at 25ºC. Results showed that there was augment in the PEG and salt contents with the high pH value from PEG4000/Phosphate ATPS and two-phase formation needed only increasing the PEG content. Two tie-line length at pH 11 from PEG4000/Phosphate ATPS were optimal condition for bromelain purification, one on composition of 14 percent PEG and 13 percent salt and other at 12.6 percent PEG and 12.2 percent salt, while a 25-62 folds of enzyme was found. SDS-PAGE electrophoreses had one band only, which showed that bromelain was purified. Optimum conditions of bromelain use were found at pH 7 and between 30-40ºC.

18.
Braz. arch. biol. technol ; 53(2): 455-463, Mar.-Apr. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-546578

RESUMO

A pulsed-cap microcolumn was used for bromelain extraction from pineapple juice by reversed micelles. The cationic micellar solution used BDBAC as the surfactant, isooctane as the solvent and hexanol as the co-solvent. In order to capture the dynamic behavior and the nonlinearities of the column, the operating conditions were modified in accordance with the central composite design for the experiment, using the ratio between the light phase flow rate and the total flow rate, and the time interval between pulses. The effects on the purification factor and on total protein yield were modeled via neural networks. The best topology was defined as 16-9-2, and the input layer was a moving window of the independent variables. The neural model successfully predicted both the purification factor and the total protein yield from historical data. At the optimal operating point, a purification factor of 4.96 and a productivity of 1.29 mL/min were obtained.


Uma micro-coluna com campânulas pulsantes foi utilizada para a extração de bromelina a partir de suco de abacaxi, usando micelas reversas. A solução catiônica micelar foi composta do surfactante BDBAC, do solvente iso-octano e do co-solvente hexanol. Seguindo um planejamento experimental, perturbações foram impostas à coluna de extração com o objetivo de capturar seu comportamento dinâmico e suas não-linearidades, usando a razão entre a vazão da fase leve e vazão total, e o intervalo de tempo entre os pulsos. Os efeitos das variáveis independentes sobre o fator de purificação e sobre o rendimento em proteínas totais foram modelados via redes neurais artificiais. A melhor topologia de rede obtida foi definida como 16-9-2, usando um esquema de janela móvel no tempo das variáveis independentes. O modelo neural obtido do histórico do processo se mostrou adequado para predizer simultaneamente o fator de purificação e o rendimento do processo em proteínas totais. No ponto ótimo de operação, foi encontrado um fator de purificação de 4.96, com produtividade de 1.29 mL/min.

19.
Braz. arch. biol. technol ; 52(5): 1225-1234, Sept.-Oct. 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-536399

RESUMO

The main aim of this study was to optimize the conditions for bromelain extraction by reversed micelles from pineapple juice (Ananas comosus). The purification was carried out in batch extraction and a micro-column with pulsed caps for continuous extraction. The cationic micellar solution was made of BDBAC as a surfactant, isooctane as a solvent and hexanol as a co-solvent. For the batch process, a purification factor of 3 times at the best values of surfactant agent, co-solvent and salt concentrations, pH of the back and forward extractions were, 100 mM, 10 percent v/v, 1 M, 3.5 and 8, respectively. For the continuous operation, independent variables optimal point was determined: ratio between light phase flow rate and total flow rate equal to 0.67 and 1 second for the time interval between the pulses. This optimal point led to a productivity of 1.29 mL/min and a purification factor of 4.96.


Este trabalho teve como objetivo principal otimizar as condições para extração da bromelina do suco do abacaxi (Ananas comosus) por micelas reversas. A purificação foi feita usando o processo de extração em batelada e contínuo, este último em uma micro-coluna de campânulas pulsantes. A solução micelar catiônica foi preparada com o surfactante BDBAC, i-octano como solvente e hexanol como co-solvente. Na extração em batelada encontrou-se um fator de purificação de 3 vezes, e seus melhores valores de concentração do agente surfactante, co-solvente e sal, de pH da re-extração e extração, foram respectivamente iguais a: 100 mM, 10 por cento v/v, 1 M, 3,5 e 8. Para a operação contínua, as variáveis independentes ótimas foram: 0,67 para a razão entre as taxas de fluxos da fase leve e a total e 1 s para o intervalo de tempo entre pulsos das campânulas. Este ponto ótimo leva a uma produtividade de 1,29 mL/min e a um fator de purificação igual a 4,96.

20.
Braz. arch. biol. technol ; 52(4): 991-1000, July/Aug. 2009. ilus
Artigo em Inglês | LILACS | ID: lil-525621

RESUMO

In this work the α and β-amylase enzymes were obtained from maize (Zea mays) malt and were biochemistry characterized. A germination study to obtain the maize malt with good amylase activity was made. The maize seeds were germinated in laboratory and the enzymatic activity was measured daily. Activity dependence to germination time were fitted to an exponential model (A=A0eµt), which showed that the behaviour of enzymatic activity in the germination process was similar to the growth of the microorganism. Its model could be applied to describe the mechanism of α-amylase production for each maize varieties and others cereals. Maize malt characterization showed that α and β-amylase had optimal pH between 4-6.5, optimal temperature 50 and 90ºC, and molecular weight of 67.4 and 47.5kDa, respectively. This work contributed with the advances in biotechnology generating of conditions for application of a new and of low price amylases source.


Neste trabalho as enzimas α e β-amilases foram obtidas de malte de milho e depois foram caracterizadas bioquimicamente. Um estudo da germinação foi feito para obtenção do malte com boa atividade amilásica. A germinação ocorreu em escala laboratorial e a atividade enzimática foi medida diariamente. Um modelo exponencial do tipo A=A0eµt foi ajustado a dependência do tempo de germinação com a atividade, mostrando que o comportamento da atividade enzimática no processo de germinação é semelhante ao crescimento de microorganismos. Este modelo pode ser aplicado para descrever o mecanismo de produção da α-amilase para cada variedade de milho e de outros cereais. A caracterização do malte de milho mostrou que as α e β-amilase têm pH ótimo entre 4,0-6,5, temperatura ótima de 50 e 90ºC, e massa molar de 67,4 e 47,5 kDa, respectivamente. Este trabalho contribuiu com os avanços da biotecnologia gerando condições de emprego de uma nova e barata fonte de amilases.

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