19 research outputs found
Caracterização físico-química da amêndoa e do óleo de baru submetido à extração sólido- líquido com solventes alternativos / Physicochemical characterization of almond and baru oil submitted to solid-liquid extraction with alternative solvents
As fontes vegetais oleaginosas despertam grande interesse científico devido à possibilidade de enriquecer os alimentos e à aplicabilidade em cosméticos, combustíveis, entre outros. O óleo da amêndoa de baru apresenta grandes quantidades de proteínas, lipídeos de cadeia insaturada e elevado potencial antioxidante, com grandes concentrações de compostos fenólicos. Solventes como isopropanol e etanol vêm sendo investigados para substituir o hexano na extração de óleos, pois este é tóxico e proveniente de fonte não renovável. Assim, o presente estudo teve como objetivo estudar a variação dos efeitos de cada solvente na extração do óleo de baru, a fim de substituir o hexano. Os resultados mostraram que os óleos obtidos pelas extrações com isopropanol e etanol possuem semelhanças ao obtido através do hexano, sendo, portanto, viável a substituição deste nas indústrias.
The Process of Separating Bovine Serum Albumin Using Hydroxyapatite and Active Babassu Coal (Orbignya martiana)
Bovine serum albumin is one of the major serum proteins; it plays an important role as a result of its functional and nutritional properties which have bioactive peptides. Adsorption method was used to separate protein, which involves hydroxyapatite, synthetic hydroxyapatite, and active babassu coal. Initially, characterization was carried out using the zeta potential of the adsorbents. Kinetic pseudo-first-and pseudo-second-order models were applied. For isotherms, equilibrium data studies were carried out using the Langmuir and Freundlich models, in addition to determining the efficiency of adsorptive process. The results of the zeta potential showed loads ranging from +6.9 to −42.8 mV. The kinetic data were better represented in the pseudo-secondorder model with chemisorption characteristics. The adsorption capacity of the adsorbents decreased as pH increased, indicating that the electrostatic bonds and some functional groups of active babassu coal contributed to the reduction of adsorption, especially oxygen linked to carbon atoms. The value of pH 4.0 showed the best results of adsorption, being obtained as the maximum adsorption capacity ( ) and yield (%) (where = 87.95 mg g −1 and 74.2%; 68.26 mg g −1 and 68.6%; and 36.18 mg g −1 , 37.4%) of hydroxyapatite, synthetic hydroxyapatite, and active babassu coal, respectively
Tailoring the partitioning of proteins using ionic liquids as adjuvants in polymer-polymer aqueous biphasic systems
Aqueous biphasic systems (ABS) are promising for proteins purification; however, when dealing with samples comprising several proteins, the selectivity towards a target protein is difficult to achieve. In this work, the addition of ionic liquids (ILs) as adjuvants (5 and 10 wt%) in ABS composed of polyethyleneglycol (PEG) and Dextran was investigated to tailor proteins’ partitioning between the coexisting phases. The liquid-liquid phase diagrams were determined at 298 K, followed by partition studies of three proteins (bovine serum albumin (BSA), immunoglobulin G (IgG), and cytochrome C (Cyt C)). Partition coefficients of IgG and BSA indicate the preference of both proteins to the dextran-rich phase, whereas Cyt C has no preferential partitioning between the phases. The addition of chloride-based ILs as adjuvants allows to increase or decrease the partition coefficients, thus tailoring the proteins partitioning between the phases. BSA partitioning essentially depends on the IL content in each phase, whereas Cyt C and IgG partitioning is ruled by the ILs chemical structure and established interactions. Molecular docking was carried out to address the ILs effect on the proteins partitioning, supporting experimental observations, while identifying the specific interactions occurring. The partition of each protein in polymer-salt ABS with ILs as adjuvants was determined, demonstrating the higher tailoring ability of polymer-polymer ABS when adding ILs. Finally, the partition of each protein in presence of the remaining ones was determined, as well as the selectivity of the studied systems to separate each pair of proteins, paving the way for their use in liquid-liquid chromatography.publishe
The Process of Separating Bovine Serum Albumin Using Hydroxyapatite and Active Babassu Coal ( Orbignya martiana
Bovine serum albumin is one of the major serum proteins; it plays an important role as a result of its functional and nutritional properties which have bioactive peptides. Adsorption method was used to separate protein, which involves hydroxyapatite, synthetic hydroxyapatite, and active babassu coal. Initially, characterization was carried out using the zeta potential of the adsorbents. Kinetic pseudo-first- and pseudo-second-order models were applied. For isotherms, equilibrium data studies were carried out using the Langmuir and Freundlich models, in addition to determining the efficiency of adsorptive process. The results of the zeta potential showed loads ranging from +6.9 to −42.8 mV. The kinetic data were better represented in the pseudo-second-order model with chemisorption characteristics. The adsorption capacity of the adsorbents decreased as pH increased, indicating that the electrostatic bonds and some functional groups of active babassu coal contributed to the reduction of adsorption, especially oxygen linked to carbon atoms. The value of pH 4.0 showed the best results of adsorption, being obtained as the maximum adsorption capacity (qm) and yield (%) (where qm=87.95 mg g−1 and 74.2%; 68.26 mg g−1 and 68.6%; and 36.18 mg g−1, 37.4%) of hydroxyapatite, synthetic hydroxyapatite, and active babassu coal, respectively
Análise da capacidade de adsortiva do carvão da palha do café arábica utilizando o corante azul de metileno/ Analysis of the adsortive capacity of arabic coffee straw using blue methylene dye
O tratamento de efluentes da indústria têxtil tem sido alvo de estudo de muitos pesquisadores que procuram métodos mais eficientes e baratos para resolver o problema do despejo de corantes em rios e bacias hidrográficas. O presente trabalho estuda a eficiência da remoção do corante azul de metileno de uma solução aquosa, em diferentes pHs, com a utilização de carvão da palha do café arábica. Os resultados indicaram um aumento da capacidade adsortiva do carvão da palha do café arábica em pH mais básico (eficiência de remoção de azul de metileno de até 92,1%) indicando ser um material promissor para adsorção de corantes
<b>Optimization of protein extraction process from jackfruit seed flour by reverse micelle system
Separation of lysozyme, conalbumin and ovalbumin from the egg white: technological and thermodynamic aspects
Neste trabalho, estudou-se a integração dos processos de cromatografia de adsorção em leito expandido (ALE) e extração líquido-líquido por sistemas aquosos bifásicos (SAB) para a separação e purificação das proteínas da clara do ovo (ovalbumina, conalbumina e lisozima). A ALE foi empregada para a separação de duas frações protéicas da clara, uma rica em ovalbumina e outra contendo lisozima e conalbumina. Os SAB foram empregados com o objetivo de avaliar o comportamento da partição da lisozima e da conalbumina entre as fases superior e inferior, visando a separação destas proteínas da fração da ALE. A extração líquida por SAB pode ser usada para purificação de biocompostos em larga escala por possibilitar a partição seletiva com elevados rendimentos. Nestes ensaios foi analisada a influência do tipo de sal e da concentração do polímero, sobre a partição das proteínas, a fim de se obter o melhor sistema para a separação das mesmas. Os sistemas aquosos bifásicos foram compostos por polietileno glicol (PEG) de massa molar 1500 g/mol e diferentes sais (fosfato de potássio, citrato de sódio, sulfato de lítio e sulfato de sódio). Em adição, foram calculados parâmetros termodinâmicos (ΔtrH, ΔtrS, ΔtrG) de transferência das proteínas. Observou-se que a lisozima migrou predominantemente para a fase superior, rica em PEG, e a conalbumina concentrou-se preferencialmente na fase inferior, rica em sal. Entre os sistemas avaliados, o SAB PEG1500 (18 % em massa)-sulfato de sódio apresentou a maior porcentagem de recuperação teórica da lisozima na fase superior (aproximadamente 95,0 %). A maior porcentagem de recuperação da conalbumina na fase inferior foi obtida no SAB PEG1500 (18 % em massa)-citrato de sódio (aproximadamente 86,0 %). Este estudo mostrou que a integração de ALE e SAB pode ser usada para separação das proteínas ovalbumina, lisozima e conalbumina da clara do ovo.In this work, the separation of egg white proteins (lysozyme, conalbumina and ovalbumin) was studied integrating liquid- liquid extraction with aqueous two-phase systems (ATPS) and expanded bed adsorption (EBA). EBA was used to separate two egg white protein fractions, one rich in ovalbumin and other rich in conalbumina and lysozyme. The partition behavior of conalbumin and lysozyme between top and bottom phases of ATPS was investigated with the objective to separate these proteins from EBA fraction. This technique is an advisable purification process applied to large scale since it provides a selective partition with high yields. The influence of the type of salt (potassium phosphate, sodium citrate, lithium sulfate or sodium sulfate) and polymer (PEG 1500) phase concentrations (tie line length) in the system was studied in order to fit ratio of system to the separation. In addition, thermodynamic parameters (ΔtrH, ΔtrS, ΔtrG) were calculated and the results imply thermodynamic differences between partitioning of proteins. It was observed that the lysozyme partitioned preferentially to PEG phase and conalbumina to salt phase. Among the systems analyzed the ATPS PEG1500 (18 %)-sodium sulfate provided the best results for lysozyme extraction in the top phase (approximately 95,0 %) what demonstrates a good separation. The higher recovery of conalbumina in salt phase was obtained in the ATPS PEG1500 (18 %)-sodium citrate (approximately 86,0 %). This study showed that EBA and ATPS can be successfully used for recovery and initial purification of ovalbumin, lysozyme and conalbumin from egg white.Conselho Nacional de Desenvolvimento Científico e Tecnológic
ADSORPTION OF ALPHA-LACTALBUMIN FROM MILK WHEY ON HYDROXYAPATITE: EFFECT OF pH AND TEMPERATURE AND THERMODYNAMIC ANALYSIS
The nutritional and functional benefits offered by whey protein α-lactalbumin justify the great interest in its manufacture in large quantities at a high purity level. Hydroxyapatite is a calcium phosphate material able to adsorb proteins and can be synthesized at low production cost. Therefore, this work evaluated the adsorption of α-lactalbumin on hydroxyapatite using solid-liquid phase equilibrium data reported as adsorption isotherms. Van't Hoff's thermodynamics analysis showed that the adsorption process is entropically driven
Estudo da cinética de secagem da casca do maracujá (Passiflora edulis flavicarpa)/ Study of the drying kinetics of passion fruit (Passiflora edulis flavicarpa) rind
A atividade industrial de beneficiamento de polpas de frutas vem crescendo atualmente e com isso, possui destaque na geração de subprodutos, constituídos basicamente de cascas e sementes. Muitos destes subprodutos apresentam potencial para aproveitamento, no entanto ainda são pouco aproveitados e o seu descarte pode conduzir a impactos ambientais. Uma das alternativas de aproveitamento se dá por meio da secagem. Diante disso, estudou-se a viabilidade da secagem das cascas do maracujá por meio da avaliação do comportamento do produto durante a secagem em uma estufa com circulação de ar a 55 °C. O objetivo foi avaliar o comportamento desta etapa. De acordo com os resultados obtidos, pode-se afirmar que a partir de cinco horas a umidade em base seca não apresenta variações significativas