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One of the greatest challenges in the world is in the final disposal of plastics in order to reduce the effect of its polluting potential. Thus, the application of pyrolysis processes in generating products of interest such as fuel oils can be part of the solution. In addition to reducing greenhouse gas emissions to the atmosphere, oil can enter the supply chain after the cracking process in petrochemical industries. In this context, this work used statistical modeling of the response surface linked to the Normal Boundary Intersection algorithm, aiming at a higher yield of oil production and major selectivity of recycled polypropylene pyrolysis. From the analysis of the mechanisms proposed in the literature with the modeling and optimization in this work, it was possible, from a kaolin mass of 9.12 g and a heating ramp of 19.37°C/min, to obtain higher percentages of aviation kerosene as well as a satisfactory performance.

The present work presents the results of the production of vanillin-doped alginate biofilm. Alginate dressings are already a therapeutic reality, but they act only by maintaining the appropriate environment for healing. With the intention of improving their properties, the incorporation of vanillin was proposed due to its antioxidant and antimicrobial potential. Different biofilms were produced employing experiment planning through response surface analysis, which allowed determining the best region for a medium value of solubility and high degree of intumescence. This region refers to values above 0.07 g of CaCl2 and concentrations above 0.024 g of vanillin, triggering a solubility between 25% and 30% and a degree of intumescence above 100% and with fixed values of alginate (0.85 g). As for the optimization of the process, the Normal Boundary Intersection (NBI) method was able to analyze concave regions, predicting the optimal points and generating the Pareto chart with equidistant limits The antimicrobial test allowed the observation of antimicrobial activity against Escherichia coli and Pseudomonas aeruginosa microorganisms from the biofilms, as well as a solution of vanillin with calcium chloride and glycerol obtaining a halo of inhibition only in the presence of vanillin. Thermal analysis of thermogravimetry and differential exploratory calorimetry showed that the material has thermal stability, in the temperature range ideal for application as a biomaterial, for example as biocuratives.

Background: The retention of human milk nutrients in gastric tubes used to feed premature infants is a challenge to be overcome. Research Aims: To evaluate (1) the performance of six homogenizers (mixing processor, piston valve, ultrasonic bath, ultraturrax, stirring mixer, and ultrasound probe) for the fat retention reduction in gastric tubes; (2) the influence of the best homogenization conditions on the fatty acid and protein profiles of human milk; and (3) the cost/benefit ratio for the inclusion of homogenization as a new step in human milk processing. Methods: The influence of different levels and times of homogenization on reducing fat retention of human milk in probes was evaluated in this comparative prospective cross-sectional study. After homogenization, human milk flowed through a gavage and infusion pump apparatus used for feeding. Fat content was quantified before and after feeding. The techniques that reduced fat globule sizes and/or promoted a lower percentage of fat holding were evaluated for efficiency, variations in the fatty acid and protein profiles, and energy density and operating costs. Results: Homogenization led to a reduction in fat retention in feeding probes. The mixer processor and the ultrasound probe reduced fat retention by 99.23% (SD = 0.07) and 99.95% (SD = 0.02), respectively, and did not negatively influence fatty acid and protein profiles. The mixer processor demonstrated low energy density and low cost for human milk processing. Conclusion: Homogenization promoted reduced fat retention in the feed probe and could help maintain fat nutrients of human milk during enteral feeding.

Equilibrium data were obtained for aqueous two-phase systems composed of ionic liquid (IL) and two inorganic salts (dibasic potassium phosphate, K2HPO4, and tripotassium phosphate, K3PO4) at 298.15 K. The evaluated ionic liquids were 1-butyl-3-methylimidazolium methanesulfonate ([C4mim][CH3SO3]), 1-butyl-3-methylimidazolium chloride ([C4mim][Cl]), and 1-ethyl-3-methylimidazolium chloride ([C2mim][Cl]). Equilibrium curves of salt and ionic liquid were determined. Additionally, each curve was fitted into three mathematical models. The aqueous two-phase system composed of the IL [C2mim][Cl] required a lower mass fraction of IL and salt to form the systems than the other two systems studied in this work containing [C4mim][Cl] and [C4mim][CH3SO3]. Furthermore, the type of inorganic salts studied did not affect the equilibrium curves for the same ionic liquid.

A green and sustainable method has been developed to extract anthocyanins from broken black rice (BBR) using aqueous solutions of poly(ethylene glycol) (PEG). The effects of time, PEG concentration, temperature, BBR mass, and PEG molar mass were investigated using multivariate experimental designs. Time and temperature were not significant in the studied range and PEG 1500 was the most suitable. Under the optimized conditions, the anthocyanin concentration was 130.7 mg 100 g−1. The stability of the extract was higher at 25 °C and pH 5.0, with a reduction in absorbance (λmax = 455 nm) of only 7.14% after 60 days. The extract was applied in a colorless soap, and the color remained stable for 60 days (greater reduction in absorbance of 15.5% at 40 °C, λmax = 497 nm), indicating its potential for direct application in products of industrial interest. The method was also effective to extract anthocyanins from the husk and bran of black rice, with concentrations of 148.1 and 883.2 mg 100 g−1, respectively. In comparison with conventional methods for extracting anthocyanins, the proposed new technique offers the advantages of efficiency, simplicity and low cost, with the difference in extract concentration being obtained with methanol acidified with HCl of only 11%.

Whey is a cheese co-product with high protein content used in the food industry due to its techno-functional properties and nutritive value. This study aims to optimize the production of β-lactoglobulin (β-lg) nanostructures, to characterize their techno-functional properties and stability, and to apply them as a carrier of bioactive molecules. Box-Behnken planning was applied to determine the best conditions to obtain the β-lg nanostructure, which consists in treatment at 100 °C in NaCl 50 mmol·L-1 for 60 min. TEM analysis showed a fibril structure in the observed nanostructures. The nanostructured systems formed foam and emulsion with higher stability than the systems composed of the native protein. The results for encapsulation efficiency of bioactive compounds were 96.50%, 89.04%, 67.78%, and 36.39% for quercetin, rutin, naringin, and vitamin B2, respectively. Thus, β-lg nanostructure’s great capacity to encapsulate hydrophobic molecules was verified.

Currently, biomaterials have been used for the controlled release of drugs and hydrogels have been indicated as dressing components to treat superficial and deep wounds. The objective of this work, thus, was to incorporate the bacteriophage (antimicrobial) in polyvinyl alcohol (PVA) hydrogel for future application in skin infections. The bacteriophage (UFV-AREG1) was incorporated in PVA and (PVA-control and PVA-phage) were submitted to Swelling tests, Fourier Transform Infrared Spectroscopy (FTIR), DSC and TGA Thermal Analysis and antimicrobial effect on E. coli O157:H7. Swelling of the PVA-phage film (38%) was greater than the PVA-control (15%), which indicates in the PVA-phage (p

Nanostructures from conjugates of tara gum and α-lactalbumin were obtained via the heat-gelation process with pH adjustment. The conjugates were produced by Maillard reaction using the dry-heating method in lyophilized or spray-dried mixtures of TG and α-la and were characterized by browning index (BI) and percentage of free amino groups (% FAG). Nanostructured systems were characterized by dynamic light scattering, ζ-potential, circular dichroism, and intrinsic fluorescence to evaluate the structures. The most appropriate time of conjugation was 2 days. The spray-dried and lyophilized mixtures presented different values of BI and % FAG (p

Emulsifying properties of oil in water emulsions using quail egg white protein (Coturnix coturnix japonica) as an emulsifying agent were investigated using the conductivity technique. Changes in emulsion conductivity were recorded during and after homogenization. The results were interpreted in terms of properties related to the emulsifying activity and emulsion stability. The effect of salt concentrations (NaCl) of 0.0, 0.29, 0.59, 1.17, 1.76, and 2.34% (w v-1) when mixed with egg white concentrations of 0.50, 1.00 and 1.50% (w v-1) were studied using corn and soybean vegetable oils. Globally, one observed that emulsifying activity and emulsion stability increase with the enhancement of salt concentration. However, the increase of the egg white concentration did not present a significant influence on emulsifying activity, causing an increment only in emulsion stability. Emulsifying properties of oil in water emulsions using quail egg white protein (Coturnix coturnix japonica) as an emulsifying agent were investigated using the conductivity technique. Changes in emulsion conductivity were recorded during and after homogenization. The results were interpreted in terms of properties related to the emulsifying activity and emulsion stability. The effect of salt concentrations (NaCl) of 0.0, 0.29, 0.59, 1.17, 1.76, and 2.34% (w v-1) when mixed with egg white concentrations of 0.50, 1.00 and 1.50% (w v-1) were studied using corn and soybean vegetable oils. Globally, one observed that emulsifying activity and emulsion stability increase with the enhancement of salt concentration. However, the increase of the egg white concentration did not present a significant influence on emulsifying activity, causing an increment only in emulsion stability.

The indiscriminate use of antibiotics and the emergence of resistant microorganisms have become a major challenge for the food industry. The purpose of this work was to microencapsulate the bacteriophage UFV-AREG1 in a calcium alginate matrix using microfluidic devices and to study the viability and efficiency of retention. The microcapsules were added to gel of propylene glycol for use as an antimicrobial in the food industry. The technique showed the number of the phage encapsulation, yielding drops with an average 100-250 $\mu$m of diameter, 82.1 $\pm$ 2% retention efficiency and stability in the gel matrix for 21 days. The gel added to the microencapsulated phage showed efficiency (not detectable on the surface) in reducing bacterial contamination on the surface at a similar level to antimicrobial chemicals (alcohol 70%). Therefore, it was possible to microencapsulate bacteriophages in alginate-Ca and apply the microcapsules in gels for use as sanitizers in the food industry., Comment: 8 pages, 5 figures

The present study includes measurements of the phase composition, density, and refractive index of aqueous two-phase systems of poly(ethylene oxide) 1500 (PEO1500) + sodium thiosulfate + H2O at (28...

The phase compositions in liquid−liquid equilibria of aqueous two-phase systems (ATPS) composed of the poly(ethylene oxide)− poly(propylene oxide)−poly(ethylene oxide) (PEO−PPO−PEO) triblock copoly...

The partitioning of the whey protein lactoferrin, which is an iron transporter glycoprotein, in an aqueous two-phase system composed of poly(ethylene glycol) (PEG) and sodium citrate was evaluated. Equilibrium data at 25 °C were determined for each system studied using PEG with a molar mass of 1000 and 4000 g·mol1 at pH values of 5.5, 6.5, and 7.5. An increase in the molar mass of the polymer promoted the expansion of the two-phase region and caused the migration of the lactoferrin to the salt-rich bottom phase. An increase in pH also led to the expansion of the biphasic region. However, changing the pH over the tested range slightly affected protein partitioning. Lactoferrin recovery percentages greater than 94% were observed for all of the systems evaluated. The results indicated that lactoferrin can be successfully partitioned in an aqueous two-phase system formed of 14% (w/w) PEG and 10% (w/w) sodium citrate at pH 5.5 and 25 °C. The protein was concentrated 1000-fold in the salt-rich bottom phase in this system., Brazilian agencies FAPESB,CNPq, and FAPEMIG for their financial support

Phospholipases comprise a group of enzymes with applications in the thermal stability and emulsifying capacity of food formulations. In this work aqueous two-phase systems (ATPS) were used to extract phospholipase A 2 (PLA 2 ) from raw porcine pancreas and snake venom at 25 °C. PLA 2 was partitioned into ATPS composed of inorganic salts, water and polyethylene glycol. We determined the partition coefficient, recovery factor, purification factor, enzyme activity and emulsifying activity for the enzyme extracted with the different ATPS tested. The highest partition coefficient ( K p = 81.7) and the highest theoretical recovery percentage of PLA 2 in the top and bottom phases of the systems were obtained from the pancreas extract. The highest recovery percentage in the top phase was obtained in a system with PEG1500/Na 2 SO 4 /H 2 O. Pearson correlation analysis between the ATPS descriptor parameters and the recovery and partitioning parameters of PLA 2 showed significant, albeit small, correlation between molar mass and PEG phase volume. Furthermore, Principal Component Analysis showed that the best system for PLA 2 purification was with ATPS PEG1500/Na 2 SO 4 /H 2 O. In addition to preserving enzyme activity, the ATPS provided a high partition coefficient of PLA 2 (81.67%) and can be considered a viable technique for pre-purification of PLA 2 .

The study of protein interactions has generated great interest in the food industry. Therefore, research on new supramolecular structures shows promise. Supramolecular structures of the whey proteins {\alpha}-lactalbumin and glycomacropeptide were produced under varying heat treatments (25 to 75 {\deg}C) and acidic conditions (pH 3.5 to 6.5). Isothermal titration calorimetry experiments showed protein interactions and demonstrated that this is an enthalpically driven process. Supramolecular protein structures in aqueous solutions were characterized by circular dichroism and intrinsic fluorescence spectroscopy. Additional photon correlation spectroscopy experiments showed that the size distribution of the structures ranged from 4 to 3545 nm among the different conditions. At higher temperatures, lower pH increased particle size. The foamability of the supramolecular protein structures was evaluated. Analysis of variance and analysis of regression for foaming properties indicated that the two-factor interactions between pH and temperature exhibited a significant effect on the volume and stability of the foam., Comment: 9 pages, 5 figures

We investigated the extraction behavior of Cu(II) in the aqueous two-phase system (ATPS) formed by (L35+MgSO(4)+H(2)O) or (L35+(NH(4))(2)SO(4)+H(2)O) in the presence of the extracting agent 1-(2-pyridylazo)-2-naphthol (PAN). At pH=3 and a PAN concentration of 0.285 mmol kg(-1), both ATPS lead to the effective separation of Cu(II) from other metallic ions (Zn(II), Co(II), Ni(II) and Fe(III)). High separation factors range between 1000 and 10,000 were obtained for the extraction of Cu(II) and concomitant metallic ions. This ATPS was used for the extraction of Cu(II) from a leached ore concentrate with a extraction percentage of 90.4 ± 1.1%; other metals were mainly located in the bottom phase.

The effect of different ionic cosolutes (NaCl, Na$_2$SO$_4$, Li$_2$SO$_4$, NaSCN, Na$_2$[Fe(CN)5NO], and Na$_3$[Co(NO)$_6$]) on the interaction between sodium dodecyl sulfate (SDS) and poly(ethylene oxide) (PEO) was examined by small-angle X-ray scattering (SAXS) and isothermal titration calorimetric techniques. The critical aggregation concentration values (cac), the saturation concentration ($C_2$), the integral enthalpy change for aggregate formation ($\Delta H_{\mbox{agg}}$(int)) and the standard free energy change of micelle adsorption on the macromolecule chain ( $\Delta\Delta G_{\mbox{agg}}$) were derived from the calorimetric titration curves. In the presence of 1.00 mmol L$^{-1}$ cosolute, no changes in the parameters were observed when compared with those obtained for SDS-PEO interactions in pure water. For NaCl, Na$_2$SO$_4$, Li$_2$SO$_4$, and NaSCN at 10.0 and 100 mmol L$^{-1}$, the cosolute presence lowered cac, increased $C_2$, and the PEO-SDS aggregate became more stable. In the presence of Na$_2$[Fe(CN)5NO], the calorimetric titration curves changed drastically, showing a possible reduction in the PEO-SDS degree of interaction, possibility disrupting the formed nanostructure; however, the SAXS data confirmed, independent of the small energy observed, the presence of aggregates adsorbed on the polymer chain., Comment: 8 pages, 8 figures

The separation of Cd and Ni from Ni–Cd batteries using an aqueous two-phase system (ATPS) composed of copolymer L35, Li 2 SO 4 and water is investigated. The extraction behavior of these metals from the bottom phase (BP) to the upper phase (UP) of the ATPS is affected by the amount of added extractant (potassium iodide), tie-line length (TLL), mass ratio between the phases of the ATPS, leaching and dilution factor of the battery samples. Maximum extraction of Cd (99.2 ± 3.1)% and Ni (10.6 ± 0.4)% is obtained when the batteries are leached with HCl, under the following conditions: 62.53% (w/w) TLL, concentration of KI equal to 50.00 mmol kg −1 , mass ratio of the phases equal to 0.5 and a dilution factor of battery samples of 35. This novel methodology is efficient to separate the metals in question, with the advantage of being environmentally safe, since water is the main constituent of the ATPS, which is prepared with recyclable and biodegradable compounds.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior A análise exergética é uma ferramenta útil para avaliar a sustentabilidade de processos biotecnológicos. A aplicação da análise exergética como estratégia para o estudo e seleção das variáveis de processo é ainda pouco explorada no campo da biotecnologia. O conhecimento da exergia química padrão dos compostos envolvidos no sistema estudado é, normalmente, necessário para a análise. No entanto, o cálculo desta propriedade termodinâmica, em muitos casos, não é trivial, uma vez que ainda existe um número limitado de dados disponíveis na literatura para biocompostos. Diante disso, esta tese apresenta uma proposta para tomada de decisão de condições operacionais de biorreatores baseada em exergia. Inicialmente, foi realizada uma análise dos modelos de predição de exergia química padrão comumente aplicados em estudos de análise exergética. Esta análise foi dividida em três etapas. A primeira etapa teve como objetivo realizar um levantamento bibliográfico sobre as metodologias de predição das propriedades comumente empregadas para compostos de relevância biotecnológica. Com base no levantamento bibliográfico, foi identificado a carência de metodologias específicas para estimativa de exergia química padrão, levando ao uso de métodos alternativos de cálculo. Na segunda etapa, os modelos mais promissores de predição aplicados à biocompostos foram investigados mais detalhadamente. O desempenho da predição foi avaliado para modelos baseados no método de contribuição de grupo (CG) e para uma correlação semi-empírica que considera a combustão completa do composto em questão e banco de dados empíricos. Na terceira etapa, foram propostos modelos para predição de exergia química específica para compostos orgânicos puros e macromoléculas de relevância biotecnológica. Finalmente, foi realizada a análise exergética do processo de produção de xilitol como estratégia para a tomada de decisão de condições operacionais do biorreator mais produtivas e sustentáveis. Os resultados obtidos mostraram que o método baseado em CG apresentou melhor desempenho estatístico, apresentando um ajuste de R² igual a 0,98, erro absoluto médio de 0,56 MJ/kg e erro relativo médio de 4,21%. O modelo proposto para a estimativa da propriedade apresentou valores de R² e erro relativo médio de 99,41% e 2,30%, respectivamente. Com relação à análise exergética, a metodologia proposta mostrou ser uma ferramenta útil para o desenvolvimento de sistemas fermentativos para a produção de xilitol sob o ponto de sustentabilidade. Exergy analysis is a useful tool to assess the sustainability of biotechnological processes. The application of exergetic analysis as a strategy for the study and selection of process variables is still little explored in the field of biotechnology. Knowledge of the standard chemical exergy of the compounds involved in the studied system is usually necessary for the analysis. However, the calculation of this thermodynamic property, in many cases, is not trivial, since there is still a limited number of thermodynamic data available in the literature for biocompounds. Therefore, this thesis presents a proposal for decision-making on operating conditions of bioreactors based on exergy. Initially, an analysis of the standard chemical exergy prediction models commonly applied in exergetic analysis studies was performed. This analysis was divided into three stages. The first stage aimed to carry out a bibliographical survey on the property prediction methodologies commonly used for biotechnologically relevant compounds. In the second stage, the most promising prediction models applied to biocompounds were investigated in more detail. The prediction performance was evaluated for models based on the group contribution method and for a semi-empirical correlation that considers the complete combustion of the compound in question and empirical database. In the third step, hybrid models for prediction of specific chemical exergy for pure organic compounds and macromolecules of biotechnological relevance were proposed. Finally, an exergetic analysis of the xylitol production process was carried out as a strategy for decision-making on more productive and sustainable operating conditions for the bioreactor. The results obtained showed that the GC-based method presented better statistical performance, presenting an adjustment of equal to 0.98, mean absolute error of 0.56 MJ.kg−1 and mean relative error of 4.21%. The proposed model for property estimation showed values and mean relative error of 99.41% and 2.30%, respectively. Regarding the exergetic analysis, the proposed methodology proved to be a useful tool for the development of fermentative systems for the production of xylitol from the point of sustainability.