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One of the main environmental problems presented by the textile industry is the generation of effluents containing synthetic dyes. Because of that, studies have been carried out in order to remove or degrade the dyes present in wastewater and thus, the adsorption process in polymeric matrices has been highlighted due to its low cost and high efficiency in bioremediation. In this context, it was verified the potential of biodegradation of the anthraquinone C. I. Reactive Blue 4 HFG textile dye (Dianativo®) by water kefir grains, as well as the application of the insoluble exopolysaccharide produced by the grains as an adsorbent of the dye, evaluating the effect of pH and initial concentration of dyes in the reduction of staining in a model system. The grains and their insoluble polysaccharide matrix were presented as capable of decolourizing dye solutions under the evaluated conditions, reducing the dye concentration in the solution by up to 92%.

Orientador: Hélia Harumi Sato Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: A transglutaminase catalisa a formação de ligações cruzadas entre grupos ?-amino de resíduos de lisina e o grupo ?-carboxiamida de resíduos de glutamina de proteínas. Esta enzima pode ser usada para unir diferentes proteínas e melhorar suas propriedades funcionais. A transglutaminase obtida de micro-organismos por processos fermentativos apresenta vantagens em relação à enzima obtida de plantas e tecidos animais para as aplicações industriais. Neste trabalho, foram estudados os efeitos de diferentes subprodutos ou resíduos agroindustriais no meio de cultivo para a fermentação submersa de Streptomyces sp. CBMAI-837, visando o aumento da atividade e da produtividade da enzima. Entre os substratos proteicos avaliados, o uso de 2,5% (m:v) de farelo de algodão ou de 2,5% (m:v) de farelo de soja no meio de cultivo resultou no aumento da atividade enzimática de 1,2 U.mL-1 (214%) e 1,0 U.mL-1 (182%), respectivamente, em relação ao valor obtido pela fermentação do micro-organismo em meio de cultivo contendo 2,5% de farinha de soja (0,57 U.mL-1). Em relação às fontes de carbono principais avaliadas, a adição de 2,0% de glicerol ou de 12% de melaço de cana de açúcar permitiu o aumento da atividade de transglutaminase em 0,94 U.mL-1 (167%) e 0,88 U.mL-1 (157%), respectivamente. Foi verificado que a adição de 1% de quitina nativa no meio de cultivo favoreceu a produção da enzima elevando a atividade de transglutaminase em 181% em relação ao meio de cultivo sem quitina. Os efeitos da aplicação da TGase de Streptomyces sp. CBMAI-837 em massa de farinha de trigo mole e na fabricação de pães foram avaliados e os resultados foram comparados com a atuação de uma TGase comercial (BioBond) formulada para aplicação em cereais. De forma geral, as duas enzimas avaliadas apresentaram o mesmo efeito sobre a massa quanto ao aumento da resistência à extensão, a redução da máxima extensão da massa e a redução da pegajosidade da massa. Efeito antagônico foi observado na hidrofobicidade de superfície das proteínas da massa sendo que este parâmetro foi reduzido pela adição da TGase de Streptomyces sp. CBMAI-837 e foi elevado pela enzima comercial. A adição de TGase na preparação da massa de farinha de trigo mole resultou em aumento da massa molecular das proteínas, indicantivo da formação de ligações cruzadas entre proteínas. A aplicação da transglutaminase de Streptomyces sp. CBMAI-837 em massa de pão de farinha de trigo mole promoveu a redução do volume do pão em 9% e o aumento da firmeza em 32%. O aumento da quantidade de solvente adicionado na massa de 53% para 56% permitiu o aumento do volume dos pães, no entanto, com pouca diferença dos parâmetros de textura em relação ao controle para a TGase comercial BioBond e para a TGase de Streptomyces sp. CBMAI-837 Abstract: Transglutaminase catalyzes the cross-linking reaction between a ?-carboxyamide of a glutamine residue from a peptide bond and the ?-amino group of a lysine. TGase can bind different proteins and improve their functional properties. The microbial transglutaminase shows advantages over the enzyme extracted from plants and mammals. In the present study, the effect of different industrial wastes and byproducts in the culture medium during the submerged fermentation of Streptomyces sp. CBMAI-837 was studied aiming to increase the enzyme activity and yield. Amongst the substrates with high protein content, the use of 2,5% of cottonseed meal or 2,5% of soybean meal in the culture medium increased the transglutaminase activity to 1.2 U.mL-1 (214%) and 1.0 U.mL-1 (182%), respectively, as compared to the results obtained using 2,5% of soybean flour. With regard to the main carbon sources, both 2% glycerol and 12% sugar cane molasses increased the transglutaminase activity to 0.94 U.mL-1 (167%) and 0.88 U.mL-1 (157%), respectively. It was observed that the addition of 1% of chitin on culture medium increased the transglutaminase activity by 181% as compared to the results obtained without the addition of chitin. The effects of the TGase from Streptomyces sp. CBMAI - 837 on soft wheat flour dough and on the manufacture of bread were evaluated, and the results were compared with the performance of a commercial TGase (BioBond) formulated for specific applications in cereal products. In general, both enzymes had the same effect on the rheological properties of the doughs, increasing the resistance to extension, reducing the maximum extension and reducing stickiness of the dough. The surface hydrophobicity of the protein dough was reduced by the addition of TGase from Streptomyces sp. CBMAI 837 but increased by the addition of the commercial enzyme. In general the analysis of the protein structure indicated an agglomeration of the proteins causing an increase in molecular weight. The application of transglutaminase from Streptomyces sp. CBMAI-837 in the formulation of bread loaves decreased the bread volume by 9% and increased firmness by 32%. Increasing the amount of solvent added to the dough from 53% to 56% increased the volume of the loaves, but resulted in little difference in the texture profiles of the loaves made with the addition of the commercial BioBond and Streptomyces sp. CBMAI ¿ 837 TGases, in relation to the control Doutorado Ciência de Alimentos Doutora em Ciência de Alimentos

This study reports the use of statistical mixture design as a tool for the simultaneous production of lipase, CMCase, α-amylase, and β-glucosidase by Aspergillus niger under solid-state fermentation. Wheat bran, soybean meal, cottonseed meal, and orange peel were used as substrates, either individually or combined in different formulations, to study their synergistic or antagonistic effects on production of the enzymes. The highest lipase (323 U g-1) and CMCase (10 U g-1) activities were detected after 48 h, while the maximum activities of α-amylase (18 U g-1) and β-glucosidase (15 U g-1) occurred at 72 and 96 h, respectively. Considering the substrate formulation, the ternary mixture of wheat bran (1/3), soybean meal (1/3), and cottonseed meal (1/3) was the most versatile, showing production of CMCase (>5 U g-1) and α-amylase (>8 U g-1) at 24 h, lipase (>320 U g-1) at 72 h, and β-glucosidase (>10 U g-1) at 48 h.

This study aimed to evaluate the substrate formulation using different agroindustrial wastes (wheat bran, soybean meal, cottonseed meal and orange peel) as a tool to purpose a versatile system for protease production by Aspergillus niger LBA 02 under solid state fermentation. The results showed interesting synergistic and antagonistic effects between the agroindustrial wastes during the protease production. The highest protease activity was found using the medium containing wheat bran (0.50) and soybean meal (0.50), reaching 262.78 U g−1 after 48 h fermentation. The most prominent synergetic effects were observed on fermentations performed using the medium composed by the four agroindustrial wastes in equal proportions at 48 and 72 h fermentation, reaching increases of 33.7%, 7.6%, 30.8% and 581.7% and 11.6%, 131.4%, 69.5% and 547.0%, respectively, in protease production as compared to the individual substrates. From these results was also possible to establish the use of at least three different culture media formulations with a maximum protease production above 260 U g−1, making it a versatile and efficient system for protease production and that can be easily applicable to other groups of enzymes.

This study reports the application of experimental mixture design as a tool to evaluate the effects of different formulations of media cultivation in invertase production by Aspergillus niger LBA 02 under solid state fermentation (SSF) using wheat bran, soybean meal, cottonseed meal and orange peel as agro-industrial waste substrates. Invertase production was correlated with the physical–chemical parameters of the agro-industrial wastes; it was shown that protein and ash content as well as high apparent density positively influences invertase production. Synergistic effects between the agro-industrial wastes were observed during the fermentation process; however, in most cases, soybean meal presented the highest positive effects on invertase production. After 48 h of fermentation, the formulation containing wheat bran, cottonseed meal and orange peel in equal proportions presented an interesting synergistic effect, reaching predicted values of enzyme activity higher than 100 μg−1. At 72 h of fermentation, the mixture of wheat bran, soybean meal and cottonseed meal in equal proportions reached predicted values higher than 140 μg−1. A statistical tool demonstrated an efficient strategy for enhancing enzyme production and evaluating synergistic effects between agro-industrial wastes from various sources. Furthermore, this process can also be applied in studies regarding waste prices, availability and profitability because this work presented alternatives for the formulation of media cultivation containing different agro-industrial wastes and the effects on enzyme production.

Agroindustrial wastes, such as wheat bran, soybean meal, cottonseed meal and orange peel, were used individually or in mixtures as fermentation feedstock for l -asparaginase production from Aspergillus niger LBA 02 under solid-state fermentation using a simplex centroid mixture design. At 24 h of fermentation, most of the interaction effects observed were antagonistic and the highest l -asparaginase activity was obtained with cottonseed meal as the feedstock. At 48 h of fermentation, synergistic effects were found for two binary formulations and one quaternary formulation and increase in the l -asparaginase activity ranged from 0.69 to 73.44 fold. At 72 h of fermentation, synergistic effects were also found for two binary and one quaternary formulation and increase ranged from 0.47 to 4.26 fold. At 96 h of fermentation, synergistic effects were found for four binary and one quaternary formulation and increase ranged from 0.44 to 17.84 fold. The enzyme production reached the highest value after 96 h of fermentation, and the optimum conditions predicted for l -asparaginase production were found to be a ternary mixture of wheat bran (1/3), soybean meal (1/3) and cottonseed meal (1/3) with increases of 71.53, 13.53 and 13.53 fold in l -asparaginase production as compared to the individual feedstocks, respectively. The predicted activity was 94.21 U g −1 , which showed no significant difference ( p l -asparaginase activity of 89.22 U g −1 . Therefore, mixtures contained wheat bran (1/3), soybean meal (1/3) and cottonseed meal (1/3) may be added to improve the l -asparaginase production with low cost.

Milk proteins modified by enzymatic hydrolysis have potential for optimizing functional properties. The most common method of improving the functional properties of milk proteins is to subject them to enzymatic hydrolysis. However, a limited number of studies correlated their results with the biochemical properties of the proteolytic enzymes to understand the mechanism of action by which the functional properties of the milk proteins are affected by the specificity of the proteases. In this review, the primary focus is the use of enzymatic hydrolysis of milk proteins as a tool for enhancing their functional properties, emphasizing protein solubility, gelation, and emulsion capacities. In particular, there is a discussion of the specificities of the proteolytic enzymes.

The network-forming attributes of gluten have been investigated for decades, but no study has comprehensively addressed the differences in gluten network evolution between strong and weak wheat types (hard and soft wheat). This study monitored changes in SDS protein extractability, SDS-accessible thiols, protein surface hydrophobicity, molecular weight distribution, and secondary structural features of proteins during mixing to bring out the molecular determinants of protein network formation in hard and soft wheat dough. Soft wheat flour and dough exhibited greater protein extractability and more accessible thiols than hard wheat flour and dough. The addition of the thiol-blocking agent N-ethylmaleimide (NEM) resulted in similar results for protein extractability and accessible thiols in hard and soft wheat samples. Soft wheat dough had greater protein surface hydrophobicity than hard wheat and exhibited a larger decrease in surface hydrophobicity in the presence of NEM. Formation of high-molecu...

Transglutaminase (TGase) can improve the functional characteristics of proteins by introducing covalent bonds inter- or intrachains. Temperature and pH interfere with the protein structure and the catalytic activity of enzymes. Because these three factors can act synergistically, TGase, citrate buffer, and temperature were evaluated for their effects on the rheological and chemical changes in low-protein wheat flour dough. Dough strength, measured by microextension test, significantly increased with increasing levels of TGase (8 U/g of protein), with changes in pH of the citrate buffer (pH 6.5), and by the effect of interaction between these factors. The same trend was observed in the size-exclusion HPLC measurements, indicating that these two parameters have the effect of increasing gluten protein aggregation. Temperature had a significant effect on dough extension, measured by microextension test. The changes in secondary structure of gluten protein were investigated by FTIR second-derivative s...

Transglutaminase catalyzes the cross-linking reaction between a glutamine residue and a free amine residue of proteins leading to the formation of protein aggregates. In this research, the effects of temperature, agitation, and aeration on the production of transglutaminase in a bench reactor by a newly isolated Streptomyces sp. from Brazilian soils were investigated using a factorial experimental design. The parameters evaluated influenced the enzyme production, and the data showed that the best conditions to enhance cell growth were different from those leading to enhanced transglutaminase production. Thus, a temperature and agitation shift strategy was adopted to increase transglutaminase productivity. The temperature and agitation were first set at 34 °C and 350 rpm, respectively, and after 24 h decreasing to 26 °C and 150 rpm until the end of fermentation. The transglutaminase activity obtained was 2.18 U/mL after 42 h of fermentation, which was twice than that obtained using a constant temperature and agitation fermentation strategy.

Os alimentos funcionais têm conquistado o mercado consumidor em virtude dos notáveis benefícios que promovem a saúde. No atual cenário de crescente interesse por bebidas alternativas ao leite, o objetivo da presente pesquisa consistiu na elaboração de bebidas láticas fermentadas funcionais a base de aveia, amêndoas, soja, castanha-do-brasil e arroz, empregando-se as culturas de Bifidobacterium BB-12, Lactobacillus acidophilus LA-5 e Streptococcus thermophilus. Os extratos vegetais, com e sem suplementação com sacarose foram fermentados a 37 °C por 12 horas. As bebidas elaboradas foram acondicionadas em garrafas de polietileno de alta densidade (PEAD) e estocados a 5°C na ausência de luz. Determinaram-se o pH, a acidez e a viabilidade das bactérias láticas após 1, 7, 15, 21 e 28 dias. Adicionalmente, determinou-se a composição centesimal das bebidas formuladas. Os valores de pH medidos no início e ao término da fermentação dos extratos variaram de 6,45 a 7,07 e de 4,10 a 4,97, respectivamente. Os índices de acidez, expressos em percentagem de ácido lático, variaram entre 0,01 e 0,06 g/100 mL no início e entre 0,02 e 0,33 g/100 mL ao final da fermentação. Os extratos fermentados apresentaram contagens de bactérias láticas acima dos valores mínimos estabelecidos pela legislação (106 UFC/mL) ao longo do estudo, para a maioria das amostras avaliadas. A suplementação com sacarose não interferiu na taxa de desenvolvimento das bactérias. Este estudo mostrou que a substituição total dos ingredientes lácteos por extratos vegetais hidrossolúveis é tecnologicamente viável, podendo disponibilizar ao consumidor uma bebida funcional sem conteúdo lácteo e com alta viabilidade probiótica. Functional foods have conquered the consumer market because of their remarkable health benefits. In the current scenario of growing market interest in alternative beverages to milk, the present study targeted the development of functional fermented lactic beverages formulated with oats, almonds, soybeans, Brazil chestnut and rice. Bifidobacterium BB-12, Lactobacillus acidophilus LA-5 and Streptococcus thermophiles were used as probiotic cultures. Regular and sucrose supplemented plant-based extracts were fermented at 37 °C for 12 h. The end product was filled into high density polyethylene (HDPE) bottles and stored at 5 °C in the dark. Measurements of pH, acidity and viability of lactic acid bacteria after 1, 7, 15, 21 and 28 days were carried out. Additionally, the centesimal composition was determined. The pH values measured in different plant-based beverages at the beginning of the fermentation ranged from 6.45 to 7.07, and from 4.10 to 4.97 at the end. The titratable acidity, expressed in lactic acid percentage, varied between 0.01 and 0.06 g/100 mL at the beginning, and between 0.02 and 0.33 g/100 mL after 28 days. The fermented extracts achieved lactic bacteria counts greater than the minimum threshold value set by Brazilian Regulation (106 CFU/mL) throughout the study, for most samples. Sucrose supplementation did not affect the lactic bacteria growth. The findings of this study showed that dairy ingredient\'s replacement by water-soluble plant extracts is technologically feasible. This may provide a functional beverage to consumers with dairy ingredients free and high probiotic viability as well.