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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Functional properties of enzymically hydrolysed fish waste

Ahmad, Najat Hassan January 1990 (has links)
Enzymic hydrolysis of cod fish waste was investigated using two enzymes (trypsin and bromelain). A fish protein hydrolysate (FPH) powder and frozen flake hydrolysate were produced using a spray drier and an ice flake machine. Functional properties of the FPH were assessed with respect to the molecular weight (MW) spectrum. The characteristics of solubility and emulsification for the hydrolysate showed it to be suitable for use as a binder compared with egg albumin (EA) and soy bean isolate (ISB) for fish products. Fishburgers with improved texture, succulence and reasonable cooking losses were made successfully from cod fish mince incorporating a vegetable oil/water emulsion stabilised by FPH. Taste panels were carried out and overall acceptability of the fishburgers made from the FPH emulsion was better than fishburgers containing EA and ISB emulsions. Economic evaluation and specification of a pilot plant were done for both FPH powder and frozen flake hydrolysate production. This work strongly emphasises that FPH should only be used in fish products which need a good binder and where the flavour/taint problems of use in other products, e.g. beverages, pasta, will not arise.
2

Reciclagem de resíduos do processamento de tilápia (Oreochromis niloticus) visando obter hidrolisado proteico como coproduto / Tilapia (Oreochromis niloticus) processing residues recycling to obtain protein hydrolysates as coproduct

Lunelli, Taciana 08 October 2015 (has links)
O crescimento da produção e comercialização de pescado gera um aumento considerável na quantidade de resíduos. A escassez de reutilização e as formas incorretas de descarte tem sido preocupação constante das indústrias e dos pesquisadores, que buscam soluções para a melhor destinação dos mesmos. Buscando o conceito de empresa eco eficiente, são propostos tratamentos que levem à obtenção de coprodutos. A produção de \"farinha de peixe\" é a forma de aproveitamento do resíduo mais utilizada, porém apresenta baixo valor comercial. A elaboração de hidrolisados proteicos apresenta-se como uma alternativa de maior valor agregado. A clivagem proteica realizada por enzimas específicas pode gerar peptídeos biologicamente ativos, que apresentam propriedades funcionais e medicinais, bem como atividade antioxidante. O objetivo deste trabalho foi a elaboração e caracterização de hidrolisados proteicos de cabeças de tilápia (Oreochromis niloticus), a aferição da atividade antioxidante destes e sua relação com o tamanho de peptídeos, como forma de se obter e disponibilizar coprodutos, visando a sustentabilidade da cadeia produtiva desta espécie. O hidrolisado proteico de tilápia (HPT) foi obtido por hidrólise enzimática e empregando as enzimas Neutrase (Protemax NP-800), Papaína (Brauzyn-100) e Pepsina nos tempos 30, 60 e 120 minutos. O grau de hidrólise foi determinado através da metodologia com utilização do o-ftaldialdeído. A atividade antioxidante foi avaliada pelos ensaios do DPPH e ABTS+. O perfil de peptídeos foi avaliado através da separação por cromatografia em gel com coluna Superdex peptide. O grau de hidrólise para os tratamentos com a neutrase (30 min, 60 min, 120min) variou de 11,3% a 14,1%. No tratamento com a papaína (30 min, 60 min, 120 min) o grau de hidrólise foi superior ao observado com a enzima neutrase, apresentando variação de 21,14%a 25,28%. A variação para o tratamento com a pepsina (30 min, 60 min e 120 min) foi de 10,18% a 14,97% Todos os hidrolisados apresentaram propriedade antioxidante através da inibição de radicais livres, mesmo a concentrações baixas de hidrolisado. A inibição de 50% (EC50) dos radicais na metodologia de DPPH ocorreu com concentrações inferiores a 3mg/mL para todos os tratamentos, sendo a menor concentração 1,36 mg/mL (pepsina 120 min) e a maior 2,70 mg/mL (neutrase 30 min). Na metodologia de ABTS, concentrações superiores foram necessárias para a inibição de 50% dos radicais, porém ainda assim foram inferiores a 5%. A menor concentração foi 3,58 mg/mL (pepsina 120 min) e a maior foi de 4,49 mg/mL (neutrase 60 min). O tamanho das cadeias de peptídeos para a maioria dos tratamentos se situou entre cadeias de 1000 a 10000Da, sendo que o tratamento com pepsina promoveu porcentagem de peptídeos com maior peso molecular seguido pela neutrase. A papaína foi a enzima que promoveu maior clivagem de proteína e menores tamanhos de peptídeos, localizados na faixa de 100 a 1000 Da, valor relacionado ao seu maior grau de hidrólise. As propriedades observadas nos hidrolisados elaborados indicam que este pode ser um potencial suplemento alimentício devido ao seu elevado valor proteico, aditivos para conservação de alimentos e ainda aplicados na indústria farmacêutica. / The growth in production and marketing of fish generates a considerable increase in the amount of waste. The scarcity of re-used products and incorrect disposal forms has been a constant concern of industries and researchers who seek solutions for better allocation thereof. Seeking an efficient eco company concept, proposed treatments are leading to obtaining co-products. The production of \"fish meal\" with the residues is the most common use for the waste, but has a low commercial value. The preparation of protein hydrolysates is presented as an alternative with higher added value. The protein cleavage performed by specific enzymes can generate biologically active peptides which exhibit functional and medicinal properties as well as antioxidant activity. The objective of this work was the preparation and characterization of protein hydrolysates of tilapia (Oreochromis niloticus) , the measurement of antioxidant activity of these and its relation to the size of peptides as a way to obtain and provide co-products , aimed at the sustainability of the chain production of this species. The protein hydrolyzate of tilapia (HPT) was obtained by enzymatic hydrolysis and employing the enzyme Neutrase (Protemax NP- 800), Papain (Brauzyn - 100) and Pepsin at 30, 60 and 120 minutes. The degree of hydrolysis was determined using o- phthaldialdehyde . In the treatment with papain (30 min, 60 min, 120 min) the degree of hydrolysis was higher than that observed with Neutrase enzyme, showing variation of 21.14% to 25.28%. The variation for treatment with pepsin (30 min, 60 min and 120 min) was 10.18% and 14.97% hydrolyzed. All samples showed antioxidant properties through inhibition of free radicals, even at low concentrations hydrolyzate. The 50% inhibition (EC50) of the DPPH radical methodology occurred at concentrations below 3 mg / ml for all treatments, being the lowest concentration 1.36 mg / ml (lot 120 min) and the largest 2.70 mg / ml (Neutrase 30 min). In the ABTS method, higher concentrations were required for 50% inhibition of the radical, but still was less than 5%. The lowest concentration was 3.58 mg / mL (120 pepsin min) and the largest was 4.49 mg / mL (Neutrase 60 min). The size of the peptide chains to most treatments ranged from 1000 to 10000Da chains, whereas treatment with pepsin promoted percentage of peptides of higher molecular weight followed by Neutrase. The papain was the enzyme cleavage that generated more protein and peptides of smaller size, situated in the range from 100 to 1000 Da, which is related to the higher degree of hydrolysis. The properties observed in hydrolysates produced indicate that this is a potential food supplement because of its high protein value for food preservation additives, and applied in the pharmaceutical industry.
3

Reciclagem de resíduos do processamento de tilápia (Oreochromis niloticus) visando obter hidrolisado proteico como coproduto / Tilapia (Oreochromis niloticus) processing residues recycling to obtain protein hydrolysates as coproduct

Taciana Lunelli 08 October 2015 (has links)
O crescimento da produção e comercialização de pescado gera um aumento considerável na quantidade de resíduos. A escassez de reutilização e as formas incorretas de descarte tem sido preocupação constante das indústrias e dos pesquisadores, que buscam soluções para a melhor destinação dos mesmos. Buscando o conceito de empresa eco eficiente, são propostos tratamentos que levem à obtenção de coprodutos. A produção de \"farinha de peixe\" é a forma de aproveitamento do resíduo mais utilizada, porém apresenta baixo valor comercial. A elaboração de hidrolisados proteicos apresenta-se como uma alternativa de maior valor agregado. A clivagem proteica realizada por enzimas específicas pode gerar peptídeos biologicamente ativos, que apresentam propriedades funcionais e medicinais, bem como atividade antioxidante. O objetivo deste trabalho foi a elaboração e caracterização de hidrolisados proteicos de cabeças de tilápia (Oreochromis niloticus), a aferição da atividade antioxidante destes e sua relação com o tamanho de peptídeos, como forma de se obter e disponibilizar coprodutos, visando a sustentabilidade da cadeia produtiva desta espécie. O hidrolisado proteico de tilápia (HPT) foi obtido por hidrólise enzimática e empregando as enzimas Neutrase (Protemax NP-800), Papaína (Brauzyn-100) e Pepsina nos tempos 30, 60 e 120 minutos. O grau de hidrólise foi determinado através da metodologia com utilização do o-ftaldialdeído. A atividade antioxidante foi avaliada pelos ensaios do DPPH e ABTS+. O perfil de peptídeos foi avaliado através da separação por cromatografia em gel com coluna Superdex peptide. O grau de hidrólise para os tratamentos com a neutrase (30 min, 60 min, 120min) variou de 11,3% a 14,1%. No tratamento com a papaína (30 min, 60 min, 120 min) o grau de hidrólise foi superior ao observado com a enzima neutrase, apresentando variação de 21,14%a 25,28%. A variação para o tratamento com a pepsina (30 min, 60 min e 120 min) foi de 10,18% a 14,97% Todos os hidrolisados apresentaram propriedade antioxidante através da inibição de radicais livres, mesmo a concentrações baixas de hidrolisado. A inibição de 50% (EC50) dos radicais na metodologia de DPPH ocorreu com concentrações inferiores a 3mg/mL para todos os tratamentos, sendo a menor concentração 1,36 mg/mL (pepsina 120 min) e a maior 2,70 mg/mL (neutrase 30 min). Na metodologia de ABTS, concentrações superiores foram necessárias para a inibição de 50% dos radicais, porém ainda assim foram inferiores a 5%. A menor concentração foi 3,58 mg/mL (pepsina 120 min) e a maior foi de 4,49 mg/mL (neutrase 60 min). O tamanho das cadeias de peptídeos para a maioria dos tratamentos se situou entre cadeias de 1000 a 10000Da, sendo que o tratamento com pepsina promoveu porcentagem de peptídeos com maior peso molecular seguido pela neutrase. A papaína foi a enzima que promoveu maior clivagem de proteína e menores tamanhos de peptídeos, localizados na faixa de 100 a 1000 Da, valor relacionado ao seu maior grau de hidrólise. As propriedades observadas nos hidrolisados elaborados indicam que este pode ser um potencial suplemento alimentício devido ao seu elevado valor proteico, aditivos para conservação de alimentos e ainda aplicados na indústria farmacêutica. / The growth in production and marketing of fish generates a considerable increase in the amount of waste. The scarcity of re-used products and incorrect disposal forms has been a constant concern of industries and researchers who seek solutions for better allocation thereof. Seeking an efficient eco company concept, proposed treatments are leading to obtaining co-products. The production of \"fish meal\" with the residues is the most common use for the waste, but has a low commercial value. The preparation of protein hydrolysates is presented as an alternative with higher added value. The protein cleavage performed by specific enzymes can generate biologically active peptides which exhibit functional and medicinal properties as well as antioxidant activity. The objective of this work was the preparation and characterization of protein hydrolysates of tilapia (Oreochromis niloticus) , the measurement of antioxidant activity of these and its relation to the size of peptides as a way to obtain and provide co-products , aimed at the sustainability of the chain production of this species. The protein hydrolyzate of tilapia (HPT) was obtained by enzymatic hydrolysis and employing the enzyme Neutrase (Protemax NP- 800), Papain (Brauzyn - 100) and Pepsin at 30, 60 and 120 minutes. The degree of hydrolysis was determined using o- phthaldialdehyde . In the treatment with papain (30 min, 60 min, 120 min) the degree of hydrolysis was higher than that observed with Neutrase enzyme, showing variation of 21.14% to 25.28%. The variation for treatment with pepsin (30 min, 60 min and 120 min) was 10.18% and 14.97% hydrolyzed. All samples showed antioxidant properties through inhibition of free radicals, even at low concentrations hydrolyzate. The 50% inhibition (EC50) of the DPPH radical methodology occurred at concentrations below 3 mg / ml for all treatments, being the lowest concentration 1.36 mg / ml (lot 120 min) and the largest 2.70 mg / ml (Neutrase 30 min). In the ABTS method, higher concentrations were required for 50% inhibition of the radical, but still was less than 5%. The lowest concentration was 3.58 mg / mL (120 pepsin min) and the largest was 4.49 mg / mL (Neutrase 60 min). The size of the peptide chains to most treatments ranged from 1000 to 10000Da chains, whereas treatment with pepsin promoted percentage of peptides of higher molecular weight followed by Neutrase. The papain was the enzyme cleavage that generated more protein and peptides of smaller size, situated in the range from 100 to 1000 Da, which is related to the higher degree of hydrolysis. The properties observed in hydrolysates produced indicate that this is a potential food supplement because of its high protein value for food preservation additives, and applied in the pharmaceutical industry.
4

Developing Serum-Free Media Via Bioprocessing For Cultivated Seafood Products

Batish, Inayat 08 September 2022 (has links)
Global food production management has become a challenge with an anticipated population of 10 billion people by 2050 and the ongoing COVID-19 epidemic. Seafood is a vital food source due to its widespread consumption, excellent nutrient profile, and low feed conversion ratio, rendering its sustainable production quintessential. Cellular agriculture or cultured meat can increase seafood production; however, the conventional use of Fetal Bovine Serum (FBS) in culture media restricts its utilization at an industrial level. FBS is effective but has many limitations: unethical animal extraction, high demand and low supply, poorly defined ingredients, variable performance, and high cost that impedes the feasibility and commercial viability of cellular agriculture. Thus, employing serum-free media becomes a quintessential need for cellular agriculture. This project aims to replace or reduce the typical 10% serum usage in Zebrafish embryonic stem cell (ESC) production media with protein hydrolysates derived from low-cost natural sources with high protein content. Enzymatic hydrolysis was performed on nine sources: insects (black army fly and cricket), plants (pea), fungi (mushroom and yeast), algae, and marine invertebrates (oyster, mussel, and lugworm). The resulting hydrolysates were evaluated for serum replacement in zebrafish ESCs. All hydrolysates were used at five different concentrations (10, 1 0.1, 0.01 and 0.001 mg/mL) in serum concentrations of 10%, 5%, and 0% with four biological replicates. The best hydrolysate sources and concentrations were selected for further testing at 2.5% and 1% serum concentrations. All hydrolysates, except for cricket, could restore or significantly increase cell growth with 50% less serum at a concentration of 0.1-0.001mg/mL. Protein hydrolysate concentration of 10 and 1mg/mL was toxic for cells. Additionally, the eight hydrolysates could reduce serum concentrations up to 75–90%. However, no protein hydrolysate could completely replace serum, as cells using only protein hydrolysates exhibited morphological aberrations and decreased growth. Replacing serum with protein hydrolysates lowers cellular agriculture's overall cost, thus enabling the commercialization of cultured meat and the development of a sustainable food system. In the future, blending various protein hydrolysate sources with or without the addition of conventional growth factors could be done to create the ideal serum-free media. / Doctor of Philosophy / With a predicted population of 10 billion by 2050 and the ongoing COVID-19 outbreak, the management of global food production has become a dilemma. However, due to its widespread consumption and good nutrient profile, seafood is an essential food supply, making its sustainable production indispensable. Both capture fisheries and aquaculture are conventional ways to produce seafood. However, they are under tremendous pressure and require alternatives that can alleviate this demand and contribute to the sustainable growth of seafood. In-vitro cultured meat, also known as lab-grown meat, is a novel technique with the potential to supplement the traditional fish sector. It appears a great option, as it completely imitates meat and offers numerous environmental, financial, and health advantages. A culture medium supports the existence, survival, growth, and multiplication of meat-producing cells and tissues in cell-based meat. However, the culture medium uses a Fetal Bovine Serum (FBS) supplement, which dramatically increases the cost and raises many ethical concerns as it is derived from a cow's fetus. In this thesis, we substitute FBS with protein hydrolysates derived from nine distinct sources. Hydrolysing proteins with enzymes produce protein hydrolysates, rich in nutrients and peptides that promote cell development. Enzymes were used to hydrolyse nine unique and protein-rich sources, including insects (black army fly and cricket), plants (pea), fungi (mushroom and yeast), algae, and marine creatures (oyster, mussel, and lugworm). The resultant hydrolysates were investigated for replacement of serum in cell culture. Eight protein hydrolysates successfully replaced 90% of serum without impairing cell growth and structure but could not replace serum entirely. In the future, serum-free media could be created by combining these various protein hydrolysates with or without adding other growth-promoting components.
5

Production and fractionation of antioxidant peptides from soy protein isolate using sequential membrane ultrafiltration and nanofiltration

Ranamukhaarachchi, Sahan January 2012 (has links)
Antioxidants are molecules capable of stabilizing and preventing oxidation. Certain peptides, protein hydrolysates, have shown antioxidant capacities, which are obtained once liberated from the native protein structure. Soy protein isolates (SPI) were enzymatically hydrolyzed by pepsin and pancreatin mixtures. The soy protein hydrolysates (SPH) were fractionated with sequential ultrafiltration (UF) and nanofiltration (NF) membrane steps. Heat pre-treatment of SPI at 95 degrees celsius (C) for 5 min prior to enzymatic hydrolysis was investigated for its effect on peptide distribution and antioxidant capacity. SPH were subjected to UF with a 10 kDa molecular weight cut off (MWCO) polysulfone membrane. UF permeate fractions (lower molecular weight than 10 kDa) were fractionated by NF with a thin film composite membrane (2.5 kDa MWCO) at pH 4 and 8. Similar peptide content and antioxidant capacity (α=0.05) were obtained in control and pre-heated SPH when comparing the respective UF and NF permeate and retentate fractions produced. FCR antioxidant capacities of the SPH fractions were significantly lower than their ORAC antioxidant capacities, and the distribution among the UF and NF fractions was generally different. Most UF and NF fractions displayed higher antioxidant capacities when compared to the crude SPI hydrolysates, showing the importance of molecular weight on antioxidant capacity of peptides. The permeate fractions produced by NF at pH 8 displayed the highest antioxidant capacity, expressed in terms of Trolox equivalents (TE) per total solids (TS): 5562 μmol TE/g TS for control SPH, and 5187 μmol TE/g TS for pre-heated SPH. Due to the improvement in antioxidant capacity of peptides by NF at pH 8, the potential for NF as a viable industrial fractionation process was demonstrated. Principal component analysis (PCA) of fluorescence excitation-emission matrix (EEM) data for UF and NF peptide fractions, followed by multi-linear regression analysis, was assessed for its potential to monitor and identify the contributions to ORAC and FCR, two in vitro antioxidant capacity assays, of SPH during membrane fractionation. Two statistically significant principal components (PCs) were obtained for UF and NF peptide fractions. Multi-linear regression models (MLRM) were developed to estimate their fluorescence and PCA-captured ORAC (ORAC-FPCA) and FCR (FCR-FPCA) antioxidant capacities. The ORAC-FPCA and FCR-FPCA antioxidant capacities for NF samples displayed strong, linear relationships at different pH conditions (R-squared>0.99). Such relationships are believed to reflect the individual and relative combined contributions of tryptophan and tyrosine residues present in the SPH fractions to ORAC and FCR antioxidant capacities. Therefore, the proposed method provides a tool for the assessment of fundamental parameters of antioxidant capacities captured by ORAC and FCR assays.
6

The cardio-renal effect of pea protein hydrolysate in a chronic kidney disease rat model

Prairie, Natalie Paula 03 January 2012 (has links)
Pea protein hydrolysate (PPH) has antihypertensive effects and prostanoids have been implicated in renal diseases. To investigate the role of PPH and prostanoids on renal and cardiovascular effects in cardio-renal disease, normal and diseased Han:SPRD-cy rats were given diets containing either 0, 0.5% or 1% PPH for 8 weeks. At termination, diseased rat kidneys displayed increased renal cyst growth, fibrosis, plasma creatinine and lower monocyte chemoattractant protein-1. Diseased rats also exhibited left ventricular (LV) hypertrophy, elevated systolic and diastolic blood pressures and LV end diastolic and systolic pressures. Four of five prostanoids were elevated in diseased rat kidneys. PPH attenuated systolic blood pressure, but not other components of the cardio-renal syndrome. PPH also increased select prostanoids in normal and diseased rats. Thus, dietary PPH attenuates hypertension in the Han:SPRD-cy rat, but does not ameliorate other components of disease, possibly due to increased prostanoid effects or an insufficient treatment length.
7

The cardio-renal effect of pea protein hydrolysate in a chronic kidney disease rat model

Prairie, Natalie Paula 03 January 2012 (has links)
Pea protein hydrolysate (PPH) has antihypertensive effects and prostanoids have been implicated in renal diseases. To investigate the role of PPH and prostanoids on renal and cardiovascular effects in cardio-renal disease, normal and diseased Han:SPRD-cy rats were given diets containing either 0, 0.5% or 1% PPH for 8 weeks. At termination, diseased rat kidneys displayed increased renal cyst growth, fibrosis, plasma creatinine and lower monocyte chemoattractant protein-1. Diseased rats also exhibited left ventricular (LV) hypertrophy, elevated systolic and diastolic blood pressures and LV end diastolic and systolic pressures. Four of five prostanoids were elevated in diseased rat kidneys. PPH attenuated systolic blood pressure, but not other components of the cardio-renal syndrome. PPH also increased select prostanoids in normal and diseased rats. Thus, dietary PPH attenuates hypertension in the Han:SPRD-cy rat, but does not ameliorate other components of disease, possibly due to increased prostanoid effects or an insufficient treatment length.
8

Production and fractionation of antioxidant peptides from soy protein isolate using sequential membrane ultrafiltration and nanofiltration

Ranamukhaarachchi, Sahan January 2012 (has links)
Antioxidants are molecules capable of stabilizing and preventing oxidation. Certain peptides, protein hydrolysates, have shown antioxidant capacities, which are obtained once liberated from the native protein structure. Soy protein isolates (SPI) were enzymatically hydrolyzed by pepsin and pancreatin mixtures. The soy protein hydrolysates (SPH) were fractionated with sequential ultrafiltration (UF) and nanofiltration (NF) membrane steps. Heat pre-treatment of SPI at 95 degrees celsius (C) for 5 min prior to enzymatic hydrolysis was investigated for its effect on peptide distribution and antioxidant capacity. SPH were subjected to UF with a 10 kDa molecular weight cut off (MWCO) polysulfone membrane. UF permeate fractions (lower molecular weight than 10 kDa) were fractionated by NF with a thin film composite membrane (2.5 kDa MWCO) at pH 4 and 8. Similar peptide content and antioxidant capacity (α=0.05) were obtained in control and pre-heated SPH when comparing the respective UF and NF permeate and retentate fractions produced. FCR antioxidant capacities of the SPH fractions were significantly lower than their ORAC antioxidant capacities, and the distribution among the UF and NF fractions was generally different. Most UF and NF fractions displayed higher antioxidant capacities when compared to the crude SPI hydrolysates, showing the importance of molecular weight on antioxidant capacity of peptides. The permeate fractions produced by NF at pH 8 displayed the highest antioxidant capacity, expressed in terms of Trolox equivalents (TE) per total solids (TS): 5562 μmol TE/g TS for control SPH, and 5187 μmol TE/g TS for pre-heated SPH. Due to the improvement in antioxidant capacity of peptides by NF at pH 8, the potential for NF as a viable industrial fractionation process was demonstrated. Principal component analysis (PCA) of fluorescence excitation-emission matrix (EEM) data for UF and NF peptide fractions, followed by multi-linear regression analysis, was assessed for its potential to monitor and identify the contributions to ORAC and FCR, two in vitro antioxidant capacity assays, of SPH during membrane fractionation. Two statistically significant principal components (PCs) were obtained for UF and NF peptide fractions. Multi-linear regression models (MLRM) were developed to estimate their fluorescence and PCA-captured ORAC (ORAC-FPCA) and FCR (FCR-FPCA) antioxidant capacities. The ORAC-FPCA and FCR-FPCA antioxidant capacities for NF samples displayed strong, linear relationships at different pH conditions (R-squared>0.99). Such relationships are believed to reflect the individual and relative combined contributions of tryptophan and tyrosine residues present in the SPH fractions to ORAC and FCR antioxidant capacities. Therefore, the proposed method provides a tool for the assessment of fundamental parameters of antioxidant capacities captured by ORAC and FCR assays.
9

O efeito da suplementação de soro de leite sobre os linfocitos de ratos Wistar / Supplementation effects of whey proteins in lymphocytes of Wistar rats

Cavalheiro, Laura Andrade 22 February 2007 (has links)
Orientador: Celio Kenji Miyasaka / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-08T03:26:53Z (GMT). No. of bitstreams: 1 Cavalheiro_LauraAndrade_M.pdf: 809451 bytes, checksum: 708c6f3b4585edd72f8cc635a5c73faf (MD5) Previous issue date: 2007 / Resumo: As proteínas presentes no soro de leite têm demonstrado um grande número de efeitos benéficos, como atividade anticarcinogênicas, efeito antiulcerogênica e função imunoestimulatória. Esta propriedade imunoestimulatória está sendo relacionada à possível manipulação da glutationa intracelular. Os linfócitos são importantes células do sistema de defesa celular e humoral. Este trabalho teve como objetivo estudar os efeitos da suplementação com soro de leite sobre os linfócitos de ratos Wistar. Cento e vinte animais foram divididos em 4 grupos (n = 30), sendo um grupo controle (C) e os demais suplementados com caseinato de cálcio (K), isolado protéico de soro de leite (I) e hidrolisado protéico de soro de leite (H). Os ratos foram mantidos em gaiolas individuais com água e ração à vontade. Aos 18 dias de suplementação amostras de sangue foram recolhidas para realização de hemograma. Dez dias depois, os animais foram sacrificados e os linfócitos mesentéricos retirados, contados em câmara de Neubauer e incubados (5x107células/ml) em presença de peróxido de hidrogênio. A viabilidade celular foi avaliada antes e depois da incubação. Também foram avaliadas as atividades enzimáticas da glutationa redutase (GSH-Red) e da glutationa peroxidase (GSH-Px). Apesar de um maior consumo de ração, os animais do grupo C não foram os que apresentaram maior ganho de peso. Estatisticamente, seu ganho de peso foi maior que o do grupo K, menor que do grupo I e não diferiu significantemente do grupo H. Os animais do grupo H apresentaram número de linfócitos 134% maior quando comparado aos grupos I e K e 158% mais elevado em relação ao grupo C. Na análise de sangue o número de linfócitos (x10³ celulas/mL) dos animais dos grupos H e I foram estatisticamente maiores que os demais grupos. Os linfócitos dos animais do grupo H tiveram a sua viabilidade diminuída apenas 4,08% após incubação com peróxido de hidrogênio enquanto que no grupo C a diminuição de viabilidade foi de 28,9%. A enzima GSH-Red dos animais do grupo H (38,22 pmols . min-1. mg proteina-1) se mostrou maior que dos animais do grupo C (17,64 pmols . min-1. mg proteina-1). Não houve diferenças entre os grupos na determinação de GSH-Px. Assim, verificou-se a qualidade nutricional atribuída ao soro de leite e que este pode interferir no metabolismo de linfócitos / Abstract: The whey proteins have demonstrated some beneficial effects, as anticarcinogenic activity, antiulcerogenic effect and immunostimulanting function. These immunostimulanting properties have being related to the possible manipulation of intracellular glutathione. The lymphocytes are important cells of the cellular and humoral defense system. The aim of this work was to study the effect of the whey proteins supplementation on lymphocytes of Wistar rats. One hundred and twenty animals were randomly distributed in 4 groups (n = 30): one control group (C) while the others were supplemented with calcium caseinate (K), whey protein isolated (I) and whey protein hydrolysate (H). The rats were maintained in individual cages with water and ration ad libitum. After 18 days of supplementation, blood samples were collected for hemogram accomplishment. Ten days later, the animals were killed and the mesenteric lymphocytes were counted in Neubauer¿s camara and incubated (5x107células/ml) in the presence of hydrogen peroxide. The cellular viability was evaluated before and after the incubation. The enzymatic activities of glutathione reductase (GSH-Red) and of glutathione peroxidase (GSH-Px) were also evaluated. Animals of group C had the highest feed consumption, although its body weight gain was the same as group H, greater than group K and lesser than group I. The group H animals have presented number of lymphocytes 134% greater when compared with groups I and K and 158% more than group C animals. The blood analysis have shown that the number of lymphocytes (x103 cells/mL) of group H animals were bigger than the others groups / Mestrado / Nutrição Experimental e Aplicada à Tecnologia de Alimentos / Mestre em Alimentos e Nutrição
10

Serum-free media development using black soldier fly protein isolate and hydrolysate for cultivated meat

Garg, Palak 03 January 2024 (has links)
The global demand for animal proteins is projected to rise by 14% by 2030, amplifying the environmental toll of conventional animal-based protein production. Cultivated meat technology can alleviate the growing demand for protein and address the environmental and ethical concerns associated with conventional livestock farming. However, it faces a critical challenge: the high cost of cell culture media, primarily due to the use of Fetal Bovine Serum (FBS). Substituting serum with protein hydrolysates reduces the production expense of cultivated meat products and promotes establishing a sustainable food system. This study explores black soldier fly larvae (Hermetia illucens) as an emerging ethical and cost-effective alternative protein source to replace serum in media, particularly for cultivated meat production. The development of BSFL protein isolate involved defatting the larva, followed by protein extraction. The protein isolate was then hydrolyzed using an enzyme to produce BSFL hydrolysates. The goal was to supplement the protein isolate and hydrolysates with a serum-free media (B8) and determine their efficacy in replacing the 20% serum requirement for the cell culture of Bovine Satellite Cells. The BSFL protein isolate developed had a crude protein content of 80.42% and an amino acid composition conducive to cell proliferation. Experimental concentrations, ranging from 0.006 mg/ml for hydrolysate to 0.06 mg/ml for protein isolate, exhibited enhanced cell growth. Data from dsDNA quantification revealed no significant difference in growth between cells fed serum-containing growth media (BSC-GM) and BSFL protein hydrolysate (BSFLH_1h) over a short-term study. Results from the multi-passage growth study revealed that BSFLH_1h significantly improved cell growth compared to B8 over 4 passages. However, its doubling time was slower than BSC-GM. Additionally, it was observed that the protein isolate and hydrolysate were cytotoxic at higher concentrations. In the future, identifying and removing the cytotoxic compounds can further optimize the media composition. Immunostaining using Pax7 and DAPI identified supplemented media-maintained satellite cell identity of Bovine satellite cells, offering crucial insights into cellular proliferation. Furthermore, since each cell type requires varying serum and nutrients, testing these isolates and hydrolysates on different cell lines can provide better insight into creating a universal serum-free media. / Master of Science in Life Sciences / The global demand for animal proteins is projected to rise by 14% by 2030, amplifying the environmental toll of conventional animal-based protein production. Meat, dairy, aquaculture, and eggs significantly contribute to food-related emissions and occupy a vast portion of global farmland. Cultivated meat production can alleviate the growing demand for protein and address the environmental and ethical concerns associated with conventional livestock farming. Currently, the production of cultivated meat faces a significant hurdle: the high cost of culture media, primarily attributed to the use of Fetal Bovine Serum (FBS). Substituting serum with protein isolates or hydrolysates reduce the production expense of cultivated meat products and promotes a sustainable food system. Protein isolate and hydrolysates derived from black soldier fly larvae (Hermetia illucens) are rich in protein and essential amino acids and can be used as a cost-effective alternative to serum in cell culture media. The protein isolate and hydrolysates derived from BSFL were tested as supplements to a serum-free media (B8) to evaluate their effectiveness in supporting the growth of Bovine Satellite Cells. The protein hydrolysate demonstrated enhanced cell growth at experimental concentrations. However, it could not completely replace serum requirements without slowing cell growth. Despite challenges such as cytotoxicity at higher concentrations, our study suggests that further refinements and application on various cell types can assist in creating a sustainable and affordable serum-free media for cultivated meat production.

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