Rhizomania, caused by beet necrotic yellow vein virus (BNYVV), has been considered as an economically important disease around the world because of the extreme reduction in sugar beet yield and sugar content in affected plants. The spread of rhizomania all over the world, including the emergence of resistance- breaking virus isolates, have been become a major concern for the plant pathologists and plant breeders aiming at improving sugar beet resistance to   BNYVV as well as better understanding sugar beet-virus interactions during disease development. The main focus of this project is to elucidate the role of P25-interacting partner, the VIP1 transcription factor, in activation of transcription.  The isolation of the gene-of-interest (VIP1) was performed by RT-PCR on total RNA preparations extracted from root tissue of sugar beet (Beta vulgaris ssp. vulgaris).  The isolated gene of interest was cloned using gateway system into a binary expression vector and the obtained construct was then transformed into Agrobacterium tumefaciens for analysing transient expression in the experimental host (Nicotinana benthamiana).  Dual-luciferase promoter activity assay was performed on isolated leaf discs co-expressing P25 and VIP1 and compared to appropriate controls.  Six promoter constructs were tested. However, we observed an increase in luciferase activity (1.8-4.2-fold) upon co-expression of P25 and VIP1 only for two constructs tested, although the increase was not supported by Student’s t-test at 0.05 significance level. Nevertheless, the luciferase activity assay data for these two constructs were consistent with RNA-seq and RT-qPCR data obtained previously showing upregulation of the expression of these two specific sugar beet genes during BNYVV infection in sugar beets.     Thus, the results support our hypothesis that the interaction of the virus virulence factor P25 with VIP1 transcription factor is needed to activate transcription of certain genes in the nucleus for the virus benefit.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Ingredientes de origem vegetal sÃo cada vez mais procurados para compor as raÃÃes destinadas à carcinicultura. A busca por tais matÃrias primas gera uma grande demanda do mercado por ingredientes tradicionais que sÃo produzidos na sua maioria em outras regiÃes, elevando o custo das formulas. A utilizaÃÃo de ingredientes regionais pode proporcionar um melhor retorno aos carcinicultores do Nordeste, principal produtor nacional de camarÃes marinhos. O presente trabalho avaliou o desempenho zootÃcnico de juvenis de Litopenaeus vannamei quando alimentados com dietas contendo farelo de algodÃo como substituto parcial do farelo de soja e farinha de trigo. Juvenis de L. vannamei de 1,51  0,05g foram estocados em tanques de 500 L na densidade de 70 camarÃes/m2 durante 72 dias em um sistema com recirculaÃÃo e filtragem continua. Foi utilizada uma dieta controle (FA0), contendo 0% de inclusÃo de farelo de algodÃo, sendo as demais dietas acrescidas de farelo de algodÃo em nÃveis de 3%, 6%, 9% e 12%. Ao final do estudo foram avaliadas as mÃdias para sobrevivÃncia (%), peso corporal final (g), ganho em peso semanal (g), produtividade (g m-2), consumo aparente de raÃÃo (g camarÃo-1) e fator de conversÃo alimentar. Os resultados mostraram que nÃo houve diferenÃa estatisticamente significativa entre os tratamentos para todos os parÃmetros avaliados. Tais resultados nos permitem concluir que à possÃvel reduzir os nÃveis de inclusÃo de farinha de trigo em 17% e farelo de soja em 11%, substituindo por um ingrediente regional (farelo de algodÃo), reduzindo os custos na formulaÃÃo de raÃÃes para o L. vannamei. / Ingredients of vegetable origin are increasingly sought to compose the feeds for farm-reared shrimp. The search for such raw materials generates a large market demand for traditional ingredients that are produced mostly in other regions, raising formula cost. The use of regionally-available ingredients can provide a better return to shrimp farmers in the Northeastern Brazil, the main national producer of farmed shrimp. This study evaluated the growth performance of juvenile Litopenaeus vannamei when fed diets containing cottonseed meal as a partial substitute for soybean meal and wheat flour. L. vannamei juveniles of 1.51  0.05 g were stocked in 500 L tanks at a density of 70 shrimp m-2 for 72 days in a continuous water recirculation and filtering system. A control diet (FA0) was used, containing no inclusion of cottonseed meal. The other diets were prepared to contain cottonseed meal at 3%, 6%, 9% and 12% of the diet. At the end of the study, mean values were evaluated for shrimp survival (%), shrimp final body weight (g), shrimp weekly weight gain (g), shrimp yield (g m-2), apparent shrimp feed intake (g shrimp-1) and feed conversion ratio. Results showed no statistically significant difference between dietary treatments for all parameters evaluated. These results allow us to conclude that it is possible to reduce the inclusion levels of wheat flour and soybean meal at 17% and 11%, respectively, substituting for a regionally-available ingredient (cottonseed meal), reducing formula costs for feeds of L. vannamei.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / A produÃÃo mundial de farinha de peixe e derivados estagnou ao longo dos Ãltimos anos. Em contrapartida, a aquicultura à o setor de produÃÃo de alimento que mais cresce anualmente. Atualmente o cultivo de organismos aquÃticos marinho depende da farinha de peixe e seus derivados. Ingredientes vegetais tÃm sido testados como fontes alternativas e viÃveis de proteÃna para alimentaÃÃo destes organismos. O glÃten de milho surge como um ingrediente promissor, apresentando 60% de proteÃna bruta (PB). Este trabalho avaliou a substituiÃÃo da proteÃna da farinha de peixe pela proteÃna do glÃten de milho em dietas prÃticas para camarÃes marinhos cultivados em tanques experimentais. Juvenis do camarÃo branco, Litopenaeus vannamei, foram estocados em tanques em sistema de recirculaÃÃo de Ãgua (RAS) na densidade de 70 camarÃes m-2 durante um perÃodo de 72 dias. Cinco dietas foram formuladas, quatro experimentais e uma controle, com 37,5-38,3% PB e 17,5-18,0% EB (energia bruta). As dietas experimentais foram formuladas a partir de uma dieta basal (12% farinha de peixe salmÃo (importada) + 2,4% farinha de resÃduo de peixes marinhos (nacional), pela substituiÃÃo (15, 30, 45 e 60%) da proteÃna da farinha de peixe pela proteÃna do glÃten de milho, com suplementaÃÃo de aminoÃcidos essenciais: lisina, metionina e triptofano (dieta basal: 2,75% lisina, 1,09% metionina e 0,75% triptofano). Ao final do experimento observou-se que houve diferenÃa significativa (P<0,05) para variÃveis de desempenho zootÃcnico, peso corporal final (g) e ganho em peso semanal (g), entre a dieta controle GM0 (17,50  1,15 g e 1,70  0,11 g, respectivamente) e a dieta com 60% de substituiÃÃo GM60 (15,65  1,01 g e 1,52  0,10 g, respectivamente). As demais variÃveis de desempenho zootÃcnico: sobrevivÃncia (94,4  1,88 %), produtividade (956,08  28,11 g m-2), consumo alimentar aparente (34,8  0,58 g camarÃo-1) e FCA (2,3  0,04) nÃo apresentaram diferenÃa estatisticamente significativa (P&#8805;0,05) entre as dietas. O glÃten de milho pode substituir a farinha de peixe em atà 50 g kg-1 nas dietas, sem prejuÃzo zootÃcnico aos camarÃes, reduzindo a participaÃÃo em 30% do ingrediente animal como fonte proteica na raÃÃo. Uma substituiÃÃo mais drÃstica com inclusÃo de 78 g kg-1 de glÃten de milho pode causar uma queda moderada no desempenho zootÃcnico dos camarÃes. Entretanto, a reduÃÃo de 45% na participaÃÃo da farinha de peixe serà provavelmente vantajosa do ponto de vista econÃmico (melhor relaÃÃo custo: benefÃcio). / Global production of fish meal and derivatives has stalled in the last few years. On the other hand, aquaculture has grown rapidly representing today the fastest food production sector. However, farm-reared fish and shellfish still relies heavily on fish meal and derivates as a dietary protein source. Plant ingredients have been tested as alternative and viable sources of protein.Corn gluten is a promising ingredient, as it contains 60% crude protein (CP). This study has evaluated the replacement of fish meal protein by protein from corn gluten meal in practical diets for marine shrimp farmed in experimental tanks. Juvenile white shrimp, Litopenaeus vannamei, were stocked in tanks under a recirculating water system (RAS) at a density of 70 shrimp m-2 for a period of 72 days. Five diets were formulated, four experimental and one control, with 37.5 to 38.3% CP and 17.5 to 18.0% GE (gross energy). Experimental diets were formulated based on a basal diet by replacing 5, 30, 45 and 60% of the fish meal CP by corn gluten protein and supplementing them with the essential amino acids lysine, methionine and tryptophan. At the end of the experimental period, it was observed that there was significant difference (P<0.05) in the growth performance variables, final body weight (g) and weekly weight gain (g) between the control diet GM0 (17.50  1 15 g and 1.70  0.11 g, respectively) and the diet with 60% replacement GM60 (15.65  1.01 and 1.52  0.10 g, respectively). The other production performance variables, i.e., survival (94.4  1.88%), productivity (956.08  28.11 g m-2), feed consumption (34.8  0.58 g shrimp-1) and FCR (2.3  0.04), showed no statistically significant difference (P &#8805; 0.05) among dietary treatments. Gluten meal could replace fish meal up to 50 g kg-1 in diets without losses to shrimp performance, reducing 30% in the inclusion of animal ingredients as protein sources in the diet. A more drastic replacement of fish meal with an inclusion of 78 g kg-1 of corn gluten caused a moderate decrease in shrimp growth performance. However a 45%-reduction in the use of fish meal is likely to be advantageous from an economic standpoint (cost: benefit ratio).

Protein phosphorylation is an important post-translational modification of proteins, which can either activate or inhibit the function of a given protein. The enzymes, protein kinases and protein phosphatases catalyze the phosphorylation and dephosphorylation of target proteins, respectively. Protein kinases catalyze the transfer of γ-phosphate from ATP to serine, threonine or tyrosine residues in target proteins. They are traditionally classified as protein serine/threonine kinases and protein tyrosine kinases based on the amino acid to which they transfer the phosphate group. Protein tyrosine kinases play vital roles in numerous pathways that regulate growth, development and oncogenesis in animals. However, no protein tyrosine kinase has been cloned so far from plants. The sequence motif, CW(X)6RPXF of sub-domain XI is well conserved among biochemically characterized protein tyrosine kinases from human, rat, mice, worm, fruitfly and Dictyostelium. To seek plant genes encoding tyrosine kinase, we have performed extensive genome-wide analysis of Arabidopsis thaliana using the delineated tyrosine kinase from animal systems. Repetitive database mining with CW(X)6RPXF sequence motif revealed the presence of 57 different protein kinases that have tyrosine kinase motifs. Myosin light chain protein kinase was identified as false positive with this motif. Multiple sequence alignment of all the 57 kinases indicated the presence of twelve conserved sub-domains in their kinase catalytic domain. Out of the 12 sub-domains present in protein kinases, sub-domain VIb confers serine/threonine kinase Specificity and sub-domains VIII and XI confer tyrosine kinase specificity. All the 57 kinases were Verified to contain CW(X) 6RPXF in sub-domain XI. However, the catalytic domain of all the catalogued kinases contain KXXN motif in sub-domain VIb, which is indicative of serine/threonine Kinase specificity. None of the kinases had the tyrosine kinase consensus motif RAA or ARR in sub-domain VIb. Thus, the catalytic domains of all the identified Arabidopsis protein kinases have motifs for serine/threonine specificity in sub-domain VIb and tyrosine kinase motif in sub-domain XI. These results indicate that perhaps all the kinases belong to the dual-specificity kinase family. Hence, we have tentatively named these protein sequences as STY (serine/threonine/tyrosine) protein kinases. To examine the relationships of Arabidopsis STY protein kinases, a topographic cladogram was constructed. Casein kinase 1 was used as an outgroup to perceive the true class of STY protein kinase family. Neighbor joining tree was constructed with the full-length protein sequences following the alignments. Dendrogram of STY protein kinases suggested that the kinases are mainly clustered into four groups. Group I includes kinases related to ATN1-like kinases, peanut STY related kinases, soybean GmPK6-like kinases and ATMRK1-like kinases. Group II consists of MAP3K-like kinases, CTR1 and EDR1 related kinases. Group III includes protein kinases that harbor ankyrin domain repeat motifs. These kinases are related to Medicago sativa ankyrin kinase, MsAPK1. Group IV consists of light sensory kinases that are related to Ceratodon purpureus phytochrome kinase. C. purpureus light sensory kinase has both phytochrome and protein kinase domains. However, the protein kinases of group IV do not have a phytochrome domain. BLAST analysis was performed using CW(X)6RPXF motif against all the available plant sequences in the database. We retrieved 11 rice protein kinases and 14 Dictyostelium kinases. In addition, we obtained STY protein kinases from wheat, barley, soybean, tomato, beech and alfalfa. Dendrogram analysis indicated that the plant STY protein kinases are clustered in similar manner as observed for Arabidopsis. Large number of sequences were retrieved when the tyrosine kinase motif CW(X)6RPXF was used to perform BLAST analysis against all the known sequences from animals. As large numbers of protein tyrosine kinases are available in animals, we have used representative kinases of each family towards the construction of phylogenetic tree. The main difference between the animal and plant tyrosine kinases is in the consensus motif conferring the tyrosine and serine/threonine specificity in the sub-domain VIb. Animal tyrosine kinases have consensus ARR/RAA in sub-domain VIb and plant kinases have KXXN which is indicative of serine/threonine specificity. Expression analysis of Arabidopsis STY protein kinases was performed using Genevestigator online search tool Meta-Analyzer. Genes were grouped based on their relative expression levels during a specific growth stage, in a particular organ or following different environmental stresses. Various kinases are highly expressed in stamens and seeds while some kinases are expressed ubiquitously. A number of biotic and abiotic factors upregulated plant STY protein kinases. Gene expression data suggests the importance of STY protein kinases in plant growth and development. Genome-wide analysis is supported by phosphoproteomics in Arabidopsis seedlings. Evidence for tyrosine phosphorylated proteins is provided by alkaline hydrolysis, phosphoamino acid analysis and peptide mass fingerprinting. Alkaline treatment detected two proteins corresponding to 46 and 37.5 kD. Phosphoamino acids analysis confirmed their dual-specificity nature. MALDI mass spectrometry and peptide mass fingerprinting analysis identified these two proteins as ATN1 and peanut serine/threonine/tyrosine protein kinase like protein from Arabidopsis. To further support the in silico approach, we have overexpressed one of the identified Arabidopsis thaliana serine/threonine/tyrosine protein kinases (AtSTYPK) in E. coli. The recombinant kinase was induced with IPTG and purified by using nickel-nitrilotriacetic acid affinity chromatography. AtSTYPK exhibited a strong preference for manganese over magnesium for kinase activity. The autophosphorylation activity of AtSTYPK was inhibited by the addition of calcium to reaction buffer containing manganese. The rate of autophosphorylation reaction was linear with increasing time and protein concentration. The AtSTYPK phosphorylated histone H1 (type III-S), and myelin basic protein (MBP) in substrate phosphorylation reaction and it did not phosphorylate casein or enolase. To see whether calcium or magnesium inhibits phosphorylation of MBP, we have performed the reaction in the presence of combination of different metal ions. The MBP phosphorylation reaction is more efficient in the presence of Mg2++ Mn2+ than Ca2++ Mn2+ under the same conditions. The recombinant kinase autophosphorylated on serine, threonine and tyrosine residues and phosphorylated myelin basic protein on threonine and tyrosine residues. The AtSTYPK harbors a manganese-dependent serine/threonine kinase domain, COG3642. H248 and S265 on COG3642 are conserved in AtSTYPK and the site-directed mutation of H248 to alanine resulted in loss of serine/threonine kinase activity, but the mutation of S265 to alanine showed a slight increase in its kinase activity. The protein kinase activity is regulated by various mechanisms that include autophosphorylation, protein phosphorylation by other kinases and by the action of regulatory domains or subunits. The role of tyrosine residues in the regulation of peanut dual-specificity kinase activity is well documented, but the importance of serine and threonine residues in the regulation of dual-specificity protein kinase is not studied so far. The kinase activity is generally regulated by phosphorylation of one or more residues within the kinase activation loop. The role of threonine residues in the kinase activation loop and the TEY motif of AtSTYPK were investigated in the present study. Four threonine residues in the activation loop and a T208 in the TEY sequence motif were converted to alanine to study their role in the regulation of kinase activity. The protein kinase activity was abolished when T208 and T293 of the activation loop were converted to alanine. Interestingly, the conversion of T284 in the activation loop to alanine resulted in an increase in both auto- and substrate phosphorylations. The mutation of T288 and T291 to alanine had no effect on kinase activity. There are eight serine residues in the kinase catalytic domain of AtSTYPK and surprisingly there is no serine residue in the kinase activation loop. So it is worthwhile to see how phosphorylation of serine residues regulates the dual-specificity protein kinase activity. The role of each serine residue was studied individually by substituting them with alanine. Serines at positions 215, 259, 269 and 315 regulate the kinase activity both in terms of autophosphorylation and substrate phosphorylation of myelin basic protein. The mutation of serine 265 to alanine resulted in slight increase in auto- and substrate phosphorylations, suggesting that it could be autoinhibitory in function. The other serine residues at positions 165, 181 and 360 did not show any change in the phosphorylation status when compared to wild-type AtSTYPK. In conclusion, this data suggests the importance of serine and threonine residues in the regulation of dual-specificity protein kinase activity and emphasizes the complexity of regulation of dual-specificity protein kinases in plants. To summarise, this study suggests that tyrosine phosphorylation in plants could be brought about only by dual-specificity protein kinases that phosphorylate on serine, threonine and tyrosine residues. This raises an interesting possibility that plants lack classical tyrosine kinases. The results provide a first report of manganese-dependent dual-specificity kinase from plant systems. This data also suggests that plant dual-specificity kinases undergo phosphorylation at multiple amino acid residues and their activity is regulated by various mechanisms, suggesting that they could be regulated by different mechanisms at different stages of plant growth and development. However, the role of dual-specificity kinases in planta has to be understood by mutant analysis in order to assign the physiological roles to these kinases. Further studies are needed to identify the upstream kinase(s) and downstream targets. Determination of physiological functions for dual-specificity protein kinases raises an important challenge in future in the area of plant signal transduction.

The effect of inclusion rate of pea meal (PM), pea protein concentrate (PPC), soybean meal (SBM), soy protein concentrate (SPC), canola meal (CM) and canola protein concentrate (CPC) in salmonid diets was determined through six corresponding meta-analyses of all data available in the literature for these six feed ingredients, which was followed by weighted regression analysis. Increasing dietary inclusion levels of SBM, SPC, CM and CPC reduced specific growth rate (SGR). Regression analysis determined all of these relationships to be linear declines in SGR (P < 0.05). Inclusion levels of PM or PPC did not influence salmonid SGR (P > 0.05). These results showed that the influence plant proteins have on salmonid SGR is dependent on ingredient type and inclusion level. PM, PPC, SBM, SPC, CM an aqueous-extracted CPC and a high phytate CPC (PCPC) were analyzed for chemical nutrient (proximate, amino acid and phosphorus analysis) and antinutrient composition and total tract digestibility (two separate digestibility trials) in rainbow trout (Oncorhynchus mykiss). The digestibility of proximate chemical components and amino acids were significantly higher for the soy products than the pea products. These digestibilities were also significantly higher in protein concentrates than in plant meals. Dry matter and gross energy digestibility was higher in CPC than in CM (P < 0.05). Phosphorus digestibility was higher in CPC-fed fish than in CM-fed fish (P < 0.05), which is likely due to the fact that CPC did not contain phytic acid. Six consecutive growth studies (one trial per test ingredient) were conducted over a 361-day period to determine the effects of feeding increasing inclusion rates of PM, PPC, SBM, SPC, CM and CPC on the growth performance of rainbow trout. Diets were formulated based on the digestible nutrient content of all ingredients as determined in the previously conducted digestibility trials, to contain 0, 75, 150, 225 or 300 g/kg of each test ingredient. All diets were nutritionally equal and contained 17.6 MJ/kg digestible energy, 386.2 g/kg digestible crude protein and were balanced for digestible essential amino acids to meet or exceed the requirements of rainbow trout. Linear and quadratic analysis was conducted on the experimental data. There were no significant regressions resulting from feeding PM, SPC or CPC at 0-300 g/kg for average daily feed intake (ADFI), specific growth rate (SGR), feed conversion ratio (FCR) or protein efficiency ratio (PER). A positive relationship was associated between PPC inclusion and ADFI (P < 0.05). There was a significantly negative quadratic equation associated with the inclusion level of SBM on SGR and FCR and significantly negative linear and quadratic equations for PER. There were significantly negative linear relationships between the inclusion rate of CM and the SGR, FCR and PER of rainbow trout (P < 0.05). Growth trial results suggest at inclusion levels up to 300 g/kg, PM, PPC, SPC and CPC are feasible plant-based fish meal replacements with predictable growth effects, provided the nutritional constraints set in this experiment are followed. The results of these growth experiments were further analyzed using structural equation modeling to determine the relationship between ANF in the six ingredients and ADFI and SGR, which were transformed (tSGR and tADFI, respectively) to enable comparisons between experiments. All possible models between ingredient ANF (starch, phytic acid, glucosinolates, tannins, isoflavones, total NSP, soluble NSP, insoluble NSP and saponins) and ADFI and SGR were calculated. The model with the highest likelihood, as determined by the Akaike Information Criteria0, contained 29 parameters and six degrees of freedom. tADFI positively influenced tSGR. Glucosinolates, saponins, and phytates had a significantly negative impact on tADFI, whereas tannins had a significantly positive impact. The presence of saponins in the diet resulted in a decrease in tSGR. This structural equation model had significant correlations between all ANF, with the exception of phytates and saponins. Future applications of this work will be to develop a nutritional model for optimal inclusion of plant-based feed ingredients in rainbow trout diets, based on their ANF content, which may improve the accuracy of diet formulation and growth prediction.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / Die to rapid growth of aquaculture and the consequent increase for aquaculture feed, the industry's main challenge is to identify potential dietary ingredients that ensure satisfactory performance, economic viability and quality of fish. Considering this demand, the aim of this study was to evaluate the combination of different protein sources on feeding of jundiá juvenile, and their effects on growth, metabolism and quality of fish. Three experiments were conducted. In experiment 1, diets containing alternative protein sources in combination with soybean meal were evaluated: PMM: porcine meat meal; CM: canola meal; SFM: sunflower meal; PBM: poultry by-product meal. After 12 experimental weeks, jundiá fed diets PMM and PBM showed greater weight gain and better feed conversion than those fed diets with plant-protein diets. The enzyme activity, intestinal quotient and somatic indices changed according to the dietary protein source. Fish fed diets PMM and PBM had higher concentrations of plasma triglycerides and cholesterol, and higher fat content in fillet and whole fish, reflecting the higher fat diets. Fish fed diets CM and SFM had lower protein deposition. In the second experiment, the aim was to evaluate the effect of supplementation strategies for limiting amino acids in the diet of jundiá on growth, metabolic response and possible impact on fillet quality. The experimental diets were: CON: porcine meat meal + soybean meal, supplemented with lysine and methionine; MIX: mixture of plant and animal-protein sources, without supplementation of synthetic amino acids; VEG: mixture of plant-protein meals and supplementation with lysine and methionine. At the end of eight weeks trial, there were no significant differences on the performance and fillet composition. However, there were changes in metabolic response of jundiá die to diet composition, which was reflected in body fat content. The VEG diet altered the color and brightness of fillets, although these differences were not detected in the sensory analysis. The third experiment was conducted to evaluate the apparent digestibility coefficients (ADC) of dry matter, organic matter, crude protein, gross energy and fat of the following ingredients: canola meal, porcine meat meal, sunflower meal, soybean meal and poultry by-product meal. Feces were collected in modified Guelph system, using chromium oxide (0.2% in diet) as marker. From the ADC of diets were estimated ADC of ingredients. Porcine meat meal showed the worst digestibility coefficients for all nutritional fractions (about 30%), whereas plant-protein sources showed good digestibility coefficients (between 70 and 80%). Based on the results obtained in this work, we can conclude that: canola meal or sunflower meal in combination with soybean meal in large quantities are not an alternative dietary protein to jundiá; The combination of three plant protein meals, included in small amounts in the diet can provide similar weight gain to that obtained with the CON diet; There is no need for supplementation of free amino acids in diets composed by the combination of vegetable and animal meals in small proportions. / Com o crescimento acelerado da aquicultura e consequente aumento da demanda por rações aquícolas, o principal desafio da indústria consiste em identificar ingredientes potenciais para inclusão nas dietas, que garantam desempenho satisfatório, viabilidade econômica e qualidade do pescado. Considerando esta demanda, o objetivo deste trabalho foi avaliar a combinação de fontes proteicas de origem animal e vegetal na alimentação de juvenis de jundiá, e seus efeitos sobre o crescimento, metabolismo e a qualidade do pescado. Foram conduzidos três experimentos, dois de crescimento e um de digestibilidade. No experimento 1, foram avaliadas dietas contendo fontes proteicas alternativas em combinação com farelo de soja: FCS: farinha de carne suína; FCN: farelo de canola; FGI: farelo de girassol; FVA: farinha de vísceras de aves. Ao final de 12 semanas, os jundiás alimentados com as dietas FCS e FVA apresentaram maior ganho em peso e melhor conversão alimentar que os alimentados com as dietas vegetais. A atividade enzimática, o quociente intestinal e os índices hepato e digestivo-somático foram alterados em função da fonte proteica da dieta. Os peixes alimentados com as dietas FCS e FVA apresentaram maior concentração de triglicerídeos e colesterol plasmáticos, além de maior percentual de gordura no filé e no peixe inteiro, como reflexo do maior teor de gordura nas dietas. Os peixes alimentados com as dietas FCN e FGI apresentaram menor taxa de deposição de proteína corporal e no filé. No segundo experimento, o objetivo foi avaliar o efeito de estratégias de suplementação de aminoácidos limitantes na dieta de jundiás sobre o desempenho zootécnico, resposta metabólica e possíveis reflexos na qualidade dos filés. As dietas avaliadas foram: CON: farinha de carne suína+farelo de soja+suplementação com lisina e metionina; MIX: mistura de farelos vegetais e farinhas animais sem suplementação de aminoácidos livres; VEG: mistura de farelos vegetais e suplementação com lisina e metionina. Ao final de oito semanas, não foram observadas diferenças significativas no desempenho zootécnico e composição dos filés nos diferentes tratamentos. Entretanto, houve alteração da resposta metabólica dos jundiás em função da composição da dieta, que se refletiu no teor de gordura corporal. A dieta VEG alterou a cor e a luminosidade dos filés de jundiá. Entretanto, estas diferenças não foram detectadas na análise sensorial. O terceiro experimento foi realizado para avaliar os coeficientes de digestibilidade aparente (CDA) da matéria seca, matéria orgânica, proteína bruta, energia bruta e gordura dos seguintes ingredientes: farelo de canola, farinha de carne suína, farelo de girassol, farelo de soja e farinha de aves. As fezes foram coletadas em sistema de Guelph modificado, utilizando óxido de cromo (0,2% na dieta). A partir dos CDA das dietas foram estimados os CDA dos ingredientes. A farinha de carne suína apresentou os piores coeficientes de digestibilidade para todas as frações nutricionais (em torno de 30%), enquanto que as fontes proteicas vegetais apresentaram bons coeficientes de digestibilidade (entre 70 e 80%). Com base nos resultados obtidos, pode-se concluir que: Os farelos de canola ou de girassol em combinação com o farelo de soja, em grandes quantidades, não se apresentam como alternativa proteica na dieta de jundiás na fase de recria/engorda; A combinação de farelos vegetais, incluídos em pequenas quantidades na dieta, é capaz de proporcionar ganho em peso semelhante ao obtido com a dieta controle; Não há necessidade de suplementação de aminoácidos livres em dietas compostas pela combinação de farelos vegetais e farinhas animais em pequenas proporções.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Our study tested the inclusion of rice meal protein concentrate (RMPC) in diets containing fish meal, to reduce their use in silver catfish (Rhamdia quelen) nutrition. Were evaluated growth parameters, body composition, deposition of nutrients, metabolic responses and digestive enzymes activities. RMPC was obtained from the Fish Farming Laboratory of the Federal University of Santa Maria, RS. During 45 days, 500 silver catfish juvenile with initial weight of 6.28 ± 0.12 g were average and randomly divided into 20 cylindrical tanks (280 L, each), connected tothermoregulated water recirculation system, two biological filters and ultraviolet filter. The fish were fed three times daily at 9: 00, 13h: 00 to 17h: 00 at apparent satiety, with diets increasing levels of inclusion of RMPC (10, 15, 20, and 30%). At end of the study, we evaluated growth parameters, body composition, nutrient deposition, digestive indices, activities of trypsin and chymotrypsin enzymes, blood parameters and liver. The data were submitted to normality test and analysis of variance and the means were compared with the Control diet by Dunnett test, except weight gain (WG) and specific growth rate (SGR), which were calculated by analysis of cubic regression. Differences were considered significant at probability level of P <0.05. There were no mortalities during the experimental period. Significant differences in body composition, feed conversion, activity of digestive enzymes and plasma parameters of the fish fed with the experimental diets were observed. Significant differences were found for lower final weight and condition factor in fish fed the RMPC10 and RMPC15 diets, as well as lower body protein deposition and daily feed intake in RMPC10 diet. WG and SGR parameters (P = 0.003 and P = 0.004) set up to the cubic regression model, indicating the optimal level of inclusion of RMPC in the diet for maximum growth (25.01% and 25.07% respectively). Fish fed the RMPC30 diet had lower protein efficiency ratio (PER) and hepatossomatic index (HSI) as well as increased activity enzyme alanine aminotransferase. Based on the results obtained, it can be seen that the inclusion of 20% RMPC in diet did not change any of the parameters analyzed in this study, showing growth performance numerically superior to the control and the other diets, demonstrating significant nutritional quality of RMPC. Therefore, adding 20% of RMPC can be used in diets for silver catfish, as an alternative protein ingredient to reduce the use of fishmeal. / Nosso estudo testou a inclusão do concentrado proteico de farelo de arroz (CPFA) em dietas contendo farinha de peixe, visando reduzir seu uso na alimentação de jundiás (Rhamdia quelen). Foram avaliados parâmetros de crescimento, composição corporal, deposição de nutrientes, respostas metabólicas e atividades de enzimas digestivas. O CPFA foi obtido do Laboratório de Piscicultura da Universidade Federal de Santa Maria, RS. Durante 45 dias, 500 juvenis de jundiá com peso médio inicial de 6,28 ± 0,12 g foram distribuídos aleatoriamente em 20 tanques circulares de polietileno (280 L cada), conectados a um sistema de recirculação de água termorregulado dotado de tanque de decantação, dois filtros biológicos, reservatório de água e filtro ultravioleta. Os peixes foram alimentados três vezes ao dia às 9h:00, 13h:00 e 17h:00, até a saciedade aparente com dietas contendo níveis crescentes de inclusão do CPFA (10, 15, 20, e 30%). Ao final do estudo, foram avaliados parâmetros de crescimento, composição corporal, deposição de nutrientes, índices digestórios, atividades das enzimas tripsina e quimotripsina, parâmetros plasmáticos e hepáticos. Os dados foram submetidos a teste de normalidade e análise de variância e as médias foram comparadas com o controle por teste de Dunnett, exceto para ganho de peso (GP) e taxa de crescimento específico (TCE) que foram calculados por análise de regressão cúbica. As diferenças foram consideradas significativas a um nível de probabilidade de P<0,05. Não foram observadas diferenças significativas para composição corporal, conversão alimentar aparente, atividade de enzimas digestivas e parâmetros plasmáticos dos peixes alimentados com as dietas experimentais. Foram encontrados menor peso final e fator de condição nos peixes alimentados com as dietas CPFA10 e CPFA15, além da menor deposição de proteína corporal e consumo diário de ração na dieta CPFA10. Os parâmetros de crescimento GP e TCE ajustaram-se (P = 0,003 e P = 0,004) ao modelo de regressão cúbica, indicando o nível ideal de inclusão do CPFA na dieta para o máximo crescimento (25,01% e 25,07%, respectivamente). Os peixes alimentados com a dieta CPFA30 apresentaram menor taxa de eficiência proteica e índice hepatossomático, além de maior atividade da enzima alanina aminotransferase. Com base nos resultados obtidos, é possível observar que a inclusão de 20% de CPFA na dieta não alterou nenhum dos parâmetros analisados neste estudo, demonstrando desempenho de crescimento numericamente superior ao controle e as demais dietas, demonstrando a significativa qualidade nutricional do CPFA. Portanto, a inclusão de 20% de CPFA pode ser utilizada em dietas para jundiás, como ingrediente proteico alternativo para reduzir o uso da farinha de peixe.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / With the expanding aquaculture activity, high quality ingredients for fish feeding are required. In order to prevent the risk of depending on fish meal, research institutions and the industry itself, have conducted studies to reduce the dependence of fish meal increasing the nutritional value of alternative feedstuffs. The objective of the study was to evaluate different methods of inactivation of antinutritional compounds on nutrient availability of plant protein sources for catfish. The work was divided into three parts: removal of antinutrients, growth trial, and digestibility experiment. In the first part, different chemical treatments for removal of phytic acid, total phenols and tannins in canola, soybean and sunflower meals were tested. The treatments were: acidified water (pH 1.0); ethanol PA + methanol PA; acidified ethanol PA (pH 1.0); ethanol + water PA 70:30 pH 1.0; acidified water + ethanol PA, used separatelly. Washing with pH 1,0 water, followed by washing in ethanol PA was the best alternative for removal of phytic acid, phenols and tannins of canola, sunflower and soybean meal. In the growth experiment were evaluated growth performance, body composition, biochemical parameters, enzymatic profile and intestinal morphometry of juvenile catfish fed with plant ingredients, treated or not treated for removal of antinutrients. Treatments were: control diet, with fish meal as only protein source (CON); replacement of 30% of fishmeal protein by untreated soybean meal (SNT), canola meal (CNT) and sunflower meal (GNT) or the same ingredients submitted to treatment: (ST), (CT) and (GT) (soybean, canola and sunflower, respectively). The treatment is effective, with the exception of phytic acid in soybean meal. ST and CT can replace 30% of fish meal protein, without affecting the growth of animals. There is no difference in the performance of fish fed CT compared to CNT, and GT compared to GNT. For soybean meal, there is improvement in the nutritional value after treatment. The biochemical changes do not appear to be linked to the antinutritional factors. There is no interference of the treatment on the enzymatic activity of silver catfish. Fish fed with untreated ingredients showed enlargement in the thickness of the muscle layer in the intestinal epithelium. The number of villi is higher in fish fed with treated ingredients. There is an increase in the thickness of the lamina propria of the villi in fish fed with the untreated ingredients. In the digestibility experiment, were evaluated the apparent digestibility coefficients (ADCs) of plant ingredients, submitted or not to chemical treatment to remove antinutritional factors in diets for jundiá. The ADC for crude protein was higher in ST, compared to CT and CNT, but did not differ from the others. GNT, GT and CNT showed the lowest ADC for organic matter. The removal of antinutrients do not affect the ADC of crude protein, dry matter and organic matter in soybean and sunflower meal. For canola meal, removing antinutritional factors improve dry matter digestibility. In addition, besides the antinutrients, special care must be taken to concentration or removal of other nutrients when using chemical treatments, otherwise the nutritional value of the ingredient can be affected. / Com a expansão da atividade de aquicultura, surgem também demandas por ingredientes de qualidade para uso em dietas para peixes. Nas últimas décadas, devido à probabilidade de escassez de farinha de peixe, diversas instituições de pesquisa, assim como a própria indústria, têm realizado estudos a fim de reduzir a dependência desta fonte de proteína, através de técnicas para o aumento da qualidade nutricional de ingredientes alternativos à farinha de peixe. Assim, o objetivo do trabalho foi avaliar diferentes métodos de inativação de compostos antinutricionais sobre a disponibilidade de nutrientes de fontes proteicas de origem vegetal para o jundiá. O trabalho foi dividido em três etapas: tratamento dos farelos, experimento de desempenho e experimento de digestibilidade. Na primeira etapa, foi feita a avaliação da eficiência de diferentes tratamentos químicos para remoção de ácido fítico, fenóis totais e taninos totais em farelos de canola, soja e girassol, visando a utilização em dietas para peixes. Os tratamentos foram: água acidificada (pH 1,0); etanol P.A. + metanol P.A. + água; etanol P.A. acidificado (pH 1,0); etanol P.A. + água 70:30 pH 1,0; água acidificada + etanol P.A. utilizados individualmente. O processamento dos farelos através de lavagem com água em pH 1,0, seguido por lavagem em etanol P.A, apresenta comportamento mais uniforme, sendo o mais indicado para a retirada de ácido fítico, fenóis totais e taninos totais dos farelos de canola, girassol e soja. No experimento de crescimento, foram avaliados desempenho zootécnico, composição corporal, parâmetros bioquímicos, perfil enzimático e morfometria intestinal de juvenis de jundiá alimentados com ingredientes vegetais, submetidos ou não a tratamento para remoção de antinutrientes. Os tratamentos foram: dieta controle, à base de farinha de peixe (CON); substituição de 30% da proteína da farinha de peixe por farelos de soja (SNT), canola (CNT) ou girassol (GNT) sem tratamento ou tratados: (ST), (CT) e (GT) (soja, canola e girassol, respectivamente). O tratamento é eficaz na remoção de antinutrientes, com exceção do ácido fítico do farelo de soja. Farelos de soja e canola tratados podem substituir 30% da proteína da farinha de peixe, sem prejudicar o crescimento dos animais. Não há diferença no desempenho de jundiás alimentados com farelo de canola tratado e nãotratado ou girassol tratado e não-tratado. Para farelo de soja, há melhora na qualidade nutricional após tratamento. As alterações bioquímicas não parecem estar ligadas aos fatores antinutricionais presentes. Não há interferência do tratamento sobre a atividade enzimática de jundiás. Peixes alimentados com os farelos não-tratados apresentam camada muscular do epitélio intestinal mais espessa. O número de vilosidades é maior nos peixes alimentados com os farelos tratados. Há aumento na espessura da lamina propria das vilosidades nos peixes alimentados com os farelos não-tratados. No experimento de digestibilidade, foram determinados os coeficientes de digestibilidade aparente dos farelos de canola, girassol e soja, submetidos ou não a tratamento químico para extração de antinutrientes, em dietas para o jundiá. O tratamento para remoção de antinutrientes não afeta os coeficientes de digestibilidade da proteína bruta, matéria seca e matéria orgânica dos farelos de soja e girassol. Para o farelo de canola, a remoção de fatores antinutricionais melhora a digestibilidade da matéria seca. A avaliação de tratamentos para retirada de fatores antinutricionais deve levar em consideração, além da remoção de antinutrientes, a concentração e/ou remoção dos demais nutrientes durante o processo e sua relação com a qualidade nutricional do ingrediente.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work was carried out to evaluate the performance and carcass characteristics of grass carp (Ctenopharyngodon idella) juveniles in response to dietary protein levels and sources. For this, two experiments were conducted: the first (80 days), evaluating four crude protein (CP) levels (22, 30, 36 and 44%) and the second (60 days), comparing protein sources in the diet: FCS (porcine meat meal - control); FC: canola meal; FG: sunflower meal and FCG: canola meal + sunflower meal. Both experiments were conducted in a water re-use system composed of 12 tanks (850 L), with three replicates per treatment. In experiment 1, 10 fish by tank (initial weight 153,0±1,5g) were fed 3% of body weight, twice daily, and the experiment 2 was provided ration (2% of biomass) in the morning and forage (Napier grass ad libitum) in the afternoon, to 15 fish by tank (initial weight 54,6±1,0g). Growth parameters (weight, specific growth rate, daily weight gain, relative weight gain and feed conversion ratio) and carcass (carcass and fillet yield, digestive somatic index, hepatic somatic index and visceral fat index, intestinal quotient, protein retention, protein efficiency rate and whole body and fillet protein and fat deposition) were evaluated. Moreover, the proximate composition (moisture, ash, fat and protein) in fillet and whole fish and blood parameters (glucose, total triglycerides, total cholesterol and total protein in both experiments and hematocrit in Experiment 1) were also evaluated. In experiment 2 was also determined the daily consumption of forage and the instrumental color. In experiment 1, linear positive effect of protein level for all growth variables was observed. However, the same effect was observed to whole body and fillet fat deposition, triglycerides and total cholesterol in serum, indicating that the protein from the diet was used as energy source. To feed conversion ratio and fat in whole fish, the effect was quadratic, with maximum response with 40.6 and 37.1% CP, respectively. Protein retention, protein efficiency ratio, protein deposition in whole body and fillet and hematocrit also showed linear positive effect, while the other parameters were not affected. In experiment 2, the growth parameters and the daily consumption of forage (1.24 to 2.11% of body weight) did not differ among the treatments. About proximate composition of whole fish, higher fat content and lower protein content, besides fillet ash, were obtained in the treatment FCG. The diet FCS presented the highest values of serum protein, triglycerides and total cholesterol. The fillet yield was higher in the treatments FCG and FC, while the digestive somatic index was higher in treatment FG and FCG. In the instrumental evaluation of color, the fillets from FCS and FCG diets showed higher value of L (brightness), differing only treatment FC. The other parameters did not differ among them. Based on this results, we can conclude that: the minimum protein level for maximum growth of grass carp in the growing phase, with practical diets, is 44%; the variation in dietary protein level promotes changes in metabolism of juvenile grass carp, reflected in hematological and carcass parameters; canola meal and sunflower meal can be used in diets for grass carp growing phase, when supplemented with limiting essential amino acids, without compromising growth. / Este trabalho foi conduzido com o objetivo de avaliar o desempenho produtivo e qualidade de pescado de juvenis de carpa capim (Ctenopharyngodon idella) em resposta a níveis e fontes de proteína da dieta. Para isso, foram conduzidos dois experimentos: o primeiro, com 80 dias, avaliando quatro níveis de proteína bruta (22, 30, 36 e 44%) e o segundo, com 60 dias, avaliando fontes protéicas na dieta, em combinação com farelo de soja: FCS: farinha de carne suína; FC: farelo de canola; FG: farelo de girassol e FCG: farelo de canola + farelo de girassol. Ambos os experimentos foram conduzidos em sistema de recirculação de água com temperatura controlada, composto de 12 unidades experimentais (850 L), com três repetições por tratamento. No experimento 1, 10 animais por unidade experimental (peso inicial 153,0 ± 18,2g) foram alimentados com ração (3% da biomassa) duas vezes ao dia. No experimento 2, foram utilizados 15 animais por unidade experimental (peso inicial 54,7 ± 7,8g), alimentados com ração (2% da biomassa) pela manhã e capim elefante (à vontade) à tarde. Foram avaliados os parâmetros de crescimento (peso, taxa de crescimento específico, ganho em peso diário e relativo e conversão alimentar aparente) e de carcaça (rendimento de carcaça e filé, índices digestivossomático, hepatossomático e de gordura visceral, quociente intestinal, coeficiente de retenção protéica e deposições de proteína e gordura corporal e no filé). Além disso, a composição centesimal (umidade, cinzas, gordura e proteína) no filé e no peixe inteiro e os parâmetros sangüíneos (glicose, triglicerídeos totais, colesterol total e proteínas totais nos dois experimentos e hematócrito no experimento 1) também foram avaliados. No experimento 2 também foi determinado o consumo diário de forragem e a medida instrumental da cor. No experimento 1, houve efeito linear positivo do nível de proteína para todas as variáveis de crescimento. Entretanto, o mesmo efeito foi observado para a deposição de gordura corporal e no filé, triglicerídeos totais e colesterol total no soro, indicando que a proteína proveniente da dieta estava sendo utilizada como fonte de energia. Para conversão alimentar aparente e gordura no peixe inteiro, o efeito foi quadrático, com ponto de máxima em 40,6% de PB e 37,1%, respectivamente. Coeficiente de retenção protéica, taxa de eficiência protéica, deposição de proteína corporal e no filé e hematócrito também apresentaram efeito linear positivo. No experimento 2, os parâmetros de crescimento não diferiram estatisticamente entre os tratamentos. O consumo de forragem variou entre 1,24 e 2,11% do PV por dia, não diferindo entre os tratamentos. Na composição centesimal do peixe inteiro, maior teor de gordura e menor teor de proteína foram obtidos no tratamento FCG, bem como para cinzas no filé. A dieta FCS foi a que apresentou maiores valores de proteínas, triglicerídeos e colesterol total circulantes. O rendimento de filé foi maior nos tratamentos FC e FCG, enquanto o índice digestivossomático foi maior nos tratamentos FG e FCG. Na avaliação instrumental da cor, os filés obtidos dos tratamentos FCS e FCG apresentaram maior valor de L (luminosidade), diferindo apenas do tratamento FC. Com base nos resultados obtidos, pode-se concluir que: o nível mínimo de proteína para o máximo crescimento da carpa capim na fase de recria, com dietas práticas, é de 44%; a variação do nível de proteína da dieta promove alterações no metabolismo dos juvenis de carpa capim, refletido nos parâmetros sangüíneos e de carcaça; farelo de canola e farelo de girassol podem ser utilizados em dietas para recria da carpa capim, quando for feita a suplementação com lisina e forragem, sem comprometer o crescimento.

<p>Seme tikve (Cucurbita pepo) obiluje kako uljem tako i proteinima. Nakon izdvajanja ulja, proteini se koncentri&scaron;u u uljanoj pogači, sekundarnom proizvodu procesa proizvodnje ulja, gde njihov sadrţaj dostiţe do 65%. Proteini semena tikve su primamljiv sastojak za prehrambenu, farmaceutsku i kozmetičku industriju zbog svoje farmakolo&scaron;ke aktivnosti i visoke biolo&scaron;ke vrednosti. Pored toga, budući da su mnogi proizvodi ovih industrija po svojoj koloidnoj prirodi emulzije, proteini semena tikve bi se u njima mogli naći i kao prirodne povr&scaron;inski aktivne materije. Međutim, koloidna funkcionalnost proteina semena tikve se jo&scaron; uvek potcenjuje zbog globularne strukture za koju se vezuju slabija funkcionalna svojstva u odnosu na proteine sa fleksibilnijom strukturom. Prema tome, cilj ove disertacije je ispitivanje funkcionalnih osobina proteinskog izolata semena tikve, pre svega njegovih adsorpcionih i emulgujućih svojstava, kao i ispitivanje uticaja promene proteinske strukture putem enzimske hidrolize na ispitivana svojstva.<br />Pripremljeni su izolat proteina semena tikve (IPST) i dva enzimska hidrolizata, H1 i H2. IPST, H1 i H2 su okarakterisani određivanjem sadržaja vlage, proteina i pepela, zatim, određivanjem prinosa, molekulske mase i zeta potencijala. Ispitan je uticaj koncentracije proteina/peptida (0,0001&ndash;1 g/100 cm³), pH (3&ndash;8) i jonske jačine (0&ndash;1 mol/dm³ NaCl) na rastvorljivost i adsorpciona svojstva: dinamički međupovr&scaron;inski pritisak (ulje/voda), statički povr&scaron;inski (vazduh/voda) i međupovr&scaron;inski (ulje/voda) pritisak, kinetiku adsorpcije i dilatacionu reologiju proteinskih adsorpcionih filmova. Nakon toga, ispitan je i uticaj pomenutih parametara na emulziona svojstva IPST, H1 i H2. Emulgujuća svojstva IPST, H1 i H2 su okarakterisana na osnovu prosečnog prečnika kapljica emulzija, raspodele veličina kapljica i stabilnosti emulzija.<br />Utvrđeno je da je prinos IPST veći od prinosa oba hidrolizata za oko 65 %. IPST ima najniţu rastvorljivost na pH=5, &scaron;to ujedno predstavlja i njegovu izoelektričnu tačku. Enzimskom hidrolizom IPST značajno se povećava rastvorljivost, posebno na pI=5. Povećanje jonske jačine je izazvalo salting&ndash;in ili salting&ndash;out efekat rastvorljivosti kod svih uzoraka u zavisnosti od pH. IPST, H1 i H2 poseduju povr&scaron;insku aktivnost pri čemu je povr&scaron;inski/međupovr&scaron;inski pritisak H1 i H2 manje zavistan od promene pH i jonske jačine u poređenju sa povr&scaron;inskim/međupovr&scaron;inskim pritiskom IPST. Adsorpcijom na granicu faza IPST i oba hidrolizata obrazuju adsorpcione filmove sa dominantnom elastičnom komponentom. Emulgujuća svojstva IPST, H1 i H2 zavise od koncentracije uzorka, pH vrednosti i jonske jačine kontinualne faze. Pri koncentraciji od 1 g/100 cm³ i Ic=0 mol/dm³ pripremljene emulzije su stabilne na svim pH osim emulzije IPST na pH 5. Sve emulzije podležu gravitacionoj nestabilnosti.</p> / <p>Pumpkin (Cucurbita pepo) seed is rich source of both, oil and proteins. Once the oil has been extracted, proteins concentrate in oil cake, a by&ndash;product of the oil<br />extraction process, where their content can reach up to 65%. Pumpkin seed proteins are desirable ingredient in food, pharmaceutical and cosmetic industry due to their pharmacological activities and high biological value. Moreover, since many of products of these industries are, in colloidal terms, emulsions, pumpkin seed proteins could serve as surface active materies. However, colloidal functionality of pumpkin seed proteins is still underestimated for their globular structure which entails inferior functional properties to functional properties of proteins with more flexible structure. Based on that, the aim of this dissertation is to investigate functional properties of pumpkin seed protein isolate, adsorption and emulsifying properties, in the first place, and then to investigate the influence of modification of the protein structure, by means of enzymatic hydrolysis, on the aforementioned properties.<br />Pumpkin seed protein isolate, IPST, and two enzymatic hydrolysates, H1 and H2, were prepared. IPST, H1 and H2 were characterized by determination of moisture, ash and protein content, then, by determination of protein recovery, molecular mass and zeta potential. Influence of the protein/peptide concentration (0.0001&ndash;1 g/100 cm³), pH (3&ndash;8) i ionic strength (0&ndash;1 mol/dm³ NaCl) on the solubility and adsorption properties: dynamic interfacial (oil/water) pressure, static surface (air/water) and interfacial (oil/water) pressure, adsorption kinetics and interfacial dilatational properties, was<br />investigated next. In the end, influence of the aforementioned pharameters on the emulsifying properties of IPST, H1 and H2 was investigated. Emulsifying properties of IPST, H1 and H2 were discussed in terms of mean droplet diameter, droplet size distribution and emulsion stability.<br />Protein recovery of IPST was determined to be 65 % higher than recovery of H1 and H2. Solubility of IPST was the lowest at pH 5, what presents the isoelectric point. The enzymatic hydrolysis of IPST significantly increased solubility, especialy at the isoelectric point. Increase in the ionic strenght led to salting&ndash;in or salting&ndash;out effect depending on pH of the sample. Three investigated samples, IPST, H1 and H2 exhibited surface activity, however, sufrace/interfacial pressure of H1 and H2 were found to be less influenced by change in pH or ionic strenght of the solution in comparison to the IPST. Once adsorbed to the interface IPST and both hydrolysates form interfacial film with dominant elastic component. Emulsifying properties of IPST, H1 and H2 depend on the concentration, pH and ionic strength of the continuous phase. Stabile emulsions were formed at concentration of 1 g/100 cm3 and Ic=0 mol/dm³ regardless of pH, with the exception of the IPST at pH 5. All emulsions were susceptibile to gravitational separation.</p>