Obtención de hidrolizados proteicos de leguminosas usando una proteasa recombinante de Pseudomonas aeruginosa M211 / Obtaining protein hydrolysates from leguminous using a recombinant protease from Pseudomonas aeruginosa M211

El género Pseudomonas es una fuente importante de proteasas; sin embargo, su uso está restringido en la industria alimentaria. El clonaje permite aprovechar la capacidad catalítica de estas enzimas mediante su producción en microorganismos inocuos. Por otro lado, las leguminosas son fuentes ricas en proteínas, a partir de las cuales se pueden obtener compuestos con valor agregado mediante procesos de hidrólisis enzimática. En este estudio, se produjo y caracterizó una proteasa recombinante (PT4) alcalina y termoestable de Pseudomonas aeruginosa M211, para la obtención de hidrolizados proteicos de leguminosas. Para ello, el gen de la proteasa se clonó en el vector pJET1.2/blunt utilizando E. coli DHalfa como hospedero. El análisis de la secuencia nucleotídica parcial de la proteasa indicó un 99 % de similitud con Peptidasas de la Familia M4 de Pseudomonas aeruginosa. La enzima recombinante presentó un peso molecular de 80 kDa, demostró ser activa y estable en condiciones alcalinas y termófilas con un pH y temperatura óptimos de 8 y 60 °C, respectivamente, y fue inhibida por EDTA. Además, hidrolizó proteínas de semillas de Glycine max, Phaseolus lunatus, Lupinus mutabilis y Erythrina edulis, obteniéndose fracciones peptídicas menores a 40 kDa. Esta proteasa recombinante se podría utilizar en la elaboración de hidrolizados proteicos funcionales a partir proteínas de distintas fuentes y residuos agroalimentarios.

The genus Pseudomonas is an important source of proteases; however, in the food industry the use of this bacterium is restricted. Cloning allows for the use of the proteolytic activity of Pseudomonas proteases through their production in innocuous microorganisms. Leguminous are protein-rich sources from which value-added compounds can be obtained through enzymatic hydrolysis. In this study, an alkaline and thermostable recombinant protease (PT4) from Pseudomonas aeruginosa M211 was cloned and characterized in order to obtain protein hydrolysates from leguminous. Therefore, protease gene was cloned into the pJET1.2 / blunt vector using E. coli DHalpha as a host. Analysis of protease partial nucleotide sequence showed 99% homology with Peptidases M4 Family from Pseudomonas aeruginosa. The molecular weight of the recombinant enzyme was 80 kDa, it was active and stable under alkaline and thermophilic conditions, presented an optimum pH and temperature of 8 and 60 °C, respectively, and was inhibited by EDTA. In addition, it hydrolysed Glycine max, Phaseolus lunatus, Lupinus mutabilis y Erythrina edulis proteins, obtaining peptide fractions less than 40 kDa. This recombinant protease could be used in the elaboration of functional hydrolysates using protein from different sources and agricultural waste.

Obtención de hidrolizados proteicos bajos en fenilalanina a partir de suero dulce de leche y chachafruto (Erythrina edulis Triana) / Obtaining protein products low in phenylalanine from milk whey and chachafruto (Erythrina edulis Triana)

La fenilcetonuria (PKU) es causada por una actividad deficiente de la enzima fenilalanina hidroxilasa. En los pacientes con esta deficiencia la fenilalanina (Phe) no puede ser convertida en tirosina, aumentando sus niveles en sangre y de otros metabolitos neurotóxicos, provocando un retraso mental irreversible. El tratamiento fundamentalmente se basa en una dieta controlada de Phe. Sin embargo, los alimentos libres o bajos en Phe son escasos. El objetivo de esta investigación es obtener hidrolizados proteicos con bajo contenido de Phe a partir del suero dulce de leche en polvo y harina de E. edulis Triana. El aislado proteico (96,01% proteína cruda) se obtuvo por solubilización y precipitación de las proteínas de la harina, mientras que las proteínas del suero (15,69% proteína cruda) fueron tratadas en su matriz original. Las proteínas del suero y el asilado fueron hidrolizadas enzimáticamente con pepsina y proteasa de Streptomyces griseus. La concentración de Phe se determinó por fluorometría y por HPLC, de lo cual la Phe de las proteínas del suero es liberada una hora antes que las del chachafruto, debido a que las proteínas del suero en parte fueron hidrolizadas en la elaboración del queso. Además, los resultados de la utilización del carbón activados como captor de Phe indican la reducción total del contenido de este aminoácido en los hidrolizados y la reducción de la concentración de otros aminoácidos(AU)

henylketonuria (PKU) is caused by a low activity of the enzyme phenylalanine hydroxylase. In patients with this deficiency, phenylalanine (Phe) cannot be converted to tyrosine, increasing blood levels and other neurotoxic metabolites, causing irreversible mental retardation. The treatment is fundamentally based on a controlled diet of Phe. However, free or low-Phe foods are scarce. The objective of this research is to obtain protein hydrolysates with low Phe content from sweet milk powder and E. edulis Triana flour. The protein isolate (96.01% crude protein) was obtained by solubilization and precipitation of the flour proteins, while the whey proteins (15.69% crude protein) were treated in their original matrix. Serum and asylated proteins were enzymatically hydrolyzed with pepsin and Streptomyces griseus protease. The concentration of Phe was determined by fluorometry and by HPLC, from which the Phe of whey proteins is released one hour earlier than those of chachafruto, due to the fact that the whey proteins were partially hydrolyzed in the elaboration of the cheese. In addition, the results of the use of charcoal activated as Phe captor indicate the total reduction of the content of this amino acid in the hydrolysates and the reduction of the concentration of other amino acids(AU)

Therapeutic effect of brain protein hydrolysate and simvastatin on carotid atherosclerotic plaques in CI patients and its influence on LVEF and CRP level / 心血管康复医学杂志

Objective : To explore clinical value of brain protein hydrolysate (BPH ) and simvastatin in treatment of patients with cerebral infarction (CI) complicated carotid atherosclerotic plaques (CAP).Methods : A total of 90 CI + CAP patients treated in our hospital from Mar 2016 to May 2017 were selected ,randomly and equally divided into routine treatment group and combined treatment group (received simvastatin + BPH based on routine treat-ment) ,both groups were treated for four weeks- Therapeutic effect ,United States National Institutes of Health Stroke Score (NIHSS) ,CAP-related indexes ,hemorheology indexes ,LVEF and CRP before and after treatment and incidence of adverse events were compared between two groups .Results : Compared with routine treatment group after treatment ,there were significant reductions in NIHSS score [ (15-56 ± 6-33) scores vs.(12-14 ± 3-18) scores] ,CAP size [ (1-54 ± 0-32) cm2 vs.(1-34 ± 0-30) cm2 ] ,intima-media thickness [ (1-37 ± 0-08) mm vs. (1-15 ± 0-04) mm] ( P＜0-01 all) ,and significant rise in total effective rate (80-00% vs.95-56%, P＝0-024) in combined treatment group ; there were significant reductions in hematocrit [ (44-24 ± 3-24 )% vs.(37-72 ± 2-41)%] ,platelet aggregation rate [ (45-62 ± 15-95)% vs.(38-10 ± 2-52)%] ,fibrinogen [ (4-06 ± 1-43) g／L vs. (3-18 ± 1-15) g／L] ,whole blood viscosity [ (2-66 ± 0-77) mPa·s vs.(1-55 ± 0-25) mPa·s] ,plasma viscosity [ (1-45 ± 0-11) mPa·s vs.(1-21 ± 0-16) mPa·s] and serum CRP level [ (4-36 ± 1-03) mg／L vs.(1-70 ± 0-20) mg／L] ,and significant rise in LVEF [ (49-30 ± 3-74)% vs.(56-67 ± 4-37)%] in combined treatment group , P＜0-01 all- Incidence rate of cardio-and cerebrovascular events in combined treatment group was significantly lower than that of routine treatment group (4-44% vs.17-18%, P＝ 0-004 ).Conclusion : Simvastatin combined BPH based on routine treatment can achieve better total therapeutic effect and reduce incidence rate of complications in CI + CAP patients .

Influencia del hidrolizado de proteínas en el comportamiento bioproductivo en gallinas de la línea L1 White Leghorn / Influence of protein hydrolysates on bioproduction performance in L1 line White Leghorn hens

RESUMEN El objetivo de la presente investigación fue evaluar la influencia del hidrolizado de proteínas (HP) como suplemento nutricional en el comportamiento bioproductivo en gallinas White Leghorn. Se utilizaron gallinas de reproductores ligeros con 39 semanas de edad, durante seis semanas. Se realizó un diseño completamente aleatorizado con dos tratamientos de 320 gallinas cada uno (tres réplicas de 40 gallinas). El T1, recibió diariamente 2 mL de HP por ave y al T2, no se le ofertó el producto. Se controlaron las variables bioproductivas (producción total de huevos, porcentaje de postura, consumo total de pienso, conversión, viabilidad y la mortalidad por causas), los indicadores de la incubación (huevos a planta, los porcentajes de incubación, incubabilidad y pollitos de primera) y los de calidad (consumo de pienso por pollito de primera y pollitos de primera por gallina). Se observaron diferencias significativas en el porcentaje de postura y significativa para la conversión masal y en los huevos a planta, porcentaje de incubación y porcentaje de incubabilidad y con mejor comportamiento en los indicadores de calidad en las gallinas que recibieron HP. Se concluye que el empleo de HP mejora el porcentaje de postura y la conversión masal y los indicadores relativos a la incubación, porcentaje de huevos aptos a planta, porcentaje de incubación y de incubabilidad de gallinas de la línea ligera, adicionalmente, su uso reduce aproximadamente en 100 gramos el consumo de pienso necesario para obtener un pollito de primera.

ABSTRACT The objective of this study was to evaluate the influence of protein hydrolysates (PH), as a nutritional supplement, in the bioproduction performance of White Leghorn hens. Thirty-nine-week old light line hens were assessed during six weeks. Two treatments (T) were designed involving 320 hens each (three replications of 40 hens each). In T1, each bird received 2 ml of PH daily; the birds in T2 were not offered the product. The following variables were controlled: bioproduction (total egg production, egg-laying percentage, total feed intake, mass conversion, viability, and caused mortality); incubation indicators (eggs to plant, incubation percentage, hatchability, and top quality chicks) and; quality (feed intake by top quality chicks, and top quality chicks per hen). The hens that received the PH showed significant differences in the laying, incubation, and hatchability percentage, as well as mass conversion, and the egg to plant ratio. They showed better performance in quality indicators. It is concluded that the use of PH in light line hens improves their bioproduction performance, as well as the indicators of to incubation, egg to plant ratio, and hatchability; its use also reduces by approximately 100 grams the necessary food intake to obtain top quality chicks.

Aceptabilidad de pre-escolares y escolares a la proteína purificada de pescado en polvo / Acceptability of purified fish-protein powder in pre-school and school age children

RESUMEN Objetivos. Determinar la aceptabilidad de la proteína purificada de pescado (FPi) en bebidas a base de cereales y pseudocereales. Materiales y Métodos. El estudio se realizó en el Centro de Desarrollo Integral Familiar «Año Nuevo¼ del Programa Integral Nacional para el Bienestar Familiar (INABIF), del distrito de Comas en Lima. La FPi (0-4 g por ración) se administró diariamente durante tres meses mezclada en las bebidas a base de cereales y pseudocereales. Se midió la aceptabilidad de la FPi mediante pesado directo en niños menores de 6 años y por escala hedónica facial en escolares (6 a 16 años). Resultados. Se enroló a 158 participantes y se administró de manera supervisada 4211 desayunos. El aporte calórico de las bebidas a base de cereales y pseudocereales luego de adicionar la FPi estuvo entre 117 y 140 Kcal y el aporte proteico entre 3,4 y 5,4 g por ración. La aceptabilidad en los niños mayores de 6 años de las bebidas suplementadas con la FPi (juntando los dos mayores puntajes) estuvo entre 55-74 % para la avena, alrededor del 47 % para la quinua y entre 40-58 % para la kiwicha. Mientras que el 90 % de los niños menores de 6 años consumieron más del 70 % de lo ofrecido. Conclusiones. Se encontró una buena aceptabilidad de la FPi en las bebidas a base de cereal y pseudocereales en menores de 6 años. La FPi es una alternativa para mejorar el aporte de proteínas de origen animal en los niños, sobre todo en los preescolares.

ABSTRACT Objective. To determine the acceptability of purified fish protein (FPi) in cereal and pseudocereal-based drinks. Materials and Methods. The study was carried out at Centro de Desarrollo Integral Familiar "Año Nuevo" belonging to the INABIF Program in the district of Comas in Lima. FPi (0-4 g per serving) was administered daily for 3 months mixed with cereal and pseudocereal-based drinks. The acceptability of FPi was measured by direct weighing in children under 6 years of age and by the hedonic facial scale in school-age children. Results. One hundred and fifty-eight (158) participants were enrolled and 4,211 breakfasts were served. The caloric intake of the cereal and pseudocereal drinks, after adding the FPi, ranged between 117 and 140 Kcal, and protein intake ranged between 3.4 g and 5.4 g per serving. The acceptability of drinks supplemented with FPi in children older than 6 years of age (the 2 highest scores together) ranged from 55% to 74% for oats, around 47% for quinoa and 40% to 58% for "kiwicha" (amaranth). Whereas 90% of children under 6 consumed more than 70% of the drinks offered. Conclusions. We found a good acceptability of FPi in cereal and pseudocereal beverages in children under 6 years of age. FPi is an alternative to improve the consumption of animal protein in the nutrition of children, especially in pre-schoolers.

Types of Special Infant Formulas Marketed in Korea and Their Indications / 대한소아소화기영양학회지

Infant formula is classified into standard cow's milk-based and special formulas. This review aimed at summarizing the types of special milk formulas currently sold in Korea, and the appropriate indications for the use of these formulas; lactose free formula, soy-based formula, protein hydrolysate formula, amino acid-based formula, preterm formula, medium chain triglyceride formula, low-phosphorus formula, protein-energy-enriched formula, and formulas for inborn errors of metabolism.

Antihypertensive effect of an enzymatic hydrolysate from Styela clava flesh tissue in type 2 diabetic patients with hypertension

BACKGROUND/OBJECTIVES: In this randomized, placebo-controlled, double-blind study, we evaluated the antihypertensive effects of enzymatic hydrolysate from Styela clava flesh tissue in patients with type 2 diabetes mellitus (T2DM) and hypertension. SUBJECTS/METHODS: S. clava flesh tissue hydrolysate (SFTH) (n = 34) and placebo (n = 22) were randomly allocated to the study subjects. Each subject ingested two test capsules (500 mg) containing powdered SFTH (SFTH group) or placebo capsules (placebo group) during four weeks. RESULTS: In the SFTH group, systolic and diastolic blood pressure decreased significantly 4 weeks after ingestion by 9.9 mmHg (P < 0.01) and 7.8 mmHg (P < 0.01), respectively. In addition, the SFTH group exhibited a significant decrease in hemoglobin A1c with a tendency toward improvement in homeostasis model assessment of insulin resistance, triglyceride, apolipoprotein B and plasma insulin levels after 4 weeks. No adverse effects were observed in other indexes, including biochemical and hematological parameters in both groups. CONCLUSION: The results of our study suggested that SFTH exerts a regulatory, antihypertensive effect in patients with T2DM and hypertension.

Solid-state fermentation of Acanthogobius hasta processing by-products for the production of antioxidant protein hydrolysates with Aspergillus oryzae

Functional properties and antioxidative activity of a protein hydrolysate prepared from Acanthogobius hasta processing by-product protein during solid-state fermentation with Aspergillus oryzae were investigated. Overall, protease activity increased with the degree of hydrolysis (DH) decreased during solid-state fermentation. All the protein hydrolysate had excellent solubility, possessed interfacial properties, and varying degrees of antioxidant activity which were governed by their concentrations and DH, molecular weight distribution and amino acid composition. After 5 days fermentation, the DH of the protein hydrolysate was 31.23%. The protein hydrolysate had the highest total hydrophobic amino acid content, the highest DPPH scavenging activity, reducing power, and the chelating activity. The radical-scavenging activity of the hydrolysates at 6 mg/mL was 78.6%. The reducing power of protein hydrolysate at the range of 0-6 mg/mL was lower than that of BHA at the range of 0-60 µg/mL, while the chelating activity of APs was similar to that of BHA at the range of 0-60 µg/mL. Moreover, the protein hydrolysate showed good emulsifying and foaming properties over a wide pH range from 2 to 12. Therefore, solid state fermentation provided a suitable and low-cost method for converting Acanthogobius hasta processing by-product protein into antioxidant protein hydrolysates.

Action of a pancreatin and an Aspergillus oryzae protease on whey proteins: correlation among the methods of analysis of the enzymatic hydrolysates

The objectives of this study were to hydrolyze whey proteins using a pancreatin and an Aspergillus oryzae protease; to evaluate the degree of hydrolysis (DH) and the peptide profile; and to establish the correlations among the analytical methods. Ten hydrolysates were prepared at different reaction times and the highest DH was obtained by the protein content method. Good correlations (r > 0.87) between the methods of formaldehyde and orthophthalaldehyde (OPA), formaldehyde and osmometry as well as osmometry and OPA were observed using pancreatin. Similar results were obtained between OPA and soluble protein content for the A. oryzae protease. The action of pancreatin produced the highest contents of di- and tripeptides (9.07, 7.12 and 6.46%) and the lowest of large peptides (42.43, 41.33 and 41.13%), after 3, 4 and 5 h of hydrolysis, respectively. Using pancreatin, the DH measured by formol titration and OPA was positively correlated with medium peptide content and negatively correlated with large peptide content. For the A. oryzae protease, a strong negative correlation was observed between the large peptide content and the DH measured by the OPA method.

Inhibición de la Enzima Convertidora de Angiotensina I con hidrolizados proteicos de Jatropha curcas / Angiotensin I-Converting Enzyme inhibition with protein hydrolysates from Jatropha curcas / Inibição da Enzima Conversora de Angiotensina I com hidrolisados proteicos de Jatropha curcas

Se evaluó la actividad inhibitoria in vitro de los hidrolizados proteínicos obtenidos a partir de la harina desgrasada y del aislado proteínico provenientes del grano de Jatropha curcas L. sobre la actividad de la enzima convertidora de angiotensina I (ECA-1), con la finalidad de emplearlos en un futuro para la formulación de alimentos funcionales. Los hidrolizados fueron obtenidos empleando alcalasa y el sistema enzimático pepsina-pancreatina. Se calculó la concentración media inhibitoria (IC50) para medir el grado de inhibición de la actividad enzimática de ECA-1. Fueron seleccionados los hidrolizados con el menor tiempo de hidrólisis (60 min) para evaluar la bioactividad, dado que las cinéticas de hidrólisis enzimática de la harina desgrasada y del aislado proteínico no encontraron diferencias significativas en el grado de hidrólisis para los tiempos de reacción en cada sistema (60, 90 y 120 min). Los valores de IC50 que presentaron el mejor efecto de inhibición sobre la ECA-I fueron 2,8 y 7,0 µg/mL, obtenidos a partir del aislado proteínico con la enzima alcalasa y con el sistema secuencial pepsina-pancreatina, respectivamente. Los hidrolizados de J. curcas podrían ser incorporados en la elaboración de alimentos funcionales y ser aplicados en tratamientos para personas con hipertensión por su efecto inhibitorio sobre la ECA-I.

In vitro angiotensin I-converting enzyme (ACE) inhibitory activity was evaluated in protein hydrolysates from defatted meal and protein isolate from Jatropha curcas L. Seed, in order to determine their potential inclusion in functional food formulation. Hydrolysates were produced using Alcalase® or a sequential pepsin-pancreatin enzymatic system. Mean inhibitory concentration (IC50) was used to measure the degree of ACE enzymatic activity inhibition. Bioactivity was evaluated in the hydrolysates with the lowest hydrolysis time (60 min) given that no differences in degree of hydrolysis in terms of reaction time in each system were observed (60, 90 and 120 min) in the enzymatic hydrolysis kinetics for the defatted meal and protein isolate. The protein isolate exhibited the highest inhibitory effect, as seen in the IC50 values: 2.8 µg/mL in the alcalase system and 7.0 µg/mL in the pepsin-pancreatin system. Hydrolysates from J. curcas seed exhibit ACE inhibition and could be incorporated into functional foods or treatments for those suffering hypertension.

Foi avaliada a atividade inibitória in vitro dos hidrolisados proteicos obtidos a partir da farinha desengordurada e do isolado proteico provenientes do grão de Jatropha curcas L. sobre a atividade da enzima conversora de angiotensina I (ECA-1), com o objetivo de utilizá-los num futuro para a formulação de alimentos funcionais. Os hidrolisados foram obtidos usando alcalase e o sistema enzimático pepsina-pancreatina. Foi calculada a concentração média inibitória (IC50) para medir o grau de inibição da atividade enzimática da ECA-1. Foram selecionados os hidrolisados com o menor tempo de hidrólise (60 min.) para avaliar a bioatividade visto que as cinéticas de hidrólise enzimática da farinha desengordurada e do isolado proteico não encontraram diferenças significativas no grau de hidrólise para os tempos de reação para cada sistema (60, 90 e 120 min.). Os valores de IC50 que apresentaram o melhor efeito de inibição sobre a ECA-I foram 2.8 e 7.0 µg/mL obtidos a partir do isolado proteico com a enzima alcalase e com o sistema sequencial pepsina-pancreatina respectivamente. Os hidrolisados de J. curcas poderiam ser incorporados na elaboração de alimentos funcionais e ser aplicados em tratamentos para pessoas com hipertensão por seu efeito inibitório sobre a ECA-I.

Analysis of whey protein hydrolysates: peptide profile and ACE inhibitory activity

The aim of this study was to prepare enzymatic hydrolysates from whey protein concentrate with a nutritionally adequate peptide profile and the ability to inhibit angiotensin-converting enzyme (ACE) activity. The effects of the type of enzyme used (pancreatin or papain), the enzyme:substrate ratio (E:S ratio=0.5:100, 1:100, 2:100 and 3:100) and the use of ultrafiltration (UF) were investigated. The fractionation of peptides was performed by size-exclusion-HPLC, and the quantification of the components of the chromatographic fractions was carried out by a rapid Corrected Fraction Area method. The ACE inhibitory activity (ACE-IA) was determined by Reverse Phase-HPLC. All parameters tested affected both the peptide profile and the ACE-IA. The best peptide profile was achieved for the hydrolysates obtained with papain, whereas pancreatin was more advantageous in terms of ACE-IA. The beneficial effect of using a lower E:S ratio on the peptide profile and ACE-IA was observed for both enzymes depending on the conditions used to prepare the hydrolysates. The beneficial effect of not using UF on the peptide profile was observed in some cases for pancreatin and papain. However, the absence of UF yielded greater ACE-IA only when using papain.

O objetivo deste estudo foi preparar hidrolisados enzimáticos do concentrado proteico do soro de leite com perfil peptídico nutricionalmente adequado e com capacidade para inibir a atividade da enzima conversora da angiotensina (ECA). Os efeitos do tipo de enzima usado (pancreatina ou papaína), da relação enzima:substrato (E:S=0,5:100, 1:100, 2:100 e 3:100) e do uso da ultrafiltração (UF) foram investigados. O fracionamento dos peptídeos foi feito por CLAE de exclusão molecular e a quantificação dos componentes das frações cromatográficas foi realizada pelo método da Área Corrigida da Fração. A atividade inibitória da ECA (AI-ECA) foi determinada por CLAE de fase reversa. Todos os parâmetros testados afetaram tanto o perfil peptídico quanto a AI-ECA. O melhor perfil peptídico foi atingido para os hidrolisados obtidos com papaína, enquanto a pancreatina foi mais vantajosa em termos da AI-ECA. O efeito benéfico do uso de menor relação E:S sobre o perfil peptídico e a AI-ECA foi observado para ambas as enzimas dependendo das condições usadas para o preparo dos hidrolisados. O efeito benéfico da ausência da UF sobre o perfil peptídico foi observado em alguns casos para pancreatina e papaína. No entanto, a ausência da UF produziu maior AI-ECA somente quando a papaína foi usada.

Relationship between oxidative protein damage and serum matrix metalloproteinase-2 in diabetic nephropathy / 中国医师杂志

Objective Serum indicators of oxidative protein damage (OPD) were analyzed to explore the effect on renal MMP/TIMP system of OPD in diabetic nephropathy. Methods AOPP levels and PCO levels were measured by modified Witko-Sarsat's method and 2, 4-dinitrophenylhydrazine spectrophotometric method, expression of serum MMP-2 were determined by ELISA, and MMP-2 activity were detected by zymography . Results AOPP levels of group DN1, group DN2 were higher than those of group DM(78.23±19.30 vs 61.25±12.13,101.59±30.22 vs 61.25±12.13,F＝41.988,P＜0.01). PCO levels of group DN1 and group DN2 were higher than those of group DM (0.84±0.03 vs 0.66±0.02,1.05±0.05 vs 0.66±0.02,F＝205.763,P＜0.01). Pearson correlation analysis indicated AOPP and PCO were positively correlated with the expression (r＝0.460,0.480,P＜0.05) and activity (r＝0.385,0.560,P＜0.05) of serum MMP-2. Multiple stepwise regression analysis showed that AOPP and PCO were major influential factors of serum MMP-2 expression (P＜0.05,P＜0.01) and activity(P＜0.01,P＜0.05). Conclusions OPD might be involved in the imbalance of renal matrix metabolism, which was correlated with the development of diabetic nephropathy.

Ação de fatores enzimáticos na obtenção de hidrolisados protéicos de farinha de trigo com baixo teor de fenilalanina / Action of enzymatic factors in obtaining protein hydrolysates of wheat flour, low-phenylalanine

Visando ao preparo de farinha de trigo com baixo teor de fenilalanina (Phe), extraiu-se, enzimaticamente as proteínas, empregando-se uma protease alcalina de Bacillus licheniformis. Em seguida, os extratos protéicos foram hidrolisados pela ação de enzimas comerciais (pancreatina e bromelina) e de extratos enzimáticos obtidos da casca de abacaxi (bruto e purificado), avaliando-se alguns parâmetros enzimáticos, tais como tipo de enzima, tipo de ação enzimática, tipo de associação enzimática e ordem de ação enzimática. O carvão ativado (CA) foi empregado como meio adsorvente e a eficiência da remoção de Phe foi avaliada por espectrofotometria derivada segunda, determinando-se o teor de Phe na farinha de trigo e em seus hidrolisados, após tratamento com CA. O melhor resultado foi encontrado ao se empregar a associação sucessiva do extrato bruto seguida da pancreatina, tendo atingido 66,28 por cento de remoção e o teor final de Phe de 522,44 mg/100 g de hidrolisado.

With the aim of producing wheat flour with low phenylalanine (Phe) content to be introduced in phenylketonuric's diet, the proteins were enzymaticaly extracted, using an alkaline protease from Bacillus licheniformis. Then, the protein extracts were hydrolyzed by the action of commercial enzymes (pancreatin and bromelain) and of enzymatic extracts obtained from pineapple peel (crude and purified). Some enzymatic parameters were evaluated, such as type of enzyme, type of enzyme action, type of enzymatic association and order of enzyme action. The activated carbon (AC) was used as adsorbent and the efficiency of Phe removal was evaluated by second derivative spectrophotometry measuring the Phe content in wheat flour and in their hydrolysates after AC treatment. The best result was found for the successive association of crude extract followed by pancreatin obtaining 66.28 percent of removal and a final Phe content of 522.44 mg/100 g of hydrolysate.

THE COMPARATIVE STUDY ON ANTIHYPERTENSIVE EFFECTS OF THREE ISOLATED VEGETABLE PROTEIN HYDROLYSATES PREPARED WITH ALCALASE / 营养学报

Objective:To investigate the antihypertensive effects of mung bean protein,peanut protein and rice protein alcalase hydrolysates with in vitro angiotensin I-converting enzyme(ACE) inhibitory activity in spontaneously hypertensive rats(SHR) . Method:The impact of digestive proteases on ACE inhibitory activity of hydrolysates of peanut,mung bean and rice protein isolates were evaluated under simulated gastrointestinal digestion and their antihypertensive effects were investigated in SHR after single oral administration. Results:All of three kinds of protein hydrolysates showed antihypertensive activities after single oral administration at a dose of 600 mg/kg bw,most potent in mung bean protein while least in peanut protein. There were no significant changes in the heart rate of SHR after oral administration of protein hydrolysates. Conclusion:Mung bean protein,peanut protein and rice protein hydrolysates all showed antihypertensive activity,but their potent inhibitory activities on ACE did not correlate with their antihypertensive activities found in SHR.

Short-term Effect of Partially Hydrolyzed Formula on the Prevention of Development of Atopic Dermatitis in Infants at High Risk

This short-term, prospective study was aimed to assess the effects of partially hydrolyzed formula (PHF) on the prevention of the development of atopic dermatitis in infants at high risk. The infants of parents with allergy symptoms and serum total IgE over 200 kU/L were divided into 3 groups by their feeding patterns: PHF group (n=15), standard formula (SF) group (n=32), and breast milk (BM) group (n=22). No allergenic food was given during the study period of 6 months, and breastfeeding mothers avoided egg ingestion. Their atopic symptoms were monitored every 2 months. The cumulative incidence and prevalence of atopic dermatitis at the age of 6 months were significantly less in the PHF group than in the SF group (47% vs.78%, p<0.05; 20% vs. 59%, p<0.05). Those rates of the PHF group were also less than those of the BM group, but they were not statistically significant. There was no difference in the onset age and disease severity. These results suggest that early feeding of PHF to infants at high risk has a short-term preventive effect on the development of atopic dermatitis during the first 6 months of life. Long-term preventive effects should be evaluated.

Cysteine and arginine in plasma albumin are the major targets attacked by free radicals / 中华肾脏病杂志

Objective To study the effects of oxidants on the structure of albumin. Methods Using both AOPPs and protein carbonyl content as indices. The oxidative stress level in normal controls and uremia patients was evaluated. Albumin in plasma was purified by HPLC and then was subjected to amino acids composition assay. Results Both AOPPs level and protein carbonyl content in uremic patients were significantly higher than those in controls (P

Obtención de la toxina tetánica a partir de hidrolizado de caseina de producción nacional

La producción de toxoide tetánico se realiza a partir de la toxina tetánica destoxificada y purificada por métodos químicos. Un buen rendimiento de la toxina tetánica reviste gran importancia, pues éste es fundamental para obtener el número de dosis necesarias a un bajo costo. Se presentan los resultados obtenidos en la producción de toxina tetánica a partir de hidrolizado de caseína de producción nacional, mediante la realización de pruebas químicas, microbiológicas e inmunológicas, y se comprueba que el rendimiento es superior al obtenido con el hidrolizado de caseína de importación (triptona T, Oxoid).

The production of the tetanus toxoid is developed from the chemically detoxified and purified tetanus toxin. A good yielding of the tetanus toxin has a great importances, since it is fundamental to obtain the amount of necessary doses at a low cost. Here the authors present the results of the production of the tetanus toxin from the nationally produced casein hydrolysate, through chemical, microbiological, and immunological tests, and it is confirmed that the yield is higher than the one obtained with the imported casein hydrolysate (triptone T, Oxoid).