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1.
Bioprocess Biosyst Eng ; 44(6): 1109-1118, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33547961

RESUMEN

Isomaltulose is an alternative sugar obtained from sucrose using some bacteria producing glycosyltransferase. This work aimed to optimize conditions for the immobilization of Serratia plymuthica through ionic gelation and cross-linking by transglutaminase using the sequential experimental strategy for the conversion of sucrose into isomaltulose. The effect of five variables (concentrations of cell mass, alginate, gelatin, transglutaminase, and calcium chloride) was studied, as well as the interactions between them on the matrix composition for the S. plymuthica immobilization. Three experimental designs were used to optimize the concentrations of each variable to obtain higher concentration of isomaltulose. A high conversion of sucrose into isomaltulose (71.04%) was obtained by the cells immobilized in a matrix composed of alginate (1.7%), CaCl2 (0.25 mol/L), gelatin (0.5%), transglutaminase (3.5%) and cell mass (33.5%). As a result, the transglutaminase application as a cross-linking agent improved the immobilization of Serratia plymuthica cells and the conversion of sucrose into isomaltulose.


Asunto(s)
Células Inmovilizadas , Reactivos de Enlaces Cruzados/química , Isomaltosa/biosíntesis , Serratia , Sacarosa/metabolismo , Transglutaminasas/química , Células Inmovilizadas/química , Células Inmovilizadas/metabolismo , Serratia/química , Serratia/metabolismo
2.
Meat Sci ; 174: 108421, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33429336

RESUMEN

The present study investigated the effect of the enzymes papain (0.2%) and microbial transglutaminase (MTG) (1%) on the texture properties of beef and chicken burgers to develop a meat product with significant increase in softness due to the physiological limitations of the elderly. The products were characterized for pH, objective color, water activity, texture profile analysis (TPA), shear force, compression test, electrophoretic profile, cooking loss, and diameter reduction. A pronounced increase in softness was observed for both raw materials containing papain. An increase in shear force was observed for the beef burger containing only MTG, while the chicken burger showed a reduction of this parameter. The compression tests showed papain alone or combined with MTG decreased the hardness of the burgers. The results showed that the combination of the enzymes papain and MTG can be an effective strategy to develop beef and chicken burgers much softer, contributing to the future studies focused on the physiological needs of the elderly.


Asunto(s)
Productos de la Carne/análisis , Papaína/química , Resistencia al Corte , Transglutaminasas/química , Animales , Bovinos , Pollos , Culinaria , Manipulación de Alimentos/métodos , Dureza
3.
PLoS One ; 15(1): e0227866, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31945132

RESUMEN

A purple cactus pear (Opuntia ficus-indica) extract (CP) was encapsulated in double emulsions (DE) gelled with gelatin (DE-CP-G) and with gelatin and transglutaminase (DE-CP-GT), as well as in a DE with a liquid external aqueous phase (DE-CP), in order to study the retention of betanin as colorant agent. Both gelled DEs showed a predominantly elastic behavior, in contrast with DE-CP. The degradation rate constant of betanin was significantly higher in DE-CP-GT (90.2 x 10-3 days-1) than in DE-CP-G (11.0 x 10-3 days-1) and DE-CP (14.6 x 10-3 days-1) during cold-storage (4 °C). A shift towards yellow color was found in all the systems during cold-storage (4 °C) and after thermal treatment (70°C/30 min), especially in DE-CP-GT, denoting a higher degradation of betanin. Betalamic acid, cyclo-Dopa 5-O-ß-glucoside, 17-decarboxy-betanin and neobetanin were identified by UHPLC-MS/MS as degradation products of betanin.


Asunto(s)
Betacianinas/química , Geles/química , Opuntia/química , Extractos Vegetales/química , Betalaínas/química , Betalaínas/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Emulsiones/química , Frutas/química , Pigmentos Biológicos/química , Piridinas/química , Piridinas/aislamiento & purificación , Espectrometría de Masas en Tándem , Transglutaminasas/química
4.
Int J Biol Macromol ; 144: 536-543, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31862362

RESUMEN

The effect of high-intensity ultrasound (US) combined with transglutaminase treatment (TG) and the inclusion of nanoparticles (Np) on the structural, mechanical, barrier, and physicochemical properties of quinoa protein/chitosan composite edible films were evaluated. Structurally it was observed that the maximum temperatures of the thermal degradation increased with the use of combined US and TG treatment, generating films with superior thermal stability. FTIR results showed that in the amide zone I oscillations of the polypeptide structure were related to the stretching vibrations of CO in the US/TG-Np edible film. Which has generally been associated with changes in the structure and formation of covalent bonds by the action of TG. The US improved mechanical properties by increasing the tensile strength (with or without the application of TG). While combining US-TG produced a significant increase in thickness, decrease in elongation percentage, and increase in tensile strength. Which can be attributed to cross-linking produced by TG. Water vapour permeability increased in all cases. In general, the combination of US-TG treatments showed a more pronounced effect on the structure and mechanical properties.


Asunto(s)
Chenopodium quinoa/química , Quitosano/química , Películas Comestibles , Nanopartículas/química , Transglutaminasas/química , Ondas Ultrasónicas
5.
J Microencapsul ; 35(2): 165-180, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29513057

RESUMEN

Orange essential oil was microencapsulated by complex coacervation with whey protein isolate (WPI): carboxymethylcellulose (CMC), WPI:sodium alginate (SA) and WPI:chitosan (CH). Effect of pH, protein:polysaccharide ratio and solid concentration on coacervation efficiency were selected for the best coacervation conditions. Tannic acid (TA), sodium tripolyphosphate, oxidised tannic acid and transglutaminase enzyme (TG) were used as cross-linking agents. Highest encapsulation efficiency (EE) for wet coacervated microcapsules ranged from 88% to 94%. Microcapsules were freeze and spray dried to evaluate their effect on its integrity. EE was higher than 80% in freeze dried coacervated microcapsules with and without cross-linking agent, but they formed a solid cake. Spray-dried samples formed a free fluid solid (10-20 µm), where the systems WPI:CMC and WPI:CH cross-linked with TA and TG, respectively showed the highest EE (47% and 50% respectively), representing 400% improvement compared to the samples without cross-linking.


Asunto(s)
Reactivos de Enlaces Cruzados/química , Aceites Volátiles/administración & dosificación , Aceites de Plantas/administración & dosificación , Polisacáridos/química , Proteína de Suero de Leche/química , Cápsulas/química , Citrus sinensis/química , Desecación/métodos , Composición de Medicamentos/métodos , Liofilización/métodos , Aceites Volátiles/química , Oxidación-Reducción , Aceites de Plantas/química , Polifosfatos/química , Taninos/química , Transglutaminasas/química
7.
Appl Biochem Biotechnol ; 170(5): 1057-65, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23640262

RESUMEN

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


Asunto(s)
Reactores Biológicos/microbiología , Streptomyces/clasificación , Streptomyces/enzimología , Transglutaminasas/biosíntesis , Transglutaminasas/química , Brasil , Especificidad de la Especie , Temperatura , Transglutaminasas/aislamiento & purificación
8.
Clinics (Sao Paulo) ; 67(10): 1171-9, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23070344

RESUMEN

OBJECTIVE: To explore the use of ß-lactoglobulin polymerized using microbial transglutaminase and heating to identify whether protein polymerization could reduce in vivo allergenicity and maintain in vitro and ex vivo immunoreactivity for use in tolerance-induction protocols. METHODS: Based on previous protocols applied in mice and children, we performed in vivo challenges (using a skin prick test) with native and polymerized ß-lactoglobulin in adult patients with an IgE-mediated allergy to plactoglobulin. In vitro humoral immunoreactivity was analyzed using immunoblotting. Cell-mediated immunoreactivity was analyzed using ex vivo challenges with native and polymerized ß-lactoglobulin and monitored by leukocyte adherence inhibition tests. RESULTS: The skin tests demonstrated that there was a significant reduction in immediate cutaneous reactivity after polymerization. Polymerization did not decrease the immunoblotting detection of s-IgE specific to ß-lactoglobulin. Cell-mediated immunoreactivity, as assessed by ex vivo challenges and leukocyte adherence inhibition tests, did not exhibit significant differences between leukocytes challenged with native versus polymerized ß-lactoglobulin. CONCLUSIONS: The polymerization of ß-lactoglobulin decreased in vivo allergenicity and did not decrease in vitro humoral or ex vivo cell-mediated immunoreactivity. Therefore, we conclude that inducing polymerization using transglutaminase represents a promising technique to produce suitable molecules for the purpose of designing oral/ sublingual tolerance induction protocols for the treatment of allergies.


Asunto(s)
Cisteína/inmunología , Tolerancia Inmunológica/inmunología , Lactoglobulinas/inmunología , Hipersensibilidad a la Leche/inmunología , Transglutaminasas/inmunología , Adolescente , Adulto , Anciano , Alérgenos/inmunología , Estudios de Casos y Controles , Cisteína/química , Femenino , Calefacción , Humanos , Immunoblotting , Inmunoglobulina E/sangre , Prueba de Inhibición de Adhesión Leucocitaria , Masculino , Persona de Mediana Edad , Hipersensibilidad a la Leche/prevención & control , Polimerizacion , Pruebas Cutáneas , Estadísticas no Paramétricas , Transglutaminasas/química , Adulto Joven
9.
Clinics ; Clinics;67(10): 1171-1179, Oct. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-653481

RESUMEN

OBJECTIVE: To explore the use of β-lactoglobulin polymerized using microbial transglutaminase and heating to identify whether protein polymerization could reduce in vivo allergenicity and maintain in vitro and ex vivo immunoreactivity for use in tolerance-induction protocols. METHODS: Based on previous protocols applied in mice and children, we performed in vivo challenges (using a skin prick test) with native and polymerized β-lactoglobulin in adult patients with an IgE-mediated allergy to plactoglobulin. In vitro humoral immunoreactivity was analyzed using immunoblotting. Cell-mediated immunoreactivity was analyzed using ex vivo challenges with native and polymerized β-lactoglobulin and monitored by leukocyte adherence inhibition tests. RESULTS: The skin tests demonstrated that there was a significant reduction in immediate cutaneous reactivity after polymerization. Polymerization did not decrease the immunoblotting detection of s-IgE specific to β-lactoglobulin. Cell-mediated immunoreactivity, as assessed by ex vivo challenges and leukocyte adherence inhibition tests, did not exhibit significant differences between leukocytes challenged with native versus polymerized β-lactoglobulin. CONCLUSIONS: The polymerization of β-lactoglobulin decreased in vivo allergenicity and did not decrease in vitro humoral or ex vivo cell-mediated immunoreactivity. Therefore, we conclude that inducing polymerization using transglutaminase represents a promising technique to produce suitable molecules for the purpose of designing oral/ sublingual tolerance induction protocols for the treatment of allergies.


Asunto(s)
Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Cisteína/inmunología , Tolerancia Inmunológica/inmunología , Lactoglobulinas/inmunología , Hipersensibilidad a la Leche/inmunología , Transglutaminasas/inmunología , Alérgenos/inmunología , Estudios de Casos y Controles , Cisteína/química , Calefacción , Immunoblotting , Inmunoglobulina E/sangre , Prueba de Inhibición de Adhesión Leucocitaria , Hipersensibilidad a la Leche/prevención & control , Polimerizacion , Pruebas Cutáneas , Estadísticas no Paramétricas , Transglutaminasas/química
10.
Electron. j. biotechnol ; Electron. j. biotechnol;10(4): 618-626, oct. 2007. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-504114

RESUMEN

Finding a new microbial source of transglutaminase (MTGase) and the study of the medium composition for MTGase production were the goals of this work. A total of 200 actinomycete-like strains were isolated from Brazilian soil samples and two of them named T10b and P20 were selected based on their ability to produce 0.15 U.mL-1 and 0.25 U.mL-1 of MTGase, respectively. Strain P20 was chosen to continue the study and was identified as Streptomyces sp. In order to optimize the MTGase activity, modifications of the usual media composition described for enzyme production were tested. The strategy adopted was: (1) screening experiment for the best carbon and nitrogen sources; (2) fractional factorial design (FFD) to elucidate the key ingredients in the media (the results indicated that the soybean flour, peptone, KH2PO4 and MgSO4.7H2O had a significant effect on MTGase) production and (3) central composite design (CCD) to optimize the concentration of the key components. The experimental results were fitted to a second-order polynomial model at the 95 percent level of significance (P < 0.05). Under the proposed optimized conditions, the model predicted a MTGase activity of 1.37 U.mL-1, very closely matching the experimental activity of 1.4 U.mL-1.


Asunto(s)
Streptomyces/enzimología , Transglutaminasas/química , Análisis de Varianza , Actinobacteria/aislamiento & purificación , Fraccionamiento Químico , Medios de Cultivo , Fermentación , Modelos Biológicos , Viscosidad
11.
J Biotechnol ; 122(3): 326-33, 2006 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-16446004

RESUMEN

An enzymatic approach, based on a transglutaminase-catalyzed coupling reaction, was investigated to modify bovine liver catalase with an end-group aminated dextran derivative. We demonstrated that catalase activity increased after enzymatic glycosidation and that the conjugate was 3.8-fold more stable to thermal inactivation at 55 degrees C and 2-fold more resistant to proteolytic degradation by trypsin. Moreover, the transglutaminase-mediated modification also improved the pharmacokinetics behavior of catalase, increasing 2.5-fold its plasma half-life time and reducing 3-fold the total clearance after its i.v. administration in rats.


Asunto(s)
Catalasa/química , Dextranos/química , Transglutaminasas/química , Animales , Cadaverina/análogos & derivados , Cadaverina/química , Catalasa/sangre , Catalasa/farmacocinética , Catálisis , Bovinos , Dextranos/farmacocinética , Diaminas/química , Femenino , Colorantes Fluorescentes/química , Ratas , Ratas Wistar , Streptomyces/enzimología
12.
Biotechnol Appl Biochem ; 37(Pt 3): 295-9, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12529180

RESUMEN

A new microbial transglutaminase (EC 2.3.2.13) from a Bacillus circulans strain isolated from the aquatic Amazonian environment was purified and characterized. Enzyme purification started with (NH(4))(2)SO(4) 'salting out' and proceeded with liquid chromatography on Q-Sepharose FF and octyl-Sepharose 4 FF. The purification factor was approx. 150-fold with a yield of 32%. The enzyme's molecular mass was estimated as 45000 Da on SDS/PAGE. The purified transglutaminase had an optimum temperature of 47 degrees C, the optimum pH of the reaction was 7 and it presented no calcium-dependent activity.


Asunto(s)
Bacillus/química , Reactores Biológicos , Cromatografía/métodos , Transglutaminasas/química , Transglutaminasas/aislamiento & purificación , Bacillus/enzimología , Brasil , Calcio/química , Activación Enzimática , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Cinética , Especificidad de la Especie , Temperatura , Teprotido , Transglutaminasas/antagonistas & inhibidores , Transglutaminasas/biosíntesis
13.
Biotechnol Bioeng ; 81(6): 732-7, 2003 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-12529888

RESUMEN

Bovine pancreatic trypsin was modified by the mono-6-amino-6-deoxy derivatives of alpha-, beta-, and gamma-cyclodextrin through a transglutaminase-catalyzed reaction. The trypsin-cyclodextrin conjugates, containing about 3 mol of oligosaccharide per mole of protein, were tested for their catalytic and stability properties. The specific esterolytic activity and the kinetics constants of trypsin were significantly improved following the transglutaminase-induced structural modifications. Trypsin-cyclodextrin conjugates were also found markedly (sixfold) more resistant to autolytic degradation at alkaline pH, and their thermal stability profile was improved by about 16 degrees C. Moreover, they were particularly resistant to heat inactivation when treated at different temperatures ranging from 45 degrees C to 70 degrees C for different periods of time.


Asunto(s)
Arginina/análogos & derivados , Arginina/química , Glucosiltransferasas/síntesis química , Complejos Multienzimáticos/síntesis química , Transglutaminasas/química , Tripsina/síntesis química , Animales , Catálisis , Bovinos , Coenzimas/síntesis química , Activación Enzimática , Estabilidad de Enzimas , Glucosiltransferasas/química , Calor , Cinética , Sustancias Macromoleculares , Complejos Multienzimáticos/química , Protones , Especificidad por Sustrato , Tripsina/química
14.
Biotechnol Lett ; 25(23): 2029-33, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14719818

RESUMEN

A Bacillus circulans strain, isolated in the Amazon basin, produced a transglutaminase (EC 2.3 x 2.13) in both submerged and solid-state cultivation. Enzyme activity in the former case reached 0.69 U ml(-1) after 160 h cultivation on starch based medium, and in the latter 0.61 U ml(-1) after 60 h cultivation on soybean industrial fibrous residue, a non-expensive agro-industrial residue.


Asunto(s)
Bacillus/crecimiento & desarrollo , Bacillus/metabolismo , Reactores Biológicos/microbiología , Técnicas de Cultivo de Célula/métodos , Glycine max/química , Transglutaminasas/biosíntesis , Transglutaminasas/química , Bacillus/clasificación , Activación Enzimática , Inmersión , Residuos Industriales/prevención & control , Eliminación de Residuos/métodos , Especificidad de la Especie
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