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1.
Biomacromolecules ; 25(3): 2024-2032, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38393758

RESUMEN

α-Glucan microparticles (GMPs) have significant potential as high-value biomaterials in various industries. This study proposes a bottom-up approach for producing GMPs using four amylosucrases from Bifidobacterium sp. (BASs). The physicochemical characteristics of these GMPs were analyzed, and the results showed that the properties of the GMPs varied depending on the type of enzymes used in their synthesis. As common properties, all GMPs exhibited typical B-type crystal patterns and poor colloidal dispersion stability. Interestingly, differences in the physicochemical properties of GMPs were generated depending on the synthesis rate of linear α-glucan by the enzymes and the degree of polymerization (DP) distribution. Consequently, we found differences in the properties of GMPs depending on the DP distribution of linear glucans prepared with four BASs. Furthermore, we suggest that precise control of the type and characteristics of the enzymes provides the possibility of producing GMPs with tailored physicochemical properties for various industrial applications.


Asunto(s)
Bifidobacterium , Glucanos , Guanosina Monofosfato , Tionucleótidos , Glucanos/química , Glucosiltransferasas
2.
J Korean Med Sci ; 38(25): e193, 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37365727

RESUMEN

BACKGROUND: Advances in neuroscience and neurotechnology provide great benefits to humans though unknown challenges may arise. We should address these challenges using new standards as well as existing ones. Novel standards should include ethical, legal, and social aspects which would be appropriate for advancing neuroscience and technology. Therefore, the Korea Neuroethics Guidelines were developed by stakeholders related to neuroscience and neurotechnology, including experts, policy makers, and the public in the Republic of Korea. METHOD: The guidelines were drafted by neuroethics experts, were disclosed at a public hearing, and were subsequently revised by opinions of various stakeholders. RESULTS: The guidelines are composed of twelve issues; humanity or human dignity, individual personality and identity, social justice, safety, sociocultural prejudice and public communication, misuse of technology, responsibility for the use of neuroscience and technology, specificity according to the purpose of using neurotechnology, autonomy, privacy and personal information, research, and enhancement. CONCLUSION: Although the guidelines may require a more detailed discussion after future advances in neuroscience and technology or changes in socio-cultural milieu, the development of the Korea Neuroethics Guidelines is a milestone for the scientific community and society in general for the ongoing development in neuroscience and neurotechnology.


Asunto(s)
Neurociencias , Privacidad , Humanos , Humanidades , República de Corea
3.
Appl Microbiol Biotechnol ; 106(12): 4563-4574, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35748913

RESUMEN

The effect of the Escherichia coli (E. coli) Rosetta (DE3) system on the expression of recombinant papain-like cysteine protease inhibitors (SnuCalCpIs) was evaluated, and the inhibition mode of the expressed inhibitor was determined. SnuCalCpI08 and SnuCalCpI17, which previously had not been expressed in the E. coli BL21 (DE3) system due to rare codons of more than 10%, were successfully expressed in E. coli Rosetta (DE3) since the strain provides tRNAs for six rare codons. Initially, both inhibitors were expressed as inclusion bodies; however, the water solubility of SnuCalCpI17 could be improved by lowering the incubation temperature, reducing the IPTG concentration, and increasing the induction time. In contrast, the other inhibitor could not be solubilized in water. To validate whether the inhibitor was expressed with correct protein folding, a papain inhibition assay was performed with SnuCalCpI17. SnuCalCpI17 showed a half-maximal inhibitory concentration (IC50) of 105.671 ± 9.857 µg/mL and a slow-binding inhibition mode against papain at pH 7.0 with a Kiapp of 75.80 µg/mL. The slow-binding inhibitor has a slow dissociation from the inhibitor-target complex, resulting in a long residence time in vivo, and thus can effectively inhibit the target at doses far below the IC50 of the inhibitor. KEY POINTS: • Propeptide inhibitor (SnuCalCpI17) containing rare codons was expressed in E. coli Rosetta (DE3). • The slow-binding inhibition was shown by plotting the apparent first-order rate constant (kobs). • Protein-protein interaction between SnuCalCpIs and papain was verified by docking simulation.


Asunto(s)
Escherichia coli , Papaína , Codón/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Papaína/genética , Papaína/metabolismo , Inhibidores de Proteasas , Proteínas Recombinantes/metabolismo , Agua/metabolismo
4.
Biomacromolecules ; 20(11): 4143-4149, 2019 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-31556605

RESUMEN

In this study, we created biocatalytically coated porous starch granules (PSGs) using amylosucrase from Neisseria polysaccharea to apply them as an encapsulant for target-specific delivery. Field-emission scanning electron and confocal laser scanning microscopic images showed that the PSGs were completely concealed by the α-glucan coating layer. This carbohydrate-based encapsulant displayed higher amount of resistant glucan contents due to the elongated chains of the glucan coating, resulting in lower digestibility of these PSGs in simulated digestive fluid systems. Among the various PSGs evaluated, the highest loading efficiency for the bioactive molecule crocin was observed with the ß-amylase-induced PSGs (ß-PSGs) that had the smallest nanosize pores. Furthermore, α-glucan-coated ß-PSGs showed the highest capacity to preserve the loaded crocin when incubated in simulated digestive fluids. This suggests that the α-glucan-coated ß-PSGs can potentially be used for the delayed release of the core material in the upper region of the gastrointestinal tract. Therefore, this system can be potentially utilized as an effective carrier for colon-specific delivery, and the release of the bioactive compound can be triggered by beneficial intestinal microbiota.


Asunto(s)
Portadores de Fármacos/farmacología , Glucanos/farmacología , Glucosiltransferasas/farmacología , Almidón/farmacología , Biocatálisis , Carotenoides/química , Carotenoides/farmacología , Colon/efectos de los fármacos , Colon/microbiología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Microbioma Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/microbiología , Glucanos/química , Glucosiltransferasas/química , Humanos , Microscopía Electrónica de Rastreo , Neisseria/enzimología , Especificidad de Órganos , Porosidad , Almidón/química
5.
Microb Cell Fact ; 18(1): 110, 2019 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-31196110

RESUMEN

BACKGROUND: Lactic acid bacteria (LAB) are known to have a significant ability to colonize the human intestinal tract and adhere to the surface of intestinal epithelial cells. Among the various lactic acid bacteria, exopolysaccharide (EPS) producing strains are known to provide a variety of health benefits for their hosts (e.g. anti-inflammatory, antioxidant, antitumor and stress tolerant effects). Recently, EPSs and EPS-producing lactic acid cultures have gained interest within the food industry and are playing important roles as biothickeners and texturizing agents due to their hydrocolloidal nature. In this study, 156 lactic acid bacterial strains isolated from fecal samples of healthy young children were screened and evaluated for active EPS-production capability. RESULTS: Among the various human origin lactic acid flora isolated, Weissella confusa VP30 showed the highest EPS productivity and its EPS producing properties were characterized under various cultural conditions in this research. To document the safety of W. confusa VP30, antibiotic resistance, hemolytic, and ammonia production properties were evaluated in addition. No significant negative results were observed. The maximum EPS production by W. confusa VP30 was 59.99 ± 0.91 g/l after 48 h of cultivation in media containing 10% sucrose, far exceeding EPS production by other bacterial strains reported elsewhere. Based on gel permeation chromatography (GPC), the molecular weight of EPS produced by W. confusa VP30 was 3.8 × 106 Da. Structural analysis of the released EPS fraction by 13C and 1H nuclear magnetic resonance (NMR) spectroscopy revealed that W. confusa VP30 can produce dextran with glucose units linked with 96.5% α (1 → 6) glycosidic bonds and 3.5% α (1 → 3) branches. CONCLUSION: The high EPS production capability and safety of W. confusa VP30 justify food industry consideration of this cell strain for further evaluation and potential industrial use.


Asunto(s)
Heces/microbiología , Polisacáridos Bacterianos/biosíntesis , Weissella/aislamiento & purificación , Preescolar , ADN Bacteriano/genética , Femenino , Humanos , Lactante , Espectroscopía de Resonancia Magnética , Masculino , Filogenia , Polisacáridos Bacterianos/química , ARN Ribosómico 16S/genética , Sacarosa/metabolismo , Weissella/clasificación , Weissella/genética , Weissella/metabolismo
6.
Eur Radiol ; 28(1): 390-397, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28677063

RESUMEN

OBJECTIVE: To determine the clinical efficacy of sonographically-guided percutaneous bone drilling of the lateral epicondyle (LE) for the treatment of patients with LE. METHODS: We included 24 patients with LE who reported pain in this study. All patients underwent sonographically-guided percutaneous bone drilling of the lateral epicondyle. Follow-up sonography and physical examinations were performed 1, 3 and 6 months after the procedure. The outcome measures included sonographic findings, visual analogue scale (VAS) score, maximum voluntary grip strength (MVGS) and patient-related tennis elbow evaluation (PRTEE) score. RESULTS: None of the patients had immediate complications during the procedure. The area of the extensor carpi radialis brevis (ECRB) tears decreased significantly at 1 month and declined gradually over the remaining 5 months of the study (p < 0.001). The mean pain VAS score was significantly lower at 6 months than preoperatively (respectively; p < 0.001). The mean MVGS increased significantly between pretreatment and 6 months post-treatment (p < 0.001), whereas the PRTEE score decreased significantly during the same period (p < 0.001). CONCLUSION: Sonographically-guided percutaneous drilling is a quick and safe treatment option for LE that can be performed in an outpatient setting. KEY POINTS: • Percutaneous drilling of the lateral condyle is effective for the treatment of LE. • The area of ECRB tears can be measured by US-guided saline injection. • US-guided percutaneous drilling is a quick and safe treatment option for LE.


Asunto(s)
Procedimientos Ortopédicos/métodos , Cirugía Asistida por Computador/métodos , Codo de Tenista/cirugía , Ultrasonografía/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Codo de Tenista/diagnóstico por imagen , Resultado del Tratamiento
7.
Molecules ; 23(3)2018 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-29558403

RESUMEN

Obesity is a public concern and is responsible for various metabolic diseases. Xylobiose (XB), an alternative sweetener, is a major component of xylo-oligosaccharide. The purpose of this study was to investigate the effects of XB on obesity and its associated metabolic changes in related organs. For these studies, mice received a 60% high-fat diet supplemented with 15% d-xylose, 10% XB, or 15% XB as part of the total sucrose content of the diet for ten weeks. Body weight, fat and liver weights, fasting blood glucose, and blood lipids levels were significantly reduced with XB supplementation. Levels of leptin and adipokine were also improved and lipogenic and adipogenic genes in mesenteric fat and liver were down-regulated with XB supplementation. Furthermore, pro-inflammatory cytokines, fatty acid uptake, lipolysis, and ß-oxidation-related gene expression levels in mesenteric fat were down-regulated with XB supplementation. Thus, XB exhibited therapeutic potential for treating obesity which involved suppression of fat deposition and obesity-related metabolic disorders.


Asunto(s)
Tejido Adiposo/metabolismo , Adiposidad/efectos de los fármacos , Disacáridos/farmacología , Disacáridos/uso terapéutico , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Adipogénesis/efectos de los fármacos , Adipogénesis/genética , Tejido Adiposo/efectos de los fármacos , Animales , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Citocinas/metabolismo , Dieta Alta en Grasa , Ácidos Grasos/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Lípidos/sangre , Lipogénesis/efectos de los fármacos , Lipogénesis/genética , Lipólisis/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Ratones Endogámicos C57BL , Obesidad/genética , Obesidad/prevención & control , Tamaño de los Órganos/efectos de los fármacos , Oxidación-Reducción
8.
Phytochem Anal ; 27(2): 140-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26895991

RESUMEN

INTRODUCTION: Hydrangea leaf tea has been traditionally consumed in the far-east Asian countries and is favoured for its distinct minty-sweet taste. Phyllodulcin is identified as a key sweet-tasting compound; it is 400-800 times sweeter than sucrose. However, its extraction has not been well-documented. In an effort to optimise phyllodulcin production, pretreatment processes to accumulate phyllodulcin as a final metabolite in leaf tissue were studied, and an efficient process was established for the extraction and purification of phyllodulcin. METHODS: Phyllodulcin was structurally identified using an LC/MS system. Hydrangea leaves were processed by either hand rolling or mechanical blending, by exposing them at different drying temperatures (25 and 70°C), and even by inducing bioconversion in leaf tissue. The leaf powder was extracted with various solvents (methanol, ethanol, and water) by soaking at 25°C for 12 h, ultrasonication at 35°C for 1 h or accelerated solvent extraction (ASE). Extracts were purified with ion exchange resins and purified using preparative HPLC. RESULTS: Traditional hand rolling and drying at 70°C significantly increased phyllodulcin accumulation in the leaves. Meanwhile, more phyllodulcin was obtained from the leaves blended mechanically or converted enzymatically compared to traditionally processed ones (P < 0.05). Methanol and ethanol were superior to water as extraction media, and the greatest phyllodulcin yields obtained by ASE, soaking and ultrasonication were 21.28, 21.20 and 19.33 mg/g, respectively, when methanol was used. Highly pure phyllodulcin powder was obtained with a yield of 2.12%. CONCLUSIONS: This promising result would be beneficial to the industrial utilisation of phyllodulcin as a potential high-intensity sweetener.


Asunto(s)
Hydrangea/metabolismo , Isocumarinas/metabolismo , Hojas de la Planta/metabolismo , Cromatografía Líquida de Alta Presión , Isocumarinas/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta
9.
J Sci Food Agric ; 96(3): 1037-43, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25827339

RESUMEN

BACKGROUND: The potential of the protein-polyphenol interaction was applied to crosslinking reinforced protein networks in gluten-free rice noodles. Specifically, inter-component interaction between soy protein isolate and extract of Acanthopanax sessiliflorus fruit (ogaja) was examined with a view to improving its quality. RESULTS: In a components-interacting model system, a mixture of soy protein isolate (SPI) and ogaja extract (OE) induced a drastic increase in absorbance at 660 nm by haze formation, while the major anthocyanin of ogaja, cyanidin-3-O-sambubioside, sparsely interacted with SPI or gelatin. Individual or combined treatment of SPI and OE on rice dough decreased all the viscosity parameters in rapid visco analysis. However, SPI-OE treatment significantly increased all the texture parameters of rice dough derived from Mixolab(®) analysis (P < 0.05). Incorporation of SPI in rice dough significantly reduced endothermic ΔH, and SPI-OE treatment further decreased this value. SPI-OE interaction significantly increased the tensile properties of cooked noodle and decreased 53.7% of cooking loss compared to the untreated rice noodle. CONCLUSION: SPI-OE treatment caused a considerable reinforcement of the network as shown by reducing cooking loss and suggested the potential for utilizing protein-polyphenol interaction for gluten-free rice noodle production.


Asunto(s)
Eleutherococcus , Calidad de los Alimentos , Extractos Vegetales , Culinaria , Dieta Sin Gluten , Humanos , Polifenoles/química , Proteínas de Soja/química
10.
Int J Biol Macromol ; 273(Pt 2): 133205, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38885871

RESUMEN

Although myricetin (3,3',4',5,5',7-hexahydroxyflavone, MYR) has a high antioxidant capacity and health functions, its use as a functional food material is limited owing to its low stability and water solubility. Amylosucrase (ASase) is capable of biosynthesizing flavonol α-glycoside using flavonols as acceptor molecules and sucrose as a donor molecule. Here, ASase from Deinococcus deserti (DdAS) efficiently biosynthesizes a novel MYR α-triglucoside (MYRαG3) using MYR as the acceptor molecule. Comparative homology analysis and computational simulation revealed that DdAS has a different active pocket for the transglycosylation reaction. DdAS produced MYRαG3 with a conversion efficiency of 67.4 % using 10 mM MYR and 50 mM sucrose as acceptor and donor molecules, respectively. The structure of MYRαG3 was identified as MYR 4'-O-4″,6″-tri-O-α-D-glucopyranoside using NMR and LC-MS. In silico analysis confirmed that DdAS has a distinct active pocket compared to other ASases. In addition, molecular docking simulations predicted the synthetic sequence of MYRαG3. Furthermore, MYRαG3 showed a similar DPPH radical scavenging activity of 49 %, comparable to MYR, but with significantly higher water solubility, which increased from 0.03 µg/mL to 511.5 mg/mL. In conclusion, this study demonstrated the efficient biosynthesis of a novel MYRαG3 using DdAS and highlighted the potential of MYRαG3 as a functional material.


Asunto(s)
Deinococcus , Flavonoides , Glucósidos , Glucosiltransferasas , Solubilidad , Deinococcus/enzimología , Glucosiltransferasas/química , Glucosiltransferasas/metabolismo , Flavonoides/química , Flavonoides/metabolismo , Flavonoides/biosíntesis , Glucósidos/química , Glucósidos/biosíntesis , Glucósidos/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Simulación del Acoplamiento Molecular
11.
Int J Biol Macromol ; 265(Pt 1): 130667, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38453106

RESUMEN

Glycogen is a naturally occurring or metabolically synthesized biological macromolecule found in a wide range of living organisms, including animals, microorganisms, and even plants. However, naturally sourced glycogen poses challenges for industrial use. This study focused on a biological macromolecule referred to as glycogen-like particles (GLPs), detailing the production methods and biological properties of these particles. In vitro enzymatic production of GLPs was successfully achieved. GLPs synthesized through a simultaneous enzymatic reaction using sucrose had significant changes in their structure and functionality based on the branching enzyme (BE) to amylosucrase (ASase) ratio. As this ratio increased, the GLPs developed higher molecular weights and greater density, solubility, and branching degree while reducing size and turbidity. Structural changes in these enzymes were not observed beyond a critical BE/ASase ratio. Uniformly dispersed curcumin powder was generated in 50 % (w/v) aqueous GLP solution, and the GLPs were non-toxic to human skin keratinocytes at a concentration of 2.5 mg/mL. GLPs with lower branching inhibited tyrosinase activity and melanin synthesis, while those with more long chains displayed effective UV-blocking. By manipulating the BE/ASase ratio, GLPs were shown to display diverse chemical structures and physical characteristics, suggesting their potential application in the food and cosmetics industries.


Asunto(s)
Enzima Ramificadora de 1,4-alfa-Glucano , Cosméticos , Humanos , Glucógeno/química , Piel
12.
Carbohydr Polym ; 335: 122087, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38616077

RESUMEN

The aim of this study was to evaluate the impacts of enzymatically synthesized α-glucans possessing α-1,4- and α-1,6-glucose linkages, and varying in branching ratio, on colonic microbiota composition and metabolic function. Four different α-glucans varying in branching ratio were synthesized by amylosucrase from Neisseria polysaccharea and glycogen branching enzyme from Rhodothermus obamensis. The branching ratios were found to range from 0 % to 2.8 % using GC/MS. In vitro fecal fermentation analyses (n = 8) revealed that the branching ratio dictates the short-chain fatty acid (SCFA) generation by fecal microbiota. Specifically, slightly branched (0.49 %) α-glucan resulted in generation of significantly (P < 0.05) higher amounts of propionate, compared to more-branched counterparts. In addition, the amount of butyrate generated from this α-glucan was statistically (P > 0.05) indistinguishable than those observed in resistant starches. 16S rRNA sequencing revealed that enzymatically synthesized α-glucans stimulated Lachnospiraceae and Ruminococcus related OTUs. Overall, the results demonstrated metabolic function of colonic microbiota can be manipulated by altering the branching ratio of enzymatically synthesized α-glucans, providing insights into specific structure-function relationships between dietary fibers and the colonic microbiome. Furthermore, the slightly branched α-glucans could be used as functional carbohydrates to stimulate the beneficial microbiota and SCFAs in the colon.


Asunto(s)
Enzima Ramificadora de 1,4-alfa-Glucano , Microbiota , Fermentación , ARN Ribosómico 16S/genética , Glucanos
13.
Int J Biol Macromol ; 269(Pt 2): 131834, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38688341

RESUMEN

The amylosucrase (ASase, EC 2.4.1.4) utilizes sucrose as the sole substrate to catalyze multifunctional reactions. It can naturally synthesize α-1,4-linked glucans such as amylose as well as sucrose isomers with more favorable properties than sucrose with a lower intestinal digestibility and non-cariogenic properties. The amino acid sequence of the asase gene from Deinococcus cellulosilyticus (DceAS) exhibits low homology with those of other ASases from other Deinococcus species. In this study, we cloned and expressed DceAS and demonstrated its high activity at pH 6 and pH 8 and maintained stability. It showed higher polymerization activity at pH 6 than at pH 8, but similar isomerization activity and produced more turanose and trehalulose at pH 6 than at pH 8 and produced more isomaltulose at pH 8. Furthermore, the molecular weight of DceAS was 226.6 kDa at pH 6 and 145.5 kDa at pH 8, indicating that it existed as a trimer and dimer, respectively under those conditions. Additionally, circular dichroism spectra showed that the DceAS secondary structure was different at pH 6 and pH 8. These differences in reaction products at different pHs can be harnessed to naturally produce sucrose alternatives that are more beneficial to human health.


Asunto(s)
Deinococcus , Glucosiltransferasas , Glucosiltransferasas/química , Glucosiltransferasas/genética , Glucosiltransferasas/metabolismo , Deinococcus/enzimología , Deinococcus/genética , Concentración de Iones de Hidrógeno , Isomaltosa/metabolismo , Isomaltosa/química , Isomaltosa/análogos & derivados , Secuencia de Aminoácidos , Estabilidad de Enzimas , Clonación Molecular , Peso Molecular , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sacarosa/metabolismo , Especificidad por Sustrato , Cinética , Estructura Secundaria de Proteína , Disacáridos
14.
Food Chem ; 448: 139182, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38569413

RESUMEN

Amylosucrase (ASase) efficiently biosynthesizes α-glucoside using flavonoids as acceptor molecules and sucrose as a donor molecule. Here, ASase from Deinococcus wulumuqiensis (DwAS) biosynthesized more naringenin α-glucoside (NαG) with sucrose and naringenin as donor and acceptor molecules, respectively, than other ASases from Deinococcus sp. The biotransformation rate of DwAS to NαG was 21.3% compared to 7.1-16.2% for other ASases. Docking simulations showed that the active site of DwAS was more accessible to naringenin than those of others. The 217th valine in DwAS corresponded to the 221st isoleucine in Deinococcus geothermalis AS (DgAS), and the isoleucine possibly prevented naringenin from accessing the active site. The DwAS-V217I mutant had a significantly lower biosynthetic rate of NαG than DwAS. The kcat/Km value of DwAS with naringenin as the donor was significantly higher than that of DgAS and DwAS-V217I. In addition, NαG inhibited human intestinal α-glucosidase more efficiently than naringenin.


Asunto(s)
Proteínas Bacterianas , Biotransformación , Deinococcus , Flavanonas , Glucósidos , Glucosiltransferasas , Inhibidores de Glicósido Hidrolasas , Flavanonas/metabolismo , Flavanonas/química , Deinococcus/enzimología , Deinococcus/metabolismo , Deinococcus/química , Deinococcus/genética , Glucosiltransferasas/metabolismo , Glucosiltransferasas/química , Glucosiltransferasas/genética , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/metabolismo , Inhibidores de Glicósido Hidrolasas/farmacología , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Glucósidos/metabolismo , Glucósidos/química , Simulación del Acoplamiento Molecular , Cinética , alfa-Glucosidasas/metabolismo , alfa-Glucosidasas/química
15.
Planta Med ; 79(17): 1636-40, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24214832

RESUMEN

Anthocyanins play an important role in physiological functions related to human health. This study aimed to investigate the inhibitory effect of cyanidin-3-O-sambubioside isolated from Acanthopanax sessiliflorus fruit on cancer cell metastasis. The inhibitory effect of cyanidin-3-O-sambubioside on angiogenesis was assessed by chorioallantoic membrane and tube formation assays. Cyanidin-3-O-sambubioside interrupted the formation of neovasculature and tube-like structures in a dose-dependent manner. It inhibited the wound healing migration and invasion of MDA-MB-231 cells through reconstituted extracellular matrix (Matrigel). Gelatin zymography revealed that cyanidin-3-O-sambubioside significantly decreased the secretion of matrix metalloproteinase-9 and inhibited matrix metalloproteinase-9 expression. In additional, cyanidin-3-O-sambubioside exerted an inhibitory effect on Akt phosphorylation. These results suggest that cyanidin-3-O-sambubioside inhibits metastasis processes, such as angiogenesis and invasion, in breast cancer cells through regulation of matrix metalloproteinase-9 activity.


Asunto(s)
Antocianinas/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Movimiento Celular/efectos de los fármacos , Eleutherococcus/química , Metaloproteinasa 9 de la Matriz/metabolismo , Fitoterapia , Extractos Vegetales/uso terapéutico , Inhibidores de la Angiogénesis/farmacología , Inhibidores de la Angiogénesis/uso terapéutico , Animales , Antocianinas/farmacología , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Embrión de Pollo , Membrana Corioalantoides , Disacáridos , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Matriz Extracelular , Femenino , Frutas/química , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , FN-kappa B/metabolismo , Neovascularización Patológica , Fosforilación , Extractos Vegetales/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo
16.
Carbohydr Polym ; 310: 120730, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36925263

RESUMEN

α-Limit dextrins (α-LDx) are slowly digestible carbohydrates that attenuate postprandial glycemic response and trigger the secretion of satiety-related hormones. In this study, more highly branched α-LDx were enzymatically synthesized to enhance the slowly digestible property by various origins of glycogen branching enzyme (GBE), which catalyzes the transglycosylation to form α-1,6 branching points after cleaving α-1,4 linkages. Results showed that the proportion of branched α-LDx in starch molecules increased around 2.2-8.1 % compared to α-LDx from starch without GBE treatment as the ratio of α-1,6 linkages increased after different types of GBE treatments. Furthermore, the enzymatic increment of branching points enhanced the slowly digestible properties of α-LDx at the mammalian α-glucosidase level by 17.3-28.5 %, although the rates of glucose generation were different depending on the source of GBE treatment. Thus, the highly branched α-LDx with a higher amount of α-1,6 linkages and a higher molecular weight can be applied as a functional ingredient to deliver glucose throughout the entire small intestine without a glycemic spike which has the potential to control metabolic diseases such as obesity and type 2 diabetes.


Asunto(s)
Enzima Ramificadora de 1,4-alfa-Glucano , Diabetes Mellitus Tipo 2 , Animales , Humanos , Dextrinas , Enzima Ramificadora de 1,4-alfa-Glucano/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Almidón/metabolismo , Glucosa , Glucógeno , Mamíferos/metabolismo
17.
Int J Biol Macromol ; 242(Pt 2): 124921, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37201882

RESUMEN

Amylosucrase from Neisseria polysaccharea (NpAS) produces the linear amylose-like α-glucans by the elongation property from sucrose, and 4,3-α-glucanotransferase from Lactobacillus fermentum NCC 2970 (4,3-αGT) newly synthesizes the α-1,3 linkages after cleaving the α-1,4 linkages by the glycosyltransferring property. This study focused on the synthesis of high molecular α-1,3/α-1,4-linked glucans by combining NpAS and 4,3-αGT and analyzed their structural and digestive properties. The enzymatically synthesized α-glucans have a molecular weight of >1.6 × 107 g mol-1, and the α-4,3 branching ratios on the structures increased as the amount of 4,3-αGT increased. The synthesized α-glucans were hydrolyzed to linear maltooligosaccharides and α-4,3 branched α-limit dextrins (α-LDx) by human pancreatic α-amylase, and the amounts of produced α-LDx were increased depending on the ratio of synthesized α-1,3 linkages. In addition, approximately 80 % of the synthesized products were partially hydrolyzed by mammalian α-glucosidases, and the glucose generation rates decelerated as the amounts of α-1,3 linkages increased. In conclusion, new types of α-glucans with α-1,4 and α-1,3 linkages were successfully synthesized by a dual enzyme reaction. These can be utilized as slowly digestible and prebiotic ingredients in the gastrointestinal tract due to their novel linkage patterns and high molecular weights.


Asunto(s)
Glucanos , Glicosiltransferasas , Animales , Humanos , Glucanos/química , Glucosa/química , alfa-Glucosidasas , Sacarosa/química , Mamíferos
18.
Food Sci Biotechnol ; 32(9): 1299, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37362806

RESUMEN

[This corrects the article DOI: 10.1007/s10068-019-00686-6.].

19.
Carbohydr Polym ; 309: 120646, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36906355

RESUMEN

Glycogen-like particles (GLPs) are applied in food, pharmaceutical, and cosmetics. The large-scale production of GLPs is limited by their complicated multi-step enzymic processes. In this study, GLPs were produced in a one-pot dual-enzyme system using Bifidobacterium thermophilum branching enzyme (BtBE) and Neisseria polysaccharea amylosucrase (NpAS). BtBE showed excellent thermal stability (half-life of 1732.9 h at 50 °C). Substrate concentration was the most influential factor during GLPs production in this system: GLPs yield and [sucrose]ini decreased from 42.4 % to 17.4 % and 0.3 to 1.0 M, respectively. Molecular weight and apparent density of GLPs decreased significantly with increasing [sucrose]ini. Regardless of the [sucrose]ini, the DP 6 of branch chain length was predominantly occupied. GLP digestibility increased with increasing [sucrose]ini, indicating that the degree of GLP hydrolysis may be negatively related to its apparent density. This one-pot biosynthesis of GLPs using a dual-enzyme system could be useful for the development of industrial processes.


Asunto(s)
Enzima Ramificadora de 1,4-alfa-Glucano , Glucanos , Sacarosa/química , Glucosiltransferasas/química , Bifidobacterium , Neisseria
20.
Foods ; 12(5)2023 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-36900622

RESUMEN

Patients with galactosemia accumulate galactose in their bodies, requiring a lifelong galactose-restricted diet. Therefore, accurate information on the galactose content in commercial agro-food resources is essential. The HPLC method generally used for sugar analysis has low separation and detection sensitivity. Here, we sought to establish an accurate analytical method for determining the galactose content in commercial agro-food resources. To that aim, we employed gas chromatography with flame-ionization detection to detect trimethylsilyl-oxime (TMSO) sugar derivatives (concentration: ≤0.1 mg/100 g). The galactose content in 107 Korean agro-food resources reflecting intake patterns was then analyzed. The galactose content in steamed barley rice was 5.6 mg/100 g, which was higher than that in steamed non-glutinous and glutinous rice. Moist-type and dry-type sweet potatoes, blanched zucchini, and steamed Kabocha squash had high galactose content (36.0, 12.8, 23.1, and 61.6 mg/100 g, respectively). Therefore, these foods are detrimental to patients with galactosemia. Among fruits, avocado, blueberry, kiwi, golden kiwifruit, and sweet persimmon had galactose contents of ≥10 mg/100 g. Dried persimmon had 132.1 mg/100 g and should therefore be avoided. Mushrooms, meat, and aquatic products showed low galactose content (≤10 mg/100 g), making them safe. These findings will help patients to manage their dietary galactose intake.

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