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1.
Food Chem ; 322: 126767, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32330787

RESUMO

Due to the lack of innovative valorization strategies, berry pomaces are a poorly utilized as a cheap source of valuable nutrients and phytochemicals. An effective biorefining scheme was developed to recover functional components from lingonberry pomace by consecutive supercritical CO2 (SFE-CO2), pressurized liquid (PLE) and enzyme assisted (EAE) extractions. SFE-CO2 at optimized parameters yielded 11.8 g/100 g of lipophilic fraction, containing 43.3 and 37.4% of α-linolenic and linoleic fatty acids, respectively. The combined PLE with ethanol and water additionally recovered 61.8 g/100 g of polar constituents and reduced the antioxidant capacity of starting material by up to 94%. The major portion of the antioxidants (89-94% in different assays), anthocyanins (231 mg/100 g pomace) and proanthocyanidins (15.9 g/100 g pomace) was present in PLE-EtOH extract. Cyanidin-3-galactoside was the major anthocyanin (146.9 mg/100 g). High-pressure fractionation was more efficient for obtaining bioactive pomace constituents as compared with conventional and enzyme-assisted extractions.


Assuntos
Fracionamento Químico/métodos , Solventes/química , Vaccinium vitis-Idaea , Gerenciamento de Resíduos/métodos , Antocianinas/análise , Antocianinas/química , Antioxidantes/análise , Antioxidantes/química , Dióxido de Carbono/química , Etanol/química , Frutas/química , Galactosídeos/análise , Galactosídeos/química , Química Verde , Resíduos Industriais , Complexos Multienzimáticos/química , Complexos Multienzimáticos/metabolismo , Pressão , Proantocianidinas/análise , Proantocianidinas/química , Água
2.
Food Chem ; 318: 126549, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32151920

RESUMO

Cornelian cherry (CC) fruits a source of bioactive compounds that are still being underutilized. In this study, a comprehensive characterization of 11 Montenegrin CC local or introduced genotypes and cultivars collected in the wild or from organic orchards is provided. Their potential utilizations as natural antioxidants, colorants and organic food ingredients were exploited. CC fruits had high level of vitamin C (48-108 mg/100 g), malic acid (104-375 mg/100 g), and total polyphenols (158-591mgGAE/100 g). They also displayed high antioxidant activity based on DPPH (623-1903µmolTE/100 g), ABTS (441-1475µmolTE/100 g), and FRAP (1509-5954µmolFe2+/100 g) assays. UHPLC-PDA-HESI-MS/MS analyses were used to quantify the concentration of phenolic acids (7.69-19.87 mg/100 g), flavonoids (10.87-44.34 mg/100 g), anthocyanins (11.85-195.43 mg/100 g) and iridoids (129.07-341.20 mg/100 g). For each of this groups, the most abundant were caftaric acid (12.24 mg/100 g), quercetin 3-glucuronide (29.66 mg/100 g), cyanidin 3-O-galactoside (130.93 mg/100 g) and loganic acid (303.3 mg/100 g), respectively. PCA and cluster heatmap analysis highlighted potentials for further exploitation of local genotypes and cultivars through organic food processing and breeding program.


Assuntos
Cornus/química , Cornus/genética , Antocianinas/análise , Antioxidantes/análise , Ácido Ascórbico/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Análise de Alimentos/métodos , Frutas/química , Galactosídeos/análise , Iridoides/análise , Montenegro , Fenóis/análise , Polifenóis/análise , Espectrometria de Massas em Tandem
3.
Food Chem ; 312: 126124, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31926461

RESUMO

Apple is rich in flavonol glycosides, which are believed to contribute to putative health benefits associated with apple consumption. Glycosylation, catalyzed by uridine diphospho-glycosyltransferases (UGTs), is the last step in flavonol biosynthesis, which confers molecular stability and solubility to the flavonol. In the present study, the involvement of two UGTs, MdUGT75B1 and MdUGT71B1, in flavonol biosynthesis in apple was investigated. The major flavonols are quercetin 3-O-glycosides, and UV-B and blue light treatment significantly enhanced the accumulation of quercetin 3-O-galactoside, quercetin 3-O-glucoside, and kaempferol 3-O-galactoside. Transcript levels of MdUGT75B1 and MdUGT71B1 in fruit subjected to different treatments were correlated well with flavonol accumulation. MdUGT75B1 showed flavonol-specific activity with a preference for UDP-galactose as the sugar donor, while MdUGT71B1 using UDP-glucose exhibited a wider substrate acceptance. Thus, MdUGT75B1 and MdUGT71B1 are key UGTs involved in flavonol biosynthesis and may have important roles in regulating accumulation of these health-promoting bioactive compounds in apple.


Assuntos
Galactosídeos/biossíntese , Glucosídeos/biossíntese , Glicosiltransferases/metabolismo , Quempferóis/biossíntese , Malus/química , Quercetina/análogos & derivados , Frutas/química , Frutas/metabolismo , Malus/metabolismo , Quercetina/biossíntese , Uridina/metabolismo
4.
Proc Natl Acad Sci U S A ; 117(2): 977-981, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31889006

RESUMO

LacY catalyzes accumulation of galactosides against a concentration gradient by coupling galactoside and H+ transport (i.e., symport). While alternating access of sugar- and H+-binding sites to either side of the membrane is driven by binding and dissociation of sugar, the electrochemical H+ gradient ([Formula: see text]) functions kinetically by decreasing the Km for influx 50- to 100-fold with no change in Kd The affinity of protonated LacY for sugar has an apparent pK (pKapp) of ∼10.5, due specifically to the pKa of Glu325, a residue that plays an irreplaceable role in coupling. In this study, rates of lactose/H+ efflux were measured from pH 5.0 to 9.0 in the absence or presence of a membrane potential (ΔΨ, interior positive), and the effect of the imposed ΔΨ on the kinetics of efflux was also studied in right-side-out membrane vesicles. The findings reveal that [Formula: see text] induces an asymmetry in the transport cycle based on the following observations: 1) the efflux rate of WT LacY exhibits a pKapp of ∼7.2 that is unaffected by the imposed ΔΨ; 2) ΔΨ increases the rate of efflux at all tested pH values, but enhancement is almost 2 orders of magnitude less than observed for influx; 3) mutant Glu325 - Ala does little or no efflux in the absence or presence of ΔΨ, and ambient pH has no effect; and 4) the effect of ΔΨ (interior positive) on the Km for efflux is almost insignificant relative to the 50- to 100-fold decrease in the Km for influx driven by ΔΨ (interior negative).


Assuntos
Galactosídeos/metabolismo , Potenciais da Membrana/fisiologia , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/metabolismo , Prótons , Sítios de Ligação , Transporte Biológico , Concentração de Íons de Hidrogênio , Transporte de Íons , Cinética , Lactose/metabolismo , Proteínas de Membrana Transportadoras/genética , Modelos Moleculares
5.
Food Chem ; 315: 126175, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31991254

RESUMO

The food industry is increasingly innovating and applying new processing technologies and ingredients to develop novel food products that meet the consumers' demand. In this study, the effect of extrusion (at 140 °C and 160 °C) was evaluated in different lentil flours formulations enriched with nutritional yeast, in terms of α-galactosides (raffinose, stachyose, verbascose), inositol phosphates (IPs), trypsin inhibitors and lectins content. The content of α-galactosides and IPs was determined by high performance liquid chromatography. Trypsin inhibitor activity (TIA) was evaluated using a small-scale quantitative assay. The lectin content was analyzed using a haemagglutination assay and a Competitive Indirect Enzyme-linked immunosorbent assay. Extrusion promoted a significant increase, up to 85% in total α-galactosides content. After extrusion, IPs content was significantly decreased and TIA as well as lectins content had a reduction higher than 90%. Extrusion demonstrated to have a beneficial effect by increasing desirable prebiotic compounds and decreasing non-nutritional factors.


Assuntos
Farinha/análise , Alimentos Formulados/análise , Lens (Planta)/química , Compostos Fitoquímicos/química , Fermento Seco/química , Animais , Cromatografia Líquida de Alta Pressão , Dieta Livre de Glúten , Análise de Alimentos/métodos , Indústria de Processamento de Alimentos/métodos , Galactosídeos/análise , Testes de Hemaglutinação , Fosfatos de Inositol/análise , Oligossacarídeos/análise , Compostos Fitoquímicos/análise , Ratos , Inibidores da Tripsina/análise
6.
Biosci Biotechnol Biochem ; 84(4): 797-799, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31790630

RESUMO

Insect gall structures have many characteristic forms and colors, which are distinguishable from host plants. In this study, we identified an anthocyanin from red color insect galls and revealed that the anthocyanin biosynthesis of plants was induced by the gall extracts. The galling insects presumably regulate the anthocyanin biosynthesis of host plants to protect their larvae from environmental stresses.


Assuntos
Antocianinas/química , Ceratopogonidae/fisiologia , Fagus/parasitologia , Galactosídeos/química , Interações Hospedeiro-Parasita , Animais , Antocianinas/biossíntese , Ceratopogonidae/crescimento & desenvolvimento , Fagus/metabolismo , Larva/fisiologia
7.
Xenobiotica ; 50(4): 454-457, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31269857

RESUMO

1. Anthocyanins are a subgroup of flavonoids responsible for the blue, purple and red color of many fruits, flowers and leaves. Consumption of foods rich in anthocyanins is associated with a reduced risk of cardiovascular disease and cancer. Most food intervention studies employ once or twice per day dose schedules. 2. The current study demonstrated that plasma concentrations of cyanidin-3-galactoside and cyanidin-3-xyloside, the two major components of saskatoon berries, were significantly increased following three consecutive saskatoon berry supplements 4 hours apart. This accumulation is due to the residual concentrations of anthocyanins at the time of second and third supplements. 3. Accumulation was especially pronounced for peonidin-3-glucoside and peonidin-3-galactoside, the methylated metabolites of cyanidin-3-glucoside and cyanidin-3-galactoside, respectively. Little or no accumulation was observed for cyanidin-3-arabinoside and cyanidin-3-glucoside, two other components of saskatoon berries, possibly due to their short half-lives. 4. Thus, taking anthocyanin supplements with every meal would provide higher plasma concentrations for some anthocyanins and their metabolites than the once or twice-a-day dose regimens.


Assuntos
Antocianinas/sangue , Suplementos Nutricionais , Rosaceae , Galactosídeos , Glucosídeos , Humanos , Plasma/metabolismo
8.
Chem Asian J ; 14(24): 4837-4846, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31756283

RESUMO

Three-dimensional (3D) scaffolds formed from natural biopolymers gelatin and chitosan that are chemically modified by galactose have shown improved hepatocyte adhesion, spheroid geometry and functions of the hepatocytes. Galactose specifically binds to the hepatocytes via the asialoglycoprotein receptor (ASGPR) and an increase in galactose density further improves the hepatocyte proliferation and functions. In this work, we aimed to increase the galactose density within the biopolymeric scaffold by physically blending the biopolymers chitosan and gelatin with an amphiphlic ß-galactose polypeptide (PPO-GP). PPO-GP, is a di-block copolymer with PPO and ß-galactose polypeptide, exhibits lower critical solution temperature and is entrapped within the scaffold through hydrophobic interactions. The uniform distribution of PPO-GP within the scaffold was confirmed by fluorescence microscopy. SEM and mechanical testing of the hybrid scaffolds indicated pore size, inter connectivity and compression modulus similar to the scaffolds made from 100 % biopolymer. The presence of the PPO-GP on the surface of the scaffold was tested monitoring the interaction of an analogous mannose containing PPO-GP scaffold and the mannose binding lectin Con-A. In vitro cell culture experiments with HepG2 cells were performed on GLN-GP and CTS-GP and their cellular response was compared with GLN and CTS scaffolds for a period of seven days. Within three days of culture the Hep G2 cells formed multicellular spheroids on GLN-GP and CTS-GP more efficiently than on the GLN and CTS scaffolds. The multicellular spheroids were also found to infiltrate more in GLN-GP and CTS-GP scaffolds and able to maintain their round morphology as observed by live/dead and SEM imaging.


Assuntos
Quitosana/química , Gelatina/química , Glicoproteínas/química , Hepatócitos/metabolismo , Polímeros/química , Propilenoglicóis/química , Tecidos Suporte/química , Animais , Módulo de Elasticidade , Galactosídeos/química , Células Hep G2 , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Esferoides Celulares/metabolismo , Suínos , Engenharia Tecidual/métodos
9.
Carbohydr Res ; 486: 107821, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31580966

RESUMO

Molecular recognition of saccharides is a growing field, which has many implications in cancer therapy, drug discovery, and cellular communication among others. The participation of CH/π interactions in this event is well known. Nevertheless, the intrinsic role of CH/π for modulating chemical reactions is still far from being applicable. In this experimental and computational work we have evaluated the participation of CH/π interactions in the aminolysis reaction of acetyl galactoside promoted with different 6-substituted 2(1H)-pyridones. Two features have been incorporated to the promoter molecular structure, on one end the promoting pyridone group and on the other end the recognition moiety, joined together by an alkyne spacer. The small increment in the observed pseudo-first-order rate constant values (kobs) was related to the stability of the transition state provided by noncovalent interactions, including CH/π interactions. A longer alkyne spacer was necessary to improve the molecular recognition of the galactoside substrate. The trend of the calculated activation energy values (ΔERTS) was in good accordance with the experimental rate constant values.


Assuntos
Galactosídeos/química , Teoria Quântica , Aminas/química , Configuração de Carboidratos , Ligação de Hidrogênio , Modelos Moleculares
10.
Chem Commun (Camb) ; 55(81): 12204-12207, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31549691

RESUMO

Perfluorophenylboronic acid 1c catalyzes the direct stereoselective addition of alcohol nucleophiles to deactivated peracetylated d-galactal to give 2-deoxygalactosides in 55-88% yield with complete α-selectivity. The unprecedented results reported here also enable the synthesis of disaccharides containing the 2-deoxygalactose moiety directly from the deactivated peracetylated d-galactal. This convenient and metal-free glycosylation method works well with a wide range of alcohol nucleophiles as acceptors and tolerates a range of functional groups without the formation of the Ferrier byproduct and without the need for a large excess of nucleophiles or additives. The method is potentially useful for the synthesis of a variety of α-2-deoxygalactosides.


Assuntos
Ácidos Borônicos/química , Galactose/análogos & derivados , Galactosídeos/síntese química , Acetilação , Catálise , Dissacarídeos/química , Galactose/química , Glicosilação , Estrutura Molecular , Solventes/química , Estereoisomerismo , Temperatura
11.
Molecules ; 24(15)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366105

RESUMO

The biological process, 3-O-galactosylation, is important in plant cells. To understand the mechanism of the reduction of flavonol antioxidative activity by 3-O-galactosylation, myricetin-3-O-galactoside (M3OGa) and myricetin aglycone were each incubated with 2 mol α,α-diphenyl-ß-picrylhydrazyl radical (DPPH•) and subsequently comparatively analyzed for radical adduct formation (RAF) products using ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-Q-TOF-MS) technology. The analyses revealed that M3OGa afforded an M3OGa-DPPH adduct (m/z 873.1573) and an M3OGa-M3OGa dimer (m/z 958.1620). Similarly, myricetin yielded a myricetin-DPPH adduct (m/z 711.1039) and a myricetin-myricetin dimer (m/z 634.0544). Subsequently, M3OGa and myricetin were compared using three redox-dependent antioxidant analyses, including DPPH•-trapping analysis, 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide radical (PTIO•)-trapping analysis, and •O2 inhibition analysis. In the three analyses, M3OGa always possessed higher IC50 values than those of myricetin. Conclusively, M3OGa and its myricetin aglycone could trap the free radical via a chain reaction comprising of a propagation step and a termination step. At the propagation step, both M3OGa and myricetin could trap radicals through redox-dependent antioxidant pathways. The 3-O-galactosylation process, however, could limit these pathways; thus, M3OGa is an inferior antioxidant compared to its myricetin aglycone. Nevertheless, 3-O-galactosylation has a negligible effect on the termination step. This 3-O-galactosylation effect has provided novel evidence that the difference in the antioxidative activities of phytophenols exists at the propagation step rather than the termination step.


Assuntos
Flavonoides/química , Depuradores de Radicais Livres/química , Galactosídeos/química , Superóxidos/química , Compostos de Bifenilo/antagonistas & inibidores , Óxidos N-Cíclicos/química , Óxidos N-Cíclicos/metabolismo , Dimerização , Flavonoides/metabolismo , Depuradores de Radicais Livres/metabolismo , Radicais Livres , Galactosídeos/metabolismo , Glicosilação , Imidazóis/química , Imidazóis/metabolismo , Cinética , Oxirredução , Picratos/antagonistas & inibidores , Células Vegetais/química , Células Vegetais/metabolismo , Superóxidos/antagonistas & inibidores , Superóxidos/metabolismo
12.
J Biol Chem ; 294(31): 11701-11711, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31186348

RESUMO

Bifidobacteria are exposed to substantial amounts of dietary ß-galactosides. Distinctive preferences for growth on different ß-galactosides are observed within Bifidobacterium members, but the basis of these preferences remains unclear. We previously described the first ß-(1,6)/(1,3)-galactosidase from Bifidobacterium animalis subsp. lactis Bl-04. This enzyme is relatively promiscuous, exhibiting only 5-fold higher efficiency on the preferred ß-(1,6)-galactobiose than the ß-(1,4) isomer. Here, we characterize the solute-binding protein (Bal6GBP) that governs the specificity of the ABC transporter encoded by the same ß-galactoside utilization locus. We observed that although Bal6GBP recognizes both ß-(1,6)- and ß-(1,4)-galactobiose, Bal6GBP has a 1630-fold higher selectivity for the former, reflected in dramatic differences in growth, with several hours lag on less preferred ß-(1,4)- and ß-(1,3)-galactobiose. Experiments performed in the presence of varying proportions of ß-(1,4)/ß-(1,6)-galactobioses indicated that the preferred substrate was preferentially depleted from the culture supernatant. This established that the poor growth on the nonpreferred ß-(1,4) was due to inefficient uptake. We solved the structure of Bal6GBP in complex with ß-(1,6)-galactobiose at 1.39 Å resolution, revealing the structural basis of this strict selectivity. Moreover, we observed a close evolutionary relationship with the human milk disaccharide lacto-N-biose-binding protein from Bifidobacterium longum, indicating that the recognition of the nonreducing galactosyl is essentially conserved, whereas the adjacent position is diversified to fit different glycosidic linkages and monosaccharide residues. These findings indicate that oligosaccharide uptake has a pivotal role in governing selectivity for distinct growth substrates and have uncovered evolutionary trajectories that shape the diversification of sugar uptake proteins within Bifidobacterium.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Bactérias/metabolismo , Bifidobacterium animalis/crescimento & desenvolvimento , Galactosidases/metabolismo , Galactosídeos/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Sequência de Aminoácidos , Proteínas de Bactérias/química , Bifidobacterium animalis/enzimologia , Bifidobacterium animalis/metabolismo , Sítios de Ligação , Domínio Catalítico , Cristalografia por Raios X , Evolução Molecular , Galactosidases/química , Galactosídeos/química , Cinética , Simulação de Dinâmica Molecular , Ligação Proteica , Especificidade por Substrato
13.
Food Chem ; 295: 311-319, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174763

RESUMO

A novel gene aga3027 from the genome of Flammeovirga sp. OC4, isolated from the deep sea, was screened and expressed in Escherichia coli BL21. This gene encoded the genetic information of a potential agarase that consists of 851 amino acids and belongs to 16 ß-agarase family of glycoside hydrolase. Purified recombinant Aga3027 demonstrated the maximum activity of agarase at 40 °C and pH 9.0, displaying excellent thermostability and pH-stability. The agarase retained more than 80% of its maximum activity after incubation at 30-40 °C for 48 h, or after incubation at pH 6.0-9.0 for 60 min, which indicated that this agarase was suitable for industrial applications. Silica gel chromatography was used to purify the hydrolysates of agar treated by agarase from the recombinant Aga3027. The hydrolysates were identified as neoagarotetraose and neoagarohexaose by thin layer chromatography and further confirmed by ion chromatography.


Assuntos
Ágar/química , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/metabolismo , Ágar/metabolismo , Bacteroidetes/enzimologia , Bacteroidetes/genética , Cromatografia em Camada Delgada , Estabilidade Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Galactosídeos/metabolismo , Glicosídeo Hidrolases/genética , Concentração de Íons de Hidrogênio , Hidrólise , Oligossacarídeos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Temperatura
14.
Oxid Med Cell Longev ; 2019: 5459862, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31198492

RESUMO

A new compound, bis(4-hydroxybenzyl)ether mono-ß-L-galactopyranoside (1), was isolated from the rhizome of Gastrodia elata Blume. Its structure was elucidated using extensive spectroscopic analysis, including 1D and 2D NMR, HR-ESI-TOF-MS, and chemical derivatization. Compound 1 extended the replicative lifespan of K6001 and the chronological lifespan of YOM36 yeast strains. To understand the mechanism of action, oxidative stress assessment, reactive oxygen species (ROS) and malondialdehyde (MDA) levels, catalase (CAT) and total glutathione peroxidase (GPx) activity assays, and replicative lifespan assay of sod1, sod2, uth1, and skn7 yeast mutant strains were performed. Results indicated the significant increase in the survival rate of yeast under oxidative stress after treatment with 1. ROS and MDA levels were reduced significantly. Meanwhile, the activity of CAT and GPx was significantly increased. The lifespan of sod1, sod2, uth1, and skn7 mutants of K6001 was not affected by 1. Furthermore, we investigated the gene expression related to longevity after administrating 1. The significant increase of Sir2 and reduction of Uth1 gene expression in the 1-treated group were observed. These results indicated that antioxidative stress played an important role in the antiaging effect of 1; Sir2 and Uth1 genes were involved in antiaging effects of 1.


Assuntos
Envelhecimento/efeitos dos fármacos , Galactosídeos/química , Galactosídeos/farmacologia , Gastrodia/química , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Antioxidantes/farmacologia , Malondialdeído/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética
15.
Chem Commun (Camb) ; 55(54): 7729-7736, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31225574

RESUMO

In the last two decades, the paramount importance of Tumor Associated Carbohydrate Antigens (TACAs) as targets for anticancer vaccine development has been firmly assessed. The Tn antigen is an ideal target for immunotherapy, in that it is masked on normal cells, but exposed on cancer cells. However, it is difficult to elicit an effective and long-lasting response against Tn antigen and other TACAs. Here we report on the Tn antigen analogues developed to boost the latent Tn immune response. Hopefully, the results reported herein will be of help for the rational design of effective TACA-based immunostimulants.


Assuntos
Adjuvantes Imunológicos/química , Antígenos Glicosídicos Associados a Tumores/imunologia , Materiais Biomiméticos/química , Galactosídeos/imunologia , Adjuvantes Imunológicos/síntese química , Animais , Antígenos Glicosídicos Associados a Tumores/química , Materiais Biomiméticos/síntese química , Vacinas Anticâncer/imunologia , Galactosídeos/síntese química , Galactosídeos/química , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/imunologia , Neoplasias/terapia , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/química , Peptídeos Cíclicos/imunologia , Células RAW 264.7
16.
Nutrients ; 11(5)2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31137884

RESUMO

: Aronia melanocarpa are a rich source of anthocyanins that have received considerable interest for their relations to human health. In this study, the anti-adipogenic effect of cyanidin-3-O-galactoside-enriched Aronia melanocarpa extract (AM-Ex) and its underlying mechanisms were investigated in an in vivo system. Five-week-old male C57BL/6N mice were randomly divided into five groups for 8-week feeding with a control diet (CD), a high-fat diet (HFD), or a HFD with 50 (AM-Ex 50), 100 (AM-Ex 100), or 200 AM-Ex (AM-Ex 200) mg/kg body weight/day. HFD-fed mice showed a significant increase in body weight compared to the CD group, and AM-Ex dose-dependently inhibited this weight gain. AM-Ex significantly reduced the food intake and the weight of white fat tissue, including epididymal fat, retroperitoneal fat, mesenteric fat, and inguinal fat. Treatment with AM-Ex (50 to 200 mg/kg) reduced serum levels of leptin, insulin, triglyceride, total cholesterol, and low density lipoprotein (LDL)-cholesterol. Real-time reverse transcription-polymerase chain reaction (RT-PCR) analysis revealed that AM-Ex suppressed adipogenesis by decreasing CCAAT/enhancer binding protein , peroxisome proliferator-activated receptor , sterol regulatory element-binding protein-1c, peroxisome proliferator-activated receptor gamma coactivator-1, acetyl-CoA carboxylase 1, ATP-citrate lyase, fatty acid synthase, and adipocyte protein 2 messenger RNA (mRNA) expressions. These results suggest that AM-Ex is potentially beneficial for the suppression of HFD-induced obesity by modulating multiple pathways associated with adipogenesis and food intake.


Assuntos
Adipogenia/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Antocianinas/farmacologia , Fármacos Antiobesidade/farmacologia , Dieta Hiperlipídica , Galactosídeos/farmacologia , Obesidade/tratamento farmacológico , Photinia , Extratos Vegetais/farmacologia , Ganho de Peso/efeitos dos fármacos , Adipogenia/genética , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/fisiopatologia , Animais , Antocianinas/isolamento & purificação , Fármacos Antiobesidade/isolamento & purificação , Modelos Animais de Doenças , Galactosídeos/isolamento & purificação , Regulação da Expressão Gênica , Camundongos Endogâmicos C57BL , Obesidade/genética , Obesidade/metabolismo , Obesidade/fisiopatologia , Photinia/química , Extratos Vegetais/isolamento & purificação , Transdução de Sinais
17.
PLoS One ; 14(5): e0216546, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31091286

RESUMO

Copper radical alcohol oxidases belonging to auxiliary activity family 5, subfamily 2 (AA5_2) catalyze the oxidation of galactose and galactosides, as well as aliphatic alcohols. Despite their broad applied potential, so far very few AA5_2 members have been biochemically characterized. We report the recombinant production and biochemical characterization of an AA5_2 oxidase from Penicillium rubens Wisconsin 54-1255 (PruAA5_2A), which groups within an unmapped clade phylogenetically distant from those comprising AA5_2 members characterized to date. PruAA5_2 preferentially oxidized raffinose over galactose; however, its catalytic efficiency was 6.5 times higher on glycolaldehyde dimer compared to raffinose. Deep sequence analysis of characterized AA5_2 members highlighted amino acid pairs correlated to substrate range and conserved within the family. Moreover, PruAA5_2 activity spans substrate preferences previously reported for AA5 subfamily 1 and 2 members, identifying possible functional overlap across the AA5 family.


Assuntos
Clonagem Molecular/métodos , Oxirredutases/genética , Oxirredutases/metabolismo , Penicillium/enzimologia , Rafinose/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Galactose/química , Galactosídeos/química , Sequenciamento de Nucleotídeos em Larga Escala , Oxirredução , Penicillium/genética , Filogenia , Engenharia de Proteínas , Proteínas Recombinantes/metabolismo , Análise de Sequência de Proteína
18.
Biosci Biotechnol Biochem ; 83(7): 1227-1238, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31021705

RESUMO

Here we have explored the effect of neoagarotetraose (NAT) on liver injury caused by intense exercise. Our results showed that NAT treatment obviously decreased liver weight (p < 0.01), improved the liver morphological structure, decreased ALT level (p < 0.05) and endotoxin (LPS) (p < 0.01). In addition, NAT could regulate bile acid profiles in feces and serum of mice, which indicated the potential of liver function, suggesting that NAT was effective to relieve intense exercise-induced liver injury. NAT could regulate the expression of colon genes. NAT tended to alter the microbial composition of mice under intense exercise. We uncovered the network interactions between liver traits and microbial communities in NAT treatment mice. Interestingly, our data indicated that intense exercise-induced liver injury may be related to Clostridiales. In summary, these results demonstrated that NAT relieved liver injury induced by intense exercise may be related to gut microbiota.


Assuntos
Galactosídeos/farmacologia , Fígado/lesões , Oligossacarídeos/farmacologia , Condicionamento Físico Animal , Administração Oral , Animais , Colo/metabolismo , Galactosídeos/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligossacarídeos/administração & dosagem , Transcriptoma
19.
PLoS Pathog ; 15(2): e1007589, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30818370

RESUMO

Human T Lymphotropic virus (HTLV) infection can persist in individuals resulting, at least in part, from viral escape of the innate immunity, including inhibition of type I interferon response in infected T-cells. Plasmacytoid dendritic cells (pDCs) are known to bypass viral escape by their robust type I interferon production. Here, we demonstrated that pDCs produce type I interferons upon physical cell contact with HTLV-infected cells, yet pDC activation inversely correlates with the ability of the HTLV-producing cells to transmit infection. We show that pDCs sense surface associated-HTLV present with glycan-rich structure referred to as biofilm-like structure, which thus represents a newly described viral structure triggering the antiviral response by pDCs. Consistently, heparan sulfate proteoglycans and especially the cell surface pattern of terminal ß-galactoside glycosylation, modulate the transmission of the immunostimulatory RNA to pDCs. Altogether, our results uncover a function of virus-containing cell surface-associated glycosylated structures in the activation of innate immunity.


Assuntos
Células Dendríticas/fisiologia , Infecções por HTLV-I/metabolismo , Citocinas , Galactosídeos/metabolismo , Glicosilação , Infecções por HTLV-I/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Vírus Linfotrópico T Tipo 1 Humano/patogenicidade , Vírus Linfotrópico T Tipo 2 Humano/imunologia , Vírus Linfotrópico T Tipo 2 Humano/patogenicidade , Humanos , Imunidade Inata/fisiologia , Interferon Tipo I/imunologia , Interferon-alfa/imunologia , Interferon-alfa/metabolismo , Células Jurkat , Linfócitos T/imunologia , Linfócitos T/fisiologia
20.
Appl Biochem Biotechnol ; 188(4): 1077-1095, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30788710

RESUMO

Agar, a major polysaccharide of red algal cells, is degraded by ß-agarases into neoagarobiose, which is further hydrolyzed into the monomers, D-galactose and 3,6-anhydro-L-galactose, by 1,3-α-3,6-anhydro-L-galactosidases including α-1,3-L-neoagarooligasaccharide hydrolase (α-NAOSH). A novel cold-adapted alkaline α-NAOSH, Ahg558, consisting of 359 amino acids (40.8 kDa) was identified from Gayadomonas joobiniege G7. It was annotated as a glycosyl hydrolase family 43 based on genomic sequence analysis, showing 84% and 74% identities with the characterized α-NAOSHs from Agarivorans gilvus WH0801 and Saccharophagus degradans 2-40, respectively. The recombinant Ahg558 (rAhg558) purified from Escherichia coli formed dimers and cleaved α-1,3 glycosidic bonds at the non-reducing ends of the neoagarobiose, neoagarotetraose, and neoagarohexaose, which was confirmed by thin-layer chromatography and mass spectrometry. The optimum pH and temperature for rAhg558 activity were 9.0 and 30 °C, respectively. Unusually, it retained over 93% activity in a broad range of temperatures between 0 and 40 °C and over 73% in a broad range of pH between pH 6.0 and pH 9.0, indicating it is a unique cold-adapted alkaline exo-acting α-NAOSH. Its enzymatic activity was dependent on Mn2+ ions. Km and Vmax values toward neoagarobiose were 2.6 mg/mL (8.01 mM) and 133.33 U/mg, respectively.


Assuntos
Galactosidases/metabolismo , Cromatografia em Camada Delgada , Clonagem Molecular , Dissacarídeos/metabolismo , Galactosídeos/metabolismo , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Oligossacarídeos/metabolismo
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