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1.
Crit Rev Food Sci Nutr ; : 1-19, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34494479

RESUMO

Food allergy is a serious health problem affecting more than 10% of the human population worldwide. Medical treatments for food allergy remain limited because immune therapy is risky and costly, and anti-allergic drugs have many harmful side effects and can cause drug dependence. In this paper, we review natural bioactive substances capable of alleviating food allergy. The sources of the anti-allergic substances reviewed include plants, animals, and microbes, and the types of substances include polysaccharides, oligosaccharides, polyphenols, phycocyanin, polyunsaturated fatty acids, flavonoids, terpenoids, quinones, alkaloids, phenylpropanoids, and probiotics. We describe five mechanisms involved in anti-allergic activities, including binding with epitopes located in allergens, affecting the gut microbiota, influencing intestinal epithelial cells, altering antigen presentation and T cell differentiation, and inhibiting the degranulation of effector cells. In the discussion, we present the limitations of existing researches as well as promising advances in the development of anti-allergic foods and/or immunomodulating food ingredients that can effectively prevent or alleviate food allergy. This review provides a reference for further research on anti-allergic materials and their hyposensitizing mechanisms.

2.
Food Chem ; 342: 128221, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33092920

RESUMO

Goat milk oligosaccharides represent an unexplored multi-functional ingredient for the dairy industry. Here, we qualitatively and quantitatively compared the N/O-glycome at different lactation stages via online hydrophilic interaction chromatography-tandem mass spectrometry. Complex N-glycans and high mannose N-glycans constituted 82.1% and 17.9% of the glycan pool, respectively. N-glycans with isomers containing non-bisected antenna complex structures accounted for 30.8%. N-glycans modified with Neu5Ac, Neu5Gc and fucosylated were 3.7%, 5.3% and 35.3%. The triantennary trifucosylated complex N-glycan (H5N5F3) was reported for the first time. A comparison between colostrum and mature milk revealed a 1.20-fold decrease in total N-glycans and 1.66-fold decrease in fucosylation with ongoing lactation, echoing the trend in human milk. Similarly, Neu5Ac- and Neu5Gc-modified sialylation decreased by 1.69 and 3.62 times, respectively. In the O-glycome, 46.2% of structures were O-linked core 1, 23.1% were O-linked core 2, 7.7% were O-linked core 3 and core 4. As lactation progressed, overall O-glycans content decreased by 1.26-fold. Unlike human milk, Neu5Ac- and Neu5Gc-modified sialylation increased by 4.4 and 2 times, respectively. These findings will facilitate research on the structure-function relationship of goat milk oligosaccharides and the development of formula food targeting different age groups.


Assuntos
Glicoproteínas/química , Glicoproteínas/metabolismo , Cabras , Lactação , Animais , Colostro/metabolismo , Feminino , Glicosilação , Humanos , Gravidez
3.
Food Chem ; 339: 127866, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32858386

RESUMO

Sialylated N-glycans are an integral component of whey proteins in human milk and play an irreplaceable role in infant growth and development. Currently, there are few studies on quantitative comparison of sialylated N-glycans in milk obtained at different lactation stages. Here, a preliminary isomer-specific quantification of whey sialylated N-glycans of human colostrum milk (CM) and mature milk (MM) was performed by using our recently developed glycoqueuing strategy. Such a preliminary comparison revealed that the whey sialylated N-glycan content was 86.4% lower in MM than in CM. Twenty-three α2,6-linked sialylated N-glycan isomers were detected with no α2,3-linked isomer observed. For the first time, three mono-sialylated and four bi-sialylated glycan isomers were reported. With the prolongation of lactation, the relative abundance of mono-sialylated glycans increased, whilst the relative abundance of bi-sialylated glycans decreased significantly. These findings contribute to the understanding of the structure-function relationship of sialylated N-glycans in the human whey fraction.


Assuntos
Colostro/química , Glicoproteínas/química , Leite Humano/química , Ácido N-Acetilneuramínico/química , Polissacarídeos/química , Análise de Sequência , Proteínas do Soro do Leite/química , Animais , Feminino , Humanos , Isomerismo , Lactação , Gravidez
4.
EMBO Rep ; 21(12): e51444, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33063473

RESUMO

PD-1 is a highly glycosylated inhibitory receptor expressed mainly on T cells. Targeting of PD-1 with monoclonal antibodies (MAbs) to block the interaction with its ligand PD-L1 has been successful for the treatment of multiple tumors. However, polymorphisms at N-glycosylation sites of PD-1 exist in the human population that might affect antibody binding, and dysregulated glycosylation has been observed in the tumor microenvironment. Here, we demonstrate varied N-glycan composition in PD-1, and show that the binding affinity of camrelizumab, a recently approved PD-1-specific MAb, to non-glycosylated PD-1 proteins from E. coli is substantially decreased compared with glycosylated PD-1. The structure of the camrelizumab/PD-1 complex reveals that camrelizumab mainly utilizes its heavy chain to bind to PD-1, while the light chain sterically inhibits the binding of PD-L1 to PD-1. Glycosylation of asparagine 58 (N58) promotes the interaction with camrelizumab, while the efficiency of camrelizumab to inhibit the binding of PD-L1 is substantially reduced for glycosylation-deficient PD-1. These results increase our understanding of how glycosylation affects the activity of PD-1-specific MAbs during immune checkpoint therapy.


Assuntos
Escherichia coli , Receptor de Morte Celular Programada 1 , Anticorpos Monoclonais Humanizados , Escherichia coli/metabolismo , Glicosilação , Humanos , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo
5.
Foods ; 9(10)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096617

RESUMO

As the one of the major allergens in peanut, the allergenicity of Ara h 1 is influenced by its intrinsic structure, which can be modified by different processing. However, molecular information in this modification has not been clarified to date. Here, we detected the influence of microbial transglutaminase (MTG) catalyzed cross-linking on the recombinant peanut protein Ara h 1 (rAra h 1). Electrophoresis and spectroscopic methods were used to analysis the structural changes. The immunoreactivity alterations were characterized by enzyme linked immunosorbent assay (ELISA), immunoblotting and degranulation test. Structural features of cross-linked rAra h 1 varied at different reaction stages. Hydrogen bonds and disulfide bonds were the main molecular forces in polymers induced by heating and reducing. In MTG-catalyzed cross-linking, ε-(γ-glutamyl) lysine isopeptide bonds were formed, thus inducing a relatively stable structure in polymers. MTG catalyzed cross-linking could modestly but significantly reduce the immunoreactivity of rAra h 1. Decreased content of conserved secondary structures led to a loss of protection of linear epitopes. Besides, the reduced surface hydrophobic index and increased steric hindrance of rAra h 1 made it more difficult to bind with antibodies, thus hindering the subsequent allergic reaction.

6.
Food Funct ; 11(9): 7415-7420, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32966484

RESUMO

Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread around the world at an unprecedented rate. In the present study, 4 marine sulfated polysaccharides were screened for their inhibitory activity against SARS-CoV-2, including sea cucumber sulfated polysaccharide (SCSP), fucoidan from brown algae, iota-carrageenan from red algae, and chondroitin sulfate C from sharks (CS). Of them, SCSP, fucoidan, and carrageenan showed significant antiviral activities at concentrations of 3.90-500 µg mL-1. SCSP exhibited the strongest inhibitory activity with IC50 of 9.10 µg mL-1. Furthermore, a test using pseudotype virus with S glycoprotein confirmed that SCSP could bind to the S glycoprotein to prevent SARS-CoV-2 host cell entry. The three antiviral polysaccharides could be employed to treat and prevent COVID-19.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Feófitas/química , Polissacarídeos/farmacologia , Rodófitas/química , Pepinos-do-Mar/química , Animais , Antivirais/química , Betacoronavirus/fisiologia , COVID-19 , Infecções por Coronavirus/virologia , Humanos , Pandemias , Pneumonia Viral/virologia , Polissacarídeos/química , SARS-CoV-2 , Tubarões , Sulfatos/química , Internalização do Vírus/efeitos dos fármacos
7.
Fungal Genet Biol ; 144: 103440, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32758529

RESUMO

Protein O-mannosyltransferases (PMTs) initiate O-mannosylation of proteins in the ER. Trichoderma reesei strains displayed a single representative of each PMT subfamily, Trpmt1, Trpmt2 and Trpmt4. In this work, two knockout strains ΔTrpmt1and ΔTrpmt4were obtained. Both mutants showed retarded growth, defective cell walls, reduced conidiation and decreased protein secretion. Additionally, the ΔTrpmt1strain displayed a thermosensitive growth phenotype, while the ΔTrpmt4 strain showed abnormal polarity. Meanwhile, OETrpmt2 strain, in which the Trpmt2 was over-expressed, exhibited increased conidiation, enhanced protein secretion and abnormal polarity. Using a lectin enrichment method and MS/MS analysis, 173 O-glycoproteins, 295 O-glycopeptides and 649 O-mannosylation sites were identified as the targets of PMTs in T. reesei. These identified O-mannoproteins are involved in various physiological processes such as protein folding, sorting, transport, quality control and secretion, as well as cell wall integrity and polarity. By comparing proteins identified in the mutants and its parent strain, the potential specific protein substrates of PMTs were identified. Based on our results, TrPMT1 is specifically involved inO-mannosylation of intracellular soluble proteins and secreted proteins, specially glycosidases. TrPMT2 is involved inO-mannosylation of secreted proteins and GPI-anchor proteins, and TrPMT4 mainly modifies multiple transmembrane proteins. The TrPMT1-TrPMT4 complex is responsible for O-mannosylation of proteins involved in cell wall integrity. Overexpression of TrPMT2 enhances protein secretion, which might be a new strategy to improve expression efficiency in T. reesei.


Assuntos
Proteínas Fúngicas/biossíntese , Hypocreales/genética , Manosiltransferases/genética , Morfogênese/genética , Parede Celular/genética , Proteínas Fúngicas/genética , Glicosilação , Hypocreales/enzimologia , Fenótipo , Transporte Proteico/genética , Espectrometria de Massas em Tandem
8.
Anal Chem ; 92(17): 11644-11653, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32709191

RESUMO

The structure of chondroitin sulfate oligosaccharides (CSOs), especially their sulfation pattern, has been found to be closely related with many biological pathways and diseases. However, detailed functional analysis such as their interaction with glycan binding proteins (GBPs) has been lagging, presumably due to the unavailability of well-defined, diverse structures. Besides challenging chemical and enzymatic synthesis, this is also due to the challenges in their purification at the isomer level and structural analysis owing to their instability, structural complexity, and low mass spectrometry detection sensitivity. Herein, we first used recycling preparative HPLC to separate and purify shark CS tetrasaccharide component labeled by a bifunctional fluorescent linker 2-amino-N-(2-aminoethyl)benzamide (AEAB) at the isomer level. Then, each isomer was derivatized through a multistage procedure including N-acetylation, carboxyl amidation, permethylation, and desulfation with silylating reagent. Structural analysis of each derivatized isomer was performed with ESI-MSn in positive ion mode. A total of 16 isomers of CSO-AEAB were isolated, with a minimum mass component of 0.007 mg and a maximum mass component of 17.53 mg, of which 10 isomers (>90 µg) were structurally analyzed. This preparation and structure analysis of CSOs lay the foundation for further study of the structure-activity relationship of CSOs.


Assuntos
Produtos Biológicos/química , Sulfatos de Condroitina/química , Oligossacarídeos/química , Acetilação , Amidas/química , Benzamidas/química , Butilaminas/química , Cromatografia Líquida de Alta Pressão , Isomerismo , Metilação , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
9.
Food Funct ; 11(6): 5595-5606, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32525182

RESUMO

Antibiotic treatment, as an important therapeutic intervention, can cause damage to the host microbiome and the intestinal mucosal barrier. In order to find a way to alleviate the side effects of antibiotics, the present study investigated the effects of fucoidan (ANP) isolated from Ascophyllum nodosum on gut microbiota dysbiosis and colonic inflammation induced by ciprofloxacin-metronidazole (CiMe) in C57BL/6J mice. Our results showed that dietary ANP prevented colon shortening, alleviated the colonic tissue damages, and partially reversed the alteration of gut microbiota by increasing the abundance of potentially beneficial bacteria, e.g., Ruminococcaceae_UCG_014 and Akkermansia and decreasing the abundance of harmful bacteria, e.g., Proteus and Enterococcus. ANP also suppressed the overproduction of TNF-α, IL-1ß, and IL-6 and promoted the expression of IL-10. In addition, ANP reversed the decreased production of short-chain fatty acids in CiMe-treated mice. Furthermore, correlation analysis indicated the presence of critical gut microbiota, which played important roles in reducing the inflammation-related indices. Thus, the present study suggests that fucoidan isolated from Ascophyllum nodosum is effective in providing protection against the negative effects of antibiotics on gut microbiota and colonic health.


Assuntos
Ascophyllum/metabolismo , Disbiose/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Animais , Antibacterianos/efeitos adversos , Bactérias/genética , Clostridiales , Colo/metabolismo , Colo/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Disbiose/microbiologia , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal/genética , Inflamação/induzido quimicamente , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
10.
Food Chem ; 329: 127042, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32504916

RESUMO

Polysaccharides are a major active component of Porphyra haitanensis, which is an important food source in many countries. Four different molecular-weight fractions, namely PHPD-I (329 kDa), PHPD-II (203 kDa), PHPD-III (128 kDa), and PHPD-IV (10 kDa), were obtained from P. haitanensis polysaccharides by degradation using the H2O2/ascorbic acid system. PHPD-IV elicited the highest level of antioxidant and immunostimulatory activity among the four fractions. PHPD-IV was purified by DEAE-cellulose column and five fractions were obtained, designated PHPD-IV-1-PHPD-IV-5. PHPD-IV-4 displayed the greatest biological activity by up-regulating the phosphorylation of MAPK signalling molecules. PHPD-IV-4 was further purified, and its structure was characterized by monosaccharide composition and 1/2D-NMR analysis. The result revealed that PHPD-IV-4 was repeated units of â†’ 3) ß-d-galactose (1 â†’ 4) 3, 6-anhydro-α-l-galactose (1→, and â†’ 3) ß-d-galactose (1 â†’ 4) α-l-galactose-6-S (1→. This study provides a theoretical basis for the utilisation and structure-activity assessment of P. haitanensis polysaccharides.


Assuntos
Polissacarídeos/química , Porphyra/química , Antioxidantes/química , Ácido Ascórbico/química , Galactose/química , Peróxido de Hidrogênio/química , Espectroscopia de Ressonância Magnética , Peso Molecular
11.
Life Sci ; 256: 117893, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32502539

RESUMO

AIMS: To investigate the effect and underlying mechanism of melittin and tripartite motif (TRIM) family in human embryonic lung fibroblast (HELF). MATERIALS AND METHODS: Lentiviral RNA interference vector and lentiviral overexpression vector were constructed and packaged by transfecting 293T cells; the proliferation of HELF was examined using Cell Counting Kit 8; Western blot and qRT-PCR were performed to examine protein and mRNA expression; the interaction with protein phosphatase magnesium-dependent 1A (PPM1A) was examined by Co-immunoprecipitation. KEY FINDINGS: Compared with the control group, the mRNA expression of the TRIM6, TRIM8 and TRIM47 in the IPF group significantly increased. Melittin inhibited the mRNA expression and protein expression levels of TRIM47, the HELF proliferation, the hydroxyproline levels, and the phosphorylation of Smad2/3; the interference of TRIM47 inhibited the protein expression of Vimentin, α-SMA, CTGF, the phosphorylation of Smad2/3 and the synthesis of hydroxyproline; TRIM47 overexpression elevated the phosphorylation of Smad2/3, induced ubiquitination of PPM1A and decreased the expression level of PPM1A, while TRIM47 RNA interference reversed this result. SIGNIFICANCE: Melittin has anti-fibrotic effect in HELF by directly reducing the phosphorylation of Smad2/3 or indirectly reducing the phosphorylation of Smad2/3 by decreasing the expression levels of TRIM47 whose overexpression induces ubiquitination of PPM1A.


Assuntos
Proteínas de Transporte/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Pulmão/embriologia , Meliteno/farmacologia , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Transdução de Sinais , Actinas/metabolismo , Proteínas de Transporte/sangue , Proliferação de Células/efeitos dos fármacos , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fibroblastos/efeitos dos fármacos , Fibrose , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hidroxiprolina/metabolismo , Proteínas de Neoplasias/sangue , Proteínas Nucleares/sangue , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 2C/metabolismo , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Ubiquitinação/efeitos dos fármacos , Vimentina/metabolismo
12.
J Am Chem Soc ; 142(16): 7404-7412, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32239931

RESUMO

Protein-specific glycoform analysis is essential for the thorough understanding of cellular chemistry and signaling but presents a significant assay challenge for small-sized, free-floating exosomes, ubiquitous regulators of cellular physiological functions and mediators of intercellular communication. We report herein a quantitative localized analysis (QLA) method for the first-time achievement of a protein-specific glycosignature assay on these important extracellular vesicles. The integration of localized chemical remodeling and quantitative electrochemistry allows the proof-of-concept QLA examination of exosomal mucin 1 (MUC1)-specific terminal galactose/N-acetylgalactosamine (Gal/GalNAc). In combination with sialic acid (Sia) cleavage manipulation for the exposure of originally capped Gal/GalNAc, QLA has revealed distinct MUC1-specific sialylation capping ratios for MCF-7 and MDA-MB-231 exosomes, as well as when compared to parent cells. These findings suggest a useful noninvasive indicator for subtyping cancer cells and exosome secretion as a likely venue for the preservation of cellular compositional and functional integrity. The QLA method also permits dynamic monitoring of changes in the exosomal MUC1-specific sialylation capping ratio, enabling the distinction of biogenesis pathways of exosomes.


Assuntos
Exossomos/química , Vesículas Extracelulares/metabolismo , Neoplasias/genética , Humanos , Transdução de Sinais
13.
J Chromatogr A ; 1620: 461001, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32151415

RESUMO

Mass spectrum (MS) is one of the most commonly used tools for qualitative and quantitative analysis of glycans. However, due to the complexity of biological samples and the low ionization efficiency of glycans, these need to be purified and derivatized prior to MS analysis. Existing purification strategies require a combination of multiple methods and are cumbersome to operate. Here, we propose a new method for the purification of glycoprotein N/O-glycans and their derivatives using a hand-packed absorbent cotton hydrophilic interaction chromatography column (HILIC). The method's reliability and applicability were verified by purifying N/O-glycans and the derivatives of standard glycoproteins, such as chicken albumin and porcine stomach mucin. Stable isotope labelling was used to compare the glycans' recovery following different purification methods. Absorbent cotton HILIC was also successfully applied for the analysis of human serum and fetal bovine serum glycoprotein N-glycans. Finally, testing revealed high binding capacity (9 mg/g-1 maltohexaose/absorbent cotton) and good recovery (average recovery was 91.7%) of glycans. Compared with traditional procedures, the proposed purification method offers considerable advantages, such as simplicity, high efficiency, economy, universality, and broad applicability for the pretreatment of glycans and their derivatives in biological samples prior to MS analysis.


Assuntos
Cromatografia/métodos , Polissacarídeos/isolamento & purificação , Animais , Galinhas , Fibra de Algodão , Glicoproteínas/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Marcação por Isótopo , Espectrometria de Massas , Mucinas/química , Polissacarídeos/sangue , Polissacarídeos/química , Suínos
14.
Glycoconj J ; 37(2): 165-174, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32026252

RESUMO

The study of carbohydrates requires large amounts of glycans. N-Glycans can be synthesized but generating large quantities of N-glycans with diverse structures remains difficult. In this study, we aimed to obtain large amounts of glycans using an optimized procedure. Two types of reductive N-glycans were released from chicken egg albumin (ovalbumin) and soy protein using an ammonia catalysis method and labeled with benzenesulfonyl hydrazide (BSH). After preliminary separation by preparative HPLC, N-glycan-BSH components were de-labeled separately and reducing N-glycans were recovered. The de-labeled reducing N-glycans were derived with different labeling reagents and further separated and purified with two/multi-dimensional HPLC for various studies. We selected the bifunctional reagent 2-amino-N-(2-aminoethyl)-benzamide (AEAB) as a labeling reagent combined with C18 column for two-dimensional HPLC separation. A total of 21 and 8 N-glycan-AEAB conjugates were obtained from ovalbumin and soy protein, respectively. A reactive primary alkylamine of N-glycan-AEAB conjugates can be effectively immobilized on microarray surfaces, allowing for subsequent functional studies of glycans.


Assuntos
Polissacarídeos/síntese química , Amônia/química , Benzamidas/química , Benzenossulfonatos/química , Catálise , Cromatografia Líquida de Alta Pressão/métodos , Ovalbumina/química , Proteínas de Soja/química
15.
Int J Biol Macromol ; 149: 639-650, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-31991207

RESUMO

Previous studies have shown that crude polysaccharides from the Lycium barbarum fruit could inhibit cancer cell growth, but the major effective constituents are yet to be identified. In this study, we compared the effects of L. barbarum fruit polysaccharide fractions on the growth of hepatoma cells (SMMC-7721 and HepG2), cervical cancer cells (HeLa), gastric carcinoma cells (SGC-7901), and human breast cancer cells (MCF-7). LBGP-I-3 showed stronger inhibitory effects on MCF-7 cells (cell viability of 48.96%) than SMMC-7721 (cell viability of 78.91%) and HeLa cells (cell viability of 55.94%), and had no effect on HepG2 and SGC-7901 cells. In addition, LBGP-I-3 had no inhibitory effect on normal liver cells (L02, cell viability of 115.58%). Investigation of the underlying mechanism suggested that LBGP-I-3 inhibited the growth of cancer cells by cell cycle arrest and apoptosis. LBGP-I-3 arrested the cell cycle at the G0/G1 phase, altered mitochondrial function, activated oxidative stress, and regulated the MAPK signaling pathway to induce apoptosis. Thus, LBGP-I-3 may be a potential functional food ingredient for the prevention of cancer without toxicity to normal cells in vitro. These results could help further elucidate the structure-activity relationship of L. barbarum fruit polysaccharides and functional food development.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Frutas/química , Galactanos/química , Galactanos/farmacologia , Lycium/química , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , China , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Células HeLa/efeitos dos fármacos , Células Hep G2/efeitos dos fármacos , Humanos , Fígado , Fitoterapia , Polissacarídeos/química , Polissacarídeos/farmacologia , Neoplasias Gástricas , Neoplasias do Colo do Útero
16.
J Agric Food Chem ; 68(7): 2174-2182, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31985220

RESUMO

Goat milk oligosaccharides are complex carbohydrates with a variety of biological functions. Free oligosaccharides from goat milk show more similarity to human milk than cow milk. At present, changes in goat milk glycoconjugates at different parities remain poorly studied. Herein, we qualitatively and quantitatively compared the goat milk glycoprotein N/O-glycome at different parities using a stable isotope labeling followed by electrospray ionization mass spectrometry and online hydrophilic interaction chromatography. N-Glycans were mainly fucosylated and nonfucosylated nonsialylated, and both fucosylation and sialylation gradually increased with parity, amounting (at the third parity) to 1.25 times and 3.3 times those of the first parity, respectively. O-Glycans were mostly nonfucosylated and nonsialylated, and sialylation increased with increasing parity, and Neu5Ac-sialylated was up to 9 times higher in the third parity than in the first parity, whereas Neu5Gc-sialylated was 5.5 times higher. This study provides a reference for exploring an alternative milk source closest to human milk and for the development of humanized formula milk.


Assuntos
Colostro/química , Polissacarídeos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Feminino , Glicosilação , Cabras , Humanos , Leite Humano/química , Oligossacarídeos/química , Espectrometria de Massas em Tandem
17.
Int J Biol Macromol ; 152: 1047-1055, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31751707

RESUMO

Biological functions of chondroitin sulfate, including anti-oxidation and anti-inflammation, are associated with its molecular weight. This study aimed to evaluate the correlation between antioxidant activity and molecular weights of chondroitin sulfate derived from bovine nasal cartilage (BCS). BCS extracted by compound enzymatic method was further purified via DEAE-cellulose column separation to obtain BCS-II (129.4 kDa), which was further degraded by H2O2-Vc to obtain four subfractions: BCS-II-1 (92.7 kDa), BCS-II-2 (54.1 kDa), BCS-II-3 (26.3 kDa), and BCS-II-4 (19.7 kDa). Changes in the physicochemical properties of BCS-II before and after degradation were compared via FT-IR, NMR and monosaccharide composition analysis. Finally, antioxidant activities of BCS-II and its subfractions BCS-II-1-4 were compared. Our results showed that the H2O2-Vc system did not disrupt the primary functional group of BCS-II, with no significant change in sulfate content between BCS-II and its degraded fractions; however, uronic acid levels increased in degraded fractions when compared with BCS-II. In vitro, BCS-II-4 displayed the lowest molecular weight and had the strongest antioxidant activity. Therefore, the antioxidant activity of chondroitin sulfate in vitro is robustly associated with its molecular weight, and low-molecular-weight chondroitin sulfate can be used as an antioxidant in the food and pharmaceutical industries and other sectors.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Sulfatos de Condroitina/química , Cartilagens Nasais/química , Animais , Bovinos , Peróxido de Hidrogênio/química , Peso Molecular , Nariz/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Ácidos Urônicos/química
18.
J Agric Food Chem ; 68(5): 1207-1212, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31755264

RESUMO

Human noroviruses (HuNoVs) are among the main pathogens causing acute nonbacterial gastroenteritis. Histo-blood group antigens (HBGAs) are widely accepted receptors for HuNoV specific binding. HBGA-like substances in produce are also considered as the critical ligands for capture of HuNoVs. However, the composition of viral ligands from food substrates remains unknown. In this study, an oligosaccharide (H2N2F2) was captured and isolated from romaine lettuce extract by a bacterial surface display system. Using electrospray ionization mass spectrometry and tandem mass spectrometry, it was shown that H2N2F2 was most likely to be a chimera of type A, H, and Lewis a HBGAs. The composition was consistent with our ELISA results using a panel of monoclonal antibodies against HBGAs. Our results revealed a possible interaction mechanism between HuNoVs and romaine lettuce. Better understanding of the interaction of HuNoVs with easily contaminated produce will ultimately aid in the control of and reduction in disease outbreaks.


Assuntos
Antígenos de Plantas/metabolismo , Antígenos de Grupos Sanguíneos/metabolismo , Alface/virologia , Norovirus/fisiologia , Receptores Virais/metabolismo , Ligação Viral , Antígenos de Plantas/química , Antígenos de Plantas/genética , Antígenos de Grupos Sanguíneos/química , Antígenos de Grupos Sanguíneos/genética , Infecções por Caliciviridae/genética , Infecções por Caliciviridae/metabolismo , Infecções por Caliciviridae/virologia , Humanos , Alface/química , Alface/genética , Alface/metabolismo , Espectrometria de Massas , Norovirus/genética , Oligossacarídeos/química , Oligossacarídeos/genética , Oligossacarídeos/metabolismo , Ligação Proteica , Receptores Virais/química , Receptores Virais/genética
19.
Fungal Genet Biol ; 134: 103285, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648060

RESUMO

Protein O-mannosyltransferases (PMTs) have been identified in fungi but not in plants and nematodes, which makes PMTs become attractive targets for developing a new strategy against phytopathogens. Three PMTs have been identified in Fusarium oxysporum, a fungal pathogen that causes vascular wilt in a broad range of economical crops. By deletion or suppression of the pmt genes, we showed that all mutants displayed retarded growth, reduced conidiation, cell wall defects, ER stress and attenuated virulence in F. oxysporum f.sp. cucumerinum. In addition, the Δpmt1 exhibited reduced thermotolerance, while the Δpmt4 and the pmt2 conditional mutant exhibited abnormal polarized growth. Comparative glycoproteome analysis of these pmt mutants revealed that PMTs preferentially modified random coils with flanking regions rich in Ser, Thr, Ala, Glu, Asp and Lys at the stem region of membrane proteins, the N-terminal region close to signal peptide of secreted proteins, or surface of soluble proteins. PMT1 specifically acted on nuclear proteins and proteins that are responsible for protein folding, which might contribute to thermotolerance. PMT4 specifically acted on the membrane and soluble proteins in secretory pathways, especially the GPI anchoring pathway, which might contribute to synthesis and transportation of GPI anchored proteins and thus polarized growth. PMT2 was responsible for modification of proteins that are required for protein folding and cell wall synthesis, which might make PMT2 essential. Our results gave an insight to understanding of the roles of each O-mannosyltransferase in F. oxysporum f.sp. cucumerinum and provide a new perspective to prevent Fusarium wilt.


Assuntos
Proteínas Fúngicas/genética , Fusarium/enzimologia , Fusarium/patogenicidade , Genes Fúngicos , Manosiltransferases/genética , Parede Celular/metabolismo , Parede Celular/patologia , Produtos Agrícolas/microbiologia , Cucumis sativus/microbiologia , Proteínas Fúngicas/metabolismo , Fusarium/genética , Deleção de Genes , Organismos Geneticamente Modificados , Fenótipo , Doenças das Plantas/microbiologia , Dobramento de Proteína , Sementes/microbiologia , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Virulência/genética
20.
Int J Biol Macromol ; 143: 255-264, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31760031

RESUMO

Polygonatum sibiricum (PS) is a traditional Chinese herb used in both food and medicine with great bioactivity. The wine-processed pieces of PS are the main form for clinical application, while research has focused on the polysaccharides of their crude form. This study evaluated the physicochemical properties and immunological activities of water-soluble polysaccharides from both crude (PSPC) and wine-processed PS (PSPW). PSPC and PSPW had significant differences in their physicochemical properties. PSPC was mainly composed of galactose, mannose, glucose, and galacturonic acid, in molar ratios of 29.63:36.10:15.09:10.20, while PSPW was mainly composed of galactose, mannose, and galacturonic acid, in molar ratios of 78.77:5.50:13.84. Both kinds of polysaccharides can enhance the cells viability, phagocytic capacity, acid phosphatase activity, and NO production of RAW264.7 cells. We found that PSPC and PSPW enhanced the immune functions of the immunosuppressive model for spleen deficient mice and reversed the decline of the secretions of IL-2, IL-6, TNF-α, and IFN-γ to a normal range. The PSPW showed more potent immunological activities than PSPC. The results of the study identify the importance of wine-processing for PS and provide application foundations for the further development of PSPW as a functional food.


Assuntos
Polygonatum/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Galactose/química , Glucose/química , Manose/química , Camundongos , Polygonatum/imunologia , Polissacarídeos/imunologia , Células RAW 264.7 , Vinho/microbiologia
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