RESUMO
Food provides energy and various nutrients and is the most important substance for the survival of living beings. However, for allergic people, certain foods cause strong reactions, and sometimes even cause shock or death. Food allergy has been recognized by the World Health Organization (WHO) as a major global food safety issue which affect the quality of life of nearly 5% of adults and 8% of children, and the incidence continues to rise but there is no effective cure. Drug alleviation methods for food allergies often have shortcomings such as side effects, poor safety, and high cost. At present, domestic and foreign scientists have turned to research and develop various new, safe and efficient natural sources of hypoallergenic or anti-allergic drugs or foods. There are many kinds of anti-allergic substances obtained from the plants and animals have been reported. Besides, probiotics and bifidobacteria also have certain anti-allergic effects. Of all the sources of anti-allergic substances, the ocean is rich in effective active substances due to its remarkable biodiversity and extremely complex living environment, and plays a huge role in the field of anti-food allergy. In this paper, the anti-food allergic bioactive substances isolated from marine organisms encompassing marine microbial, plant, animal sources and their mechanism were reviewed and the possible targets of anti-allergic substances exerting effects are illustrated by drawing. In addition, the development prospects of marine anti-allergic market are discussed and forecasted, which can provide reference for future research on anti-allergic substances.
Assuntos
Antialérgicos/farmacologia , Antialérgicos/uso terapêutico , Organismos Aquáticos/química , Hipersensibilidade Alimentar/tratamento farmacológico , Hipersensibilidade Alimentar/prevenção & controle , Alimentos/efeitos adversos , Alérgenos/efeitos adversos , Alérgenos/imunologia , Animais , Antialérgicos/análise , Hipersensibilidade Alimentar/imunologia , Humanos , Qualidade de VidaRESUMO
BACKGROUND: Enzymatic treatment of allergenic protein can alter their functional properties under a mild reaction condition due to specificity of enzymes. Phenolic compounds act as mediators and enhance the crosslinking reactions. The study aimed to assess the changes in the structure and immunoglobulin G (IgG) binding capacity of turbot parvalbumin (PV) upon crosslinking with tyrosinase (Tyr) in the absence and presence of caffeic acid. RESULTS: Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed the appearance of higher molecular weight bands (24, 36 kDa) in the crosslinked PV. The secondary structure of crosslinked PV became loosened and disordered. The results of intrinsic fluorescence and ultraviolet absorption spectral analyses, as well as surface hydrophobicity and free amino group analyses also revealed structural changes. As observed by western blot analysis, the intensity of the PV bands reduced upon Tyr treatment, indicating reduced binding of specific IgG to PV. Moreover, the indirect ELISA (enzyme-linked immunosorbent assay) analysis confirmed that the IgG binding ability of crosslinked PV was reduced 34.94%. CONCLUSION: Enzymatic treatment mitigated the allergenicity of fish PV, which was closely related to the alterations in the conformational structure. This treatment showed potential for developing hypoallergenic fish products under mild reaction conditions. © 2019 Society of Chemical Industry.
Assuntos
Alérgenos/imunologia , Ácidos Cafeicos/química , Reagentes de Ligações Cruzadas/química , Proteínas de Peixes/imunologia , Linguados/imunologia , Monofenol Mono-Oxigenase/química , Parvalbuminas/imunologia , Alérgenos/genética , Animais , Biocatálise , Proteínas de Peixes/química , Imunoglobulina G/imunologia , Parvalbuminas/químicaRESUMO
Targeting mitochondrial respiration has been documented as an effective therapeutic strategy in cancer. However, the impact of mitochondrial respiration inhibition on cervical cancer cells are not well elucidated. Using a panel of cervical cancer cell lines, we show that an existing drug atovaquone is active against the cervical cancer cells with high profiling of mitochondrial biogenesis. Atovaquone inhibited proliferation and induced apoptosis with varying efficacy among cervical cancer cell lines regardless of HPV infection, cellular origin and their sensitivity to paclitaxel. We further demonstrated that atovaquone acts on cervical cancer cells via inhibiting mitochondrial respiration. In particular, atovaquone specifically inhibited mitochondrial complex III but not I, II or IV activity, leading to respiration inhibition and energy crisis. Importantly, we found that the different sensitivity of cervical cancer cell lines to atovaquone were due to their differential level of mitochondrial biogenesis and dependency to mitochondrial respiration. In addition, we demonstrated that the in vitro observations were translatable to in vivo cervical cancer xenograft mouse model. Our findings suggest that the mitochondrial biogenesis varies among patients with cervical cancer. Our work also suggests that atovaquone is a useful addition to cervical cancer treatment, particularly to those with high dependency on mitochondrial respiration.
Assuntos
Mitocôndrias/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/terapia , Atovaquona/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Respiração Celular/efeitos dos fármacos , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético , Feminino , Humanos , Mitocôndrias/efeitos dos fármacos , Biogênese de Organelas , Paclitaxel/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND Idiopathic pulmonary fibrosis (IPF) can severely damage lung function, which may result in death. Emodin is a major ingredient of rhubarb and has been proven to protect against lung disruptions. Our study focused on the potential medicinal effect of emodin against IPF. MATERIAL AND METHODS The experiment subjects were fully-grown male Sprague-Dawley rats with average weight of 180-220 kg. Histological analyses, Western blotting analysis, quantitative real-time PCR, and statistical analysis were used in the study. RESULTS We found that emodin significantly reduced lung structural distortion, collagen overproduction, massive inflammatory cells infiltration, proinflammatory cytokines expansion, and injuries caused by administration of bleomycin (BLM). Additionally, emodin suppressed the accumulation of p-IκBα and NF-κB, while stimulating the Nrf2-antioxidant signaling process in damaged lungs. Emodin inhibited epithelial-mesenchymal transition (EMT) induced by BLM in the lungs. Moreover, emodin suppressed the TGF-ß1 expression and the downstream signal molecules p-Smad-2 and p-Smad-3, which are reinforced by BLM. Emodin can also reverse EMT-like shifts induced by recombinant TGF-ß1 in alveolar epithelial cultured cells. CONCLUSIONS The effect of emodin in fibrotic lung injury is closely related to its favorable properties of anti-inflammation and anti-oxidation.
Assuntos
Emodina/farmacologia , Fibrose Pulmonar Idiopática/tratamento farmacológico , Células A549/efeitos dos fármacos , Animais , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Bleomicina , Técnicas de Cultura de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Fibrose Pulmonar Idiopática/fisiopatologia , Inflamação/patologia , Pulmão/patologia , Masculino , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Inibidor de NF-kappaB alfa/efeitos dos fármacos , NF-kappa B/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fibrose Pulmonar/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/efeitos dos fármacosRESUMO
BACKGROUND: While patients affected by mild cognitive impairment (MCI) exhibit characteristic voxel-mirrored homotopic connectivity (VMHC) alterations, the ability of such VMHC abnormalities to predict the diagnosis of MCI in these patients remains uncertain. As such, this study was performed to evaluate the potential role of VMHC abnormalities in the diagnosis of MCI. METHODS: MCI patients and healthy controls (HCs) were enrolled and subjected to resting-state functional magnetic resonance imaging (rs-fMRI) and neuropsychological testing. VMHC and support vector machine (SVM) techniques were then used to examine the collected imaging data. RESULTS: Totally, 53 MCI patients and 68 healthy controls were recruited. Compared to HCs, MCI patients presented with an increase in postcentral gyrus VMHC. SVM classification demonstrated the ability of postcentral gyrus VMHC values to classify HCs and MCI patients with accuracy, sensitivity, and specificity values of 63.64 %, 71.69 %, and 89.71 %, respectively. CONCLUSION: VMHC abnormalities in the postcentral gyrus may be mechanistically involved in the pathophysiological progression of MCI patients, and these abnormal VMHC patterns may also offer utility as a neuroimaging biomarker for MCI patient diagnosis.
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Polysaccharides, the major active ingredient and quality control indicator of Polygomatum cyrtonema are in need of elucidation for its in vitro fermentation characteristics. This study aimed to investigate the structural characteristics of the homogeneous Polygomatum cyrtonema polysaccharide (PCP-80 %) and its effects on human intestinal bacteria and short chain fatty acids (SCFAs) production during the in vitro fermentation. The results revealed that PCP-80 % was yielded in 10.44 % and the molecular weight was identified to be 4.1 kDa. PCP-80 % exhibited a smooth, porous, irregular sheet structure and provided good thermal stability. The analysis of Gas chromatograph-mass spectrometer (GC-MS) suggested that PCP-80 % contained six glycosidic bonds, with 2,1-linked-Fruf residues accounted for a largest proportion. Nuclear magnetic resonance (NMR) provided additional evidence that the partial structure of PCP-80 % probably consists of â1)-ß-D-Fruf-(2 â as the main chain, accompanied by side chains dominated by â6)-ß-D-Fruf-(2â. Besides, PCP-80 % promoted the production of SCFAs and increased the relative abundance of beneficial bacteria such as Megamonas, Bifidobacterium and Phascolarctobacterium during in vitro colonic fermentation, which changed the composition of the intestinal microbiota. These findings indicated that Polygomatum cyrtonema polysaccharides were able to modulate the structure and composition of the intestinal bacteria flora and had potential probiotic properties.
Assuntos
Microbioma Gastrointestinal , Polygonatum , Humanos , Polygonatum/química , Fermentação , Polissacarídeos/química , Bactérias , Ácidos Graxos VoláteisRESUMO
Tomato (Solanum lycopersicum) fruits are derived from fertilized ovaries formed during flower development. Thus, fruit morphology is tightly linked to carpel number and identity. The SUPERMAN (SUP) gene is a key transcription repressor to define the stamen-carpel boundary and to control floral meristem determinacy. Despite SUP functions having been characterized in a few plant species, its functions have not yet been explored in tomato. In this study, we identified and characterized a fascinated and multi-locule fruit (fmf) mutant in Solanum pimpinellifolium background harboring a nonsense mutation in the coding sequence of a zinc finger gene orthologous to SUP. The fmf mutant produces supersex flowers containing increased numbers of stamens and carpels and sets malformed seedless fruits with complete flowers frequently formed on the distal end. fmf alleles in cultivated tomato background created by CRISPR-Cas9 showed similar floral and fruit phenotypes. Our results provide insight into the functional conservation and diversification of SUP members in different species. We also speculate the FMF gene may be a potential target for yield improvement in tomato by genetic engineering.
RESUMO
The effects of enzyme hydrolysis treatment, Aspergillus niger fermentation treatment, Trichoderma reesei fermentation treatment, Aspergillus niger-enzyme hydrolysis treatment and Trichoderma reesei-enzyme hydrolysis treatment on structural properties and adsorption capacities of soluble dietary fiber from Mesona chinensis Benth residues were evaluated and compared. The Aspergillus niger-enzyme hydrolysis treatment sample possessed more diverse structure, lower crystallinity and thermal stability than other modified samples. Meanwhile, it also observed the highest soluble dietary fiber yield (20.76 ± 0.31 %), water-holding capacity and glucose adsorption capacity (38.03 ± 0.28 mg/g). The Aspergillus niger fermentation treatment sample generated a high oil-holding capacity, nitrite ion adsorption capacity (181.84 ± 6.67 ug/g), cholesterol adsorption capacity (16.40 ± 0.37 mg/g) and sodium cholate adsorption capacity (94.80 ± 1.41 mg/g). Additionally, different monosaccharide composition was exhibited due to diverse extraction methods. Our finding revealed that these two modification methods could effectively enhance the economic value of Mesona chinensis Benth residues.
Assuntos
Celulase , Trichoderma , Aspergillus niger , Celulase/química , Adsorção , Fibras na Dieta , HidróliseRESUMO
The aim of this work was to prepare soluble dietary fibers (SDFs) from insoluble dietary fiber of navel orange peel (NOP-IDF) by mixed solid-state fermentation (M-SDF) and to investigate the influence of fermentation modification on the structural and functional characteristics of SDF in comparison with untreated soluble dietary fiber (U-SDF) of NOP-IDF. Based on this, the contribution of two kinds of SDF to the texture and microstructure of jelly was further examined. The analysis of scanning electron microscopy indicated that M-SDF exhibited a loose structure. The analysis of scanning electron microscopy indicated that M-SDF exhibited a loose structure. In addition, M-SDF exhibited increased molecular weight and elevated thermal stability, and had significantly higher relative crystallinity than U-SDF. Fermentation modified the monosaccharide composition and ratio of SDF, as compared to U-SDF. The above results pointed out that the mixed solid-state fermentation contributed to alteration of the SDF structure. Furthermore, the water holding capacity and oil holding capacity of M-SDF were 5.68 ± 0.36 g/g and 5.04 ± 0.04 g/g, which were about six times and two times of U-SDF, respectively. Notably, the cholesterol adsorption capacity of M-SDF was highest at pH 7.0 (12.88 ± 0.15 g/g) and simultaneously exhibited better glucose adsorption capacity. In addition, jellies containing M-SDF exhibited a higher hardness of 751.15 than U-SDF, as well as better gumminess and chewiness. At the same time, the jelly added with M-SDF performed a homogeneous porous mesh structure, which contributed to keeping the texture of the jelly. In general, M-SDF displayed much excellent structural and functional properties, which could be utilized to develop functional food.
RESUMO
Alkaline hydrogen peroxide (AHP), high-temperature cooking combined with ultrasonic (HTCU) and high-temperature cooking combined with complex enzyme hydrolysis (HTCE) were used to modify soluble dietary fiber (SDF) in Mesona chinensis Benth. residue (MCBR), then the structural and in vitro functional properties of A-SDF, HU-SDF and HE-SDF were investigated. Results showed that the three treatments significantly increased the yield of SDF. Scanning electron microscopy, FT-IR, monosaccharide composition, X-ray diffraction, molecular weight distribution and thermal stability analysis were employed to determine the structural changes. Compared with the control SDF (CK-SDF), HE-SDF and HU-SDF had looser and more porous microstructure, as well as lower crystallinity. In contrast to HE-SDF and HU-SDF, A-SDF exhibited a dense wavy microstructure, and elevated crystallinity and thermal stability. In addition, the monosaccharide composition and molecular weight of HU-SDF, HE-SDF and A-SDF were significantly altered as compared to CK-SDF. Moreover, the functional properties of HE-SDF and HU-SDF, including water holding capacity (WHC), oil holding capacity (OHC), glucose adsorption capacity (GAC), α-amylase activity inhibition ratio (α-AAIR), cholesterol adsorption capacity (CAC) and nitrite ion adsorption capacity (NIAC), were significantly higher than those of CK-SDF. However, the dense structure and high crystallinity of A-SDF resulted in a significantly lower GAC and NIAC than that of CK-SDF, with only WHC and α-AAIR being improved. Overall, this study showed that HTCU and HTCE could be used as ideal modification methods for MCBR SDF, HE-SDF and HU-SDF have potential as functional additives in food.
Assuntos
Fibras na Dieta , Lamiaceae , Fibras na Dieta/análise , Glucose , Peso Molecular , Monossacarídeos/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Água/químicaRESUMO
PURPOSE: The current study was undertaken to examine the anticancer potential of davanone against human ovarian cancer cells along with evaluating its effects on cell apoptosis, PI3K/AKT/MAPK signaling pathway and cell migration and invasion. METHODS: CCK-8 assay was performed for cell viability and clonogenic potential was examined through clonogenic assay. Acridine orange (AO)/Ethidium bromide (EB) dual staining assay was performed to detect apoptosis and quantification of apoptosis was achieved through annexin V-FITC/propidium iodide (PI) staining assay. Mitochondrial membrane potential (MMP) was studied via flow cytometric analysis of ovarian cancer cells. Cell migration and invasion potential of ovarian cancer cells was monitored via transwell assay. Western blotting technique was used to study PI3K/AKT/MAPK pathway. RESULTS: The results indicated that davanone induced dose as well as time dependent inhibition in cell viability of OVACAR-3 cells. Next, AO/EB staining suggested that the antiproliferative effects of davanone are apoptosis-mediated. There was a remarkable increase in apoptotic cell percentage with the molecule dose. Caspase-3, -8 and -9 activity along with Bax activity were observed to be increasing with davanone doses and Bcl-2 activity decreased with increasing molecule concentration. Transwell assay indicated potential inhibition of invasive and migratory ability of OVACAR-3 cells after davanone exposure. Finally, western blotting analysis revealed that davanone resulted in blocking of PI3K/AKT/MAPK signaling pathway in OVACAR-3 cells. CONCLUSION: The results indicate that davanone is a potential anticancer agent against human ovarian cancer mediated via caspase-dependent apoptosis, loss of MMP, inhibition of cell migration and invasion and targeting PI3K/AKT/MAPK signaling pathway.
Assuntos
Movimento Celular/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Neoplasias Ovarianas/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sesquiterpenos/farmacologia , Apoptose/efeitos dos fármacos , Feminino , Citometria de Fluxo , Humanos , Invasividade Neoplásica , Neoplasias Ovarianas/metabolismo , Transdução de SinaisRESUMO
Turbot can induce allergy in susceptible individuals due to the presence of parvalbumin (PV), a major fish allergen. This study aimed at evaluating the digestibility and the ability of PV to elicit the release of cellular degranulation, following treatment with tyrosinase (PV-Tyr), caffeic acid (PV-CA) and in combination (PV-Tyr/CA), using in vitro digestion and RBL-2H3 (passive rat basophil leukemia) cell line. The digestion assay products revealed that the stability of PV in simulated gastric fluid (SGF) was stronger, while in simulated intestinal fluid (SIF) was rather weak. Western blot analysis revealed that the IgG-binding abilities of the cross-linked PV were markedly reduced. Moreover, crosslinking hampered the release of cellular degranulation process in RBL-2H3 cell lines. PV-Tyr/CA showed highly significant reduction in the release rate of ß-hexosaminidase (66.02%), histamine (35.01%), tryptase (29.25%), cysteinyl leukotrienes (29.72%), prostaglandin D2 (34.96%), IL-4 (43.99%) and IL-13 (38.93%) and shown potential in developing hypoallergenic fish products.
Assuntos
Ácidos Cafeicos/química , Citocinas/metabolismo , Hipersensibilidade Alimentar/imunologia , Monofenol Mono-Oxigenase/química , Parvalbuminas/química , Alérgenos/química , Alérgenos/farmacocinética , Animais , Degranulação Celular/efeitos dos fármacos , Linhagem Celular , Digestão , Proteínas de Peixes da Dieta/química , Linguados , Suco Gástrico , Histamina/metabolismo , Humanos , Parvalbuminas/imunologia , Parvalbuminas/farmacologia , Ratos , beta-N-Acetil-Hexosaminidases/metabolismoRESUMO
The aim of this study was to analyze the effect of AAPH on the conformational structure and allergenicity of shrimp tropomyosin (TM). The structure of AAPH-TM was evaluated by SDS-PAGE, fluorescence, circular dichroism (CD) and ultraviolet light (UV), and the allergenicity was evaluated by in vivo and in vitro methods. Results showed that AAPH can induce structural changes through TM aggregations. These aggregations can decrease the IgG/IgE binding capacity on immunoblot analysis. Further competitive inhibition ELISA (ciELISA) results showed the IC50 of AAPH-TM (AAPH 0-25â¯mmol/l) changed from 0.086 to 46.2⯵g/ml, which correlated with TM structural changes. An RBL-2H3 cell assay showed that release rate of ß-hexosaminidase and histamine decreased by 51.6% and 68.1% with AAPH (5â¯mmol/l) treatment, respectively. A mouse model showed AAPH-TM could decrease levels of IgE/IgG1, release of histamine and mMCP-1 in sera. In conclusion, AAPH induced TM aggregation can cause structural changes and decrease the allergenicity.
Assuntos
Alérgenos/química , Alérgenos/imunologia , Amidinas/química , Penaeidae/química , Frutos do Mar/análise , Tropomiosina/química , Tropomiosina/imunologia , Animais , Imunoglobulina E/química , Camundongos , Penaeidae/imunologiaRESUMO
The aim of the present study was to evaluate Paralichthys olivaceus parvalbumin (PV) following treatment by laccase (LAC) in the presence of propyl gallate (PG) on the structure and potential allergenicity. The structure of LACâ¯+â¯PG treated PV was analyzed through SDS-PAGE, CD, fluorescence, and allergenicity was analyzed by immunological and cell model. Our results showed that LACâ¯+â¯PG treatment can induce structural changes through PV cross-linking. Western blotting and indirect ELISA analysis revealed the decrease in IgG binding capacity of PV, corresponding with the structural changes. The results of in vitro digestion illustrate that LACâ¯+â¯PG treated PV showed more resistance to gastrointestinal digestion compared to untreated PV. The release rate of ß-hexosaminidase and histamine decreased by 35.6% and 66.9%, respectively, with LACâ¯+â¯PG treatment by RBL-2H3 cell assay. Considering the wide utilization of LAC in food industry, our treatment reveals its potential for creation of hypoallergenic fish products under mild reaction conditions.
Assuntos
Alérgenos/imunologia , Proteínas de Peixes/imunologia , Linguados/imunologia , Lacase/metabolismo , Parvalbuminas/imunologia , Galato de Propila/química , Animais , Catálise , Reagentes de Ligações Cruzadas/química , Digestão , Ensaio de Imunoadsorção Enzimática , Proteínas de Peixes/química , Indústria Alimentícia , Histamina/metabolismo , Parvalbuminas/química , beta-N-Acetil-Hexosaminidases/metabolismoRESUMO
The present study investigated the anti-arthritic effects of methionine in neonatal rats. Rats were divided into four groups, with six rats in each group. The rats were administered methionine (150- or 300-mg/kg body weight) orally for 45 consecutive days. The expression levels of catalase, superoxide dismutase (SOD), reduced glutathione (GSH), lipid peroxidation, glutathione peroxidase (Gpx), prostaglandin E2 (PGE2), matrix metalloproteinase-3, uric acid, nitric oxide (NO), ceruloplasmin, inducible nitric oxide synthase (iNOS), and nuclear factor (NF)-κB were determined in rheumatoid arthritis-induced neonatal rats. The levels of SOD, catalase, Gpx, and GSH were substantially reduced in control rats, while the levels of other parameters were increased in control neonatal rats. However, methionine supplementation significantly increased (more than 40%) the levels of SOD, catalase, Gpx, and GSH in neonatal rats. The levels of lipid peroxidation, uric acid, ceruloplasmin, NO, and PGE2 were significantly reduced following methionine supplementation. Furthermore, NF-κB mRNA expression was substantially reduced up to 51.7% in the 300-mg/kg methionine group, whereas the mRNA expression of iNOS was reduced up to 43.5% in the 300-mg/kg methionine group. NF-κB protein expression was substantially reduced up to 45.8% in the 300-mg/kg methionine group, whereas the protein expression of iNOS was reduced up to 45.4% in the 300-mg/kg methionine group. Taken together, these data suggest that methionine supplementation was effective against rheumatoid arthritis.
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Advanced glycation endproducts (AGEs) are the harmful products of non-enzymatic reactions in foods formed during the heating process. In order to reduce the content of AGEs in foods, the inhibitory effect of different proportions of transglutaminase (TGase) and chitosan oligosaccharides (COS) on the AGEs of seabream fish meat sausage was studied. The results indicated that the TGase/COS ratio of 1 : 1 could inhibit the formation of AGEs, showing especially a decreased Nε-carboxymethyl-lysine (CML) content and a twice higher inhibition rate (36.4%) than that by aminoguanidine (17.4%), a commonly effective positive inhibitor of AGEs. The data of lysine, fructosamine, and glucosamine contents, combined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses, demonstrated that cross-linking of proteins and glycosylation of glutamine induced by TGase and COS resulted in steric hindrance that inhibited glycation. These findings revealed that TGase catalyzed glycosylation with COS differently from general antioxidants had potential as an effective treatment to inhibit the formation of AGEs in fishery products.
Assuntos
Produtos Finais de Glicação Avançada/química , Produtos da Carne/análise , Oligossacarídeos/química , Transglutaminases/química , Animais , Biocatálise , Quitosana/química , Manipulação de Alimentos , Glicosilação , Espectrometria de Massas , Dourada , Alimentos Marinhos/análiseRESUMO
ß-Lactoglobulin (ß-LG) is recognized as the major milk allergen. In this study, the effects of transglutaminase (TGase) and glucosamine (GlcN)-catalyzed glycosylation and glycation on the conformational structure and allergenicity of ß-LG were investigated. The formations of cross-linked peptides were demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and GlcN-conjugated modification was identified using matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS). Structural analysis revealed that glycosylation and glycation of ß-LG induced unfolding of the primary protein structure followed by a loss of the secondary structure. As revealed by circular dichroism (CD) spectroscopy, glycosylated ß-LG exhibited the highest increase in the ß-sheets from 32.6% to 40.4% (25 °C) and 44.2% (37 °C), and the percentage of α-helices decreased from 17.7% to 14.4% (25 °C) and 12.3% (37 °C), respectively. The tertiary and quaternary structures of ß-LG also changed significantly during glycosylation and glycation, along with reduced free amino groups and variation in surface hydrophobicity. Immunoblotting and indirect enzyme-linked immuno sorbent assay (ELISA) analyses demonstrated that the lowest IgG- and IgE-binding capacities of ß-LG were obtained following glycosylation at 37 °C, which were 52.7% and 56.3% lower than that of the native protein, respectively. The reduction in the antigenicity and potential allergenicity of glycosylated ß-LG was more pronounced compared to TGase treated- and glycated ß-LG, which correlated well with the structural changes. These results suggest that TGase-catalyzed glycosylation has more potential compared to glycation for mitigating the allergenic potential of milk products.