The Experts below are selected from a list of 1860 Experts worldwide ranked by ideXlab platform
Harry Gruppen - One of the best experts on this subject based on the ideXlab platform.
-
legumin allergens from peanuts and soybeans effects of denaturation and aggregation on allergenicity
Molecular Nutrition & Food Research, 2008Co-Authors: Evelien L Van Boxtel, Lambertus A M Van Den Broek, Stef J Koppelman, Harry GruppenAbstract:Legumin proteins Ara h 3 from peanuts and Glycinin from soybeans are increasingly described as important allergens. The stability of an allergen's IgE binding capacity towards heating and digestion is considered an important characteristic for food allergens. We investigated the effects of heating and digestion on the IgE binding of Ara h 3 and Glycinin. Both proteins are relatively stable to denaturation, having denaturation temperatures ranging from 70 to 92°C, depending on their quaternary structure and the ionic strength. Aggregates were formed upon heating, which were partly soluble for Glycinin. Heating slightly decreased the pepsin digestion rate of both allergens. However, heating did not affect the IgE binding capacity of the hydrolyzates, as after only 10 min of hydrolysis no IgE binding could be detected any more in all samples. Peanut allergen Ara h 1, when digested under equal conditions, still showed IgE binding after 2 h of hydrolysis. Our results indicate that the IgE binding capacity of legumin allergens from peanuts and soybeans does not withstand peptic digestion. Consequently, these allergens are likely unable to sensitize via the gastro-intestinal tract and cause systemic food allergy symptoms. These proteins might thus be less important allergens than was previously assumed. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.
-
identification of strong aggregating regions in soy Glycinin upon enzymatic hydrolysis
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Bas J H Kuipers, Harry GruppenAbstract:Upon hydrolysis with chymotrypsin, soy Glycinin has a strong tendency to aggregate. The regions of Glycinin from which the aggregating peptides originate were identified by accumulative-quantitative peptide mapping. To this end, the aggregating peptides were further hydrolyzed with trypsin to obtain peptides of which the sequence can be identified using RP-HPLC-MS/MS. This resulted in a hydrolysate in which 90% of the proteinaceous material was dissolved. The soluble fraction was analyzed using the method of accumulative-quantitative peptide mapping: fractionation using ion exchange chromatography, followed by identification of peptides by RP-HPLC-MS/MS, quantification based on the absorbance at 214 nm, and finally peptide mapping. For the peptide mapping the proportions in which each of the five Glycinin subunits are present, as determined by Edman degradation, were taken into account. The results showed that mainly the basic polypeptide and a part of the acidic polypeptide, close to the location of the disulfide bridge between the basic and acidic polypeptides, are present in the aggregating peptide fraction. On the basis of the results obtained, an aggregation mechanism was proposed. The hydrophilic acidic polypeptides shield the hydrophobic basic polypeptides, and the former are preferentially degraded upon hydrolysis. This results in a net increase in hydrophobicity of the remaining material, which mainly consists of the basic polypeptide fragments. This increase in hydrophobicity is proposed to be the driving force in the aggregation of chymotrypsin-derived peptides of Glycinin.
-
comparison of the aggregation behavior of soy and bovine whey protein hydrolysates
Biotechnology Advances, 2007Co-Authors: Bas J H Kuipers, Arno C Alting, Harry GruppenAbstract:Abstract Soy-derived proteins (soy protein isolate, Glycinin, and β-conGlycinin) and bovine whey-derived proteins (whey protein isolate, α-lactalbumin, β-lactoglobulin) were hydrolyzed using subtilisin Carlsberg, chymotrypsin, trypsin, bromelain, and papain. The (in)solubility of the hydrolysates obtained was studied as a function of pH. At neutral pH, all soy-derived protein hydrolysates, particularly those from Glycinin, obtained by hydrolysis with subtilisin Carlsberg, chymotrypsin, bromelain, and papain showed a stronger aggregation compared to the non-hydrolyzed ones. This increase in aggregation was not observed upon hydrolysis by trypsin. None of the whey-derived protein hydrolysates exhibited an increase in aggregation at neutral pH. The high abundance of theoretical cleavage sites in the hydrophobic regions of Glycinin probably explains the stronger exposure of hydrophobic groups than for the other proteins, which is suggested to be the driving force in the aggregate formation.
-
micrometer sized fibrillar protein aggregates from soy Glycinin and soy protein isolate
Journal of Agricultural and Food Chemistry, 2007Co-Authors: C Akkermans, Harry Gruppen, A J Van Der Goot, P Venema, J M Vereijken, E Van Der Linden, R M BoomAbstract:Long, fibrillar semiflexible aggregates were formed from soy Glycinin and soy protein isolate (SPI) when heated at 85 °C and pH 2. Transmission electron microscopy analysis showed that the contour length of the fibrils was ∼1 µm, the persistence length 2.3 µm, and the thickness a few nanometers. Fibrils formed from SPI were more branched than the fibrils of soy Glycinin. Binding of the fluorescent dye Thioflavin T to the fibrils showed that β-sheets were present in the fibrils. The presence of the fibrils resulted in an increase in viscosity and shear thinning behavior. Flow-induced birefringence measurements showed that the behavior of the fibrils under flow can be described by scaling relations derived for rodlike macromolecules. The fibril formation could be influenced by the protein concentration and heating time. Most properties of soy Glycinin fibrils are comparable to β-lactoglobulin fibrils.
-
research review paper comparison of the aggregation behavior of soy and bovine whey protein hydrolysates
2007Co-Authors: Arno C Alting, Harry GruppenAbstract:Soy-derived proteins (soy protein isolate, Glycinin, and β-conGlycinin) and bovine whey-derived proteins (whey protein isolate, α-lactalbumin, β-lactoglobulin) were hydrolyzed using subtilisin Carlsberg, chymotrypsin, trypsin, bromelain, and papain. The (in) solubility of the hydrolysates obtained was studied as a function of pH. At neutral pH, all soy-derived protein hydrolysates, particularly those from Glycinin, obtained by hydrolysis with subtilisin Carlsberg, chymotrypsin, bromelain, and papain showed a stronger aggregation compared to the non-hydrolyzed ones. This increase in aggregation was not observed upon hydrolysis by trypsin. None of the whey-derived protein hydrolysates exhibited an increase in aggregation at neutral pH. The high abundance of theoretical cleavage sites in the hydrophobic regions of Glycinin probably explains the stronger exposure of hydrophobic groups than for the other proteins, which is suggested to be the driving force in the aggregate formation.
Yao Wang - One of the best experts on this subject based on the ideXlab platform.
-
rapid and sensitive detection of the food allergen Glycinin in powdered milk using a lateral flow colloidal gold immunoassay strip test
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Yao Wang, Ruiguang Deng, Gaiping Zhang, Qingmei Li, Zhixi Li, Jifei Yang, Xiaofei HuAbstract:A rapid immunochromatographic lateral flow test strip in a sandwich format was developed with the colloidal gold-labeled mouse antiGlycinin monoclonal antibody (mAb) and rabbit antiGlycinin polyclonal antibody (pAb) to specifically identify Glycinin, a soybean allergen. The test strip is composed of a sample pad, a conjugate reagent pad, an absorbent pad, and a test membrane containing a control line and a test line. This test strip has high sensitivity, and results can be obtained within 10 min without sophisticated procedures. The limit of detection (LOD) of the test strip was calculated to be 0.69 mg/kg using an optical density scanner that measures relative optical density. The assay showed high specificity for Glycinin, with no cross-reactions with other soybean proteins or other food allergens. The recoveries of the lateral flow test strip in detecting Glycinin in powdered milk samples ranged between 80.5 and 89.9% with relative standard deviations of less than 5.29% (intra-assay) and 6.72% (interas...
-
rapid and sensitive detection of the food allergen Glycinin in powdered milk using a lateral flow colloidal gold immunoassay strip test
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Yao Wang, Ruiguang Deng, Gaiping Zhang, Jifei Yang, Yaning SunAbstract:A rapid immunochromatographic lateral flow test strip in a sandwich format was developed with the colloidal gold-labeled mouse antiGlycinin monoclonal antibody (mAb) and rabbit antiGlycinin polyclonal antibody (pAb) to specifically identify Glycinin, a soybean allergen. The test strip is composed of a sample pad, a conjugate reagent pad, an absorbent pad, and a test membrane containing a control line and a test line. This test strip has high sensitivity, and results can be obtained within 10 min without sophisticated procedures. The limit of detection (LOD) of the test strip was calculated to be 0.69 mg/kg using an optical density scanner that measures relative optical density. The assay showed high specificity for Glycinin, with no cross-reactions with other soybean proteins or other food allergens. The recoveries of the lateral flow test strip in detecting Glycinin in powdered milk samples ranged between 80.5 and 89.9% with relative standard deviations of less than 5.29% (intra-assay) and 6.72% (interassay). Therefore, the test strip is useful as a quantitative, semiquantitative, or qualitative detection method for Glycinin in powdered milk. In addition, the test strip can be used to detect Glycinin in other processed foods and may be a valuable tool in identifying effective approaches for reducing the impact of Glycinin.
Qin Wang - One of the best experts on this subject based on the ideXlab platform.
-
ionic strength and ph responsive permeability of soy Glycinin microcapsules
Langmuir, 2018Co-Authors: Nannan Chen, Jinglin Zhang, Lei Mei, Qin WangAbstract:Recently, hollow protein microcapsules have been made simply by heating the microphase separated soy Glycinin microdomains. However, the properties (e.g., mechanical properties and permeability) that relate to the application of these microcapsules are unknown. In this study, the permeability of the soy Glycinin microcapsules was investigated by confocal laser scanning microscopy (CLSM), as influenced by ionic strength and pH using fluorescein isothiocyanate-dextran (FITC-dextran). The Glycinin microcapsules kept the integrity between pH 1 and 11.5, swelled when pH was below 3 or above pH 11, dissociated at pH above 11.5 and deswelled slightly at pH 1. When the pH increased above 11, the permeability of the microcapsule significantly increased. Remarkably, when the pH was below the isoelectric point of Glycinin (≈pH 5), FITC-dextran spontaneously accumulated inside the microcapsule with a significantly higher concentration than that in bulk solution, as evidenced by the strong intensity increase of fluore...
-
Ionic Strength and pH Responsive Permeability of Soy Glycinin Microcapsules
2018Co-Authors: Nannan Chen, Jinglin Zhang, Lei Mei, Qin WangAbstract:Recently, hollow protein microcapsules have been made simply by heating the microphase separated soy Glycinin microdomains. However, the properties (e.g., mechanical properties and permeability) that relate to the application of these microcapsules are unknown. In this study, the permeability of the soy Glycinin microcapsules was investigated by confocal laser scanning microscopy (CLSM), as influenced by ionic strength and pH using fluorescein isothiocyanate-dextran (FITC-dextran). The Glycinin microcapsules kept the integrity between pH 1 and 11.5, swelled when pH was below 3 or above pH 11, dissociated at pH above 11.5 and deswelled slightly at pH 1. When the pH increased above 11, the permeability of the microcapsule significantly increased. Remarkably, when the pH was below the isoelectric point of Glycinin (≈pH 5), FITC-dextran spontaneously accumulated inside the microcapsule with a significantly higher concentration than that in bulk solution, as evidenced by the strong intensity increase of fluorescence. This unique feature significantly increased the loading amount of FITC-dextran. The permeability of microcapsules was also increased by adding salt but less significant than by adjusting pH. The surface of the microcapsules became coarser when the permeability increased, which was revealed by scanning electron microscopy. These results show that soy Glycinin has a great potential to be used as a wall material to fabricate hollow microcapsules that could find applications in biomedicine and food industry
Nannan Chen - One of the best experts on this subject based on the ideXlab platform.
-
resolving the mechanisms of soy Glycinin self coacervation and hollow condensate formation
ACS Macro Letters, 2020Co-Authors: Nannan Chen, Ziliang Zhao, Yong Wang, Rumiana DimovaAbstract:Self-coacervation of animal-derived proteins has been extensively investigated while that of plant proteins remains largely unexplored. Here, we study the process of soy Glycinin self-coacervation ...
-
ionic strength and ph responsive permeability of soy Glycinin microcapsules
Langmuir, 2018Co-Authors: Nannan Chen, Jinglin Zhang, Lei Mei, Qin WangAbstract:Recently, hollow protein microcapsules have been made simply by heating the microphase separated soy Glycinin microdomains. However, the properties (e.g., mechanical properties and permeability) that relate to the application of these microcapsules are unknown. In this study, the permeability of the soy Glycinin microcapsules was investigated by confocal laser scanning microscopy (CLSM), as influenced by ionic strength and pH using fluorescein isothiocyanate-dextran (FITC-dextran). The Glycinin microcapsules kept the integrity between pH 1 and 11.5, swelled when pH was below 3 or above pH 11, dissociated at pH above 11.5 and deswelled slightly at pH 1. When the pH increased above 11, the permeability of the microcapsule significantly increased. Remarkably, when the pH was below the isoelectric point of Glycinin (≈pH 5), FITC-dextran spontaneously accumulated inside the microcapsule with a significantly higher concentration than that in bulk solution, as evidenced by the strong intensity increase of fluore...
-
Ionic Strength and pH Responsive Permeability of Soy Glycinin Microcapsules
2018Co-Authors: Nannan Chen, Jinglin Zhang, Lei Mei, Qin WangAbstract:Recently, hollow protein microcapsules have been made simply by heating the microphase separated soy Glycinin microdomains. However, the properties (e.g., mechanical properties and permeability) that relate to the application of these microcapsules are unknown. In this study, the permeability of the soy Glycinin microcapsules was investigated by confocal laser scanning microscopy (CLSM), as influenced by ionic strength and pH using fluorescein isothiocyanate-dextran (FITC-dextran). The Glycinin microcapsules kept the integrity between pH 1 and 11.5, swelled when pH was below 3 or above pH 11, dissociated at pH above 11.5 and deswelled slightly at pH 1. When the pH increased above 11, the permeability of the microcapsule significantly increased. Remarkably, when the pH was below the isoelectric point of Glycinin (≈pH 5), FITC-dextran spontaneously accumulated inside the microcapsule with a significantly higher concentration than that in bulk solution, as evidenced by the strong intensity increase of fluorescence. This unique feature significantly increased the loading amount of FITC-dextran. The permeability of microcapsules was also increased by adding salt but less significant than by adjusting pH. The surface of the microcapsules became coarser when the permeability increased, which was revealed by scanning electron microscopy. These results show that soy Glycinin has a great potential to be used as a wall material to fabricate hollow microcapsules that could find applications in biomedicine and food industry
Yaning Sun - One of the best experts on this subject based on the ideXlab platform.
-
rapid and sensitive detection of the food allergen Glycinin in powdered milk using a lateral flow colloidal gold immunoassay strip test
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Yao Wang, Ruiguang Deng, Gaiping Zhang, Jifei Yang, Yaning SunAbstract:A rapid immunochromatographic lateral flow test strip in a sandwich format was developed with the colloidal gold-labeled mouse antiGlycinin monoclonal antibody (mAb) and rabbit antiGlycinin polyclonal antibody (pAb) to specifically identify Glycinin, a soybean allergen. The test strip is composed of a sample pad, a conjugate reagent pad, an absorbent pad, and a test membrane containing a control line and a test line. This test strip has high sensitivity, and results can be obtained within 10 min without sophisticated procedures. The limit of detection (LOD) of the test strip was calculated to be 0.69 mg/kg using an optical density scanner that measures relative optical density. The assay showed high specificity for Glycinin, with no cross-reactions with other soybean proteins or other food allergens. The recoveries of the lateral flow test strip in detecting Glycinin in powdered milk samples ranged between 80.5 and 89.9% with relative standard deviations of less than 5.29% (intra-assay) and 6.72% (interassay). Therefore, the test strip is useful as a quantitative, semiquantitative, or qualitative detection method for Glycinin in powdered milk. In addition, the test strip can be used to detect Glycinin in other processed foods and may be a valuable tool in identifying effective approaches for reducing the impact of Glycinin.