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1.
Clin Nutr ; 40(11): 5655-5658, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34666256

RESUMO

BACKGROUND & AIMS: Donor human milk (DHM) is recommended as the first alternative for preterm infants if their mother's own milk is not available or if the quantity is not sufficient. The most commonly used technique to eliminate microbial contaminants in DHM is holder pasteurization (HoP). However, the heating process during HoP partially destroys milk bioactive factors such as insulin. Therefore, innovative techniques have been developed as alternatives to HoP. The objective of this study was to determine the effect of HoP, high-temperature-short-time (HTST), thermoultrasonication (TUS), ultraviolet-C irradiation (UV-C), and high-pressure processing (HPP) on the insulin concentration in DHM. METHODS: Milk samples from 28 non-diabetic mothers were collected. The milk samples were aliquoted and either left untreated or treated with HoP (62.5 °C; 30 min), HTST (72 °C; 15 s), TUS (60 W; 6 min), UV-C (4863 J/L), or HPP (500 MPa; 5 min). RESULTS: The mean insulin concentration in untreated milk was 79 ± 41 pmol/L. The mean insulin retention rate was 67% for HoP, 78% for HTST, 97% for TUS, 94% for UV-C, and 106% for HPP. The mean insulin concentration in milk treated with HoP was significantly lower compared to untreated milk (p = 0.01). CONCLUSION: TUS, UV-C, and HPP preserve insulin in DHM. The insulin concentration in DHM is affected to a larger extent by HoP than by HTST. These results indicate that TUS, UV-C, and HPP may serve as alternatives to HoP.

2.
PLoS One ; 16(8): e0256435, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34411191

RESUMO

BACKGROUND: Provision of donor human milk is handled by established human milk banks that implement all required measures to ensure its safety and quality. Detailed human milk banking guidelines on a European level are currently lacking, while the information available on the actual practices followed by the European human milk banks, remains limited. The aim of this study was to collect detailed data on the actual milk banking practices across Europe with particular emphasis on the practices affecting the safety and quality of donor human milk. MATERIALS AND METHODS: A web-based questionnaire was developed by the European Milk Bank Association (EMBA) Survey Group, for distribution to the European human milk banks. The questionnaire included 35 questions covering every step from donor recruitment to provision of donor human milk to each recipient. To assess the variation in practices, all responses were then analyzed for each country individually and for all human milk banks together. RESULTS: A total of 123 human milk banks completed the questionnaire, representing 85% of the European countries that have a milk bank. Both inter- and intra-country variation was documented for most milk banking practices. The highest variability was observed in pasteurization practices, storage and milk screening, both pre- and post-pasteurization. CONCLUSION: We show that there is a wide variability in milk banking practices across Europe, including practices that could further improve the efficacy of donor human milk banking. The findings of this study could serve as a tool for a global discussion on the efficacy and development of additional evidence-based guidelines that could further improve those practices.

3.
Ultrason Sonochem ; 77: 105668, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34298307

RESUMO

To extend the shelf life and retain bioactive proteins in milk, this study utilized microfiltration (MF) combined with ultrasonication to treat skim milk and investigated its efficiency in removing bacteria and retaining bioactive proteins compared with HTST pasteurization and microfiltration alone. Results showed that microfiltration combined with ultrasonication at 1296 J/mL could completely remove the bacteria in skim milk. Ultrasonication further extended the shelf life (4 °C) of microfiltered skim milk, which could reach at least 40 days when MF was combined with ˃1296 J/mL ultrasonication. In addition, ELISA showed that HTST pasteurization significantly decreased the levels of IgG by ~30%, IgA by ~ 50%, IgM by ~60%, and lactoferrin by ~40%, whereas the activity of the enzymes lactoperoxidase and xanthine oxidase were also decreased by ~ 20%. Compared with HTST, MF alone or combined with ultrasonication retained these bioactive proteins to a larger degree. On the other hand, proteomics indicated both damage to casein micelle and fat globule structures in milk when ultrasonication at >1296 J/mL was applied, as shown by increases in caseins and milk fat globular proteins. Simultaneously, this ultrasound intensity also decreased levels of bioactive proteins, such as complement factors. Taken together, this study provided new insights that may help to implement this novel combination of non-thermal technologies for the dairy industry aimed at improving milk quality and functionality.


Assuntos
Filtração , Armazenamento de Alimentos , Leite/química , Proteínas/química , Sonicação , Animais , Temperatura
4.
Nutrients ; 13(5)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068142

RESUMO

BACKGROUND: Since the outbreak of coronavirus disease 2019 (COVID-19), many put their hopes in the rapid availability of effective immunizations. Human milk, containing antibodies against syndrome coronavirus 2 (SARS-CoV-2), may serve as means of protection through passive immunization. We aimed to determine the presence and pseudovirus neutralization capacity of SARS-CoV-2 specific IgA in human milk of mothers who recovered from COVID-19, and the effect of pasteurization on these antibodies. METHODS: This prospective case control study included lactating mothers, recovered from (suspected) COVID-19 and healthy controls. Human milk and serum samples were collected. To assess the presence of SARS-CoV-2 antibodies we used multiple complementary assays, namely ELISA with the SARS-CoV-2 spike protein (specific for IgA and IgG), receptor binding domain (RBD) and nucleocapsid (N) protein for IgG in serum, and bridging ELISA with the SARS-CoV-2 RBD and N protein for specific Ig (IgG, IgM and IgA in human milk and serum). To assess the effect of pasteurization, human milk was exposed to Holder (HoP) and High Pressure Pasteurization (HPP). RESULTS: Human milk contained abundant SARS-CoV-2 antibodies in 83% of the proven cases and in 67% of the suspected cases. Unpasteurized milk with and without these antibodies was found to be capable of neutralizing a pseudovirus of SARS-CoV-2 in (97% and 85% of the samples respectively). After pasteurization, total IgA antibody levels were affected by HoP, while SARS-CoV-2 specific antibody levels were affected by HPP. Pseudovirus neutralizing capacity of the human milk samples was only retained with the HPP approach. No correlation was observed between milk antibody levels and neutralization capacity. CONCLUSIONS: Human milk from recovered COVID-19-infected mothers contains SARS-CoV-2 specific antibodies which maintained neutralization capacity after HPP. All together this may represent a safe and effective immunization strategy after HPP.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Lactação , Leite Humano/imunologia , Pasteurização , SARS-CoV-2/imunologia , Adulto , Feminino , Humanos
5.
Adv Nutr ; 12(4): 1100-1107, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-33857283

RESUMO

Infants are vulnerable consumers and highly depend on dietary proteins for growth and development during their first months of life. Infant formula (IF) and follow-on formula (FOF) have been developed to meet these requirements, although few protein sources are currently allowed to be used. At the same time, allergies to these available protein sources are becoming more frequent. There is thus a need to explore alternative protein sources for infant nutrition. One alternative could be quinoa, which is a pseudocereal that is naturally free from gluten and has a high protein content and quality. This review assessed the composition, nutritional properties, and applicability of quinoa proteins for IF and FOF as well as the legal framework for their use in the European Union (EU). The protein quality of isolated quinoa proteins (IQPs) is relatively high compared with other plant-based proteins like rice. Besides, during the protein isolation process, unfavorable compounds are mostly removed, ensuring that the final product can comply with the maximum residue concentrations allowed. Overall, IF and FOF are strictly regulated under the Foods for Specific Groups (FSG) Regulation (EU) No 609/2013 and more research is needed before the introduction of IQP in such products is considered, but this review shows it has several promising features that warrant further investigation.


Assuntos
Chenopodium quinoa , Fórmulas Infantis/normas , Valor Nutritivo , Proteínas na Dieta , União Europeia , Glutens , Humanos , Lactente
6.
Mol Nutr Food Res ; 65(8): e2000834, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33559978

RESUMO

SCOPE: ß-lactoglobulin (BLG) is a major cow milk allergen encountered by the immune system of infants fed with milk-based formulas. To determine the effect of processing on immunogenicity of BLG, this article characterized how heated and glycated BLG are recognized and internalized by APCs. Also, the effect of heat-induced structural changes as well as gastrointestinal digestion on immunogenicity of BLG is evaluated. METHODS AND RESULTS: The binding and uptake of BLG from raw cow milk and heated either alone (BLG-H) or with lactose/glucose (BLG-Lac and BLG-Glu) to the receptors present on APCs are analyzed by ELISA and cell-binding assays. Heated and glycated BLG is internalized via galectin-3 (Gal-3)and scavenger receptors (CD36 and SR-AI) while binding to the receptor for advanced glycation end products (R AGE) does not cause internalization. Receptor affinity of BLG is dependent on increased hydrophobicity, ß-sheet exposure and aggregation. Digested glycated BLG maintained binding to sRAGE and Gal-3 but not to CD36 and SR-AI, and is detected on the surface of APCs. This suggests a mechanism via which digested glycated BLG may trigger innate (via RAGE) and adaptive immunity (via Gal-3). CONCLUSIONS: This study defines structural characteristics of heated and glycated BLG determining its interaction with APCs via specific receptors thus revealing enhanced immunogenicity of glycated versus heated BLG.

7.
Food Chem ; 337: 127973, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32927224

RESUMO

To establish the effect of the presence of milk serum proteins on heat-induced changes to lactoferrin, lactoferrin alone, and lactoferrin mixed with either milk serum or ß-lactoglobulin was heated at 65 °C, 70 °C and 75 °C for 30 min. After heating, the effect of milk serum proteins on aggregation of lactoferrin was characterized, after which the effect of such aggregation on digestion and bacteriostatic capacity of lactoferrin were determined. The presence of milk serum proteins accelerated the aggregation of lactoferrin during heating through thiol/disulphide interchange. Lactoferrin also formed disulphide-linked aggregates when it was heated with ß-lactoglobulin. Protein aggregates formed at 75 °C were much more resistant to infant digestion, causing decreased peptide release from lactoferrin. Heating lactoferrin and milk serum proteins together accelerated the loss of bacteriostatic activity upon heating. In conclusion, heat-induced aggregation of lactoferrin with milk serum proteins affected both its digestion and its bacteriostatic activity.


Assuntos
Lactoferrina/química , Lactoferrina/farmacocinética , Proteínas do Leite/química , Animais , Antibacterianos/farmacologia , Digestão , Suco Gástrico , Temperatura Alta , Humanos , Lactoglobulinas/química , Leite/química , Tamanho da Partícula , Proteínas do Soro do Leite/química
8.
Nutrients ; 12(12)2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33333859

RESUMO

Immune-globulin E (IgE)-mediated food allergy is characterized by a variety of clinical entities within the gastrointestinal tract, skin and lungs, and systemically as anaphylaxis. The default response to food antigens, which is antigen specific immune tolerance, requires exposure to the antigen and is already initiated during pregnancy. After birth, tolerance is mostly acquired in the gut after oral ingestion of dietary proteins, whilst exposure to these same proteins via the skin, especially when it is inflamed and has a disrupted barrier, can lead to allergic sensitization. The crosstalk between the skin and the gut, which is involved in the induction of food allergy, is still incompletely understood. In this review, we will focus on mechanisms underlying allergic sensitization (to food antigens) via the skin, leading to gastrointestinal inflammation, and the development of IgE-mediated food allergy. Better understanding of these processes will eventually help to develop new preventive and therapeutic strategies in children.


Assuntos
Alérgenos/imunologia , Dessensibilização Imunológica/métodos , Hipersensibilidade Alimentar/imunologia , Trato Gastrointestinal/imunologia , Pele/imunologia , Reações Cruzadas/imunologia , Alimentos/efeitos adversos , Humanos , Imunoglobulina E/imunologia
9.
Front Nutr ; 7: 162, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117838

RESUMO

This study provided insights into the degradation of human milk proteins in an in vitro infant digestion model by comparing colostrum (week 1) and mature milk (week 4) of 7 Chinese mothers individually. In this study, we adapted the exiting INFOGEST in vitro model, to conditions representative to infants (0 to 3 month-old). The level of undigested proteins was analyzed by LC-MS/MS after gel-electrophoretic separation and in-gel digestion. The BCA protein assay showed that the total undigested milk protein content decreased from the start to the end of digestion with variations between mothers, especially in the gastric phase (25-80%). Undigested proteins could also still be found after the intestinal phase, ranging from 0.5 to 4.2% of initial protein content. Based on LC-MS/MS analysis, milk protein digestion varied between the mothers individually, especially during the gastric phase. No differences could be observed between protein digestion from colostrum and mature milk after the intestinal phase. The highest levels of proteins remaining after intestinal digestion can be linked to the group immune-active proteins, for all mothers. The level of protease inhibitors and total protein content in the milk did not correlate with the overall proteolysis during digestion. The results also showed that milk serum proteins partly remained after the gastric phase, with 33% remaining from colostrum and 37% remaining from mature milk. More than 40 milk serum proteins were detected after the intestinal phase. Some of the highly abundant milk serum proteins (lactoferrin, serum albumin, bile salt-activated lipase, immunoglobulins, α1-antichymotrypsin) were still partially present intact after the intestinal phase, for all mothers. Caseins were also not completely digested in the gastric phase, with 35% remaining from colostrum and 13% remaining from mature milk. Caseins, on the other hand, were almost completely digested after the intestinal phase. The complete degradation of caseins into peptides might be related to their structural features. Overall, this study showed that digestion differed for the various human milk proteins by adapting an in vitro digestion model to infant physiological conditions, with the main differences between digestion of the milk from individual mothers being observed after gastric digestion.

10.
Nutrients ; 12(8)2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32824739

RESUMO

Dry heating of cow's milk protein, as applied in the production of "baked milk", facilitates the resolution of cow's milk allergy symptoms upon digestion. The heating and glycation-induced changes of the protein structure can affect both digestibility and immunoreactivity. The immunological consequences may be due to changes in the peptide profile of the digested dry heated milk protein. Therefore, cow's milk protein powder was heated at low temperature (60 °C) and high temperature (130 °C) and applied to simulated infant in vitro digestion. Digestion-derived peptides after 10 min and 60 min in the intestinal phase were measured using LC-MS/MS. Moreover, digests after 10 min intestinal digestion were applied to a Caco-2 cell monolayer. T-cell epitopes were analysed using prediction software, while specific immunoglobin E (sIgE) binding epitopes were identified based on the existing literature. The largest number of sIgE binding epitopes was found in unheated samples, while T-cell epitopes were equally represented in all samples. Transport of glycated peptide indicated a preference for glucosyl lysine and lactosyl-lysine-modified peptides, while transport of peptides containing epitope structures was limited. This showed that the release of immunoreactive peptides can be affected by the applied heating conditions; however, availability of peptides containing epitopes might be limited.


Assuntos
Células CACO-2/metabolismo , Digestão/fisiologia , Manipulação de Alimentos/métodos , Temperatura Alta , Fenômenos Fisiológicos da Nutrição do Lactente/fisiologia , Intestinos/fisiologia , Hipersensibilidade a Leite/prevenção & controle , Proteínas do Leite/metabolismo , Leite , Peptídeos/metabolismo , Transporte Proteico , Proteólise , Animais , Epitopos de Linfócito T , Humanos , Imunoglobulina E , Técnicas In Vitro , Lactente , Proteínas do Leite/química , Proteínas do Leite/imunologia
11.
PLoS One ; 15(8): e0236212, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797100

RESUMO

Although an impact of processing on immunogenicity of food proteins has clearly been demonstrated, the underlying mechanisms are still unclear. We applied 3 different processing methods: wet heating (60 °C) and low- or high-temperature (50 °C or 130 °C, respectively) dry-heating in absence or presence of reducing sugars, to ß-lactoglobulin (BLG), lysozyme and thyroglobulin, which represent dietary proteins with different pI or molecular weight. Uptake of the soluble fraction of the samples was tested in two types of, genetically homogeneous, antigen-presenting cells (macrophages and dendritic cells derived from THP-1 monocytes). This revealed a strong correlation between the uptake of the different protein samples by macrophages and dendritic cells, and confirmed the key role of hydrophobicity, over aggregation, in determining the uptake. Several uptake routes were shown to contribute to the uptake of BLG by macrophages. However, cytokine responses following exposure of macrophages to BLG samples were not related to the levels of uptake. Together, our results demonstrate that heat-treatment-induced increased hydrophobicity is the prime driving factor in uptake, but not in cytokine production, by THP-1 macrophages.


Assuntos
Citocinas/metabolismo , Células Dendríticas/imunologia , Proteínas na Dieta/imunologia , Macrófagos/imunologia , Receptores de Superfície Celular/metabolismo , Culinária , Células Dendríticas/metabolismo , Proteínas na Dieta/química , Proteínas na Dieta/metabolismo , Temperatura Alta , Humanos , Interações Hidrofóbicas e Hidrofílicas , Macrófagos/metabolismo , Peso Molecular , Células THP-1
12.
Food Res Int ; 136: 109543, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32846598

RESUMO

Milk is regarded as one of the top food products susceptible to adulteration where its valuable components are specifically identified as high-risk indicators for milk fraud. The current study explores the impact of common milk adulterants on the apparent compositional parameters of milk from the Dutch market as measured by standardized Fourier transform infrared (FTIR) spectroscopy. More precisely, it examines the detectability of these adulterants at various concentration levels using the compositional parameters individually, in a univariate manner, and together in a multivariate approach. In this study we used measured boundaries but also more practical variance-adjusted boundaries to set thresholds for detection of adulteration. The potential economic impact of these adulterations under a milk payment scheme is also evaluated. Twenty-four substances were used to produce various categories of milk adulterations, each at four concentration levels. These substances comprised five protein-rich adulterants, five nitrogen-based adulterants, seven carbohydrate-based adulterants, six preservatives and water, resulting in a set of 360 samples to be analysed. The results showed that the addition of protein-rich adulterants, as well as dicyandiamide and melamine, increased the apparent protein content, while the addition of carbohydrate-based adulterants, whey protein isolate, and skimmed milk powder, increased the apparent lactose content. When considering the compositional parameters univariately, especially protein- and nitrogen-based adulterants did not raise a flag of unusual apparent concentrations at lower concentration levels. Addition of preservatives also went unnoticed. The multivariate approach did not improve the level of detection. Regarding the potential profit of milk adulteration, whey protein and corn starch seem particularly interesting. Combining the artificial inflation of valuable components, the resulting potential profit, and the gaps in detection, it appears that the whey protein isolates deserve particular attention when thinking like a criminal.


Assuntos
Contaminação de Alimentos , Leite , Animais , Contaminação de Alimentos/análise , Análise de Fourier , Lactose , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Int J Mol Sci ; 21(12)2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604964

RESUMO

Intake of dietary advanced glycation end products (AGEs) is associated with inflammation-related health problems. Nε-carboxymethyl lysine (CML) is one of the best characterised AGEs in processed food. AGEs have been described as ligands for receptors present on antigen presenting cells. However, changes in protein secondary and tertiary structure also induce binding to AGE receptors. We aimed to discriminate the role of different protein modifications in binding to AGE receptors. Therefore, ß-lactoglobulin was chemically modified with glyoxylic acid to produce CML and compared to ß-lactoglobulin glycated with lactose. Secondary structure was monitored with circular dichroism, while hydrophobicity and formation of ß-sheet structures was measured with ANS-assay and ThT-assay, respectively. Aggregation was monitored using native-PAGE. Binding to sRAGE, CD36, and galectin-3 was measured using inhibition ELISA. Even though no changes in secondary structure were observed in all tested samples, binding to AGE receptors increased with CML concentration of CML-modified ß-lactoglobulin. The negative charge of CML was a crucial determinant for the binding of protein bound CML, while binding of glycated BLG was determined by increasing hydrophobicity. This shows that sRAGE, galectin-3, and CD36 bind to protein bound CML and points out the role of negatively charged AGEs in binding to AGE receptors.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Lactoglobulinas/metabolismo , Lisina/análogos & derivados , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Animais , Bovinos , Glicosilação , Temperatura Alta , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lisina/química , Lisina/metabolismo
14.
Foods ; 9(6)2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32492929

RESUMO

This study aimed to assess the prevalence of ultra-high-temperature (UHT) processed milk samples suspected of being adulterated on the Chinese market and, subsequently, relate their geographical origin to the earlier determined fraud vulnerability. A total of 52 UHT milk samples purchased from the Chinese market were measured to detect possible anomalies. The milk compositional features were determined by standardized Fourier transform-infrared spectroscopy, and the detection limits for common milk adulterations were investigated. The results showed that twelve of the analysed milk samples (23%) were suspected of having quality or fraud-related issues, while one sample of these was highly suspected of being adulterated (diluted with water). Proportionally, more suspected samples were determined among milks produced in the Central-Northern and Eastern areas of China than in those from the North-Western and North-Eastern areas, while those from the South were in between. Combining the earlier collected results on fraud vulnerability in the Chinese milk chains, it appears that increased fraud prevalence relates to poorer business relationships and lack of adequate managerial controls. Since very few opportunities and motivations differ consistently across high and low-prevalence areas, primarily the improvement of control measures can help to mitigate food fraud in the Chinese milk supply chains.

15.
Food Funct ; 11(6): 4982-4993, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32515464

RESUMO

The allergy-protective capacity of raw cow's milk was demonstrated to be abolished after heat treatment. The heat-sensitive whey protein fraction of raw milk is often implied to be the source of this allergy-protective effect, but a direct link between these proteins and the protection against allergic diseases is missing. This study therefore aimed at investigating the mechanistic relation between heat damage to whey proteins and allergy development. Raw cow's milk was heated for 30 min at 50, 60, 65, 70, 75, or 80 °C and the native whey protein profile of these differentially heated milk samples was determined using LC-MS/MS-based proteomics. Changes in the native protein profile were subsequently related to the capacity of these milk samples to prevent the development of ovalbumin-induced food allergy in a murine animal model. A substantial loss of native whey proteins, as well as extensive protein aggregation, was observed from 75 °C. However, whey proteins with immune-related functionalities already started to denature from 65 °C, which coincided with the temperature at which a loss of allergy protection was observed in the murine model. Complement C7, monocyte differentiation antigen CD14, and polymeric immunoglobulin receptor concentrations decreased significantly at this temperature, although several other immunologically active whey proteins also showed a decrease around 65 °C. The current study demonstrates that immunologically active whey proteins that denature around 65 °C are of importance for the allergy-protective capacity of raw cow's milk and thereby provides key knowledge for the development of microbiologically safe alternatives to raw cow's milk.


Assuntos
Hipersensibilidade a Leite/imunologia , Leite/química , Proteínas do Soro do Leite/química , Animais , Feminino , Manipulação de Alimentos , Temperatura Alta , Camundongos , Camundongos Endogâmicos , Organismos Livres de Patógenos Específicos
16.
Food Chem ; 330: 127184, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531635

RESUMO

Heat treatment is a commonly applied unit operation in the processing of ß-lactoglobulin containing products. This does, however, influence its structure and thereby impacts its activity and digestibility. We describe how various heat-treatments of ß-lactoglobulin change the digestibility using a modified version of the current consensus INFOGEST protocol. Additionally, protein was investigated for its translocation over the intestinal epithelial barrier, which would bring them in contact with immune cells. The extent of gastric digestibility was higher when the protein structure was more modified, while the influence of glycation with lactose was limited. Translocation studies of protein across Caco-2 cell monolayers showed a lower translocation rate of protein heated in solution compared to the others. Our study indicates that structural modifications after different heat-treatments of ß-lactoglobulin increase in particular gastric digestibility and the translocation efficiency across intestinal epithelial cells.


Assuntos
Mucosa Gástrica , Lactoglobulinas/metabolismo , Células CACO-2 , Digestão , Glicosilação , Temperatura Alta , Humanos , Lactoglobulinas/química , Lactose/metabolismo , Estômago
17.
J Agric Food Chem ; 68(25): 6873-6883, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32496058

RESUMO

To study the Chinese human milk N-glycome over lactation, N-glycans were released and separated from serum proteins, purified by solid-phase extraction, and analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). In total, 66 different putative N-glycans were found in the colostrum (week 1) and mature milk (week 4) of seven Chinese mothers. A clear difference was observed between milk of five secretor and two nonsecretor mothers, based on the type and relative amounts of the individual N-glycans. The relative levels of the total neutral nonfucosylated and the fucosylated N-glycans in milk of five secretor mothers increased and decreased over lactation, respectively. This pattern could not be observed for the milk from the two nonsecretor mothers. Overall, this was the first study that provided detailed information on individual N-glycans in milk among mothers and over time as well as that fucosylation of N-glycans in milk was associated with the mother's secretor status.


Assuntos
Proteínas Sanguíneas/química , Colostro/química , Leite Humano/química , Polissacarídeos/química , Adulto , China , Feminino , Humanos , Mães , Gravidez , Adulto Jovem
18.
Nutrients ; 12(4)2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32331315

RESUMO

Human milk contains proteins and/or protein fragments that originate from nonhuman organisms. These proteinaceous molecules, of which the secretion might be related to the mother's allergy status, could be involved in the development of the immune system of the infant. This may lead, for example, to sensitization or the induction of allergen-specific tolerance. The aim of this study was to investigate the relation between maternal allergy and the levels of nonhuman proteinaceous molecules in their milk. In this study, we analysed trypsin-digested human milk serum proteins of 10 allergic mothers and 10 nonallergic mothers. A search was carried out to identify peptide sequences originating from bovine or other allergenic proteins. Several methods were applied to confirm the identification of these sequences, and the differences between both groups were investigated. Out of the 78 identified nonhuman peptide sequences, 62 sequences matched Bos taurus proteins. Eight peptide sequences of bovine ß -lactoglobulin had significantly higher levels in milk from allergic mothers than in milk from nonallergic mothers. Dietary bovine ß -lactoglobulin may be absorbed through the intestinal barrier and secreted into human milk. This seems to be significantly higher in allergic mothers and might have consequences for the development of the immune system of their breastfed infant.


Assuntos
Alérgenos/imunologia , Aleitamento Materno , Hipersensibilidade Alimentar/imunologia , Lactoglobulinas/análise , Lactoglobulinas/imunologia , Leite Humano/química , Mães , Animais , Bovinos , Feminino , Humanos , Lactente , Lactoglobulinas/metabolismo , Leite/química , Hipersensibilidade a Leite/imunologia , Leite Humano/metabolismo
19.
Data Brief ; 29: 105227, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32071994

RESUMO

Hereby we provide data from a shot-gun proteomics experiment, using filtered-aided sample preparation (FASP), and liquid chromatography with tandem mass spectrometry (LC-MS/MS), to relatively quantify the changes in the protein profile of whey proteins after heating milk at either 65 °C, 70 °C, 75 °C, 80 °C, or 85 °C for 30 min. The data supplied in this article supports the accompanying publication [1]. The raw mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier "PXD016436".

20.
Food Chem ; 314: 126153, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31986340

RESUMO

The relationships between the fatty acid (FA) composition in forage and milk (F&M) from different dairy systems were investigated. Eighty milk samples and 91 forage samples were collected from 40 farms (19 organic, 11 pasture and 10 conventional) in the Netherlands, during winter and summer. The FA profiles of F&M samples were measured with gas chromatography. The results showed that the F&M of organic farms were significantly differentiated from the F&M of other farms, both in summer and winter. The differences are likely due to the different grazing strategies in summer and different forage composition in winter. The Pearson's correlation results showed the specific relationship between individual FAs in forages and related milk. A PLS-DA model was applied to classify all milks samples, resulting in 87.5% and 83.3% correct classifications of training set and validation set.


Assuntos
Ácidos Graxos/análise , Leite/química , Ração Animal , Animais , Feminino , Países Baixos , Agricultura Orgânica , Estações do Ano
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