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1.
J Dairy Sci ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38460870

RESUMO

Cows' milk allergy (CMA) is a common phenomenon experienced in early childhood (<5 years of age) with an average occurrence rate of roughly 2.5%. The most prevalent allergen in cows' milk is believed to be ß-lactoglobulin (ß-LG). The objective of this study was to evaluate the use of hydrophobic supercritical CO2 (ScCO2) to modify the chemical structure ß-LG thus impairing its recognition by antibodies. Whole milk powder was selected because of its closest compositional resemblance to bovine fluid milk and its applications in reconstitution and in the beverage (infant, toddler, and adult), confectionary, bakery, and meat industries. For this study, whole milk powder was treated with food-grade CO2 at temperatures of 50, 63, and 75 °C under operating pressures of 100, 150, 200, 250, and 300 bar. Proteins in whole milk powder were examined using SDS-PAGE, Western blot, and ELISA. Orbitrap Fusion LC/MS-MS and periodic staining was performed to confirm post-translational modifications in ß-LG. Functional properties of whole milk powder before and after treatment were assessed by its solubility index, oil holding capacity, emulsion capacity and stability, zeta-potential, particle size, and color analysis. SDS-PAGE of treated samples yielded fuzzy bands (variable mobility of molecules due to different MW results in ill-defined bands) indicative of an increase in molecular weight, presumably due to chemical change in the protein, and demonstrated a maximum of 71.13 ± 0.29% decrease in the band intensity of ß-LG under treatment conditions of 75 °C/300 bar for 30 min (P < 0.05). These changes were small with samples treated with heat only. Lighter, diffused bands were observed using Western blot analysis. ELISA tests proved that ScCO2 treatment specifically and significantly affected the antigenicity of ß-LG with a reduction of 42.9 ± 2.83% and 54.75 ± 2.43% at 63 °C/200 bar and 75 °C/300 bar, respectively. Orbitrap fusion detected the presence of fatty acids and sugar moieties bound to ß-LG and the latter was confirmed by periodic staining. Functional properties of ScCO2-treated milk powder yielded a decrease in solubility index and an increase in emulsion capacity of whole milk powder was observed under ScCO2 treatment at 75 °C/300 bar (P < 0.05), with small and insignificant changes at other treatments producing a decrease in antigenicity. Color changes were small for most samples, except at 63 °C/200 bar, where a significant increase in yellowness was observed. Zeta-potential and particle size measurements indicated that most changes were temperature driven. This study demonstrates 2 approaches to mitigate ß-LG antigenicity via fatty acid binding and lactosylation using hydrophobic ScCO2.

2.
Front Nutr ; 10: 1194945, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38024346

RESUMO

Bifidobacterium longum subsp. infantis is associated with the gut microbiota of breast-fed infants. Bifidobacterium infantis promotes intestinal barrier and immune function through several proposed mechanisms, including interactions between their surface polysaccharides, the host, and other gut microorganisms. Dairy foods and ingredients are some of the most conspicuous food-based niches for this species and may provide benefits for their delivery and efficacy in the gut. Milk phospholipid (MPL)-rich ingredients have been increasingly recognized for their versatile benefits to health, including interactions with the gut microbiota and intestinal cells. Therefore, our objective was to investigate the capacity for MPL to promote survival of B. infantis during simulated digestion and to modulate bacterial polysaccharide production. To achieve these aims, B. infantis was incubated with or without 0.5% MPL in de Man, Rogosa, and Sharpe (MRS) media at 37°C under anaerobiosis. Survival across the oral, gastric, and intestinal phases using in vitro digestion was measured using plate count, along with adhesion to goblet-like intestinal cells. MPL increased B. infantis survival at the end of the intestinal phase by at least 7% and decreased adhesion to intestinal cells. The bacterial surface characteristics, which may contribute to these effects, were assessed by ζ-potential, changes in surface proteins using comparative proteomics, and production of bound polysaccharides. MPL decreased the surface charge of the bifidobacteria from -17 to -24 mV and increased a 50 kDa protein (3-fold) that appears to be involved in protection from stress. The production of bound polysaccharides was measured using FTIR, HPLC, and TEM imaging. These techniques all suggest an increase in bound polysaccharide production at least 1.7-fold in the presence of MPL. Our results show that MPL treatment increases B. infantis survival during simulated digestion, induces a stress resistance surface protein, and yields greater bound polysaccharide production, suggesting its use as a functional ingredient to enhance probiotic and postbiotic effects.

3.
Microbiol Resour Announc ; 12(9): e0030423, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37526462

RESUMO

We present the draft genome sequence and assembly of Lactobacillus helveticus OSU-BDGOAK2 and Lactobacillus kefiranofaciens OSU-BDGOA1 isolated from kefir grains that exhibited in vitro antibacterial activity against Escherichia coli ATCC 25922, Listeria innocua ATCC 51742, and Staphylococcus epidermidis ATCC 1222. Genome analysis of both strains revealed gene clusters encoding bacteriocins.

4.
J Food Sci ; 88(7): 2933-2949, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37222548

RESUMO

The microbiota composition of kefir grain and milk kefir was assessed via a metagenomic approach. Significant microorganisms were isolated and identified using molecular methods. A safety assessment was conducted based on antibiotic susceptibility and blood hemolysis. Probiotic traits such as resistance to gastric tract conditions, surface characteristics, adhesion to intestinal cells, and antibacterial activity were also assessed. Metagenomic analysis revealed that kefir grains are a more stable community with clear dominant species as compared to milk kefir. Lactobacillus kefiranofaciens BDGO-A1, Lactobacillus helveticus BDGO-AK2, and Lactobacillu kefiri strains showed tolerance to acidic pH and the presence of bile salts, adhesion capability to Caco-2 cells, in vitro antibacterial activity, and the production of antibacterial proteins. In the metagenomic analysis, contigs associated with these species showed the presence of genes involved in exporting polyketide antibiotics and bacteriocin production. To fully exploit the potential probiotic properties of these microorganisms to help human health, further investigation is necessary to elucidate the mechanisms behind the biological activity and the genotypic characteristics of the isolated strains.


Assuntos
Produtos Fermentados do Leite , Kefir , Probióticos , Humanos , Animais , Kefir/microbiologia , Células CACO-2 , Leite/microbiologia , Antibacterianos/farmacologia , Produtos Fermentados do Leite/microbiologia
5.
J Dairy Sci ; 106(5): 3086-3097, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36935237

RESUMO

The relative immaturity of the infant digestive system has the potential to affect the bioavailability of dietary lipids, proteins, and their digested products. We performed a lipidomic analysis of a commercial bovine milk fat globule membrane ingredient (MFGMi) and determined the profile of lipids and proteins in the bioaccessible fraction after in vitro digestion of both the ingredient and whey-casein-based infant formula without and with MFGMi. Test materials were digested using a static 2-phase in vitro model, with conditions simulating those in the infant gut. The extent of digestion and the bioaccessibility of various classes of neutral and polar lipids were monitored by measuring a wide targeted lipid profile using direct infusion-mass spectrometry. Digestion of abundant proteins in the ingredient and whey-casein infant formula containing the ingredient was determined by denaturing PAGE with imaging of Coomassie Brilliant Blue stained bands. Cholesterol esters, diacylglycerides, triacylglycerides, phosphatidylcholines, and phosphatidylethanolamines in MFGMi were hydrolyzed readily during in vitro digestion, which resulted in marked increases in the amounts of free fatty acids and lyso-phospholipids in the bioaccessible fraction. In contrast, sphingomyelins, ceramides, and gangliosides were largely resistant to simulated digestion. Proteins in MFGMi and the infant formulas also were hydrolyzed efficiently. The results suggest that neutral lipids, cholesterol esters, phospholipids, and proteins in MFGMi are digested efficiently during conditions that simulate the prandial lumen of the stomach and small intestine of infants. Also, supplementation of whey-casein-based infant formula with MFGMi did not appear to alter the profiles of lipids and proteins in the bioaccessible fraction after digestion.


Assuntos
Caseínas , Fórmulas Infantis , Animais , Caseínas/química , Fórmulas Infantis/química , Soro do Leite/metabolismo , Ésteres do Colesterol , Digestão , Proteínas do Soro do Leite , Proteínas do Leite/metabolismo
6.
JDS Commun ; 3(2): 85-90, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36339743

RESUMO

In the midst of rising consumer health and environmental concerns, pea protein has increased in popularity as an alternative to animal-origin proteins. However, the use of pea protein in food systems is largely hindered by its poor functionality, including low solubility. The objective of this study was to measure the textural, functional, and rheological properties of a mixed plant- and animal-based protein system. Caseins, the major protein in bovine milk, are a known animal-based protein with optimal functional properties and high sensory acceptability. Through cold-temperature homogenization, insoluble pea proteins were incorporated with casein micelles in a stable, mixed, colloidal dispersion. Three blends with various casein-to-pea ratios (90:10, 80:20, 50:50) were prepared and analyzed. We hypothesized that incorporation with casein micelles would improve the poor functional properties of pea protein, and thus increase its potential uses in the food industry as a functional ingredient. The protein blend successfully underwent chymosin coagulation, a key ability of caseins, and formed protein gels with textures similar to commercial queso fresco and hard tofu. The 50% casein micelle:50% pea protein blend had better emulsification properties than pea protein alone. In contrast, this blend had the same foaming properties as pea protein alone. The mixed protein blends had similar rheological properties to skim milk, thus increasing their potential applications in the food industry. These results serve as a starting point to begin fully understanding the interactions between pea protein isolate and casein micelles combined via low-temperature homogenization and the effect on their techno-functional properties.

7.
JDS Commun ; 3(1): 1-6, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36340677

RESUMO

ß-Galactosidase is an enzyme produced by some strains of lactic acid bacteria (LAB) commonly found in dairy products; however, industrial demand for these enzymes is still low. Acid whey (AW), a lactose-rich byproduct, has large output from cottage cheese and remains unexploited. The purpose of this study was to understand the production mechanism of ß-galactosidase from LAB using AW as a culture medium. First, bioinformatics analysis was conducted on 15 species of LAB. Then, 24 strains were selected and inoculated in de Man, Rogosa, and Sharpe (MRS) broth and in AW medium to compare the bacterial kinetic growth and ß-galactosidase production. Bacterial growth and total protein activity were measured using spectrophotometric techniques. ß-Galactosidase activity was determined by 2 methods: following the hydrolysis of o-nitrophenyl-ß-d-galactopyranoside and of 5-bromo-4-chloro-3-indoyl-ß-d-galactopyranoside (X-gal) in tryptic soy agar plates. The relative expression of the ß-galactosidase gene was performed using real-time quantitative PCR. Despite generally lower growth in AW, 18 strains showed higher ß-galactosidase activity when grown in AW compared with MRS medium. The highest ß-galactosidase activity in AW was in Lactobacillus helveticus strain OSU-PECh-4A, which showed almost 5 times higher activity than average. Analysis of 6 selected strains for expression of the bgal-620 gene found higher overexpression in AW than in MRS, regardless of specific ß-galactosidase activity. Strains of LAB such as OSU-PECh-4A could valorize AW through the production of ß-galactosidase (as an aid to lactose digestion) and production of prebiotic galactooligosaccharides.

8.
ACS Food Sci Technol ; 2(9): 1442-1452, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36161074

RESUMO

Reduction of waste in the food industry is critical to sustainability. This work represents one strategy of valorizing waste streams from the dairy (acid whey) and fisheries industries (fish waste) using fermentation. The main approach was to characterize the peptides produced by this fermentation under three conditions: (1) fermentation without adding inoculum; (2) with the addition of a single lactic acid bacterial strain; and (3) the addition of a consortium of lactic acid bacteria. Previous results indicated that the rapid acidification of this fermentation was advantageous for its food safety and microbial activity. This work complements our previous results by defining the rate of peptide production due to protein digestion and using two-dimensional (2D) gel electrophoresis and proteomic analysis to give a more detailed identification of the peptides produced from different waste streams. These results provide important information on this process for eventual applications in industrial fermentation and, ultimately, the efficient valorization of these waste streams.

9.
J Agric Food Chem ; 70(26): 8124-8133, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35730749

RESUMO

Whether proteins in meat analogues (MAs) have the ability to provide equivalent nutrition as those in animal meat remains unknown. Herein, a MA was produced by high-moisture extrusion using soy and wheat proteins. The physicochemical properties, in vitro digestion, and cellular uptake of the released peptides were systematically compared between the MA and the chicken breast (CB). The MA showed a higher hardness but a lower degree of texturization than the CB. After simulated digestion, soluble peptides in the MA had a higher molecular weight and higher hydrophobicity. No observable cytotoxicity or inflammatory response to Caco-2 cells was found for both MA and CB digests. The former exhibited less permeability of peptides across Caco-2 cells. Liquid chromatography with tandem mass spectrometry found that the identified peptides in MA and CB digests contained 7-30 and 7-20 amino acid residues, respectively, and they became shorter after cellular transportation. The amino acid composition showed fewer essential and non-essential amino acids in the MA permeate than in the CB permeate.


Assuntos
Carne , Peptídeos , Aminoácidos , Animais , Células CACO-2 , Digestão , Humanos , Carne/análise , Peptídeos/metabolismo
10.
J Dairy Sci ; 105(5): 3703-3715, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35221067

RESUMO

Kefir is a fermented dairy product with well recognized probiotic properties. Recently, consumer interest in fermented products with probiotic microorganisms has increased due to the accumulating evidence of the effects of kefir microorganisms on the modulation of gut microbiota and their antimicrobial activity. Although the health properties of kefir have been reviewed in other works, the present review addresses the antimicrobial effects of kefir microbiota and associated compounds. The antimicrobial activity of kefir microorganisms could derive from different mechanisms. The microorganisms' capacity to adhere to the intestinal epithelium, preventing the adhesion of pathogens, and their immunomodulation properties are among the mechanisms suggested. Bacteria and yeast isolated from kefir have been shown to have in vivo and in vitro antimicrobial activity against enteropathogenic bacteria and spoilage fungi. However, most reports have focused their approach on single-strain antimicrobial properties; evaluation of antimicrobial activity of cocultures of kefir microbiota and their potential mechanisms of action has been neglected. Kefir microbiota and associated compounds have shown promising antimicrobial effects; however, more research needs to be done to discern the mechanisms of action.


Assuntos
Anti-Infecciosos , Produtos Fermentados do Leite , Kefir , Microbiota , Probióticos , Animais , Anti-Infecciosos/farmacologia , Produtos Fermentados do Leite/microbiologia , Kefir/microbiologia
11.
Microbiol Resour Announc ; 11(1): e0076621, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34989615

RESUMO

The Lactobacillus helveticus OSU-PECh-4A strain, from the Ohio State University Parker Chair collection, produces exceptional ß-galactosidase activity using acid whey as a culture medium, compared with a commercial broth. The strain has a genome sequence of 1,834,843 bp, and its GC content is 36.69%. Using InterProScan v5.50-84.0 software, four genes with putative ß-galactosidase function were found.

12.
J Dairy Sci ; 105(1): 22-31, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34656351

RESUMO

The dairy industry struggles to maintain consumer attention in the midst of declining fluid milk sales. Current trends create an opportunity to incorporate plant-based proteins with milk to produce a high-protein, multisourced, functional food product. Plant-based proteins, such as those in peas, can be challenging to use in food systems because of their low solubility and undesirable off-flavors. Casein micelles have unique structural properties that allow for interactions with small ions and larger macromolecules that aid in their noteworthy ability as a nanovehicle for hydrophobic compounds. The objective of this study was to use the inherent structure of the casein micelle along with common dairy processing equipment to create a stable colloidal dispersion of casein micelles with pea protein to improve its solubility in aqueous solutions. We created 3 blends with varying ratios of casein-to-pea protein (90:10, 80:20, 50:50). We subjected the mixtures to 3 cycles of homogenization using a bench-top GEA 2-stage homogenizer at 27,580 kPa maintained at 4°C, followed by pasteurization at 63°C for 30 min. The resulting blends were homogeneous liquids with increased stability due to the lack of protein precipitation. Further protein analysis by HPLC and AA sequencing revealed that vicilin, an insoluble storage protein, was the main pea protein incorporated within the casein micelle structure. These results supported our hypothesis that low-temperature homogenization can successfully be used to create a colloidal dispersion with increased stability, in which insoluble plant-based proteins may be incorporated with casein micelles in an aqueous solution. Additionally, 3-dimensional microscope images of the blends indicated a noticeable difference between the surface roughness upon addition of pea protein to the casein micelle matrix. This research highlights a promising application for other plant-based proteins to be used within the dairy industry to help drive future product innovation while also meeting current processing conditions and consumer demands.


Assuntos
Caseínas , Proteínas de Ervilha , Animais , Micelas , Leite , Solubilidade , Temperatura
13.
World J Microbiol Biotechnol ; 37(11): 196, 2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34654973

RESUMO

The gene encoding N-acetylmuramoyl-L-alanine amidase in Latilactobacillus sakei isolated from a fermented meat product was cloned in two forms: its complete sequence (AmiC) and a truncated sequence without one of its anchoring LysM domains (AmiLysM4). The objective of this work was to evaluate the effect of LysM domain deletion on antibacterial activity as well the biochemical characterization of each recombinant protein. AmiC and AmiLysM4 were expressed in Escherichia coli BL21. Using a zymography method, two bands with lytic activity were observed, which were confirmed by LC-MS/MS analysis, with molecular masses of 71 kDa (AmiC) and 66 kDa (AmiLysM4). The recombinant proteins were active against Listeria innocua and Staphylococcus aureus strains. The inhibitory spectrum of AmiLysM4 was broader than AmiC as it showed inhibition of Leuconostoc mesenteroides and Weissella viridescens, both microorganisms associated with food decomposition. Optimal temperature and pH values were determined for both proteins using L-alanine-p-nitroanilide hydrochloride as a substrate for N-acetylmuramoyl-L-alanine amidase activity. Both proteins showed similar maximum activity values for pH (8) and temperature (50 °C). Furthermore, structural predictions did not show differences for the catalytic region, but differences were found for the region called 2dom-AmiLysM4, which includes 4 of the 5 LysM domains. Therefore, modification of the LysM domain offers new tools for the development of novel food biopreservatives.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Lactobacillaceae/enzimologia , N-Acetil-Muramil-L-Alanina Amidase/química , N-Acetil-Muramil-L-Alanina Amidase/farmacologia , Antibacterianos/química , Domínio Catalítico , Clonagem Molecular , Concentração de Íons de Hidrogênio , Lactobacillaceae/genética , Testes de Sensibilidade Microbiana , Modelos Moleculares , N-Acetil-Muramil-L-Alanina Amidase/genética , N-Acetil-Muramil-L-Alanina Amidase/metabolismo , Domínios Proteicos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Temperatura
14.
World J Microbiol Biotechnol ; 37(4): 65, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33740141

RESUMO

Lactic acid bacteria are the predominant group within meat products, whose metabolites such as bacteriocins and peptidoglycan hydrolases inhibit pathogenic or spoilage bacteria. Fermented meat products, as a salami, is a good source to analyze the viable microbiota, due to these products present a low risk to consumer health. The aim of this work was to identify the lactic acid bacteria with broad antibacterial activity present in salami, purify the protein responsible for this activity, achieve antagonistic spectrum and perform the biochemical characterization. Five strains from salami were selected, isolated and identified by 16S rRNA gene sequencing. The antimicrobial activity was evaluated by antagonism assay and zymography, using spoilage microorganisms commonly found in meat products. The strain that showed a broad antibacterial activity was Latilactobacillus sakei and the antibacterial activity was given by a protein with 75-kDa of molecular mass, identified by LC/MALDI-TOF/TOF. The sequence analysis showed 67% of identity with a N-acetylmuramoyl-L-alanine amidase protein with five non-identical LysM domains. The purified protein showed an optimal pH of 8.0 and heat resistance at 80 °C for 10 min. L. sakei strain displayed antibacterial activity against Gram-negative and Gram-positive spoilage microorganisms. The results of this study provide the information to use Latilactobacillus sakei as a starter culture which will provide the necessary metabolites to combat undesirable microorganisms. Additionally, the conditions and properties for the best application and use of the antibacterial protein produced by this strain. This protein may have a potential use in the food industry as a new antibacterial agent.


Assuntos
Antibacterianos/biossíntese , Antibacterianos/farmacologia , Lactobacillus/isolamento & purificação , Lactobacillus/metabolismo , Produtos da Carne/microbiologia , N-Acetil-Muramil-L-Alanina Amidase/biossíntese , Bactérias/efeitos dos fármacos , Bacteriocinas/farmacologia , Fermentação , Alimentos Fermentados/microbiologia , Microbiologia de Alimentos , Lactobacillus/genética , Testes de Sensibilidade Microbiana , Peso Molecular , N-Acetil-Muramil-L-Alanina Amidase/genética , N-Acetil-Muramil-L-Alanina Amidase/isolamento & purificação , RNA Ribossômico 16S
15.
Microorganisms ; 9(2)2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33572211

RESUMO

The milk fat globule membrane (MFGM), the component that surrounds fat globules in milk, and its constituents have gained significant attention for their gut function, immune-boosting properties, and cognitive-development roles. The MFGM can directly interact with probiotic bacteria, such as bifidobacteria and lactic acid bacteria (LAB), through interactions with bacterial surface proteins. With these interactions in mind, increasing evidence supports a synergistic effect between MFGM and probiotics to benefit human health at all ages. This important synergy affects the survival and adhesion of probiotic bacteria through gastrointestinal transit, mucosal immunity, and neurocognitive behavior in developing infants. In this review, we highlight the current understanding of the co-supplementation of MFGM and probiotics with a specific emphasis on their interactions and colocalization in dairy foods, supporting in vivo and clinical evidence, and current and future potential applications.

16.
Microorganisms ; 9(1)2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33406784

RESUMO

The disposal of acid whey (Aw), a by-product from fermented products, is a problem for the dairy industry. The fishery industry faces a similar dilemma, disposing of nearly 50% of fish processed for human consumption. Economically feasible and science-based alternatives are needed to overcome this problem. One possible solution is to add value to the remaining nutrients from these by-products. This study focuses on the breakdown of nutrients in controlled fermentations of Aw, fish waste (F), molasses (M), and a lactic acid bacteria (LAB) strain (Lr). The aim was to assess the dynamic variations in microbial diversity and the biochemical changes that occur during fermentation. Four treatments were compared (AwF, AwFM, AwFLr, and AwFMLr), and the fermentation lasted 14 days at 22.5 °C. Samples were taken every other day. Colorimetric tests for peptide concentrations, pH, and microbial ecology by 16S-v4 rRNA amplicon using Illumina MiSeq were conducted. The results of the microbial ecology showed elevated levels of alpha and beta diversity in the samples at day zero. By day 2 of fermentation, pH dropped, and the availability of a different set of nutrients was reflected in the microbial diversity. The fermentation started to stabilize and was driven by the Firmicutes phylum, which dominated the microbial community by day 14. Moreover, there was a significant increase (3.6 times) in peptides when comparing day 0 with day 14, making this treatment practical and feasible for protein hydrolysis. This study valorizes two nutrient-dense by-products and provides an alternative to the current handling of these materials.

17.
JDS Commun ; 2(1): 1-6, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36337288

RESUMO

ß-Lactoglobulin (ß-LG) is believed to be a common allergen in bovine milk. Buttermilk (BM) powder has abundant contents of milk fat globule membrane and phospholipid, both of which have been demonstrated to have positive effects on brain and cognitive development during early infancy. This study focused on modifying ß-LG in BM via supercritical CO2 (ScCO2) treatment to modify its reactivity to antibodies and thus reduce its antigenicity. Buttermilk powder was treated in a supercritical fluid extraction system with food-grade CO2 at 100, 150, 200, 250, 350, and 400 bar at 2 temperatures, 50 and 75°C. All analyses were completed in a 10% BM suspension (wt/vol). The BM proteins were examined using sodium dodecyl sulfate (SDS)-PAGE, Western blot, ELISA, and periodic acid staining methods. Semi-purified ß-LG was used to evaluate the cytotoxicity, viability, and inflammatory response in the Caco-2 cell line by means of the lactate dehydrogenase assay, MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium] assay, and IL-8 production, respectively. The SDS-PAGE showed that the signal intensity of ß-LG bands was reduced by up to 50% after being processed at 250 bar and 75°C for 30 min. Lighter and more diffuse signals were found by Western blot, indicating modification of the protein structure. The ELISA demonstrated that ScCO2 treatment could significantly change ß-LG antigenicity in BM. Sugar moieties in bands corresponding to ß-LG were revealed by periodic acid staining, indicating glycosylation only in samples treated with ScCO2. Caco-2 cells treated with whey proteins had high viability, 24.9% lower inflammation, and no evidence of cytotoxicity compared with untreated cultures. These results showed that reduced antigenicity of ß-LG was caused by lactosylation, which has been reported as a possible pathway to reduce the allergenicity in foods. The denaturation of ß-LG by supercritical fluid processing is a promising way to address milk allergy, which remains a problem requiring more attention and further research.

18.
JDS Commun ; 2(5): 238-242, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36338387

RESUMO

Milk phospholipids (PL) are valuable dairy components that appear to impart human health benefits, including improved cognitive function in infants and adults. The commercial food industry uses primarily plant-based sources of PL, such as soy lecithin. However, it remains unclear whether different compositions of PL from different dietary sources, such as milk, convey the same benefits. We hypothesized that PL derived from bovine milk or soy have differing physiological effects in terms of inflammation due to their differences in composition. The objectives of this study were to characterize milk and soy liposomes by their physicochemical properties and composition and to evaluate their effects in vitro by means of inflammatory gene expression analyses. Milk and soy phospholipid large unilamellar vesicles (MPL-LUV and SPL-LUV, respectively) prepared using thin-film hydration coupled with extrusion were similar in terms of structure, size, and stability; however, they differed significantly in composition. The 3T3-L1 adipocytes were selected for this work because adipocytes are the main site of uptake, synthesis, modification, and breakdown of lipids and are important inflammatory mediators in mammalian systems. In this work, these cells exposed to both liposome varieties showed high biocompatibility and low cytotoxicity up to concentrations of 0.5 mg/mL as measured by colorimetric MTT and lactate dehydrogenase assays. Furthermore, SPL-LUV showed trends toward stimulating inflammation compared with MPL-LUV as measured by expression of 2 proinflammatory cytokines, monocyte chemoattractant protein-1 (MCP-1) and IL-6. Expression of MCP-1 significantly increased 1.82-fold relative to the control upon SPL-LUV treatment, with similar trends for IL-6 (increased 1.59-fold). The MPL-LUV showed relatively no change in cytokine expression. The results obtained in this work suggest that the methodology used to prepare LUV and the composition and proportion of milk PL are important in measuring cell physiology changes and inflammatory status in mammalian cells.

19.
J Dairy Sci ; 104(2): 1262-1275, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33358165

RESUMO

In recent years, acid whey production has increased due to a growing demand for Greek yogurt and acid-coagulated cheeses. Acid whey is a dairy by-product for which the industry has long struggled to find a sustainable application. Bulk amounts of acid whey associated with the dairy industry have led to increasing research on ways to valorize it. Industry players are finding ways to use acid whey on-site with ultrafiltration techniques and biodigesters, to reduce transportation costs and provide energy for the facility. Academia has sought to further investigate practical uses and benefits of this by-product. Although modern research has shown many other possible applications for acid whey, no comprehensive review yet exists about its composition, utilization, and health benefits. In this review, the industrial trends, the applications and uses, and the potential health benefits associated with the consumption of acid whey are discussed. The proximal composition of acid whey is discussed in depth. In addition, the potential applications of acid whey, such as its use as a starting material in the production of fermented beverages, as growth medium for cultivation of lactic acid bacteria in replacement of commercial media, and as a substrate for the isolation of lactose and minerals, are reviewed. Finally, the potential health benefits of the major protein constituents of acid whey, bioactive phospholipids, and organic acids such as lactic acid are described. Acid whey has promising applications related to potential health benefits, ranging from antibacterial effects to cognitive development for babies to human gut health.


Assuntos
Indústria de Laticínios/métodos , Promoção da Saúde , Soro do Leite/química , Animais , Queijo , Meios de Cultura/análise , Laticínios , Fermentação , Manipulação de Alimentos/métodos , Concentração de Íons de Hidrogênio , Ácido Láctico/análise , Lactobacillales/metabolismo , Lactose/análise , Proteínas do Soro do Leite/análise , Iogurte
20.
Front Microbiol ; 11: 608314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33362752

RESUMO

An Enterococcus durans strain, designated OSY-EGY, was previously isolated from artisanal cheese. In this work, comparative genomic and phenotypic analyses were utilized to assess the safety characteristics and probiotic traits of the bacterium. The comparative genomic analysis revealed that the strain is distantly related to potentially pathogenic Enterococcus spp. The genome was devoid of genes encoding acquired antibiotic resistance or marker virulence factors associated with Enterococcus spp. Phenotypically, the bacterium is susceptible to vancomycin, ampicillin, tetracycline, chloramphenicol, and aminoglycosides and does not have any hemolytic or gelatinase activity, or cytotoxic effect on Caco-2 cells. Altogether, these findings confirm the lack of hazardous traits in E. durans OSY-EGY. Mining E. durans OSY-EGY genome, for probiotic-related sequences, revealed genes associated with acid and bile salts tolerance, adhesion, competitiveness, antioxidant activitiy, antimicrobial activity, essential amino acids production, and vitamins biosynthesis. Phenotypically, E. durans OSY-EGY was tolerant to acidic pH (3.0), and presence of 0.3% bile salts. The bacterium showed adhesion capability to Caco-2 cells, cholesterol-lowering effect, DPPH scavenging activity, and antimicrobial activity against several Gram-positive pathogenic bacteria. Based on the current work, we propose that E. durans OSY-EGY is a potentially safe strain with desirable probiotic and antimicrobial traits. Thus, the investigated strain could be a promising candidate for several industrial applications.

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