The dynamics of individual whey protein concentrations in cows’ mammary secretions during the colostral and early lactation periods

2018 ◽  
Vol 86 (1) ◽  
pp. 88-93 ◽  
Author(s):  
Raquel F.S. Raimondo ◽  
Juliana S.P. Ferrão ◽  
Samantha I. Miyashiro ◽  
Priscila T. Ferreira ◽  
João Paulo E. Saut ◽  
...  
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Whey Proteins ◽  
Total Proteins ◽  
Mature Milk ◽  
Rennet Coagulation ◽  
Sds Page ◽  
Different Types ◽  
Biuret Method ◽  
Jersey Cows ◽  
Β Lactoglobulin

AbstractThe bovine whey consists of more than 200 different types of proteins, of which β-lactoglobulin, α-lactalbumin, serum albumin, immunoglobulins and lactoferrin predominate. However, their concentrations are not stable due to the existence of protein dynamics during a transition from colostrum secretion to mature milk. To evaluate the dynamics of whey proteins of Jersey cows during a colostral phase and first month of lactation and an influence of the number of lactations, 268 milk samples from 135 Jersey cows were selected through a clinical evaluation. Whey was obtained by rennet coagulation of the mammary secretion. The concentration of total proteins was determined by the biuret method and their fractions were identified by 12% dodecyl sulfate-polyacrylamide gel electrophoresis (12% SDS-PAGE). Maximum concentrations of all protein fractions were observed in the first 12 h of lactation, reducing over the course of the study. Modification of the protein predominance was also observed. The transition from colostrum secretion to milk occurred between 24 and 72 h postpartum. There was an influence of the number of lactations on the dynamics of whey proteins, indicating that multiparous cows had better immunological and nutritional quality when compared to primiparous cows.

Peculiarities of extraction of β-lactoglobuline in protein mineral concentrates at electroactivation of whey

2020 ◽  
Vol 2 (1) ◽  
pp. 52-68
Author(s):  
Mircea BOLOGA ◽  
Elvira VRABIE ◽  
Irina PALADII ◽  
Olga ILIASENCO ◽  
Tatiana STEPURINA ◽  
...  
Keyword(s):  
Protein Content ◽  
Whey Proteins ◽  
Sodium Dodecyl ◽  
Total Protein Content ◽  
Treatment Regimens ◽  
Sds Page ◽  
Different Types ◽  
Lower Protein ◽  
Β Lactoglobulin ◽  
Excellent Source

Introduction. Whey is a by-product and an excellent source of proteins that is rather aggressive due to a large amount of organic substances it contains. The electro-activation of whey applied in the experiments is a wasteless method that allows the va-lorification of all whey components. β-lactoglobulin (β-Lg) makes up 50% of the whey proteins and 12% of the total protein content in milk. Material and methods. The recovery of β-Lg in protein-mineral concentrates (PMC) by electro-activation processing of different types of whey with different initial protein content was investigated in seven configurations. The recovery of protein fractions in the PMCs were analyzed via electrophoresis with sodium dodecyl sulfate (SDS-PAGE) and 15% non-denaturing polyacrylamide gel (PAAG).      Results. Whey electro-fractionation and the obtaining of PMCs with predetermined protein content, namely of β-Lg, were studied on three whey types, processed at different treatment regimens and in seven configurations. The proper management of electroactivation by varying the treatment regimens will allow the electro-fractionation of different types of dairy by-products. Conclusions. The maximum amount of β-Lg recovered in PMCs on electroactivation is  66-71% depending on the processed whey and on the treatment regimens. Obviously, the extraction of β-Lg from initially lower protein content shows a higher recovery degree of β-Lg. The registered temperatures allows formation of PMCs without thermal denaturation.

scholarly journals Determination of whey proteins in different types of milk

2014 ◽  
Vol 83 (1) ◽  
pp. 67-72 ◽  
Author(s):  
Lenka Ruprichová ◽  
Michaela Králová ◽  
Ivana Borkovcová ◽  
Lenka Vorlová ◽  
Iveta Bedáňová
Keyword(s):  
High Performance ◽  
Dairy Product ◽  
Whey Proteins ◽  
Reversed Phase ◽  
Cow’S Milk ◽  
Cow's Milk ◽  
Goat’S Milk ◽  
Different Types ◽  
Goat's Milk ◽  
Β Lactoglobulin

Protein analysis is very important both in terms of milk protein allergy, and of milk and dairy product adulteration (β-lactoglobulin may be an important marker in the detection of milk adulteration). The aim of this study was to detect major whey proteins α-lactalbumin and β-lactoglobulin and their genetic variants by reversed-phase high-performance liquid chromatography. Milk samples from cows (n = 40), goats (n = 40) and sheep (n = 40) were collected at two farms and milk bars in the Czech Republic from April to June 2010. The concentration of α-lactalbumin was higher in goat’s milk (1.27 ± 0.05 g·l-1, P < 0.001) and cow’s milk (1.16 ± 0.02 g·l-1, P = 0.0037) compared to sheep’s milk (0.95 ± 0.06 g·l-1); however, concentration of α-lactalbumin in goat’s milk and cow’s milk did not differ significantly (P < 0.05). Goat’s milk contained less β-lactoglobulin (3.07 ± 0.08 g·l-1) compared to cow’s milk (4.10 ± 0.04 g·l-1, P < 0.001) or sheep’s milk (5.97 ± 0.24 g·l-1, P < 0.001). A highly significant positive correlation (r = 0.8686; P < 0.001) was found between fraction A and B of β-lactoglobulin in sheep’s milk, whereas in cow’s milk there was a negative correlation (r = -0.3010; P = 0.0296). This study summarizes actual information of the whey protein content in different types of milk which may be relevant in assessing their allergenic potential.

scholarly journals MAJOR GOAT MILK PROTEIN: SEPARATION AND CHARACTERIZATION BY “LAB-ON-A-CHIP” MICROFLUIDIC ELECTROPHORES

2018 ◽  
Vol 35 (2) ◽  
Author(s):  
ALESSA SIQUEIRA DE O. DOS SANTOS ◽  
VANEIDA MARIA MEURER ◽  
FABIANO FREIRE COSTA ◽  
IGOR MOURA DE PAIVA ◽  
GISELE NOGUEIRA FOGAÇA ◽  
...  
Keyword(s):  
Protein Separation ◽  
Whey Proteins ◽  
Milk Proteins ◽  
Goat Milk ◽  
Lab On A Chip ◽  
Cow Milk ◽  
Total Percentage ◽  
Chip Technology ◽  
Sds Page ◽  
Β Lactoglobulin

This work presents the electrophoretic profile of goat and cow milk samples and their mixtures using microfluidic and conventional electrophoresis. The microfluidic method allowed the separation of the major caseins from milk, excepting the goat κ-casein.  Besides, the major whey proteins were separated with perfect distinction of A and B β-lactoglobulin variants. Comparing to SDS-PAGE, a variation in the molecular weight was observed in all milk proteins. However, A and B β-lactoglobulin variants could not be isolated using SDS-PAGE. Although urea-PAGE did not show high resolution among whey proteins, γ-, κ-, β-, and α-caseins were clearly identified. This method also showed a lower limit detection of cow milk in mixture samples than the "lab-on-a-chip" electrophoresis. In both methods, the highest linearity obtained from plotting total percentage against cow milk concentration was observed by using cow αs1-casein (R2 = 0.986 and R² = 0.973). This result indicates that microfluidic electrophoresis is an effective tool to detect the presence of some proteins in goat and cow milk, and in mixtures. Microfluidic chip technology might will complement the current methods for analyzing milk proteins, highlighting its speed amount of reagents and whey protein separation, which showed a better result than urea or SDS-PAGE

scholarly journals Digestibility of β-lactoglobulin following cross-linking by trametes versicolor laccase and apple polyphenols

2011 ◽  
Vol 76 (6) ◽  
pp. 847-855 ◽  
Author(s):  
Ziyad Tantoush ◽  
Luka Mihajlovic ◽  
Bojana Kravic ◽  
Jana Ognjenovic ◽  
Ratko Jankov ◽  
...  
Keyword(s):  
Nutritional Value ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Cross Linking ◽  
Allergenic Potential ◽  
Sds Page ◽  
Molecular Masses ◽  
Quercetin Glycosides ◽  
Phenolic Extract ◽  
Β Lactoglobulin

?-Lactoglobulin (BLG) is an important nutrient of dairy products and an important allergen in cow?s milk allergy. The aim of this study was to investigate the potential of laccase to cross-link BLG in the presence of an apple phenolic extract (APE) and to characterize the obtained products for their digestibility by pepsin and pancreatin. The composition of the apple phenolics used for cross-linking was determined by LC-ESE-MS. The apple phenolic extract contained significant amounts of quercetin glycosides, catechins and chlorogenic acid. The laccase cross-linked BLG in the presence of apple phenolics. The polymerization rendered the protein insoluble in the reaction mixture. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of the cross-linking reaction mixture revealed a heterogeneous mixture of high molecular masses (cross-linked BLG), with a fraction of the BLG remaining monomeric. Enzymatic processing of BLG by laccase and apple polyphenols as mediators can decrease the bi-phasal pepsin- pancreatin digestibility of the monomeric and cross-linked protein, thus decreasing its nutritional value. In addition, reduced BLG digestibility can decrease its allergenic potential. Apple polyphenols can find usage in the creation of new, more functional food products, designed to prevent obesity and hypersensitivity-related disorders.

Kinetics of heat-induced whey protein denaturation and aggregation in skim milks with adjusted whey protein concentration

2005 ◽  
Vol 72 (3) ◽  
pp. 369-378 ◽  
Author(s):  
David J Oldfield ◽  
Harjinder Singh ◽  
Mike W Taylor
Keyword(s):  
Whey Protein ◽  
Protein Concentration ◽  
Protein Denaturation ◽  
Polyacrylamide Gel Electrophoresis ◽  
Whey Proteins ◽  
Pilot Scale ◽  
Casein Micelles ◽  
Reaction Orders ◽  
Β Lactoglobulin ◽  
Kinetics Of

Microfiltration and ultrafiltration were used to manufacture skim milks with an increased or reduced concentration of whey proteins, while keeping the casein and milk salts concentrations constant. The skim milks were heated on a pilot-scale UHT plant at 80, 90 and 120 °C. The heat-induced denaturation and aggregation of β-lactoglobulin (β-lg), α-lactalbumin (α-la) and bovine serum albumin (BSA) were quantified by polyacrylamide gel electrophoresis. Apparent rate constants and reaction orders were calculated for β-lg, α-la and BSA denaturation. Rates of β-lg, α-la and BSA denaturation increased with increasing whey protein concentration. The rate of α-la and BSA denaturation was affected to a greater extent than β-lg by the change in whey protein concentration. After heating at 120 °C for 160 s, the concentration of β-lg and α-la associated with the casein micelles increased as the initial concentration of whey proteins increased.

scholarly journals Effect of Protein Genotypes on Physicochemical Properties and Protein Functionality of Bovine Milk: A Review

Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2409
Author(s):  
Nan Gai ◽  
Therese Uniacke-Lowe ◽  
Jonathan O’Regan ◽  
Hope Faulkner ◽  
Alan L. Kelly
Keyword(s):  
Physicochemical Properties ◽  
Genetic Variants ◽  
Whey Proteins ◽  
Bovine Milk ◽  
Milk Proteins ◽  
Heat Stability ◽  
Foaming Properties ◽  
Rennet Coagulation ◽  
Acid Gel ◽  
Β Lactoglobulin

Milk protein comprises caseins (CNs) and whey proteins, each of which has different genetic variants. Several studies have reported the frequencies of these genetic variants and the effects of variants on milk physicochemical properties and functionality. For example, the C variant and the BC haplotype of αS1-casein (αS1-CN), β-casein (β-CN) B and A1 variants, and κ-casein (κ-CN) B variant, are favourable for rennet coagulation, as well as the B variant of β-lactoglobulin (β-lg). κ-CN is reported to be the only protein influencing acid gel formation, with the AA variant contributing to a firmer acid curd. For heat stability, κ-CN B variant improves the heat resistance of milk at natural pH, and the order of heat stability between phenotypes is BB > AB > AA. The A2 variant of β-CN is more efficient in emulsion formation, but the emulsion stability is lower than the A1 and B variants. Foaming properties of milk with β-lg variant B are better than A, but the differences between β-CN A1 and A2 variants are controversial. Genetic variants of milk proteins also influence milk yield, composition, quality and processability; thus, study of such relationships offers guidance for the selection of targeted genetic variants.

The quantitative measurement of whey proteins using polyacrylamide-gel electrophoresis

1976 ◽  
Vol 43 (2) ◽  
pp. 259-265 ◽  
Author(s):  
Robyn M. Hillier
Keyword(s):  
Gel Electrophoresis ◽  
Protein Denaturation ◽  
Quantitative Estimation ◽  
Polyacrylamide Gel Electrophoresis ◽  
Whey Proteins ◽  
Skim Milk ◽  
Internal Standard ◽  
Polyacrylamide Gel ◽  
Native Whey ◽  
Β Lactoglobulin

SummaryA method is described for the quantitative estimation of a mixture of whey proteins by spectrophotometric scanning of the stained protein bands following polyacrylamide-gel electrophoresis. The incorporation of β-lactoglobulin A as an internal standard improves the accuracy of the technique. The method has been used to measure residual native whey proteins in milk after heating. Results are presented for whey protein denaturation in skim-milk after heat treatment at 130 and 140 °C for various periods of time.

Reduction of aggregation of β-lactoglobulin during heating by dihydrolipoic acid

2013 ◽  
Vol 80 (4) ◽  
pp. 383-389 ◽  
Author(s):  
Heni B Wijayanti ◽  
H Eustina Oh ◽  
Ranjan Sharma ◽  
Hilton C Deeth
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Whey Proteins ◽  
Heat Stability ◽  
Size Exclusion ◽  
Reduced Form ◽  
Dihydrolipoic Acid ◽  
Sh Group ◽  
Covalently Linked ◽  
Induced Aggregation ◽  
Β Lactoglobulin

Prevention of the heat-induced aggregation of β-lactoglobulin (β-Lg) would improve the heat stability of whey proteins. The effects of lipoic acid (LA, or thioctic acid), in both its oxidised and reduced form (dihydrolipoic acid, DHLA), on heat-induced unfolding and aggregation of β-Lg were investigated. LA/DHLA was added to native β-Lg and the mixture was heated at 70, 75, 80 or 85 °C for up to 30 min at pH 6·8. The samples were analysed by Polyacrylamide Gel Electrophoresis (PAGE) and Size-exclusion HPLC (SE-HPLC). LA was not as effective as DHLA in reducing the formation of aggregates of heated β-Lg. Heating β-Lg with DHLA resulted in formation of more β-Lg monomers (due to dissociation of native dimers) and significantly less β-Lg aggregates, compared with heating β-Lg alone. The aggregates formed in the presence of DHLA were both covalently linked, via disulphide bonds, and non-covalently (hydrophobically) linked, but the amount of covalently linked aggregates was much less than when β-Lg was heated alone. The results suggest that DHLA was able to partially trap the reactive β-Lg monomer containing a free sulphydryl (−SH) group, by forming a ‘modified monomer’, and to prevent some sulphydryl−sulphydryl and sulphydryl−disulphide interactions that lead to the formation of covalently linked protein aggregates. The effects of DHLA were similar to those of N-ethylmaleimide (NEM) and dithio(bis)-p-nitrobenzoate (DTNB). However, the advantage of using DHLA over NEM and DTNB to lessen aggregation of β-Lg is that it is a food-grade compound which occurs naturally in milk.

scholarly journals Study on milk composition and milk protein distribution in Romanian Holstein cattle

2020 ◽  
Vol 23 (1) ◽  
pp. 13-21
Author(s):  
Rodica Ştefania Pelmuş ◽  
Cristina Lazăr ◽  
M. L. Palade ◽  
Mariana Stancu ◽  
C. M. Rotar ◽  
...  
Keyword(s):  
Milk Protein ◽  
Whey Proteins ◽  
Milk Proteins ◽  
Protein Composition ◽  
Holstein Cattle ◽  
Protein Distribution ◽  
Quality Indices ◽  
Milk Samples ◽  
Sds Page ◽  
Β Lactoglobulin

AbstractThe aim of this study was to determine milk quality indices as well as the milk protein composition in Romanian Holstein cattle raised under the conditions of experimental farm of INCDBNA-IBNA. The study was carried out on 22 milk samples. The types of different milk proteins were identified by SDS-PAGE technique. Sampling day and milk chemical composition were performed during the milking period of studied cattle. The quality indices were breed-specific for protein (3.38%) and higher for fat (4.39%).Milk proteins analysis of Romanian Holstein cattle separated by SDS-PAGE electrophoresis showed the presence of four major caseins (αs1-, αs2-, β- and k-casein) and two whey proteins (β-lactoglobulin, α-lactalbumin). The caseins accounted 77.28% of the total milk proteins, while the major proteins (β-lactoglobulin, α-lactalbumin) from the whey represented 22.72% of the total proteins. αs1-casein + αs2-casein had a higher expression (36.01%) followed by β-casein (31.45%), β-lactoglobulin (18.16%), k-casein (9.82%) and α-lactalbumin (4.56%). The most of milk samples was characterized by a medium expression level of both caseins and whey proteins

scholarly journals β-lactoglobulin peptides obtained by chymotrypsin hydrolysis

2021 ◽  
Author(s):  
Brayan Aguilar-Ovando ◽  
Georgina Calderón-Domínguez ◽  
Mariano García-Garibay ◽  
Judith Jiménez-Guzmán ◽  
Eduardo Jardón-Valadez ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Biological Activity ◽  
Inhibitory Activity ◽  
Whey Proteins ◽  
In Vitro Hydrolysis ◽  
Different Types ◽  
Β Lactoglobulin ◽  
Hydrolysis Of ◽  
Controlled Hydrolysis

Objective: Whey proteins, as β-lactoglobulin, have biological activity. Controlled hydrolysis of this protein could generate peptides with some biological function. The aim of this work was to analyze the peptides resulting from the in vitro hydrolysis with chymotrypsin in order to evaluate the presence of bioactive peptides. Design/methodology/approach: Chymotrypsin was used in the hydrolysis of β-lactoglobulin, and its peptides were evaluated by ultrafiltration, electrophoresis, and mass spectrometry. Findings/conclusion: Results showed that 2 h of chymotrypsin hydrolysis (T1) released peptides with molecular weight values of 8 and 9 KDa, while 4 h of hydrolysis (T2) produced peptides with molecular mass weight values of 7 and 5 KDa. The mass spectrometry (MALDI-TOF) showed six peaks and five of them were comparable with those obtained by in silico hydrolysis results (done previously by Fonseca Ayala, 2018). The identified peptides (DTDYK, DAQSAPL and LKPTPEGDL) in the fraction <1 kDa showed inhibitory activity of angiotensin converting enzyme and inhibitory activity of enzyme dipeptidyl peptidase IV according BIOPEP database. These results showed that β-lactoglobulin peptides obtained by chymotrypsin hydrolysis could have biological activity that can be used in different types of industries as pharmaceutical and food. Limitations on study/implications: The in vitro evaluation of the biological activity of the characterized peptides is necessary.

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