HPLC Analysis of α-lactalbumin and β-lactoglobulin in Bovine Milk with C_4 and C_(18) Column

Reversed-phase high-performance liquid chromatography （RP-HPLC） method with C4 column and C18 column for analyzing β-lactoglobulin and α-lactalbumin in bovine milk was developed and the performance and characteristic of two columns were compared. Shiseido Proteonavi C4 column （250 mm×4.6 mm×5μm） and Shiseido CAPCELL PAK SG 300 C18 column （250 mm× 4.6 mm×5 μm） were used in the experiment. Phase A was composed of 0.1% （V/V） trifluoroacetic acid （TFA） in ultrapure water and Phase B （organic phase） was composed of 0.1% TFA in acetonitrile. Gradient elution was taken. Flow rate was 1 mL min-1. The detection wavelength was 215 nm. The injection volume was 20 μL and the column temperature was 30℃. The results showed that linear relationship was good and recovery of α-lactalbumin and β-lactoglobulin was 86.12%-104.38%, C18 column had stronger ability to resist acid and more stable, and the method with C4 column had excellent sensitivities and good separation.

A metabolomics approach for monitoring thermal processing temperature of bovine milk using ultra-performance liquid chromatography tandem Q-Exactive mass spectrometry and multivariate data analysis

Due to the lack of effective assessment method,overheated milk commodities are often marketed as pasteurized milk on the market,which was sold in high price by fraud.Thus,this article aims to establish an approach based on metabolomics to monitor thermal processing temperature of bovine milk.Metabolomics data of bovine milk samples heated at temperatures ranging from 60℃to 150℃were achieved by ultra-performance liquid chromatography-high-resolution mass spectrometry(UPLC-HRMS)platform,followed by multivariate data analysis.A regular variation pattern of chemical composition as temperature rises was pictured,furthermore.N^(∈)carboxymethyl lysine(CML),N^(∈)-carboxyethyl lysine(CEL),pentosidine.pvrraline and lysinoalanine(LAL)were identified as 5 of the most contributed compounds to discriminate pasteurized and ultra-high-temperature(UHT)milk.By the comprehensive study on their content changes,we concluded that the optimal temperature range was 90-100℃for the generation of CML and CEL in this experiment,moreover.110~120℃for LAL.S0~100℃for pentosidine and 130-140℃for pvrraline.Finally,a predicted rule to discriminate pasteurized and UHT milk was preliminarily established based on the ratios of CML/CEL.CEL/pentosidine and CML/pentosidine.which could be applied in food labelling authentication of commercial bovine milk after further validation.

Effect of Carbonation on Microbiologic Parameters of Refrigerated Bovine Raw Milk

This study evaluated the effect of carbon dioxide addition on microbiological quality during refrigerated storage of raw milk collected in Curitiba city, Brazil. A three factor-two level full factorial design was used to investigate the effect of the pH （5.8-6.4）, storage time （0-10 days） and storage temperature （5-10 ℃）, on the responses, namely, mesophiles, psychrotrophs, lipolytic psychrotrophs and proteolytic psychrotrophs counts. Results showed that increase in pH and storage time had significant effect on the microbial count. No significant effect of storage temperature was observed for all the microorganisms studied. All responses were well predicted by selected mathematical models, as denoted by coefficient of determination above 0.95.

Identification of Bovine Casein Phosphorylation Using Titanium Dioxide Enrichment in Combination with Nano Electrospray Ionization Tandem Mass Spectrometry

Protein phosphorylation is an important post-translational modification that regulates milk protein structure and function.The objective of this study was to analyze the presence of phosphorylated casein.Bovine milk proteins were first separated by SDS polyacrylamide gel electrophoresis.After in gels digestion and extraction,phosphorylated peptides were enriched by titanium dioxide and identified by ultra performance liquid chromatography coupled with nano electrospray ionization tandem mass spectrometry.This method ensured the identification of 20 phosphorylated peptides,including 7 phosphorylated forms of α_s1-casein,8 α_s2-casein,and 5 β-casein.Eight phosphorylated sites derived from 3 α_s1-caseins,3 α_s2-caseins,and 2 β-caseins were also identified,and localized on residues Ser^61,Ser^63 and Ser^130 in α_s1-casein;Thr^145,Ser^146 and Ser^158 in α_s2-casein;and Ser^50 and Thr^56 in β-casein.These findings provide valuable information for investigating casein phosphorylation of the bovine milk.

Efficacy of fermented milk and whey proteins in Helicobacter pylori eradication:A review

Helicobacter pylori (H. pylori) eradication is considered a necessary step in the management of peptic ulcer disease, chronic gastritis, gastric adenocarcinoma and mucosa associated lymphoid tissue lymphoma. Standard triple therapy eradication regimens are inconvenient and achieve unpredictable and often poor results. Eradication rates are decreasing over time with increase in antibiotic resistance. Fermented milk and several of its component whey proteins have emerged as candidates for complementary therapy. In this context the current review seeks to summarize the current evidence available on their role in H. pylori eradication. Pertinent narrative/systematic reviews, clinical trials and laboratory studies on individual components including fermented milk, yogurt, whey proteins, lactoferrin, α-lactalbumin (α-LA), glycomacropeptide and immunoglobulin were comprehensively searched and retrieved from Medline, Embase, Scopus, Cochrane Controlled Trials Register and abstracts/proceedings of conferences up to May 2013. A preponderance of the evidence available on fermented milk-based probiotic preparations and bovine lactoferrin suggests a beneficial effect in Helicobacter eradication. Evidence for α-LA and immunoglobulins is promising while that for glycomacropeptide is preliminary and requires substantiation. The magnitude of the potential benefit documented so far is small and the precise clinical settings are ill defined. This restricts the potential use of this group as a complementary therapy in a nutraceutical setting hinging on better patient acceptability/compliance. Further work is necessary to identify the optimal substrate, fermentation process, dose and the ideal clinical setting (prevention/treatment, first line therapy/recurrence, symptomatic/asymptomatic, gastritis/ulcer diseases etc.). The potential of this group in high antibiotic resistance or treatment failure settings presents interesting possibilities and deserves further exploration.

The evolving role of Fourier-transform midinfrared spectroscopy in genetic improvement of dairy cattle

Over the last 100 years,significant advances have been made in the characterisation of milk composition for dairy cattle improvement programs.Technological progress has enabled a shift from labour intensive,on-farm collection and processing of samples that assess yield and fat levels in milk,to large-scale processing of samples through centralised laboratories,with the scope extended to include quantification of other traits.Fourier-transform midinfrared(FT-MIR)spectroscopy has had a significant role in the transformation of milk composition phenotyping,with spectral-based predictions of major milk components already being widely used in milk payment and animal evaluation systems globally.Increasingly,there is interest in analysing the individual FT-MIR wavenumbers,and in utilising the FT-MIR data to predict other novel traits of importance to breeding programs.This includes traits related to the nutritional value of milk,the processability of milk into products such as cheese,and traits relevant to animal health and the environment.The ability to successfully incorporate these traits into breeding programs is dependent on the heritability of the FT-MIR predicted traits,and the genetic correlations between the FT-MIR predicted and actual trait values.Linking FT-MIR predicted traits to the underlying mutations responsible for their variation can be difficult because the phenotypic expression of these traits are a function of a diverse range of molecular and biological mechanisms that can obscure their genetic basis.The individual FT-MIR wavenumbers give insights into the chemical composition of milk and provide an additional layer of granularity that may assist with establishing causal links between the genome and observed phenotypes.Additionally,there are other molecular phenotypes such as those related to the metabolome,chromatin accessibility,and RNA editing that could improve our understanding of the underlying biological systems controlling traits of interest.Here we review topics of importance to phenotyping and genetic applications of FT-MIR spectra datasets,and discuss opportunities for consolidating FT-MIR datasets with other genomic and molecular data sources to improve future dairy cattle breeding programs.

Prevention of Gut Mucosa Inflammation by Two Co-cultures of Lactobacillus plantarum-Bifidobacterium Iongum and Streptococcus thermophilus-Bifidobacterium Iongum

The effect of two fermented milks （FMI, FM2） with lactic acid bacteria and Bifidobacteria on the intestine mucosa was studied. BALB/c mice were divided in groups of non-sensitized or sensitized by oral route to cow＇s milk or colonized by FM1 [10^7 cfu/mL ofBifidobacterium longum （Bfl） and 10^8 cfu/mL of Streptococcus thermophillus （Stl）] and sensitized by oral route to cow＇s milk or colonized by FM2 [10^7 cfu/mL of Bfl and 10^7 cfu/mL ofLactobacillusplantarum （LbO）] and sensitized to cow＇s milk. Blood was sampled and the amount of anti-β-Lactoglobulin （β-Lg） IgG was measured. Mice were sacrificed, fragments of their intestines were isolated to inspect the structural changes of intestinal mucosa. A significant anti-β-Lg response was elicited by oral sensitization in positive control compared to other groups. Inspection of villi structural changes reveal signs of inflammation in challenged group compared with FM1 and FM2 groups, which conserved long villi characteristic of negative controls. The colonization of intestines by BfI-StI and BfI-LbO, and the evaluation of the residual antigenicity of β-Lg in mice sensitized to bovine milk by oral route followed by histological studies, revealed that FM1 and FM2 play protective role and reduce the histological lesions typical of bovine milk allergy.

Nutritional,rheological and sensory properties of butter processed with different mixtures of cow and sheep milk cream

This study assessed the quality parameters and consumer perception and behavior of butter processed with different ratios of cow and sheep milk cream.Cow milk cream butter(CMCB)showed lower moisture content and higher fat content,smaller fat globules,and higher concentrations of long-chain saturated fatty acids and monounsaturated fatty acids,resulting in improved potential health indices.In addition,CMCB showed yellow color,little salt,and butter taste as the main sensory characteristics,resulting in grateful and good digestibility perceptions.Sheep milk cream addition improved the rheological properties of the products(lower viscosity,consistency index,and rigidity(J0),and higher fluidity and viscoelastic behavior(J1)),mainly due to the increased concentrations of short-chain and medium-chain saturated fatty acids and polyunsaturated fatty acids.However,sheep milk cream butter(SMCB)was characterized by a greasy and striking aroma,with a lower perception of good digestibility and good appearance,and a higher bitter taste.The association of cow and sheep milk cream could be an exciting option to obtain products with improved fatty acid profiles,health indices,and yet maintain desired rheological and sensory properties.The formulation with 60%sheep milk cream and 40%cow milk cream would be the suggested combination.