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Sample records for caseins

  1. Bovine β-casein

    NARCIS (Netherlands)

    Atamer, Zeynep; Post, Antonie E.; Schubert, Thomas; Holder, Aline; Boom, Remko Marcel; Hinrichs, Jörg

    2017-01-01

    In recent years there has been an increasing interest in pure casein fractions, particularly β-casein due to its physiochemical properties as well as its bio- and techno-functional properties. A range of methods has been developed for the fractionation of casein into its individual proteins. The

  2. Natural variation in casein composition of milk

    NARCIS (Netherlands)

    Bijl, E.

    2014-01-01

    Bovine milk contains 3-4 % protein and almost 80% of the milk protein fraction consist of four caseins; αs1-casein, β-casein, αs2-casein and κ-casein. Most of the caseins in milk are assembled in casein micelles, which consist of several thousands of indi

  3. The association of lysozyme with casein

    NARCIS (Netherlands)

    Roos, de A.L.; Walstra, P.; Geurts, T.J.

    1998-01-01

    The association of hen eggs’ lysozyme with caseins was studied by using three casein substrates: (I) solutions of the various caseins, (II) artificially made casein micelles of various compositions and (III) caseins adsorbed onto soya-oil emulsion droplets. In solution, lysozyme associated most stro

  4. Casein nomenclature, structure and association

    Science.gov (United States)

    This chapter of the Encyclopedia of Dairy Science deals with the recent developments in the nomenclature, classification, structures, and associations of the major milk proteins: the caseins. Identification of the caseins continues to be based upon their primary structures. Significant findings re...

  5. Chymosin-induced hydrolysis of caseins: Influence of degree of phosphorylation of alpha-s1-casein and genetic variants of beta-casein

    NARCIS (Netherlands)

    Bijl, E.; Valenberg, van H.J.F.; Sikkes, S.; Jumelet, S.; Sala, G.; Olieman, K.; Hooijdonk, van A.C.M.; Huppertz, T.

    2014-01-01

    The objective of this study was to investigate the impact of natural variations in aS1-casein and b-casein composition of milk on chymosin-induced hydrolysis of these caseins in milk gels and in sodium caseinate solutions. At 50% casein degradation, 15% more of aS1-casein with eight phosphate groups

  6. Development of casein microgels from cross-linking of casein micelles by genipin.

    Science.gov (United States)

    Silva, Naaman F Nogueira; Saint-Jalmes, Arnaud; de Carvalho, Antônio F; Gaucheron, Frédéric

    2014-09-02

    Casein micelles are porous colloidal particles, constituted of casein molecules, water, and minerals. The vulnerability of the supramolecular structure of casein micelles face to changes in the environmental conditions restrains their applications in other domains besides food. Thus, redesigning casein micelles is a challenge to create new functionalities for these biosourced particles. The objective of this work was to create stable casein microgels from casein micelles using a natural cross-linker, named genipin. Suspensions of purified casein micelles (25 g L(-1)) were mixed with genipin solutions to have final concentrations of 5, 10, and 20 mM genipin. Covalently linked casein microgels were formed via cross-linking of lysyl and arginyl residues of casein molecules. The reacted products exhibited blue color. The cross-linking reaction induced gradual changes on the colloidal properties of the particles. The casein microgels were smaller and more negatively charged and presented smoother surfaces than casein micelles. These results were explained based on the cross-linking of free NH2 present in an external layer of κ-casein. Light scattering and rheological measurements showed that the reaction between genipin and casein molecules was intramicellar, as one single population of particles was observed and the values of viscosity (and, consequently, the volume fraction of the particles) were reduced. Contrary to the casein micelles, the casein microgels were resistant to the presence of dissociating agents, e.g., citrate (calcium chelating) and urea, but swelled as a consequence of internal electrostatic repulsion and the disruption of hydrophobic interactions between protein chains. The casein microgels did not dissociate at the air-solution interface and formed solid-like interfaces rather than a viscoelastic gel. The potential use of casein microgels as adaptable nanocarriers is proposed in the article.

  7. Casein Micelle Dispersions under Osmotic Stress

    OpenAIRE

    Bouchoux, Antoine; Cayemitte, Pierre-Emerson; Jardin, Julien; Gésan-Guiziou, Geneviève; Cabane, Bernard

    2009-01-01

    Casein micelles dispersions have been concentrated and equilibrated at different osmotic pressures using equilibrium dialysis. This technique measured an equation of state of the dispersions over a wide range of pressures and concentrations and at different ionic strengths. Three regimes were found. i), A dilute regime in which the osmotic pressure is proportional to the casein concentration. In this regime, the casein micelles are well separated and rarely interact, whereas the osmotic press...

  8. Rheology and structural arrest of casein suspensions

    OpenAIRE

    Dahbi, Louisa; Alexander, M.; Trappe, Véronique; Dhont, J. K. G.; Schurtenberger, Peter

    2010-01-01

    The rheology of milk powder suspensions is investigated up to very high concentrations, where structural arrest occurs. The main component of the milk powder investigated is casein, so that the suspensions can be regarded as casein suspensions. Four concentration regimes are identified. For effective casein volume fractions less than 0.54 the concentration dependence of the zero-shear viscosity is similar to that of hard-sphere suspensions. However, due to the elastic deformation of the casei...

  9. Milk Intolerance, Beta-Casein and Lactose.

    Science.gov (United States)

    Pal, Sebely; Woodford, Keith; Kukuljan, Sonja; Ho, Suleen

    2015-08-31

    True lactose intolerance (symptoms stemming from lactose malabsorption) is less common than is widely perceived, and should be viewed as just one potential cause of cows' milk intolerance. There is increasing evidence that A1 beta-casein, a protein produced by a major proportion of European-origin cattle but not purebred Asian or African cattle, is also associated with cows' milk intolerance. In humans, digestion of bovine A1 beta-casein, but not the alternative A2 beta-casein, releases beta-casomorphin-7, which activates μ-opioid receptors expressed throughout the gastrointestinal tract and body. Studies in rodents show that milk containing A1 beta-casein significantly increases gastrointestinal transit time, production of dipeptidyl peptidase-4 and the inflammatory marker myeloperoxidase compared with milk containing A2 beta-casein. Co-administration of the opioid receptor antagonist naloxone blocks the myeloperoxidase and gastrointestinal motility effects, indicating opioid signaling pathway involvement. In humans, a double-blind, randomized cross-over study showed that participants consuming A1 beta-casein type cows' milk experienced statistically significantly higher Bristol stool values compared with those receiving A2 beta-casein milk. Additionally, a statistically significant positive association between abdominal pain and stool consistency was observed when participants consumed the A1 but not the A2 diet. Further studies of the role of A1 beta-casein in milk intolerance are needed.

  10. Milk Intolerance, Beta-Casein and Lactose

    Directory of Open Access Journals (Sweden)

    Sebely Pal

    2015-08-01

    Full Text Available True lactose intolerance (symptoms stemming from lactose malabsorption is less common than is widely perceived, and should be viewed as just one potential cause of cows’ milk intolerance. There is increasing evidence that A1 beta-casein, a protein produced by a major proportion of European-origin cattle but not purebred Asian or African cattle, is also associated with cows’ milk intolerance. In humans, digestion of bovine A1 beta-casein, but not the alternative A2 beta-casein, releases beta-casomorphin-7, which activates μ-opioid receptors expressed throughout the gastrointestinal tract and body. Studies in rodents show that milk containing A1 beta-casein significantly increases gastrointestinal transit time, production of dipeptidyl peptidase-4 and the inflammatory marker myeloperoxidase compared with milk containing A2 beta-casein. Co-administration of the opioid receptor antagonist naloxone blocks the myeloperoxidase and gastrointestinal motility effects, indicating opioid signaling pathway involvement. In humans, a double-blind, randomized cross-over study showed that participants consuming A1 beta-casein type cows’ milk experienced statistically significantly higher Bristol stool values compared with those receiving A2 beta-casein milk. Additionally, a statistically significant positive association between abdominal pain and stool consistency was observed when participants consumed the A1 but not the A2 diet. Further studies of the role of A1 beta-casein in milk intolerance are needed.

  11. Focusing on the goat casein complex.

    Science.gov (United States)

    Caroli, A; Chiatti, F; Chessa, S; Rignanese, D; Bolla, P; Pagnacco, G

    2006-08-01

    The analysis of casein polymorphisms in goat species is rather difficult, because of a large number of mutations at each locus, and the tight linkage involving the 4 casein genes. Three goat breeds from Northern Italy, Orobica, Verzasca, and Frisa, were analyzed at the casein complex by milk isoelectrofocusing and analyses at the DNA level to identify the majority of all known polymorphisms. The casein gene structure of the 3 local breeds at alpha(S1)-casein (CSN1S1), beta-casein (CSN2), alpha(S2)-casein (CSN1S2), and kappa-casein (CSN3) was compared with that of Camosciata, a more widely distributed breed. A new allele was identified and characterized at CSN2 gene, which seemed to be specific to the Frisa breed. It was named CSN2*E, and was characterized by a transversion TCT --> TAT responsible for the amino acid exchange Ser(166) --> Tyr(166) in the mature protein. The casein haplotype structure is highly different among breeds. A total of 26 haplotypes showed a frequency higher than 0.01 in at least 1 of the 4 breeds considered, with 12, 3, 5, and 19 haplotypes in Frisa, Orobica, Verzasca, and Camosciata breeds, respectively. Only 13 haplotypes occurred at a frequency higher than 0.05 in at least 1 breed. With the molecular knowledge of each locus, the ancestral haplotype coding for CSN1S1*B, CSN2*A, CSN1S2*A, and CSN3*B protein variants can be postulated. A protein evolutionary model considering the whole casein haplotype is proposed.

  12. Stability of casein micelles in milk

    Science.gov (United States)

    Tuinier, R.; de Kruif, C. G.

    2002-07-01

    Casein micelles in milk are proteinaceous colloidal particles and are essential for the production of flocculated and gelled products such as yogurt, cheese, and ice-cream. The colloidal stability of casein micelles is described here by a calculation of the pair potential, containing the essential contributions of brush repulsion, electrostatic repulsion, and van der Waals attraction. The parameters required are taken from the literature. The results are expressed by the second osmotic virial coefficient and are quite consistent with experimental findings. It appears that the stability is mainly attributable to a steric layer of κ-casein, which can be described as a salted polyelectrolyte brush.

  13. Effects of hydrolysed casein, intact casein and intact whey protein on energy expenditure and appetite regulation

    DEFF Research Database (Denmark)

    Bendtsen, Line Quist; Lorenzen, Janne Kunchel; Gomes, Sisse

    2014-01-01

    Casein and whey differ in amino acid composition and in the rate of absorption; however, the absorption rate of casein can be increased to mimic that of whey by exogenous hydrolysis. The objective of the present study was to compare the effects of hydrolysed casein (HC), intact casein (IC......) and intact whey (IW) on energy expenditure (EE) and appetite regulation, and thereby to investigate the influence of amino acid composition and the rate of absorption. In the present randomised cross-over study, twenty-four overweight and moderately obese young men and women consumed three isoenergetic...

  14. COMPARATIVE STUDY ON MILK CASEIN ASSAY METHODS

    Directory of Open Access Journals (Sweden)

    RODICA CĂPRIłĂ

    2013-12-01

    Full Text Available Casein, the main milk protein was determined by different assay methods: the gravimetric method, the method based on the neutralization of the NaOH excess used for the casein precipitate solving and the method based on the titration of the acetic acid used for the casein precipitation. The last method is the simplest one, with the fewer steps, and also with the lowest error degree. The results of the experiment revealed that the percentage of casein from the whole milk protein represents between 72.6–81.3% in experiment 1, between 73.6–81.3% in experiment 2 and between 74.3–81% in experiment 3.

  15. Casein micelles and their internal structure

    Energy Technology Data Exchange (ETDEWEB)

    De Kruif, Cornelis G [ORNL; Huppertz, Thom [NIZO Food Research; Urban, Volker S [ORNL; Petukhov, Andrei V [Van ' t Hoff laboratory for Physical and Colloid Chemistry, Utrecht University, The Netherlands

    2012-01-01

    The internal structure of casein micelles was studied by calculating the small-angle neutron and X-ray scattering and static light scattering spectrum (SANS, SAXS, SLS) as a function of the scattering contrast and composition. We predicted experimental SANS, SAXS, SLS spectra self consistently using independently determined parameters for composition size, polydispersity, density and voluminosity. The internal structure of the casein micelles, i.e. how the various components are distributed within the casein micelle, was modeled according to three different models advocated in the literature; i.e. the classical sub-micelle model, the nanocluster model and the dual binding model. In this paper we present the essential features of these models and combine new and old experimental SANS, SAXS, SLS and DLS scattering data with new calculations that predict the spectra. Further evidence on micellar substructure was obtained by internally cross linking the casein micelles using transglutaminase, which led to casein nanogel particles. In contrast to native casein micelles, the nanogel particles were stable in 6 M urea and after sequestering the calcium using trisodium citrate. The changed scattering properties were again predicted self consistently. An important result is that the radius of gyration is independent of contrast, indicating that the mass distribution within a casein micelle is homogeneous. Experimental contrast is predicted quite well leading to a match point at a D{sub 2}O volume fraction of 0.41 ratio in SANS. Using SANS and SAXS model calculations it is concluded that only the nanocluster model is capable of accounting for the experimental scattering contrast variation data. All features and trends are predicted self consistently, among which the 'famous' shoulder at a wave vector value Q = 0.35 nm{sup -1}. In the nanocluster model, the casein micelle is considered as a (homogeneous) matrix of caseins in which the colloidal calcium phosphate (CCP

  16. Structure-rheology relations in sodium caseinate containing systems

    NARCIS (Netherlands)

    Ruis, H.G.M.

    2007-01-01

    The general aim of the work described in this thesis was to investigate structure-rheologyrelations for dairy related products, focusing on model systems containing sodium caseinate. The acid inducedgelationof sodium caseinate, of sodium caseinate

  17. Factors influencing casein micelle size in milk of individual cows: Genetic variants and glycosylation of k-casein

    NARCIS (Netherlands)

    Bijl, E.; Vries, de R.F.M.; Valenberg, van H.J.F.; Huppertz, T.; Hooijdonk, van A.C.M.

    2014-01-01

    The average casein micelle size varies widely between milk samples of individual cows. The factors that cause this variation in size are not known but could provide more insight into casein micelle structure and into the physiology of casein micelle formation. The objective of this research was ther

  18. Casein - whey protein interactions in heated milk

    NARCIS (Netherlands)

    Vasbinder, Astrid Jolanda

    2003-01-01

    Heating of milk is an essential step in the processing of various dairy products, like for example yoghurt. A major consequence of the heat treatment is the denaturation of whey proteins, which either associate with the casein micelle or form soluble whey protein aggregates. By combination of enzyma

  19. Short communication: separation and quantification of caseins and casein macropeptide using ion-exchange chromatography.

    Science.gov (United States)

    Holland, B; Rahimi Yazdi, S; Ion Titapiccolo, G; Corredig, M

    2010-03-01

    The aim of this work was to improve an existing method to separate and quantify the 4 major caseins from milk samples (i.e., containing whey proteins) using ion-exchange chromatography. The separation process was carried out using a mini-preparative cation exchange column (1 or 5mL of column volume), using urea acetate as elution buffer at pH 3.5 with a NaCl gradient. All 4 major caseins were separated, and the purity of each peak was assessed using sodium dodecyl sulfate-PAGE. Purified casein fractions were also added to raw milk to confirm their elution volumes. The quantification was carried out using purified caseins in buffer as well as added directly to fresh skim milk. This method can also be employed to determine the decrease in kappa-casein and the release of the casein-macropeptide during enzymatic hydrolysis using rennet. In this case, the main advantage of using this method is the lack of organic solvents compared with the conventional method for separation of macropeptide (using reversed phase HPLC).

  20. [Comparison of the function and conformation of human β-casein and bovine β-casein by spectroscopic study].

    Science.gov (United States)

    Liu, Wei; Li, Meng; Ren, Hao-wei; Liu, Ning

    2014-12-01

    β-Casein was the main component of human milk casein, but the content of β-casein in the bovine milk was less. The difference in β-casein content of the two samples was one of the reasons why human milk is more digestible than bovine milk. Studying the differences of structure and function in human and bovine milk β-casein can help us develop a new human milk simulated infant formula which will be more suitable for the infant gut. The UV spectrophotometer was used to study the solubility, sulfhydryl and emulsification of human milk β-casein and bovine milk β-casein, Fluorescence spectroscopy and the infrared spectroscopy were used to study the structural characteristics of human milk β-casein and bovine milk β-casein. The two samples shared a similar isoelectric point (pH 4.0~5.0), the solubility of human milk β-casein (10.83%) was lower than which in bovine milk β-casein (11.83%) near the pI, while it was higher when it deviated the pI. The emulsion ability (110~140 m2 · g(-1)) of human milk β-casein was higher than that in bovine milk β-casein (70~130 m2 · g(-1)) and surface sulfhydryl group (SH) of two kinds of milk protein were similar [(18.47±0.08) μmol · g(-1) and (18.67±0.17) μmol · g(-1)]. The total sulfhydryl group [(47.46±0.23) μmol · g(-1)] in bovine milk β-casein was more than that in human milk β-casein [(26.17±0.12) μmol · g(-1)]. Functional groups in two samples were similar and they both contained beta sheet, human milk β-casein had less H-bond and internal hydrophobic than bovine milk β-casein. The results showed that the two samples had similar functional groups, while human milk β-casein had much less secondary structure such as α-helix and β-sheet, a looser tertiary structure and a better interfacial activity.

  1. Casein mediated green synthesis and decoration of reduced graphene oxide.

    Science.gov (United States)

    Maddinedi, Sireesh Babu; Mandal, Badal Kumar; Vankayala, Raviraj; Kalluru, Poliraju; Tammina, Sai Kumar; Kiran Kumar, H A

    2014-05-21

    This research is mainly focusing on one-step biosynthesis of graphene from graphene oxide and its stabilization using naturally occurring milk protein, casein. The synthesis of casein reduced graphene oxide (CRGO) was completed within 7h under reflux at 90°C with the formation of few layered fine graphene nanosheets. UV-Vis, XRD, XPS analysis data revealed the reduction process of the graphene oxide. Results of FT-IR, HPLC and TEM analysis have shown that the ensuing material consists of graphene decorated with casein molecules. Aspartic acid and glutamic acid residue present in casein molecules are responsible for the reduction of graphene oxide.

  2. Casein mediated green synthesis and decoration of reduced graphene oxide

    Science.gov (United States)

    Maddinedi, Sireesh Babu; Mandal, Badal Kumar; Vankayala, Raviraj; Kalluru, Poliraju; Tammina, Sai Kumar; Kiran Kumar, H. A.

    This research is mainly focusing on one-step biosynthesis of graphene from graphene oxide and its stabilization using naturally occurring milk protein, casein. The synthesis of casein reduced graphene oxide (CRGO) was completed within 7 h under reflux at 90 °C with the formation of few layered fine graphene nanosheets. UV-Vis, XRD, XPS analysis data revealed the reduction process of the graphene oxide. Results of FT-IR, HPLC and TEM analysis have shown that the ensuing material consists of graphene decorated with casein molecules. Aspartic acid and glutamic acid residue present in casein molecules are responsible for the reduction of graphene oxide.

  3. Influence of shear during enzymatic gelation of caseinate-water and caseinate-water-fat systems

    NARCIS (Netherlands)

    Manski, J.M.; Goot, van der A.J.; Boom, R.M.

    2007-01-01

    Solidification, emulsification and application of shear were combined to induce diversity and heterogeneity in the micro- and macrostructure of concentrated caseinate-based food matrices containing a dispersed fat phase. The products were evaluated with selected parameters from small-scale and large

  4. Origin of suppressed demixing in casein/xanthan mixtures

    NARCIS (Netherlands)

    van Gruijthuijsen, K.; Herle, V.; Tuinier, R.; Schurtenberger, P.; Stradner, A.

    2012-01-01

    We explore the properties of casein/xanthan mixtures for xanthan concentrations beyond those inducing phase separation. Previous work has successfully described the onset of demixing by depletion theory in the protein limit, where the xanthan polysaccharides, the polymers, are larger than the casein

  5. Is there a feeding strategy to increase milk casein content?

    Directory of Open Access Journals (Sweden)

    A. Formigoni

    2010-04-01

    Full Text Available Because more than 60% of milk produced in Italy is transformed into cheese, milk economical value strongly depends on cheese yield. Among the factors that influence cheese yield, milk casein and fat content plays a major role: when milk is converted into Grana Padano and Parmigiano reggiano, three grams of seasoned cheese are produced from one gram of milk casein.....

  6. Quantification of Melanoidin Concentration in Sugar-Casein Systems

    NARCIS (Netherlands)

    Brands, C.M.J.; Wedzicha, B.L.; Boekel, van M.A.J.S.

    2002-01-01

    Melanoidins are the final, brown, high molecular weight products of the Maillard reaction. The aim of the present study was to determine the average molar extinction coefficients of melanoidins formed in heated glucose-casein and fructose-casein systems. The value of the extinction coefficient can b

  7. Lactoferrin binding to transglutaminase cross-linked casein micelles

    NARCIS (Netherlands)

    Anema, S.G.; de Kruif, C.G.

    2012-01-01

    Casein micelles in skim milk were either untreated (untreated milk) or were cross-linked using transglutaminase (TGA-milk). Added lactoferrin (LF) bound to the casein micelles and followed Langmuir adsorption isotherms. The adsorption level was the same in both milks and decreased the micellar zeta

  8. Phosphorylation of as1-casein is regulated by different genes

    NARCIS (Netherlands)

    Bijl, E.; Valenberg, van H.J.F.; Huppertz, T.; Hooijdonk, van A.C.M.; Bovenhuis, H.

    2014-01-01

    Casein phosphorylation is a posttranslational modification catalyzed by kinase enzymes that attach phosphate groups to specific AA in the protein sequence. This modification is one of the key factors responsible for the stabilization of calcium phosphate nanoclusters in casein micelles and for the i

  9. Physical stability of caseinate stabilized emulsions during heating.

    NARCIS (Netherlands)

    Cruijsen, J.M.M.

    1996-01-01

    The physical stability of caseinate stabilized emulsions was studied during heating (80- 120°C). Coagulation, coalescence and phase separation of the caseinate emulsions was studied using objective heat stability tests. The physical changes were characterized by light microscopy, particle size measu

  10. Water holding capacity and swelling of casein hydrogels

    NARCIS (Netherlands)

    de Kruif, C; Anema, Skelte G.; Zhu, Changjun; Havea, Palatasa; Coker, Christina

    2015-01-01

    The water holding capacity of casein gels was investigated by measuring the swelling and de-swelling under a variety of conditions of temperature and salt concentration. Transglutaminase cross-linked sodium caseinate (15% w/w) gels will swell in good solvents or shrink in poor solvents until an equi

  11. Nucleolin (C23), a physiological substrate for casein kinase II

    DEFF Research Database (Denmark)

    Schneider, H R; Issinger, O G

    1988-01-01

    Nucleolin (C23), a 110 kDa phosphoprotein, which is mainly found in the nucleolus has been shown to be a physiological substrate for casein kinase II (CKII). Nucleolin was identified and characterized by immunodetection using an anti-nucleolin antibody. Phosphopeptide patterns from nucleolin...... phosphorylated by purified casein kinase II and of phosphorylated nucleolin which had been isolated from tumor cells grown in the presence of [32P]-o-phosphate, were identical. The partial tryptic digest revealed nine phosphopeptides. Nucleolin isolated from Krebs II mouse ascites cells was phosphorylated...... by purified casein kinase II with about two moles phosphate per one mole of nucleolin....

  12. Alginate-Casein Microspheres as Bioactive Vehicles for Nutrients

    Institute of Scientific and Technical Information of China (English)

    何志敏; 张茜青; 齐崴; 黄仁亮; 苏荣欣

    2015-01-01

    The aim of this work was to develop an alginate-casein composite microsphere as a bioactive vehicle for oral administration of nutrients by a simple extrusion dripping method. Riboflavin was selected as a model drug, and the microencapsulation efficiency was raised to 97.94%after optimizing the preparation conditions by response surface methodology. In vitro release studies showed that riboflavin was released completely from alginate-casein microspheres in simulated intestinal fluids. Meanwhile, the morphology, structure and interaction between alginate and casein were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectra.

  13. Immune activation by casein dietary antigens in bipolar disorder

    NARCIS (Netherlands)

    Severance, E.G.; Dupont, D.; Dickerson, F.B.; Stallings, C.R.; Origoni, A.E.; Krivogorsky, B.; Yang, S.; Haasnoot, W.; Yolken, R.H.

    2010-01-01

    Objectives: Inflammation and other immune processes are increasingly linked to psychiatric diseases. Antigenic triggers specific to bipolar disorder are not yet defined. We tested whether antibodies to bovine milk caseins were associated with bipolar disorder, and whether patients recognized differe

  14. Examination of rheological properties of aqueous solutions of sodium caseinate

    Directory of Open Access Journals (Sweden)

    Jolanta Gawałek

    2012-12-01

    Full Text Available Application of sodium caseinate as a functional additive in manufacturing processes requires production of its concentrated aqueous solutions which, in industrial conditions, presents a number of difficulties. In order to develop an effective and optimal industrial process of mixing – manufacturing a concentrated solution of sodium caseinate, it is essential to know rheological properties in a definite range of concentrations changing in the course of the dissolving process. The material for investigations was typical commercial sodium caseinate in the form of dry powder manufactured in Poland from acid casein using the method of extrusion. The objective of the undertaken empirical studies was the assessment of the impact of the concentration on rheological properties of sodium caseinate concentrates. Investigations were carried out for five concentrates manufactured in a mixer equipped in a mechanical agitator at concentrations ranging X (% Î (2.5¸12.5 and changing mass proportions of sodium caseinate in the aqueous solution as follows: GS/G (kgS·kg-1 = 0.025. On the basis of the obtained research results, classical flow curves were plotted for individual concentrates. The determined values of viscosity and density of the examined solutions were correlated in the form of h = f(GS/G and r = f(GS/G dependencies which were used during the determination of classical characteristics of mixing forces essential for the assessment of energetic expenditures required to manufacture concentrates in a mixer equipped in a mechanical agitator. The density of the examined concentrates increased in a way directly proportional, while the dynamic viscosity coefficient increased exponentially together with the increase of sodium caseinate concentration. Sodium caseinate concentrates exhibited Newtonian character in the examined range of concentrations.

  15. Na-caseinate/oil/water systems: emulsion morphology diagrams.

    Science.gov (United States)

    Tan, Hui Lin; McGrath, Kathryn M

    2012-09-01

    The concentrated (dispersed phase 50-70 wt%) composition space of Na-caseinate, a family of milk proteins, stabilised emulsions was investigated for three different oils: soybean oil, palm olein and tetradecane with pH 6.8 phosphate buffer continuous phase. The variation of emulsion stability and microstructure were explored using static light scattering, diffusion nuclear magnetic resonance, cryo-scanning electron microscopy, rheology and the time varying macroscopic phase separation of the emulsions. For soybean oil and palm olein a rich diversity of emulsion microstructures and stabilities are realised. Five emulsion domains, each having a different microstructure and macroscopic stability have been identified within the composition space probed. For the lowest concentrations of emulsifier bridging flocculation is evident and emulsions are of low stability. Increasing Na-caseinate concentration leads to an increased stability and the existence of distinct individual oil droplets, visualised using cryo-scanning electron microscopy. Further increases in Na-caseinate concentration reduce emulsion stability due to depletion flocculation. Na-caseinate self-assembly is then initiated. At sufficiently high Na-caseinate and/or oil concentrations the continuous phase of the emulsion is a three-dimensional protein network and emulsion stability is again enhanced. At the limits of the emulsion composition space a gel-like paste is formed. The diversity of emulsion microstructure is reduced when tetradecane is the discrete phase. Na-caseinate self-assembly is limited and there is no evidence for formation of a protein network.

  16. Casein kinase-2 structure-function relationship

    DEFF Research Database (Denmark)

    Boldyreff, B; Meggio, F; Pinna, L A

    1992-01-01

    Nine mutants of human casein kinase-2 beta subunit have been created and assayed for their ability to assemble with the catalytic alpha subunit to give, at a 1:1 molar ratio, a fully competent CK-2 holoenzyme as judged by the following criteria: 1) the generation of an active heterotetrameric form......, consequently, stimulation of activity. This indicates that residue(s) located in the 171-209 sequence is essential for reconstitution. Also a four residue's N-terminal deletion (removing the autophosphorylation site) and single to quintuple substitutions of alanine for the acidic residues clustered in the 55......-70 sequence give rise to mutants that still assemble with the alpha subunit to give a tetrameric holoenzyme. However, in the case of the mutants A57,59, A63,64, A59-61,63,64 in vitro assembly with the CK-2 alpha subunit was not complete. There were also intermediate complexes, free alpha-subunit and beta...

  17. Structural investigations of sodium caseinate micelles in complex environments

    Energy Technology Data Exchange (ETDEWEB)

    Huck Iriart, C.; Herrera, M.L.; Candal, R. [Universidad de Buenos Aires, Buenos Aires (Argentina); Oliveira, C.L.P. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil); Torriani, I. [Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil)

    2012-07-01

    Full text: The most frequent destabilization mechanisms in Sodium Caseinate (NaCas) emulsions are creaming and flocculation. Coarse or fine emulsions with low protein con- tent destabilize mainly by creaming. If migration mechanism is suppressed, flocculation may become the main mechanism of destabilization. Small Angle X-Ray Scattering (SAXS) technique was applied to investigate sodium caseinate micelles structure in different environments. As many natural products, Sodium Caseinate samples have large polydisperse size distribution. The experimental data was analyzed using advanced modeling approaches. The Form Factor for the Caseinate micelle subunits was described by an ellipsoidal core shell model and the structure factor was split into two contributions, one corresponding to the particle-particle interactions and another one for the long range correlation of the subunits in the supramolecular structure. For the first term the hard sphere structure factor using the Percus-Yevick approximation for closure relation was used and for the second term a fractal model was applied. Three concentrations of sodium Caseinate (2, 5 and 7.5 %wt.) were measured in pure water, sugar solutions (20 %wt.) and in three different lipid phase emulsions containing 10 %wt. sunflower seed, olive and fish oils. Data analysis provided an average casein subunit radius of 4 nm, an average distance between the subunits of around 20nm and a fractal dimension value of around 3 for all samples. As indicated by the values of the correlation lengths for the set of studied samples, the casein aggregation is strongly affected by simple sugar additions and it is enhanced by emulsion droplets hydrophobic interaction. As will be presented, these nanoscale structural results provided by scattering experiments is consistent with macroscopic results obtained from several techniques, providing a new understanding of NaCas emulsions. (author)

  18. The role of casein in supporting the operation of surface bound kinesin

    Directory of Open Access Journals (Sweden)

    Hancock William O

    2008-10-01

    Full Text Available Abstract Microtubules and associated motor proteins such as kinesin are envisioned for applications such as bioseparation and molecular sorting to powering hybrid synthetic mechanical devices. One of the challenges in realizing such systems is retaining motor functionality on device surfaces. Kinesin motors adsorbed onto glass surfaces lose their functionality or ability to interact with microtubules if not adsorbed with other supporting proteins. Casein, a milk protein, is commonly used in microtubule motility assays to preserve kinesin functionality. However, the mechanism responsible for this preservation of motor function is unknown. To study casein and kinesin interaction, a series of microtubule motility assays were performed where whole milk casein, or its αs1 and αs2, β or κ subunits, were introduced or omitted at various steps of the motility assay. In addition, a series of epifluorescence and total internal reflection microscopy (TIRF experiments were conducted where fluorescently labeled casein was introduced at various steps of the motility assay to assess casein-casein and casein-glass binding dynamics. From these experiments it is concluded that casein forms a bi-layer which supports the operation of kinesin. The first tightly bound layer of casein mainly performs the function of anchoring the kinesin while the second more loosely bound layer of casein positions the head domain of the kinesin to more optimally interact with microtubules. Studies on individual casein subunits indicate that β casein was most effective in supporting kinesin functionality while κ casein was found to be least effective.

  19. Modulation of mice fecal microbiota by administration of casein glycomacropeptide

    Directory of Open Access Journals (Sweden)

    Qingsen Chen

    2012-12-01

    Full Text Available Casein glycomacropeptide (GMP is known to promote the in vitro growth of Bifidobacteria and Lactobacilli. In this paper, we used conven- tional culture techniques and fluorescent in situ hybridization (FISH techniques to investigate the effect of casein GMP on mice fecal microbiota. The population structure of the intestinal microbiota, including Lactobacillus, Bifidobacteria, Enterococcus, coliforms and Enterobacteriaceae, was tested and compared. After consecutive administration of casein GMP for 15 days, numbers of Lactobacillus and Bifidobacteria increased significantly (P<0.01, numbers of Enterobacteriaceae and Coliforms decreased significantly (P<0.05 while no significant changes were observed for Enterococcus. The detection limits of FISH technique were significantly lower (P<0.01 than the traditional culture method. These results suggested that consumption of casein GMP had a prebiotic effect on male BALB/c mice. Casein GMP helped establish a healthier intestinal microbiota. Additionally, FISH was proved to be a rapid and relatively low-cost detection method that can be used to further our understanding of human intestinal microbiota.

  20. Casein micelles: size distribution in milks from individual cows.

    Science.gov (United States)

    de Kruif, C G Kees; Huppertz, Thom

    2012-05-09

    The size distribution and protein composition of casein micelles in the milk of Holstein-Friesian cows was determined as a function of stage and number of lactations. Protein composition did not vary significantly between the milks of different cows or as a function of lactation stage. Differences in the size and polydispersity of the casein micelles were observed between the milks of different cows, but not as a function of stage of milking or stage of lactation and not even over successive lactations periods. Modal radii varied from 55 to 70 nm, whereas hydrodynamic radii at a scattering angle of 73° (Q² = 350 μm⁻²) varied from 77 to 115 nm and polydispersity varied from 0.27 to 0.41, in a log-normal distribution. Casein micelle size in the milks of individual cows was not correlated with age, milk production, or lactation stage of the cows or fat or protein content of the milk.

  1. Rheology and phase behavior of dense casein micelle dispersions

    Science.gov (United States)

    Bouchoux, A.; Debbou, B.; Gésan-Guiziou, G.; Famelart, M.-H.; Doublier, J.-L.; Cabane, B.

    2009-10-01

    Casein micelle dispersions have been concentrated through osmotic stress and examined through rheological experiments. In conditions where the casein micelles are separated from each other, i.e., below random-close packing, the dispersions have exactly the flow and dynamic properties of the polydisperse hard-sphere fluid, demonstrating that the micelles interact only through excluded volume effects in this regime. These interactions cause the viscosity and the elastic modulus to increase by three orders of magnitude approaching the concentration of random-close packing estimated at Cmax≈178 g/l. Above Cmax, the dispersions progressively turn into "gels" (i.e., soft solids) as C increases, with elastic moduli G' that are nearly frequency independent. In this second regime, the micelles deform and/or deswell as C increases, and the resistance to deformation results from the formation of bonds between micelles combined with the intrinsic mechanical resistance of the micelles. The variation in G' with C is then very similar to that observed with concentrated emulsions where the resistance to deformation originates from a set of membranes that separate the droplets. As in the case of emulsions, the G' values at high frequency are also nearly identical to the osmotic pressures required to compress the casein dispersions. The rheology of sodium caseinate dispersions in which the caseins are not structured into micelles is also reported. Such dispersions have the behavior of associative polymer solutions at all the concentrations investigated, further confirming the importance of structure in determining the rheological properties of casein micelle systems.

  2. Electrochemical immunosensor for the determination of β-casein

    Directory of Open Access Journals (Sweden)

    Judith Molinari

    2015-03-01

    Full Text Available An amperometric biosensor for the quantification of food allergens based on an inhibitory immunoassay is presented. As a proof of concept, the experimental conditions were optimized for the detection of β-casein in the 0-10 ppm range. Eight electro­che­mi­cal cells were integrated into a small-sized portable potentiostat controlled by a smart­phone via Bluetooth communication. The determination of β-casein in eight different samples can be measured with the electrochemical biosensor, which has the potential to be modified for the detection of multiple allergens.

  3. Expression of casein kinase 2 during mouse embryogenesis

    DEFF Research Database (Denmark)

    Mestres, P; Boldyreff, B; Ebensperger, C;

    1994-01-01

    This paper deals with the expression and distribution of casein kinase 2 (CK-2) subunits in mouse embryos at different developmental stages. Expression was investigated at the mRNA level of CK-2 alpha- and beta-subunits by in situ hybridization and distribution at the protein level by immunohisto......This paper deals with the expression and distribution of casein kinase 2 (CK-2) subunits in mouse embryos at different developmental stages. Expression was investigated at the mRNA level of CK-2 alpha- and beta-subunits by in situ hybridization and distribution at the protein level...

  4. Horseradish peroxidase-catalyzed cross-linking of feruloylated arabinoxylans with β-casein

    NARCIS (Netherlands)

    Boeriu, C.G.; Oudgenoeg, G.; Spekking, W.T.J.; Berendsen, L.B.J.M.; Vancon, L.; Boumans, H.; Gruppen, H.; Berkel, W.J.H. van; Laane, C.; Voragen, A.G.J.

    2004-01-01

    Heterologous conjugates of wheat arabinoxylan and β-casein were prepared via enzymatic cross-linking, using sequential addition of the arabinoxylan to a mixture of β-casein, peroxidase, and hydrogen peroxide. The maximal formation of adducts between the β-casein and the feruloylated arabinoxylan was

  5. Purification and properties of a ribosomal casein kinase from rabbit reticulocytes

    DEFF Research Database (Denmark)

    Issinger, O G

    1977-01-01

    suggested that the casein kinase is a dimer composed of subunits of identical molecular weight. The enzyme utilizes GTP as well as ATP as a phosphoryl donor. It preferentially phosphorylates acidic proteins, in particular the model substrates casein and phosvitin. Casein kinase is cyclic AMP...

  6. Indirect and direct determination of the casein content of milk by Kjeldahl nitrogen analysis: collaborative study.

    Science.gov (United States)

    Lynch, J M; Barbano, D M; Fleming, J R

    1998-01-01

    The classic method for determination of milk casein is based on precipitation of casein at pH 4.6. Precipitated milk casein is removed by filtration and the nitrogen content of either the precipitate (direct casein method) or filtrate (noncasein nitrogen; NCN) is determined by Kjeldahl analysis. For the indirect casein method, milk total nitrogen (TN; Method 991.20) is also determined and casein is calculated as TN minus NCN. Ten laboratories tested 9 pairs of blind duplicate raw milk materials with a casein range of 2.42-3.05% by both the direct and indirect casein methods. Statistical performance expressed in protein equivalents (nitrogen x 6.38) with invalid and outlier data removed was as follows: NCN method (wt%), mean = 0.762, sr = 0.010, sR = 0.016, repeatability relative standard deviation (RSDr) = 1.287%, reproducibility relative standard deviation (RSDr) = 2.146%; indirect casein method (wt%), mean = 2.585, repeatability = 0.015, reproducibility = 0.022, RSDr = 0.560%, RSDR = 0.841; direct casein method (wt%), mean = 2.575, sr = 0.015, sR = 0.025, RSDr = 0.597%, RSDR = 0.988%. Method performance was acceptable and comparable to similar Kjeldahl methods for determining nitrogen content of milk (Methods 991.20, 991.21, 991.22, 991.23). The direct casein, indirect casein, and noncasein nitrogen methods have been adopted by AOAC INTERNATIONAL.

  7. Casein Micelles: Size Distribution in Milks from Individual Cows

    NARCIS (Netherlands)

    de Kruif, C.G.; Huppertz, T.

    2012-01-01

    The size distribution and protein composition of casein micelles in the milk of Holstein-Friesian cows was determined as a function of stage and number of lactations. Protein composition did not vary significantly between the milks of different cows or as a function of lactation stage. Differences i

  8. Enhanced casein kinase II activity in human tumour cell cultures

    DEFF Research Database (Denmark)

    Prowald, K; Fischer, H; Issinger, O G

    1984-01-01

    Casein kinase II (CKII) activity is enhanced as much as 2-3 fold in established and 4-5-fold in transformed human cell lines when compared to that of fibroblasts and primary human tumour cell cultures where CKII activity never exceeded a basic level. The high activity of CKII in transformed cells...

  9. Modification of Casein%酪素的改性

    Institute of Scientific and Technical Information of China (English)

    杨秦欢

    2013-01-01

    In this paper, the structure, characteristics, modification methods and application of casein are summarized. It is hoped that this can be helpful to related researchers.%  综述了酪素的结构、特性、改性方法和用途,希望能作为相关科技工作者的参考。

  10. Pressure-Aided Proteolysis of ß-Casein

    NARCIS (Netherlands)

    Bruins, M.E.; Creusot, N.P.; Gruppen, H.; Janssen, A.E.M.; Boom, R.M.

    2009-01-01

    ß-Casein, which is present in the form of micelles at atmospheric pressure, has been hydrolyzed during pressure treatment to improve the accessibility of the protein. Two proteolytic enzymes with different specificities were used. Trypsin was aimed at mainly hydrolyzing hydrophilic segments of ß-cas

  11. Modification of Casein by the Lipid Oxidation Product Malondialdehyde

    NARCIS (Netherlands)

    Adams, A.; Kimpe, de N.; Boekel, van T.

    2008-01-01

    The reaction of malondialdehyde with casein was studied in aqueous solution to evaluate the impact of this lipid oxidation product on food protein modification. By using multiresponse modeling, a kinetic model was developed for this reaction. The influence of temperature and pH on protein browning a

  12. Short communication: casein haplotype variability in sicilian dairy goat breeds.

    Science.gov (United States)

    Gigli, I; Maizon, D O; Riggio, V; Sardina, M T; Portolano, B

    2008-09-01

    In the Mediterranean region, goat milk production is an important economic activity. In the present study, 4 casein genes were genotyped in 5 Sicilian goat breeds to 1) identify casein haplotypes present in the Argentata dell'Etna, Girgentana, Messinese, Derivata di Siria, and Maltese goat breeds; and 2) describe the structure of the Sicilian goat breeds based on casein haplotypes and allele frequencies. In a sample of 540 dairy goats, 67 different haplotypes with frequency >or=0.01 and 27 with frequency >or=0.03 were observed. The most common CSN1S1-CSN2-CSN1S2-CSN3 haplotype for Derivata di Siria and Maltese was FCFB (0.17 and 0.22, respectively), whereas for Argentata dell'Etna, Girgentana and Messinese was ACAB (0.06, 0.23, and 0.10, respectively). According to the haplotype reconstruction, Argentata dell'Etna, Girgentana, and Messinese breeds presented the most favorable haplotype for cheese production, because the casein concentration in milk of these breeds might be greater than that in Derivata di Siria and Maltese breeds. Based on a cluster analysis, the breeds formed 2 main groups: Derivata di Siria, and Maltese in one group, and Argentata dell'Etna and Messinese in the other; the Girgentana breed was between these groups but closer to the latter.

  13. On studying protein phosphorylation patterns using bottom-up LC-MS/MS: the case of human alpha-casein

    DEFF Research Database (Denmark)

    Kjeldsen, Frank; Savitski, Mikhail M; Nielsen, Michael L

    2007-01-01

    minerals to the new-born. Human alpha(s1)-casein has been reported to be much less phosphorylated than ruminant caseins, which may indicate a different function of caseins in humans. Revealing the phosphorylation pattern in human casein can thus shed light on its function. The current study found...

  14. Quantitative determination of casein genetic variants in goat milk: Application in Girgentana dairy goat breed.

    Science.gov (United States)

    Montalbano, Maria; Segreto, Roberta; Di Gerlando, Rosalia; Mastrangelo, Salvatore; Sardina, Maria Teresa

    2016-02-01

    The study was conducted to develop a high-performance liquid chromatographic (HPLC) method to quantify casein genetic variants (αs2-, β-, and κ-casein) in milk of homozygous individuals of Girgentana goat breed. For calibration experiments, pure genetic variants were extracted from individual milk samples of animals with known genotypes. The described HPLC approach was precise, accurate and highly suitable for quantification of goat casein genetic variants of homozygous individuals. The amount of each casein per allele was: αs2-casein A = 2.9 ± 0.8 g/L and F = 1.8 ± 0.4 g/L; β-casein C = 3.0 ± 0.8 g/L and C1 = 2.0 ± 0.7 g/L and κ-casein A = 1.6 ± 0.3 g/L and B = 1.1 ± 0.2 g/L. A good correlation was found between the quantities of αs2-casein genetic variants A and F, and β-casein C and C1 with other previously described method. The main important result was obtained for κ-casein because, till now, no data were available on quantification of single genetic variants for this protein.

  15. Digestibility of transglutaminase cross-linked caseinate versus native caseinate in an in vitro multicompartmental model simulating young child and adult gastrointestinal conditions

    NARCIS (Netherlands)

    Havenaar, R.; Jong, A. de; Koenen, M.E.; Bilsen, J. van; Janssen, A.M.; Labij, E.; Westerbeek, H.J.M.

    2013-01-01

    Aim of this study was to investigate the digestion of transglutaminase cross-linked caseinate (XLC) versus native caseinate (NC) in solution and in cheese spread under digestive conditions for adults and children mimicked in a gastrointestinal model. Samples were collected for gel electrophoresis an

  16. Characterization of the Casein/Keratin Self-Assembly Nanomicelles

    Directory of Open Access Journals (Sweden)

    Su Xiao-Zhou

    2014-01-01

    Full Text Available Complex nanomicelles were made from casein and keratin through electrostatic self-assembly and transglutaminase fixation that was proved to be harmless and green. The complex nanomicelles were characterized by dynamic light scattering, scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and steady-state florescence. The results show that the complex nanomcelles acquired at the neutral pH in the mass ratio of casein to keratin 4 : 1 exhibit an anomalous sphere shape with uniform size which the diameter is about 40–70 nm. The complex nanomicelles in solution possess excellent dilution and storage stability due to the fixation and their high ζ-potential (22.8 mV. The complex nanomicelles are relatively hydrophilic and have a good potential for industrial application.

  17. Geographic distribution of haplotype diversity at the bovine casein locus

    Directory of Open Access Journals (Sweden)

    Moazami-Goudarzi Katy

    2004-03-01

    Full Text Available Abstract The genetic diversity of the casein locus in cattle was studied on the basis of haplotype analysis. Consideration of recently described genetic variants of the casein genes which to date have not been the subject of diversity studies, allowed the identification of new haplotypes. Genotyping of 30 cattle breeds from four continents revealed a geographically associated distribution of haplotypes, mainly defined by frequencies of alleles at CSN1S1 and CSN3. The genetic diversity within taurine breeds in Europe was found to decrease significantly from the south to the north and from the east to the west. Such geographic patterns of cattle genetic variation at the casein locus may be a result of the domestication process of modern cattle as well as geographically differentiated natural or artificial selection. The comparison of African Bos taurus and Bos indicus breeds allowed the identification of several Bos indicus specific haplotypes (CSN1S1*C-CSN2*A2-CSN3*AI/CSN3*H that are not found in pure taurine breeds. The occurrence of such haplotypes in southern European breeds also suggests that an introgression of indicine genes into taurine breeds could have contributed to the distribution of the genetic variation observed.

  18. Gluten- and casein-free diets for autistic spectrum disorder

    Science.gov (United States)

    Millward, Claire; Ferriter, Michael; Calver, Sarah J; Connell-Jones, Graham G

    2014-01-01

    Background It has been suggested that peptides from gluten and casein may have a role in the origins of autism and that the physiology and psychology of autism might be explained by excessive opioid activity linked to these peptides. Research has reported abnormal levels of peptides in the urine and cerebrospinal fluid of people with autism. Objectives To determine the efficacy of gluten and/or casein free diets as an intervention to improve behaviour, cognitive and social functioning in individuals with autism. Search methods The following electronic databases were searched: CENTRAL(The Cochrane Library Issue 2, 2007), MEDLINE (1966 to April 2007), PsycINFO (1971 to April 2007), EMBASE (1974 to April 2007), CINAHL (1982 to April 2007), ERIC (1965 to 2007), LILACS (1982 to April 2007), and the National Research register 2007 (Issue1). Review bibliographies were also examined to identify potential trials. Selection criteria All randomised controlled trials (RCT) involving programmes which eliminated gluten, casein or both gluten and casein from the diets of individuals diagnosed with an autistic spectrum disorder. Data collection and analysis Abstracts of studies identified in searches of electronic databases were assessed to determine inclusion by two independent authors The included trials did not share common outcome measures and therefore no meta-analysis was possible. Data are presented in narrative form. Main results Two small RCTs were identified (n = 35). No meta-analysis was possible. There were only three significant treatment effects in favour of the diet intervention: overall autistic traits, mean difference (MD) = −5.60 (95% CI −9.02 to −2.18), z = 3.21, p=0.001 (Knivsberg 2002) ; social isolation, MD = −3.20 (95% CI −5.20 to 1.20), z = 3.14, p = 0.002) and overall ability to communicate and interact, MD = 1.70 (95% CI 0.50 to 2.90), z = 2.77, p = 0.006) (Knivsberg 2003). In addition three outcomes showed no significant difference between the

  19. Characterization of casein and alpha lactalbumin of African elephant (Loxodonta africana) milk.

    Science.gov (United States)

    Madende, M; Osthoff, G; Patterton, H-G; Patterton, H E; Martin, P; Opperman, D J

    2015-12-01

    The current research reports partial characterization of the caseins and α-lactalbumin (α-LA) of the African elephant with proposed unique structure-function properties. Extensive research has been carried out to understand the structure of the casein micelles. Crystallographic structure elucidation of caseins and casein micelles is not possible. Consequently, several models have been developed in an effort to describe the casein micelle, specifically of cow milk. Here we report the characterization of African elephant milk caseins. The κ-caseins and β-caseins were investigated, and their relative ratio was found to be approximately 1:8.5, whereas α-caseins were not detected. The gene sequence of β-casein in the NCBI database was revisited, and a different sequence in the N-terminal region is proposed. Amino acid sequence alignment and hydropathy plots showed that the κ-casein of African elephant milk is similar to that of other mammals, whereas the β-casein is similar to the human protein, and displayed a section of unique AA composition and additional hydrophilic regions compared with bovine caseins. Elephant milk is destabilized by 62% alcohol, and it is speculated that the β-casein characteristics may allow maintenance of the colloidal nature of the casein micelle, a role that was previously only associated with κ-casein. The oligosaccharide content of milk was reported to be low in dairy animals but high in some other species such as humans and elephants. In the milk of the African elephant, lactose and oligosaccharides both occur at high levels. These levels are typically related to the content of α-LA in the mammary gland and thus point to a specialized carbohydrate synthesis, where the whey protein α-LA plays a role. We report the characterization of African elephant α-LA. Homology modeling of the α-LA showed that it is structurally similar to crystal structures of other mammalian species, which in turn may be an indication that its functional

  20. Polymorphism of caprine milk alphas1-casein in relation to performance of four Polish goat breeds.

    Science.gov (United States)

    Barłowska, J; Litwińczuk, Z; Kedzierska-Matysek, M; Litwińczuk, A

    2007-01-01

    Polymorphism of goat milk alphas1-casein was determined and potential relations between genetic variants of this protein fraction and goat performance were evaluated. The investigations were performed on 598 goats assigned to of 4 breed groups (White improved 254 units, Coloured improved--124, White non-improved--146 and Coloured non-improved--74). For each goat, alphas1-casein polymorphism was determined in polyacrylamide gel by the PAGE-SDS method and percentage of milk alphas1-casein and gene frequency established. There was evaluated goat performance at successive lactations. In the goat population investigated, AA, AB, BB, AE, BE and EE alphas1-casein genotypes were identified. In all four breeds, alphas1-casein genotype EE clearly predominated (27.2-39.2%), recognized as "medium" and its share was higher in the groups of non-improved goats. It was conditioned by high frequency of gene E alphas1-casein (0.419-0.622). Generally, EE genotype percentage was higher in the non-improved goat groups. The improved goats, though, obtained higher productivity in each of the lactation studied. Analysis of relationships between alphas1-casein genetic variants and goats performance confirmed a significant influence on milk, protein and fat yields only in the Coloured improved goat group. There was revealed a more general tendency indicating a significant impact of "strong" alphas1-casein genotypes on a concentration of basic milk components, i.e. fat and protein, especially casein. In a group of goats producing milk of the highest casein content (over 2.4%) and protein (over 3.0%), the animals showing "strong" alphas1-casein variants dominated (85 and 70 %).

  1. A DIGITAL TOOL FOR CASEIN ISOLECTRIC POINT DETERMINATION

    Directory of Open Access Journals (Sweden)

    V. M.T. Trindade

    2015-08-01

    Full Text Available Introduction: Casein is a milk protein that has the same number of positive and negative charges in a pH around 4.7. This characteristic is called the isoelectric point (pI. The pI varies from protein to protein and it depends on the charges of the lateral chain of the constituent aminoacids. At this pH value the protein has its minimum solubility since the net charge is zero and the repulsion between molecules is decreased. Furthermore, the electrostatic interaction occurs between the protein molecules. Thus, they form clumps which tend to precipitate. On the other hand, when they are placed in a solution whose pH is above or below of its pI, the protein molecules have respectively a negative or positive net charge, with strong repulsion between themselves and great interaction with the solvent (water. Objective: This learning object presents a simulation of a laboratory practice for the determination of casein isoelectric point. Materials and Methods: Cartoons were planned in order to show the methodology procedures and biochemical fundamentals. Animations were developed with the aid of the Adobe ® Flash 8 software associated with logic programming. Results: The simulation consists of six steps that reproduce the activities performed in the laboratory. Among them, the user can observe different degrees of turbidity and / or precipitation of casein in solutions with different pH values, he can measure these values with paper indicator strips and then determine the pI of this protein. Conclusions: This learning object was tested by students of Biochemistry I, Pharmacy course since 2012/2. The navigation features, design, interaction, interactivity were considered excellent by 80% of students indicating that this object can be used as an interesting tool to assist the teaching and learning of basic biochemistry.  Available at:www.ufrgs.br/gcoeb/PontoIsoleletricoDaCaseina/PontoIsoleletricoDaCaseina.swf

  2. A DIGITAL TOOL FOR CASEIN ISOLECTRIC POINT DETERMINATION

    OpenAIRE

    V.M.T. Trindade; Santos, I. B.; Zanatta,G.; P. R. Arantes; Salbego, C. G.

    2015-01-01

    Introduction: Casein is a milk protein that has the same number of positive and negative charges in a pH around 4.7. This characteristic is called the isoelectric point (pI). The pI varies from protein to protein and it depends on the charges of the lateral chain of the constituent aminoacids. At this pH value the protein has its minimum solubility since the net charge is zero and the repulsion between molecules is decreased. Furthermore, the electrostatic interaction occurs between the prote...

  3. Monitoring the aggregation of single casein micelles using fluorescence microscopy

    DEFF Research Database (Denmark)

    Bomholt, Julie; Moth-Poulsen, Kasper; Harboe, Marianne

    2011-01-01

    The aggregation of casein micelles (CMs) induced by milk-clotting enzymes is a process of fundamental importance in the dairy industry for cheese production; however, it is not well characterized on the nanoscale. Here we enabled the monitoring of the kinetics of aggregation between single CMs (30......, suggesting significant differences in their composition or structure. Detailed size histograms of CMs during aggregation also revealed the presence of two distinct subpopulations with different growth amplitudes and kinetics. The dependence of these distinct nanoscale processes/parameters on aggregation...

  4. DNA polymorphism at the casein loci in sheep.

    Science.gov (United States)

    Di Gregorio, P; Rando, A; Pieragostini, E; Masina, P

    1991-01-01

    By using seven endonucleases and four bovine cDNA probes specific for alpha S1-, alpha S2-, beta-, and kappa-casein genes, nine restriction fragment length polymorphisms (RFLPs) have been found in the sheep orthologous DNA regions. In contrast to the low level of variation observed at the protein level, these DNA polymorphisms determine a high level of heterozygosity and, therefore, represent useful tools for genetic analyses since they can also be obtained without the need for gene expression. In fact, informative matings suggest that in sheep, as in cattle, the four loci are linked.

  5. Subunit and whole molecule specificity of the anti-bovine casein immune response in recent onset psychosis and schizophrenia

    NARCIS (Netherlands)

    Severance, E.G.; Dickerson, F.B.; Halling, M.; Krivogorsky, B.; Haile, L.; Yang, S.; Stallings, C.R.; Origoni, A.E.; Bossis, I.; Xiao, J.; Dupont, D.; Haasnoot, W.; Yolken, R.H.

    2010-01-01

    Previous studies show increased antibody levels to bovine casein in some individuals with schizophrenia. The immunogenicity of specific domains of bovine casein varies among people with milk sensitivities and thus could vary among different neuropsychiatric disorders. Using ELISAs and immunoblotting

  6. Lipoprotein(a) and dietary proteins: casein lowers lipoprotein(a) concentrations as compared with soy protein1-3

    DEFF Research Database (Denmark)

    Nilausen, Karin Johanne; Meinertz, H.

    1999-01-01

    Lipoprotein(a), plasma lipoproteins, dietary proteins, soy protein, casein, liquid-formula, coronary artery disease, men, Denmark......Lipoprotein(a), plasma lipoproteins, dietary proteins, soy protein, casein, liquid-formula, coronary artery disease, men, Denmark...

  7. Foams and surface rheological properties of b-casein, gliadin and glycinin

    NARCIS (Netherlands)

    Bos, M.A.; Dunnewind, B.; Vliet, van T.

    2003-01-01

    Interfacial rheological properties and their suitability for foam production and stability of two vegetable proteins were studied and compared to ß-casein. Proteins used ranged from flexible to rigid/globular in the order of ß-casein, gliadin and soy glycinin. Experiments were performed at pH 6.7. N

  8. Behaviour of casein micelles at conditions comparable to those in ice cream

    NARCIS (Netherlands)

    Jonkman, M.J.

    2000-01-01

    The physical properties of ice cream are mainly determined by the processing and the ingredients. Milk (powder) is one of the ingredients and ice cream thus contains casein, the major milk protein. A large proportion of casein in ice cream is present in the plasma phase of ice cream. Since the behav

  9. Foams and surface rheological properties of β-casein, gliadin and glycinin

    NARCIS (Netherlands)

    Bos, M.A.; Dunnewind, B.; Vliet, T. van

    2003-01-01

    Interfacial rheological properties and their suitability for foam production and stability of two vegetable proteins were studied and compared to β-casein. Proteins used ranged from flexible to rigid/globular in the order of β-casein, gliadin and soy glycinin. Experiments were performed at pH 6.7. N

  10. The association of low-molecular-weight hydrophobic compounds with native casein micelles in bovine milk.

    Science.gov (United States)

    Cheema, M; Mohan, M S; Campagna, S R; Jurat-Fuentes, J L; Harte, F M

    2015-08-01

    The agreed biological function of the casein micelles in milk is to carry minerals (calcium, magnesium, and phosphorus) from mother to young along with amino acids for growth and development. Recently, native and modified casein micelles were used as encapsulating and delivery agents for various hydrophobic low-molecular-weight probes. The ability of modified casein micelles to bind certain probes may derive from the binding affinity of native casein micelles. Hence, a study with milk from single cows was conducted to further elucidate the association of hydrophobic molecules into native casein micelles and further understand their biological function. Hydrophobic and hydrophilic extraction followed by ultraperformance liquid chromatography-high resolution mass spectrometry analysis were performed over protein fractions obtained from size exclusion fractionation of raw skim milk. Hydrophobic compounds, including phosphatidylcholine, lyso-phosphatidylcholine, phosphatidylethanolamine, and sphingomyelin, showed strong association exclusively to casein micelles as compared with whey proteins, whereas hydrophilic compounds did not display any preference for their association among milk proteins. Further analysis using liquid chromatography-tandem mass spectrometry detected 42 compounds associated solely with the casein-micelles fraction. Mass fragments in tandem mass spectrometry identified 4 of these compounds as phosphatidylcholine with fatty acid composition of 16:0/18:1, 14:0/16:0, 16:0/16:0, and 18:1/18:0. These results support that transporting low-molecular-weight hydrophobic molecules is also a biological function of the casein micelles in milk.

  11. Proteomic analysis and cross species comparison of casein fractions from the milk of dairy animals

    Science.gov (United States)

    Wang, Xiaxia; Zhao, Xiaowei; Huang, Dongwei; Pan, Xiaocheng; Qi, Yunxia; Yang, Yongxin; Zhao, Huiling; Cheng, Guanglong

    2017-01-01

    Casein micelles contribute to the physicochemical properties of milk and may also influence its functionality. At present, however, there is an incomplete understanding of the casein micelle associated proteins and its diversity among the milk obtained from different species. Therefore, milk samples were collected from seven dairy animals groups, casein fractions were prepared by ultracentrifugation and their constituent proteins were identified by liquid chromatography tandem mass spectrometry. A total of 193 distinct proteins were identified among all the casein micelle preparations. Protein interaction analysis indicated that caseins could interact with major whey proteins, including β-lactoglobulin, α-lactalbumin, lactoferrin, and serum albumin, and then whey proteins interacted with other proteins. Pathway analysis found that the peroxisome proliferator-activated receptor signaling pathway is shared among the studied animals. Additionally, galactose metabolism pathway is also found to be commonly involved for proteins derived from camel and horse milk. According to the similarity of casein micelle proteomes, two major sample clusters were classified into ruminant animals (Holstein and Jersey cows, buffaloes, yaks, and goats) and non-ruminants (camels and horses). Our results provide new insights into the protein profile associated with casein micelles and the functionality of the casein micelle from the studied animals. PMID:28240229

  12. Categorization of rheological scaling models for particle gels applied to casein gels

    NARCIS (Netherlands)

    Mellema, M.; Opheusden, van J.H.J.; Vliet, van T.

    2002-01-01

    Rennet-induced casein gels made from skim milk were studied rheologically. A scaling model or framework for describing the rheological behavior of gels is discussed and used for classification of the structure of casein gels. There are two main parameters in the model that describe the number of def

  13. Effect of boiling on the antidiabetic property of enzyme treated sheep milk casein

    Directory of Open Access Journals (Sweden)

    Farhath Jan

    2016-10-01

    Full Text Available Aim: Sheep milk-born bioactive peptides have been found to exhibit various physiological activities. The present work was designed with the aim to evaluate the effect of boiling on antidiabetic property of peptides derived from sheep milk caseinate on hydrolysis with three different proteases. Materials and Methods: In this investigation, casein prepared from raw and boiled sheep milk was hydrolyzed by three commercially available proteases (trypsin, pepsin, and chymotrypsin. These hydrolysates collected at different hydrolysis times (60, 120, 160, and 240 min were assayed for their antidiabetic activity. Results: Among the three different enzyme hydrolysates, casein treated with chymotrypsin shows the highest antidiabetic activity among other enzymes. While the antidiabetic effect of raw milk-derived casein hydrolysates always exceeds than effect shown by boiled milk casein hydrolysates. Conclusion: The result obtained hence shows that the effect of boiling on the properties of bioactive peptides released during different enzyme digestion depends largely on the enzymatic formulation used and treatment conditions. Chymotrypsin treatment of raw casein yields peptides with maximum antidiabetic activity as compared to pepsin and trypsin. Moreover, the peptides produced after enzymatic treatment of boiled casein show reduced antidiabetic properties. Therefore, enzymatically treated raw milk casein hydrolysates may be used as effective nutritional supplements for diabetic patients, as it causes a significant inhibition of α-amylase activity.

  14. Bioavailability of lysine for kittens in overheated casein is underestimated by the rat growth assay method.

    Science.gov (United States)

    Larsen, J A; Fascetti, A J; Calvert, C C; Rogers, Q R

    2010-10-01

    Growth assays were performed to determine lysine bioavailability for kittens and rats in untreated and heated casein; these values were compared with estimates obtained with an in vitro method. Body weight, food intake, nitrogen and dry matter digestibility, and plasma lysine were determined during an 80-day growth trial using kittens (n = 16). Body weight and food intake were determined during a 21-day growth trial using weanling rats (n = 80). The growth data showed bioavailable lysine to be 102.4% and 100.2% (for untreated casein) and 66.1% and 51.7% (for heated casein) for kittens and rats, respectively. There was no relationship between plasma lysine and dietary lysine concentrations for kittens. There were no significant differences in nitrogen or dry matter digestibility among diets for kittens. The chemically reactive lysine content of untreated casein was 99.6%, and of heated casein was 67.1%. Heat treatment of casein resulted in significantly decreased lysine bioavailability as estimated by all methods. For untreated casein, both growth assays showed good agreement with the in vitro method for available lysine. For heated casein, the rat growth assay significantly underestimated bioavailable lysine as determined in kittens while the in vitro method closely approximated this value for the cat.

  15. Orthokinetic flocculation of caseinate-stabilized emulsions : influence of calcium concentration, shear rate and protein content

    NARCIS (Netherlands)

    Schokker, E.P.; Dalgleish, D.G.

    2000-01-01

    Calcium-induced flocculation of caseinate-stabilized soybean oil-in- water emulsions in conditions of Couette flow was studied. A concentrated emulsion (20% oil, 0.5-2.0% sodium caseinate in 20 mM imidazole, pH 7) was diluted 20 times in buffer containing concentrations of CaCl2 between 9 and 17 mM

  16. Antimutagenic activity of casein against MNNG in the E. coli DNA repair host-mediated assay.

    NARCIS (Netherlands)

    Boekel, van M.A.J.S.; Goeptar, A.R.; Alink, G.M.

    1997-01-01

    The effect of caseinate and soy protein in the diet on the mutagenicity induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was assessed in-vivo and ex-vivo in the DNA-repair host-mediated assay and liquid suspension assay, respectively. Of the two proteins only casein showed a strong antimutagen

  17. Bovine Chymosin: A Computational Study of Recognition and Binding of Bovine κ-Casein

    DEFF Research Database (Denmark)

    Palmer, David S.; Christensen, Anders Uhrenholt; Sørensen, Jesper

    2010-01-01

    Bovine chymosin is an aspartic protease that selectively cleaves the milk protein κ-casein. The enzyme is widely used to promote milk clotting in cheese manufacturing. We have developed models of residues 97-112 of bovine κ-casein complexed with bovine chymosin, using ligand docking, conformational...

  18. Casein haplotypes and their association with milk production traits in the Finnish Ayrshire cattle.

    Science.gov (United States)

    Velmala, R; Vilkki, J; Elo, K; Mäki-Tanila, A

    1995-12-01

    Polymorphism of casein genes was studied in half-sib families of artificial insemination bulls of the Finnish Ayrshire dairy breed. Ten grandsires and 300 of their sons were genotyped for the following polymorphisms: alpha s1-casein (B, C), beta-casein (A1, A2), the microsatellite within the kappa-casein gene (ms5, ms4) and kappa-casein (A, B, E). Nine different combinations of these alleles, casein haplotypes, were found. Associations between casein haplotypes and milk production traits (milk and protein yield, fat and protein percentage and milking speed) were studied with ordinary least-squares analysis to find a direct effect of the haplotypes or an association within individual grandsire families using the granddaughter design. Estimated breeding values of sons were obtained from cow evaluation by animal model. No direct effect of the casein haplotypes on the traits was found. Within grandsire families, in one out of four families the chromosomal segment characterized by haplotype 3 (B-A2-ms4-A) was associated with an increase in milk yield (P < 0.01) and a decrease in fat percentage (P < 0.01) when contrasted with haplotype 8 (B-A1-ms4-E). The results provide evidence that in the Finnish Ayrshire breed at least one quantitative trait locus affecting the genetic variation in yields traits is segregating linked to either haplotype 3 (B-A2-ms4-A) or 8 (B-A1-ms4-E).

  19. Correlations between biochemical characteristics and foam-forming and -stabilizing ability of whey and casein hydrolysates

    NARCIS (Netherlands)

    Ven, van der C.; Bont, D.B.A.; Voragen, A.G.J.

    2002-01-01

    Whey protein and casein were hydrolyzed with 11 commercially available enzymes. Foam properties of 44 samples were measured and were related to biochemical properties of the hydrolysates using statistical data analysis. All casein hydrolysates formed high initial foam levels, whereas whey hydrolysat

  20. Dissolution and enzymatic hydrolysis of casein micelles studied by dynamic light scattering

    Institute of Scientific and Technical Information of China (English)

    LIU Rui; QI Wei; SU Rongxin; ZHANG Yubin; JIN Fengmin; HE Zhimin

    2007-01-01

    The effects of temperature,ionic strength,and enzymatic hydrolysis on the average hydrodynamic radius (Rh) of casein micelles in phosphate buffer were studied by using dynamic light scattering.The results showed that the average Rh value of casein mieelles decreased irreversibly during the heating,decreased with the increase of ionic strength in lower ionic strength solution (less than 0.05 tool/L),but opposite in higher ionic strength solution (above 0.1 tool/L).The Rh value of casein increased rapidly during the process of enzymatic hydrolysis,and the structural model of casein micelles in the enzymatic hydrolysis process was also proposed,i.e.the casein micelle changed from compact sphere into unfolded and regularly flocky peptides.

  1. Correlations between biochemical characteristics and foam-forming and -stabilizing ability of whey and casein hydrolysates.

    Science.gov (United States)

    van der Ven, Cornelly; Gruppen, Harry; de Bont, Dries B A; Voragen, Alphons G J

    2002-05-08

    Whey protein and casein were hydrolyzed with 11 commercially available enzymes. Foam properties of 44 samples were measured and were related to biochemical properties of the hydrolysates using statistical data analysis. All casein hydrolysates formed high initial foam levels, whereas whey hydrolysates differed in their foam-forming abilities. Regression analysis using the molecular weight distribution of whey hydrolysates as predictors showed that the hydrolysate fraction containing peptides of 3-5 kDa was most strongly related to foam formation. Foam stability of whey hydrolysates and of most casein hydrolysates was inferior to that of the intact proteins. The foam stability of casein hydrolysate foams was correlated to the molecular weight distribution of the hydrolysates; a high proportion of peptides >7 kDa, composed of both intact casein and high molecular weight peptides, was positively related to foam stability.

  2. Compound exocytosis of casein micelles in mammary epithelial cells.

    Science.gov (United States)

    Dylewski, D P; Keenan, T W

    1983-07-01

    Ultrastructure of lactating bovine and rat mammary epithelial cells was studied with emphasis on secretory vesicle interactions. In the apical zone of the cell, adjacent secretory vesicles formed ball and socket configurations at their points of apposition. Similar configurations were formed between plasma membrane and secretory vesicle membrane. These structures may be formed by the diffusion of water between vesicles with different osmotic potentials. Frequently, vesicular chains consisting of 10 or more linked secretory vesicles were observed. Prior to the exocytotic release of casein micelles, adjacent vesicles fused through fragmentation of the ball and socket membrane. These membrane fragments and the casein micelles appeared to be secreted into the alveolar lumen after passing from one vesicle into another and finally through a pore in the apical plasma membrane. Emptied vesicular chains appeared to collapse and fragmentation of their membrane was observed. Based on these observations, we suggest that most vesicular membrane does not directly contact or become incorporated into the plasma membrane during secretion of the nonfat phase of milk.

  3. Preparation of Ultra-High-Speed Casein Trade Mark Adhesive

    Institute of Scientific and Technical Information of China (English)

    Xiong-Zhi Wu; Yu-Jiao Li

    2005-01-01

    @@ 1Introduction In present trade mark adhesives for beer bottle labeling are mostly prepared based on starch[1] ,polyvinyl formal[2] and their derivants[3-5] ,but they can only be applied to the labeling speed of 20 000 bottle/h and their water proofness are not satisfactory, especially when the water temperature is 0℃ below. The application of metal foil requires that sealing and labeling must be finished at the same time, but different penetrating speed of water in metal foil and paper label causes different drying speed, and also, the labeling speed and need of iced beer are increasing now, so these changes result in more strict requirements for adhesive.In this paper the chelating casein adhesive was obtained with casein as main moldings, urea as dispersing agent, starch as auxiliary, and ZnSO4 as cross-linked agent. The effects of dispersing agent, cross-linked agent and starch on the performances of adhesive were investigated.

  4. A Milk Protein, Casein, as a Proliferation Promoting Factor in Prostate Cancer Cells

    Science.gov (United States)

    Park, Sung-Woo; Kim, Joo-Young; Kim, You-Sun; Lee, Sang Jin; Chung, Moon Kee

    2014-01-01

    Purpose Despite most epidemiologic studies reporting that an increase in milk intake affects the growth of prostate cancer, the results of experimental studies are not consistent. In this study, we investigated the proliferation of prostate cancer cells treated with casein, the main protein in milk. Materials and Methods Prostate cancer cells (LNCaP and PC3), lung cancer cells (A459), stomach cancer cells (SNU484), breast cancer cells (MCF7), immortalized human embryonic kidney cells (HEK293), and immortalized normal prostate cells (RWPE1) were treated with either 0.1 or 1 mg/mL of α-casein and total casein extracted from bovine milk. Treatments were carried out in serum-free media for 72 hours. The proliferation of each cell line was evaluated by an 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Results α-Casein and total casein did not affect the proliferations of RWPE1, HEK293, A459, SNU484, MCF7, HEK293, or RWPE1 cells. However, PC3 cells treated with 1 mg/mL of α-casein and casein showed increased proliferation (228% and 166%, respectively), and the proliferation of LNCaP cells was also enhanced by 134% and 142%, respectively. The proliferation mechanism of α-casein in PC3 and LNCaP cells did not appear to be related to the induction of Insulin-like growth factor-1 (IGF-1), since the level of IGF-1 did not change upon the supplementation of casein. Conclusions The milk protein, casein, promotes the proliferation of prostate cancer cells such as PC3 and LNCaP. PMID:25237656

  5. Quantification of bio- and techno-functional peptides in tryptic bovine micellar casein and β-casein hydrolysates.

    Science.gov (United States)

    Holder, Aline; Thienel, Katharina; Klaiber, Iris; Pfannstiel, Jens; Weiss, Jochen; Hinrichs, Jörg

    2014-09-01

    Numerous peptides generated by triptic hydrolysis of micellar casein and β-casein from bovine milk have been reported to exhibit bio-functional or techno-functional activities. In this study, the focus was placed on the quantification of eleven potential functional peptides generated by enzymatic hydrolysis with trypsin. The identity of the target peptides was verified by LC-ESI-MS/MS and a reverse phase high performance liquid chromatography method (RP-HPLC) was established to quantify the peptides. The quantification was based on calibration curves drawn using synthesised purified peptides. The regression analysis comparing >30 standard measurements of each peptide standard showed a regression coefficient R(2)>0.9958. The inter-day repeatability of the quantification method was always within a relative error of 0.2-6.5%, while the relative error of the accuracy for reproducibility was in the range of 0.1-2.4%. The established method was successfully applied for the quantitative analysis of the eleven functional peptides in different dairy fractions generated by cross-flow ultrafiltration.

  6. Solution and film properties of sodium caseinate/glycerol and sodium caseinate/polyethylene glycol edible coating systems.

    Science.gov (United States)

    Siew, D C; Heilmann, C; Easteal, A J; Cooney, R P

    1999-08-01

    The aim of this study is to determine the effects of plasticizer hydrogen bonding capability and chain length on the molecular structure of sodium caseinate (NaCAS), in NaCAS/glycerol and NaCAS/polyethylene glycol 400 (PEG) systems. Both solution and film phases were investigated. Glycerol and PEG reduced the viscosity of aqueous NaCAS, with the latter having a greater effect. This was explained in terms of protein/plasticizer aggregate size and changes to the conformation of the caseinate chain. In the film phase, glycerol caused more pronounced changes to the film tensile strength compared with PEG. However, the effect of glycerol on film water vapor permeability was smaller. These observations are attributed to the differences in plasticizer size and hydrogen bonding strength that controls the protein-plasticizer and protein-protein interactions in the films. Glass transition calculations from the tensile strength data indicate that the distribution of bonding interactions is more homogeneous in NaCAS/PEG films than in NaCAS/glycerol films.

  7. A novel method for separation of caseins from milk by phosphates precipitation.

    Science.gov (United States)

    Yen, Chon-Ho; Lin, Yin-Shen; Tu, Ching-Fu

    2015-01-01

    Milk protein of farm animals is difficult to isolate because of the presence of casein micelles, which are hard to separate from whey by using centrifugation or filtration. Insoluble casein micelles also create an obstacle for purification instruments to operate efficiently. The conventional method, to precipitate caseins by lowering pH to 4.6 and then recover the whey fraction for further purification using chromatography techniques, is not applicable to proteins having an isoelectric point similar to caseins. In addition, the acid condition used for casein removal usually leads to significantly poor yields and reduced biological activities. In this study, a novel method of precipitating caseins under neutral or weak acidic conditions is presented. The method employs a phosphate salt and a freeze-thaw procedure to obtain a casein-free whey protein fraction. This fraction contains more than 90% yield with little loss of bioactivity of the target protein, and is readily available for further chromatographic purification. This method was successfully applied to purify recombinant human factor IX and recombinant hirudin from the milk of transgenic pigs in the presented study. It is an efficient pretreatment approach prior to chromatographic purification of milk protein from farm animals and particularly of great value to collect those recombinants secreted from transgenic livestock.

  8. Spectrofluoremetric and molecular docking study on the interaction of bisdemethoxycurcumin with bovine β-casein nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Mehranfar, Fahimeh [Department of Chemistry, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Bordbar, Abdol-Khalegh, E-mail: bordbar@chem.ui.ac.ir [Department of Chemistry, University of Isfahan, Isfahan 81746-73441 (Iran, Islamic Republic of); Keyhanfar, Mehrnaz; Behbahani, Mandana [Faculty of Advanced Sciences and Technologies, Department of Biotechnology, University of Isfahan, Isfahan, 81746-73441 (Iran, Islamic Republic of)

    2013-11-15

    The interaction of bisdemethoxycurcumin (BDMC), as one of the main active component of turmeric (Curcuma longa L.), with bovine β-casein nanoparticle, as an efficient drug carrier system, was investigated using steady-state fluorescence spectroscopy and molecular docking calculations. Results of fluorescence quenching experiments, Forster energy transfer measurements and molecular docking calculations suggested that BDMC bind to the hydrophobic core of β-casein via formation of 3 hydrogen bonds and several vander Waals contacts that represented the encapsulation of BDMC in β-casein micelle nanoparticles. The binding parameters including number of substantive binding sites and the binding constants were evaluated by fluorescence quenching method. Additionally, the cytotoxicity of free BDMC and BDMC-β-casein complex in human breast cancer cell line MCF7 was evaluated in vitro. The study revealed the higher cytotoxic effects of encapsulated BDMC on MCF7 cells compared to equal dose of free BDMC. -- Highlights: • BDMC binds to the hydrophobic core of β-casein. • The effective encapsulation of BDMC in β-casein micelle nanoparticles was shown. • Enhanced cytotoxicity was observed for encapsulated BDMC in β-casein nanoparticles.

  9. Proteomic characterization of specific minor proteins in the human milk casein fraction.

    Science.gov (United States)

    Liao, Yalin; Alvarado, Rudy; Phinney, Brett; Lönnerdal, Bo

    2011-12-02

    Human milk contains many bioactive proteins that are likely to support the early development of the newborn. The aim of this study was to identify whether there are specific minor proteins associated with the human milk casein micelle prepared by the acid precipitation method. Protein identification was performed by liquid chromatography tandem mass spectrometry analysis. Eighty-two proteins were identified in the casein micelle, 18 of which are not present in their whey compartment. Thirty-two of these proteins specifically associated with the casein micelle have not previously been identified in human milk or colostrum. Proteins involved in immune function comprised the major part (28%) of total proteins, and another significant part is involved in metabolism/energy production (22%). Most of the proteins were of extracellular or cytoplasmic origin (accounting for 50 and 29%, respectively). This study indicates that various soluble proteins should be considered as part of the casein compartment, prepared by the acid precipitation method. The data provide new insight not only into the proteomic profile of the human milk casein micelle and its physiological significance, but also into the proper proportion of casein and casein-associated proteins to use in infant formula.

  10. Association of triclosan to casein proteins through solvent-mediated high-pressure homogenization.

    Science.gov (United States)

    Roach, A; Dunlap, J; Harte, F

    2009-03-01

    The association of triclosan (TCS), a widely used hydrophobic compound, to the bovine casein micelle is investigated in this study. The use of high-pressure homogenization (HPH) at 0, 100, 200, and 300 MPa was introduced as a method for the dissociation of casein micelles in a skim milk/ethanol solution (1: 1, v/v) in the presence of TCS at 20, 80, and 160 mg/L where ethanol evaporation served as the final step for TCS association to caseins. The majority of TCS (over 80%) was associated with the caseins regardless of initial TCS concentration or applied pressure. TCS association to caseins was enhanced by 30% with continued pressurization to 300 MPa. Micellar dissociation and reassociation was found to be an irreversible process as evidenced by microscopy images. Pressurization to 300 MPa resulted in the formation of an integrated protein network of casein proteins and noncovalently linked whey proteins where the solubility of TCS was enhanced up to 40 times its reported water solubility at the highest initial TCS level of 160 mg/L. Reformed micelles exhibited Newtonian flow behavior at all pressure levels. This study provides evidence for the solubility enhancing quality of TCS through the solvent-mediated pressure/shear-induced dissociation of casein proteins.

  11. Nutritional evaluation of caseins and whey proteins and their hydrolysates from Protamex

    Institute of Scientific and Technical Information of China (English)

    SINDAYIKENGERA Séverin; XIA Wen-shui

    2006-01-01

    Whey protein concentrate (WPC 80) and sodium caseinate were hydrolyzed by Protamex to 5%, 10%, 15%, and 20% degree of hydrolysis (DH). WPC 80, sodium caseinate and their hydrolysates were then analyzed, compared and evaluated for their nutritional qualities. Their chemical composition, protein solubility, amino acid composition, essential amino acid index (EAA index), biological value (BV), nutritional index (NI), chemical score, enzymic protein efficiency ratio (E-PER) and in vitro protein digestibility (IVPD) were determined. The results indicated that the enzymatic hydrolysis of WPC 80 and sodium caseinate by Protamex improved the solubility and IVPD of their hydrolysates. WPC 80, sodium caseinate and their hydrolysates were high-quality proteins and had a surplus of essential amino acids compared with the FAO/WHO/UNU (1985) reference standard.The nutritive value of WPC 80 and its hydrolysates was superior to that of sodium caseinate and its hydrolysates as indicated by some nutritional parameters such as the amino acid composition, chemical score, EAA index and predicted BV. However, the E-PER was lower for the WPC hydrolysates as compared to unhydrolyzed WPC 80 but sodium caseinate and its hydrolysates did not differ significantly. The nutritional qualities of WPC 80, sodium caseinate and their hydrolysates were good and make them appropriate for food formulations or as nutritional supplements.

  12. Nutritional evaluation of caseins and whey proteins and their hydrolysates from Protamex.

    Science.gov (United States)

    Sindayikengera, Séverin; Xia, Wen-shui

    2006-02-01

    Whey protein concentrate (WPC 80) and sodium caseinate were hydrolyzed by Protamex to 5%, 10%, 15%, and 20% degree of hydrolysis (DH). WPC 80, sodium caseinate and their hydrolysates were then analyzed, compared and evaluated for their nutritional qualities. Their chemical composition, protein solubility, amino acid composition, essential amino acid index (EAA index), biological value (BV), nutritional index (NI), chemical score, enzymic protein efficiency ratio (E-PER) and in vitro protein digestibility (IVPD) were determined. The results indicated that the enzymatic hydrolysis of WPC 80 and sodium caseinate by Protamex improved the solubility and IVPD of their hydrolysates. WPC 80, sodium caseinate and their hydrolysates were high-quality proteins and had a surplus of essential amino acids compared with the FAO/WHO/UNU (1985) reference standard. The nutritive value of WPC 80 and its hydrolysates was superior to that of sodium caseinate and its hydrolysates as indicated by some nutritional parameters such as the amino acid composition, chemical score, EAA index and predicted BV. However, the E-PER was lower for the WPC hydrolysates as compared to unhydrolyzed WPC 80 but sodium caseinate and its hydrolysates did not differ significantly. The nutritional qualities of WPC 80, sodium caseinate and their hydrolysates were good and make them appropriate for food formulations or as nutritional supplements.

  13. Characterization and genetic analysis of bovine alpha S1-casein I variant.

    Science.gov (United States)

    Lühken, G; Caroli, A; Ibeagha-Awemu, E M; Erhardt, G

    2009-08-01

    The aim of this study was to identify the molecular genetic origin underlying the I variant of alpha(s1)-casein and to develop a DNA-based test for this polymorphism as a tool for genetic analyses independent of milk sample testing. All coding exons and flanking regions of the alpha(s1)-casein gene were sequenced in DNA samples from cattle of known alpha(s1)-casein genotypes (BI, CI, II, CC), determined by isoelectric focusing of milk samples. A nucleotide substitution (A>T) in exon 11 (g.19836A>T) leads to the exchange of Glu with Asp at amino acid position 84 of the mature protein (p.Glu84Asp) and perfectly co-segregated with the presence of the alpha(s1)-casein I variant in the milk of the analysed animals. Genotyping of a total of 680 DNA samples from 31 Bos taurus and Bos indicus cattle breeds and from Bos grunniens, Bison bison and Bison bonasus by restriction fragment length polymorphism analysis revealed the occurrence of Asp at position 84 at low frequencies in Bos taurus and Bos indicus breeds and established its origin from the alpha(s1)-casein C variant (p.Glu192Gly). Ten different intragenic haplotypes in the gene region from intron 8 to intron 12 were observed by sequencing, of which two occurred in Bison bison and one in Bison bonasus only. Using available casein gene complex information, an association of Asp at position 84 to beta-casein A(2) and kappa-casein B was shown in the Bos indicus breed Banyo Gudali. Taken together, we can postulate that the alpha(s1)-casein variant I is caused by a non-synonymous nucleotide substitution in exon 11 of the gene and that it originated within Bos indicus and spread to Bos taurus subsequently.

  14. β-casein as a functional food component

    DEFF Research Database (Denmark)

    Sulewska, Anna Maria

    Milk is a complex mixture of various components which include proteins, carbohydrates, lipids and minerals. Milk proteins can be divided into two classes: whey proteins (20%) and caseins (80% of total milk protein). As thermal treatment is a traditional method of food preservation, interactions...... which can improve stability and safety of food. Traditional methods of food preservation and sterilization require high temperature, which may result in undesirable changes such as change of color or texture. Development of novel food processing methods, which allow to create new milk-based products...... with novel textures, is highly valuable to the dairy industry. Understanding interactions that undergo during food processing is necessary for proper design of process. For example control of aggregation is required to achieve desired texture of the final product....

  15. Detecting β-Casein Variation in Bovine Milk

    Directory of Open Access Journals (Sweden)

    Anna Maria Caroli

    2016-01-01

    Full Text Available In bovine species, β-casein (β-CN is characterized by genetic polymorphism. The two most common protein variants are β-CN A2 (the original one and A1, differing from A2 for one amino acid substitution (Pro67 to His67. Several bioactive peptides affecting milk nutritional properties can originate from β-CN. Among them, β-casomorphin-7 (BCM7 ranging from amino acid 60 to 66 can be released more easily from β-CN variants carrying His67 (A1 type instead of Pro67 (A2 type. Nowadays, “A2 milk” is produced in different countries claiming its potential benefits in human health. The aim of this study was to further develop and apply an isoelectric focusing electrophoresis (IEF method to bulk and individual milk samples in order to improve its use for β-CN studies. We succeeded in identifying A2 milk samples correctly and quantifying the percentage of A2, A1, and B variants in bulk samples not derived from A2 milk as well as in individual milk samples. The method allows us to quantify the relative proportion of β-CN variants in whole milk without eliminating whey protein by acid or enzymatic precipitation of caseins. The aim of this study was also to study the different behavior of β-CN and β-lactoglobulin (β-LG in the presence of trichloroacetic acid (TCA. The higher sensitivity of β-CN to TCA allows quantifying β-CN variants after TCA fixation because β-LG is not visible. Monitoring β-CN variation in cattle breeds is important in order to maintain a certain balance between Pro67 and His67 in dairy products. Overall, the debate between A1 and A2 milk needs further investigation.

  16. Restriction fragment length polymorphism of ovine casein genes: close linkage between the alpha s1-, alpha s2-, beta- and kappa-casein loci.

    Science.gov (United States)

    Leveziel, H; Metenier, L; Guerin, G; Cullen, P; Provot, C; Bertaud, M; Mercier, J C

    1991-01-01

    Restriction fragment length polymorphism (RFLP) of ovine casein genes was investigated. Genomic DNA from 56 rams was digested with 10 restriction endonucleases and Southern blots probed with the four ovine casein cDNAs (alpha s1-, beta-, alpha s2- and kappa-Cn). Five enzymes, namely, BglI, PvuII, RsaI, TaqI and HindIII revealed nine different RFLPs. The inheritance of six of these polymorphisms was studied by segregation analysis of gametes in nine rams' families, and each of them could be related to the existence of alleles at the relevant casein locus. A close linkage between the four ovine casein genes was demonstrated since no recombination within the four pairs of loci examined, alpha s1-beta-Cn, alpha s1-kappa-Cn, beta-kappa-Cn and alpha s2-kappa-Cn, was observed in the progeny of double heterozygous rams. The casein genes are thus clustered in the ovine species as in the case of other mammals.

  17. Comparative screening of single nucleotide polymorphisms in β-casein and κ-casein gene in different livestock breeds of India.

    Science.gov (United States)

    Singh, Lakshya Veer; Jayakumar, S; Sharma, Anurodh; Gupta, Shishir Kumar; Dixit, S P; Gupta, Neelam; Gupta, S C

    2015-06-01

    The most polymorphic milk protein gene is β-casein; 13 protein variants are known in cattle. Milk protein genetic polymorphism has received considerable research interest in recent years because of possible associations between milk protein and economically important traits in livestock. The present study was undertaken to explore the genetic polymorphisms in exon 7 of β-casein and exon 4 of κ-casein genes in Arunachali yaks (Bos grunniens), Sahiwal (Bos indicus) cattle, malpura sheep (Ovis aries) and Gaddi goat (Capra hircus). Results of the study revealed presence of 11 SNP variants in all livestock species. Four SNPs were observed in Bos indicus; two SNPs in Bos grunniens; three SNPs in Ovis aries and three SNPs in Capra hircus. These variations are found to be synonymous in nature as these variations do not result in their corresponding amino acids. A total of five polymorphic sites have been described at the κ-casein (CSN3) locus in the Indian domestic Gaddi goat (Capra hircus) when compared with exotic goat (X60763) while sequence analysis of κ-casein gene in sheep showed three novel nucleotide changes in malpura sheep when compared with the exotic sheep (AY237637). These results highlight the importance of taking into consideration the CSN3 SNPs when performing selection for milk composition in dairy livestock breeds.

  18. Hydrolyzed casein reduces diet-induced obesity in male C57BL/6J mice

    DEFF Research Database (Denmark)

    Lillefosse, Haldis Haukås; Tastesen, Hanne Sørup; Du, Zhen-Yu;

    2013-01-01

    The digestion rate of dietary protein is a regulating factor for postprandial metabolism both in humans and animal models. However, few data exist about the habitual consumption of proteins with different digestion rates with regard to the development of body mass and diet-induced obesity. Here, we...... used a factorial ANOVA design to investigate the effects of protein form (intact vs. hydrolyzed casein) and protein level (16 vs. 32 energy percent protein) on body mass gain and adiposity in obesity-prone male C57BL/6J mice fed Western diets with 35 energy percent fat. Mice fed the hydrolyzed casein...... by hydrolyzed casein ingestion translated into decreased body and adipose tissue masses. We conclude that chronic consumption of extensively hydrolyzed casein reduces body mass gain and diet-induced obesity in male C57BL/6J mice....

  19. Spectroscopic Evaluation of Effects of Heat Treatments on the Structures and Emulsifying Properties of Caseins

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hao; WANG Peng-jie; LEI Xin-gen; YANG Hong-ju; ZHANG Lu-da; REN Fa-zheng; ZHENG Li-min

    2013-01-01

    The effects of heat treatment(heating temperature and pH) on the structures and emulsifying properties of caseins were systematically studied by spectroscopy.Heat treatment from 60 to 100 ℃ resulted in an increase in their fluorescence intensity,hydrodynamic diameter,turbidity and emulsifying activity index,but decreased the size polydispersity of caseins.In the pH range of 5.5 to 7.0,the fluorescence intensity,hydrodynamic diameter,turbidity and emulsifying properties decreased with increased heating pH,but the size polydispersity of caseins increased with increased pH.The relationship between the surface fluorescence intensity and emulsifying activity was also investigated,revealing a correlation coefficient of 0.90.These results suggested that heat treatment could be used to modify the structures and emulsifying properties of caseins by appropriately selecting heating conditions.

  20. Skim Milk, Whey, and Casein Increase Body Weight and Whey and Casein Increase the Plasma C-Peptide Concentration in Overweight Adolescents12

    DEFF Research Database (Denmark)

    Arnberg, Karina; Mølgaard, Christian; Michaelsen, Kim Fleischer

    2012-01-01

    insulin, and insulin secretion estimated as the plasma C-peptide concentration in overweight adolescents. Overweight adolescents (n = 203) aged 12–15 y with a BMI of 25.4 ± 2.3 kg/m2 (mean ± SD) were randomized to 1 L/d of skim milk, whey, casein, or water for 12 wk. All milk drinks contained 35 g protein....... Outcomes were BMI-for-age Z-scores (BAZs), waist circumference, plasma insulin, homeostatic model assessment, and plasma C-peptide. We found no change in BAZ in the pretest control and water groups, whereas it was greater at 12 wk in the skim milk, whey, and casein groups compared with baseline...... and with the water and pretest control groups. The plasma C-peptide concentration increased from baseline to wk 12 in the whey and casein groups and increments were greater than in the pretest control (P milk or water group. These data suggest...

  1. Electrochemical Sensing of Casein Based on the Interaction between Its Phosphate Groups and a Ruthenium(III) Complex.

    Science.gov (United States)

    Inaba, Iku; Kuramitz, Hideki; Sugawara, Kazuharu

    2016-01-01

    A reaction to casein, along with β-lactoglobulin, is a main cause of milk allergies, and also is a useful indicator of protein in allergic analyses. In the present study, a simple casein sensor was developed based on the interaction between a phosphate group of casein and electroactive [Ru(NH3)6](3+). We evaluated the voltammetric behavior of a casein-[Ru(NH3)6](3+) complex using a glassy carbon electrode. When the ruthenium(III) complex was combined with the phosphate groups of casein, the structure of the casein was changed. Since the hydrophobicity of casein was increased due to the binding, the casein was adsorbed onto the electrode. Furthermore, we modified an electrode with a ruthenium(III) ions/collagen film. When the sensor was applied to the detection of the casein contained in milk, the values coincided with those indicated by the manufacturer. Accordingly, this electrode could be a powerful sensor for the determination of casein in several foods.

  2. Effect of boiling on the antidiabetic property of enzyme treated sheep milk casein

    OpenAIRE

    Farhath Jan; Santosh Kumar; Richa Jha

    2016-01-01

    Aim: Sheep milk-born bioactive peptides have been found to exhibit various physiological activities. The present work was designed with the aim to evaluate the effect of boiling on antidiabetic property of peptides derived from sheep milk caseinate on hydrolysis with three different proteases. Materials and Methods: In this investigation, casein prepared from raw and boiled sheep milk was hydrolyzed by three commercially available proteases (trypsin, pepsin, and chymotrypsin). These hydrol...

  3. Systematic Characterization of the Immune Response to Gluten and Casein in Autism Spectrum Disorders. Revision

    Science.gov (United States)

    2013-08-01

    of the Immune Response to Gluten and Casein in Autism Spectrum Disorders PRINCIPAL INVESTIGATOR: Armin Alaedini, PhD CONTRACTING... Gluten and Casein in Autism Spectrum Disorders 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH 10-1-0887 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...heterogeneity within this spectrum and the lack of biomarkers to characterize disease phenotypes and to understand treatment outcome. Dietary gluten

  4. Adsorption of hydrophobin/β-casein mixtures at the solid-liquid interface.

    Science.gov (United States)

    Tucker, I M; Petkov, J T; Penfold, J; Thomas, R K; Cox, A R; Hedges, N

    2016-09-15

    The adsorption behaviour of mixtures of the proteins β-casein and hydrophobin at the hydrophilic solid-liquid surface have been studied by neutron reflectivity. The results of measurements from sequential adsorption and co-adsorption from solution are contrasted. The adsorption properties of protein mixtures are important for a wide range of applications. Because of competing factors the adsorption behaviour of protein mixtures at interfaces is often difficult to predict. This is particularly true for mixtures containing hydrophobin as hydrophobin possesses some unusual surface properties. At β-casein concentrations ⩾0.1wt% β-casein largely displaces a pre-adsorbed layer of hydrophobin at the interface, similar to that observed in hydrophobin-surfactant mixtures. In the composition and concentration range studied here for the co-adsorption of β-casein-hydrophobin mixtures the adsorption is dominated by the β-casein adsorption. The results provide an important insight into how the competitive adsorption in protein mixtures of hydrophobin and β-casein can impact upon the modification of solid surface properties and the potential for a wide range of colloid stabilisation applications.

  5. Micellisation and immunoreactivities of dimeric beta-caseins.

    Science.gov (United States)

    Yousefi, Reza; Gaudin, Jean-Charles; Chobert, Jean-Marc; Pourpak, Zahra; Moin, Mostafa; Moosavi-Movahedi, Ali Akbar; Haertle, Thomas

    2009-12-01

    Bovine beta-casein (beta-CN) is a highly amphiphilic micellising phospho-protein showing chaperone-like activity in vitro. Recently, existence of multiple sequential epitopes on beta-CN polypeptide chain in both hydrophilic-polar (psi) and hydrophobic-apolar domains (phi) has been evidenced. In order to clarify specific contribution of polar and apolar domains in micellisation process and in shaping immunoreactivity of beta-CN, its dimeric/bi-amphiphilic "quasi palindromic" forms covalently connected by a disulfide bond linking either N-terminal (C4 beta-CND) or C-terminal domain (C208 beta-CND) were produced and studied. Depending on the C- or N-terminal position of inserted cysteine, each dimeric beta-CN contains one polar/apolar region at the centre and two external hydrophobic/hydrophilic ends. Consequently, such casein dimers have radically different polarities/hydrophobicities on their outside surfaces. Dynamic light scattering (DLS) measurements indicate that these dimeric casein molecules form micelles of different sizes depending on arrangement of polar fragments of the beta-CN mutants in their constrained dimers. Non-aggregated dimers have different hydrodynamic diameters that could be explained by their different geometries. Measurements of fluorescence showed more hydrophobic environment of Trp residues of C208 beta-CND, while in similar experimental conditions Trp residues of C4 beta-CND and native beta-CN were more exposed to the polar medium. Both fluorescence and DLS studies showed greater propensity for micellisation of the dimeric beta-CNs, suggesting that the factors inducing the formation of micelles are stronger in the bi-amphiphilic dimers. 1-anilino-naphthalene-8-sulfonate (ANS) binding studies showed different binding of ANS by these dimers as well as different exposition of ANS binding (hydrophobic) regions in the micellar states. The differences in fluorescence resonance energy transfer (FRET) profiles of C4 beta-CND and C208 beta-CND can

  6. Mayaro virus infection cycle relies on casein kinase 2 activity.

    Science.gov (United States)

    Barroso, Madalena M S; Lima, Carla S; Silva-Neto, Mário A C; Da Poian, Andrea T

    2002-09-06

    Replication of Mayaro virus in Vero cells induces dramatic cytopathic effects and cell death. In this study, we have evaluated the role of casein kinase 2 (CK2) during Mayaro virus infection cycle. We found that CK2 was activated during the initial stages of infection ( approximately 36% after 4h). This activation was further confirmed when the enzyme was partially purified from the cellular lysate either by Mono Q 5/5Hr column or heparin-agarose column. Using this later column, we found that the elution profile of CK2 activity from infected cells was different from that obtained for control cell enzyme, suggesting a structural modification of CK2 after infection. Treatment of infected cells with a cell-permeable inhibitor of CK2, dichloro-1-(beta-D-ribofuranosyl)benzimidazole (DRB), abolished the cytopathic effect in a dose-dependent manner. Together this set of data demonstrates for the first time that CK2 activity in host cells is required in Mayaro virus infection cycle.

  7. [Effects of glycerol on the spectral properties of sodium caseinate].

    Science.gov (United States)

    Li, Yan; Chang, Fen-fen; Gao, Huan-yuan; Cao, Qing; Jin, Li-e

    2015-01-01

    Although the immigration of water molecule, and diffusion and traversing of oxygen can be prevented by the edible film prepared through sodium caseinate, which plays a good protection role for the food, the strong hydrophilicity makes its watertightness and mechanical properties become inferior. Because the toughness and water resistance of SC films can be enhanced by glycerol (G) as an additive, it is necessary to elucidate the interaction between G and SC through the spectral characteristics such as fluorescence spectra, infrared spectra and UV spectra. The results show that the fluorescence intensity of SC decreases due to the addition of G. The binding constant obtained by the double logarithmic regression curve analysis is 1. 127 x 10(3) L . mol-1 and the number of binding sites reaches 1. 161. It indicates that the weak chemical bond is primary between G and SC molecules; From IR the absorption peaks of SC are almost the same before and after adding G. However, there is a certain difference among their absorption intensities. It reveals that the secondary structure of SC is affected, β folding length decreases, α helix, random coil structure, β angle structure increases, and the intermolecular hydrogen bond is strengthened; From UV the peptide bond structure of SC is not changed after the addition of G, but the polymer with larger molecular weight, which is formed by non-covalent bond, makes the peak intensity decrease. The research gives the mode of G and SC from the molecular level.

  8. Casein/pectin nanocomplexes as potential oral delivery vehicles.

    Science.gov (United States)

    Luo, Yangchao; Pan, Kang; Zhong, Qixin

    2015-01-01

    Delivery systems prepared with natural biopolymers are of particular interests for applications in food, pharmaceutics and biomedicine. In this study, nanocomplex particles of sodium caseinate (NaCas) and pectin were fabricated and investigated as potential oral delivery vehicles. Nanocomplexes were prepared with three mass ratios of NaCas/pectin by acidification using glucono-δ-lactone and thermal treatment. NaCas/pectin at 1:1 mass ratio resulted in dispersions with the lowest turbidity and the smallest and most uniform nanocomplexes. Thermal treatment at 85 °C for 30 min facilitated the formation of stable, compact, and spherical nanocomplexes. Heating not only greatly increased the yield of nanocomplexes but also significantly improved the encapsulation capability of rutin studied as a model compound. Pectin in nanocomplexes delayed the hydrolysis of NaCas by pepsin at gastric conditions and enabled the controlled release of most rutin in simulated intestinal conditions. The nanocomplexes based on food-sourced biopolymers have promising features for oral delivery of nutrients and medicines.

  9. Ser2 is the autophosphorylation site in the beta subunit from bicistronically expressed human casein kinase-2 and from native rat liver casein kinase-2 beta

    DEFF Research Database (Denmark)

    Boldyreff, B; James, P; Staudenmann, W;

    1993-01-01

    Human casein kinase-2 (CK-2) subunits alpha and beta were bicistronically expressed in bacteria. The recombinant holoenzyme shared all investigated properties with the native CK-2 from mammalian sources (rat liver, Krebs II mouse ascites tumour cells). Contrary to recombinant human CK-2 produced...

  10. Investigating cold gelation properties of recombined highly concentrated micellar casein concentrate and cream for use in cheese making.

    Science.gov (United States)

    Lu, Y; McMahon, D J; Vollmer, A H

    2016-07-01

    Highly concentrated micellar casein concentrate (HC-MCC), a potential ingredient for cheese making, contains ~20% casein with ~70% of serum proteins removed by microfiltration and diafiltration of skim milk, followed by vacuum evaporation. Our objective was to investigate cold gelation properties of recombined concentrated milk (RCM) by mixing thawed frozen HC-MCC and cream under different casein levels, pH, and protein-to-fat ratios, and with addition of sodium citrate or calcium. The HC-MCC was recombined with cream using low shear at 50°C for 30 min, and rheological measurements were conducted. Cold-gelling temperature [the temperature at which storage modulus (G')=loss modulus (G″)] was linearly correlated with casein levels from 8.6 to 11.5% (R(2)=0.71), pH from 6.6 to 7.0 (R(2)=0.96), and addition of sodium citrate from 0 to 0.36mmol/g of casein (R(2)=0.80). At pH 7.0, gelation occurred at 12, 26, and 38°C with 9, 10, and 11% casein, respectively. At pH 6.6, 6.8, and 7.0, RCM with 12% casein gelled at a mean temperature of 12, 26, and 37°C, respectively. Adding calcium chloride at 0.17mmol/g of casein significantly increased cold-gelling temperature from 18 to ≥50°C, whereas no significant change was observed at levels up to 0.12mmol/g of casein. Different protein to fat ratios ranging from 0.8 to 1.2 did not significantly influence gelling temperature. In transmission electron micrographs of RCM with 12% casein, casein micelles were nonspherical and partially dissociated into small protein strands. Upon addition of calcium chloride at 0.21mmol/g of casein, casein micelles were more spherical and retained colloidal structure with the presence of aggregated casein micelles. These gelation processes of RCM with or without addition of trisodium citrate were both reversible. We propose that cold gelation of RCM occurs when protein strands that have been partially released from the casein micelles entangle, restrict their mobility, and form a fine

  11. Moleculer analysis of genotype kappa casein and composition of goat milk Etawah grade, Saanen and their crossbred

    OpenAIRE

    Yayu Zurriyati; R. R. Noor; R. R. A. Maheswari

    2011-01-01

    Polymorphism of goat casein gene closely linked to the quality of milk protein. κ-casein is one of the casein fractions that influence the shape and stability of grain milk. This study is aimed to identify the variation of genotype κ-casein and related with milk quality from Etawah grade, Saanen and their crossbreed (PE-SA). The number of dairy goats used in this study was 150 animals consisted of Etawah grade (48 animals), Saanen (51 animals) and PE-SA (51 animals). Steps of experiment were:...

  12. Effect of cross-linking on microstructure and physical performance of casein protein.

    Science.gov (United States)

    Ghosh, Arun; Ali, M Azam; Dias, George J

    2009-07-13

    The development of advanced materials from biorenewable protein biopolymers requires the generation of more exogenous bonds to maintain the microstructure and durability in the final products. Casein is the main protein of milk, representing about 80% of the total protein. In the present investigation the casein protein was solubilized and/or emulsified in aqueous alkaline solutions, and 2D films and 3D matrices were produced. The effects of silane (3-aminopropyl triethoxy silane), DL-glyceraldehyde and glutaraldehyde on tensile properties and water swelling/absorption of 2D casein films and also the microstructure of the freeze-dried 3D matrices were analyzed. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that there were no significant changes in the molecular weight (19-23.9 kDa) of the casein proteins on exposure to alkaline solutions of sodium hydroxide and silane. The casein films produced without glycerol plasticizer and with heat treatment (130 °C for 18 h) were fragile. However, the fragile films were transformed into ductile and tough materials on exposure to moisture (i.e., conditioned for one week at 50 ± 2% relative humidity and 22 ± 2 °C) and showed a maximum average tensile strength of 49-52 MPa and modulus of 1107-1391 MPa. The chemical cross-linkers (i.e., DL-glyceraldehyde and glutaraldehyde) improved the microstructure of glycerol plasticized casein protein, when analyzed under scanning electron microscope (SEM). Furthermore, these chemical cross-linking agents enhanced the mechanical properties and water resistant properties of casein films.

  13. Characterization of the casein gene complex in West African goats and description of a new alpha(s1)-casein polymorphism.

    Science.gov (United States)

    Caroli, A; Chiatti, F; Chessa, S; Rignanese, D; Ibeagha-Awemu, E M; Erhardt, G

    2007-06-01

    The analysis of casein polymorphisms was carried out in West Africa goat populations: Red Sokoto (n = 57), West African Dwarf Nigeria (n = 27), West African Dwarf Cameroon (n = 39), and Borno (n = 37). The 4 casein genes alpha(s1) (CSN1S1), beta (CSN2), alpha(s2) (CSN1S2), and kappa (CSN3) were typed at the DNA level. No null alleles were found in any of the genes analyzed. A PCR single-strand conformation polymorphism method was implemented for the identification of CSN1S1*F allele simultaneously with A/0(1), B/E, N and the new allele. The allele differed from CSN1S1*B by a synonymous transversion TCG-->TCT in the codon corresponding to Ser(66) of the mature protein. The new allele, named CSN1S1*B', occurred at a high frequency in all the populations, ranging from 0.295 (West African Dwarf Cameroon) to 0.405 (Borno). A greater frequency was found for alleles associated with high alpha(s1)-casein quantity, as has already been observed in the goat populations from the Mediterranean area. The intermediate E allele occurred only in the Red Sokoto and at a low frequency. The faint F allele occurred in 3 populations at frequencies lower than 0.03. Linkage disequilibrium occurred in all the populations, with highly significant differences in Borno, Red Sokoto, and West Africa Dwarf Nigeria, and significant differences in West Africa Dwarf Cameroon. Only 10 haplotypes showed frequencies > or =0.05 in at least 1 of the 4 populations considered, and the overall frequency was >0.1 only for 4 haplotypes: BAAB, B'ACA, ACAB, and BACA (in the order CSN1S1-CSN2-CSN1S2-CSN3). Haplotype BAAB, postulated as an ancestral haplotype in previous studies, was the most common haplotype in all breeds except Borno, where B'ACA was predominant. The results obtained are of considerable significance given that very little information exists on the subject for African goats. The high frequency of strong alleles in the calcium-sensitive caseins as well as the high linkage disequilibrium found

  14. Skim milk, whey, and casein increase body weight and whey and casein increase the plasma C-peptide concentration in overweight adolescents.

    Science.gov (United States)

    Arnberg, Karina; Mølgaard, Christian; Michaelsen, Kim Fleischer; Jensen, Signe Marie; Trolle, Ellen; Larnkjær, Anni

    2012-12-01

    In adults, dietary protein seems to induce weight loss and dairy proteins may be insulinotropic. However, the effect of milk proteins in adolescents is unclear. The objective was to test whether milk and milk proteins reduce body weight, waist circumference, homeostatic model assessment, plasma insulin, and insulin secretion estimated as the plasma C-peptide concentration in overweight adolescents. Overweight adolescents (n = 203) aged 12-15 y with a BMI of 25.4 ± 2.3 kg/m(2) (mean ± SD) were randomized to 1 L/d of skim milk, whey, casein, or water for 12 wk. All milk drinks contained 35 g protein/L. Before randomization, a subgroup of adolescents (n = 32) was studied for 12 wk before the intervention began as a pretest control group. The effects of the milk-based test drinks were compared with baseline (wk 0), the water group, and the pretest control group. Diet and physical activity were registered. Outcomes were BMI-for-age Z-scores (BAZs), waist circumference, plasma insulin, homeostatic model assessment, and plasma C-peptide. We found no change in BAZ in the pretest control and water groups, whereas it was greater at 12 wk in the skim milk, whey, and casein groups compared with baseline and with the water and pretest control groups. The plasma C-peptide concentration increased from baseline to wk 12 in the whey and casein groups and increments were greater than in the pretest control (P milk or water group. These data suggest that high intakes of skim milk, whey, and casein increase BAZs in overweight adolescents and that whey and casein increase insulin secretion. Whether the effect on body weight is primary or secondary to the increased insulin secretion remains to be elucidated.

  15. Milk and growth in children: effects of whey and casein.

    Science.gov (United States)

    Mølgaard, Christian; Larnkjær, Anni; Arnberg, Karina; Michaelsen, Kim F

    2011-01-01

    Consumption of cow's milk is recommended in many countries. Observational and intervention studies show that cow's milk most likely has a positive influence on growth in children. The strongest evidence comes from observational studies and intervention studies in low-income countries, but there are also observational studies from high-income countries showing positive associations between milk intake and growth. Milk seems thus to have a specific stimulating effect on linear growth, not only in developing countries with high rates of malnutrition, but also in industrialized countries. However, it is not known which components in milk stimulate growth. Possible components are proteins, minerals, vitamins or combinations of these. Cow's milk proteins have a high protein quality, and whey has a slightly higher quality than casein, according to some indices based on amino acid composition. Studies, mainly from sport medicine, have suggested that whey protein also has the potential to increase muscle mass. Whether whey improves body composition to a larger extent than other milk proteins is not clear. The mechanism behind a possible growth-stimulating effect of milk and milk components is likely to be through a stimulation of insulin-like growth factor-I synthesis and maybe insulin secretion. In conclusion, there is strong evidence that milk stimulates linear growth. The mechanism is not yet clear, and more intervention studies are needed to understand which components in milk are responsible for the growth stimulation. The effects of milk on linear growth and adult height may have both positive and negative long-term implications.

  16. Casein kinase Iepsilon modulates the signaling specificities of dishevelled.

    Science.gov (United States)

    Cong, Feng; Schweizer, Liang; Varmus, Harold

    2004-03-01

    Wnt signaling is critical to many aspects of development, and aberrant activation of the Wnt signaling pathway can cause cancer. Dishevelled (Dvl) protein plays a central role in this pathway by transducing the signal from the Wnt receptor complex to the beta-catenin destruction complex. Dvl also plays a pivotal role in the planar cell polarity pathway that involves the c-Jun N-terminal kinase (JNK). How functions of Dvl are regulated in these two distinct pathways is not clear. We show that deleting the C-terminal two-thirds of Dvl, which includes the PDZ and DEP domains and is essential for Dvl-induced JNK activation, rendered the molecule a much more potent activator of the beta-catenin pathway. We also found that casein kinase Iepsilon (CKIepsilon), a previously identified positive regulator of Wnt signaling, stimulated Dvl activity in the Wnt pathway, but dramatically inhibited Dvl activity in the JNK pathway. Consistent with this, overexpression of CKIepsilon in Drosophila melanogaster stimulated Wnt signaling and disrupted planar cell polarity. We also observed a correlation between the localization and the signaling activity of Dvl in the beta-catenin pathway and the JNK pathway. Furthermore, by using RNA interference, we demonstrate that the Drosophila CKIepsilon homologue Double time positively regulates the beta-catenin pathway through Dvl and negatively regulates the Dvl-induced JNK pathway. We suggest that CKIepsilon functions as a molecular switch to direct Dvl from the JNK pathway to the beta-catenin pathway, possibly by altering the conformation of the C terminus of Dvl.

  17. Analysis of Casein Biopolymers Adsorption to Lignocellulosic Biomass as a Potential Cellulase Stabilizer

    Science.gov (United States)

    Eckard, Anahita Dehkhoda; Muthukumarappan, Kasiviswanathan; Gibbons, William

    2012-01-01

    Although lignocellulosic materials have a good potential to substitute current feedstocks used for ethanol production, conversion of these materials to fermentable sugars is still not economical through enzymatic hydrolysis. High cost of cellulase has prompted research to explore techniques that can prevent from enzyme deactivation. Colloidal proteins of casein can form monolayers on hydrophobic surfaces that alleviate the de-activation of protein of interest. Scanning electron microscope (SEM), fourier transform infrared spectroscopy (FT-IR), capillary electrophoresis (CE), and Kjeldahl and BSA protein assays were used to investigate the unknown mechanism of action of induced cellulase activity during hydrolysis of casein-treated biomass. Adsorption of casein to biomass was observed with all of the analytical techniques used and varied depending on the pretreatment techniques of biomass. FT-IR analysis of amides I and II suggested that the substructure of protein from casein or skim milk were deformed at the time of contact with biomass. With no additive, the majority of one of the cellulase mono-component, 97.1 ± 1.1, was adsorbed to CS within 24 h, this adsorption was irreversible and increased by 2% after 72 h. However, biomass treatment with skim-milk and casein reduced the adsorption to 32.9% ± 6.0 and 82.8% ± 6.0, respectively. PMID:23118515

  18. How to squeeze a sponge: casein micelles under osmotic stress, a SAXS study.

    Science.gov (United States)

    Bouchoux, Antoine; Gésan-Guiziou, Geneviève; Pérez, Javier; Cabane, Bernard

    2010-12-01

    By combining the osmotic stress technique with small-angle x-ray scattering measurements, we followed the structural response of the casein micelle to an overall increase in concentration. When the aqueous phase that separates the micelles is extracted, they behave as polydisperse repelling spheres and their internal structure is not affected. When they are compressed, the micelles lose water and shrink to a smaller volume. Our results indicate that this compression is nonaffine, i.e., some parts of the micelle collapse, whereas other parts resist deformation. We suggest that this behavior is consistent with a spongelike casein micelle having a triple hierarchical structure. The lowest level of the structure consists of the CaP nanoclusters that serve as anchors for the casein molecules. The intermediate level consists of 10- to 40-nm hard regions that resist compression and contain the nanoclusters. Those regions are connected and/or partially merged with each other, thus forming a continuous and porous material. The third level of structure is the casein micelle itself, with an average size of 100 nm. In our view, such a structure is consistent with the observation of 10- to 20-nm casein particles in the Golgi vesicles of lactating cells: upon aggregation, those particles would rearrange, fuse, and/or swell to form the spongelike micelle.

  19. Analysis of Casein Biopolymers Adsorption to Lignocellulosic Biomass as a Potential Cellulase Stabilizer

    Directory of Open Access Journals (Sweden)

    Anahita Dehkhoda Eckard

    2012-01-01

    Full Text Available Although lignocellulosic materials have a good potential to substitute current feedstocks used for ethanol production, conversion of these materials to fermentable sugars is still not economical through enzymatic hydrolysis. High cost of cellulase has prompted research to explore techniques that can prevent from enzyme deactivation. Colloidal proteins of casein can form monolayers on hydrophobic surfaces that alleviate the de-activation of protein of interest. Scanning electron microscope (SEM, fourier transform infrared spectroscopy (FT-IR, capillary electrophoresis (CE, and Kjeldahl and BSA protein assays were used to investigate the unknown mechanism of action of induced cellulase activity during hydrolysis of casein-treated biomass. Adsorption of casein to biomass was observed with all of the analytical techniques used and varied depending on the pretreatment techniques of biomass. FT-IR analysis of amides I and II suggested that the substructure of protein from casein or skim milk were deformed at the time of contact with biomass. With no additive, the majority of one of the cellulase mono-component, 97.1 ± 1.1, was adsorbed to CS within 24 h, this adsorption was irreversible and increased by 2% after 72 h. However, biomass treatment with skim-milk and casein reduced the adsorption to 32.9% ± 6.0 and 82.8% ± 6.0, respectively.

  20. The pressure-induced, lactose-dependent changes in the composition and size of casein micelles.

    Science.gov (United States)

    Wang, Pengjie; Jin, Shaoming; Guo, Huiyuan; Zhao, Liang; Ren, Fazheng

    2015-04-15

    The effects of lactose on the changes in the composition and size of casein micelles induced by high-pressure treatment and the related mechanism of action were investigated. Dispersions of ultracentrifuged casein micelle pellets with 0-10% (w/v) lactose were subjected to high pressure (400 MPa) at 20 °C for 40 min. The results indicated that the level of non-sedimentable caseins was positively related to the amount of lactose added prior to pressure treatment, and negatively correlated to the size. A mechanism for the pressure-induced, lactose-dependent changes in the casein micelles is proposed. Lactose inhibits the hydrophobic interactions between the micellar fragments during or after pressure release, through the hydrophilic layer formed by their hydrogen bonds around the micellar fragments. In addition, lactose does not favour the association between calcium and the casein aggregates after pressure release. Due to these two functions, lactose inhibited the formation of larger micelles after pressure treatment.

  1. Analysis of polymorphism in the bovine casein genes by use of the polymerase chain reaction.

    Science.gov (United States)

    Pinder, S J; Perry, B N; Skidmore, C J; Savva, D

    1991-01-01

    Methods have been devised for detecting polymorphisms in the bovine beta- and kappa-casein genes using the polymerase chain reaction (PCR) followed either by restriction enzyme digestion (to reveal a restriction fragment length polymorphism (RFLP] or by hybridization of an allele-specific oligonucleotide. These methods, as well as being faster and more sensitive than traditional RFLP methods, are of more general applicability since they can detect any change in DNA sequence. They require only a small sample of blood or semen and are applicable to animals of any age or sex. These methods make possible large-scale screening and thus selection for alleles at these loci. Typing of blood DNA can give erroneous results when the animal concerned is a twin; however, this can be overcome by retesting using milk or semen. Analysis of the kappa-casein genotype of Holstein-Friesian bulls gives frequencies for the A and B alleles of 0.80 and 0.20 respectively. Selection in favour of the B allele, which is superior for cheese production, could thus have a large effect. The A3 and B alleles at the beta-casein locus have been shown to be rare in the Holstein-Friesian population. Linkage disequilibrium exists between beta-casein B and kappa-casein B.

  2. Function of ram spermatozoa frozen in diluents supplemented with casein and vegetable oils.

    Science.gov (United States)

    Del Valle, I; Souter, A; Maxwell, W M C; Muiño-Blanco, T; Cebrián-Pérez, J A

    2013-05-01

    The aim of this study was to assess biologically safer components as alternatives to egg yolk for the frozen storage of ram semen using casein, coconut or palm oil in either Salamon's diluent (S) or a swim-up medium (SU). Ejaculates were frozen as pellets and sperm motility (subjectively) and acrosome integrity (FITC-PNA/PI) by flow cytometry were assessed at 0, 3 and 6h after thawing and incubation at 37°C. Three experiments were done: different concentrations of palm oil (5%, 10% and 20%); casein added as emulsifier and protective agent; and differences between egg yolk, coconut and palm oil in S and SU. 20% of oil added to SU accounted for a lesser percentage (Poil levels on viable cells. When casein was added to diluents containing 5% of palm oil, no differences were found between palm or casein (P>0.05). No differences were found when S and SU were compared neither as groups nor between S alone and containing coconut or palm oil; however, SU alone yielded less motility than SU 5% coconut. However, in both groups, S and SU, egg yolk accounted for the greatest values in both bases. These results indicate that none of biologically safer media components (casein, palm or coconut oil) used in this study maintained the function of ram spermatozoa after freeze-thawing better than S-containing egg yolk. The application of vegetable oils as substitutes for egg yolk in diluents for the cryopreservation of ram spermatozoa requires further research.

  3. The membrane-associated form of α(s1-casein interacts with cholesterol-rich detergent-resistant microdomains.

    Directory of Open Access Journals (Sweden)

    Annabelle Le Parc

    Full Text Available Caseins, the main milk proteins, interact with colloidal calcium phosphate to form the casein micelle. The mesostructure of this supramolecular assembly markedly influences its nutritional and technological functionalities. However, its detailed molecular organization and the cellular mechanisms involved in its biogenesis have been only partially established. There is a growing body of evidence to support the concept that α(s1-casein takes center stage in casein micelle building and transport in the secretory pathway of mammary epithelial cells. Here we have investigated the membrane-associated form of α(s1-casein in rat mammary epithelial cells. Using metabolic labelling we show that α(s1-casein becomes associated with membranes at the level of the endoplasmic reticulum, with no subsequent increase at the level of the Golgi apparatus. From morphological and biochemical data, it appears that caseins are in a tight relationship with membranes throughout the secretory pathway. On the other hand, we have observed that the membrane-associated form of α(s1-casein co-purified with detergent-resistant membranes. It was poorly solubilised by Tween 20, partially insoluble in Lubrol WX, and substantially insoluble in Triton X-100. Finally, we found that cholesterol depletion results in the release of the membrane-associated form of α(s1-casein. These experiments reveal that the insolubility of α(s1-casein reflects its partial association with a cholesterol-rich detergent-resistant microdomain. We propose that the membrane-associated form of α(s1-casein interacts with the lipid microdomain, or lipid raft, that forms within the membranes of the endoplasmic reticulum, for efficient forward transport and sorting in the secretory pathway of mammary epithelial cells.

  4. Effect of Fatty acids and beeswax addition on properties of sodium caseinate dispersions and films.

    Science.gov (United States)

    Fabra, M J; Jiménez, A; Atarés, L; Talens, P; Chiralt, A

    2009-06-08

    Edible films based on sodium caseinate and different saturated fatty acids, oleic acid, or beeswax were formulated. Film-forming emulsions were characterized in terms of particle size distribution, rheological behavior and surface tension. In order to evaluate the influence of lipids on sodium caseinate matrices, mechanical, optical, and water vapor barrier properties were studied, taking into account the effect of water content and film structure on such properties. Saturated fatty acids affected the film properties in a particular way due to the formation of bilayer structures which limited water vapor permeability, giving rise to nonflexible and more opaque films. Oleic acid and beeswax were less effective as water vapor barriers, although the former imparted more flexibility to the caseinate films and did not reduce the film transparency notably.

  5. Chaperone-Like Activity of ß-Casein and Its Effect on Residual in Vitro Activity of Food Enzymes

    DEFF Research Database (Denmark)

    Sulewska, Anna Maria

    Agaricus bisporus and equine cytochrome c. Only for the first target β-casein was acting as a molecular chaperone i.e. its presence resulted in higher residual activity (higher degree of the function preservation). β-Casein did not have any influence on the residual activity of tyrosinase. Surprisingly...

  6. Identification of casein as the major allergenic and antigenic protein of cow's milk.

    Science.gov (United States)

    Docena, G H; Fernandez, R; Chirdo, F G; Fossati, C A

    1996-06-01

    The objective of this study was to analyze both the allergenicity and immunogenicity of cow's milk proteins. To this end, 80 milk-atopic patients were selected on the basis of the presence of cow's milk-specific IgE antibodies in serum and compatible clinical history. Fifteen patients allergic to other allergens and 10 nonatopic subjects were studied as controls. The specificity of serum IgG and IgE antibodies was determined by immunoblotting, employing both cow's milk and milk components, i.e., alpha- and beta-casein, beta-lactoglobulin, and alpha-lactalbumin separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The experiments showed that casein-specific IgE antibodies were present in all (80/80) sera examined; 10/80 showed reactivity to beta-lactoglobulin, and 5/80 showed reactivity to alpha-lactalbumin. None of the 25 negative control sera analyzed showed the presence of specific IgE antibodies against milk proteins. These results were similar to those corresponding to the detection, by the radioallergosorbent test, of IgE antibodies against the milk components coupled to paper disks. All sera from milk-atopic patients also showed IgE reactivity against a high-molecular-mass fraction that hardly enters the gel. This fraction, after separation by gel filtration and treatment with beta-mercaptoethanol and urea, was shown by SDS-PAGE analysis to be formed by casein monomers. All sera analyzed by immunoblotting reacted against the components corresponding to casein monomers. Inhibition of immunoblotting by adsorption with different milk components confirmed that those high-molecular-mass aggregates are formed by casein components. The results presented here strongly suggest that casein is the major allergenic component of cow's milk.

  7. Complexation of sodium caseinate with gum tragacanth: Effect of various species and rheology of coacervates.

    Science.gov (United States)

    Ghorbani Gorji, Sara; Ghorbani Gorji, Elham; Mohammadifar, Mohammad Amin; Zargaraan, Azizollaah

    2014-06-01

    We investigated complex coacervation of sodium caseinate/Astragalus rahensis (A.r) as a function of pH with light scattering, spectrophotometry, and viscosity measurements. Interestingly, sodium caseinate/A.r displayed five structural transitions; pH 7.00 to pH ∼5.40: no interaction occurred, pH ∼5.40 to pH ∼4.80: initiation of the formation of primary soluble complexes, pH ∼4.80 to ∼4.30: formation of interpolymer complexes, pH ∼4.30 to ∼4.02: optimum coacervation and pH ∼4.02 to ∼2.50: suppression of coacervation. In addition, rheological properties of sodium caseinate/A.r coacervates were studied at various pH values. A much higher storage modulus (G') than loss modulus (G″) for all sodium caseinate/A.r coacervates suggests the formation of highly interconnected gel-like network structures with mainly elastic behaviour. Moreover, sodium caseinate/A.r coacervates at all pH values exhibited a shear thinning behaviour across the entire shear rate range investigated. Effects of different species of gum tragacanth on the interactions with sodium caseinate have been scarcely studied. Our study showed that systems containing various species (A.r, soluble fraction of A.r and Astragalus gossypinus (A.g)) had different critical pH values and particle sizes during complex coacervation, which could be due to different ratio of soluble to insoluble fractions and uronic acid content of various species.

  8. Analysis of beta-casein gene (CSN2 polymorphism in different breeds of cattle

    Directory of Open Access Journals (Sweden)

    Martina Miluchová

    2014-11-01

    Full Text Available Normal 0 21 false false false SK X-NONE X-NONE MicrosoftInternetExplorer4 The goal of work was identification of b - casein gene polymorphism in different breeds of cow. The beta - casein constitutes up to 45 % of the casein of bovine milk. The most common forms of beta-casein in dairy cattle breeds are A1 and A2, while B is less common. The b-casein A1 variant was associated with the incidence of diabetes mellitus 1st type, coronary heart disease and autism. The A2 variant reduces serum cholesterol. The material involved 287 cows (Simmental breed – 111 cows, Pinzgau breed – 89 cows, Holstein breed – 87 cows. Bovine genomic DNA was extracted from whole blood by using commercial kit and used in order to estimate b - casein genotypes by means of PCR-RFLP method. In the populations included in the study were detected all three genotypes – homozygote genotype A1A1, heterozygote genotype A1A2 and homozygote genotype A2A2 with frequencies 0.1261, 0.3333 and 0.5405 in Simmental breed; 0.1379, 0.4598 and 0.4023 in Holstein breed, 0.3034, 0.5168 and 0.1798 in Pinzgau breed. In population of Simmental breed and Holstein breed was higher frequency of allele A2 (0.7072 and 0.6322. In opposite, in population of Pinzgau breed was present higher frequency of the allele A1 (0.5618.

  9. Whey or Casein Hydrolysate with Carbohydrate for Metabolism and Performance in Cycling.

    Science.gov (United States)

    Oosthuyse, T; Carstens, M; Millen, A M E

    2015-07-01

    The protein type most suitable for ingestion during endurance exercise is undefined. This study compared co-ingestion of either 15 g/h whey or casein hydrolysate with 63 g/h fructose: maltodextrin (0.8:1) on exogenous carbohydrate oxidation, exercise metabolism and performance. 2 h postprandial, 8 male cyclists ingested either: carbohydrate-only, carbohydrate-whey hydrolysate, carbohydrate-casein hydrolysate or placebo-water in a crossover, double-blind design during 2 h of exercise at 60%W max followed by a 16-km time trial. Data were evaluated by magnitude-based inferential statistics. Exogenous carbohydrate oxidation, measured from (13)CO2 breath enrichment, was not substantially influenced by co-ingestion of either protein hydrolysate. However, only co-ingestion of carbohydrate-casein hydrolysate substantially decreased (98% very likely decrease) total carbohydrate oxidation (mean±SD, 242±44; 258±47; 277±33 g for carbohydrate-casein, carbohydrate-whey and carbohydrate-only, respectively) and substantially increased (93% likely increase) total fat oxidation (92±14; 83±27; 73±19 g) compared with carbohydrate-only. Furthermore, only carbohydrate-casein hydrolysate ingestion resulted in a faster time trial (-3.6%; 90% CI: ±3.2%) compared with placebo-water (95% likely benefit). However, neither protein hydrolysate enhanced time trial performance when compared with carbohydrate-only. Under the conditions of this study, ingesting carbohydrate-casein, but not carbohydrate-whey hydrolysate, favourably alters metabolism during prolonged moderate-strenuous cycling without substantially altering cycling performance compared with carbohydrate-only.

  10. Serotonin suppresses β-casein expression via PTP1B activation in human mammary epithelial cells.

    Science.gov (United States)

    Chiba, Takeshi; Maeda, Tomoji; Sanbe, Atsushi; Kudo, Kenzo

    2016-04-22

    Serotonin (5-hydroxytriptamine, 5-HT) has an important role in milk volume homeostasis within the mammary gland during lactation. We have previously shown that the expression of β-casein, a differentiation marker in mammary epithelial cells, is suppressed via 5-HT-mediated inhibition of signal transduction and activator of transcription 5 (STAT5) phosphorylation in the human mammary epithelial MCF-12A cell line. In addition, the reduction of β-casein in turn was associated with 5-HT7 receptor expression in the cells. The objective of this study was to determine the mechanisms underlying the 5-HT-mediated suppression of β-casein and STAT5 phosphorylation. The β-casein level and phosphorylated STAT5 (pSTAT5)/STAT5 ratio in the cells co-treated with 5-HT and a protein kinase A (PKA) inhibitor (KT5720) were significantly higher than those of cells treated with 5-HT alone. Exposure to 100 μM db-cAMP for 6 h significantly decreased the protein levels of β-casein and pSTAT5 and the pSTAT5/STAT5 ratio, and significantly increased PTP1B protein levels. In the cells co-treated with 5-HT and an extracellular signal-regulated kinase1/2 (ERK) inhibitor (FR180294) or Akt inhibitor (124005), the β-casein level and pSTAT5/STAT5 ratio were equal to those of cells treated with 5-HT alone. Treatment with 5-HT significantly induced PTP1B protein levels, whereas its increase was inhibited by KT5720. In addition, the PTP1B inhibitor sc-222227 increased the expression levels of β-casein and the pSTAT5/STAT5 ratio. Our observations indicate that PTP1B directly regulates STAT5 phosphorylation and that its activation via the cAMP/PKA pathway downstream of the 5-HT7 receptor is involved in the suppression of β-casein expression in MCF-12A cells.

  11. Phosphorylation of acidic ribosomal proteins from rabbit reticulocytes by a ribosome-associated casein kinase

    DEFF Research Database (Denmark)

    Issinger, O G

    1977-01-01

    Two acidic proteins from 80-S ribosomes were isolated and purified to homogeneity. The purified acidic proteins could be phosphorylated by casein kinase using [gamma-32P]ATP and [gamma-32P]GTP as a phosphoryl donor. The proteins became phosphorylated in situ, too. Sodium dodecyl sulfate polyacryl......Two acidic proteins from 80-S ribosomes were isolated and purified to homogeneity. The purified acidic proteins could be phosphorylated by casein kinase using [gamma-32P]ATP and [gamma-32P]GTP as a phosphoryl donor. The proteins became phosphorylated in situ, too. Sodium dodecyl sulfate...

  12. Treatment of post-orthodontic white spot lesions with casein phosphopeptide-stabilised amorphous calcium phosphate

    DEFF Research Database (Denmark)

    Bröchner, Ann; Christensen, Carsten; Kristensen, Bjarne;

    2010-01-01

    This study aims to investigate the effect of topical applications of 10% casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on white spot lesions (WSL) detected after treatment with fixed orthodontic appliances. Sixty healthy adolescents with >/=1 clinically visible WSL at debonding were...... findings were largely reflected by the clinical scores. No side effects were reported. Topical treatment of white spot lesions after debonding of orthodontic appliances with a casein phosphopeptide-stabilised amorphous calcium phosphate agent resulted in significantly reduced fluorescence and a reduced...

  13. Casein addition to a whey-based formula has limited effects on gut function in preterm pigs

    DEFF Research Database (Denmark)

    Thymann, T.; Støy, Ann Cathrine Findal; Bering, S. B.

    2012-01-01

    followed by 30 h of enteral feeding with whey [protein fraction of milk formula based on whey (WHEY); n = 11] or casein and/or whey [protein fraction of milk formula based on a combination of casein and whey (CASEIN); n = 9]-based formulas. Sugar absorptive function was investigated at 6 and 30 h after......Preterm infants are susceptible to necrotizing enterocolitis (NEC). Using preterm pigs, we determined whether a whey–casein-based formula would be superior to a formula based on whey protein alone. Twenty cesarean-derived preterm pigs (92% gestation) were given total parenteral nutrition for 36 h...... studied in gut contents. Severity of NEC lesions was similar between diet groups but galactose absorption was markedly higher in CASEIN than in WHEY (P

  14. Magnetic bead and gold nanoparticle probes based immunoassay for β-casein detection in bovine milk samples.

    Science.gov (United States)

    Li, Y S; Meng, X Y; Zhou, Y; Zhang, Y Y; Meng, X M; Yang, L; Hu, P; Lu, S Y; Ren, H L; Liu, Z S; Wang, X R

    2015-04-15

    In this work, a double-probe based immunoassay was developed for rapid and sensitive determination of β-casein in bovine milk samples. In the method, magnetic beads (MBs), employed as supports for the immobilization of anti-β-casein polyclonal antibody (PAb), were used as the capture probe. Colloidal gold nanoparticles (AuNPs), employed as a bridge for loading anti-β-casein monoclonal antibody (McAb) and horseradish peroxidase (HRP), were used as the amplification probe. The presence of β-casein causes the sandwich structures of MBs-PAb-β-casein-McAb-AuNPs through the interaction between β-casein and the anti-β-casein antibodies. The HRP, used as an enzymatic-amplified tracer, can catalytically oxidize the substrate 3,3',5,5'-tetramethylbenzidine (TMB), generating optical signals that are proportional to the quantity of β-casein. The linear range of the immunoassay was from 6.5 to 1520ngmL(-1). The limit of detection (LOD) was 4.8ngmL(-1) which was 700 times lower than that of MBs-antibody-HRP based immunoassay and 6-7 times lower than that from the microplate-antibody-HRP based assay. The recoveries of β-casein from bovine milk samples were from 95.0% to 104.3% that had a good correlation coefficient (R(2)=0.9956) with those obtained by an official standard Kjeldahl method. For higher sensitivity, simple sample pretreatment and shorter time requirement of the antigen-antibody reaction, the developed immunoassay demonstrated the viability for detection of β-casein in bovine milk samples.

  15. Stimulation of muscle protein synthesis by whey and caseinate ingestion after resistance exercise in elderly individuals

    DEFF Research Database (Denmark)

    Dideriksen, K J; Reitelseder, S; Petersen, S G;

    2011-01-01

    before exercise (CasPre), caseinate intake immediately after exercise (CasPost), whey intake immediately after exercise (Whey), or intake of a non-caloric control drink (Control). Muscle myofibrillar and collagen fractional synthesis rates (FSR) were measured by a primed continuous infusion of L-[1...... protein synthesis (MPS) to intakes of whey and caseinate after heavy resistance exercise in healthy elderly individuals, and, furthermore, to compare the timing effect of caseinate intake. Twenty-four elderly men and women (mean ± SEM; 68 ± 1 years) were randomized to one of four groups: caseinate intake......-(13) C]leucine using labeled proteins during a 6-h recovery period. No differences were observed in muscle myofibrillar and collagen FSR with Whey (0.09 ± 0.01%/h) compared with CasPost (0.09 ± 0.003%/h), and it did not differ between CasPre (0.10 ± 0.01%/h) and CasPost. MPS does not differ with whey...

  16. The balance between caseins and whey proteins in cow's milk determines its allergenicity.

    Science.gov (United States)

    Lara-Villoslada, F; Olivares, M; Xaus, J

    2005-05-01

    Cow's milk allergy is quite common in the first years of human life. Protein composition plays an important role in this pathology, particularly the casein/whey protein ratio. It is known that milks from different species have different sensitization capacities although their protein sources are quite similar. Thus, the objective of this work was to compare the allergenicity of native cow's milk and milk with a modified ratio of casein and whey proteins in a murine model of atopy. Twenty-four Balb/c mice were orally sensitized to native cow's milk or modified cow's milk with a casein/whey protein ratio of 40:60. During the sensitization period, the number of mice suffering from diarrhea was significantly higher in the native cow's milk-sensitized group than in the modified milk-sensitized group. Once mice were killed, plasma histamine levels were shown to be significantly higher in native cow's milk-sensitized mice. In addition, cow's milk proteins induced a higher lymphocyte sensitization in the native milk-sensitized mice, with a significant increase in the specific proliferation ratio of these cells. These results suggest that the balance between caseins and whey proteins plays an important role in the sensitization capacity of cow's milk, and its modification might be a way to reduce the allergenicity of cow's milk.

  17. Cloning and sequencing of the casein kinase 2 alpha subunit from Zea mays

    DEFF Research Database (Denmark)

    Dobrowolska, G; Boldyreff, B; Issinger, O G

    1991-01-01

    The nucleotide sequence of the cDNA coding for the alpha subunit of casein kinase 2 of Zea mays has been determined. The cDNA clone contains an open reading frame of 996 nucleotides encoding a polypeptide comprising 332 amino acids. The primary amino acid sequence exhibits 75% identity to the alpha...

  18. Acid-induced gelation behavior of casein/whey protein solutions assessed by oscillatory rheology.

    Science.gov (United States)

    Sadeghi, Mahboubeh; Madadlou, Ashkan; Khosrowshahi, Asghar; Mohammadifar, Mohammadamin

    2014-09-01

    Gelation process of acid-induced casein gels was studied using response surface method (RSM). Ratio of casein to whey proteins, incubation and heating temperatures were independent variables. Final storage modulus (G') measured 200 min after the addition of glucono-δ-lactone and the gelation time i.e. the time at which G' of gels became greater than 1 Pa were the parameters studied. Incubation temperature strongly affected both parameters. The higher the incubation temperature, the lower was the G' and the shorter the gelation time. Increased heating temperature however, increased the G' but again shortened the gelation time. Increase in G' was attributed to the formation of disulphide cross-linkages between denatured whey proteins and casein chains; whilst the latter was legitimized by considering the higher isoelectric pH of whey proteins. Maximum response (G' = 268.93 Pa) was obtained at 2.7 % w/w, 25 °C and 90 °C for casein content, incubation and heating temperatures, respectively.

  19. The adsorption of lysozyme and chymosin onto emulsion droplets and their association with caseins

    NARCIS (Netherlands)

    Roos, de A.

    1999-01-01

    The proteolytic action of proteases present in cheese plays a major role in the ripening of cheese. These proteases originate from the rennet, the starter cultures and from the milk itself. The proteolysis in cheese results in the degradation of the casein proteins into smaller peptides and free ami

  20. Trichostatin A inhibits beta-casein expression in mammary epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Pujuguet, Philippe; Radisky, Derek; Levy, Dinah; Lacza, Charlemagne; Bissell, Mina J.

    2002-02-22

    Many aspects of cellular behavior are affected by information derived from association of the extracellular matrix (ECM) and with cell membrane receptors. When cultured in the presence of laminin-containing ECM and prolactin (Prl), normal mammary epithelial cells express the milk protein beta-casein. Previously, we defined the minimal ECM- and Prl-responsive enhancer element BCE-1 from the upstream region of the beta-casein gene. We also found that BCE-1 was only active when stably integrated into chromatin, and that trichostatin A (TSA), a reagent that leads to alterations in chromatin structure, was able to activate the integrated enhancer element. We now show that endogenous b-casein gene, which is controlled by a genetic assembly that is highly similar to that of BCE-1 and which is also activated by incubation in ECM and Prl, is instead inhibited by TSA. We provide evidence that the differing response of b-casein and BCE-1 to TSA is neither due to an unusual effect of TSA on mammary epithelial cells, nor to secondary consequences from the expression of a separate gene, nor to a particular property of the BCE-1 construct. As a component of this investigation, we also showed that ECM could mediate rapid histone deacetylation in mammary epithelial cells. These results are discussed in combination with previous work showing that TSA mediates the differentiation of many types of cancer cells but inhibits differentiation of some nonmalignant cell types.

  1. Casein and soybean protein-based thermoplastics and composites as alternative biodegradable polymers for biomedical applications

    NARCIS (Netherlands)

    Vaz, C.M.; Fossen, M.; Tuil, van R.F.; Graaf, de L.A.; Reis, R.L.; Cunha, A.M.

    2003-01-01

    This work reports on the development and characterization of novel meltable polymers and composites based on casein and soybean proteins. The effects of inert (Al2O3) and bioactive (tricalcium phosphate) ceramic reinforcements over the mechanical performance, water absorption, and bioactivity behavi

  2. Effects of structural rearrangements on the rheology of rennet-induced casein particle gels

    NARCIS (Netherlands)

    Mellema, M.; Walstra, P.; Opheusden, van J.H.J.; Vliet, van T.

    2002-01-01

    During ageing of casein or skim milk gels, structural changes take place that affect gel parameters, such as pore size and storage modulus. These changes can be explained in terms of rearrangements of the gel network at various length scales. In this paper, rheological experiments on rennet-induced

  3. The influence of casein and urea as nitrogen sources on in vitro equine caecal fermentation

    NARCIS (Netherlands)

    Santos, A.S.; Ferreira, L.M.M.; Martin-Rosset, W.; Cotovio, M.; Silva, F.; Bennett, R.N.; Cone, J.W.; Bessa, R.J.B.; Rodrigues, M.A.M.

    2012-01-01

    To access the fermentative response of equine caecal microbial population to nitrogen availability, an in vitro study was conducted using caecal contents provided with adequate energy sources and nitrogen as limiting nutrient. Two nitrogen (N) sources were provided, protein (casein) and non-protein

  4. Ultrasound effects on the assembly of casein micelles in reconstituted skim milk.

    Science.gov (United States)

    Liu, Zheng; Juliano, Pablo; Williams, Roderick P W; Niere, Julie; Augustin, Mary Ann

    2014-05-01

    Reconstituted skim milks (10 % w/w total solids, pH 6·7-8·0) were ultrasonicated (20, 400 or 1600 kHz at a specific energy input of 286 kJ/kg) at a bulk milk temperature of <30 °C. Application of ultrasound to milk at different pH altered the assembly of the casein micelle in milk, with greater effects at higher pH and lower frequency. Low frequency ultrasound caused greater disruption of casein micelles causing release of protein from the micellar to the serum phase than high frequency. The released protein re-associated to form aggregates of smaller size but with surface charge similar to the casein micelles in the original milk. Ultrasound may be used as a physical intervention to alter the size of the micelles and the partitioning of caseins between the micellar and serum phases in milk. The altered protein equilibria induced by ultrasound treatment may have potential for the development of milk with novel functionality.

  5. Divergence at the casein haplotypes in dairy and meat goat breeds.

    Science.gov (United States)

    Küpper, Julia; Chessa, Stefania; Rignanese, Daniela; Caroli, Anna; Erhardt, Georg

    2010-02-01

    Casein genes have been proved to have an influence on milk properties, and are in addition appropriate for phylogeny studies. A large number of casein polymorphisms exist in goats, making their analysis quite complex. The four casein loci were analyzed by molecular techniques for genetic polymorphism detection in the two dairy goat breeds Bunte Deutsche Edelziege (BDE; n=96), Weisse Deutsche Edelziege (WDE; n=91), and the meat goat breed Buren (n=75). Of the 35 analyzed alleles, 18 were found in BDE, and 17 in Buren goats and WDE. In addition, a new allele was identified at the CSN1S1 locus in the BDE, showing a frequency of 0.05. This variant, named CSN1S1*A', is characterized by a t-->c transversion in intron 9. Linkage disequilibrium was found at the casein haplotype in all three breeds. A total of 30 haplotypes showed frequencies higher than 0.01. In the Buren breed only one haplotype showed a frequency higher than 0.1. The ancestral haplotype B-A-A-B (in the order: CSN1S1-CSN2-CSN1S2-CSN3) occurred in all three breeds, showing a very high frequency (>0.8) in the Buren.

  6. The Gluten-Free, Casein-Free Diet and Autism: Limited Return on Family Investment

    Science.gov (United States)

    Hurwitz, Sarah

    2013-01-01

    The gluten-free, casein-free (GFCF) diet is widely used by families of children with autism spectrum disorders (ASD). Despite its popularity, there is limited evidence in support of the diet. The purpose of this article was to identify and evaluate well-controlled studies of the GFCF diet that have been implemented with children with ASD. A review…

  7. Properties of acid casein gels made by acidification with Glucono-δ-lactone. 1. Rheological properties

    NARCIS (Netherlands)

    Lucey, J.A.; Vliet, van T.; Grolle, K.; Geurts, T.; Walstra, P.

    1997-01-01

    The effects of gelation temperature (20, 30 or 40 °C), assay temperature, concentration of glucono-δ-lactone (GDL) added, and NaCl concentration on the rheological properties of acid casein gels were studied at small and large deformations. Gels prepared at a high incubation temperature had very low

  8. Phosphorylation of nm23/nucleoside diphosphate kinase by casein kinase 2 in vitro

    DEFF Research Database (Denmark)

    Engel, M; Issinger, O G; Lascu, I;

    1994-01-01

    We have investigated phosphorylation of human nucleoside diphosphate kinase (NDPK) and of homologous NDPK from different species by human casein kinase 2 (CK-2). The human NDPK isotypes A and B were phosphorylated by CK-2 in vitro both when the purified proteins and total lysate of HL-60 leukemia...

  9. Reconstitution of normal and hyperactivated forms of casein kinase-2 by variably mutated beta-subunits

    DEFF Research Database (Denmark)

    Boldyreff, B; Meggio, F; Pinna, L A;

    1993-01-01

    Twenty-one mutants of the noncatalytic beta-subunit of human casein kinase-2 have been created, expressed in Escherichia coli, and purified to homogeneity. They are either modified at the autophosphorylation site (mutants beta delta 1-4 and beta A 5,6) or bear variable deletions in their C...

  10. Caseins from bovine colostrum and milk strongly bind piscidin-1, an antimicrobial peptide from fish.

    Science.gov (United States)

    Kütt, Mary-Liis; Stagsted, Jan

    2014-09-01

    A model system of bovine colostrum and piscidin, a fish-derived antimicrobial peptide, was developed to study potential interactions of antimicrobial peptides in colostrum. We did not detect any antimicrobial activity of colostrum using the radial plate diffusion assay; in fact colostrum completely abrogated activity of added piscidin. This could not be explained by degradation of piscidin by colostrum, which was less than ten percent. We found that colostrum even protected piscidin against degradation by added proteases. We further observed that colostrum and milk rapidly quenched the fluorescence of fluorescein-piscidin but not that of fluorescein. This effect was not seen with BSA and the specific quenching of fluorescein-piscidin by colostrum was saturably inhibited with unlabeled piscidin. Size exclusion chromatography indicated that fluorescein-piscidin bound to casein micelles with no apparent binding to IgG or whey proteins. Further, addition of pure caseins was able to quench fluorescence of fluorescein-piscidin and to inhibit the antimicrobial activity of piscidin. The interaction between caseins and piscidin could be dissociated by guanidine hydrochloride and recovered piscidin had antimicrobial activity against bacteria. Based on our results we propose that caseins could be carriers for antimicrobial peptides in colostrum and milk.

  11. Analysis of the endogenous peptide profile of milk: identification of 248 mainly casein-derived peptides.

    Science.gov (United States)

    Baum, Florian; Fedorova, Maria; Ebner, Jennifer; Hoffmann, Ralf; Pischetsrieder, Monika

    2013-12-06

    Milk is an excellent source of bioactive peptides. However, the composition of the native milk peptidome has only been partially elucidated. The present study applied matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) directly or after prefractionation of the milk peptides by reverse-phase high-performance liquid chromatography (RP-HPLC) or OFFGEL fractionation for the comprehensive analysis of the peptide profile of raw milk. The peptide sequences were determined by MALDI-TOF/TOF or nano-ultra-performance liquid chromatography-nanoelectrospray ionization-LTQ-Orbitrap-MS. Direct MALDI-TOF-MS analysis led to the assignment of 57 peptides. Prefractionation by both complementary methods led to the assignment of another 191 peptides. Most peptides originate from α(S1)-casein, followed by β-casein, and α(S2)-casein. κ-Casein and whey proteins seem to play only a minor role as peptide precursors. The formation of many, but not all, peptides could be explained by the activity of the endogenous peptidases, plasmin or cathepsin D, B, and G. Database searches revealed the presence of 22 peptides with established physiological function, including those with angiotensin-converting-enzyme (ACE) inhibitory, immunomodulating, or antimicrobial activity.

  12. Interfacial properties, thin film stability and foam stability of casein micelle dispersions

    NARCIS (Netherlands)

    Chen, Min; Sala, G.; Meinders, M.B.J.; Valenberg, van H.J.F.; Linden, van der E.; Sagis, L.M.C.

    2017-01-01

    Foam stability of casein micelle dispersions (CMDs) strongly depends on aggregate size. To elucidate the underlying mechanism, the role of interfacial and thin film properties was investigated. CMDs were prepared at 4 °C and 20 °C, designated as CMD4 °C and CMD20 °C. At equal protein concentrations,

  13. Impact of Casein and Gluten Free Dietary Intervention on Selected Autistic Children

    Directory of Open Access Journals (Sweden)

    Veerappan Nishadevi

    2008-09-01

    Full Text Available Objective: Autism is a life long developmental disorder that emerges in early childhood and results in significant lifelong disability. The goal of treatment is to promote the childs social and language development and minimize behaviors that interfere with the childs functioning and learning. This study evaluated the impact of casein and gluten free diet among selected autistic children. Methods: Three private special schools in Salem District, Tamilnadu, India were selected. A total number of 50 autistic children 10 from SIMEC, 10 from MMIC and 30 from CSI comprised the study sample. Background information, clinical history and nutritional status, dietary pattern were collected from the 50 selected autistic children. Out of 50 autistic children 30 autistic children were selected for the dietary intervention. Diet counseling regarding casein free diet was imparted to Group I (n=10, gluten free diet to Group II (n=10 and both casein and gluten free diet for Group III (n=10. The diet was followed for a period of 2 months. The efficacy of the dietary exclusion of casein and gluten was evaluated using a food and behavior diary on a day to day basis, using observation method. Findings: Results about Group I autistic children who followed dietary exclusion of casein free diet showed that the mean scores before and after casein free dietary intervention depiticted these improvements as, 1 to 1.2 for attention, 2.8 to 2.9 for sleep, 1.1 to 1.3 for hyperactivity, 1.1 to 1.2 for anxiety/compulsion. For Group II autistic children who followed dietary exclusion of gluten free diet showed the improvements as 1.1 to 1.4 for attention 2.5 to 3 for sleep, 1.7 to 1.9 for hyperactivity, 1.1 to 1.2 for anxiety/compulsion. About Group III autistic children who followed dietary exclusion of both casein and gluten free diet showed the improvements as 1.1 to 1.3 for attention, 2.5 to 2.7 for sleep, 1.3 to 1.7 for hyperactivity, and 1.1 to 1.2 for anxiety

  14. Relative efficacy of casein or soya protein combined with palm or safflower-seed oil on hyperuricaemia in rats.

    Science.gov (United States)

    Lo, Hui-Chen; Wang, Yao-Horng; Chiou, Hue-Ying; Lai, Shan-Hu; Yang, Yu

    2010-07-01

    Diets that ameliorate the adverse effects of uric acid (UA) on renal damage deserve attention. The effects of casein or soya protein combined with palm or safflower-seed oil on various serum parameters and renal histology were investigated on hyperuricaemic rats. Male Wistar rats administered with oxonic acid and UA to induce hyperuricaemia were fed with casein or soya protein plus palm- or safflower-seed oil-supplemented diets. Normal rats and hyperuricaemic rats with or without allopurinol treatment (150 mg/l in drinking water) were fed with casein plus maize oil-supplemented diets. After 8 weeks, allopurinol treatment and soya protein plus safflower-seed oil-supplemented diet significantly decreased serum UA in hyperuricaemic rats (one-way ANOVA; P soya protein and casein attenuated hyperuricaemia-induced decreases in serum albumin and insulin, respectively (two-way ANOVA; P soya protein significantly decreased renal NO and nitrotyrosine and palm oil significantly decreased renal nitrotyrosine, TNF-alpha and interferon-gamma and increased renal transforming growth factor-beta. Casein with safflower-seed oil significantly attenuated renal tubulointerstitial nephritis, crystals and fibrosis. Comparing casein v. soya protein combined with palm or safflower-seed oil, the results support that casein with safflower-seed oil may be effective in attenuating hyperuricaemia-associated renal damage, while soya protein with safflower-seed oil may be beneficial in lowering serum UA and TAG.

  15. Purification and characterization of a casein kinase 2-type protein kinase from pea nuclei

    Science.gov (United States)

    Li, H.; Roux, S. J.

    1992-01-01

    Almost all the polyamine-stimulated protein kinase activity associated with the chromatin fraction of nuclei purified from etiolated pea (Pisum sativum L.) plumules is present in a single enzyme that can be extracted from chromatin by 0.35 molar NaCl. This protein kinase can be further purified over 2000-fold by salt fractionation and anion-exchange and casein-agarose column chromatography, after which it is more than 90% pure. The purified kinase has a specific activity of about 650 nanomoles per minute per milligram protein in the absence of polyamines, with either ATP or GTP as phosphoryl donor. Spermidine can stimulate its activity fourfold, with half-maximal activation at about 2 millimolar. Spermine and putrescine also stimulate activity, although somewhat less effectively. This kinase has a tetrameric alpha 2 beta 2 structure with a native molecular weight of 130,000, and subunit molecular weights of 36,000 for the catalytic subunit (alpha) and 29,000 for the regulatory subunit (beta). In western blot analyses, only the alpha subunit reacts strongly with polyclonal antibodies to a Drosophila casein kinase II. The pea kinase can use casein and phosvitin as artificial substrates, phosphorylating both the serine and threonine residues of casein. It has a pH optimum near 8.0, a Vmax of 1.5 micromoles per minute per milligram protein, and a Km for ATP of approximately 75 micromolar. Its activity can be almost completely inhibited by heparin at 5 micrograms per milliliter, but is relatively insensitive to concentrations of staurosporine, K252a, and chlorpromazine that strongly antagonize Ca(2+) -regulated protein kinases. These results are discussed in relation to recent findings that casein kinase 2-type kinases may phosphorylate trans-acting factors that bind to light-regulated promoters in plants.

  16. Characterization of casein gene complex and genetic diversity analysis in Indian goats.

    Science.gov (United States)

    Rout, P K; Kumar, A; Mandal, A; Laloe, D; Singh, S K; Roy, R

    2010-04-01

    Milk protein polymorphism plays an important role in genetic diversity analysis, phylogenetic studies, establishing geographical diversity, conservation decision, and improving breeding goals. Milk protein polymorphism in Indian goat breeds has not been well studied; therefore, an investigation was carried out to analyze the genetic structure of the casein gene and milk protein diversity at six milk protein loci in nine Indian goat breeds/genetic groups from varied agro-climatic zones. Milk protein genotyping was carried out in 1098 individual milk samples by SDS-PAGE at alphaS1-CN (CSN1S1), beta-CN (CSN2), alphaS2-CN (CSN1S2), kappa-CN (CSN3), beta-LG, and alpha-LA loci. Indian goats exhibited alphaS1-casein A allele in higher frequency in the majority of breeds except Ganjam and local goats. The alphaS1-casein A allele frequencies varied from 0.45 to 0.77. A total of 16 casein haplotypes were observed in seven breeds and breed specific haplotypes were observed with respect to geographic region. The average number of alleles was lowest in Ganjam (1.66 +/- 0.81) and highest in Sirohi goats (2.50 +/- 1.05). Expected heterozygosity at six different loci demonstrated genetic diversity and breed fragmentation. Neighbor-Joining tree was built basing on Nei's distance. There was about 16.95% variability due to differences between breeds, indicating a strong subdivision. Principal component analysis was carried out to highlight the relationship among breeds. The variability among goat breeds was contributed by alphaS2-CN, beta-LG and alphaS1-CN. The Indian goats exhibited alphaS1-CN (CSN1S1) A allele in higher frequency in all the breeds indicating the higher casein yield in their milk.

  17. Identification of protein tyrosine phosphatase 1B and casein as substrates for 124-v-Mos

    Directory of Open Access Journals (Sweden)

    Stabel Silvia

    2002-04-01

    Full Text Available Abstract Background The mos proto-oncogene encodes a cytoplasmic serine/threonine-specific protein kinase with crucial function during meiotic cell division in vertebrates. Based on oncogenic amino acid substitutions the viral derivative, 124-v-Mos, displays constitutive protein kinase activity and functions independent of unknown upstream effectors of mos protein kinase. We have utilized this property of 124-v-Mos and screened for novel mos substrates in immunocomplex kinase assays in vitro. Results We generated recombinant 124-v-Mos using the baculovirus expression system in Spodoptera frugiperda cells and demonstrated constitutive kinase activity by the ability of 124-v-Mos to auto-phosphorylate and to phosphorylate vimentin, a known substrate of c-Mos. Using this approach we analyzed a panel of acidic and basic substrates in immunocomplex protein kinase assays and identified novel in vitro substrates for 124-v-Mos, the protein tyrosine phosphatase 1B (PTP1B, alpha-casein and beta-casein. We controlled mos-specific phosphorylation of PTP1B and casein in comparative assays using a synthetic kinase-inactive 124-v-Mos mutant and further, tryptic digests of mos-phosphorylated beta-casein identified a phosphopeptide specifically targeted by wild-type 124-v-Mos. Two-dimensional phosphoamino acid analyses showed that 124-v-mos targets serine and threonine residues for phosphorylation in casein at a 1:1 ratio but auto-phosphorylation occurs predominantly on serine residues. Conclusion The mos substrates identified in this study represent a basis to approach the identification of the mos-consensus phosphorylation motif, important for the development of specific inhibitors of the Mos protein kinase.

  18. Effect of Fluoride, Casein Phosphopeptide–Amorphous Calcium Phosphate and Casein Phosphopeptide–Amorphous Calcium Phosphate Fluoride on Enamel Surface Microhardness After Microabrasion: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Ghazaleh Ahmadi Zenouz

    2016-03-01

    Full Text Available Objectives: This study aimed to assess the effect of applying casein phosphopeptide–amorphous calcium phosphate (CPP-ACP paste, casein phosphopeptide–amorphous calcium phosphate fluoride (CPP-ACPF paste and sodium fluoride gel on surface microhardness of enamel after microabrasion.Materials and Methods: Thirty freshly extracted human premolars were selected. All samples were subjected to hardness indentations made with the Vickers hardness machine and the average value was recorded as the initial surface microhardness. The specimens were then randomly divided into three groups (n=10 of CPP-ACPF, fluoride and CPP-ACP. The teeth were micro-abraded with Opalustre. Microhardness test was performed to assess the post-abrasion hardness. Three remineralization modalities were performed on samples of each group. The enamel surface microhardness measurements were performed. To compare the difference between groups, the rehardening and softening values were defined. One-way ANOVA and Tukey’s post hoc test at a significance level of 5% were used for statistical analysis.Results: The mean microhardness value (MMV had a significant decrease after microabrasion from baseline. The MMV had a significant increase after remineralization in all groups. The MMV of CPP-ACPF group was significantly more than that of fluoride group (P=0.027. The rehardening value of fluoride group was significantly more than that of other groups (P<0.001.Conclusion: All the remineralizing agents were effective for rehardening the enamel after microabrasion. The CPP-ACP and CPP-ACPF pastes are effective, but to a lesser extent than neutral sodium fluoride gel in remineralizing enamel surface. Incorporation of fluoride to CPP-ACP formulation does not provide any additional remineralizing potential.Keywords: Casein phosphopeptide-amorphous calcium phosphate nanocomplex; Enamel Microabrasion; Hardness; Sodium Fluoride

  19. Effect of spray drying on the sensory and physical properties of hydrolysed casein using gum arabic as the carrier.

    Science.gov (United States)

    Subtil, S F; Rocha-Selmi, G A; Thomazini, M; Trindade, M A; Netto, F M; Favaro-Trindade, C S

    2014-09-01

    This study was aimed at spray drying hydrolysed casein using gum Arabic as the carrier agent, in order to decrease the bitter taste. Three formulations with differing proportions of hydrolysed casein: gum Arabic (10:90, 20:80 and 30:70) were prepared and characterized. They were evaluated for their moisture content, water activity, hygroscopicity, dispersibility in water and in oil, particle size and distribution, particle morphology, thermal behaviour (DSC) and bitter taste by a trained sensory panel using a paired-comparison test (free samples vs. spray dried samples). The proportion of hydrolysed casein did not affect the morphology of the microspheres. The spray drying process increased product stability and modified the dissolution time, but had no effect on the ability of the material to dissolve in either water or oil. The sensory tests showed that the spray drying process using gum Arabic as the carrier was efficient in attenuating or masking the bitter taste of the hydrolysed casein.

  20. Casein addition to a whey-based formula has limited effects on gut function in preterm pigs.

    Science.gov (United States)

    Thymann, T; Støy, C A F; Bering, S B; Mølbak, L; Sangild, P T

    2012-12-01

    Preterm infants are susceptible to necrotizing enterocolitis (NEC). Using preterm pigs, we determined whether a whey-casein-based formula would be superior to a formula based on whey protein alone. Twenty cesarean-derived preterm pigs (92% gestation) were given total parenteral nutrition for 36 h followed by 30 h of enteral feeding with whey [protein fraction of milk formula based on whey (WHEY); n = 11] or casein and/or whey [protein fraction of milk formula based on a combination of casein and whey (CASEIN); n = 9]-based formulas. Sugar absorptive function was investigated at 6 and 30 h after initiation of enteral feeding using bolus feedings with galactose and mannitol. Pigs were killed after the last in vivo sugar absorption test and evaluated for NEC and the mid intestine was used for ex vivo measurements of hexose absorption. Microbiota profile and short chain fatty acid (SCFA) levels were studied in gut contents. Severity of NEC lesions was similar between diet groups but galactose absorption was markedly higher in CASEIN than in WHEY (P SCFA concentration. Casein may transiently stimulate intestinal sugar absorption but has limited effects on gut structure, microbiota, and NEC in preterm pigs.

  1. Moleculer analysis of genotype kappa casein and composition of goat milk Etawah grade, Saanen and their crossbred

    Directory of Open Access Journals (Sweden)

    Yayu Zurriyati

    2011-03-01

    Full Text Available Polymorphism of goat casein gene closely linked to the quality of milk protein. κ-casein is one of the casein fractions that influence the shape and stability of grain milk. This study is aimed to identify the variation of genotype κ-casein and related with milk quality from Etawah grade, Saanen and their crossbreed (PE-SA. The number of dairy goats used in this study was 150 animals consisted of Etawah grade (48 animals, Saanen (51 animals and PE-SA (51 animals. Steps of experiment were: blood and milk sampling collection, DNA amplification by PCR and the product digestion using Pst1 enzyme, κ-casein gene sequencing and analyzing the quality of fresh milk. The results showed that κ-casein gene is monomorphic by PCR-RFLP (Pst1 for all the goat breeds, but DNA sequencing indicated 38 point of mutation. Observation on goat milk quality showed that Etawah grade milk had highest (P < 0.05 density value (1.033 ± 0.002 and solid non fat (9.577 ± 0.704% than those of Saanen and PE-SA fresh milk goat.

  2. Estimation of whey protein in casein coprecipitate and milk powder by high-performance liquid chromatography quantification of cysteine.

    Science.gov (United States)

    Ballin, Nicolai Z

    2006-06-14

    An analytical high-performance liquid chromatography (HPLC)-fluorescence method for indirect measuring of whey protein in casein coprecipitate and milk powder was developed. Samples were hydrolyzed with HCl, and cysteyl residues were derivatized with 3,3'-dithiodipropionic acid and 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate. The cysteine content was used to calculate the percentage of whey protein in commercial samples with use of European Union Regulation cysteine reference values in both casein and whey protein. Method validation studies were performed for caseinates and milk powder, and results indicate that the present HPLC approach can be applied as a fast method with a standard deviation of repeatability between 3.3 and 9.5%. Applicability was studied by analysis of 40 commercial caseinate samples, and all complied to European legislation with a content of whey protein not exceeding 5%. Finally, an approach used to estimate the cysteine amount in pure casein by comparison of calculated and experimental values questions the generally accepted cysteine reference value in casein, which is most likely an overestimation.

  3. Interfacial properties, thin film stability and foam stability of casein micelle dispersions.

    Science.gov (United States)

    Chen, Min; Sala, Guido; Meinders, Marcel B J; van Valenberg, Hein J F; van der Linden, Erik; Sagis, Leonard M C

    2017-01-01

    Foam stability of casein micelle dispersions (CMDs) strongly depends on aggregate size. To elucidate the underlying mechanism, the role of interfacial and thin film properties was investigated. CMDs were prepared at 4°C and 20°C, designated as CMD4°C and CMD20°C. At equal protein concentrations, foam stability of CMD4°C (with casein micelle aggregates) was markedly higher than CMD20°C (without aggregates). Although the elastic modulus of CMD4°C was twice as that of CMD20°C at 0.005Hz, the protein adsorbed amount was slightly higher for CMD20°C than for CMD4°C, which indicated a slight difference in interfacial composition of the air/water interface. Non-linear surface dilatational rheology showed minor differences between mechanical properties of air/water interfaces stabilized by two CMDs. These differences in interfacial properties could not explain the large difference in foam stability between two CMDs. Thin film analysis showed that films made with CMD20°C drained to a more homogeneous film compared to films stabilized by CMD4°C. Large casein micelle aggregates trapped in the thin film of CMD4°C made the film more heterogeneous. The rupture time of thin films was significantly longer for CMD4°C (>1h) than for CMD20°C (foam stability decreased significantly. In conclusion, the increased stability of foam prepared with CMD4°C appears to be the result of entrapment of casein micelle aggregates in the liquid films of the foam.

  4. How to Squeeze a Sponge: Casein Micelles under Osmotic Stress, a SAXS Study

    OpenAIRE

    Bouchoux, Antoine; Gésan-Guiziou, Geneviève; Pérez, Javier; Cabane, Bernard

    2010-01-01

    By combining the osmotic stress technique with small-angle x-ray scattering measurements, we followed the structural response of the casein micelle to an overall increase in concentration. When the aqueous phase that separates the micelles is extracted, they behave as polydisperse repelling spheres and their internal structure is not affected. When they are compressed, the micelles lose water and shrink to a smaller volume. Our results indicate that this compression is nonaffine, i.e., some p...

  5. Gluten-free and casein-free diets in the treatment of autism

    OpenAIRE

    Andreas Reissmann; Joachim Hauser; Ewelina Makulska-Gertruda; Loredana Tomsa; Lange, Klaus W.

    2014-01-01

    Background: Autism is a complex psychiatric disorder characterized by three core symptoms, i.e. impairments in social interaction, restricted patterns of behavior and impairments in communication. In the framework of the “opioid excess theory”, the disorder symptoms are compared to the behavioral effects of opiates. Based on this, a possible nutritional basis of autism has been proposed, hypothesizing that certain food proteins such as gluten and casein can be transformed ...

  6. A review of gluten- and casein-free diets for treatment of autism: 2005–2015

    OpenAIRE

    Elder, Jennifer; Kreider, Consuelo; Schaefer, Nancy; deLaosa,Mary

    2015-01-01

    Jennifer Harrison Elder,1 Consuelo Maun Kreider,2 Nancy M Schaefer,3 Mary B de Laosa4 1Department of Family and Community Health Nursing Science, 2Department of Occupational Therapy, 3Health Science Center Library, 4Department of Psychology, University of Florida, Gainesville, FL, USA Background: The gluten-free, casein-free (GFCF) diet is heralded by strong anecdotal parental reports to greatly improve and even "cure" symptoms of autism spectrum disorders (ASDs). Yet, to d...

  7. A review of gluten- and casein-free diets for treatment of autism: 2005–2015

    OpenAIRE

    Elder JH; Kreider CM; Schaefer NM; de Laosa MB

    2015-01-01

    Jennifer Harrison Elder,1 Consuelo Maun Kreider,2 Nancy M Schaefer,3 Mary B de Laosa4 1Department of Family and Community Health Nursing Science, 2Department of Occupational Therapy, 3Health Science Center Library, 4Department of Psychology, University of Florida, Gainesville, FL, USA Background: The gluten-free, casein-free (GFCF) diet is heralded by strong anecdotal parental reports to greatly improve and even "cure" symptoms of autism spectrum disorders (ASDs). Yet, to date, lit...

  8. Kappa-casein gene study in Iranian Sistani cattle breed (Bos indicus) using PCR-RFLP.

    Science.gov (United States)

    Rohallah, Alinaghizadeh; Mohammadreza, Mohammad Abadi; Shahin, Moradnasab Badrabadi

    2007-12-01

    In cattle, caseins are subdivided into four main groups: alphaS1-, alphaaS2-, beta- and kappa-caseins. kappa-caseins (CSN2) considerably differ from other caseins in structure and other properties. Testing the A and B alleles is of practical importance, because the milk of cows that carry the B allele of CSN3 has a better thermal resistance and shorter coagulation time, better curdles and contains micelles of different sizes. Iranian Sistani cattle (Bos indicus) are a heavy built breed and used as dual-purpose cattle breed in Eastern Iran. This breed is a genetic resource that shows special features of adaptation to rustic environments. One of the most distinctive features of Sistani cattle is its great capability to resist diseases which makes it a potential reservoir of germplasm useful for future crosses. Our main goal was to study DNA-polymorphism of the CSN3 gene in the Iranian Sistani native cattle (Bos indicus) and analyze the information value of CSN3 gene polymorphism as a genetic marker. We genotyped and analyzed 65 animals of this breed using PCR-RFLP. The frequencies of A and B alleles were 0.6385 and 0.3615 and those of AA, AB and BB genotypes were 0.4000, 0.4769 and 0.1231, respectively. In the Sistani Zebu breed, frequency of B allele is higher than other Zebu breeds, indicating that intensive selection for dairy production have been done and indirectly influenced CSN3 allele frequencies.

  9. Short communication: genetic variability in the predicted microRNA target sites of caprine casein genes.

    Science.gov (United States)

    Zidi, A; Amills, M; Tomás, A; Vidal, O; Ramírez, O; Carrizosa, J; Urrutia, B; Serradilla, J M; Clop, A

    2010-04-01

    The main goal of the current work was to identify single nucleotide polymorphisms (SNP) that might create or disrupt microRNA (miRNA) target sites in the caprine casein genes. The 3' untranslated regions of the goat alpha(S1)-, alpha(S2)-, beta-, and kappa-casein genes (CSN1S1, CSN1S2, CSN2, and CSN3, respectively) were resequenced in 25 individuals of the Murciano-Granadina, Cashmere, Canarian, Saanen, and Sahelian breeds. Five SNP were identified through this strategy: c.175C>T at CSN1S1; c.109T>C, c.139G>C, and c.160T>C at CSN1S2; and c.216C>T at CSN2. Analysis with the Patrocles Finder tool predicted that all of these SNP are located within regions complementary to the seed of diverse miRNA sequences. These in silico results suggest that polymorphism at miRNA target sites might have some effect on casein expression. We explored this issue by genotyping the c.175C>T SNP (CSN1S1) in 85 Murciano-Granadina goats with records for milk CSN1S1 concentrations. This substitution destroys a putative target site for miR-101, a miRNA known to be expressed in the bovine mammary gland. Although TT goats had higher levels (6.25 g/L) of CSN1S1 than their CT (6.05 g/L) and CC (6.04 g/L) counterparts, these differences were not significant. Experimental confirmation of the miRNA target sites predicted in the current work and performance of additional association analyses in other goat populations will be an essential step to find out if polymorphic miRNA target sites constitute an important source of variation in casein expression.

  10. K-酪蛋白研究进展%Research on k-casein: A review

    Institute of Scientific and Technical Information of China (English)

    刘文静; 郑玉才; 钟光辉

    2001-01-01

    对k-酪蛋白(kappa-casein,k-CN)的基本特征,遗传多态性及其与乳成分、凝乳性能的关系,以及k-CN定型技术作了综述;并探讨了k-CN遗传多态性在乳酪生产和牦牛育种中的应用前景.

  11. Galactose content of legumes, caseinates, and some hard cheeses: implications for diet treatment of classic galactosemia.

    Science.gov (United States)

    Van Calcar, Sandra C; Bernstein, Laurie E; Rohr, Frances J; Yannicelli, Steven; Berry, Gerard T; Scaman, Christine H

    2014-02-12

    There are inconsistent reports on the lactose and/or galactose content of some foods traditionally restricted from the diet for classic galactosemia. Therefore, samples of cheeses, caseinates, and canned black, pinto, kidney, and garbanzo beans were analyzed for free galactose content using HPLC with refractive index or pulsed amperometric detection. Galactose concentrations in several hard and aged cheeses and three mild/medium Cheddars, produced by smaller local dairies, was galactosemia.

  12. Bovine kappa-casein gene polymorphism and its association with milk production traits

    Directory of Open Access Journals (Sweden)

    Satyanarayana Rachagani

    2008-12-01

    Full Text Available Point mutations in exon IV of the bovine κ-casein (CSN3 gene determine two allelic variants, A and B. These variants were distinguished by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP analysis in the indigenous Sahiwal and Tharparkar cattle breeds. DNA samples (252 Sahiwal and 56 Tharparkar were analyzed for allelic variants of the CSN3 gene. Polymorphism was detected by digestion of PCR-amplified products with HindIII, HhaI and HaeIII restriction enzymes, followed by separation on 3% agarose gels, and resolved by ethidium bromide staining. Allele A of the κ-casein gene occurred at a higher frequency than allele B, in both Sahiwal and Tharparkar breeds. The genotypic frequencies of AA, AB, and BB in the Sahiwal and Tharparkar breeds were 0.758, 0.230 and 0.012, and 0.0.732, 0.250 and 0.018, respectively. The frequencies of alleles A and B in the Sahiwal and Tharparkar breeds were 0.873 and 0.127, and 0.857 and 0.143, respectively. Genotype BB of the kappa-casein gene had more influence on the monthly milk yield, 305-days milk yield, monthly solids-not-fat (SNF yield, and monthly protein yield, in the Sahiwal cattle.

  13. Casein peptization, functional properties, and sensory acceptance of processed cheese spreads made with different emulsifying salts.

    Science.gov (United States)

    Cunha, Clarissa R; Viotto, Walkiria H

    2010-01-01

    "Requeijão cremoso" is a traditional Brazilian processed cheese spread, showing ample acceptance on the national market. Emulsifying salts (ES) are an important factor influencing the characteristics of processed cheeses, but the literature presents conflicting results about their action on cheese functionality. Requeijão cremoso obtained from anhydrous ingredients allows the study of the influence of each type of ES on the cheese properties, since it can be treated as a model system where the variables are limited and well known. The objective of this study was to evaluate the effect of different types of ES (TSC-sodium citrate, SHMP-sodium hexametaphosphate, STPP-sodium tripolyphosphate, and TSPP-tetrasodium pyrophosphate) on the sensory and functional characteristics of requeijão cremoso-processed cheeses obtained from anhydrous ingredients. The physicochemical composition, degree of casein dissociation, fat particle size, melting index, color, texture profile, and sensory acceptance of the cheeses were determined. The functional behavior of processed cheeses was strongly influenced by the type of ES and its physicochemical properties including its ability to bind Ca, the casein dispersion during cooking, and the possible creation of cross-links with casein during cooling. The cheese made with SHMP was the one most differentiated from the others, presenting lower melting index, whiter color, and higher values for hardness, gumminess, and adhesiveness. The differences in texture had an impact on sensory acceptance: with the exception of the sample manufactured with sodium hexametaphosphate, all the samples presented good sensory acceptance.

  14. Genetic parameters for casein and urea content in the Italian Brown Swiss dairy cattle

    Directory of Open Access Journals (Sweden)

    O. Pedron

    2010-04-01

    Full Text Available A total of 137,753 test day records of 20,745 Italian Brown Swiss dairy cows from 26 provinces of Italy were used to estimate heritability for casein and urea content in milk and their genetic correlations with other production traits and milk somatic cell score. Milk component values were obtained by Fourier Transformed Infrared (IR Spectroscopy from milk samples collected during national routine recording and were analysed using test day repeatability animal models. Fixed effects included 1,001 levels of herd-test date, 15 classes of days in milk, and 13 classes of age at calving within parity. The variation among cows was large for most of the traits. The heritability value for casein content was 0.31, as for protein content, and genetic and phenotypic correlations between these two traits were large (0.99 and 0.97 respectively. Milk urea content had a heritability of 0.17 and a positive genetic relationship with fat (0.12, null with protein (0.03 and casein (0.002 content and a negative genetic correlation with milk yield (-0.17 suggesting that the genetic improvement for milk urea content would be possible, but genetic gain would be affected by other traits included as selection criteria in the economic index and by their relative economic emphasis.

  15. Influence of ultrasound on chemically induced gelation of micellar casein systems.

    Science.gov (United States)

    Chandrapala, Jayani; Zisu, Bogdan; Kentish, Sandra; Ashokkumar, Muthupandian

    2013-05-01

    Gelation is a significant operation in dairy processing. Protein gelation can be affected by several factors such as temperature, pH, or enzyme addition. Recently, the use of ultrasonication has been shown to have a significant impact on the formation of whey protein gels. In this work, the effect of ultrasonication on the gelation of casein systems was investigated. Gels were formed by the addition of 7.6 mm Tetra Sodium Pyro Phosphate (TSPP) to 5 wt% micellar casein (MC) solutions. Sonication at 20 KHz and 31 W for up to 30 min changed the surface hydrophobicity of the proteins, whereas surface charge was unaltered. Sonication before the addition of TSPP formed a firm gel with a fine protein network and low syneresis. Conversely, sonication after TSPP addition led to an inconsistent weak-gel-like structure with high syneresis. Gel strength in both cases increased significantly after short sonication times, while the viscoelastic properties were less affected. Overall, the results showed that ultrasonication can have a significant effect on the final gel properties of casein systems.

  16. Kinetics of N(ε)-(carboxymethyl)lysine formation in aqueous model systems of sugars and casein.

    Science.gov (United States)

    Nguyen, Ha T; van der Fels-Klerx, H J; van Boekel, Martinus A J S

    2016-02-01

    This study investigated the formation of N(ε)-carboxymethyllysine (CML) in two caseinate solutions containing: (1) glucose, (2) lactose, each heated at 120 °C and 130 °C. At both heating temperatures, CML concentration in lactose-caseinate solution was higher than in glucose-caseinate solution. In both solutions, more CML was formed at 130 °C than at 120 °C. Using multiresponse modelling, two degradation routes for the sugars were confirmed: (1) isomerisation of glucose or lactose and subsequent degradation via Lobry de Bruyn-Alberda van Ekenstein (LA) arrangement; (2) the Maillard reaction between the reducing sugar and lysine residues. Modelling results suggested that CML was not formed from oxidation of the reducing sugars, but from the Maillard reaction via the Amadori rearrangement product. Since CML appeared to be thermally unstable under the current study conditions, it may not be a perfect indicator for heat damage of processed foods. This is the first study in which CML formation was linked to available information on the Maillard reaction via multiresponse modelling.

  17. Incorporation of radiolabeled whey proteins into casein micelles by heat processing

    Energy Technology Data Exchange (ETDEWEB)

    Noh, B.; Richardson, T. (Univ. of California, Davis (USA))

    1989-07-01

    Skim milk was heated at .70, 95, and 140{degree}C to simulate the processes of pasteurization, forewarming, and UHT sterilization, and the specific interactions between {alpha}-lactalbumin or {beta}-lactoglobulin and the caseins studied using tracer amounts of added {sup 14}C-labeled whey protein. Radioactivities of the whey and of the washed casein pellets from renneted skim milk were measured and the extent of the interaction estimated. Upon heating skim milk at 70{degree}C for 45 s, less than 2% {beta}-lactoglobulin and less than .3% {alpha}-lactalbumin were incorporated into the curd. Heating at 95{degree}C for .5 to 20 min resulted in 58 to 85% of the {beta}-lactoglobulin and 8 to 55% of the {alpha}-lactalbumin becoming associated with the curd. Heating at 140{degree}C for 2 and 4 s caused 43 and 54% of the {beta}-lactoglobulin and 9 and 12% of the {alpha}-lactalbumin, respectively, to be bound to the curd fraction. The radiolabeling technique is very sensitive and useful for tracing low levels of interaction between whey proteins and casein in heated milk systems.

  18. Enhanced dispersibility and bioactivity of curcumin by encapsulation in casein nanocapsules.

    Science.gov (United States)

    Pan, Kang; Zhong, Qixin; Baek, Seung Joon

    2013-06-26

    In this work, a novel encapsulation method was studied by spray-drying a warm aqueous ethanol solution with codissolved sodium caseinate (NaCas) and lipophilic food components, using curcumin as a model compound. The encapsulation caused the loss of crystallinity of curcumin. After hydration of spray-dried powder and centrifugation, 137 μg/mL curcumin was dispersed in the transparent dispersion, which was 4 decades higher than its water solubility. Dynamic light scattering and atomic force microscopy results showed that curcumin-loaded casein nanoparticles were bigger than those of NaCas processed at encapsulation conditions but were smaller than those of the native NaCas. The increased nanoparticle dimension, together with fluorescence and FTIR spectroscopy results, suggested that curcumin was entrapped in the nanoparticle core through hydrophobic interactions. The curcumin encapsulated in casein nanoparticles had higher biological activity, as assessed by antioxidant and cell proliferation assays, than pristine curcumin, likely due to the improved dispersibility. This simple approach may be applied to encapsulate various lipophilic bioactive compounds.

  19. Calcium, vitamin D, casein and whey protein intakes and periodontitis among Danish adults

    DEFF Research Database (Denmark)

    Adegboye, Amanda Ra; Boucher, Barbara J; Kongstad, Johanne

    2016-01-01

    OBJECTIVE: To investigate whether intakes of Ca, vitamin D, casein and whey are associated with periodontitis and to investigate the possibility of interactions between them. DESIGN: Cross-sectional study. An Internet-based, 267-item FFQ was used to assess dietary intake. Intakes of casein (32.0 g....../d), whey proteins (9.6 g/d) and vitamin D (5.8 μg/d) were classified as within v. above the 50th percentile. Ca intake was classified as within v. below age-specific recommendations. Severe periodontitis was defined as having ≥2 inter-proximal sites with clinical attachment loss ≥6 mm (not on the same...... study of DANHES 2007-2008. RESULTS: Intakes of Ca within recommendations (OR=0.76; 95% CI 0.58, 0.99), whey ≥9.6 g/d (OR=0.75; 95% CI 0.58, 0.97) and casein ≥32 g/d (OR=0.75 95% CI 0.58, 0.97) were associated with lower likelihood of severe periodontitis after adjustment for age, gender, education...

  20. Stimulation of muscle protein synthesis by whey and caseinate ingestion after resistance exercise in elderly individuals

    DEFF Research Database (Denmark)

    Dideriksen, Kasper; Reitelseder, Søren; Petersen, S.G.

    2011-01-01

    -(13) C]leucine using labeled proteins during a 6-h recovery period. No differences were observed in muscle myofibrillar and collagen FSR with Whey (0.09 ± 0.01%/h) compared with CasPost (0.09 ± 0.003%/h), and it did not differ between CasPre (0.10 ± 0.01%/h) and CasPost. MPS does not differ with whey......Sarcopenia is a well-known phenomenon in elderly individuals and resistance exercise together with sufficient amino acid (AA) availability has proved to be a counteractive implement. However, the source of AA and supplement timing require further investigation. The objective was to compare muscle...... protein synthesis (MPS) to intakes of whey and caseinate after heavy resistance exercise in healthy elderly individuals, and, furthermore, to compare the timing effect of caseinate intake. Twenty-four elderly men and women (mean ± SEM; 68 ± 1 years) were randomized to one of four groups: caseinate intake...

  1. Biosurfactant Production by Cultivation of Bacillus atrophaeus ATCC 9372 in Semidefined Glucose/Casein-Based Media

    Science.gov (United States)

    Das Neves, Luiz Carlos Martins; de Oliveira, Kátia Silva; Kobayashi, Márcio Junji; Vessoni Penna, Thereza Christina; Converti, Attilio

    Biosurfactants are proteins with detergent, emulsifier, and antimicrobial actions that have potential application in environmental applications such as the treatment of organic pollutants and oil recovery. Bacillus atrophaeus strains are nonpathogenic and are suitable source of biosurfactants, among which is surfactin. The aim of this work is to establish a culture medium composition able to stimulate biosurfactants production by B. atrophaeus ATCC 9372. Batch cultivations were carried out in a rotary shaker at 150 rpm and 35°C for 24 h on glucose- and/or casein-based semidefined culture media also containing sodium chloride, dibasic sodium phosphate, and soy flour. The addition of 14.0 g/L glucose in a culture medium containing 10.0 g/L of casein resulted in 17 times higher biosurfactant production (B max=635.0 mg/L). Besides, the simultaneous presence of digested casein (10.0 g/L), digested soy flour (3.0 g/L), and glucose (18.0 g/L) in the medium was responsible for a diauxic effect during cell growth. Once the diauxie started, the average biosurfactants concentration was 16.8% less than that observed before this phenomenon. The capability of B. atrophaeus strain to adapt its own metabolism to use several nutrients as energy sources and to preserve high levels of biosurfactants in the medium during the stationary phase is a promising feature for its possible application in biological treatments.

  2. Gluten- and casein-free dietary intervention for autism spectrum conditions.

    Directory of Open Access Journals (Sweden)

    Paul eWhiteley

    2013-01-01

    Full Text Available Dietary intervention as a tool for maintaining and improving physical health and wellbeing is a widely researched and discussed topic. Speculation that diet may similarly affect mental health and wellbeing particularly in cases of psychiatric and behavioural symptomatology opens up various avenues for potentially improving quality of life. We examine evidence suggestive that a gluten-free, casein-free or combined gluten- and casein-free diet can ameliorate core and peripheral symptoms and improve developmental outcome in some cases of autism spectrum conditions. Although not wholly affirmative, the majority of published studies indicate statistically significant positive changes to symptom presentation following dietary intervention. In particular, changes to areas of communication, attention and hyperactivity are detailed, despite the presence of various methodological shortcomings. Specific characteristics of best- and non-responders to intervention have not been fully elucidated; neither has the precise mode of action for any universal effect outside of known individual cases of food-related co-morbidity. With the publication of controlled medium- and long-term group studies of a gluten- and casein-free diet alongside more consolidated biological findings potentially linked to intervention, the appearance of a possible diet-related autism phenotype seems to be emerging supportive of a positive dietary effect in some cases. Further debate on whether such dietary intervention should form part of best practice guidelines for autism spectrum conditions and onward representative of an autism dietary-sensitive enteropathy is warranted.

  3. Optimization of caseinate-coated simvastatin-zein nanoparticles: improved bioavailability and modified release characteristics

    Directory of Open Access Journals (Sweden)

    Ahmed OA

    2015-01-01

    Full Text Available Osama AA Ahmed,1,2 Khaled M Hosny,1,3 Majid M Al-Sawahli,1,4 Usama A Fahmy11Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia; 2Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Minia University, Minia, Egypt; 3Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Beni Suef University, Beni Suef, Egypt; 4Holding Company for Biological Products & Vaccines (VACSERA, Cairo, EgyptAbstract: The current study focuses on utilization of the natural biocompatible polymer zein to formulate simvastatin (SMV nanoparticles coated with caseinate, to improve solubility and hence bioavailability, and in addition, to modify SMV-release characteristics. This formulation can be utilized for oral or possible depot parenteral applications. Fifteen formulations were prepared by liquid–liquid phase separation method, according to the Box–Behnken design, to optimize formulation variables. Sodium caseinate was used as an electrosteric stabilizer. The factors studied were: percentage of SMV in the SMV-zein mixture (X1, ethanol concentration (X2, and caseinate concentration (X3. The selected dependent variables were mean particle size (Y1, SMV encapsulation efficiency (Y2, and cumulative percentage of drug permeated after 1 hour (Y3. The diffusion of SMV from the prepared nanoparticles specified by the design was carried out using an automated Franz diffusion cell apparatus. The optimized SMV-zein formula was investigated for in vivo pharmacokinetic parameters compared with an oral SMV suspension. The optimized nanosized SMV-zein formula showed a 131 nm mean particle size and 89% encapsulation efficiency. In vitro permeation studies displayed delayed permeation characteristics, with about 42% and 85% of SMV cumulative amount released after 12 and 48 hours, respectively. Bioavailability estimation in rats revealed an augmentation in SMV bioavailability

  4. Proving the adulteration of ewe and goat cheeses with cow milk using the reference method of isoelectric focusing of γ-casein

    OpenAIRE

    Nataša Mikulec; Dijana Plavljanić; Jasminka Špoljarić; Biljana Radeljević; Jasmina Havranek; Neven Antunac

    2013-01-01

    The aim of this study was to introduce a reference method for the detection of cow milk in ewe and goat cheeses (EC 273/08) in order to protect manufacturers and consumers from adulterations and imitations, and to ensure alignment with the demands of domestic and EU markets. The method includes isolation of casein from cheese, isoelectric focusing of γ2- and γ3-casein originating from the hydrolysis of β-casein by plasmin, the detection and quantitative determination of γ-casein in cow, ewe a...

  5. 酪蛋白胶束结构研究方法综述%A review on the studying means of casein micelle structure

    Institute of Scientific and Technical Information of China (English)

    史莹; 杨敏; 梁琪; 乔海军; 张卫兵

    2012-01-01

    Caseins,the main components of milk protein, represent about 80% of the total protein in the milk.Owing to the importance of casein and casein micelles for the functional behavior of dairy products, and widely application of caseins, the study of casein is always drawing more attention.Especially, the exact structure of casein micelles is still under debate.Many scholars have proposed various theoretic models for casein micelle structure. This paper reviewed kinds means of casein micelles structure,dissociation and aggregation in order to provide a reference for studying casein in the future.%酪蛋白是乳中蛋白质的主要成分,约占其80%。由于酪蛋白胶束对乳制品的功能特性起重要作用,因此其研究一直备受关注,但酪蛋白胶束的内部结构至今没有确切的定义,而是许多学者提出了各种理论模型。文章综述了酪蛋白胶束结构、解离与聚集的多种研究方法,为以后学者研究酪蛋白提供借鉴。

  6. Studies on the photophysical properties of 1,8-naphthalimide derivative and aggregation induced emission recognition for casein

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yang, E-mail: 66160692@qq.com [Department of Chemistry and Chemical Engineering, Xi' an University of Arts and Science, No. 168, Taibai South Road, Xi' an, Shaanxi 710065 (China); Liang, Xuhua; Fan, Jun [School of Chemical Engineering, Northwest University, No. 229, Taibai North Road, Xi' an, Shaanxi 710069 (China); Han, Quan, E-mail: xahanq@hotmail.com [Department of Chemistry and Chemical Engineering, Xi' an University of Arts and Science, No. 168, Taibai South Road, Xi' an, Shaanxi 710065 (China)

    2013-09-15

    A novel water-soluble 1,8-naphthalimide derivative 1, bearing two acetic carboxylic groups, exhibited fluorescent turn-on recognition for casein micelle based on the aggregation induced emission (AIE) character. The photophysical properties of 1 consisting of donor and acceptor units were investigated by the solvation effect. Changing from polar to non-polar solvent increased the solvent interaction; both the excitation and emission spectra were shifted to shorter wavelength and intensity decreased through taking advantage of twisted intramolecular charge transfer (TICT) and self-association fluorescence emission. Moreover, the red-shift and quenching in protic solvent were caused by the excited-state hydrogen bond strengthening effect. The density functional theory (DFT) and time dependent density functional theory (TDDFT) were used to obtain the most stable structure, electronic excitation energy, dipole moments and charge distribution. The AIE mechanism of 1 with casein micelle was due to 1 docked in the hydrophobic cavity between sub-micelles and bound with amino acid residues, resulting in the aggregation of 1 on the casein micelle surface and emission enhancement, based on which, a novel casein assay method was developed. The proposed method exhibited a good linear range from 0.1 to 10.5 μg mL{sup −1}, with the detection limit of 3.0 ng mL{sup −1}. Satisfactory reproducibility, reversibility and a short response time were realized. This method was applied for the determination of casein in milk powder samples, avoiding the interferences from other components and illegal additives in milk. -- Highlights: • A water-soluble 1,8-naphthalimide-based fluorescent probe 1 was synthesized. • Photophysical characterization of 1 was studied. • Aggregation induced emission enhancement of 1 with casein was investigated. • A novel casein quantification method was developed.

  7. Short communication: retinoic acid plus prolactin to synergistically increase specific casein gene expression in MAC-T cells.

    Science.gov (United States)

    Lee, H Y; Heo, Y T; Lee, S E; Hwang, K C; Lee, H G; Choi, S H; Kim, N H

    2013-06-01

    Mammary alveolar (MAC-T) cells, an established bovine mammary epithelial cell line, are frequently used to investigate differentiation. A lactogenic phenotype in these cells is induced by treatment with a combination of hydrocortisone, insulin, and prolactin (PRL). The effect of the vitamin A derivative retinoic acid (RA), which induces differentiation in many cells, has not been studied in MAC-T cells. The objective of this study was to evaluate the differentiation potential of RA (1 μM) in MAC-T cells and to examine the effect of combined treatment with RA (1 μM) and PRL (5 μg/mL). Although RA treatment alone inhibited MAC-T cell proliferation, co-treatment of RA with PRL increased cell growth compared with the control group (treated with 1 μg/mL hydrocortisone and 5 μg/mL insulin). The ratio of Bcl to Bax mRNA was decreased in the RA treatment compared with RA+PRL or control. Retinoic acid-induced differentiation of MAC-T cells was associated with an increase in the mRNA expression of αS1-casein (3.9-fold), αS2-casein (4.5-fold), and β-casein (4.4-fold) compared with the control group. Expression of αS1-casein, αS2-casein, and β-casein was increased 12.9-fold, 11.9-fold, and 19.3-fold, respectively, following treatment with RA and PRL combined compared with the control group. These results demonstrate that RA induces differentiation of MAC-T cells and acts synergistically with PRL to increase specific casein gene expression.

  8. Separation and characterization of mares' milk alpha(s1)-, beta-, kappa-caseins, gamma-casein-like, and proteose peptone component 5-like peptides.

    Science.gov (United States)

    Egito, A S; Miclo, L; López, C; Adam, A; Girardet, J M; Gaillard, J L

    2002-04-01

    The equine alpha(s1)- and beta-caseins (CN) were purified by chromatography on DEAE-cellulose and by reversed-phase HPLC. The alpha(s1)-, beta-, and kappa-CN were characterized either by monodimensional urea-PAGE or sodium dodecylsulfate (SDS)-PAGE or by bidimensional electrophoresis. Kappa-casein was characterized after electrophoresis by glycoprotein-specific staining. To identify alpha(s1)-CN without ambiguity, internal sequences were determined after trypsin or chymosin digestion of purified alpha(s1)-CN. These sequences, that could be estimated to correspond to 62% of the full protein, presented strong identities with regions of alpha(s1)-CN primary structures of other species. In particular, 51, 48, 43, and 40% identities were obtained with corresponding regions of sow, dromedary, cow, and human alpha(s1)-CN, respectively. On the other hand, trace amounts of equine gamma-CN-like and proteose peptone component 5-like peptides were found in the whole CN. They were identified by microsequencing and corresponded to beta-CN peptides generated by plasmin action on the whole CN. The equine alpha(s1), beta-, and kappa-CN were separated by bidimensional electrophoresis in numerous isoelectric variants with apparent isoelectric points distributed between pH 4.4 to 6.3, 4.4 to 5.9, and 3.5 to 5.5, respectively. The beta- and kappa-CN displayed a more acidic character in the mare than in the cow.

  9. Marked effect of beta-lactoglobulin polymorphism on the ratio of casein to total protein in milk.

    Science.gov (United States)

    Lundén, A; Nilsson, M; Janson, L

    1997-11-01

    The relationship between genetic variants for milk protein and the composition of milk was analyzed on 4475 repeated milk samples from individual cows; 371 dairy cows of the Swedish Red and White breed and 204 cows of the Swedish Holstein breed were used. The registrations included percentages of casein, protein, fat, and lactose in combination with milk yield and SCC. The genotype of individual cows for alpha(s1)-CN, beta-CN, kappa-CN, and beta-LG was determined by alkaline and acidic PAGE. A mixed animal model was used for the analysis; beta-LG and aggregate casein genotypes were included simultaneously as separate fixed effects in the statistical model. The results suggest a positive additive effect of the beta-LG B allele on casein content and on the ratio of casein to total protein. For the latter trait, the beta-LG genotype accounted for a relatively large part of the phenotypic variance, corresponding to a reduction in residual variance of 11% when included in the model. The corresponding value for casein content was 0.5%. The lack of unfavorable associations between milk protein variants and the traits included in this study makes the beta-LG gene an obvious candidate when the breeding objective is improved conversion of milk protein into cheese.

  10. Co-autodisplay of Z-domains and bovine caseins on the outer membrane of E. coli.

    Science.gov (United States)

    Yoo, Gu; Saenger, Thorsten; Bong, Ji-Hong; Jose, Joachim; Kang, Min-Jung; Pyun, Jae-Chul

    2015-12-01

    In this work, two proteins, Z-domains and bovine casein, were auto-displayed on the outer membrane of the same Escherichia coli cells by co-transformation of two different auto-display vectors. On the basis of SDS-PAGE densitometry, Z-domains and bovine casein were expressed at 3.12 × 10⁵ and 1.55 × 10⁵ proteins/E. coli cell, respectively. The co-auto-displayed Z-domains had antibody-binding activity and the bovine casein had adhesive properties. E. coli with co-auto-displayed proteins were analyzed by fluorescence assisted cell sorting (FACS). E. coli with co-auto-displayed Z-domains and bovine casein aggregated due to hydrophobic interaction. For application to immunoassays, the Z-domain activity was estimated after (1) immobilizing the E. coli and (2) forming an OM layer. E. coli with co-auto-displayed two proteins that were immobilized on a polystyrene microplate had the same antibody-binding activity as did E. coli with auto-displayed Z-domains only. The OM layer from the co-transformed E. coli had Z-domains and bovine casein expressed at a 1:2 ratio from antibody-binding activity measurements.

  11. Comparative analysis on the structural features of the 5' flanking region of κ-casein genes from six different species

    Directory of Open Access Journals (Sweden)

    Whitelaw C Bruce A

    2002-01-01

    Full Text Available Abstract κ-casein plays an essential role in the formation, stabilisation and aggregation of milk micelles. Control of κ-casein expression reflects this essential role, although an understanding of the mechanisms involved lags behind that of the other milk protein genes. We determined the 5'-flanking sequences for the murine, rabbit and human κ-casein genes and compared them to the published ruminant sequences. The most conserved region was not the proximal promoter region but an approximately 400 bp long region centred 800 bp upstream of the TATA box. This region contained two highly conserved MGF/STAT5 sites with common spacing relative to each other. In this region, six conserved short stretches of similarity were also found which did not correspond to known transcription factor consensus sites. On the contrary to ruminant and human 5' regulatory sequences, the rabbit and murine 5'-flanking regions did not harbour any kind of repetitive elements. We generated a phylogenetic tree of the six species based on multiple alignment of the κ-casein sequences. This study identified conserved candidate transcriptional regulatory elements within the κ-casein gene promoter.

  12. Kappa-Casein Genotypic Frequencies in Holstein-Friesian Dairy Cattle in West Java Province

    Directory of Open Access Journals (Sweden)

    A. Anggraeni

    2010-08-01

    Full Text Available Kappa casein (ĸ-cn gene as one of the four casein genes commonly has two variant alleles. B allele is positively correlated with milk proteins, so potentially be used as MAS to improve milk protein content. This study aimed to identify genetic variation of the ĸ-casein gene in Holstein-Friesian (HF from several dairy regions in West Java. Blood samples were taken through jugular vein of lactating heifers and cows, from intensive managements under the Local Government Dairy Breeding Station - Cikole (BBPT Cikole-SP (82 hds, Embryo Transfer Station (BET (50 hds, and Eco Farm of Animal Science Faculty of Bogor Agricultural University (EcoFarm (20 hds; as well as from semi-intensive managements of small dairy farmers under the supervision of the North Lembang Cooperative Unit (KPSBU Lembang in two villages of Cilumber (98 hds and Pasar Kemis (92 hds. Blood samples were also taken via cocsigalis vein of AI (active and non active HF bulls at the two National AI Stations in Lembang (25 hds and Singosari (32 hds. Identification of genetic variation was by applying PCR-RFLP method. Three genotypes were identified, namely AA, AB, and BB, resulting two alleles of A and B. Results entirely showed that the frequencies of the BB HF female were very low, with the range of 0%-6% (vs AA genotype= 10%-54% and AB genotype= 46%-85%, despite of the relatively high frequency of the B allele over the A allele (23%-48% vs. 52%-77%. The low frequency of the observed BB females might be due to the limited AI active BB bulls used for services by the two national AI stations (0%-4%.

  13. Casein haplotypes and their association with milk production traits in Norwegian Red cattle.

    Science.gov (United States)

    Nilsen, Heidi; Olsen, Hanne Gro; Hayes, Ben; Sehested, Erling; Svendsen, Morten; Nome, Torfinn; Meuwissen, Theo; Lien, Sigbjørn

    2009-02-20

    A high resolution SNP map was constructed for the bovine casein region to identify haplotype structures and study associations with milk traits in Norwegian Red cattle. Our analyses suggest separation of the casein cluster into two haplotype blocks, one consisting of the CSN1S1, CSN2 and CSN1S2 genes and another one consisting of the CSN3 gene. Highly significant associations with both protein and milk yield were found for both single SNPs and haplotypes within the CSN1S1-CSN2-CSN1S2 haplotype block. In contrast, no significant association was found for single SNPs or haplotypes within the CSN3 block. Our results point towards CSN2 and CSN1S2 as the most likely loci harbouring the underlying causative DNA variation. In our study, the most significant results were found for the SNP CSN2_67 with the C allele consistently associated with both higher protein and milk yields. CSN2_67 calls a C to an A substitution at codon 67 in beta-casein gene resulting in histidine replacing proline in the amino acid sequence. This polymorphism determines the protein variants A1/B (CSN2_67 A allele) versus A2/A3 (CSN2_67 C allele). Other studies have suggested that a high consumption of A1/B milk may affect human health by increasing the risk of diabetes and heart diseases. Altogether these results argue for an increase in the frequency of the CSN2_67 C allele or haplotypes containing this allele in the Norwegian Red cattle population by selective breeding.

  14. Application of Asian pumpkin (Cucurbita ficifolia) serine proteinase for production of biologically active peptides from casein.

    Science.gov (United States)

    Dąbrowska, Anna; Szołtysik, Marek; Babij, Konrad; Pokora, Marta; Zambrowicz, Aleksandra; Chrzanowska, Józefa

    2013-01-01

    The main objective of this study was to determine potential application of a serine proteinase derived from Asian pumpkin for obtaining biologically active peptides from casein. The course of casein hydrolysis by three doses of the enzyme (50, 150, 300 U/mg of protein) was monitored for 24 hours by the determinations of: hydrolysis degree DH (%), free amino group content (μmole Gly/g), RP HPLC peptide profiles and by polyacrylamide gel electrophoresis. In all hydrolyzates analyzed antioxidant activities were determined using three tests: the ability to reduce iron ions in FRAP test, the ability to scavenge free radicals in DPPH test, and Fe(2+) chelating activity. The antimicrobial activity of obtained peptide fractions was determined as the ability to inhibit the growth of Escherichia coli, Bacillus cereus and Pseudomonas fluorescens in a diffusion plate test. The deepest degradation, expressed as the DH [%] and the free amino group content (67% and 7528 µmole Gly/mg, respectively), was noted in samples hydrolyzed with 300 U/ml of enzyme for 24 hours, while in other samples the determined values were about three and two times lower. The results were in agreement with the peptide profiles obtained by RP HPLC. The highest antioxidative activities determined in all tests were seen for the casein hydrolysate obtained with 300 U/mg protein of serine proteinase after 24 h of reaction (2.15 µM Trolox/mg, 96.15 µg Fe(3+)/mg, 814.97 µg Fe(2+)/mg). Antimicrobial activity was presented in three preparations. In other samples no antimicrobial activity was detected.

  15. Structural Basis for the Potent and Selective Inhibition of Casein Kinase 1 Epsilon

    Energy Technology Data Exchange (ETDEWEB)

    Long, Alexander M. [Amgen Inc., Cambridge, MA (United States); Zhao, Huilin [Amgen Inc., Cambridge, MA (United States); Huang, Xin [Amgen Inc., Cambridge, MA (United States)

    2012-10-29

    Casein kinase 1 epsilon (CK1ε) and its closest homologue CK1δ are key regulators of diverse cellular processes. We report two crystal structures of PF4800567, a potent and selective inhibitor of CK1ε, bound to the kinase domains of human CK1ε and CK1δ as well as one apo CK1ε crystal structure. These structures provide a molecular basis for the strong and specific inhibitor interactions with CK1ε and suggest clues for further development of CK1δ inhibitors.

  16. The effect of sucrose on unfrozen water and syneresis of acidified sodium caseinate-xanthan gels.

    Science.gov (United States)

    Braga, A L M; Cunha, R L

    2005-07-01

    The influence of the ingredients of acidified Na caseinate-xanthan-sucrose gels on thermophysical properties and syneresis of the gels was studied. Sucrose concentration affected all of the gel equilibrium properties and the rate of syneresis. The positive effect of sucrose on syneresis and unfrozen water (UFW) values was attributed to different effects. The amount of UFW was governed mainly by the colligative properties of sucrose whereas the equilibrium syneresis behaviour was associated with the changes in network dynamics caused by the kosmotropic properties of sucrose. The latter could enhance xanthan-sucrose association or favour xanthan-protein interactions.

  17. Differential effects of casein versus whey on fasting plasma levels of insulin, IGF-1 and IGF-1/IGFBP-3

    DEFF Research Database (Denmark)

    Hoppe, Camilla; Mølgaard, Christian; Dalum, Cathrine

    2009-01-01

    to the identification of which components in milk that stimulate growth, we have performed an intervention study with 57 eight-year-old boys in which we examined the effects of the two major milk protein fractions, whey and casein, and milk minerals (Ca and P) in a 2x2 factorial design on IGFs and glucose......–insulin metabolism. The amounts of whey and casein were identical to the content in 1.5 l skim milk. The amounts of Ca and P were similar to 1.5 l skim milk in the high-mineral drinks, whereas the amounts of Ca and P were reduced in the low-mineral drinks. Results: There were no interactions between milk mineral...... groups (high, low) and milk protein groups (whey, casein). Serum IGF-1 increased by 15% (P...

  18. Quantification of αS1-casein in breast milk using a targeted mass spectrometry-based approach.

    Science.gov (United States)

    Altendorfer, Irina; König, Simone; Braukmann, Achim; Saenger, Thorsten; Bleck, Ellen; Vordenbäumen, Stefan; Kubiak, Anna; Schneider, Matthias; Jose, Joachim

    2015-01-25

    The caseins comprise a milk protein fraction of high nutritional value and, as more recently discovered, of immunologic relevance. In particular, αS1-casein (CSN1S1) is of interest being a potential autoantigen. So far, the concentration of caseins in human milk was primarily determined by indirect methods. The aim of this study was to directly measure the CSN1S1 content in breast milk using mass spectrometry (MS). The quantification was based on tryptic CSN1S1 peptides with the best response in liquid chromatography (LC)-MS/MS analysis. Targeted experiments allowed both specific and sensitive detection at the low fmol level. For this pilot study, twenty breast milk samples of the first week post-partum were analyzed and contained between 3 and 540μg/ml CSN1S1. Limitations of CSN1S1 quantification are discussed.

  19. Chaperone-like activity of β-casein and its effect on residual in vitro activity of horseradish peroxidase

    DEFF Research Database (Denmark)

    Sulewska, Anna Maria; Olsen, Karsten; Sørensen, Jens Christian

    2014-01-01

    , as similar experiment with bovine serum albumin resulted in residual activity of horseradish peroxidase that was significantly lower than without any addition. The effect of β-casein on HRP disappears when pH is below the isoelectric point of β-casein. It was also proven by light scattering studies that β...

  20. RNA-sequencing data analysis of uterus in ovariectomized rats fed with soy protein isolate,17B-estradiol and casein

    Science.gov (United States)

    This data file describes the bioinformatics analysis of uterine RNA-seq data comparing genome wide effects of feeding soy protein isolate compared to casein to ovariectomized female rats age 64 days relative to treatment of casein fed rats with 5 ug/kg/d estradiol and relative to rats treated with e...

  1. Cross-linking of bovine and caprine caseins by microbial transglutaminase and their use as microencapsulating agents for n-3 fatty acids

    Science.gov (United States)

    Bovine and caprine caseins were cross-linked with microbial transglutaminase (mTG). The mTG-cross-linked bovine or caprine casein dispersion, mixed with 14.5% maltodextrin (DE = 40), was used to prepare emulsions with 10.5% algae oil. Oxidative stability of emulsions was evaluated by peroxide valu...

  2. Do different casein concentrations increase the adverse effect of rutin on the biology of Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae)?

    Science.gov (United States)

    Salvador, Mariana C; Boiça, Arlindo L; de Oliveira, Maria C N; da Graça, José P; da Silva, Débora M; Hoffmann-Campo, Clara B

    2010-01-01

    The flavonoid rutin is recognized as playing an important role in the protection of plants against lepidopterans. Bioassays with this compound are generally carried out using artificial diets. Proteins of high energy value, such as casein, are important ingredients of insect artificial diets as a source of essential amino acids. However, such proteins can generally increase the allelochemical activity. Our objective was to evaluate the effects of rutin on larvae of the velvetbean caterpillar Anticarsia gemmatalis Hübner by incorporating this allelochemical into diets with different concentrations of casein. Three casein concentrations (0, 7 g, or 14 g) combined with none, 0.65%, or 1.30% of rutin were added to the rearing diet and offered to the larvae from hatching to pupation. Rutin negatively affected larval development, the amount of food consumed, and pupal weight of A. gemmatalis. These negative effects were clearly seen in insects fed on diets with 7 g of casein to which any concentration of rutin was added. The effects of rutin when added to the diets without casein were stronger than in diets containing a suitable amount of casein (14 g). The greater negative effects of rutin in diets containing suboptimal concentrations of casein indicate that casein can increase the effects of rutin only when the diets are nutritionally unsuitable for insect development.

  3. Modification of Casein and its Application in Leather Finishing%酪素的改性方法及其在皮革涂饰中的应用

    Institute of Scientific and Technical Information of China (English)

    唐瑶; 付柯; 赵丹; 张哲

    2015-01-01

    简述了酪素的性质,综述了酪素的改性方法及在皮革涂饰中的应用。%The properties of casein were briefly introduced. Modification methods of casein and its applica-tion in synthesizing leather finishing agents were reviewed.

  4. Effects of soy vs. casein protein on body weight and glycemic control in female monkeys and their offspring.

    Science.gov (United States)

    Wagner, Janice D; Jorgensen, Matthew J; Cline, J Mark; Lees, Cynthia J; Franke, Adrian A; Zhang, Li; Ayers, Melissa R; Schultz, Carrie; Kaplan, Jay R

    2009-09-01

    Nutritional interventions are important for reducing obesity and related conditions. Soy is a good source of protein and also contains isoflavones that may affect plasma lipids, body weight, and insulin action. Described here are data from a monkey breeding colony in which monkeys were initially fed a standard chow diet that is low fat with protein derived from soy. Monkeys were then randomized to a defined diet with a fat content similar to the typical American diet (TAD) containing either protein derived from soy (TAD soy) or casein-lactalbumin (TAD casein). The colony was followed for over two years to assess body weight, and carbohydrate and lipid measures in adult females (n=19) and their offspring (n=25). Serum isoflavone concentrations were higher with TAD soy than TAD casein, but not as high as when monkey chow was fed. Offspring consuming TAD soy had higher serum isoflavone concentrations than adults consuming TAD soy. Female monkeys consuming TAD soy had better glycemic control, as determined by fructosamine concentrations, but no differences in lipids or body weight compared with those consuming diets with TAD casein. Offspring born to dams consuming TAD soy had similar body weights at birth but over a two-year period weighed significantly less, had significantly lower triglyceride concentrations, and like adult females, had significantly lower fructosamine concentrations compared to TAD casein. Glucose tolerance tests in adult females were not significantly different with diet, but offspring eating TAD soy had increased glucose disappearance with overall lower glucose and insulin responses to the glucose challenge compared with TAD casein. Potential reasons for the additional benefits of TAD soy observed in offspring but not in adults may be related to higher serum isoflavone concentrations in offspring, presence of the diet differences throughout more of their lifespan (including gestation), or different tissue susceptibilities in younger animals.

  5. Immediate and residual effects of heat stress and restricted intake on milk protein and casein composition and energy metabolism.

    Science.gov (United States)

    Cowley, F C; Barber, D G; Houlihan, A V; Poppi, D P

    2015-04-01

    The effects of heat stress on dairy production can be separated into 2 distinct causes: those effects that are mediated by the reduced voluntary feed intake associated with heat stress, and the direct physiological and metabolic effects of heat stress. To distinguish between these, and identify their effect on milk protein and casein concentration, mid-lactation Holstein-Friesian cows (n = 24) were housed in temperature-controlled chambers and either subjected to heat stress [HS; temperature-humidity index (THI) ~78] or kept in a THIheat-stressed cows (TN-R) for 7 d. A control group of cows was kept in a THIheat stress. Heat stress reduced the milk protein concentration, casein number, and casein concentration and increased the urea concentration in milk beyond the effects of restriction of intake. Under HS, the proportion in total casein of αS1-casein increased and the proportion of αS2-casein decreased. Because no effect of HS on milk fat or lactose concentration was found, these effects appeared to be the result of specific downregulation of mammary protein synthesis, and not a general reduction in mammary activity. No residual effects were found of HS or TN-R on milk production or composition after THIHeat-stressed cows had elevated blood concentrations of urea and Ca, compared with TN-R and TN-AL. Cows in TN-R had higher serum nonesterified fatty acid concentrations than cows in HS. It was proposed that HS and TN-R cows may mobilize different tissues as endogenous sources of energy.

  6. Characterization of the alpha and beta subunits of casein kinase 2 by far-UV CD spectroscopy

    DEFF Research Database (Denmark)

    Issinger, O G; Brockel, C; Boldyreff, B;

    1992-01-01

    Although Chou-Fasman calculations of the secondary structure of recombinant casein kinase 2 subunits alpha and beta suggest they have a similar overall conformation, circular dichroism (CD) studies show that substantial differences in the conformation of the two subunits exist. In addition......, no changes in the far-UV CD spectrum of the alpha subunit are observed in the presence of casein or the synthetic decapeptide substrate RRRDDDSDDD. Furthermore, the alpha-helical structure of the alpha subunit (but not the beta subunit) can be increased in the presence of stoichiometric amounts of heparin...

  7. Rennet-induced gelation of concentrated milk in the presence of sodium caseinate: differences between milk concentration using ultrafiltration and osmotic stressing.

    Science.gov (United States)

    Krishnankutty Nair, P; Corredig, M

    2015-01-01

    Concentrating milk is a common unit operation in the dairy industry. With the reduction of water, the particles interact more frequently with each other and the functionality of the casein micelles may depend on the interactions occurring during concentration. The objective of this research was to investigate the effect of concentration on the renneting properties of the casein micelles by comparing 2 concentration methods: ultrafiltration and osmotic stressing. Both methods selectively concentrate the protein fraction of milk, while the composition of the soluble phase is unaltered. To evaluate possible differences in the rearrangements of the casein micelles during concentration, renneting properties were evaluated with or without the addition of soluble caseins, added either before or after concentration. The results indicate that casein micelles undergo rearrangements during concentration and that shear during membrane filtration may play a role in affecting the final properties of the milk.

  8. Dystroglycan loss disrupts polarity and beta-casein induction inmammary epithelial cells by perturbing laminin anchoring

    Energy Technology Data Exchange (ETDEWEB)

    Weir, M. Lynn; Oppizzi, Maria Luisa; Henry, Michael D.; Onishi,Akiko; Campbell, Kevin P.; Bissell, Mina J.; Muschler, John L.

    2006-02-17

    Precise contact between epithelial cells and their underlying basement membrane is critical to the maintenance of tissue architecture and function. To understand the role that the laminin receptor dystroglycan (DG) plays in these processes, we assayed cell responses to laminin-111 following conditional ablation of DG expression in cultured mammary epithelial cells (MECs). Strikingly, DG loss disrupted laminin-111-induced polarity and {beta}-casein production, and abolished laminin assembly at the step of laminin binding to the cell surface. DG re-expression restored these deficiencies. Investigations of mechanism revealed that DG cytoplasmic sequences were not necessary for laminin assembly and signaling, and only when the entire mucin domain of extracellular DG was deleted did laminin assembly not occur. These results demonstrate that DG is essential as a laminin-111 co-receptor in MECs that functions by mediating laminin anchoring to the cell surface, a process that allows laminin polymerization, tissue polarity, and {beta}-casein induction. The observed loss of laminin-111 assembly and signaling in DG-/-MECs provides insights into the signaling changes occurring in breast carcinomas and other cancers, where DG's laminin-binding function is frequently defective.

  9. Novel hierarchical microparticles super-assembled from nanoparticles with the induction of casein micelles

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Xiaopeng, E-mail: xpxiong@xmu.edu.cn; Duan, Jiangjiang; Wang, Yong; Yu, Zhaoju [Xiamen University, Department of Materials Science and Engineering, College of Materials (China)

    2013-08-15

    We have demonstrated a solution-based synthesis of novel waxberry-like hierarchical ZnO microparticles in the presence casein micelles under mild conditions. The microstructures of the sub-micrometer-sized hierarchical microparticles were characterized, and the synthesis conditions were optimized. The formation mechanism of the hierarchical microparticle was analyzed through control experiments. The hierarchical ZnO microparticles are found to be super-assemblies of 30-70 nm ZnO nanoparticles, which are thought to be based on casein micelle induction followed by Ostwald ripening. In the same manner, copper-based hierarchical microparticles with a similar morphology have also been successfully synthesized. By controlling the synthetic time or temperature, solid or hollow microparticles can be fabricated. The narrowly distributed ZnO microparticles have a high specific surface area, exhibiting great potential application in fields such as photocatalytic and energy conversion. Our findings may meanwhile open a new bottom-up strategy in order to construct structurally sophisticated nanomaterials.

  10. Encapsulation of antioxidant peptide enriched casein hydrolysate using maltodextrin-gum arabic blend.

    Science.gov (United States)

    Rao, Priyanka Singh; Bajaj, Rajesh Kumar; Mann, Bimlesh; Arora, Sumit; Tomar, S K

    2016-10-01

    Antioxidant peptide enriched casein hydrolysate (AO-CH) are receiving increasing attention due to their potential as functional ingredient. Encapsulation of AO-CH using maltodextrin-gum arabic (MD/GA) as wall material could represent an attractive approach to overcome the problems related to their direct application. Encapsulation parameter were optimized using different ratio of core to coat and proportion of coating material (10:0, 8:2, 6:4) under varying pH (2-8) for encapsulation efficiency (EE).The preparation P3 resulted in maximum EE (87%) using core to coat ratio 1:20, at pH 6.0 with 8:2 MD/GA ratio. The encapsulated preparation showed reduced bitterness (p < 0.05) compared to the casein hydrolysate together with maximum retention of antioxidant activity (93%). Further, the narrow range of particle size, indicates their better stability and represents a promising food additive for incorporation in food.

  11. Casein gene expression in mouse mammary epithelial cell lines: Dependence upon extracellular matrix and cell type

    Energy Technology Data Exchange (ETDEWEB)

    Medina, D.; Oborn, C.J. (Baylor College of Medicine, Houston, TX (USA)); Li, M.L.; Bissell, M.J. (Univ. of California, Berkeley (USA))

    1987-09-01

    The COMMA-D mammary cell line exhibits mammary-specific functional differentiation under appropriate conditions in cell culture. The cytologically heterogeneous COMMA-D parental line and the clonal lines DB-1, TA-5, and FA-1 derived from the COMMA-D parent were examined for similar properties of functional differentiation. In monolayer cell culture, the cell lines DB-1, TA-5, FA-1, and MA-4 were examined for expression of mammary-specific and epithelial-specific proteins by an indirect immunofluorescence assay. The clonal cell lines were relatively homogeneous in their respective staining properties and seemed to represent three subpopulations found in the heterogeneous parental COMMA-D lines. None of the four clonal lines appeared to represent myoepithelial cells. The cell lines were examined for expression of {beta}-casein mRNA in the presence or absence of prolactin. The inducibility of {beta}-casein in the COMMA-D cell line was further enhanced by a reconstituted basement membrane preparation enriched in laminin, collagen IV, and proteoglycans. These results support the hypothesis that the functional response of inducible mammary cell populations is a result of interaction among hormones, multiple extracellular matrix components, and specific cell types.

  12. How does oil type determine emulsion characteristics in concentrated Na-caseinate emulsions?

    Science.gov (United States)

    Tan, Hui Lin; McGrath, Kathryn M

    2013-08-01

    Macroscopic properties and ensemble average diffusion of concentrated (dispersed phase 50-60 wt%) Na-caseinate-stabilised emulsions for three different oils (soybean oil, palm olein and tetradecane) were explored. On a volume fraction basis, pulsed gradient stimulated echo (PGSTE)-NMR data show that droplet dynamics for all three systems are similar within a region of the emulsion morphology diagram. The exact limits of the emulsion space depend however on which oil is considered. The reduced solubility of tetradecane in water, and Na-caseinate in tetradecane, result in the stabilisation of flocs during formulation. Floc formation is not observed when soybean oil or palm olein is used under identical emulsion formulation conditions. Linear rheology experiments provide indirect evidence that the local structure and the properties of the thin film interfacial domain of tetradecane emulsions vary from those of soybean oil and palm olein emulsions. Collectively these data indicate that protein/oil interactions within a system dominate over specific oil droplet structure and size distribution, which are similar in the three systems.

  13. Casein kinase 1δ/ε inhibitor PF-5006739 attenuates opioid drug-seeking behavior.

    Science.gov (United States)

    Wager, Travis T; Chandrasekaran, Ramalakshmi Y; Bradley, Jenifer; Rubitski, David; Berke, Helen; Mente, Scot; Butler, Todd; Doran, Angela; Chang, Cheng; Fisher, Katherine; Knafels, John; Liu, Shenping; Ohren, Jeff; Marconi, Michael; DeMarco, George; Sneed, Blossom; Walton, Kevin; Horton, David; Rosado, Amy; Mead, Andy

    2014-12-17

    Casein kinase 1 delta (CK1δ) and casein kinase 1 epsilon (CK1ε) inhibitors are potential therapeutic agents for a range of psychiatric disorders. The feasibility of developing a CNS kinase inhibitor has been limited by an inability to identify safe brain-penetrant compounds with high kinome selectivity. Guided by structure-based drug design, potent and selective CK1δ/ε inhibitors have now been identified that address this gap, through the design and synthesis of novel 4-[4-(4-fluorophenyl)-1-(piperidin-4-yl)-1H-imidazol-5-yl]pyrimidin-2-amine derivatives. PF-5006739 (6) possesses a desirable profile, with low nanomolar in vitro potency for CK1δ/ε (IC50 = 3.9 and 17.0 nM, respectively) and high kinome selectivity. In vivo, 6 demonstrated robust centrally mediated circadian rhythm phase-delaying effects in both nocturnal and diurnal animal models. Further, 6 dose-dependently attenuated opioid drug-seeking behavior in a rodent operant reinstatement model in animals trained to self-administer fentanyl. Collectively, our data supports further development of 6 as a promising candidate to test the hypothesis of CK1δ/ε inhibition in treating multiple indications in the clinic.

  14. Genetic polymorphism of β-lactoglobulin and κ-casein of cattle breeds in Croatia

    Directory of Open Access Journals (Sweden)

    Ante Ivanković

    2011-12-01

    Full Text Available Profitable milk production respects the interests of producers, processing industries, consumer requirements and welfare of animals. Development of new methods of direct gene analysis responsible for milk proteins polymorphism provide new tools to raise the profitability of milk production and dairy products through implementation of breed genetic profile in breeding program. Because of necessity to determinate genetic profiles of cattle breeds in Croatia using new analytical methods, the ratio of dominant allelic polymorphic variants of beta-lactoglobulin (β-Lg and kappa-casein (κ-CN is defined. The share of beta-lactoglobulin B variant is dominant in all investigated cattle breeds (>52.9 %. Kappa- casein allelic variant A is dominant in selected cattle breeds (60.7-76.4 %, while the share of B variant is significantly more presented in autochthonous cattle breeds (48.2-84.1 %. Knowledge about genetic profile of breeds due to studied polymorphic variants of milk proteins is useful in further breeding development and economic reaffirmation of cattle breeds, especially autochthonous ones.

  15. A sialic acid assay in isolation and purification of bovine k-casein glycomacropeptide: a review.

    Science.gov (United States)

    Nakano, Takuo; Ozimek, Lech

    2014-01-01

    Sialic acid is a carbohydrate moiety of k-casein glycomacropeptide (GMP), which is a 64 amino acid residue C-terminal sialylated phosphorylated glycopeptide released from k-casein by the action of chymosin during cheese making. GMP lacks aromatic amino acids including phenylalanine, tyrosine, and tryptophan. Because of its unique amino acid composition and various biological activities, GMP is thought to be a potential ingredient for dietetic foods (e.g., a food for PKU patients) and pharmaceuticals. Thus, increased attention has been given to the development of techniques to purify GMP. In this review, techniques of GMP purification described in patents and scientific research papers were introduced. A sialic acid assay is the important method to track GMP isolation and purification processes, for which the thiobarbituric acid reaction with 1-propanol as a chromophore extracting solvent is an inexpensive, practical and specific technique. Sephacryl S-200 gel filtration chromatography, cellulose acetate electrophoresis, and sodium dodecyl sulfate polyacrylamide gel electrophoresis are the major techniques to identify sialic acid specific to GMP. Sephacryl S-200 chromatography and cellulose acetate electrophoresis are also used to detect GMP sialic acid in whey pearmeate and whey added commercial margarine samples. Future research includes development of an economical industrial scale method to produce high purity GMP.

  16. Interfacial and foaming interactions between casein glycomacropeptide (CMP) and propylene glycol alginate.

    Science.gov (United States)

    Martinez, María J; Pizones Ruiz-Henestrosa, Víctor M; Carrera Sánchez, Cecilio; Rodríguez Patino, Juan M; Pilosof, Ana M R

    2012-06-15

    Proteins and polysaccharides are widely used in food formulation. While most of the proteins are surface active, only few polysaccharides can adsorb at the air-water interface; this is the case of propylene glycol alginates (PGA). It is known that casein glycomacropeptide (CMP), a bioactive polypeptide derived from κ-casein by the action of chymosin, presents a great foaming capacity but provides unstable foams. So, the objective of this work was to analyze the impact of mixing CMP and a commercial variety of PGA, Kelcoloid O (KO), on the interfacial and foaming properties at pH 7.0. It was determined the surface pressure isotherm, the dynamics of adsorption and the foaming properties for CMP, KO and the mixed system CMP-KO. CMP dominated the surface pressure of CMP-KO mixed system. The presence of KO synergistically improved the viscoelastic properties of surface film. The foaming capacity of CMP was altered by KO. KO foam presented a higher stability than CMP foam and it controlled the stability against drainage and the initial collapse in the mixed foam.

  17. Affinity chromatography matrices for depletion and purification of casein glycomacropeptide from bovine whey.

    Science.gov (United States)

    Baieli, María F; Urtasun, Nicolás; Martinez, María J; Hirsch, Daniela B; Pilosof, Ana M R; Miranda, María V; Cascone, Osvaldo; Wolman, Federico J

    2017-01-01

    Casein glycomacropeptide (CMP) is a 64- amino acid peptide found in cheese whey, which is released after κ-casein specific cleavage by chymosin. CMP lacks aromatic amino acids, a characteristic that makes it usable as a nutritional supplement for people with phenylketonuria. CMP consists of two nonglycosylated isoforms (aCMP A and aCMP B) and its different glycosylated forms (gCMP A and gCMP B). The most predominant carbohydrate of gCMP is N-acetylneuraminic acid (sialic acid). Here, we developed a CMP purification process based on the affinity of sialic acid for wheat germ agglutinin (WGA). After formation of chitosan beads and adsorption of WGA, the agglutinin was covalently attached with glutaraldehyde. Two matrices with different WGA density were assayed for CMP adsorption. Maximum adsorption capacities were calculated according to the Langmuir model from adsorption isotherms developed at pH 7.0, being 137.0 mg/g for the matrix with the best performance. In CMP reduction from whey, maximum removal percentage was 79% (specifically 33.7% of gCMP A and B, 75.8% of aCMP A, and 93.9% of aCMP B). The CMP was recovered as an aggregate with an overall yield of 64%. Therefore, the matrices developed are promising for CMP purification from cheese whey. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:171-180, 2017.

  18. Impact of cationic surfactant on the self-assembly of sodium caseinate.

    Science.gov (United States)

    Vinceković, Marko; Curlin, Marija; Jurašin, Darija

    2014-08-27

    The impact of a cationic surfactant, dodecylammonium chloride (DDACl), on the self-assembly of sodium caseinate (SC) has been investigated by light scattering, zeta potential, and rheological measurements as well as by microscopy (transmission electron and confocal laser scanning microscopy). In SC dilute solutions concentration-dependent self-assembly proceeds through the formation of spherical associates and their aggregation into elongated structures composed of connected spheres. DDACl interacts with SC via its hydrophilic and hydrophobic groups, inducing changes in SC self-assembled structures. These changes strongly depend on the surfactant aggregation states (monomeric or micellar) as well as concentration ratio of both components, leading to the formation of soluble and insoluble complexes of nano- to microdimensions. DDACl monomers interact with SC self-assembled entities in a different way compared to their micelles. Surfactant monomers form soluble complexes (similar to surfactant mixed micelles) at lower SC concentration but insoluble gelatinous complexes at higher SC concentration. At surfactant micellar concentration soluble complexes with casein chains wrapped around surfactant micelles are formed. This study suggests that the use of proper cationic surfactant concentration will allow modification and control of structural changes of SC self-assembled entities.

  19. Treatment of post-orthodontic white spot lesions with casein phosphopeptide-stabilised amorphous calcium phosphate.

    Science.gov (United States)

    Bröchner, Ann; Christensen, Carsten; Kristensen, Bjarne; Tranæus, Sofia; Karlsson, Lena; Sonnesen, Liselotte; Twetman, Svante

    2011-06-01

    This study aims to investigate the effect of topical applications of 10% casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on white spot lesions (WSL) detected after treatment with fixed orthodontic appliances. Sixty healthy adolescents with ≥1 clinically visible WSL at debonding were recruited and randomly allocated to a randomised controlled trial with two parallel groups. The intervention group was instructed to topically apply a CPP-ACP -containing agent (Tooth Mousse, GC Europe) once daily and the subjects of the control group brushed their teeth with standard fluoride toothpaste. The intervention period was 4 weeks and the endpoints were quantitative light-induced fluorescence (QLF) on buccal surfaces of the upper incisors, cuspids and first premolars and visual scoring from digital photos. The attrition rate was 15%, mostly due to technical errors, and 327 lesions were included in the final evaluation. A statistically significant (p white spot lesions after debonding of orthodontic appliances with a casein phosphopeptide-stabilised amorphous calcium phosphate agent resulted in significantly reduced fluorescence and a reduced area of the lesions after 4 weeks as assessed by QLF. The improvement was however not superior to the "natural" regression following daily use of fluoride toothpaste.

  20. Is gluten free and casein free (GFCF diet effective for individuals with autism?

    Directory of Open Access Journals (Sweden)

    Indah S. Widyahening

    2011-05-01

    Full Text Available Background: Even though the etiology of autistic spectrum disorder (ASD has not been clearly known, various types of therapies have been offered. One of the most popular therapies is Gluten Free and Casein Free Diet – GFCF diet.Methods: A structured internet literature search was conducted using Pubmed and Cochrane library. Titles and abstracts were screened using predetermined selection criteria. Critical appraisal was conducted based on standard criteria for relevance, validity, and levels of evidence.Results: Based on relevance, only four out of twelve selected articles can be used; one is a systematic review and three randomized controlled trials (RCTs. Several methodological problems which could lead to over-estimation of the effect were found in the studies including poor randomization and selective drop-out. Risk of under-estimation of report due to small number of participants and in-adequate duration of intervention was also found. Small to moderate improvement were found in some outcome measured including overall autistic traits, social isolation, and the ability in communication and interaction. However, insignificant differences also found in some area such as individual’s behavior, cognitive and motor function.Conclusion: Available studies fail to provide sufficiently credible and strong evidence to recommend the practice of GFCF diet in treating autism. (Med J Indones 2011; 20:114-8Keywords: autism, gluten free and casein free diet

  1. Phosphorylation of αS1-casein is regulated by different genes.

    Science.gov (United States)

    Bijl, E; van Valenberg, H J F; Huppertz, T; van Hooijdonk, A C M; Bovenhuis, H

    2014-11-01

    Casein phosphorylation is a posttranslational modification catalyzed by kinase enzymes that attach phosphate groups to specific AA in the protein sequence. This modification is one of the key factors responsible for the stabilization of calcium phosphate nanoclusters in casein micelles and for the internal structure of the casein micelles. α(S1)-Casein (α(s1)-CN) is of special interest because it constitutes up to 40% of the total casein fraction in milk, and it has 2 common phosphorylation states, with 8 (α(S1)-CN-8P) and 9 (α(S1)-CN-9P) phosphorylated serine residues. Factors affecting this variation in the degree of phosphorylation are not currently known. The objective of this research was to determine the genetic background of α(S1)-CN-8P and α(S1)-CN-9P. The genetic and phenotypic correlation between α(S1)-CN-8P and α(S1)-CN-9P was low (0.18 and 0.19, respectively). This low genetic correlation suggests a different genetic background. These differences were further investigated by means of a genome-wide association study, which showed that both α(S1)-CN-8P and α(S1)-CN-9P were affected by a region on Bos taurus autosome (BTA) 6, but only α(S1)-CN-8P was affected by a region on BTA11 that contains the gene that encodes for β-lactoglobulin (β-LG), and only α(S1)-CN-9P was affected by a region on BTA14 that contains the diacylglycerol acyltransferase 1 (DGAT1) gene. Estimated effects of β-LG protein genotypes showed that only α(S1)-CN-8P was associated with the β-LG A/B polymorphism (g.1772G>A and g.3054C>T); the AA genotype of β-LG was associated with a lower concentration of α(S1)-CN-8P (-0.32% wt/wt) than the BB genotype (+0.41% wt/wt). Estimated effects of DGAT1 K232A genotypes showed that only α(S1)-CN-9P was associated with the DGAT1 gene polymorphism; DGAT1 AA genotype was associated with a higher α(S1)-CN-9P concentration (+0.53% wt/wt) than the DGAT1 KK genotype (-0.44% wt/wt). The results give insight in phosphorylation of α(S1

  2. Casein kinases

    DEFF Research Database (Denmark)

    Issinger, O G

    1993-01-01

    subunits are highly conserved during evolution. The relationship between CK-2 alpha from humans and plants is still 73%. Similar relationships are reported for the beta-subunit. Chromosomal assignment of CK-2 alpha shows two gene loci, one of which is a pseudogene. They are located on different chromosomes......, no genetic changes are necessarily involved; the observed changes may be entirely due to a signal transduction pathway where CK-2 could be phosphorylated by another kinase(s). CK-2 cDNAs from various organisms have been isolated and characterized. From the deduced amino acid sequence it turns out that CK-2......-subunit affecting: (i) stability, (ii) enzyme specificity and (iii) enzyme activity. The question where CK-2 and its subunits are located throughout the cell cycle has also been addressed, mainly because of the large discrepancies that still exist between results obtained by different investigators. Tissue...

  3. Probing the characteristics of casein as green binder for non-aqueous electrochemical double layer capacitors' electrodes

    Science.gov (United States)

    Varzi, Alberto; Raccichini, Rinaldo; Marinaro, Mario; Wohlfahrt-Mehrens, Margret; Passerini, Stefano

    2016-09-01

    Casein from bovine milk is evaluated in this work as binding agent for electrochemical double layer capacitors (EDLCs) electrodes. It is demonstrated that casein provides excellent adhesion strength to the current collector (1187 kPa compared to 51 kPa achieved with PVdF), thus leading to mechanically stable electrodes. At the same time, it offers high thermal stability (above 200 °C) and electrochemical stability in organic electrolytes. Apparently though, the casein-based electrodes offer lower electronic conductivity than those based on other state-of-the-art binders, which can limit the rate performance of the resulting EDLC. In the attempt of improving the electrochemical performance, it is found that the application of a pressing step can solve this issue, leading to excellent rate capability (up to 84% capacitance retention at 50 mA cm-2) and cycling stability (96.8% after 10,000 cycles at 10 mA cm-2) in both PC- and ACN-based electrolytes. Although the adhesive power casein is known since ancient times, this report presents the first proof of concept of its employment in electrochemical power sources.

  4. RNA helicase DDX3 is a regulatory subunit of casein kinase 1 in Wnt-beta-catenin signaling

    NARCIS (Netherlands)

    Cruciat, C.M.; Dolde, C.; de Groot, R.E.; Ohkawara, B.; Reinhard, C.; Korswagen, H.C.; Niehrs, C.

    2013-01-01

    Casein kinase 1 (CK1) members play key roles in numerous biological processes. They are considered "rogue" kinases, because their enzymatic activity appears unregulated. Contrary to this notion, we have identified the DEAD-box RNA helicase DDX3 as a regulator of the Wnt-beta-catenin network, where i

  5. Possible mechanisms behind the differential effects of soy protein and casein feedings on colon cancer biomarkers in the rat

    NARCIS (Netherlands)

    Vis, E.H.; Geerse, G.J.; Klaassens, E.S.; Boekel, van M.A.J.S.; Alink, G.M.

    2005-01-01

    In the present studies, several hypotheses were tested to explain previously reported differential effects of soy and casein on colon cancer biomarkers like cell proliferation, fecal fat, fecal bile acid, alkaline phosphatase, and magnesium excretion in rats. In Study 1, the effect of methionine, a

  6. Nutritional Impact of a Gluten-Free Casein-Free Diet in Children with Autism Spectrum Disorder

    Science.gov (United States)

    Marí-Bauset, Salvador; Llopis-González, Agustín; Zazpe, Itziar; Marí-Sanchis, Amelia; Suárez-Varela, María Morales

    2016-01-01

    We compared anthropometric values, nutrient intake, the Healthy Eating Index and food variety in children with autism spectrum disorder (ASD), 20 on a gluten-free casein-free (GFCF) diet and 85 on a regular diet in Valencia (Spain) using 3-days food diaries. Those on the GFCF diet had a lower weight, body mass index, and total energy, pantothenic…

  7. EFFECT OF CASEIN-BASED SEMISYNTHETIC FOOD ON RENAL ACID EXCRETION AND ACID-BASE STATE OF BLOOD IN DOGS

    NARCIS (Netherlands)

    ZIJLSTRA, WG; LANGBROEK, AJM; KRAAN, J; RISPENS, P; NIJMEIJER, A

    1995-01-01

    Urinary acid excretion and blood acid-base stare were determined in dogs fed a casein-based semi-synthetic food (SSF), to which different amounts of salts had been added, in comparison with feeding normal dog food. Net acid excretion (NAE) and inorganic acid excretion (IAE) increased during SSF feed

  8. Influence of calcium chelators on concentrated micellar casein solutions : from micellar structure to viscosity and heat stability

    NARCIS (Netherlands)

    Kort, de E.J.P.

    2012-01-01

    In practice it is challenging to prepare a concentrated medical product with high heat stability
    and low viscosity. Calcium chelators are often added to dairy products to improve heat stability,
    but this may increase viscosity through interactions with the casein proteins. The aim of thi

  9. Whey Protein Delays Gastric Emptying and Suppresses Plasma Fatty Acids and Their Metabolites Compared to Casein, Gluten, and Fish Protein

    DEFF Research Database (Denmark)

    Stanstrup, Jan; Schou, Simon S; Holmer-Jensen, Jens

    2014-01-01

    Whey protein has been demonstrated to improve fasting lipid and insulin response in overweight and obese individuals. To establish new hypotheses for this effect and to investigate the impact of stomach emptying, we compared plasma profiles after intake of whey isolate (WI), casein, gluten (GLU...

  10. Gluten-Free and Casein-Free Diets in the Treatment of Autism Spectrum Disorders: A Systematic Review

    Science.gov (United States)

    Mulloy, Austin; Lang, Russell; O'Reilly, Mark; Sigafoos, Jeff; Lancioni, Giulio; Rispoli, Mandy

    2010-01-01

    This paper systematically reviews research on the effects of gluten-free and/or casein-free (GFCF) diets in the treatment of ASD. Database, hand, and ancestry searches identified 15 articles for review. Each study was analyzed and summarized in terms of (a) participants, (b) specifics of the intervention, (c) dependent variables, (d) results, and…

  11. Addendum to "Gluten-Free and Casein-Free Diets in Treatment of Autism Spectrum Disorders: A Systematic Review"

    Science.gov (United States)

    Mulloy, Austin; Lang, Russell; O'Reilly, Mark; Sigafoos, Jeff; Lancioni, Giulio; Rispoli, Mandy

    2011-01-01

    Shortly after the publication of our literature review on gluten-free and casein-free (GFCF) diets in the treatment of autism spectrum disorders (ASD; Mulloy et al., 2010), Whiteley et al. (2010) published the results of experimental evaluation of a GFCF diet. To update our previous literature review, we herein provide an analysis of the Whiteley…

  12. Role of the beta subunit of casein kinase-2 on the stability and specificity of the recombinant reconstituted holoenzyme

    DEFF Research Database (Denmark)

    Meggio, F; Boldyreff, B; Marin, O;

    1992-01-01

    Recombinant human alpha subunit from casein kinase-2 (CK-2) was subjected, either alone or in combination with recombinant human beta subunit, to high temperature, tryptic digestion and urea treatment. In all three cases, it was shown that the presence of the beta subunit could drastically reduce...

  13. The effects of transglutaminase catalysis on the functional and immunoglobulin binding properties of peanut flour dispersions containing casein.

    Science.gov (United States)

    The functionality of light roasted peanut flour (PF) dispersions containing supplemental casein (CN), was altered after polymerization with microbial transglutaminase (TGase). The formation of high molecular weight covalent cross-links was observed with potential formation of PF-PF, PF-CN, and CN-CN...

  14. Enzymatic hydrolysis of whey and casein protein- effect on functional, rheological, textural and sensory properties of breads.

    Science.gov (United States)

    Gani, Adil; Broadway, A A; Masoodi, Farooq Ahmad; Wani, Ali Abas; Maqsood, Sajid; Ashwar, Bilal Ahmad; Shah, Asima; Rather, Sajad Ahmad; Gani, Asir

    2015-12-01

    Milk proteins were hydrolyzed by papain and their effect on the rheological, textural and sensory properties of bread were investigated. Water absorption capacity, emulsification capacity, foam volume, foam stability and solubility of Whey and casein protein concentrates and their hydrolysates were determined. The farinograph parameters of wheat flour and blends of wheat flour with casein and whey protein and their hydrolysates were determined to evaluate changes in water absorption capacity, dough development time, dough stability time and mixing tolerance index. The incorporation of WPC, casein and their hydrolysates up to the level of 5 % showed dough properties comparable to control. It was also found that 5 % level incorporation of milk proteins and their hydrolysates have no drastic effect on physical and sensory attributes of bread. The pasting properties showed significant decrease (p ≤ 0.05) when compared with wheat flour at all levels of addition of whey and casein protein concentrates and hydrolysates. Scanning electron microscopy of bread samples shows disruption in the well-defined protein - starch complex of wheat flour bread and the structure of gluten was weak as the concentration of whey protein increases in the wheat flour bread.

  15. Fat digestion in veal calves fed milk replacers low or high in calcium and containing either casein or soy protein isolate.

    Science.gov (United States)

    Yuangklang, C; Wensing, Th; Van den Broek, L; Jittakhot, S; Beynen, A C

    2004-04-01

    The hypothesis tested was that the inhibitory effect of dietary soy protein versus casein on fat digestion in veal calves would be smaller when diets were fed with high instead of low calcium content. Male calves, 1 wk of age, were fed 1 of 4 experimental milk replacers in a 2 x 2 factorial design. There were 19 animals per dietary group. The milk replacers contained either casein or soy protein isolate as variable protein source and were either low or high in calcium. Body weight gain was not significantly affected by the experimental diets. Soy protein isolate versus casein significantly reduced apparent fat digestibility. High versus low calcium intake also depressed fat digestion. The protein effect was smaller (2.9% units) for the high than the low calcium diets (3.6% units), but the interaction did not reach statistical significance. Soy protein isolate versus casein raised fecal bile acid excretion and so did high versus low calcium intake. The difference in bile acid excretion between the soy and casein containing diets was significantly greater for the high than low calcium diets. The absorption of phosphorus, calcium, and magnesium was higher for the casein diets than for the soy-containing diets. This study shows for the first time that soy protein isolate versus casein depressed fat digestion and raised fecal bile acid excretion in veal calves.

  16. Using self-consistent-field theory to understand enhanced steric stabilization by casein-like copolymers at low surface coverage in mixed protein layers.

    Science.gov (United States)

    Parkinson, Emma L; Ettelaie, Rammile; Dickinson, Eric

    2005-01-01

    We present a statistical mechanical approach to predicting the properties of mixed copolymer layers using the Scheutjens-Fleer self-consistent-field theory. Our model copolymers are based on the primary structures of the major bovine casein monomers, alpha(s1)-casein and beta-casein. Numerical calculations have been carried out to determine the polymer segment density profiles at an isolated hydrophobic surface and the interaction forces as a pair of polymer-coated surfaces is brought to close interlayer separation. For a copolymer model containing hydrophilic and hydrophobic segments, we show how the steric stabilizing capacity of a casein-like macromolecule at very low surface coverage is enhanced in the presence of a thin dense layer of shorter tethered amphiphilic chains. Using a more refined protein model, which also distinguishes between the charged and uncharged hydrophilic segments along the chain, we clearly demonstrate that the enhanced steric repulsion from beta-casein exceeds that from alpha(s1)-casein. These calculations explain how the replacement of just a few percent of beta-lactoglobulin by casein can inhibit the heat-induced thickening and flocculation behavior observed experimentally with some whey protein-stabilized oil-in-water emulsions.

  17. Viability of the microencapsulation of a casein hydrolysate in lipid microparticles of cupuacu butter and stearic acid

    Directory of Open Access Journals (Sweden)

    Samantha Cristina Pinho

    2013-04-01

    Full Text Available Normal 0 21 false false false PT-BR X-NONE X-NONE Solid lipid microparticles produced with a mixture of cupuacu butter and stearic acid were used to microencapsulate a commercial casein hydrolysate (Hyprol 8052. The composition of the lipid matrix used for the production of the lipid microparticles was chosen according to data on the wide angle X-ray diffraction (WAXD and differential scanning calorimetry (DSC of bulk lipid mixtures, which indicated that the presence of 10 % cupuacu butter was sufficient to significantly change the crystalline arrangement of pure stearic acid. Preliminary tests indicated that a minimum proportion of 4 % of surfactant (polysorbate 80 was necessary to produce empty spherical lipid particles with average diameters below 10 mm. The lipid microparticles were produced using 20 % cupuacu butter and 80 % stearic acid and then stabilized with 4 % of polysorbate 80, exhibiting an encapsulation efficiency of approximately 74 % of the casein hydrolysate. The melting temperature of the casein hydrolysate-loaded lipid microparticles was detected at 65.2 °C, demonstrating that the particles were solid at room temperature as expected and indicating that the incorporation of peptides had not affected their thermal behavior. After 25 days of storage, however, there was a release of approximately 30 % of the initial amount of encapsulated casein hydrolysate. This release was not thought to have been caused by the liberation of encapsulated casein hydrolysate. Instead, it was attributed to the possible desorption of the adsorbed peptides present on the surface of the lipid microparticles.

  18. Composite β-κ-casein genotypes and their effect on composition and coagulation of milk from Estonian Holstein cows.

    Science.gov (United States)

    Vallas, M; Kaart, T; Värv, S; Pärna, K; Jõudu, I; Viinalass, H; Pärna, E

    2012-11-01

    The objective of this study was to estimate the effect of composite β-κ-CN genotypes on milk coagulation and composition traits, and on the additive genetic variation of these traits in Estonian Holstein dairy cattle. A total of 23,970 milk samples, repeated measurements from the first to third lactation from 2,859 Estonian Holstein cows from 78 herds across the country, were analyzed for milk yield, milk fat and protein percentages, somatic cell count, and milk coagulation properties (milk coagulation time and curd firmness). Each cow had at least 3 measurements per lactation. Two single-trait random regression animal models were fitted for the traits studied. The first model considered fixed effects of year-season of sampling and year-season of calving, calving age (nested within lactation), sample age (only for milk coagulation traits) and days in milk, and random herd, additive genetic, and permanent environmental effects. The animal and permanent environmental effects were modeled over the lactation period by using Legendre polynomials. The second model had the additional fixed β-κ-casein effect in the form of a third-order Legendre polynomial. The 2 most frequent β-κ-casein composite genotypes were A2A2AA and A1A2AA, both with prevalence greater than 20%. Percentages of the remaining 31 genotypes were less than 8%, including 20 genotypes with percentages less than 1%. The β-κ-casein genotype-specific lactation curves were significantly different for milk coagulation traits and milk protein percentage. The B variant of κ-casein showed a favorable effect on both milk coagulation traits, whereas the IB haplotype had an increasing effect on curd firmness and protein percentage. Inclusion of the β-κ-casein genotype effects in the model resulted in decreases in the mean additive genetic variations for milk coagulation time and curd firmness of 12.9 and 51.1%, respectively.

  19. Casein Films: The Effects of Formulation, Environmental Conditions and the Addition of Citric Pectin on the Structure and Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Laetitia M. Bonnaillie

    2014-07-01

    Full Text Available Thin casein films for food packaging applications reportedly possess good strength and low oxygen permeability, but low elasticity and high sensitivity to moisture. Modifying the films to target specific behaviors depending on environmental conditions can enable a variety of commercial applications for casein-based films. The mechanical properties of solvent-cast (15% solids calcium-caseinate/glycerol films (CaCas:Gly ratio of 3:1 were characterized as a function of processing and environmental conditions, including film thickness, solution formulation and ambient humidity (from 22% to 70% relative humidity (RH at ~20 °C. At constant RH, the elongation at break (EAB had a strong positive dependence on the film thickness. When RH increased, the tensile strength (TS and modulus (E decreased approximately linearly, while EAB increased. From 0.05% to 1% (w/w of citric pectin (CP was then incorporated into CaCas/Gly films following seven different formulations (mixing sequences, to alter the protein network and to evaluate the effects of CP on the tensile properties of CaCas/Gly/CP films. At constant film thickness and ~60% RH, the addition of 0.1% or 1.0% CP to the films considerably increased or decreased EAB, TS and E in different directions and to different extents, depending on the formulation, while optical micrographs also showed vastly differing network configurations, suggesting complex formulation- and stoichiometry-dependent casein-pectin interactions within the dried films. Depending on the desired film properties and utilization conditions, pectin may be a useful addition to casein film formulations for food packaging applications.

  20. Small intestinal digestion of raw cornstarch in cattle consuming a soybean hull-based diet is improved by duodenal casein infusion.

    Science.gov (United States)

    Brake, D W; Titgemeyer, E C; Bailey, E A; Anderson, D E

    2014-09-01

    Six duodenally and ileally cannulated steers were used in 3 sequential studies to measure 1) basal nutrient flows from a soybean hull-based diet, 2) small intestinal digestibility of raw cornstarch continuously infused into the duodenum, and 3) responses of small intestinal starch digestion to duodenal infusion of 200 or 400 g/d casein. Our objective was to evaluate responses in small intestinal starch digestion in cattle over time and to measure responses in small intestinal starch digestion to increasing amounts of MP. On average, cattle consumed 3.7 kg/d DM, 68 g/d dietary N, and 70 g/d dietary starch. Starch flow to the duodenum was small (38 g/d), and N flow was 91 g/d. Small intestinal digestibility of duodenal N was 57%, and small intestinal digestion of duodenal starch flow was extensive (92%). Small intestinal starch digestibility was 34% when 1.5 kg/d raw cornstarch was continuously infused into the duodenum. Subsequently, cattle were placed in 1 of 2 replicated Latin squares that were balanced for carryover effects to determine response to casein infusions and time required for adaptation. Duodenal infusion of casein linearly increased (P ≤ 0.05) small intestinal starch digestibility, and small intestinal starch digestion adapted to infusion of casein in 6 d. Ethanol-soluble starch and unpolymerized glucose flowing to the ileum increased linearly (P ≤ 0.05) with increasing infusion of casein. Plasma cholecystokinin was not affected by casein infusion, but circulating levels of glucose were increased by casein supplementation (P ≤ 0.05). Responses in small intestinal starch digestion in cattle adapted to casein within 6 d, and increases in duodenal supply of casein up to 400 g/d increased small intestinal starch digestion in cattle.

  1. Ligand-protein interactions of selective casein kinase 1δ inhibitors.

    Science.gov (United States)

    Mente, Scot; Arnold, Eric; Butler, Todd; Chakrapani, Subramanyam; Chandrasekaran, Ramalakshmi; Cherry, Kevin; DiRico, Ken; Doran, Angela; Fisher, Katherine; Galatsis, Paul; Green, Michael; Hayward, Matthew; Humphrey, John; Knafels, John; Li, Jianke; Liu, Shenping; Marconi, Michael; McDonald, Scott; Ohren, Jeff; Paradis, Vanessa; Sneed, Blossom; Walton, Kevin; Wager, Travis

    2013-09-12

    Casein kinase 1δ (CK1δ) and 1ε (CK1ε) are believed to be necessary enzymes for the regulation of circadian rhythms in all mammals. On the basis of our previously published work demonstrating a CK1ε-preferring compound to be an ineffective circadian clock modulator, we have synthesized a series of pyrazole-substitued pyridine inhibitors, selective for the CK1δ isoform. Additionally, using structure-based drug design, we have been able to exploit differences in the hinge region between CK1δ and p38 to find selective inhibitors that have minimal p38 activity. The SAR, brain exposure, and the effect of these inhibitors on mouse circadian rhythms are described. The in vivo evaluation of these inhibitors demonstrates that selective inhibition of CK1δ at sufficient central exposure levels is capable of modulating circadian rhythms.

  2. Quantitative analysis of complex casein hydrolysates based on chromatography and membrane

    Institute of Scientific and Technical Information of China (English)

    Qi Wei; Yu Yanjun; He Zhimin

    2006-01-01

    The enzymatic hydrolysates of casein are so complex that there is no effective method to do quantitative analysis.The common techniques,such as high performance chromatography and SDS-PAGE,can only carry out qualitative analysis.On the basis of membrane separation and high performance size exclusion chromatography (HPSEC),standard peptides with different molecular mass range were prepared,and the linear relationships between mass concentration of the standard peptides and the ultraviolet absorption of corresponding peak areas were established.Consequently,mass concentration of the different hydrolysates at different reaction times could be accurately calculated.The combination of chromatography and membrane separation is of great importance to the quantitative analysis of the complex hydrolysates,which can also be applied to the other macromolecular systems,such as carbohydrates.

  3. The gluten-free, casein-free diet in autism: an overview with clinical implications.

    Science.gov (United States)

    Elder, Jennifer Harrison

    The prevalence of classic autism and autism spectrum disorder (ASD) appears to be on the rise, and to date, there remains no clear etiology or cure. Out of desperation, many families are turning to new therapies and interventions discovered through various media sources and anecdotal reports from other parents. Unfortunately, many of these newer, well-publicized interventions have little empirical support. One of the most popular yet currently scientifically unproven interventions for ASD is the gluten-free, casein-free (GFCF) diet. Clinicians working with families of individuals with ASD are often asked for advice and find themselves unable to offer the most up-to-date and scientifically credible information. This article provides an overview of ASD and the GFCF diet, a summary and critique of current research findings, recommendations for future research, and practical advice for families to use in deciding if a trial of the GFCF diet is in the best interest of their child and family.

  4. Casein improves brachial and central aortic diastolic blood pressure in overweight adolescents: a randomised, controlled trial

    DEFF Research Database (Denmark)

    Arnberg, Karina; Larnkjær, Anni; Michaelsen, Kim F.

    2013-01-01

    of water, skimmed milk, whey or casein for 12 weeks. The milk-based test drinks contained 35 g protein/l. The effects were compared with the water group and a pretest control group consisting of thirty-two of the adolescents followed 12 weeks before the start of the intervention. Outcomes were brachial......Arterial stiffness, blood pressure (BP) and blood lipids may be improved by milk in adults and the effects may be mediated via proteins. However, limited is known about the effects of milk proteins on central aortic BP and no studies have examined the effects in children. Therefore, the present...... trial examined the effect of milk and milk proteins on brachial and central aortic BP, blood lipids, inflammation and arterial stiffness in overweight adolescents. A randomised controlled trial was conducted in 193 overweight adolescents aged 12–15 years. They were randomly assigned to drink 1 litre...

  5. Effect of Xanthan Gum on the Rheological Behavior and Microstructure of Sodium Caseinate Acid Gels

    Directory of Open Access Journals (Sweden)

    María E. Hidalgo

    2016-09-01

    Full Text Available The aim of this work was to study the effect of xanthan gum (XG on the gelation process of bovine sodium caseinate (NaCAS induced by acidification with glucono-δ-lactone (GDL and on the mixed acid gel microstructure. Before GDL addition, segregative phase separation was observed in all the NaCAS-XG mixtures evaluated. The gelation process was analyzed by using a fractional factorial experimental design. The images of the microstructure of the mixed acid gels were obtained by conventional optical microscopy and the mean diameter of the interstices was determined. Both the elastic character and the microstructure of the gels depended on the concentrations of XG added. As XG concentration increased, the kinetics of the gelation process was modified and the degree of compactness and elasticity component of the gel network increased. The microstructure of gels depends on the balance among thermodynamic incompatibility, protein gelation and NaCAS-XG interactions.

  6. The increasing of enamel calcium level after casein phosphopeptideamorphous calcium phosphate covering

    Directory of Open Access Journals (Sweden)

    Widyasri Prananingrum

    2012-06-01

    Full Text Available Background: Caries process is characterized by the presence of demineralization. Demineralization is caused by organic acids as a result of carbohydrate substrate fermentation. Remineralization is a natural repair process for non-cavitated lesions. Remineralization occurs if there are Ca2+ and PO43- ions in sufficient quantities. Casein-amorphous calcium phosphate phosphopeptide (CPP-ACP is a paste material containing milk protein (casein, that actually contains minerals, such as calcium and phosphate. The casein ability to stabilize calcium phosphate and enhance mineral solubility and bioavailability confers upon CPP potential to be biological delivery vehicles for calcium and phosphate. Purpose: The aim of this study was to determine the calcium levels in tooth enamel after being covered with CPP-ACP 2 times a day for 3, 14 and 28 days. Methods: Sample were bovine incisors of 3 year old cows divided into 4 groups, namely group I as control group, group II, III and IV as treatment groups covered with CPP-ACP 2 times a day. All of those teeth were then immersed in artificial saliva. Group II was immersed for 3 days, while group III was immersed for 14 days, and group IV was immersed for 28 days. One drop of CPP-ACP was used to cover the entire labial surface of teeth. The measurement of the calcium levels was then conducted by using titration method. All data were analyzed by One- Way ANOVA test with 5% degree of confidence. Results: The results showed significant difference of the calcium levels in tooth enamel of those groups after covered with CPP-ACP 2 times a day for 3, 14 and 28 days (p = 0.001. There is also significant difference of the calcium levels in tooth enamel of those treatment groups and the control group (p = 0.001. Conclusion: The calcium levels of tooth enamel are increased after covered with CPP-ACP 2 times a day for 3, 14 and 28 days.Latar belakang: Proses terjadinya karies gigi ditandai oleh adanya demineralisasi

  7. Heterogeneity of caprine beta-casein elucidated by RP-HPLC/MS: genetic variants and phosphorylations.

    Science.gov (United States)

    Neveu, Carole; Mollé, Daniel; Moreno, Javier; Martin, Patrice; Léonil, Joëlle

    2002-11-01

    Casein variants occurring in milks from goats homozygous at the alpha(s1)-Cn locus were separated and identified by an RP-HPLC/ESI-MS method. Preferential haplotypes arose as well as some particularities in posttranslational modifications. A new variant of caprine beta-Cn, named C, as well as the phosphorylations pattern of the protein were characterized by the combined use of peptide mass fingerprinting and sequencing by tandem mass spectrometry. The molecular mass of the new variant in its 6P form was measured as 23854 Da and it differs in a mono amino acid substitution, A177 --> V177, from the variant A. The phosphorylation pattern of caprine beta-Cn is homologous to bovine beta-Cn concerning the 5P located on Ser15, 17, 18, 19, 35 but it presents a specific additional phosphorylation site on Thr12 that is comparable to human beta-Cn phosphorylation located on Thr3.

  8. Circadian and pharmacological regulation of casein kinase I in the hamster suprachiasmatic nucleus

    Indian Academy of Sciences (India)

    Patricia V. Agostino; Santiago A. Plano; Diego A. Golombek

    2008-12-01

    In mammals, the mechanism for the generation of circadian rhythms and entrainment by light–dark (LD) cycles resides in the hypothalamic suprachiasmatic nuclei (SCN), and the principal signal that adjusts this biological clock with environmental timing is the light:dark cycle. Within the SCN, rhythms are generated by a complex of molecular feedback loops that regulate the transcription of clock genes, including per and cry. Posttranslational modification plays an essential role in the regulation of biological rhythms; in particular, clock gene phosphorylation by casein kinase I, both epsilon (CKI) and delta (CKI), regulates key molecular mechanisms in the circadian clock. In this paper, we report for the first time that CKI activity undergoes a significant circadian rhythm in the SCN (peaking at circadian time 12, the start of the subjective night), and its pharmacological inhibition alters photic entrainment of the clock, indicating that CKI may be a key element in this pathway.

  9. Drying Technology of Angiotensin Converting Enzyme Inhibitory Peptide Derived from Bovine Casein

    Institute of Scientific and Technical Information of China (English)

    JIANG Zhanmei; Hue Guicheng; TIAN Be

    2009-01-01

    Drying technology of angiotensin converting enzyme (ACE) inhibitory peptides derived from bovine casein was investigated. No significance was observed on ACE inhibitory activity of products prepared by spay drying and freeze drying (P>0.05). Spay drying was the best drying process for practical industry production. The inlet temperature ranged from 140℃ to 160℃ and the exit temperature ranged from 70℃ to 90℃ during the spay drying process. Under the optimal eonditious, scale-up of angiotensin converted enzyme inhibitory peptide from 1 L to 10 L and the experiment was successively conducted. Peptide yield was 29% and half inhibitory concentration(IC50) was 0.53g·L-1.

  10. Genetic polymorphism of the K-casein (CSN3 gene in goats reared in Southern Italy

    Directory of Open Access Journals (Sweden)

    Fabio Pilla

    2010-01-01

    Full Text Available K-casein (K-CN represents one of the most important proteins determining the manufacturing properties of milk,because of its essential role in micelle formation and stabilisation.Several genetic variants of K-CN have been described in goats. To investigate the occurrence of seven alleles and theirdistribution among breeds, a total of 170 animals, from six different breeds reared in Italy (Cilentana Nera, Derivata diSiria, Maltese, Jonica, Garganica and Cashmere, have been analysed in this paper by the primer extension method.Alleles A and B were found to be the most represented in all the analysed breeds; allele D is present only in Maltese andCashmere animals with a very low frequency; while allele G has been found in all but two (Garganica and Cashmerebreeds. Alleles C, E and F were not present in the material used for this study.

  11. IDENTIFICATION OF BETA-LACTOGLOBULIN AND KAPPA-CASEIN GENOTYPES IN CATTLE

    Directory of Open Access Journals (Sweden)

    TESIO C.D.

    2007-01-01

    Full Text Available Beta-lactoglobulin (b-Lg and kappa-casein (k-Cn are two of the most importantproteins in the mammals’ milk synthesized by the epithelial cells of the mammaryglands. They play a crucial role in the milk quality and coagulation process(production of cheese and butter. The PCR-RFLP test was performed to distinguishthe different alleles in a population of Romanian Black Spotted cattle, a dairy breed.Genetic polymorphism was detected by digestion with the endonucleases Hae III (b-Lg and Hinf I (k-Cn, followed by electrophoresis in agarose high resolution gelstained with ethidium bromide. Fifty DNA samples from Romanian Black Spottedbreed were analyzed for A and B variants. This simple PCR-RFLP test makesfeasible the inclusion of b-Lg and k-Cn genotypes in breeding plans and cattleselection.

  12. Isolation and characterization of recombinant human casein kinase II subunits alpha and beta from bacteria

    DEFF Research Database (Denmark)

    Grankowski, N; Boldyreff, B; Issinger, O G

    1991-01-01

    cDNA encoding the casein kinase II (CKII) subunits alpha and beta of human origin were expressed in Escherichia coli using expression vector pT7-7. Significant expression was obtained with E. coli BL21(DE3). The CKII subunits accounted for approximately 30% of the bacterial protein; however, most...... of the expressed proteins were produced in an insoluble form. The recombinant CKII alpha subunit was purified by DEAE-cellulose chromatography, followed by phosphocellulose and heparin-agarose chromatography. The recombinant CKII beta subunit was extracted from the insoluble pellet and purified in a single step...... on phosphocellulose. From 10 g bacterial cells, the yield of soluble protein was 12 mg alpha subunit and 5 mg beta subunit. SDS/PAGE analysis of the purified recombinant proteins indicated molecular masses of 42 kDa and 26 kDa for the alpha and beta subunits, respectively, in agreement with the molecular masses...

  13. Formulation and characterization of nanoencapsulated curcumin using sodium caseinate and its incorporation in ice cream.

    Science.gov (United States)

    Kumar, Deep Diyuti; Mann, Bimlesh; Pothuraju, Ramesh; Sharma, Rajan; Bajaj, Rajesh; Minaxi

    2016-01-01

    In the present investigation, the preparation and characterization of a curcumin nanoemulsion with milk protein (sodium caseinate) and its incorporation into ice cream were undertaken. Among the different combinations, the most stable formulation was observed using milk fat (8%), medium chain triglycerides (2%), curcumin (0.24%) and sodium caseinate (6%) with a mean particle size of 333.8 ± 7.18 nm, a zeta potential of -44.1 ± 0.72 mV and an encapsulation efficiency of 96.9 ± 0.28%. The effect of different processing conditions (heating, pH and ionic strength) on the particle size distribution and zeta potential of the nanoemulsion was evaluated. During heat treatment, the particle size of the nanoemulsion was increased from 333.8 ± 7.18 to 351.1 ± 4.04 nm. The nanoemulsion was destabilized at pH 4.6 and the particle size increased above and below pH 5.0. However, there was a slight increase in the particle size with a change in the ionic concentration. The release kinetics data suggested that in simulated gastro-intestinal digestion, the nanoemulsion was stable against pepsin digestion (a 5.25% release of curcumin), while pancreatic action led to a 16.12% release of curcumin from the nanoemulsion. Finally, our formulation was successfully incorporated into ice cream and the sensory attributes were evaluated. No significant difference was observed in the scores of the sensory attributes between the control and ice cream prepared with a curcumin nanoemulsion. Moreover, the encapsulation efficiency of the curcumin incorporated into the ice cream was 93.7%, which indicates that it can withstand the processing conditions. The findings suggest that ice cream is a suitable dairy product for the delivery of lipophilic bioactive components (curcumin) which can be used for therapeutic purposes.

  14. Novel ionically crosslinked casein nanoparticles for flutamide delivery: formulation, characterization, and in vivo pharmacokinetics

    Directory of Open Access Journals (Sweden)

    Elzoghby AO

    2013-05-01

    Full Text Available Ahmed O Elzoghby,1 Maged W Helmy,2 Wael M Samy,1,3 Nazik A Elgindy11Department of Industrial Pharmacy, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; 2Department of Pharmacology and Toxicology, Faculty of Pharmacy, Pharos University, Alexandria, Egypt; 3Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, Beirut Arab University, Beirut, LebanonAbstract: A novel particulate delivery matrix based on ionically crosslinked casein (CAS nanoparticles was developed for controlled release of the poorly soluble anticancer drug flutamide (FLT. Nanoparticles were fabricated via oil-in-water emulsification then stabilized by ionic crosslinking of the positively charged CAS molecules below their isoelectric point, with the polyanionic crosslinker sodium tripolyphosphate. With the optimal preparation conditions, the drug loading and incorporation efficiency achieved were 8.73% and 64.55%, respectively. The nanoparticles exhibited a spherical shape with a size below 100 nm and a positive zeta potential (+7.54 to +17.3 mV. FLT was molecularly dispersed inside the nanoparticle protein matrix, as revealed by thermal analysis. The biodegradability of CAS nanoparticles in trypsin solution could be easily modulated by varying the sodium tripolyphosphate crosslinking density. A sustained release of FLT from CAS nanoparticles for up to 4 days was observed, depending on the crosslinking density. After intravenous administration of FLT-CAS nanoparticles into rats, CAS nanoparticles exhibited a longer circulation time and a markedly delayed blood clearance of FLT, with the half-life of FLT extended from 0.88 hours to 14.64 hours, compared with drug cosolvent. The results offer a promising method for tailoring biodegradable, drug-loaded CAS nanoparticles as controlled, long-circulating drug delivery systems of hydrophobic anticancer drugs in aqueous vehicles.Keywords: casein nanoparticles, ionic crosslinking, biodegradability

  15. Autoantibodies to αS1-casein are induced by breast-feeding.

    Directory of Open Access Journals (Sweden)

    Klaudia Petermann

    Full Text Available BACKGROUND: The generation of antibodies is impaired in newborns due to an immature immune system and reduced exposure to pathogens due to maternally derived antibodies and placental functions. During nursing, the immune system of newborns is challenged with multiple milk-derived proteins. Amongst them, caseins are the main constituent. In particular, human αS1-casein (CSN1S1 was recently shown to possess immunomodulatory properties. We were thus interested to determine if auto-antibodies to CSN1S1 are induced by breast-feeding and may be sustained into adulthood. METHODS: 62 sera of healthy adult individuals who were (n = 37 or were not (n = 25 breast-fed against human CSN1S1 were investigated by a new SD (surface display-ELISA. For cross-checking, these sera were tested for anti Epstein-Barr virus (EBV antibodies by a commercial ELISA. RESULTS: IgG-antibodies were predominantly detected in individuals who had been nursed. At a cut-off value of 0.4, the SD-ELISA identified individuals with a history of having been breast-fed with a sensitivity of 80% and a specificity of 92%. Under these conditions, 35 out of 37 sera from healthy donors, who where breast-fed, reacted positively but only 5 sera of the 25 donors who were not breast-fed. The duration of breast-feeding was of no consequence to the antibody reaction as some healthy donors were only short term breast-fed (5 days minimum until 6 weeks maximum, but exhibited significant serum reaction against human CSN1S1 nonetheless. CONCLUSION: We postulate that human CSN1S1 is an autoantigen. The antigenicity is orally determined, caused by breast-feeding, and sustained into adulthood.

  16. Whey and casein labelled with L-[1-13C]-leucine and muscle protein synthesis: effect of resistance exercise and protein ingestion

    DEFF Research Database (Denmark)

    Reitelseder, Søren; Agergaard, Jakob; Doessing, Simon

    2011-01-01

    to a single bolus intake of whey or casein after performance of heavy resistance exercise. Young male individuals were randomly assigned to participate in two protein trials (n = 9) or one control trial (n = 8). Infusion of l-[1-(13)C]leucine was carried out, and either whey, casein (0.3 g/kg lean body mass......), or a noncaloric control drink was ingested immediately after exercise. l-[1-(13)C]leucine-labeled whey and casein were used while muscle protein synthesis (MPS) was assessed. Blood and muscle tissue samples were collected to measure systemic hormone and amino acid concentrations, tracer enrichments......, and myofibrillar protein synthesis. Western blots were used to investigate the Akt signaling pathway. Plasma insulin and branched-chain amino acid concentrations increased to a greater extent after ingestion of whey compared with casein. Myofibrillar protein synthesis was equally increased 1-6 h postexercise after...

  17. Rapid quantification of casein in skim milk using Fourier transform infrared spectroscopy, enzymatic perturbation, and multiway partial least squares: Monitoring chymosin at work

    DEFF Research Database (Denmark)

    Baum, Andreas; Hansen, P. W.; Nørgaard, Lars

    2016-01-01

    least squares regression. Because we observed casein-specific kinetic changes, the retrieved models were independent of the chemical background matrix and were therefore robust against possible covariance effects. We tested the robustness of the models by spiking the milk solutions with whey, calcium......In this study, we introduce enzymatic perturbation combined with Fourier transform infrared (FTIR) spectroscopy as a concept for quantifying casein in subcritical heated skim milk using chemometric multiway analysis. Chymosin is a protease that cleaves specifically caseins. As a result...... of hydrolysis, all casein proteins clot to form a creamy precipitate, and whey proteins remain in the supernatant. We monitored the cheese-clotting reaction in real time using FTIR and analyzed the resulting evolution profiles to establish calibration models using parallel factor analysis and multiway partial...

  18. Study on genetic variability at αS1 and αS2 casein loci in autochthonous goat populations of the Lombardy Alps

    Directory of Open Access Journals (Sweden)

    P. Crepaldi

    2011-03-01

    Full Text Available In cattle, sheep and goats (Hayes et al., 1993 the casein genes form a cluster, on the chromosome 6, of four tightly linked genes, whose sequence is: αS1-β-αS2-k (Threadgill and Womack, 1990; Ferretti et al., 1990; Gallagher et al., 1994; Rijnkles et al., 1997. For this reason the alleles at these loci are generally inherited all together (Di Stasio and Mariani, 2000, with low recombination frequency. Thus it is worth noting the importance of describing the casein haplotypes namely the inherited combination of closely linked alleles (King and Stansfield, 1985; Meuwissen and Goddard, 2001. The knowledge of the casein allele associations could be important for the selection. In goat milk the casein alleles are related to important differences in the level of synthesis of the respective gene products and in milk chemical-physical properties........

  19. The milk protein α-casein functions as a tumor suppressor via activation of STAT1 signaling, effectively preventing breast cancer tumor growth and metastasis.

    Science.gov (United States)

    Bonuccelli, Gloria; Castello-Cros, Remedios; Capozza, Franco; Martinez-Outschoorn, Ubaldo E; Lin, Zhao; Tsirigos, Aristotelis; Xuanmao, Jiao; Whitaker-Menezes, Diana; Howell, Anthony; Lisanti, Michael P; Sotgia, Federica

    2012-11-01

    Here, we identified the milk protein α-casein as a novel suppressor of tumor growth and metastasis. Briefly, Met-1 mammary tumor cells expressing α-casein showed a ~5-fold reduction in tumor growth and a near 10-fold decrease in experimental metastasis. To identify the molecular mechanism(s), we performed genome-wide transcriptional profiling. Interestingly, our results show that α-casein upregulates gene transcripts associated with interferon/STAT1 signaling and downregulates genes associated with "stemness." These findings were validated by immunoblot and FACS analysis, which showed the upregulation and hyperactivation of STAT1 and a decrease in the number of CD44(+) "cancer stem cells." These gene signatures were also able to predict clinical outcome in human breast cancer patients. Thus, we conclude that a lactation-based therapeutic strategy using recombinant α-casein would provide a more natural and non-toxic approach to the development of novel anticancer therapies.

  20. A preparation of cow's late colostrum fraction containing αs1-casein promoted the proliferation of cultured rat intestinal IEC-6 epithelial cells.

    Science.gov (United States)

    Cairangzhuoma; Yamamoto, Mayumi; Xijier; Inagaki, Mizuho; Uchida, Kenji; Yamashita, Kousaku; Saito, Shouichiro; Yabe, Tomio; Kanamaru, Yoshihiro

    2013-01-01

    Colostrum is a complex mixture of bioactives that promotes neonate growth. Recently, we have found by in vivo study that skimmed, sterilized, and concentrated bovine late colostrum (SCBLC), obtained from a Holstein herd on days 6-7 after parturition, had an ability to maintain intestinal integrity. In the present study we investigated effects of SCBLC on rat intestinal IEC-6 cell proliferation in vitro. A fraction containing αs1-casein was found to have a robust stimulation effect as compared to other protein fractions from SCBLC and even the αs1-casein fraction from milk from other Holstein herds. Furthermore, the SCBLC αs1-casein molecule demonstrated not only slightly slower mobility on both SDS- and native-PAGE than other bovine milk αs1-caseins, but also a peculiar conformation reminiscent of moltenglobule in the circular dichroism spectrum. These findings may be of relevant to the competence of SCBLC to preserve intestinal integrity.

  1. Nitrogen balance in lambs fed low-quality brome hay and infused with differing proportions of casein in the rumen and abomasum.

    Science.gov (United States)

    Swanson, K C; Freetly, H C; Ferrell, C L

    2004-02-01

    Twenty wether lambs (46 +/- 2 kg) fitted with ruminal and abomasal infusion catheters were used in a completely randomized design to determine the effects of differing proportions of ruminal and abomasal casein infusion on N balance in lambs fed low-quality brome hay (0.8% N, DM basis) for ad libitum intake. Wethers were infused with 0 (control) or 10.7 g/d of N from casein with ratios of ruminal:abomasal infusion of 100:0 (100R:0A), 67:33 (67R:33A), 33:67 (33R:67A), or 0:100% (0R:100A), respectively, over a 12-d period. Total N supply (hay N intake + N from casein infusion) was greater (P = 0.001) in lambs receiving casein infusion than in controls. Urinary N excretion (g/d) was greater (P = 0.001) in lambs receiving casein infusion than in controls. Urinary N excretion decreased as casein infusion was shifted from 100R:0A to 33R:67A and then slightly increased in lambs receiving 0R:100A (quadratic, P = 0.02). Total N excretion was greater (P = 0.001) in lambs receiving casein infusion than in controls and decreased linearly (P = 0.005) as casein infusion was shifted to the abomasum. Retained N (g/d, % of N intake, and % of digested N) was greater (P = 0.001) in lambs receiving casein than in controls. Retained N increased as infusion was shifted from 100R:0A to 33R:67A and then slightly decreased in lambs receiving 0R: 100A (quadratic, P infusion to maximize N retention was 68% into the abomasum. The regression suggests that supplementation with undegradable intake protein had an additional benefit over supplementation with ruminally degradable intake protein (100R:0A) and that changing the percentage of ruminally undegradable intake protein in supplemental protein from 33 to 100% resulted in minimal differences in N retention. Apparent N, DM, OM, and energy digestibility (% of intake) was greater (P infused with casein than controls but did not differ among casein infusion groups. These data suggest that feeding protein supplements containing a portion (greater

  2. Proving the adulteration of ewe and goat cheeses with cow milk using the reference method of isoelectric focusing of γ-casein

    Directory of Open Access Journals (Sweden)

    Nataša Mikulec

    2013-08-01

    Full Text Available The aim of this study was to introduce a reference method for the detection of cow milk in ewe and goat cheeses (EC 273/08 in order to protect manufacturers and consumers from adulterations and imitations, and to ensure alignment with the demands of domestic and EU markets. The method includes isolation of casein from cheese, isoelectric focusing of γ2- and γ3-casein originating from the hydrolysis of β-casein by plasmin, the detection and quantitative determination of γ-casein in cow, ewe and goat cheese by densitometry. Ewe or goat cheese products with a minimum of 1 % of cow milk are considered to be adulterated. For the quantitative determination of cow, ewe and goat milk in cheeses, standard mixtures of cow-ewe and cow-goat milk were made by adding 0; 0.5; 1; 2; 5; 10; 25; 50; 75 and 100 % (v/v of cow milk. The quantification was performed by determining the peak area ratio of cow γ-casein in comparison to ewe/goat casein in prepared standard cheeses. The calibration curves were calculated based on the relation of the peak area ratio of cow γ-caseins (calculated as the percentage of total γ-caseins in contrast to the relative content (% of cow milk in the mixture. The method proved to be adequate for the detection of raw and heat-treated cow milk in fresh and ripened cheeses made from ewe or goat milk, or a mixture of ewe and goat milk.

  3. 牛αS1-酪蛋白基因研究新进展%The Study Progress of Alpha-s1-casein Gene

    Institute of Scientific and Technical Information of China (English)

    田青

    2011-01-01

    Casein is the main component of milk protein,accounts for about 70~80 percent of total protein.as1-casein is the main component of casein,accounting for about 39~46 percent of total milk protein.It is one of the quite active functional genes in the cattle's mammary gland tissue,so it is important and very necessary to study the cow alpha S1-casein gene.The paper summarized the gene structure,genetic diversity and casein active peptide of alpha-s1-casein gene,which would provide the theory basis to study alpha-s1-casein gene deeply and to improve the milk protein content by regulating as1-casein gene.%酪蛋白是牛奶蛋白质的主要组成部分,约占总蛋白的70%~80%,而as1-酪蛋白又是酪蛋白的主要组成部分,约占牛奶总蛋白的39%~46%,是牛乳腺组织中转录相当活跃的一个功能基因,因此研究牛αS1-酪蛋白基因就显得尤为重要而且很有必要。本文从牛as1-酪蛋白基因结构、遗传多态性和酪蛋白活性肽方面做了综述,旨在为以后牛as1-酪蛋白基因的深入研究和通过调控as1-酪蛋白基因而提高牛奶蛋白质的含量提供理论基础。

  4. Study on the heat stability of caprine casein%羊奶酪蛋白热稳定性的研究

    Institute of Scientific and Technical Information of China (English)

    张富新; 魏怡

    2011-01-01

    Using Saanen & Guanzhong goat milk as material,caprine casein was obtained from the milk. The effects of pH,temperature,ionic calcium,citrate,phosphate and casein on the heat stability of caprine casein were studied by hot coagulation time (HCT). The results showed that the heat stability of casein was better at the pH of 6.8, high temperature can lower the heat stability,ionic calcium can speed up the HCT of casein. A certain amount of citrate or phosphate can effectively raise the hot stability of caprine casein. The addition of casein was not obvious to the heat stability of caprine casein.%以莎能和关中羊奶为原料,通过从羊奶中提取酪蛋白,分别在不同的pH、温度以及添加不同浓度的Ca^2+、柠檬酸钠、三聚磷酸钠、干酪素的条件下测定酪蛋白的热凝固时间(HCT),研究其对羊奶酪蛋白热稳定性的影响。结果表明,pH在6.8时酪蛋白的热稳定性最好,高温会降低酪蛋白的热稳定性,钙离子可以降低羊奶酪蛋白的热稳定性,适量的柠檬酸钠或三聚磷酸钠可以有效提高羊奶酪蛋白的热稳定性,干酪素对酪蛋白稳定性影响不明显。

  5. $\\beta$-Caseinophosphopeptide (f1-25) confers on $\\beta$-casein tryptic hydrolysate an antioxidant activity during iron/ascorbate-induced oxidation of liposomes

    OpenAIRE

    2004-01-01

    International audience; Protein ingredients such as hydrolysates of milk proteins may improve the nutritive value of functional foods. For instance, $\\beta$-casein tryptic hydrolysate could simultaneously increase iron absorption and prevent lipid oxidation in foods containing high contents of polyunsaturated fatty acids (PUFA). The aim of this study was to determine the antioxidant activity of $\\beta$-casein tryptic hydrolysate and of its $\\beta$-caseinophosphopeptide (f1-25) on Fe(III)/asco...

  6. αS1-casein in goat milk: identification of genetic variants by Capillary Zone Electrophoresis compared to Isoelectric Focusing

    Directory of Open Access Journals (Sweden)

    G. Enne

    2011-03-01

    Full Text Available AlphaS1 casein fraction in caprine milk is characterized by an important polymorphism due to substitution, deletion of amino acids and post trascriptional modifications (Grosclaude et al., 1994; Ferranti et al., 1997. This structural polymorphism is associated to a quantitative variability in protein expression related to different milk quality and dairy properties (Pierre et al., 1998; Remeuf, 1993; Vassal et al., 1994. Classical electrophoretic methods were applied to characterize the phenotypic variants at αS1-casein fraction (Addeo et al., 1988; Russo et al., 1986. During the last ten years capillary electrophoresis became an analytical technique for rapid and automated analysis requiring small sample volume and small solvent waste. These characteristics, together with the high resolution and the chance to give quantitative results, made this technique a useful tool........

  7. Effects of casein, whey and soy proteins on volumetric bone density and bone strength in immunocompromised piglets

    DEFF Research Database (Denmark)

    Budek, Alicja Zofia; Bjørnvad, Charlotte; Mølgaard, Christian

    2007-01-01

    Summary:Background and aims: Bone-promoting effect of different proteins in early life, under immunocompromised conditions, is unknown. We investigated effects of milk- and plantderived proteins on bone development in immunocompromised piglets. Methods: Newborn, colostrum-deprived piglets were...... assigned to a formula based on either casein (n=11), whey (n=11) or soy (n=10) as the protein source (each 55 g/L), and equal amounts of fat, carbohydrates, calcium and phosphorus. Results & Conclusion: Despite efforts to sustain immuno-protection (sow serum and antibiotic injections), some piglets became...... sick and were early euthanised. After 6 days, bone density (peripheral quantitative computed tomography), bone mechanical strength (three-point bending test) and serum insulin-like growth factor-I (sIGF-I) (immunoassay) were measured in the surviving piglets (casein n=5, whey n=9, soy n=5)....

  8. Thermal protection of β-carotene in re-assembled casein micelles during different processing technologies applied in food industry.

    Science.gov (United States)

    Sáiz-Abajo, María-José; González-Ferrero, Carolina; Moreno-Ruiz, Ana; Romo-Hualde, Ana; González-Navarro, Carlos J

    2013-06-01

    β-Carotene is a carotenoid usually applied in the food industry as a precursor of vitamin A or as a colourant. β-Carotene is a labile compound easily degraded by light, heat and oxygen. Casein micelles were used as nanostructures to encapsulate, stabilise and protect β-carotene from degradation during processing in the food industry. Self-assembly method was applied to re-assemble nanomicelles containing β-carotene. The protective effect of the nanostructures against degradation during the most common industrial treatments (sterilisation, pasteurisation, high hydrostatic pressure and baking) was proven. Casein micelles protected β-carotene from degradation during heat stabilisation, high pressure processing and the processes most commonly used in the food industry including baking. This opens new possibilities for introducing thermolabile ingredients in bakery products.

  9. Casein and soya-bean protein have different effects on whole body protein turnover at the same nitrogen balance

    DEFF Research Database (Denmark)

    Nielsen, K; Kondrup, J; Elsner, Petteri

    1994-01-01

    was recovered from urinary ammonia and urea during isotope steady state for measurement of protein synthesis and protein degradation. Compared with starvation the protein-free diet decreased N excretion by 75%, probably by increasing the rate of reutilization of amino acids from endogenous proteins for protein...... synthesis. The protein diets produced a positive N balance which was independent of the protein source. Intact and hydrolysed casein increased protein synthesis 2.6- and 2.0-fold respectively, compared with the protein-free diet. Protein degradation increased 1.4- and 1.2-fold respectively. Hydrolysed soya......-bean protein did not increase protein synthesis but decreased protein degradation by 35% compared with the protein-free diet. Compared with the hydrolysed soya-bean protein, intact casein resulted in 2.2- and 2.8-fold higher rates of protein synthesis and degradation respectively. These results are not easily...

  10. Crosslinking with transglutaminase does not change metabolic effects of sodium caseinate in model beverage in healthy young individuals

    Directory of Open Access Journals (Sweden)

    Juvonen Kristiina R

    2012-06-01

    Full Text Available Abstract Background Postprandial metabolic and appetitive responses of proteins are dependent on protein source and processing technique prior to ingestion. Studies on the postprandial effects of enzymatic crosslinking of milk proteins are sparse. Our aim was to study the effect of transglutaminase (TG-induced crosslinking of sodium caseinate on postprandial metabolic and appetite responses. Whey protein was included as reference protein. Methods Thirteen healthy individuals (23.3 ± 1.1 y, BMI 21.7 ± 0.4 kg/m2 participated in a single-blind crossover design experiment in which the subjects consumed three different isovolumic (500 g pourable beverages containing either sodium caseinate (Cas, 29 g, TG-treated sodium caseinate (Cas-TG, 29 g or whey protein (Wh, 30 g in a randomized order. Blood samples were collected at baseline and for 4 h postprandially for the determination of plasma glucose, insulin and amino acid (AA concentrations. Gastric emptying (GE was measured using the 13 C-breath test method. Appetite was assessed using visual analogue scales. Results All examined postprandial responses were comparable with Cas and Cas-TG. The protein type used in the beverages was reflected as differences in plasma AA concentrations between Wh and Cas, but there were no differences in plasma glucose or insulin responses. A tendency for faster GE rate after Wh was detected. Appetite ratings or subsequent energy intake did not differ among the protein beverages. Conclusions Our results indicate that the metabolic responses of enzymatically crosslinked and native sodium caseinate in a liquid matrix are comparable, suggesting similar digestion and absorption rates and first pass metabolism despite the structural modification of Cas-TG.

  11. Prolactin-like activity of anti-prolactin receptor antibodies on casein and DNA synthesis in the mammary gland.

    OpenAIRE

    Djiane, J; Houdebine, L M; Kelly, P A

    1981-01-01

    Prolactin receptors were partially purified from rabbit mammary gland membranes by using an affinity chromatography technique. Antibodies against this prolactin receptor preparation were obtained in guinea pig and sheep. Both antisera were able to inhibit the binding of 125I-labeled ovine prolactin to rabbit mammary gland membranes. When added to culture media of rabbit mammary explants, the anti-prolactin receptor antiserum inhibited the capacity of prolactin to initiate casein synthesis and...

  12. The Effect of Β-casein Nanoparticles on Bioavailability and Cellular Uptake of Platinum Complex as a Cancer Drug

    Directory of Open Access Journals (Sweden)

    M Razmi

    2013-12-01

    Full Text Available Abstract Background & aim: Due to the low solubility and high toxicity of drugs, treatment of cancers is problematic therefore, the encapsulation and targeted delivery of therapeutic effect is required. The aim of this study was to investigate the effect of nanoparticles on cellular uptake and bioavailability of beta-casein on platinum complexes as cancer drugs. Methods: In the present experimental study, the physicochemical properties of nanoparticles as drug carriers of beta-casein devices using dynamic light scattering (DLS and scanning electron microscopy (SEM were investigated. In order to evaluate the toxicity effects of platinum complexes, the colon cancer cells in the absence or presence of free platinum complex concentration and nanoparticle loaded with platinum complexes were incubated for 24 and 48 hours. LD50 Values (concentration of compound causing 50% mortality in the cells was determined using the MTT assay. Data were analyzed by ANOVA and post-hoc test. Results: At a concentration of 1 mg ml, beta-casein nanoparticle drug carriers were synthesized in the range of 100 to 300 µM. In addition, the mortality rate in cancer cells by the release of platinum complexes (without and with the capsule, were 70 and 26 in 24 hours, and 60 µM and 21 µM in 48 hours respectively, Conclusion: The study showed that the bioavailability of the encapsulated platinum complexes increases and new drug delivery system may be a good candidate for the treatment of cancer. Key words: Beta-casein, Pt (II Complex, Bioavalibility, Nanocarrier, Micelle

  13. Preparation of (+)-1-Phenylethylamine by Optical Resolution of Racemic 1-Phenylethylamine with a Chiral Biopolymer,Casein

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    1 Results It has been reported that crystalline form racemates can be resoluted by various methods[1],but for optical resolution of liquid form racemates,the method is limited in chromatograph.So chiral compounds cannot be obtained on large scale by such method.In our previous paper,(+)-3-chloro-1,2-propanediol has been obtained by optical resolution of its racemata (liquid) with a chiral biopolymer,casein[2].

  14. The Gluten-Free/Casein-Free Diet: A Double-Blind Challenge Trial in Children with Autism

    Science.gov (United States)

    Hyman, Susan L.; Stewart, Patricia A.; Foley, Jennifer; Cain, Usa; Peck, Robin; Morris, Danielle D.; Wang, Hongyue; Smith, Tristram

    2016-01-01

    To obtain information on the safety and efficacy of the gluten-free/casein-free (GFCF) diet, we placed 14 children with autism, age 3-5 years, on the diet for 4-6 weeks and then conducted a double-blind, placebo-controlled challenge study for 12 weeks while continuing the diet, with a 12-week follow-up. Dietary challenges were delivered via weekly…

  15. Production efficiency of micellar casein concentrate using polymeric spiral-wound microfiltration membranes.

    Science.gov (United States)

    Beckman, S L; Zulewska, J; Newbold, M; Barbano, D M

    2010-10-01

    Most current research has focused on using ceramic microfiltration (MF) membranes for micellar casein concentrate production, but little research has focused on the use of polymeric spiral-wound (SW) MF membranes. A method for the production of a serum protein (SP)-reduced micellar casein concentrate using SW MF was compared with a ceramic MF membrane. Pasteurized (79°C, 18s) skim milk (1,100 kg) was microfiltered at 50°C [about 3 × concentration] using a 0.3-μm polyvinylidene fluoride spiral-wound membrane, bleed-and-feed, 3-stage process, using 2 diafiltration stages, where the retentate was diluted 1:2 with reverse osmosis water. Skim milk, permeate, and retentate were analyzed for SP content, and the reduction of SP from skim milk was determined. Theoretically, 68% of the SP content of skim milk can be removed using a single-stage 3× MF. If 2 subsequent water diafiltration stages are used, an additional 22% and 7% of the SP can be removed, respectively, giving a total SP removal of 97%. Removal of SP greater than 95% has been achieved using a 0.1-μm pore size ceramic uniform transmembrane pressure (UTP) MF membrane after a 3-stage MF with diafiltration process. One stage of MF plus 2 stages of diafiltration of 50°C skim milk using a polyvinylidene fluoride polymeric SW 0.3-μm membrane yielded a total SP reduction of only 70.3% (stages 1, 2, and 3: 38.6, 20.8, and 10.9%, respectively). The SP removal rate for the polymeric SW MF membrane was lower in all 3 stages of processing (stages 1, 2, and 3: 0.05, 0.04, and 0.03 kg/m(2) per hour, respectively) than that of the comparable ceramic UTP MF membrane (stages 1, 2, and 3: 0.30, 0.11, and 0.06 kg/m(2) per hour, respectively), indicating that SW MF is less efficient at removing SP from 50°C skim milk than the ceramic UTP system. To estimate the number of steps required for the SW system to reach 95% SP removal, the third-stage SP removal rate (27.4% of the starting material SP content) was used to

  16. Gluten-free and casein-free diets in the treatment of autism

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    Andreas Reissmann

    2014-08-01

    Full Text Available Background: Autism is a complex psychiatric disorder characterized by three core symptoms, i.e. impairments in social interaction, restricted patterns of behavior and impairments in communication. In the framework of the “opioid excess theory”, the disorder symptoms are compared to the behavioral effects of opiates. Based on this, a possible nutritional basis of autism has been proposed, hypothesizing that certain food proteins such as gluten and casein can be transformed to opioid peptides during digestion. These peptides might eventually be able to enter the blood stream and act upon the central nervous system. As a consequence, a diet low in such proteins has been hypothesized to ameliorate the behavioral symptoms of autistic children. Objective: The scope of this review was to analyze the effects of gluten-free and casein-free (GFCF diets on children with autism, as well as to provide information concerning additional aspects related to the GFCF diet in autism. Methods: A literature search was conducted including scientific publications up until December 2013. Search results were screened for any kind of GFCF dietary intervention as well as surveys dealing with GFCF as a treatment for autism. Results: A review of survey data shows that up to 25 % of parents of affected children report on current use of a GFCF diet. The majority of identified studies evaluating GFCF diet outcomes failed to meet basic methodological standards of interventional science. Comparison of study results did not show any clear-cut results, with a substantial proportion of studies failing to show any positive dietary effect. The results of more sophisticated trials were far from equivocal and the studies differed by many methodological aspects. Some variables such as information source and trial duration seemed to affect outcome. Conclusions: Evidence for the effectiveness of the GFCF diet in the treatment of autism is sparse. Rigorous scientific evaluations partly

  17. A review of gluten- and casein-free diets for treatment of autism: 2005–2015

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    Elder JH

    2015-12-01

    Full Text Available Jennifer Harrison Elder,1 Consuelo Maun Kreider,2 Nancy M Schaefer,3 Mary B de Laosa4 1Department of Family and Community Health Nursing Science, 2Department of Occupational Therapy, 3Health Science Center Library, 4Department of Psychology, University of Florida, Gainesville, FL, USA Background: The gluten-free, casein-free (GFCF diet is heralded by strong anecdotal parental reports to greatly improve and even "cure" symptoms of autism spectrum disorders (ASDs. Yet, to date, little conclusive empirical evidence exists supporting its use. Objective: The purpose of this paper is to provide an overview of the state of the recent evidence regarding the use of GFCF diet for treatment of individuals with ASD. Methods: Five database providers (PubMed, Web of Knowledge, EBSCO, ProQuest, and WorldCat were used to search 19 databases, yielding a total of 491 articles that were published through February 2015. Peer-reviewed articles published between January 2005 and February 2015 were included for review if study participants were identified as having ASD and if the study investigated the effects of the GFCF diet on ASD behaviors or the relationship between the diet and these behaviors. Results: Evaluation of search results yielded eleven reviews, seven group experimental studies including five randomized controlled trials, five case reports, and four group observational studies published during the last 10 years. These studies represent a marked increase in the number of reported studies as well as increased scientific rigor in investigation of GFCF diets in ASD. Conclusion: While strong empirical support for the GFCF diet in ASD is currently lacking, studies point to the need for identifying subsets of individuals (eg, those with documented gastrointestinal abnormalities who may be the best responders to the GFCF diet. Identifying these subsets is critically needed to enhance rigor in this research area. Until rigorous research supporting the use of

  18. Single nucleotide polymorphisms in the ovine casein genes detected by polymerase chain reaction-single strand conformation polymorphism.

    Science.gov (United States)

    Ceriotti, G; Chessa, S; Bolla, P; Budelli, E; Bianchi, L; Duranti, E; Caroli, A

    2004-08-01

    Casein genetic polymorphisms are important and well known due to their effects on quantitative traits and technological properties of milk. At the DNA level, polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) allows for the simultaneous typing of several alleles at casein loci, as well as the detection of unknown polymorphisms. Here we describe the usefulness of the PCR-SSCP technique for casein typing in sheep. In particular, three single-nucleotide polymorphisms (SNP) are described at CSN1S1, CSN2, and CSN3, all resulting in amino acid exchanges. At CSN1S1, a transition T-->C was found, resulting in the deduced amino acid exchange Ile186-->Thr186. A transition A-->G resulting in the deduced amino acid exchange Met183-->Val183 was identified at CSN2. The 2 SNP showed a rather high frequency (ranging from 0.12 to 0.26) in 3 Italian breeds (Sarda, Comisana, Sopravissana). Another transition C-->T (Ser104-->Leu104) was found at CSN3 in one heterozygous animal.

  19. GENETIC POLYMORPHISM AT THE K-CASEIN LOCUS IN A DAIRY HERD OF ROMANIAN SPOTTED AND BROWN OF MARAMURES BREEDS

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    DANIELA ILIE

    2013-12-01

    Full Text Available Caseins are a family of milk proteins that exist in several molecular forms and arethe main proteins present in the bovine milk. Genetic variation of these proteins hasbeen associated with the quality and quantity of cheese derived from milk.This study was focused on possibilities to evaluate the frequency of the K-casein Ballele in dairy herds from the Research and Development Station for Bovine RaisingArad in order to have breeding programs that target an increase in the frequency ofthe B allele in the dairy cattle population.In order to differentiate the favorable genotype for superior composition and highercheese yield, we used simple DNA extraction method from fresh blood andtechniques based on DNA analysis, which include polymerase chain reaction andrestriction fragment length polymorphisms (PCR-RFLP methods. Employing thesetechniques we were able to determine the k-casein genotype of all individuals in agiven population under selection, regardless of sex, age or physiological stage.As a result, it is now possible to include information on milk protein genotypes intomarker assisted selection programs and consequently improve response to selection.

  20. Effects of dairy factory, milk casein content and titratable acidity on coagulation properties in Trentingrana dairy industry.

    Science.gov (United States)

    Penasa, Mauro; Toffanin, Valentina; Cologna, Nicola; Cassandro, Martino; De Marchi, Massimo

    2016-05-01

    The objective of the present study was to investigate the effect of environmental factors, milk casein content and titratable acidity on milk coagulation properties (MCP) of samples routinely collected in the Trento province (northeast Italy) under field conditions. Rennet coagulation time (RCT, min), curd-firming time (k20, min) and curd firmness (a30, mm) were determined by Formagraph on 14 971 samples from 635 herds associated to 17 dairy factories. Besides MCP, fat, protein, and casein percentages, titratable acidity (TA), and somatic cell and bacterial counts were available. A standardised index of milk aptitude to coagulate (IAC) was derived using information of RCT and a30. An analysis of variance was conducted on MCP and IAC using a fixed effects linear model. Approximately 3% of milk samples did not form a curd within the testing time (30 min) and k20 was missing for 26% of milks. The percentage of samples without information on k20 largely differed among dairy factories (1·7-20·9%). Significant differences were estimated between the best and the worst dairy factory for RCT (-2 min), k20 (-1·2 min), a30 (+3·4 mm) and IAC (+2·6 points). Milk casein content and TA were important factors in explaining the variation of MCP and IAC, supporting the central role of these two traits on technological properties. The Trento province is heterogeneous in terms of dairy systems and this could explain the differences among dairy factories.

  1. Microstructural, textural, and sensory characteristics of probiotic yogurts fortified with sodium calcium caseinate or whey protein concentrate.

    Science.gov (United States)

    Akalın, A S; Unal, G; Dinkci, N; Hayaloglu, A A

    2012-07-01

    The influence of milk protein-based ingredients on the textural characteristics, sensory properties, and microstructure of probiotic yogurt during a refrigerated storage period of 28 d was studied. Milk was fortified with 2% (wt/vol) skim milk powder as control, 2% (wt/vol) sodium calcium caseinate (SCaCN), 2% (wt/vol) whey protein concentrate (WPC) or a blend of 1% (wt/vol) SCaCN and 1% (wt/vol) WPC. A commercial yogurt starter culture and Bifidobacterium lactis Bb12 as probiotic bacteria were used for the production. The fortification with SCaCN improved the firmness and adhesiveness. Higher values of viscosity were also obtained in probiotic yogurts with SCaCN during storage. However, WPC enhanced water-holding capacity more than the caseinate. Addition of SCaCN resulted in a coarse, smooth, and more compact protein network; however, WPC gave finer and bunched structures in the scanning electron microscopy micrographs. The use of SCaCN decreased texture scores in probiotic yogurt; probably due to the lower water-holding capacity and higher syneresis values in the caseinate-added yogurt sample. Therefore, the textural characteristics of probiotic yogurts improved depending on the ingredient variety.

  2. Effect of high pressure--low temperature treatments on structural characteristics of whey proteins and micellar caseins.

    Science.gov (United States)

    Baier, Daniel; Purschke, Benedict; Schmitt, Christophe; Rawel, Harshadrai M; Knorr, Dietrich

    2015-11-15

    In this study, structural changes in micellar caseins and whey proteins due to high pressure--low temperature treatments (HPLT) were investigated and compared to changes caused by high pressure treatments at room temperature. Whey protein isolate (WPI) solutions as well as micellar casein (MC) dispersions and mixtures were treated at 500 MPa (pH 7.0 and 5.8) at room temperature, -15 °C and -35 °C. Surface hydrophobicity and accessible thiol groups remained nearly unchanged after HPLT treatments whereas HP treatments at room temperature caused an unfolding of the WPI, resulting in an increase in surface hydrophobicity and exposure of the thiol groups. For HPLT treatments, distinct changes in the secondary structure (increase in the amount of β-sheets) were observed while the tertiary structure remained unchanged. Large flocs, stabilized by hydrophobic interactions and hydrogen bonds, were formed in casein containing samples due to HPLT treatments. Depending on the pH and the applied HPLT treatment parameters, these interactions differed significantly from the interactions determined in native micelles.

  3. GENETIC POLYMORPHISM AT THE K-CASEIN LOCUS IN A DAIRY HERD OF ROMANIAN SPOTTED AND BROWN OF MARAMURES BREEDS

    Directory of Open Access Journals (Sweden)

    ILIE DANIELA

    2007-01-01

    Full Text Available Caseins are a family of milk proteins that exist in several molecular forms and arethe main proteins present in the bovine milk. Genetic variation of these proteins hasbeen associated with the quality and quantity of cheese derived from milk.This study was focused on possibilities to evaluate the frequency of the K-casein Ballele in dairy herds from the Research and Development Station for Bovine RaisingArad in order to have breeding programs that target an increase in the frequency ofthe B allele in the dairy cattle population.In order to differentiate the favorable genotype for superior composition and highercheese yield, we used simple DNA extraction method from fresh blood andtechniques based on DNA analysis, which include polymerase chain reaction andrestriction fragment length polymorphisms (PCR-RFLP methods. Employing thesetechniques we were able to determine the k-casein genotype of all individuals in agiven population under selection, regardless of sex, age or physiological stage.As a result, it is now possible to include information on milk protein genotypes intomarker assisted selection programs and consequently improve response to selection.

  4. Diffusion and partitioning of macromolecules in casein microgels: evidence for size-dependent attractive interactions in a dense protein system.

    Science.gov (United States)

    Peixoto, Paulo D S; Bouchoux, Antoine; Huet, Sébastien; Madec, Marie-Noëlle; Thomas, Daniel; Floury, Juliane; Gésan-Guiziou, Geneviève

    2015-02-10

    Understanding the mechanisms that determine the diffusion and interaction of macromolecules (such as proteins and polysaccharides) that disperse through dense media is an important fundamental issue in the development of innovative technological and medical applications. In the current work, the partitioning and diffusion of macromolecules of different sizes (from 4 to 10 nm in diameter) and shapes (linear or spherical) within dispersions of casein micelles (a protein microgel) is studied. The coefficients for diffusion and partition are measured using FRAP (fluorescence recovery after photobleaching) and analyzed with respect to the structural characteristics of the microgel determined by the use of TEM (transmission electron microscopy) tomography. The results show that the casein microgel displays a nonspecific attractive interaction for all macromolecules studied. When the macromolecular probes are spherical, this affinity is clearly size-dependent, with stronger attraction for the larger probes. The current data show that electrostatic effects cannot account for such an attraction. Rather, nonspecific hydration molecular forces appear to explain these results. These findings show how weak nonspecific forces affect the diffusion and partitioning of proteins and polysaccharides in a dense protein environment. These results could be useful to better understand the mechanisms of diffusion and partitioning in other media such as cells and tissues. Furthermore, there arises the possibility of using the casein micelle as a size-selective molecular device.

  5. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion related to a notification from the International Organisation of Vine and Wine (OIV) on casein/caseinate/milk products to be used in the manufacture of wine as clarification processing aids pursuant to Article 6

    DEFF Research Database (Denmark)

    Tetens, Inge

    of wine as clarification processing aids pursuant to Article 6, paragraph 11 of Directive 2000/13/EC – for permanent exemption from labelling. In earlier assessments, the Panel concluded that wines fined with casein/caseinate/milk products may trigger adverse reactions in susceptible individuals under...... refers to new analytical methods developed for the detection of milk allergens in the fining agent and the detection of casein in wine. There were no changes in the wine manufacturing process and no new clinical studies were provided. Taking into account the information provided on the characterisation...

  6. Active Bilayer PE/PCL Films for Food Packaging Modified with Zinc Oxide and Casein

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    Ana Rešček

    2015-12-01

    Full Text Available This paper studies the properties of active polymer food packaging bilayer polyethylene/polycaprolactone (PE/PCL films. Such packaging material consists of primary PE layer coated with thin film of PCL coating modified with active component (zinc oxide or zinc oxide/casein complex with intention to extend the shelf life of food and to maintain the quality and health safety. The influence of additives as active components on barrier, mechanical, thermal and antimicrobial properties of such materials was studied. The results show that, in comparison to the neat PE and PE/PCL films, some of PE/PCL bilayer films with additives exhibit improved barrier properties i.e. decreased water vapour permeability. Higher thermal stability of modified PE/PCL material is obtained due to a modified mechanism of thermal degradation. The samples with the additive nanoparticles homogeneously dispersed in the polymer matrix showed good mechanical properties. Addition of higher ZnO content contributes to the enhanced antibacterial activity of a material.

  7. Functional analysis of Casein Kinase 1 in a minimal circadian system.

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    Gerben van Ooijen

    Full Text Available The Earth's rotation has driven the evolution of cellular circadian clocks to facilitate anticipation of the solar cycle. Some evidence for timekeeping mechanism conserved from early unicellular life through to modern organisms was recently identified, but the components of this oscillator are currently unknown. Although very few clock components appear to be shared across higher species, Casein Kinase 1 (CK1 is known to affect timekeeping across metazoans and fungi, but has not previously been implicated in the circadian clock in the plant kingdom. We now show that modulation of CK1 function lengthens circadian rhythms in Ostreococcustauri, a unicellular marine algal species at the base of the green lineage, separated from humans by ~1.5 billion years of evolution. CK1 contributes to timekeeping in a phase-dependent manner, indicating clock-mediated gating of CK1 activity. Label-free proteomic analyses upon overexpression as well as inhibition revealed CK1-responsive phosphorylation events on a set of target proteins, including highly conserved potentially clock-relevant cellular regulator proteins. These results have major implications for our understanding of cellular timekeeping and can inform future studies in any circadian organism.

  8. SOYBEAN AND CASEIN HYDROLYSATES INDUCE GRAPEVINE IMMUNE RESPONSES AND RESISTANCE AGAINST PLASMOPARA VITICOLA

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    Nihed eLachhab

    2014-12-01

    Full Text Available Plasmopara viticola, the causal agent of grapevine downy mildew, is one of the most devastating grape pathogen in Europe and North America. Although phytochemicals are used to control pathogen infections, the appearance of resistant strains and the concern for possible adverse effects on environment and human health are increasing the search for alternative strategies. In the present investigation, we successfully tested two protein hydrolysates from soybean (soy and casein (cas to trigger grapevine resistance against P. viticola. On Vitis vinifera cv. Marselan plants, the application of soy and cas reduced the infected leaf surface by 76 and 63%, as compared to the control, respectively. Since both hydrolysates might trigger the plant immunity, we investigated their ability to elicit grapevine defence responses. On grapevine cell suspensions, a different free cytosolic calcium signature was recorded for each hydrolysate, whereas a similar transient phosphorylation of two MAP kinases of 45 and 49 kDa was observed. These signalling events were followed by transcriptome reprogramming, including the up-regulation of defence genes encoding pathogenesis-related (PR proteins and the stilbene synthase enzyme responsible for the biosynthesis of resveratrol, the main grapevine phytoalexin. Liquid chromatography analyses confirmed the production of resveratrol and its dimer metabolites, δ- and ε-viniferins. Overall, soy effects were more pronounced as compared to the cas one. Both hydrolysates proved to act as elicitors to enhance grapevine immunity against pathogen attack.

  9. Microstructural evolution of viscoelastic emulsions stabilised by sodium caseinate and xanthan gum.

    Science.gov (United States)

    Moschakis, Thomas; Murray, Brent S; Dickinson, Eric

    2005-04-15

    The time-dependent evolution of the phase-separated microstructure of a caseinate-stabilised emulsion containing xanthan gum added before emulsification has been investigated by confocal laser scanning microscopy, image analysis and rheology. Moderately low levels of xanthan addition lead to depletion flocculation and gravity-induced phase separation. Increasing the polysaccharide concentration causes immobilisation of the microstructure due to an increase in the local viscoelasticity: that is, the emulsion structure cannot easily rearrange to expel xanthan-enriched aqueous serum phase because a weak gel-like network is generated. The effect of xanthan on the evolving microstructure of phase-separated regions, which reflects indirectly the local emulsion micro-rheology, has been estimated from image analysis of time sequences of confocal micrographs. A comparison has been made between object shape analysis using four different shape descriptors. The roundness parameter has been found to be a convenient descriptor for reliably quantifying the structural change in terms of the relaxation rate of xanthan-rich aqueous drops. The Taylor parameter has been used to link the kinetics of drop relaxation to the time-dependent small-deformation rheological behaviour. The analysis of the combined experimental data reveals the difficulty of relating the evolving microstructure to bulk rheological measurements.

  10. Casein kinase 1 proteomics reveal prohibitin 2 function in molecular clock.

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    Lorna S Kategaya

    Full Text Available Throughout the day, clock proteins synchronize changes in animal physiology (e.g., wakefulness and appetite with external cues (e.g., daylight and food. In vertebrates, both casein kinase 1 delta and epsilon (CK1δ and CK1ε regulate these circadian changes by phosphorylating other core clock proteins. In addition, CK1 can regulate circadian-dependent transcription in a non-catalytic manner, however, the mechanism is unknown. Furthermore, the extent of functional redundancy between these closely related kinases is debated. To further advance knowledge about CK1δ and CK1ε mechanisms of action in the biological clock, we first carried out proteomic analysis of both kinases in human cells. Next, we tested interesting candidates in a cell-based circadian readout which resulted in the discovery of PROHIBITIN 2 (PHB2 as a modulator of period length. Decreasing the expression of PHB2 increases circadian-driven transcription, thus revealing PHB2 acts as an inhibitor in the molecular clock. While stable binding of PHB2 to either kinase was not detected, knocking down CK1ε expression increases PHB2 protein levels and, unexpectedly, knocking down CK1δ decreases PHB2 transcript levels. Thus, isolating CK1 protein complexes led to the identification of PHB2 as an inhibitor of circadian transcription. Furthermore, we show that CK1δ and CK1ε differentially regulate the expression of PHB2.

  11. Casein and soybean protein-based thermoplastics and composites as alternative biodegradable polymers for biomedical applications.

    Science.gov (United States)

    Vaz, C M; Fossen, M; van Tuil, R F; de Graaf, L A; Reis, R L; Cunha, A M

    2003-04-01

    This work reports on the development and characterization of novel meltable polymers and composites based on casein and soybean proteins. The effects of inert (Al(2)O(3)) and bioactive (tricalcium phosphate) ceramic reinforcements over the mechanical performance, water absorption, and bioactivity behavior of the injection-molded thermoplastics were examined. It was possible to obtain materials and composites with a range of mechanical properties, which might allow for their application in the biomedical field. The incorporation of tricalcium phosphate into the soybean thermoplastic decreased its mechanical properties but lead to the nucleation of a bioactive calcium-phosphate film on their surface when immersed in a simulated body fluid solution. When compounded with 1% of a zirconate coupling agent, the nucleation and growth of the bioactive films on the surface of the referred to composites was accelerated. The materials degradation was studied for ageing periods up to 60 days in an isotonic saline solution. Both water uptake and weight loss were monitored as a function of the immersion time. After 1 month of immersion, the materials showed signal of chemical degradation, presenting weight losses up to 30%. However, further improvement on the mechanical performance and the enhancement of the hydrolytic stability of those materials will be highly necessary for applications in the biomedical field.

  12. The endoplasmic reticulum and casein-containing vesicles contribute to milk fat globule membrane.

    Science.gov (United States)

    Honvo-Houéto, Edith; Henry, Céline; Chat, Sophie; Layani, Sarah; Truchet, Sandrine

    2016-10-01

    During lactation, mammary epithelial cells secrete huge amounts of milk from their apical side. The current view is that caseins are secreted by exocytosis, whereas milk fat globules are released by budding, enwrapped by the plasma membrane. Owing to the number and large size of milk fat globules, the membrane surface needed for their release might exceed that of the apical plasma membrane. A large-scale proteomics analysis of both cytoplasmic lipid droplets and secreted milk fat globule membranes was used to decipher the cellular origins of the milk fat globule membrane. Surprisingly, differential analysis of protein profiles of these two organelles strongly suggest that, in addition to the plasma membrane, the endoplasmic reticulum and the secretory vesicles contribute to the milk fat globule membrane. Analysis of membrane-associated and raft microdomain proteins reinforces this possibility and also points to a role for lipid rafts in milk product secretion. Our results provide evidence for a significant contribution of the endoplasmic reticulum to the milk fat globule membrane and a role for SNAREs in membrane dynamics during milk secretion. These novel aspects point to a more complex model for milk secretion than currently envisioned.

  13. Thermally-dried immobilized kefir on casein as starter culture in dried whey cheese production.

    Science.gov (United States)

    Dimitrellou, D; Kourkoutas, Y; Koutinas, A A; Kanellaki, M

    2009-12-01

    The aim of the present study was to evaluate the use of thermally-dried immobilized kefir on casein as a starter culture for protein-enriched dried whey cheese. For comparison reasons, dried whey cheese with thermally-dried free kefir culture and with no starter culture were also produced. The effect of the nature of the culture, the ripening temperature and the ripening process on quality characteristics of the whey cheese was studied. The association of microbial groups during cheese maturation suggested repression of spoilage and protection from pathogens due to the thermally-dried kefir, as counts of coliforms, enterobacteria and staphylococci were significantly reduced in cheeses produced using thermally-dried kefir starter cultures. The effect of the starter culture on production of volatile compounds responsible for cheese flavor was also studied using the SPME GC/MS technique. Thermally-dried immobilized kefir starter culture resulted in an improved profile of aroma-related compounds. The preliminary sensory evaluation ascertained the soft, fine taste and the overall improved quality of cheese produced with the thermally-dried immobilized kefir. The potential of protein-based thermally-dried starter cultures in dairy products is finally highlighted and assessed.

  14. Circadian metabolic regulation through crosstalk between casein kinase 1δ and transcriptional coactivator PGC-1α.

    Science.gov (United States)

    Li, Siming; Chen, Xiao-Wei; Yu, Lei; Saltiel, Alan R; Lin, Jiandie D

    2011-12-01

    Circadian clock coordinates behavior and physiology in mammals in response to light and feeding cycles. Disruption of normal clock function is associated with increased risk for cardiovascular and metabolic diseases, underscoring the emerging concept that temporal regulation of tissue metabolism is a fundamental aspect of energy homeostasis. We have previously demonstrated that transcriptional coactivator, peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), coordinates circadian metabolic rhythms through simultaneous regulation of metabolic and clock gene expression. In this study, we found that PGC-1α physically interacts with, and is phosphorylated by, casein kinase 1δ (CK1δ), a core component of the circadian pacemaker. CK1δ represses the transcriptional function of PGC-1α in cultured hepatocytes, resulting in decreased gluconeogenic gene expression and glucose secretion. At the molecular level, CK1δ phosphorylation of PGC-1α within its arginine/serine-rich domain enhances its degradation through the proteasome system. Together, these results elucidate a novel mechanism through which circadian pacemaker transduces timing signals to the metabolic regulatory network that controls hepatic energy metabolism.

  15. Regulation of Ceramide Synthase by Casein Kinase 2-dependent Phosphorylation in Saccharomyces cerevisiae*

    Science.gov (United States)

    Fresques, Tara; Niles, Brad; Aronova, Sofia; Mogri, Huzefa; Rakhshandehroo, Taha; Powers, Ted

    2015-01-01

    Complex sphingolipids are important components of eukaryotic cell membranes and, together with their biosynthetic precursors, including sphingoid long chain bases and ceramides, have important signaling functions crucial for cell growth and survival. Ceramides are produced at the endoplasmic reticulum (ER) membrane by a multicomponent enzyme complex termed ceramide synthase (CerS). In budding yeast, this complex is composed of two catalytic subunits, Lac1 and Lag1, as well as an essential regulatory subunit, Lip1. Proper formation of ceramides by CerS has been shown previously to require the Cka2 subunit of casein kinase 2 (CK2), a ubiquitous enzyme with multiple cellular functions, but the precise mechanism involved has remained unidentified. Here we present evidence that Lac1 and Lag1 are direct targets for CK2 and that phosphorylation at conserved positions within the C-terminal cytoplasmic domain of each protein is required for optimal CerS activity. Our data suggest that phosphorylation of Lac1 and Lag1 is important for proper localization and distribution of CerS within the ER membrane and that phosphorylation of these sites is functionally linked to the COP I-dependent C-terminal dilysine ER retrieval pathway. Together, our data identify CK2 as an important regulator of sphingolipid metabolism, and additionally, because both ceramides and CK2 have been implicated in the regulation of cancer, our findings may lead to an enhanced understanding of their relationship in health and disease. PMID:25429105

  16. Regulation of ceramide synthase by casein kinase 2-dependent phosphorylation in Saccharomyces cerevisiae.

    Science.gov (United States)

    Fresques, Tara; Niles, Brad; Aronova, Sofia; Mogri, Huzefa; Rakhshandehroo, Taha; Powers, Ted

    2015-01-16

    Complex sphingolipids are important components of eukaryotic cell membranes and, together with their biosynthetic precursors, including sphingoid long chain bases and ceramides, have important signaling functions crucial for cell growth and survival. Ceramides are produced at the endoplasmic reticulum (ER) membrane by a multicomponent enzyme complex termed ceramide synthase (CerS). In budding yeast, this complex is composed of two catalytic subunits, Lac1 and Lag1, as well as an essential regulatory subunit, Lip1. Proper formation of ceramides by CerS has been shown previously to require the Cka2 subunit of casein kinase 2 (CK2), a ubiquitous enzyme with multiple cellular functions, but the precise mechanism involved has remained unidentified. Here we present evidence that Lac1 and Lag1 are direct targets for CK2 and that phosphorylation at conserved positions within the C-terminal cytoplasmic domain of each protein is required for optimal CerS activity. Our data suggest that phosphorylation of Lac1 and Lag1 is important for proper localization and distribution of CerS within the ER membrane and that phosphorylation of these sites is functionally linked to the COP I-dependent C-terminal dilysine ER retrieval pathway. Together, our data identify CK2 as an important regulator of sphingolipid metabolism, and additionally, because both ceramides and CK2 have been implicated in the regulation of cancer, our findings may lead to an enhanced understanding of their relationship in health and disease.

  17. Goat's αS1-casein polymorphism affects gene expression profile of lactating mammary gland.

    Science.gov (United States)

    Ollier, S; Chauvet, S; Martin, P; Chilliard, Y; Leroux, C

    2008-04-01

    Goat's αS1-casein (CSN1S1) polymorphism has a significant effect on milk protein and lipid composition, which affects the nutritional quality and technological properties of milk. Moreover, this polymorphism has a large impact on the morphology of mammary epithelial cells. To explore the metabolic pathways modulated in relation to this polymorphism, we compared the mammary gene expression profiles of two groups of lactating goats carrying either two reference or two defective alleles, using a bovine oligonucleotide microarray representing 8379 genes. We identified 41 differentially expressed genes between the two genotype groups. In particular, we showed a downregulation of two key lipogenic genes encoding fatty acid synthase and glycerol-3-phosphate acyltransferase in agreement with the low fat concentration associated with CSN1S1 deficiency. In addition, this study highlights changes in the expression level of several genes known to influence membrane fluidity, cell-cell interaction or chromatin organization. Our results open up new fields of investigation on structural modifications associated with CSN1S1 deficiency that could affect mammary gland function.

  18. Goat casein genotypes are associated with milk production traits in the Sarda breed.

    Science.gov (United States)

    Vacca, G M; Dettori, M L; Piras, G; Manca, F; Paschino, P; Pazzola, M

    2014-10-01

    The aim of the current work was to analyze, in the Sarda breed goat, genetic polymorphism within the casein genes and to assess their influence on milk traits. Genetic variants at the CSN1S1, CSN2, CSN1S2 and CSN3 gene loci were investigated using PCR-based methods, cloning and sequencing. Strong alleles prevailed at the CSN1S1 gene locus and defective alleles also were revealed. Null alleles were evidenced at each calcium-sensitive gene locus. At the CSN3 gene locus, we observed a prevalence of the CSN3 A and B alleles; the occurrence of rare alleles such as CSN3 B'', C, C', D, E and M; and the CSN3 S allele (GenBank KF644565) described here for the first time in Capra hircus. Statistical analysis showed that all genes, except CSN3, significantly influenced milk traits. The CSN1S1 BB and AB genotypes were associated with the highest percentages of protein (4.41 and 4.40 respectively) and fat (5.26 and 5.34 respectively) (P milk protein content and yield. The polymorphism of the CSN2 gene affected milk protein percentage with the highest values recorded in the CSN2 AA goats (4.35, at P goats provided the highest fat (51.02 g/day) and protein (41.42 g/day) (P goat.

  19. Casein kinase G may be the target of spermine during progesterone-induced oocyte maturation

    Institute of Scientific and Technical Information of China (English)

    LIRUNSHENG; JIAKETSO

    1993-01-01

    Casein kinase G (CKG) with more than 2500-fold enrichraent was purified from Bufo bufo gargarizans ovaries. The catalytic activity of the enzyme was found to be associated with its 42 kD subunit, and its 26 kD subunit was found to be the major tsrget for the enzyme autophos phorylation. Each fuU-grown oocyte contained 1.9 units of CKG corresponding to an intracellular concentration of 93 nM. After injecting an amount of 0,38 units of the enzyme into the oocyte, approximately 50% of the progesterone-induoed maturation was inhibited. The inhibitory effect was enhanced in oocytes pretreated with spermine, which was consistent with the results that the enzyme was activated in vitro in the presence of spermine, The MPF-induced oocyte maturation was delayed and even prohibited in the kinase-microinjected oocytes. A 55 kD oocyte protein was identified as an suhstrate of CKG both in vivo and in vitro, and the enhancement of the 55 kD protein phosphory[ation was associated with kinase inhibition on maturation and on protein synthesis in kinase-microinjected oocytes. As the endogenous spermine level decreased in the course of progesteroneinduced oocyte maturation. 55 kD protein was dephosphorylated, Heparin, a specific inhibitor of CKG, potentiated the progesterone-induced oocyte maturation. Altogether the experimental reSults indicated Strongly that CKG may be the physiological target of spermine.

  20. Regulation of Ikaros function by casein kinase 2 and protein phosphatase 1

    Institute of Scientific and Technical Information of China (English)

    Amy; K; Erbe; Aleksandar; Savic; Sinisa; Dovat

    2011-01-01

    The Ikaros gene encodes a zinc finger,DNA-binding protein that regulates gene transcription and chromatin remodeling.Ikaros is a master regulator of hematopoiesis and an established tumor suppressor.Moderate alteration of Ikaros activity (e.g.haploinsufficiency) appears to be sufficient to promote malignant transformation in human hematopoietic cells.This raises questions about the mechanisms that normally regulate Ikaros function and the potential of these mechanisms to contribute to the development of leukemia.The focus of this review is the regulation of Ikaros function by phosphorylation/dephosphorylation.Site-specific phosphorylation of Ikaros by casein kinase 2 (CK2) controls Ikaros DNA-binding ability and subcellular localization.As a consequence,the ability of Ikaros to regulate cell cycle progression,chromatin remodeling,target gene expression,and thymocyte differentiation are controlled by CK2.In addition,hyperphosphorylation of Ikaros by CK2 leads to decreased Ikaros levels due to ubiquitinmediated degradation.Dephosphorylation of Ikaros by protein phosphatase 1 (PP1) acts in opposition to CK2 to increase Ikaros stability and restore Ikaros DNA binding ability and pericentromeric localization.Thus,the CK2 and PP1 pathways act in concert to regulate Ikaros activity in hematopoiesis and as a tumor suppressor.This highlights the importance of these signal transduction pathways as potential mediators of leukemogenesis via their role in regulating the activities of Ikaros.

  1. Double-antibody based immunoassay for the detection of β-casein in bovine milk samples.

    Science.gov (United States)

    Zhou, Y; Song, F; Li, Y S; Liu, J Q; Lu, S Y; Ren, H L; Liu, Z S; Zhang, Y Y; Yang, L; Li, Z H; Zhang, J H; Wang, X R

    2013-11-01

    The concentration of casein (CN) is one of the most important parameters for measuring the quality of bovine milk. Traditional approach to CN concentration determination is Kjeldahl, which is an indirect method for determination of total nitrogen content. Here, we described a double-antibody based direct immunoassay for the detection of β-CN in bovine milk samples. Monoclonal antibody (McAb) was used as capture antibody and polyclonal antibody (PcAb) labelled with horseradish peroxidase (HRP) as detection antibody. With the direct immunoassay format, the linear range of the detection was 0.1-10.0 μg mL(-1). The detection limit was 0.04 μg mL(-1). In addition, the concentration of β-CN in real bovine milk samples has been detected by the developed immunoassay. There was a good correlation between the results obtained by the developed technique and Kjeldahl method from commercial samples. Compared to the traditional approach, the advantage of the assay is no need of time-consuming sample pretreatment.

  2. Casein Kinase 2 Reverses Tail-Independent Inactivation of Kinesin-1

    Science.gov (United States)

    Xu, Jing; Reddy, Babu J. N.; Anand, Preetha; Shu, Zhanyong; Cermelli, Silvia; Mattson, Michelle K.; Tripathy, Suvranta K.; Hoss, Matthew T.; James, Nikita S.; King, Stephen J.; Huang, Lan; Bardwell, Lee; Gross, Steven P.

    2013-01-01

    Kinesin-1 is a plus-end microtubule-based motor, and defects in kinesin-based transport are linked to diseases including neurodegeneration. Kinesin can auto-inhibit via a head-tail interaction, but is believed to be active otherwise. Here we report a tail-independent inactivation of kinesin, reversible by the disease-relevant signaling protein, casein kinase 2 (CK2). The majority of initially active kinesin (native or tail-less) loses its ability to interact with microtubules in vitro, and CK2 reverses this inactivation (~ 4-fold) without altering kinesin’s single motor properties. This activation pathway does not require motor phosphorylation, and is independent of head-tail auto-inhibition. In cultured mammalian cells, reducing CK2 expression, but not its kinase activity, decreases the force required to stall lipid droplet transport, consistent with a decreased number of active kinesin motors. Our results provide the first direct evidence of a protein kinase up-regulating kinesin-based transport, and suggest a novel pathway for regulating the activity of cargo-bound kinesin. PMID:22453827

  3. Gold nanoparticle aggregation-based colorimetric assay for β-casein detection in bovine milk samples.

    Science.gov (United States)

    Li, Y S; Zhou, Y; Meng, X Y; Zhang, Y Y; Song, F; Lu, S Y; Ren, H L; Hu, P; Liu, Z S; Zhang, J H

    2014-11-01

    Traditional Kjeldahl method, used for quality evaluation of bovine milk, has intrinsic defects of time-consuming sample preparation and two analyses to determine the difference between non-protein nitrogen content and total protein nitrogen content. Herein, based upon antibody functionalized gold nanoparticles (AuNPs), we described a colorimetric method for β-casein (β-CN) detection in bovine milk samples. The linear dynamic range and the LOD were 0.08-250 μg mL(-1), and 0.03 μg mL(-1) respectively. In addition, the real content of β-CN in bovine milk was measured by using the developed assay. The results are closely correlated with those from Kjeldahl method. The advantages of β-CN triggered AuNP aggregation-based colorimetric assay are simple signal generation, the high sensitivity and specificity as well as no need of complicated sample preparation, which make it for on-site detection of β-CN in bovine milk samples.

  4. Novel ionically crosslinked casein nanoparticles for flutamide delivery: formulation, characterization, and in vivo pharmacokinetics.

    Science.gov (United States)

    Elzoghby, Ahmed O; Helmy, Maged W; Samy, Wael M; Elgindy, Nazik A

    2013-01-01

    A novel particulate delivery matrix based on ionically crosslinked casein (CAS) nanoparticles was developed for controlled release of the poorly soluble anticancer drug flutamide (FLT). Nanoparticles were fabricated via oil-in-water emulsification then stabilized by ionic crosslinking of the positively charged CAS molecules below their isoelectric point, with the polyanionic crosslinker sodium tripolyphosphate. With the optimal preparation conditions, the drug loading and incorporation efficiency achieved were 8.73% and 64.55%, respectively. The nanoparticles exhibited a spherical shape with a size below 100 nm and a positive zeta potential (+7.54 to +17.3 mV). FLT was molecularly dispersed inside the nanoparticle protein matrix, as revealed by thermal analysis. The biodegradability of CAS nanoparticles in trypsin solution could be easily modulated by varying the sodium tripolyphosphate crosslinking density. A sustained release of FLT from CAS nanoparticles for up to 4 days was observed, depending on the crosslinking density. After intravenous administration of FLT-CAS nanoparticles into rats, CAS nanoparticles exhibited a longer circulation time and a markedly delayed blood clearance of FLT, with the half-life of FLT extended from 0.88 hours to 14.64 hours, compared with drug cosolvent. The results offer a promising method for tailoring biodegradable, drug-loaded CAS nanoparticles as controlled, long-circulating drug delivery systems of hydrophobic anticancer drugs in aqueous vehicles.

  5. Casein kinase 1 proteomics reveal prohibitin 2 function in molecular clock.

    Science.gov (United States)

    Kategaya, Lorna S; Hilliard, Aisha; Zhang, Louying; Asara, John M; Ptáček, Louis J; Fu, Ying-Hui

    2012-01-01

    Throughout the day, clock proteins synchronize changes in animal physiology (e.g., wakefulness and appetite) with external cues (e.g., daylight and food). In vertebrates, both casein kinase 1 delta and epsilon (CK1δ and CK1ε) regulate these circadian changes by phosphorylating other core clock proteins. In addition, CK1 can regulate circadian-dependent transcription in a non-catalytic manner, however, the mechanism is unknown. Furthermore, the extent of functional redundancy between these closely related kinases is debated. To further advance knowledge about CK1δ and CK1ε mechanisms of action in the biological clock, we first carried out proteomic analysis of both kinases in human cells. Next, we tested interesting candidates in a cell-based circadian readout which resulted in the discovery of PROHIBITIN 2 (PHB2) as a modulator of period length. Decreasing the expression of PHB2 increases circadian-driven transcription, thus revealing PHB2 acts as an inhibitor in the molecular clock. While stable binding of PHB2 to either kinase was not detected, knocking down CK1ε expression increases PHB2 protein levels and, unexpectedly, knocking down CK1δ decreases PHB2 transcript levels. Thus, isolating CK1 protein complexes led to the identification of PHB2 as an inhibitor of circadian transcription. Furthermore, we show that CK1δ and CK1ε differentially regulate the expression of PHB2.

  6. Efficiency of manganese absorption in chicks fed corn-soy and casein diets.

    Science.gov (United States)

    Halpin, K M; Chausow, D G; Baker, D H

    1986-09-01

    Experiments were conducted with young chicks to quantify the absorption efficiency of manganese (Mn) using tibia Mn uptake as the response criterion. Chicks in experiment 1 were fed a corn-soybean meal diet and either injected intraperitoneally or crop intubated twice daily with three levels of inorganic Mn provided as MnSO4 X H2O. After 14 d, chicks were killed, and intact tibias were removed to facilitate calculation of bone Mn concentration. Excellent straight-line fits (bone Mn concentration as a function of Mn administered) allowed estimation of gut absorption efficiency of Mn by slope-ratio methodology. Absorption efficiency of Mn was calculated to be 1.71% for chicks fed the corn-soy diet. Identical methodology was employed in experiment 2 wherein chicks were fed a phytate- and fiber-free casein-dextrose diet. An absorption efficiency of 2.40% was estimated for chicks fed this diet. Hence, absorption efficiency of inorganic Mn was 40% greater in chicks fed the purified diet than in those fed the conventional corn-soy diet.

  7. Water plasticization of extruded material made from meat and bone meal and sodium caseinate.

    Science.gov (United States)

    Garcia, Rafael A; Onwulata, Charles I; Ashby, Richard D

    2004-06-16

    Meat and bone meal (MBM) is a high protein agricultural commodity that currently has few applications other than as an animal feed. Unmodified MBM has poor functional properties, due to its low solubility. Our results from pilot plant trials demonstrate that MBM can be extrusion-processed along with sodium caseinate to produce a useful plastic material. We developed this material for use as a dog chew toy. For this application, elastic modulus (stiffness) is a key characteristic. Our results detail the relationship between ambient relative humidity and equilibrium moisture content (MC) in the material. The influence of MC on the glass transition temperature and elastic modulus reflects the plasticization of this material by water. On the basis of a comparison to a commercially available dog chew, the range of stiffness achievable with our material, 0.25-2.50 GPa, encompasses the values appropriate for a dog chew. Our results show that a particular desired stiffness can be maintained by applying an edible moisture barrier to the surface of the material.

  8. [Separation and identification of beta-casein from Chinese human milk by ion exchange chromatography-matrix-assisted laser desorption/ionization time of flight/time of flight mass spectrometry].

    Science.gov (United States)

    Huang, Yu; Ren, Haowei; Liu, Biao; Liu, Ning; Li, Meng; Wang, Dongmao

    2013-05-01

    The selective precipitation of whole casein from skimmed milk was achieved by the addition of calcium salt under acidic pH. The effects of pH, centrifugal force and final concentration of CaCl2 on the separation of casein were studied by measuring the purity of final products using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results showed that casein with the highest purity could be obtained with the pH of 4.3, the centrifugal force of 10 400 g and the final concentration of CaCl2 of 60 mmol/L. The casein was processed with DEAE anion exchange chromatography and three peaks were obtained. Then the third peak (peak III) was identified with Western-Blot method and matrix-assisted laser desorption/ionization time of flight/time of flight mass spectrometry (MALDI-TOF/TOF MS). The identification of Western-Blot showed that peak III can combine with the specificity of human milk beta-casein antibody, and it is proved to be human milk beta-casein. The fingerprints of peak III were nalyzed by Mascot searching, and the sequence coverage was 50%, further supporting it is human milk beta-casein. In conclusion, an effective method to obtain human milk beta-casein from milk samples through DEAE anion exchange chromatography was established, and it is suitable for the proteomics research requirements of the beta-casein from human milk.

  9. Caprine and ovine Greek dairy products: The official German method generates false-positive results due to κ-casein gene polymorphism.

    Science.gov (United States)

    Tsartsianidou, V; Triantafillidou, D; Karaiskou, N; Tarantili, P; Triantafillidis, G; Georgakis, E; Triantafyllidis, A

    2017-03-16

    Caseins are widely used for species identification of dairy products. Isoelectric focusing (IEF) of para-κ-casein peptide is used as the official German method for the differentiation between caprine (isoform A) and ovine (isoform B) dairy products, based on their different isoelectric points. The discrimination between Greek goat and ewe dairy products using IEF has, however, been shown to be problematic because of the existence of the ewe isoform in milk from Greek indigenous dairy goats. This could be due to nucleotide polymorphisms within the goat κ-casein gene of Greek indigenous breeds, which alter the isoelectric point of the para-κ-casein peptide and lead to false positive results. Previous DNA analysis of the goat κ-casein gene has shown high levels of polymorphism; however, no such information is available for Greek indigenous dairy goats. Therefore, 87 indigenous dairy goats were sequenced at exon IV of κ-casein gene. In total, 9 polymorphic sites were detected. Three nonsynonymous point mutations were identified, which change the isoelectric point of the goat para-κ-casein peptide so that it appears identical to that of the ewe peptide. Ten composite genotypes were reconstructed and 6 of them included the problematic point mutations. For the verification of genetic results, IEF was carried out. Both goat and ewe patterns appeared in the problematic genotypes. The frequency of these genotypes could be characterized as moderate (0.23) to high (0.60) within Greek indigenous breeds. However, this is not an issue restricted to Greece, as such genotypes have been detected in various non-Greek goat breeds. In conclusion, IEF based on the official German method is certainly inappropriate for ovine and caprine discrimination concerning Greek dairy goat products, and consequently a new method should be established.

  10. Effects of dietary protein supply on caseins, whey proteins, proteolysis and renneting properties in milk from cows grazing clover or N fertilized grass.

    Science.gov (United States)

    Hermansen, J E; Ostersen, S; Justesen, N C; Aaes, O

    1999-05-01

    The objective of this work was to examine whether variation in the amino acid supply to cows could be a reason for the reduced casein content and poorer renneting properties of milk that often occur in late summer, or whether these effects are related to proteolysis in the raw milk. In a 2 x 2 x 2 factorial design, we investigated the effects of sward (clover v. rye-grass) and supplementary feed with a high or low level of rumen-soluble N or of rumen undegradable protein on milk protein composition during the grazing season. A total of 32 Danish Holstein cows were included in the experiment. Milk protein and casein contents and the ratios casein N:total N and casein:true protein were at a minimum in late summer, whereas the contents of urea, non-protein N and whey protein were higher during this period. These seasonal effects were unrelated to either the type of supplementary feed or the type of sward; neither were they clearly related to proteolysis, although casein: true protein was related to the proteose peptone content. The results indicated that whey proteins other than alpha-lactalbumin or beta-lactoglobulin accounted for the higher proportion or concentration of whey protein in late summer. Based on a principal component analysis including variables such as citric acid, lactose and non-protein N, we suggest that the cows' energy supply during this period may be a critical factor in determining the milk protein composition, although our results were not conclusive. There was an interaction between the supplement of rumen undegradable protein and type of sward. When clover was grazed, a high supplement increased the concentrations of protein and casein in milk and the kappa-casein: total casein ratio. When rye-grass was grazed, the opposite response was found, and overall milk protein yield was not affected. The very low N content of clover in early summer reduced milk protein and casein protein during this period.

  11. Effects of Whey, Caseinate, or Milk Protein Ingestion on Muscle Protein Synthesis after Exercise.

    Science.gov (United States)

    Kanda, Atsushi; Nakayama, Kyosuke; Sanbongi, Chiaki; Nagata, Masashi; Ikegami, Shuji; Itoh, Hiroyuki

    2016-06-03

    Whey protein (WP) is characterized as a "fast" protein and caseinate (CA) as a "slow" protein according to their digestion and absorption rates. We hypothesized that co-ingestion of milk proteins (WP and CA) may be effective for prolonging the muscle protein synthesis response compared to either protein alone. We therefore compared the effect of ingesting milk protein (MP) to either WP or CA alone on muscle protein synthesis after exercise in rats. We also compared the effects of these milk-derived proteins to a control, soy protein (SP). Male Sprague-Dawley rats swam for two hours. Immediately after exercise, one of the following four solutions was administered: WP, CA, MP, or SP. Individual rats were euthanized at designated postprandial time points and triceps muscle samples collected for measurement of the protein fractional synthesis rate (FSR). FSR tended to increase in all groups post-ingestion, although the initial peaks of FSR occurred at different times (WP, peak time = 60 min, FSR = 7.76%/day; MP, peak time = 90 min, FSR = 8.34%/day; CA, peak time = 120 min, FSR = 7.85%/day). Milk-derived proteins caused significantly greater increases (p < 0.05) in FSR compared with SP at different times (WP, 60 min; MP, 90 and 120 min; CA, 120 min). Although statistical analysis could not be performed, the calculated the area under the curve (AUC) values for FSR following this trend were: MP, 534.61; CA, 498.22; WP, 473.46; and SP, 406.18. We conclude that ingestion of MP, CA or WP causes the initial peak time in muscle protein synthesis to occur at different times (WP, fast; MP, intermediate; CA, slow) and the dairy proteins have a superior effect on muscle protein synthesis after exercise compared with SP.

  12. Association and regulation of casein kinase 2 activity by adenomatous polyposis coli protein

    Science.gov (United States)

    Homma, Miwako Kato; Li, Dongxia; Krebs, Edwin G.; Yuasa, Yasuhito; Homma, Yoshimi

    2002-01-01

    Mutations in the adenomatous polyposis coli (APC) gene are responsible for familial adenomatous polyposis coli and also sporadic colorectal cancer development. By using antibodies raised against the N-terminal region of APC protein, we have detected the variable masses of endogenous APC proteins in individual cell lines established from human colorectal carcinomas caused by nonsense mutations of the gene. Phosphorylation of immunoprecipitates of full-length and truncated APC were observed in in vitro kinase reaction, indicating association of APC with protein kinase activity. The kinase activity complexed with APC was sensitive to heparin and used GTP as phosphoryl donor, suggesting an involvement of casein kinase 2 (CK2). Both CK2α- and β-subunits were found to associate with APC in immunoprecipitates as well as in pull-down assays, with preferential interaction of APC with tetrameric CK2 holoenzyme. In synchronized cell populations, the association of APC with CK2 was cell cycle dependent, with the highest association in G2/M. Unexpectedly, APC immunoprecipitates containing full-length APC protein inhibited CK2 in vitro, whereas immunoprecipitates of truncated APC had little effect. This was confirmed by using recombinant APC, and the inhibitory region was localized to the C terminus of APC between residues 2086 and 2394. Overexpression of this fragment in SW480 cells suppressed cell proliferation rates as well as tumorigenesis. These results demonstrate a previously uncharacterized functional interaction between the tumor suppressor protein APC and CK2 and suggest that growth-inhibitory effects of APC may be regulated by inhibition of CK2. PMID:11972058

  13. Functional analysis of Trichoderma reesei CKIIα2, a catalytic subunit of casein kinase II.

    Science.gov (United States)

    Wang, Mingyu; Yang, Hui; Zhang, Meiling; Liu, Kuimei; Wang, Hanbin; Luo, Yi; Fang, Xu

    2015-07-01

    Trichoderma reesei is the most important industrial cellulase-producing filamentous fungus. Although its molecular physiology has been investigated, the signal transduction pathways are not fully understood. In particular, the role of casein kinase II (CKII) is not yet clear. In this work, we carried out functional investigations on a catalytic subunit of CKII, CKIIα2. Comparison of the phenotypic features of T. reesei parent and Δck2α2 strains showed significant changes following ck2α2 disruption. T. reesei Δck2α2 form significantly smaller mycelial pellets in glucose-containing liquid minimum media, have shorter and fewer branch hyphae, produce smaller amounts of chitinases, produce more spores, show more robust growth on glucose-containing agar plates, and consume glucose at a significantly higher rate. Suggestions can be made that CKIIα2 governs chitinase expression, and the disruption of ck2α2 results in lower levels of chitinase production, leading to a weaker cell wall disruption capability, further resulting in weaker hyphal branching, which eventually leads to smaller mycelial pellets in liquid media. Further conclusions can be made that CKIIα2 is involved in repression of sporulation and glucose metabolism, which is consistent with the proposal that CKIIα2 represses global metabolism. These observations make the deletion of ck2α2 a potentially beneficial genetic disruption for T. reesei during industrial applications, as smaller mycelial pellets, more spores and more robust glucose metabolism are all desired traits for industrial fermentation. This work reports novel unique functions of a CKII catalytic subunit and is also the first genetic and physiological investigation on CKII in T. reesei.

  14. A review of gluten- and casein-free diets for treatment of autism: 2005–2015

    Science.gov (United States)

    Elder, Jennifer Harrison; Kreider, Consuelo Maun; Schaefer, Nancy M.; de Laosa, Mary B.

    2015-01-01

    Background The gluten free, casein free (GFCF) diet is heralded by strong anecdotal parental reports to greatly improve and even “cure” symptoms of Autism Spectrum Disorders (ASD). Yet to date, little conclusive empirical evidence exists supporting its use. Objective The purpose of this paper is to provide an overview of the state of the recent evidence regarding use of GFCF diet for treatment of individuals with ASD. Methods Five database providers (PubMed, Web of Knowledge, EBSCO, ProQuest, and WorldCat) were used to search 19 databases yielding a total of 491 articles that were published through February 2015. Peer reviewed articles published between 2005 and February 2015 were included for review if study participants were identified as having ASD and investigated the effects of the GFCF diet on ASD behaviors or the relationship between the diet and these behaviors. Results Evaluation of search results yielded 11 reviews, 7 group experimental studies including 5 randomized controlled trials, 5 case reports, and 4 group observational studies published during the last 10 years. These studies represent a marked increase in number of reported studies as well as increased scientific rigor in investigation of GFCF diets in ASD. Conclusions While strong empirical support for the GFCF diet in ASD is currently lacking, studies point to the need for identifying subsets of individuals (e.g., those with documented gastrointestinal abnormalities) who may be the best responders to the GFCF diet. Identifying these subsets is critically needed to enhance rigor in this research area. Until rigorous research supporting use of GFCF diet is reported, clinicians should continue use caution and consider several factors when advising regarding implementation of the GFCF diet for individuals with ASD. PMID:28111520

  15. The Effect of Casein Protein Prior to Sleep on Fat Metabolism in Obese Men

    Directory of Open Access Journals (Sweden)

    Amber W. Kinsey

    2016-07-01

    Full Text Available We have previously shown that ingesting protein at night before sleep is either beneficial or non-detrimental to metabolism, health, and body composition in obese women. However, the overnight protein-induced lipolytic actions and mechanism for improved metabolism and body composition have not been fully established. Therefore, in a crossover design, twelve obese men (age, 27.0 ± 2.2 years were randomly assigned to ingest (within 30 min of sleep casein protein (CAS, 120 kcal or a non-nutritive placebo (PLA before going to sleep. Markers of fat metabolism (lipolysis, substrate utilization, growth hormone, insulin, glucose, resting energy expenditure (REE, and appetite (questionnaire and ghrelin were measured. During sleep and the next morning, interstitial glycerol from the subcutaneous abdominal adipose tissue (SCAAT was measured using microdialysis. There were no differences in SCAAT glycerol (overnight: CAS, 177.4 ± 26.7; PLA, 183.8 ± 20.2 μmol/L; morning: CAS, 171.6 ± 19.1; PLA, 161.5 ± 18.6 μmol/L, substrate utilization, REE, or any blood markers between CAS and PLA. Desire to eat was greater for CAS compared to baseline (p = 0.03, but not different from PLA (baseline: 39 ± 6, CAS: 62 ± 8, PLA: 55 ± 5 mm. CAS consumption before sleep did not affect fat or glucose metabolism, REE, or suppress appetite in hyperinsulemic obese men. CAS may be consumed before sleep without impeding overnight or morning fat metabolism in young, obese men.

  16. Effect Of Five Proteases Including Alcalase, Flavourzyme, Papain, Proteinase K And Trypsin On Antioxidative Activities Of Casein Hydrolysate From Goat Milk

    Directory of Open Access Journals (Sweden)

    Shu Guowei

    2015-12-01

    Full Text Available Oxidation was related to the pathogenesis of human diseases. Adequate intake of antioxidant activity of food can reduce the levels of free radicals, prevent lipid peroxidation, and help the body against diseases. In the paper, casein from goat milk was hydrolyzed by five commercial proteases, namely, Alcalase, flavourzyme, papain, proteinase K and trypsin. The antioxidant activities of casein hydrolysates were assessed by evaluating hydrolysis degree, DPPH radical-scavenging activity, metal-chelating activity and superoxide radical scavenging activity. The results showed as follows: the DH of proteinase K, Alcalase, and trypsin were higher significantly than those of papain and flavourzyme. The Fe2+-chelation activity and superoxide radical scavenging activity of casein hydrolysates from goat milk by Alcalase was higher than the others, the DPPH scavenging activities of casein hydrolysates by Alcalase and papain was higher than the others and the DPPH scavenging activities by Alcalase and papain had no significant diffierence (p<0.05, so the optimal proteinase for hydrolysis casein from goat milk to produce antioxidant peptide was Alcalase.

  17. Effect of casein genes - beta-LGB, DGAT1, GH, and LHR - on milk production and milk composition traits in crossbred Holsteins.

    Science.gov (United States)

    Molee, A; Poompramun, C; Mernkrathoke, P

    2015-03-30

    The objectives of this study were to determine the effects of a single gene and composite genotype of the casein gene family, including the beta-lactoglobulin gene (beta-LGB), acyl-CoA: diacylglycerol acyltransferase 1 gene (DGAT1), growth hormone gene (GH), and luteinizing hormone receptor gene (LHR) on milk yield, milk composition, the percentage of fat, protein, solids-not-fat, and total solid in crossbred Holsteins. A total of 231 crossbred Holstein cows were examined for the study. The genotype of the beta-casein gene was analyzed by allele-specific polymerase chain reaction, while the alpha-S1, alpha-S2, kappa-casein, DGAT1, beta-LGB, and GH genes were analyzed using a polymerase chain reaction-restriction fragment length polymorphism assay. The association between genes and milk yield and milk composition was analyzed. Three pairs of genes, for which significant associations were detected, were beta + kappa-casein, DGAT1 + beta-casein, and GH + beta-LGB. In the single-gene model, most loci are significantly associated with traits. A significant association between the composite genotype and the traits was detected in all composite genotypes. GH + beta-LGB appears to be the most suitable variants for improving milk production and percentage of milk protein. Overall, the effects of the composite genotype and single gene were different. A physical or functional relationship between genes is necessary for investigating gene markers.

  18. Casein-Coated Fe5C2 Nanoparticles with Superior r2 Relaxivity for Liver-Specific Magnetic Resonance Imaging.

    Science.gov (United States)

    Cowger, Taku A; Tang, Wei; Zhen, Zipeng; Hu, Kai; Rink, David E; Todd, Trever J; Wang, Geoffrey D; Zhang, Weizhong; Chen, Hongmin; Xie, Jin

    2015-01-01

    Iron oxide nanoparticles have been extensively used as T2 contrast agents for liver-specific magnetic resonance imaging (MRI). The applications, however, have been limited by their mediocre magnetism and r2 relaxivity. Recent studies show that Fe5C2 nanoparticles can be prepared by high temperature thermal decomposition. The resulting nanoparticles possess strong and air stable magnetism, suggesting their potential as a novel type of T2 contrast agent. To this end, we improve the synthetic and surface modification methods of Fe5C2 nanoparticles, and investigated the impact of size and coating on their performances for liver MRI. Specifically, we prepared 5, 14, and 22 nm Fe5C2 nanoparticles and engineered their surface by: 1) ligand addition with phospholipids, 2) ligand exchange with zwitterion-dopamine-sulfonate (ZDS), and 3) protein adsorption with casein. It was found that the size and surface coating have varied levels of impact on the particles' hydrodynamic size, viability, uptake by macrophages, and r2 relaxivity. Interestingly, while phospholipid- and ZDS-coated Fe5C2 nanoparticles showed comparable r2, the casein coating led to an r2 enhancement by more than 2 fold. In particular, casein coated 22 nm Fe5C2 nanoparticle show a striking r2 of 973 mM(-1)s(-1), which is one of the highest among all of the T2 contrast agents reported to date. Small animal studies confirmed the advantage of Fe5C2 nanoparticles over iron oxide nanoparticles in inducing hypointensities on T2-weighted MR images, and the particles caused little toxicity to the host. The improvements are important for transforming Fe5C2 nanoparticles into a new class of MRI contrast agents. The observations also shed light on protein-based surface modification as a means to modulate contrast ability of magnetic nanoparticles.

  19. Effect of soluble calcium on the renneting properties of casein micelles as measured by rheology and diffusing wave spectroscopy.

    Science.gov (United States)

    Sandra, S; Ho, M; Alexander, M; Corredig, M

    2012-01-01

    Addition of calcium chloride to milk has positive effects on cheese-making because it decreases coagulation time, creates firmer gels, and increases curd yield. Although addition of calcium chloride is a widely used industrial practice, the effect of soluble calcium on the preliminary stages of gelation is not fully understood. In addition, it is not known whether the manner of addition and equilibration of the soluble calcium would affect the rennetability of the casein micelles. Therefore, the aim of this paper was to study the details of the coagulation behavior of casein micelles in the presence of additional calcium, and to elucidate whether the manner in which this cation is added (directly as calcium chloride or by gradual exchange through dialysis) affects the functionality of the micelles. Calcium was added as CaCl(2) (1 mM final added concentration) directly to skim milk or indirectly using dialysis against 50 volumes of milk. Additional soluble calcium did not affect the primary phase of the renneting reaction, as demonstrated by the analysis of the casein macropeptide (CMP) released in solution; however, it shortened the coagulation time of the micelles and increased the firmness of the gel. The turbidity parameter of samples with or without calcium showed that similar amounts of CMP were needed for particle interactions to commence. However, the amount of CMP released at the point of gelation, as indicated by rheology, was lesser for samples with added calcium, which can be attributed to a greater extent of calcium bridging on the surface or between micelles. The results also showed that the manner in which calcium was presented to the micelles did not influence the mechanism of gelation.

  20. Factors that influence the membrane area of a multistage microfiltration process required to produce a micellar casein concentrate.

    Science.gov (United States)

    Hurt, Emily E; Barbano, David M

    2015-04-01

    The objective of the work reported in this paper was to develop a theoretical model to determine the effect of type of microfiltration (MF)-process feed, number of stages, and flux on the minimization of the MF membrane area required to produce a 95% serum protein-reduced micellar casein concentrate. The MF feed, number of stages, and flux were all factors that had an effect on the MF membrane area and should be taken into consideration when designing a MF system to produce a 95% serum protein-reduced micellar casein concentrate. Feeding the MF process with a diluted ultrafiltration retentate (DUR) diluted to the protein concentration of skim milk, as opposed to skim milk, reduced the required membrane area by 36% for a 5-stage process. When DUR was the MF feed, feed protein concentration, which depended on the number of MF stages, was optimized. The DUR protein concentration that minimized the required MF membrane area was 2.47, 3.85, 4.77, and 5.41% for a 2-, 3-, 4-, or 5-stage MF process, respectively. For a 5-stage process, increasing the protein concentration of the feed from 3.2 to 5.4% decreased the required MF membrane area by 10%. It was also found that as the number of stages increased from 2 to 5, the required MF membrane area decreased by 39%, when the MF feed was DUR at the optimal feed protein concentration. Finally, increasing the flux from 50 to 60 kg/m(2) per hour decreased the required MF membrane area by 17% when the MF feed was DUR at the optimal MF feed protein concentration. Overall, using DUR as a feed for MF could reduce the amount of MF membrane area required to make a 95% serum protein-reduced micellar casein concentrate.

  1. Casein phosphopeptides drastically increase the secretion of extracellular proteins in Aspergillus awamori. Proteomics studies reveal changes in the secretory pathway

    Directory of Open Access Journals (Sweden)

    Kosalková Katarina

    2012-01-01

    Full Text Available Abstract Background The secretion of heterologous animal proteins in filamentous fungi is usually limited by bottlenecks in the vesicle-mediated secretory pathway. Results Using the secretion of bovine chymosin in Aspergillus awamori as a model, we found a drastic increase (40 to 80-fold in cells grown with casein or casein phosphopeptides (CPPs. CPPs are rich in phosphoserine, but phosphoserine itself did not increase the secretion of chymosin. The stimulatory effect is reduced about 50% using partially dephosphorylated casein and is not exerted by casamino acids. The phosphopeptides effect was not exerted at transcriptional level, but instead, it was clearly observed on the secretion of chymosin by immunodetection analysis. Proteomics studies revealed very interesting metabolic changes in response to phosphopeptides supplementation. The oxidative metabolism was reduced, since enzymes involved in fermentative processes were overrepresented. An oxygen-binding hemoglobin-like protein was overrepresented in the proteome following phosphopeptides addition. Most interestingly, the intracellular pre-protein enzymes, including pre-prochymosin, were depleted (most of them are underrepresented in the intracellular proteome after the addition of CPPs, whereas the extracellular mature form of several of these secretable proteins and cell-wall biosynthetic enzymes was greatly overrepresented in the secretome of phosphopeptides-supplemented cells. Another important 'moonlighting' protein (glyceraldehyde-3-phosphate dehydrogenase, which has been described to have vesicle fusogenic and cytoskeleton formation modulating activities, was clearly overrepresented in phosphopeptides-supplemented cells. Conclusions In summary, CPPs cause the reprogramming of cellular metabolism, which leads to massive secretion of extracellular proteins.

  2. Cloning and expression in Escherichia coli of a new gene of Schistosoma japonicum encoding casein kinase Ⅱ beta subunit

    Institute of Scientific and Technical Information of China (English)

    彭寨玉; 余新炳; 吴忠道; 徐劲; 吴德; 李孜

    2004-01-01

    Background Nowadays it is now a focus topic in schistosomiasis research to find ideal vaccine candidates and new drug targets for developing anti-schistosomiasis vaccine. We cloned a new gene, casein kinase Ⅱ beta subunit, of Schistosoma japonicum (S. japonicum) and express it in Escherichia coli (E.coli).Methods The ESTs obtained in our laboratory were analyzed by homologous searching, and a new gene was recognized. The full-length cDNA of the new gene was obtained by joining the 3'RACE PCR fragment and the EST clone. To express the new gene, the cDNA was cloned into pGEX-4T-1 vector and then transformed into E.coli JM109. The recombinant protein was analyzed by SDS-PAGE and Western-blot. Results A 908 bp cDNA was isolated from S. japonicum and identified to be casein kinase Ⅱ beta subunit gene by sequence analysis. The open reading frame of the gene encodes a protein of 217 amino acids exhibiting 75.8%, 75.8%, 73.9%, 68.2%, 51.6% identity to the amino acids sequence of the corresponding genes of Homo sapiens (H. sapiens), Xenopus laevi (X. laevi), Drosophila melanogaster (D. melanogaster), Caenorhabditis elegan (C. elegan), and Schizosaccharomyces pombe (S. promber) respectively. The predicted molecular weight of the protein was 24.921 kDa. The new cDNA sequence had been submitted to GenBank, and its accession number is AY241391. This cDNA was subcloned into the pGEX-4T-1 vector and expressed in E.coli JM109.The recombinant protein could be recognized by the S. japonicum infected rabbit serum. Conclusion The full-length cDNA sequences encoding S. japonicum casein kinase Ⅱ beta subunit were firstly sequenced, cloned, and expressed in E.coli.

  3. Comparison of milk oligosaccharides between goats with and without the genetic ability to synthesize αs1-casein

    Science.gov (United States)

    Meyrand, M.; Dallas, D.C.; Caillat, H.; Bouvier, F.; Martin, P.; Barile, D.

    2014-01-01

    Milk oligosaccharides (OS)—free complex carbohydrates—confer unique health benefits to the nursing neonate. Though human digestive enzymes cannot degrade these sugars, they provide nourishment to specific commensal microbes and act as decoys to prevent the adhesion of pathogenic micro-organisms to gastrointestinal cells. At present, the limited quantities of human milk oligosaccharides (HMO) impede research on these molecules and their potential applications in functional food formulations. Considerable progress has been made in the study of OS structures; however, the synthetic pathways leading to their synthesis in the mammary gland are poorly understood. Recent studies show that complex OS with fucose and N-acetyl neuraminic acid (key structural elements of HMO bioactivity) exist in goat milk. Polymorphisms in the CSN1S1 locus, which is responsible for synthesis of αs1-casein, affect lipid and casein micelle structure in goat milk. The present study sought to determine whether CSN1S1 polymorphisms also influence goat milk oligosaccharide (GMO) production and secretion. The GMO compositions of thirty-two goat milk samples, half of which were from genotype A/A (αs1-casein producers) and half from genotype O/O (αs1-casein non-producers), were determined with nanoflow liquid chromatography high-accuracy mass spectrometry. This study represents the most exhaustive characterization of GMO to date. A systematic and comprehensive GMO library was created, consolidating information available in the literature with the new findings. Nearly 30 GMO, 11 of which were novel, were confirmed via tandem mass spectrometric analyses. Six fucosylated OS were identified; 4 of these matched HMO compositions and three were identified for the first time in goat milk. Importantly, multivariate statistical analysis demonstrated that the OS profiles of the A/A and O/O genotype milks could be discriminated by the fucosylated OS. Quantitative analysis revealed that the goat milk

  4. Short communication: Casein hydrolysate and whey proteins as excipients for cyanocobalamin to increase intestinal absorption in the lactating dairy cow.

    Science.gov (United States)

    Artegoitia, V M; de Veth, M J; Harte, F; Ouellet, D R; Girard, C L

    2015-11-01

    Bioavailability of vitamin B12 is low in humans and animals. Improving vitamin B12 absorption is important for optimal performance in dairy cows and for increasing vitamin B12 concentrations in milk for human consumption. However, when supplemented in the diet, 80% of synthetic vitamin B12, cyanocobalamin (CN-CBL), is degraded in the rumen of dairy cows and only 25% of the amount escaping destruction in the rumen disappears from the small intestine between the duodenal and ileal cannulas. In pigs, vitamin B12 from milk is more efficiently absorbed than synthetic CN-CBL. The objective of this study was to determine the efficacy of casein hydrolysate and whey proteins as excipients for CN-CBL to increase portal-drained viscera (PDV) flux of the vitamin in lactating dairy cows. Four multiparous lactating Holstein cows (237 ± 17 DIM) equipped with a rumen cannula and catheters in the portal vein and a mesenteric artery were used in a randomized Youden square design. They were fed every 2 h to maintain steady digesta flow. On experimental days, they received a postruminal bolus of (1) CN-CBL alone (0.1 g), (2) CN-CBL (0.1 g) + casein hydrolysate (10 g), or (3) CN-CBL (0.1 g) + whey proteins (10 g). Starting 30 min after the bolus, blood samples were taken simultaneously from the 2 catheters every 15 min during the first 2 h and then every 2 h until 24 h postbolus. Milk yield, DMI, and vitamin B12 portal-arterial difference and PDV flux were analyzed using the MIXED procedure of SAS. Milk yield and DMI were not affected by treatments. The portal-arterial difference of vitamin B12 during the 24-h period following the bolus of vitamin was greater when the vitamin was given in solution with casein hydrolysate (2.9 ± 4.6 pg/mL) than alone (-17.5 ± 5.2 pg/mL) or with whey protein (-13.4 ± 4.2 pg/mL). The treatment effects were similar for the PDV flux. The present results suggest that CN-CBL given with casein hydrolysate increases vitamin B12 absorption as compared with

  5. Determination of casein content in milk by Kjeldahl method%凯氏定氮法测定牛乳中酪蛋白含量

    Institute of Scientific and Technical Information of China (English)

    李宏梁; 高洁

    2012-01-01

    酪蛋白是牛乳中的特征性成分,其含量可作为牛乳掺假检验的定量指标。实验结果表明等电点法结合凯氏定氮法能够有效地检测牛乳中酪蛋白含量,测定结果准确,重复性好。实验验证了纯牛乳中酪蛋白含量为2.5%。%Casein is the characteristic composition of milk, its content can be used as quantitative indicator of milk adulteration. The results showed that isoelectric point method combined with the Kjeldahl method could detect casein content in milk effectively, the results were accurate and reproduced well. The experiment verified that casein content was about 2.5% in pure milk.

  6. Comparison of casein and whey in diets on performance, immune responses and metabolomic profile of weaning pigs challenged with E.coli F4

    DEFF Research Database (Denmark)

    Sugiharto, Sugiharto; Jensen, Bent Borg; Hedemann, Mette Skou

    2014-01-01

    The differences in amino acid composition in casein and whey have been thought to exert different immunomodulatory and metabolic effects. The objective of this study was to compare the effects of casein and whey on performance, immune responses and plasma metabolomic profile of weanling pigs...... challenged with E. coli F4. Two factorial experiments involving 24 weanling pigs were conducted. Diets containing casein or whey, and challenge with E. coli O149:F4 or not, were the two factors. Blood was sampled at the day before challenge and 4 and 7 days postchallenge. For measurement of mucosal immune...... responses and intestinal dimensions, samples were collected from the small intestine (SI) immediately after killing at 7 days postchallenge. Feeding the whey-diet decreased (P

  7. In vitro digestibility of beta-casein and beta-lactoglobulin under simulated human gastric and duodenal conditions: A multi-laboratory evaluation

    DEFF Research Database (Denmark)

    Mandalari, G.; Adel-Patient, K.; Barkholt, Vibeke;

    2009-01-01

    Initially the resistance to digestion of two cow's milk allergens, beta-casein, and beta-lactoglobulin (beta-Lg), was compared using a "high-protease assay" and a "low-protease assay" in a single laboratory. The low-protease assay represents an alternative standardised protocol mimicking conditions...... found in the gastrointestinal tract. For the high-protease assay, both proteins were incubated with either pepsin or pancreatin and digestion monitored by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and reverse phase-high performance liquid chromatography. The low-protease assay involved...... gastroduodenal digestion in the presence or absence of phosphatidylcholine (PC). Both beta-casein and beta-Lg were susceptible to hydrolysis by pepsin and pancreatin in the high-protease assay. In contrast, the kinetics of beta-casein digestion in the low-protease assay were slower, beta-Lg being pepsin...

  8. A peptidomic approach to study the contribution of added casein proteins to the peptide profile in Spanish dry-fermented sausages.

    Science.gov (United States)

    Mora, Leticia; Escudero, Elizabeth; Aristoy, M-Concepción; Toldrá, Fidel

    2015-11-06

    Peptidomics is a necessary alternative in the analysis of naturally generated peptides in dry-fermented processing. The intense proteolysis occurred during the processing of dry-fermented sausages is due to the action of endopeptidases and exopeptidases from both, endogenous muscle origin and lactic acid bacteria (LAB) added in the starter. Sodium caseinate is frequently used as an additive in this type of products because of its emulsifying properties, and consequently influences the protein profile available during the proteolysis. In this study, a mass spectrometry approach has been used to determine the impact of added sodium caseinate in the final peptide profile as well as to analyse its possible influence in the presence of certain previously described casein-derived bioactive peptides.

  9. Technology on Modification of Casein and properties of Productions%酪素改性的技术手段与改性产品的性能特点

    Institute of Scientific and Technical Information of China (English)

    申晓庆; 兰云军; 许晓红

    2009-01-01

    Modified graft principle of casein was introduced. Different technical means of modified casein and the characteristics of productions were described and classified.%介绍酪素的接枝改性原理,分类描述了酪素改性的技术手段与改性产品的性能特点.

  10. In Vitro Proliferation and Anti-Apoptosis of the Papain-Generated Casein and Soy Protein Hydrolysates towards Osteoblastic Cells (hFOB1.19

    Directory of Open Access Journals (Sweden)

    Xiao-Wen Pan

    2015-06-01

    Full Text Available Casein and soy protein were digested by papain to three degrees of hydrolysis (DH 7.3%–13.3%, to obtain respective six casein and soy protein hydrolysates, aiming to clarify their in vitro proliferation and anti-apoptosis towards a human osteoblastic cell line (hFOB1.19 cells. Six casein and soy protein hydrolysates at five levels (0.01–0.2 mg/mL mostly showed proliferation as positive 17β-estradiol did, because they conferred the osteoblasts with cell viability of 100%–114% and 104%–123%, respectively. The hydrolysates of higher DH values had stronger proliferation. Casein and soy protein hydrolysates of the highest DH values altered cell cycle progression, and enhanced cell proportion of S-phase from 50.5% to 56.5% and 60.5%. The two also antagonized etoposide- and NaF-induced osteoblast apoptosis. In apoptotic prevention, apoptotic cells were decreased from 31.6% to 22.6% and 15.6% (etoposide treatment, or from 19.5% to 17.7% and 12.4% (NaF treatment, respectively. In apoptotic reversal, soy protein hydrolysate decreased apoptotic cells from 13.3% to 11.7% (etoposide treatment, or from 14.5% to 11.0% (NaF treatment, but casein hydrolysate showed no reversal effect. It is concluded that the hydrolysates of two kinds had estradiol-like action on the osteoblasts, and soy protein hydrolysates had stronger proliferation and anti-apoptosis on the osteoblasts than casein hydrolysates.

  11. Protein feeding pattern, casein feeding, or milk-soluble protein feeding did not change the evolution of body composition during a short-term weight loss program.

    Science.gov (United States)

    Adechian, Solange; Balage, Michèle; Remond, Didier; Migné, Carole; Quignard-Boulangé, Annie; Marset-Baglieri, Agnès; Rousset, Sylvie; Boirie, Yves; Gaudichon, Claire; Dardevet, Dominique; Mosoni, Laurent

    2012-10-15

    Studies have shown that timing of protein intake, leucine content, and speed of digestion significantly affect postprandial protein utilization. Our aim was to determine if one can spare lean body mass during energy restriction by varying the quality and the timing of protein intake. Obese volunteers followed a 6-wk restricted energy diet. Four groups were compared: casein pulse, casein spread, milk-soluble protein (MSP, = whey) pulse, and MSP spread (n = 10-11 per group). In casein groups, caseins were the only protein source; it was MSP in MSP groups. Proteins were distributed in four meals per day in the proportion 8:80:4:8% in the pulse groups; it was 25:25:25:25% in the spread groups. We measured weight, body composition, nitrogen balance, 3-methylhistidine excretion, perception of hunger, plasma parameters, adipose tissue metabolism, and whole body protein metabolism. Volunteers lost 7.5 ± 0.4 kg of weight, 5.1 ± 0.2 kg of fat, and 2.2 ± 0.2 kg of lean mass, with no difference between groups. In adipose tissue, cell size and mRNA expression of various genes were reduced with no difference between groups. Hunger perception was also never different between groups. In the last week, due to a higher inhibition of protein degradation and despite a lower stimulation of protein synthesis, postprandial balance between whole body protein synthesis and degradation was better with caseins than with MSP. It seems likely that the positive effect of caseins on protein balance occurred only at the end of the experiment.

  12. A novel method for in Situ detection of hydrolyzable casein fragments in a cheese matrix by antibody phage display technique and CLSM

    DEFF Research Database (Denmark)

    Duan, Zhi; Brüggemann, Dagmar Adeline; Siegumfeldt, Henrik

    2009-01-01

    was successfully developed for the detection of scFvs binding to different alpha(s1)-casein fragments inside a cheese matrix by CLSM. To our knowledge, this is the first demonstrated immunofluorescent labeling method for in situ analysis of proteolysis phenomena in the cheese matrix. Additionally, this technique......A novel method to monitor in situ hydrolyzable casein fragments during cheese ripening by using immunofluorescent labeling and confocal laser scanning microscopy (CLSM) was developed. Monoclonal single chain variable fragments of antibody (scFvs) were generated by antibody phage display toward...

  13. Importance of casein micelle size and milk composition for milk gelation.

    Science.gov (United States)

    Glantz, M; Devold, T G; Vegarud, G E; Lindmark Månsson, H; Stålhammar, H; Paulsson, M

    2010-04-01

    The economic output of the dairy industry is to a great extent dependent on the processing of milk into other milk-based products such as cheese. The yield and quality of cheese are dependent on both the composition and technological properties of milk. The objective of this study was to evaluate the importance and effects of casein (CN) micelle size and milk composition on milk gelation characteristics in order to evaluate the possibilities for enhancing gelation properties through breeding. Milk was collected on 4 sampling occasions at the farm level in winter and summer from dairy cows with high genetic merit, classified as elite dairy cows, of the Swedish Red and Swedish Holstein breeds. Comparisons were made with milk from a Swedish Red herd, a Swedish Holstein herd, and a Swedish dairy processor. Properties of CN micelles, such as their native and rennet-induced CN micelle size and their zeta-potential, were analyzed by photon correlation spectroscopy, and rennet-induced gelation characteristics, including gel strength, gelation time, and frequency sweeps, were determined. Milk parameters of the protein, lipid, and carbohydrate profiles as well as minerals were used to obtain correlations with native CN micelle size and gelation characteristics. Milk pH and protein, CN, and lactose contents were found to affect milk gelation. Smaller native CN micelles were shown to form stronger gels when poorly coagulating milk was excluded from the correlation analysis. In addition, milk pH correlated positively, whereas Mg and K correlated negatively with native CN micellar size. The milk from the elite dairy cows was shown to have good gelation characteristics. Furthermore, genetic progress in relation to CN micelle size was found for these cows as a correlated response to selection for the Swedish breeding objective if optimizing for milk gelation characteristics. The results indicate that selection for smaller native CN micelles and lower milk pH through breeding would

  14. Casein and soya-bean protein have different effects on whole body protein turnover at the same nitrogen balance

    DEFF Research Database (Denmark)

    Nielsen, K; Kondrup, J; Elsner, Petteri

    1994-01-01

    , or hydrolysed soya-bean protein at a level of 9.1 g/kg BW per d. The diets, which were isoenergetic with the same carbohydrate: fat ratio, were given as a continuous intragastric infusion for at least 4 d. During the last 19 h 15N-glycine (a primed continuous infusion) was given intragastrically and 15N...... synthesis. The protein diets produced a positive N balance which was independent of the protein source. Intact and hydrolysed casein increased protein synthesis 2.6- and 2.0-fold respectively, compared with the protein-free diet. Protein degradation increased 1.4- and 1.2-fold respectively. Hydrolysed soya......-bean protein did not increase protein synthesis but decreased protein degradation by 35% compared with the protein-free diet. Compared with the hydrolysed soya-bean protein, intact casein resulted in 2.2- and 2.8-fold higher rates of protein synthesis and degradation respectively. These results are not easily...

  15. Synthesis and biological response of casein-based silica nano-composite film for drug delivery system.

    Science.gov (United States)

    Ma, Jianzhong; Xu, Qunna; Zhou, Jianhua; Zhang, Jing; Zhang, Limin; Tang, Huiru; Chen, Lihong

    2013-11-01

    Casein possesses many interesting properties that make it a good candidate for conventional and novel drug delivery systems. In this study, casein-based silica nano-composite was prepared via double in situ method, and the as-prepared latex particles were evaluated in terms of their morphology and size through transmission electron microscopy (TEM). The film morphology was investigated by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX), and the mechanical property and response behavior of the films as a function of silica content were discussed. Ibuprofen was used as the model drug. The drug load and release properties were studied by solid-state nuclear magnetic resonance (solid-state NMR), Fourier transform infrared (FT-IR), SEM and in vitro test. The composite latex particle showed a stable core-shell structure, and the film exhibited a regular surface with even SiO2 distribution. The drug load efficiency of the composite films increased with adding silica because of the adsorption of the drugs on the silica. In an acidic release medium, the ibuprofen-loaded composite showed a slower drug release dependent on the silica content. These behaviors were most likely due to the reduced diffusion rate of the drug through the composite microsphere, which resulted from the interaction between the silica and the drug.

  16. The investigation of the secondary structures of various peptide sequences of β-casein by the multicanonical simulation method

    Science.gov (United States)

    Yaşar, F.; Çelik, S.; Köksel, H.

    2006-05-01

    The structural properties of Arginine-Glutamic acid-Leucine-Glutamic acid-Glutamic acid-Leucine-Asparagine-Valine-Proline-Glycine (RELEELNVPG, in one letter code), Glutamic acid-Glutamic acid-Glutamine-Glutamine-Glutamine-Threonine-Glutamic acid (EEQQQTE) and Glutamic acid-Aspartic acid-Glutamic acid-Leucine-Glutamine-Aspartic acid-Lysine-Isoleucine (EDELQDKI) peptide sequences of β-casein were studied by three-dimensional molecular modeling. In this work, the three-dimensional conformations of each peptide from their primary sequences were obtained by multicanonical simulations. With using major advantage of this simulation technique, Ramachandran plots were prepared and analysed to predict the relative occurrence probabilities of β-turn, γ-turn and helical structures. Structural predictions of these sequences of β-casein molecule indicate the presence of high level of helical structures and βIII-turns. The occurrence probabilities of inverse and classical β-turns were low. The probability of helical structure of each sequence significantly decreased when the temperature increased. Our results show these peptides have highly helical structure and better agreement with the results of spectroscopic techniques and other prediction methods.

  17. Genetic polymorphism of beta-casein gene and its associations with milk traits in Holstein-Friesian cows

    Directory of Open Access Journals (Sweden)

    Teodor Bugeac

    2015-05-01

    Full Text Available In animal breeding finding and using effective genetic markers for improving important traits it is a continuous challenge. In this respect, several genetic markers were associated in cattle with increased milk production or a better milk quality. This proved to be a useful tool for improving certain traits by selecting individuals carriers of allelic variants that have an effect on a desirable trait. In particular, positive associations between certain alleles found at the milk protein loci with some milk production traits convincingly demonstrated in several cattle breeds. Although, in some cases the results obtained in various studies were not in agreement and varied between breeds or populations. Therefore the objective of this study was to establish associations (if any between alleles found at the beta-casein (CSN2 locus and some milk production traits (milk yield and fat, protein, casein and lactose content in a Holstein-Friesian population reared in Romania. Genetic variants at CSN2 locus were identified by isoelectric focusing (IEF of milk samples. In order to determine milk composition the samples were analysed with MilkoScan FT 6000. For the statistical analysis of data SPSS v.19 for Windows was used. At the CSN2 locus four alleles and seven genotypes were identified in the analyzed cattle population. The cows carriers of CSN2 A2 allele produced the highest milk yield and the highest milk protein content, this result being in agreement with other previous studies.

  18. Short communication: the beta-casein (CSN2) silent allele C1 is highly spread in goat breeds.

    Science.gov (United States)

    Chessa, S; Rignanese, D; Küpper, J; Pagnacco, G; Erhardt, G; Caroli, A

    2008-11-01

    Several single nucleotide polymorphisms have been identified in the goat milk casein genes, most of them modifying the amino acid sequence of the coded protein. At least 9 variants have been found in goat beta-CN (CSN2); 6 of them were characterized at the DNA level (A, A1, C, E, 0, and 0'), whereas the other 3 variants were described only at the protein level. The recently identified silent A1 allele is characterized by a C-->T transition at the 180th nucleotide of the ninth exon. In the present work, typing results from different breeds (3 Italian, 3 German, and a composite of African breeds for a total of 335 samples) demonstrated that the same mutation is carried by the CSN2*C allele. In addition, the T nucleotide at the 180th nucleotide of the ninth exon was always associated with CSN2*C in all the breeds analyzed. Thus, another silent allele occurs at goat CSN2 and can be named CSN2*C1. The much wider distribution of C1 with respect to the A1 allele indicates that the single nucleotide polymorphisms characterizing the silent mutation originated from CSN2*C. A method for the identification of this allele simultaneously with 5 of the 6 DNA-characterized alleles is also proposed. The mutation involved codifies for the same protein of the C allele; nevertheless, its location in the 3' untranslated region of the gene might affect the specific casein expression.

  19. Development and Validation of a Lateral Flow Immunoassay Test Kit for Dual Detection of Casein and β-Lactoglobulin Residues.

    Science.gov (United States)

    Masiri, Jongkit; Barrios-Lopez, Brianda; Benoit, Lora; Tamayo, Joshua; Day, Jeffrey; Nadala, Cesar; Sung, Shao-Lei; Samadpour, Mansour

    2016-03-01

    Allergies to cow's milk are very common and can present as life-threatening anaphylaxis. Consequently, food labeling legislation mandates that foods containing milk residues, including casein and/or β-lactoglobulin, provide an indication of such on the product label. Because contamination with either component independent of the other can occur during food manufacturing, effective allergen management measures for containment of milk residues necessitates the use of dual screening methods. To assist the food industry in improving food safety practices, we have developed a rapid lateral flow immunoassay test kit that reliably reports both residues down to 0.01 μg per swab and 0.1 ppm of protein for foods. The assay utilizes both sandwich and competitive format test lines and is specific for bovine milk residues. Selectivity testing using a panel of matrices with potentially interfering substances, including commonly used sanitizing agents, indicated reduction in the limit of detection by one-to fourfold. With food, residues were easily detected in all cow's milk-based foods tested, but goat and sheep milk residues were not detected. Specificity analysis revealed no cross-reactivity with common commodities, with the exception of kidney beans when present at high concentrations (> 1%). The development of a highly sensitive and rapid test method capable of detecting trace amounts of casein and/or β-lactoglobulin should aid food manufacturers and regulatory agencies in monitoring for milk allergens in environmental and food samples.

  20. Growth-dependent modulation of casein kinase II and its substrate nucleolin in primary human cell cultures and HeLa cells

    DEFF Research Database (Denmark)

    Schneider, H R; Issinger, O G

    1989-01-01

    We have previously provided evidence that casein kinase II (CKII) and its substrate nucleolin increase concomitantly during certain development stages during embryogenesis (Schneider et al., Eur. J. Biochem. 161, 733-738). We now show that during normal growth of primary cell cultures and HeLa...

  1. Characterization of enzymatically induced aggregation of casein micelles in natural concentration by in situ static light scattering and ultra low shear viscosimetry

    DEFF Research Database (Denmark)

    Lehner, D.; Worning, Peder; G, Fritz

    1999-01-01

    The aggregation of casein micelles in undiluted skim milk after the addition of chymosin was studied bystatic light scattering and ultra low shear viscometry. The static light scattering measurements were madewith two different sample thicknesses, 72 and 16 mum. The scattering data were analyzed...

  2. Properties of acid casein gels made by acidification with Glucono-δ-lactone. 2. Syneresis, permeability and micro-structural properties

    NARCIS (Netherlands)

    Lucey, J.A.; Vliet, van T.; Grolle, K.; Geurts, T.; Walstra, P.

    1997-01-01

    Syneresis of casein gels made by acidification with glucono-δ-lactone (GDL) was studied in relation to gel structure as derived from permeametry and confocal scanning laser microscopy (CSLM). Gels made at 40 °C exhibited ‘spontaneous syneresis’ with wheying-off almost immediately after gelation, whi

  3. The milk protein α-casein functions as a tumor suppressor via activation of STAT1 signaling, effectively preventing breast cancer tumor growth and metastasis

    Science.gov (United States)

    Bonuccelli, Gloria; Castello-Cros, Remedios; Capozza, Franco; Martinez-Outschoorn, Ubaldo E.; Lin, Zhao; Tsirigos, Aristotelis; Xuanmao, Jiao; Whitaker-Menezes, Diana; Howell, Anthony; Lisanti, Michael P.; Sotgia, Federica

    2012-01-01

    Here, we identified the milk protein α-casein as a novel suppressor of tumor growth and metastasis. Briefly, Met-1 mammary tumor cells expressing α-casein showed a ~5-fold reduction in tumor growth and a near 10-fold decrease in experimental metastasis. To identify the molecular mechanism(s), we performed genome-wide transcriptional profiling. Interestingly, our results show that α-casein upregulates gene transcripts associated with interferon/STAT1 signaling and downregulates genes associated with “stemness.” These findings were validated by immunoblot and FACS analysis, which showed the upregulation and hyperactivation of STAT1 and a decrease in the number of CD44(+) “cancer stem cells.” These gene signatures were also able to predict clinical outcome in human breast cancer patients. Thus, we conclude that a lactation-based therapeutic strategy using recombinant α-casein would provide a more natural and non-toxic approach to the development of novel anticancer therapies. PMID:23047602

  4. An evaluation of casein hydrolyzate in combination with antibiotic for bacterial cure and subsequent increase in milk yield in dairy cows

    Directory of Open Access Journals (Sweden)

    Silanikove Nissim

    2011-01-01

    Full Text Available Abstract Background A 3-yr study examined whether prepartum treatment with casein hydrolyzate in combination with antibiotic, as routinely used in Israel for dry cow therapy, improved bacterial cure and increased milk yield in subsequent lactations in comparison with treatment with antibiotic alone. The vast majority of bacterial isolates in samples collected prior to drying-off comprised coagulase-negative staphylococci, mostly as Staph. chromogenes. Results Bacterial cure associated with the combined treatment was 73.8% in cows, significantly higher than the 51.7% cure recorded when cows were treated only with antibiotic. During the study, the annual milk yield of non-casein hydrolyzate treated and treated control cows increased at ~2% per year, which is consistent with the national annual increase attributed to genetic selection. In cows treated with casein hydrolyzate the increase was 9% (above the 2% expected in the first lactation after the treatment, and 6.3% (above the 4% expected for 2 years in the second lactation after treatment. These increases were significantly higher than those in the controls and those expected through genetic improvement. Conclusions Treatment with casein hydrolyzate at dry-off was shown to be a viable mean to eliminate existing environmental bacterial infection, and to improve milk yield in the next lactation.

  5. Integration of prolactin and glucocorticoid signaling at the beta-casein promoter and enhancer by ordered recruitment of specific transcription factors and chromatin modifiers

    Science.gov (United States)

    Lactogenic hormone regulation of beta-casein gene expression in mammary epithelial cells provides an excellent system in which to perform kinetic studies of chromatin remodeling and transcriptional activation. Using HC11 cells as a model, we have investigated the effects of prolactin and glucocortic...

  6. Casein protein results in higher prandial and exercise induced whole body protein anabolism than whey protein in chronic obstructive pulmonary disease.

    Science.gov (United States)

    Engelen, Mariëlle P K J; Rutten, Erica P A; De Castro, Carmen L N; Wouters, Emiel F M; Schols, Annemie M W J; Deutz, Nicolaas E P

    2012-09-01

    Exercise is known to improve physical functioning and health status in Chronic Obstructive Pulmonary Disease (COPD). Recently, disturbances in protein turnover and amino acid kinetics have been observed after exercise in COPD. The objective was to investigate which dairy protein is able to positively influence the protein metabolic response to exercise in COPD. 8 COPD patients and 8 healthy subjects performed a cycle test on two days while ingesting casein or whey protein. Whole body protein breakdown (WbPB), synthesis (WbPS), splanchnic amino acid extraction (SPE), and NetWbPS (=WbPS-WbPB) were measured using stable isotope methodology during 20 min of exercise (at 50% peak work load of COPD group). The controls performed a second exercise test at the same relative workload. Exercise was followed by 1 h of recovery. In the healthy group, WbPS, SPE, and NetPS were higher during casein than during whey feeding (Pexercise, independent of exercise intensity (PCOPD due to lower WbPB (Pexercise during casein and whey feeding in COPD (Pexercise were higher in COPD (Pexercise, lower NetPS values were found independent of protein type in both groups. Casein resulted in more protein anabolism than whey protein which was maintained during and following exercise in COPD. Optimizing protein intake might be of importance for muscle maintenance during daily physical activities in COPD.

  7. Potential mechanisms explaining why hydrolyzed casein-based diets outclass single amino acid-based diets in the prevention of autoimmune diabetes in diabetes-prone BB rats

    NARCIS (Netherlands)

    Visser, J. T. J.; Bos, N. A.; Harthoorn, L. F.; Stellaard, F.; Beijer-Liefers, S.; Rozing, J.; van Tol, E. A. F.

    2012-01-01

    Background It remains controversial whether avoidance of dietary diabetogenic triggers, such as cow's milk proteins, can prevent type 1 diabetes in genetically susceptible individuals. Here, different extensive casein hydrolysates (HC) and single amino acid (AA) formulations were tested for their ef

  8. Setting up of a liquid chromatography-high resolution tandem mass spectrometry method for the detection of caseins in food. A comparison with ELISA method

    Directory of Open Access Journals (Sweden)

    Daniela Gastaldi

    2013-06-01

    Full Text Available Determination of caseins in food matrices is usually performed by using the competitiveenzyme- linked immunosorbent assay (ELISA technique. However such a technique suffers from a number of limitations. Among these, the applicability to a narrow concentration range, a non linear (logarithmic response, a non-negligible cross-reactivity and a high cost per kit. At the time of the completion of this study, in case of ELISA positive feedback, there was poor availability in the literature of finding reliable instrumental methods able to determine both qualitatively and quantitatively this class of substances. In the present study, a liquid chromatography-high resolution tandem mass spectrometry (HPLC-HRMS/MS instrumental method was developed with a high resolution mass spectrometer (Orbitrap. Real samples of sausages in which caseins were detected by ELISA technique were analysed. A casein-free sample of ham was used as a blank. The analytical characteristics of the instrumental method were compared with those of a commercial ELISA test, declared specific for α- and β-casein.

  9. Extensively hydrolysed casein formula supplemented with Lactobacillus rhamnosus GG maintains hypoallergenic status : randomised double-blind, placebo-controlled crossover trial

    NARCIS (Netherlands)

    Muraro, Antonella; Hoekstra, Maarten O.; Meijer, Yolanda; Lifschitz, Carlos; Wampler, Jennifer L.; Harris, Cheryl; Scalabrin, Deolinda M. F.

    2012-01-01

    Objective: To evaluate the hypoallergenicity of an extensively hydrolysed (EH) casein formula supplemented with Lactobacillus rhamnosus GG (LGG). Design: A prospective, randomised, double-blind, placebo-controlled crossover trial. Setting: Two study sites in Italy and The Netherlands. Study particip

  10. Effect of calcium chelators on heat coagulation and heat-induced changes of concentrated micellar casein solutions: The role of calcium-ion activity and micellar integrity

    NARCIS (Netherlands)

    Kort, de E.J.P.; Minor, M.; Snoeren, T.A.L.; Hooijdonk, van A.C.M.; Linden, van der E.

    2012-01-01

    There is general consensus that calcium chelators enhance heat stability in milk. However, they increase the heat stability to considerably different extents. For this reason, the effect of various calcium chelators on heat coagulation and heat-induced changes of concentrated micellar casein solutio

  11. Transport of β-Casein-derived Peptides by the Oligopeptide Transport System Is a Crucial Step in the Proteolytic Pathway of Lactococcus lactis

    NARCIS (Netherlands)

    Kunji, E.R S; Hagting, A; de Vries, C.J.; Juillard, V.; Haandrikman, A.J; Poolman, B.; Konings, W.N

    1995-01-01

    In the proteolytic pathway of Lactococcus lactis, milk proteins (caseins) are hydrolyzed extracellularly to oligopeptides by the proteinase (PrtP). The fate of these peptides, i.e. extracellular hydrolysis followed by amino acid uptake or transport followed by intracellular hydrolysis, has been addr

  12. 酪蛋白凝固与乳纤维蛋白溶酶活性的关系%Relationship between casein coagulation and the activity of plasmin

    Institute of Scientific and Technical Information of China (English)

    白英; 刘彩艳

    2012-01-01

    采用分光光度计和SDS-PAGE电泳的方法,以鲜乳为原料,分别对酸沉,酶凝和钙凝的酪蛋白胶粒中的纤溶酶活性进行测定,对酪蛋白凝固与乳纤维蛋白溶酶活性的关系进行研究.结果表明,酸沉酪蛋白纤溶酶活性及总纤溶酶活性最高,分别为212.00 U/mL和250.00 U/mL,酶凝次之,Ca2+凝酪蛋白纤溶酶活性最低.%Through activity assay of casein micelle-associated plasmin by spectrophotometer and SDS-PAGE, relationship between the casein coagulation and activity of plasmin were studied-Results showed that the activity of acid precipitate casein micelle-associated plasmin was highest. The activity of plasmin was 212.00 U/mL. The total activity of plasmin was 250.00 U/mL. Rennin coagulation casein micelle-associated plasmin and the total activity were both lowest.

  13. The autophosphorylation and p34cdc2 phosphorylation sites of casein kinase-2 beta-subunit are not essential for reconstituting the fully-active heterotetrameric holoenzyme

    DEFF Research Database (Denmark)

    Meggio, F; Boldyreff, B; Issinger, O G;

    1993-01-01

    Two mutants of human casein kinase-2 beta-subunit with short deletions at either their amino (delta 1-4) or carboxy (delta 209-215) terminal side have been created that have lost the capability to undergo autophosphorylation and p34cdc2 mediated phosphorylation, respectively. Both mutants give rise...

  14. An extensively hydrolysed casein-based formula for infants with cows' milk protein allergy : tolerance/hypo-allergenicity and growth catch-up

    NARCIS (Netherlands)

    Dupont, Christophe; Hol, Jeroen; Nieuwenhuis, Edward E. S.

    2015-01-01

    Children with cows' milk protein allergy (CMPA) are at risk of insufficient length and weight gain, and the nutritional efficacy of hypo-allergenic formulas should be carefully assessed. In 2008, a trial assessed the impact of probiotic supplementation of an extensively hydrolysed casein-based formu

  15. Effects of casein phosphopeptide amorphous calcium fluoride phosphate paste on white spot lesions and dental plaque after orthodontic treatment: a 3-month follow-up

    NARCIS (Netherlands)

    Beerens, M.W.; van der Veen, M.H.; van Beek, H.; ten Cate, J.M.

    2010-01-01

    The effects of casein phosphopeptide amorphous calcium fluoride phosphate (CPP-ACFP) paste vs. control paste on the remineralization of white spot caries lesions and on plaque composition were tested in a double-blind prospective randomized clinical trial. Fifty-four orthodontic patients, with multi

  16. Na+/glucose co-transporter abundance and activity in the small intestine of lambs: enhancement by abomasal infusion of casein.

    Science.gov (United States)

    Mabjeesh, Sameer J; Guy, Dafna; Sklan, David

    2003-05-01

    The purpose of the present study was to determine the effect of abomasal casein infusion on glucose uptake and abundance of the Na+/glucose co-transporter (SGLT1) 1 in the ovine small intestine. Lambs (body weight 35 (sem 1.0) kg) were surgically fitted with abomasal infusion catheters and were fed diets containing equal portions of wheat hay and cracked maize. Lambs were infused with either 500 g water/d or with 500 g water containing 35 g casein/d. The infusion period lasted 10 d, after which lambs were killed, exsanguinated and eviscerated. Brush border membrane vesicles (BBMV) were prepared using mucosa from different small intestinal regions. Intake and total tract digestibility of nutrients were similar between treatments and averaged 1134, 1142 and 486 g/d and 67, 70, and 94 % for DM, organic matter and non-structural carbohydrates respectively. Crude protein (Nx6.25) digestibility was 15 % greater in the casein-infused than control lambs. Glucose uptake to BBMV ranged from 101 to 337 pmol/mg protein per s along the small intestine and was greatest in the mid-section of the small intestine. In the mid-jejunum, glucose uptake was greater (Pinfused with casein and averaged 120 pmol/mg protein per s compared with 68 pmol/mg protein per s in the control group. SGLT1 affinity was similar between treatments and averaged 104 microm in the different segments of the small intestine of lambs. However, lambs infused with casein exhibited similar values along the small intestine and affinity averaged 106 microm, while in the control group a greater affinity (85 microm) was measured in the mid-jejunum. SGLT1 protein abundance was correlated with glucose uptake in the BBMV in the casein-treated lambs, but not in the control group. These results suggest that glucose uptake along the small intestine of lambs is influenced by casein or its derivatives in the small intestine via SGLT1 affinity and activity at the brush border membrane, and that SGLT1 activity may be regulated

  17. 牦牛乳酪蛋白胶束琥珀酰化修饰研究%Study on succinylated modification of yak casein micelle

    Institute of Scientific and Technical Information of China (English)

    杨敏; 梁琪; 杨继涛; 张媛

    2013-01-01

    以琥珀酸酐为酰化试剂,牦牛乳酪蛋白为原料,对其进行了酰化修饰.系统研究了多种因素对酰化程度的影响,采用响应面法优化了修饰工艺,研究了酪蛋白乳化性变化.结果显示,牦牛乳酪蛋白胶束琥珀酰化修饰最佳条件为琥珀酸酐与酪蛋白配比0.6∶1 (g/g),温度42℃,反应时间49min,pH8.8,酰化程度为86.01%.修饰后,牦牛乳酪蛋白的乳化稳定性和乳化活性分别提高了161.64%和98.54%.酪蛋白酰胺化修饰反应条件温和,易调节,修饰程度高,修饰酪蛋白的乳化性显著改善.该研究可为牛乳酪蛋白的酰化改性提供参考依据.%The yak casein micelles were modified using succinic anhydride as the reagent.The influences of several factors on the modified degree were studied,the process of succinylated modification was optimized by response surface method and the emulsifying properties were experimented.The results showed that the optimal conditions of succinylation were the ratio of succinic anhydride to casein at 0.6∶1 (g/g),temperature of 42℃,reaction time of 49min,pH of 8.8.Under this condition,the modified degree was 86.01%.By succinylation,the emulsifying activity index and emulsion stability index of yak casein increased with the percentage change relative to original casein of 161.64% and 98.54%,respectively.The conditions of succinylated modification on casein were mild and easy to adjust.The degree of modification was higher and the emulsifying properties of modified casein were improved significantly.The results could provide references for the chemical modification of casein.

  18. 凝乳酶水解酪蛋白生产酪蛋白糖巨肽工艺条件的研究%Study on technology conditions of chymosin hydrolyzing casein to produce casein glycomacropeptide

    Institute of Scientific and Technical Information of China (English)

    张秀媛; 袁永俊

    2008-01-01

    酪蛋白糖巨肽(casein glycomacropeptide,简称CGMP)是K-酪蛋白经酶解后生成的一类舍有糖链的多肽,具有许多功能特性.本文研究了凝乳酶水解酪蛋白生产CGMP的工艺条件,通过正交实验得到最佳工艺条件是底物浓度10mg/mL、酶的添加量为0.6%、酶解时间为2.5h.唾液酸回收率为80.7%,蛋白质回收率为3.03%,糖基化程度(唾液酸/蛋白质)为77.6μg/mg.

  19. Effect of dry-heat treatment on the structure and properties of AN-g-Casein fibers%干热处理对 AN-g-Casein 纤维结构和性能的影响

    Institute of Scientific and Technical Information of China (English)

    沈加加; 陈维国; 罗晓菊; 王金玉; 姬树人

    2008-01-01

    为研究干热处理对丙烯腈-酪素接枝共聚(AN-g-Casein)纤维性能和结构的影响,采用扫描电镜、傅里叶红外光谱、X-射线衍射等进行分析.结果表明:在140℃以下干热处理时,纱线收缩率较小,白度变化较小,且强力增加;140℃是丙烯腈-酪素接枝共聚纤维安全干热加工的临界温度;干热处理温度超过140℃,丙烯腈-酪素接枝共聚纤维结构发生变化,纤维开始扭曲变形,泛黄加剧.结晶度下降.

  20. The role of casein-specific IgA and TGF-β in children with Food Protein-Induced Enterocolitis Syndrome to milk

    Science.gov (United States)

    Konstantinou, George N.; Bencharitiwong, Ramon; Grishin, Alexander; Caubet, Jean-Christoph; Bardina, Luda; Sicherer, Scott H.; Sampson, Hugh A.; Nowak-Węgrzyn, Anna

    2014-01-01

    Background Food protein-induced enterocolitis syndrome (FPIES) is a gastrointestinal hypersensitivity disorder with a poorly understood pathophysiology and no biomarkers to aid in diagnosis. Objective To investigate humoral and cellular responses to casein in children with milk-FPIES, including the role of casein-specific (cs) IgA and T-cell mediated TGF-β responses. Patients and methods Thirty-one children previously diagnosed with milk-FPIES were challenged with milk. Twelve age-matched children with FPIES to other foods and 6 milk-tolerant children without a history of FPIES were used as controls. Casein-specific IgE, IgG, IgG4 and IgA were measured in serum and TGF-β levels in supernatants of casein-stimulated PBMCs. Result Twenty-six children with milk-FPIES reacted (active milk-FPIES) and five tolerated milk (milk-FPIES-resolved) during food challenge. All of them had significantly lower levels of csIgG, csIgG4 and csIgA than control children (p-value<0.001). There were no TGF-β responses in supernatants of active milk-FPIES children. Conclusion Children with milk-FPIES have low levels of csIgG, csIgG4 and csIgA. In particular, children with active FPIES to cow’s milk have deficient T-cell mediated TGF-β responses to casein, rendering TGF-β a promising biomarker in identifying children who are likely to experience FPIES reactions to this allergen. Prospective studies are needed to validate these findings, elucidate their role in FPIES pathophysiology and establish the diagnostic utility of TGF-β in milk-induced FPIES. PMID:25283440

  1. Application of soybean casein in coating colors for coated paper%豆酪素在涂布纸涂料中的应用

    Institute of Scientific and Technical Information of China (English)

    黄建林; 孙曼娜

    2015-01-01

    Soybean casein was used to replace a part of styrene-butadiene latex in coating colors, and the inlfuence of soybean casein on the properties of coating colors and coated papers were studied. The results show that the viscosity and moisture-preserving of coating were improved after soybean casein replace a part of styrene-butadiene latex by 1:2. And the glossiness, ink absorbency and printability of coated paper were improved. But the soybean casein effects the IGT surface strength of coated paper adversely. Soybean casein can replaced about 30% styrene-butadiene latex at most, for insuring the properties of coating paper.%研究了涂料配方中豆酪素替代部分羧基丁苯胶乳对铜版纸涂料性能及其成纸指标的影响。结果显示:豆酪素按1∶2的比例替代部分丁苯胶乳后,涂料黏度上升,可以降低增稠剂用量,有利于降低成本;同时涂料保水效果有所改善,有利于上机使用。豆酪素的使用能改善涂布纸的光泽度、油墨吸收性和印刷性能,但豆酪素对涂布纸I GT表面强度有不利影响,当豆酪素用量为2份时,涂布纸I GT表面强度降低了约20%。综合分析,在保证涂布纸主要指标的前提下,豆酪素用量最多为1.5份。

  2. Preparation and acetylated debitterizing of yak milk casein peptides%牦牛乳酪蛋白肽制备及乙酰化脱苦

    Institute of Scientific and Technical Information of China (English)

    纪银莉; 高维东; 宋礼; 何潇; 丁建明; 射小冬

    2013-01-01

    采用碱性蛋白酶对牦牛乳酪蛋白进行水解,得到牦牛乳酪蛋白肽.以醋酸酐为酰化试剂,利用结构修饰的方法对牦牛乳酪蛋白肽进行脱苦研究,探讨醋酸酐添加量、pH对牦牛乳酪蛋白肽酰化度及苦味的影响.结果显示,碱性蛋白酶最佳水解条件为,温度55℃,pH7.0,酶添加量1.25%,反应3h.维持酰化反应pH7以上,产物乙酰化程度最高,醋酸酐的添加量与脱苦效果呈正比,当醋酸酐添加量为40%时,牦牛乳酪蛋白肽酰化产物的苦味基本消失.%Preparation of yak milk casein peptides by hydrolysis of yak milk casein with alkaline protease was studied. Yak milk casein peptides was modified to carry out on the debitterizing research by the acetic anhydride of structural modification.The influence of the adding amount of acetic anhydride and pH on the degree of Yak milk casein peptides acetylation and bitterness was discussed. The result showed that: the enzyme dosage of substrate 1.25% ,pH7.0,55℃ ,3h had the optimum hydrolysis conditions. Maintaining acylation reaction pH above 7, the degree of acetylation were the highest, the acetic anhydride adding amount proportional to the effects of debittering. When acetic anhydride dosage was 40%,the bitterness of yak milk casein peptide acylation product would be disappeared.

  3. Role of xanthine oxidase, lactoperoxidase, and NO in the innate immune system of mammary secretion during active involution in dairy cows: manipulation with casein hydrolyzates.

    Science.gov (United States)

    Silanikove, Nissim; Shapiro, Fira; Shamay, Avi; Leitner, Gabriel

    2005-05-01

    The aims of this study were to test whether xanthine oxidase, lactoperoxidase, and NO are components of the innate immune system of mammary secretion during active involution in dairy cows, and whether the innate immune system is activated by casein hydrolysates. Our laboratory has shown recently that infusion of CNH into mammary glands induced involution and was associated with earlier increases in the concentrations of components of the innate immune system. Intact casein is inactive and served as control. Half of the glands of 8 Holstein cows scheduled for dry off (approximately 60 days before parturition) were injected for 3 days with a single dose of casein hydrolyzates and the contralateral glands with a single dose of intact casein with the same concentration. Involution elicited marked increases in xanthine oxidase and lactoperoxidase activities, and accumulation of urate and nitrate. NO and H(2)O(2) were constantly produced in the mammary gland secretion. Nitrite formed either by autooxidation of NO or by conversion of nitrate to nitrite by xanthine oxidase was converted into the powerful nitric dioxide radical by lactoperoxidase and H(2)O(2) that is derived from the metabolism of xanthine oxidase. Nitric dioxide is most likely responsible for the formation of nitrosothiols on thiol-bearing groups, which allows an extended NO presence in mammary secretion. Nitrite is effectively converted to nitrate, which accumulated in the range of approximately 25 microM -1 mM from the start of the experiment to the complete involution of glands. The mammary secretion in all glands was bactericidal and bacteriostatic during established involution, and this appeared sooner and more acutely in glands treated with casein hydrolyzates, within 8 to 24 h. It is concluded that xanthine oxidase, lactoperoxidase, and NO are components of the mammary innate immune system that form bactericidal and bacteriostatic activities in mammary secretions. The innate immune system play a

  4. Progress of effect on bovine casein micelles during heat treatment%热处理对牛乳酪蛋白胶束结构影响的研究进展

    Institute of Scientific and Technical Information of China (English)

    杨楠; 梁琪; 甘伯中; 杨敏; 张炎

    2012-01-01

    This paper review the effects on the casein's internal force in milk, the monomers of the casein and micelle structure in heat treatment are mainly summarized. The difference of the temperature and Processing time in heat treatment lead to the change of the hydrophobic interaction of the casein and the disulfide bond, the difference of the dissociation degree and structure of the monomers forming the casein (α,- casein, β-casein, k-casein) and the change of the size of casein micelles, together with the change of micelle intention, which is of great significance in directing the application of milk casein and the study of the whole micellar structure in heat treatment.%概述了热处理过程中对牛乳中酪蛋白内部作用力、酪蛋白各个单体以及胶束结构的影响.指出热处理的温度和处理时间的不同,导致酪蛋白的疏水作用及二硫键的变化、组成酪蛋白胶束的各个单体(α-酪蛋白、β-酪蛋白、κ-酪蛋白)离解程度及结构的差异、酪蛋白胶束尺寸及胶束间作用力的改变.这对于牛乳酪蛋白的应用和整个胶束结构在热处理过程中的研究具有指导意义.

  5. Effect of increased intake of skimmed milk, casein, whey or water on body composition and leptin in overweight adolescents

    DEFF Research Database (Denmark)

    Larnkjær, Anni; Arnberg, Karina; Michaelsen, Kim F.

    2015-01-01

    and leptin in overweight adolescents. METHODS: Subjects (n = 193) aged 12-15 years were randomized to drink 1 L d(-1) of skimmed milk, whey, casein (all milk-based drinks 35 g protein L(-1) ) or water for 12 weeks. Twenty participants dropped out. A pre-test control group of 32 adolescents was examined 12......BACKGROUNDS: Dairy proteins may support muscle protein synthesis and improve satiety in adults. However, there are limited studies using exact measures of body composition, especially in adolescents. OBJECTIVES: This study investigates the effect of milk proteins and water on body composition...... weeks before start of intervention. Outcomes included leptin and dual-energy X-ray absorptiometry scanning. The effects of the milk-based drinks on body composition and leptin were compared with baseline, pre-test control and water. RESULTS: Lean mass index (LMI) increased compared to baseline (all 95...

  6. Influence of protein type on oxidation and digestibility of fish oil-in-water emulsions: gliadin, caseinate, and whey protein.

    Science.gov (United States)

    Qiu, Chaoying; Zhao, Mouming; Decker, Eric Andrew; McClements, David Julian

    2015-05-15

    The influence of three surface-active proteins on the oxidative stability and lipase digestibility of emulsified ω-3 oils was examined: deamidated wheat gliadin (gliadin); sodium caseinate (CN); whey protein isolate (WPI). Gliadin and WPI were more effective at inhibiting lipid oxidation (hydroperoxides and TBARS) of fish oil-in-water emulsions than CN. Protein oxidation during storage was determined by measuring the loss of tryptophan fluorescence. The CN-emulsions exhibited the highest loss of tryptophan fluorescence during aging, as well as the highest amount of lipid oxidation. Potential reasons for the differences in oxidative stability of the emulsions with different proteins include differences in interfacial film thickness, protein chelating ability, and antioxidant amino acids profiles. During in vitro digestion, gliadin-stabilized emulsions had the lowest digestion rate of the three proteins. These results have important implications for using proteins to fabricate emulsion-based delivery systems for ω-3 oils.

  7. Optimization of Microencapsulation of Fish Oil with Gum Arabic/Casein/Beta-Cyclodextrin Mixtures by Spray Drying.

    Science.gov (United States)

    Li, Junjie; Xiong, Shanbai; Wang, Fang; Regenstein, Joe M; Liu, Ru

    2015-07-01

    Fish oil was encapsulated with gum arabic/casein/beta-cyclodextrin mixtures using spray drying. The processing parameters (solids concentration of the barrier solutions, ratio of oil to barrier materials, emulsifying temperature, and air inlet temperature) were optimized based on emulsion viscosity, emulsion stability, encapsulation efficiency, and yield. A suitable viscosity and high emulsion stability could increase encapsulation efficiency and yield. Encapsulation efficiency and yield were significantly affected by all the 4 parameters. Based on the results of orthogonal experiments, encapsulation efficiency and yield reached a maximum of 79.6% and 55.6%, respectively, at the optimal condition: solids concentration of 35%, ratios of oil to barrier materials of 3:7, emulsifying temperature of 55 °C, and air inlet temperature of 220 °C. Scanning electron microscopy analysis showed that fish oil microcapsules were nearly spherical with a smooth surface with droplet size ranging from 1 to 10 μm.

  8. RNA helicase DDX3 is a regulatory subunit of casein kinase 1 in Wnt-β-catenin signaling.

    Science.gov (United States)

    Cruciat, Cristina-Maria; Dolde, Christine; de Groot, Reinoud E A; Ohkawara, Bisei; Reinhard, Carmen; Korswagen, Hendrik C; Niehrs, Christof

    2013-03-22

    Casein kinase 1 (CK1) members play key roles in numerous biological processes. They are considered "rogue" kinases, because their enzymatic activity appears unregulated. Contrary to this notion, we have identified the DEAD-box RNA helicase DDX3 as a regulator of the Wnt-β-catenin network, where it acts as a regulatory subunit of CK1ε: In a Wnt-dependent manner, DDX3 binds CK1ε and directly stimulates its kinase activity, and promotes phosphorylation of the scaffold protein dishevelled. DDX3 is required for Wnt-β-catenin signaling in mammalian cells and during Xenopus and Caenorhabditis elegans development. The results also suggest that the kinase-stimulatory function extends to other DDX and CK1 members, opening fresh perspectives for one of the longest-studied protein kinase families.

  9. Comparison of the Function and Conformation of Human β-Casein and Bovineβ-Casein by Spectroscopic Study%荧光、紫外和红外光谱分析人乳和牛乳β-酪蛋白的功能和构象差异

    Institute of Scientific and Technical Information of China (English)

    刘微; 李萌; 任皓威; 刘宁

    2014-01-01

    β-casein was the main component of human milk casein ,but the content of β-casein in the bovine milk was less .The difference inβ-casein content of the two samples was one of the reasons why human milk is more digestible than bovine milk . Studying the differences of structure and function in human and bovine milk β-casein can help us develop a new human milk simu-lated infant formula which will be more suitable for the infant gut .The UV spectrophotometer was used to study the solubility , sulfhydryl and emulsification of human milk β-casein and bovine milk β-casein ,Fluorescence spectroscopy and the infrared spec-troscopy were used to study the structural characteristics of human milk β-casein and bovine milk β-casein .The two samples shared a similar isoelectric point (pH 4.0~5.0) ,the solubility of human milk β-casein (10.83% ) was lower than which in bo-vine milkβ-casein (11.83% ) near the pI ,while it was higher when it deviated the pI .The emulsion ability (110~140 m2 ・g -1 ) of human milk β-casein was higher than that in bovine milk β-casein (70~130 m2 ・g -1 ) and surface sulfhydryl group (SH) of two kinds of milk protein were similar [(18.47 ± 0.08)μmol・g -1 and (18.67 ± 0.17)μmol・g -1 ] .The total sulfhydryl group [(47.46 ± 0.23)μmol・g -1 ] in bovine milk β-casein was more than that in human milk β-casein [(26.17 ± 0.12)μmol・g -1 ] . Functional groups in two samples were similar and they both contained beta sheet ,human milkβ-casein had less H-bond and in-ternal hydrophobic than bovine milk β-casein .The results showed that the two samples had similar functional groups ,while hu-man milkβ-casein had much less secondary structure such as α-helix andβ-sheet ,a looser tertiary structure and a better interfa-cial activity .%β-酪蛋白是人乳酪蛋白的主要成分,但它在牛乳中的含量却很小。β-酪蛋白在两者中含量的差异,是人乳比牛乳更易消化的原因之一,研究人乳与牛乳

  10. Differences in Particle Size and Structure of Casein Micelle from Different Milk Sources%3种乳源酪蛋白粒径及胶束结构的差异性

    Institute of Scientific and Technical Information of China (English)

    李子超; 王丽娜; 李昀锴; 徐明芳

    2012-01-01

    The particle distribution of casein and the structure of casein micelle from milk, buffalo milk and goat milk were studied by nanoparticle size analyzer and scanning electron microscopy, respectively. The results suggested that the size distribution of casein and the structure of casein micelle from milk, buffalo milk and goat milk were significantly different. The average casein particle diameter from buffalo milk was 182.3 nm. The connected casein particles formed slender micelles, and the micelles cross- linked into a network structure. The average casein particle diameter from milk was 207.4 nm, and the connected casein particles formed thick micelles. The average casein particle diameter from goat milk was 173.8 nm, and the connected casein particles formed short casein micelles but the miceUes can not be cross-linked into a network structure.%通过纳米粒度分析仪和扫描电子显微镜,分别对水牛乳、牛乳及羊乳中的酪蛋白颗粒直径大小分布情况及酪蛋白胶束结构进行研究。结果表明:水牛乳、牛乳及羊乳中酪蛋白的粒径分布及胶束结构方面存在明显的差异。水牛乳酪蛋白平均颗粒直径为182.3nm,酪蛋白颗粒互相连接成较细长的胶束,胶束之间交联成网络状;牛乳酪蛋白平均颗粒直径为207.4nm,酪蛋白颗粒聚集成直径较大的胶束;羊乳酪蛋白平均颗粒直径为173.8nm,酪蛋白颗粒仪能够形成较短的胶束,也不能交联成网络状。

  11. The effects of intraruminal infusions of urea, casein, glucose syrup and a mixture of casein and glucose syrup on nitrogen digestion in the rumen of cattle receiving grass-silage diets.

    Science.gov (United States)

    Rooke, J A; Lee, N H; Armstrong, D G

    1987-01-01

    In an incomplete 5 X 5 Latin square experiment, four cattle were given grass silage in two meals per d to satisfy 1.15 maintenance energy requirements. In addition, water or casein (21 g nitrogen and 0.17 kg organic matter (OM)/d) or urea (U; 28 g N/d) or a glucose syrup (G; 0.87 kg OM/d) or casein and glucose syrup (CG; 17 g N and 0.93 kg OM/d) were infused intraruminally at a constant rate. A 24 h collection of duodenal digesta was made using chromic oxide for flow estimation and 35S as a marker of microbial N entering the small intestine. Samples of rumen fluid were also taken for estimation of rumen pH, and concentrations of ammonia-N and volatile fatty acids. The intraruminal infusions had no significant effects on rumen pH, concentrations of volatile fatty acids or their molar proportions. Infusion of either C or U significantly (P less than 0.05) increased rumen NH3-N concentrations whereas infusions of either G or CG lowered rumen NH3-N concentrations. Infusions of C or U had no significant effect on the quantities of OM, acid-detergent fibre (ADF) or N constituents which entered the small intestine. Infusions of G or CG increased the quantities of OM (G P less than 0.05, CG P less than 0.01), ADF (CG P less than 0.05), non-NH3-N (G P less than 0.05, CG P less than 0.01), amino acid N (G P less than 0.05, CG P less than 0.01) and microbial N (G P less than 0.05, CG P less than 0.01) which entered the small intestine. The efficiency of rumen microbial N synthesis was unchanged by the infusion of C, U or G (P greater than 0.05) but increased significantly (P less than 0.05) when CG were infused.

  12. Differential effects of protein quality on postprandial lipemia in response to a fat-rich meal in type 2 diabetes: comparison of whey, casein, gluten, and cod protein

    DEFF Research Database (Denmark)

    Mortensen, Lene S; Hartvigsen, Merete L; Brader, Lea J

    2009-01-01

    : The objective was to compare the effects of the proteins casein, whey, cod, and gluten on postprandial lipid and incretin responses to a high-fat meal in persons with type 2 diabetes. DESIGN: A crossover study was conducted in 12 patients with type 2 diabetes. Blood samples were collected over 8 h after...... ingestion of a test meal containing 100 g butter and 45 g carbohydrate in combination with 45 g casein (Cas-meal), whey (Whe-meal), cod (Cod-meal), or gluten (Glu-meal). We measured plasma concentrations of triglycerides, retinyl palmitate (RP), free fatty acids, insulin, glucose, glucagon, glucagon......, glucagon-like peptide 1, and glucose-dependent insulinotropic peptide responses. CONCLUSION: The data suggest that as a supplement to a fat-rich meal in patients with type 2 diabetes, whey protein seems to outperform other proteins in terms of postprandial lipemia improvement, possibly because...

  13. ANALYSIS OF POLYMORPHISM OF BETA CASEIN OF SLOVAK PINZGAU CATTLE BY PCR-RFLP FOR ALLELS A1 AND A2

    Directory of Open Access Journals (Sweden)

    MARTINA MILUCHOVÁ

    2013-07-01

    Full Text Available The work was oriented to identification of -casein gene polymorphism and analysis of genotype structure in population of Slovak Pinzgau cattle. The material involved 89 cattle. Bovine genomic DNA was isolated by fenol-chlorophorm deprotenization and ethanol precipitation and used in order to estimate  - casein genotypes by means of PCR-RFLP method. The PCR products were digested with DdeI restriction enzyme. In the population included in the study there were homozygote genotype A1A1 (27 animals, heterozygote genotype A1A2 (46 animals and homozygote genotype A2A2 (16 animals. In the total population of cattle heterozygotes A1A2 – 0.5168 were the most frequent, while homozygotes A2A2 – 0.1798 were the least frequent ones. This suggests a slight superiority of allele A1– 0.5618.

  14. Influence of Casein-Phospholipid Combinations as Emulsifier on the Physical and Oxidative Stability of Fish Oil-in-Water Emulsions

    DEFF Research Database (Denmark)

    García Moreno, Pedro Jesús; Horn, Anna Frisenfeldt; Jacobsen, Charlotte

    2014-01-01

    The objective of this study was to investigate the influence of casein (0.3% w/w) and phospholipid (0.5% w/w) emulsifier combinations on the physical and oxidative stability of 10% fish oil-in-water emulsions at pH 7. For that purpose, three phospholipids were evaluated, namely, lecithin (LC......), phosphatidylcholine (PC), and phosphatidylethanolamine (PE). The emulsion stabilized with LC showed the best physical stability having the most negative zeta potential and the lowest mean droplet size. In addition, this emulsion was also the least oxidized in terms of peroxide value and concentration of the volatile...... oxidation product 1-penten-3-ol. This finding is not explained by the antioxidant activity of LC because it showed similar DPPH scavenging activity and lower metal chelating activity than the other phospholipids. Therefore, these results suggested that other factors such as the combination of casein...

  15. Effect of alphas1-casein ( CSN1S1) genotype on milk CSN1S1 content in Malagueña and Murciano-Granadina goats.

    Science.gov (United States)

    Caravaca, Francisco; Amills, Marcel; Jordana, Jordi; Angiolillo, Antonella; Agüera, Pastora; Aranda, Cristina; Menéndez-Buxadera, Alberto; Sánchez, Alfonso; Carrizosa, Juan; Urrutia, Baltasar; Sànchez, Armand; Serradilla, Juan Manuel

    2008-11-01

    There is substantial evidence showing that the polymorphism of the goat alphas1-casein (CSN1S1) gene has a major effect on milk protein, casein and fat content as well as on cheese yield. However, its influence on the synthesis rate of CSN1S1 has been less studied, with measurements only available in French breeds. In this article, we have measured milk CSN1S1 content in 89 Malagueña and 138 Murciano-Granadina goats with 305 and 460 phenotypic registers, respectively. In the Malagueña breed, average values of CSN1S1 content estimated for BB, BF, EE and FF genotypes were 6.94+/-0.38, 5.36+/-0.22, 4.58+/-0.13 and 3.98+/-0.27 g/l, respectively, being all significantly different (Pgene polymorphism on the synthesis rate of the corresponding protein.

  16. 牛酪蛋白基因导入大豆的研究%STUDY ON THE INTRODUCTION OF BOVINE CASEIN GENE INTO SOYBEAN PLANTS

    Institute of Scientific and Technical Information of China (English)

    张燕君; 赵双宜; 周同度; 粟翼玟

    2000-01-01

    将带有牛酪蛋白基因casein B的植物表达载体 pAS-2,在大豆自花授粉后,用注射法导入大豆受精子房中.以质粒pAS-2的35S-Casein-Gus片段为模板,随机引物法标记探针,对103株受体植株后代的DNA进行点杂交和Southern杂交,发现其中1株在点杂交和Southern杂交中均呈阳性.证明外源基因已整合到大豆基因组中.

  17. Optimization of preparation of calcium caseinate using response surface methodology%响应面法优化酪蛋白酸钙生产工艺

    Institute of Scientific and Technical Information of China (English)

    葛静微; 纪银莉; 高维东; 张哲敏; 谢小冬

    2013-01-01

    以食品级干酪素为原料,以制备的酪蛋白酸钙中钙含量为指标,采用单因素实验、中心组合(Box-Benhnken)试验设计与响应曲面分析法,研究了酪蛋白酸钙的生产工艺.在单因素实验的基础上采用3因素3水平的响应曲面分析法,以酪蛋白酸钙中钙含量为指标,考察溶液pH、溶液浓度与Ca (OH)2添加量对酪蛋白酸钙制备的影响,建立了酪蛋白酸钙制备中钙含量与各影响因子的回归方程,确定了最佳工艺条件.结果表明:最佳制备工艺为溶液pH值为7.16、料液浓度为5.97%、Ca(OH)2添加量为1.716%,在此条件下制备的酪蛋白酸钙中钙含量为1.639%,与预测值1.642%相差不显著.该工艺酪蛋白酸钙得率高,所得产品含钙量较高,产品具有较好的品质.%Food grade casein was used as a raw material,manufacturing technique of calcium caseinate was studied by single factor test and Box-Benhnken design combined with response surface methodology.Calcium content in calcium caseinate was the index.Single factor method and response surface methodology with 3 factors and 3 levels were applied to optimize parameters such as pH,concentration and Ca(OH) 2 amount on affecting calcium content in calcium caseinate.The regression equation between the factors and the calcium content in calcium caseinate was established,and the optimum technique was confirmed.Results showed that the optimal preparation technology was:pH 7.16 and 5.97% solution concentration and 1.716% Ca(OH)2 · In the above condition,the calcium content was 1.639%,which was very close to the predicted value of 1.642%.The manufacturing technique of calcium caseinate is an efficient method with high yield of calcium caseinate and high content of calcium,and good quality of calcium caseinate.

  18. 乳源β Casein 125肽的基本特征及促B淋巴细胞增殖作用%Basic characteristics of a human milk-derived peptide β-Casein-125 and its effect on B lymphocyte proliferation

    Institute of Scientific and Technical Information of China (English)

    刘贵友; 万俊; 肖文

    2016-01-01

    The biologic characteristics of β⁃Casein⁃125 peptide were analyzed by Uniprot, SABLE, ProtParam tool and other online databases. The content ofβ⁃Casein⁃125 in colostrum, transition milk and mature milk was mesured by mass spectrometry technology. Furthermore, the effect of β⁃Casein⁃125 peptide in B lymphocyte proliferation was evaluated by MTT assay. The online databases showed that stability coefficient, aliphatic index and grand average of hydropathicity of β⁃Casein⁃125 were 111�43, 111�43 and 0�471, respectively. It indicated that β⁃Casein⁃125 is a hydrophobic stable peptide. The content of β⁃Casein⁃125 was significantly decreased with lactation time, detected by mass spectrometry technology. Moreover, β⁃Casein⁃125 could across the cell membrane of mouse B lymphocytes, and promote their proliferation. β⁃Casein⁃125, a hydrophobic peptide with high stability, could promote lymphocyte proliferation. It was indicated thatβ⁃Casein⁃125 played a critial role in promoting the neonatal immune system maturation.%利用Uniprot、SABLE、ProtParam tool等在线数据库分析β Casein 125肽生物学特征;利用质谱定量技术检测β Casein 125肽在初乳、过渡乳和成熟乳中的含量变化;利用细胞增殖实验方法揭示β Casein 125肽在促进B淋巴细胞增殖中的作用。结果表明:β Casein 125肽的稳定性系数为111�43,脂肪指数和亲水性分别为111�43和0�471,属于疏水性稳定型多肽。质谱定量分析发现:β Casein 125肽含量随泌乳时间变化含量显著降低。β Casein 125肽不仅可以顺利进入小鼠B淋巴细胞,并且可显著促进细胞增殖。β Casein 125肽具有高稳定性和疏水性的特征,可以促进淋巴细胞增殖,提示该肽可能在新生儿免疫系统建立中发挥重要作用。

  19. A longitudinal cross-over study of serum cholesterol and lipoproteins in rabbits fed on semipurified diets containing either casein or soybean protein

    NARCIS (Netherlands)

    Terpstra, A.H.M.; Woodward, C.J.H.; West, C.E.; Boven, van H.G.

    1982-01-01

    1. Two groups, each of six rabbits, were fed on semi-purified diets containing either 400 g casein or 400 g soya-bean protein/kg for 20 d and then the diets of the two groups were crossed-over. 2. Just before the cross-over, the serum cholesterol concentration (mean ± SE) was 3068 ± 592 and 800 ± 14

  20. Verification for the control of kappa-casein gene on milk protein yield of friesian-holstein in dairy central region of West Java

    Directory of Open Access Journals (Sweden)

    A. Anggraeni

    2009-06-01

    Full Text Available Genotipe of BB kappa kasein (ĸ-kasein gene positively influences high milk protein yield. The aim of this research was to verify the use of the к-casein gene as marker of assisted selecion (MAS of high protein yield in domestic Holstein-Friesian (HF cattle. Genotyping blood samples was conducted for lactating cows from BPPT-SP Cikole (82 head and a number of small holders in KPSBU Lembang (190 head. Genotyping the к-casein gene was also conducted for active and non active AI bulls (HF from BIB Lembang (25 head and BBIB Singosari (32 head. Varian genotipes were identified trough DNA migration, whereas frequencies of alleles were calculated by Nei Method (1987. The effects of variant genotypes on protein yield and other milk component yields were studied in lactating cows (56 head in BPPT-SP Cikole and 111 head in KPSBU Lembang by applying Least Square Means (LSM method of the General Linear Model (GLM. Genotyping the ĸ-kasein gene resulted in three genotypes, namely AA, AB and BB, with two alleles, namely A and B. It was identified that a very limited number of lactating cows with BB genotype (0-9%. These cows produced higher protein yield around 3.37-3.84% than that of AA cows, while AB cows produced protein yield in between, though these differences were not statistically significant (P>0,05. In contrast, AA cows tended to produced higher milk fat yield than BB cows. Cows BB and AB seemingly produced higher dry matter, while both specific density and pH were not affected by variant genotypes of the к-casein gene. The results showed that BB genotype of the к-casein gene tended to be quitely consistent in controlling high protein yield, so it would be a good oppurtinity to be used as MAS of milk protein yield in HF domestic.

  1. Influence of casein on flux and passage of serum proteins during microfiltration using polymeric spiral-wound membranes at 50°C.

    Science.gov (United States)

    Zulewska, Justyna; Barbano, David M

    2013-04-01

    Raw milk (approximately 1,800 kg) was separated at 4°C, pasteurized (at 72°C for 16s), and split into 2 batches. One batch (620 kg) was microfiltered (MF) using pilot-scale ceramic uniform transmembrane pressure Membralox membranes (model EP1940GL0.1 μA, 0.1-μm alumina; Pall Corp., East Hills, NY) to produce retentate and permeate. The permeate from the MF uniform transmembrane pressure was casein-free skim milk (CFSM). The CFSM was MF using polymeric spiral-wound (SW) membranes (model FG7838-OS0x-S, 0.3 μm; Parker-Hannifin Corp., Process Advanced Filtration Division, Tell City, IN) at a concentration factor of 3× and temperature of 50°C. Following the processing of CFSM, the second batch of skim milk (1,105 kg) was processed using the same polymeric membranes to determine how casein content in the feed material for MF with polymeric membranes affects the performance of the system. There was little resistance to passage of milk serum proteins (SP) through a 0.3-μm polyvinylidene fluoride (PVDF) SW membrane at 50°C and no detectable increase in hydraulic resistance of the membrane when processing CFSM. Therefore, milk SP contributed little, if any, to fouling of the PVDF membrane. In contrast, when processing skim milk containing a normal concentration of casein, the flux was much lower than when processing CFSM (17.2 vs. 80.2 kg/m(2) per hour, respectively) and the removal of SP from skim milk with a single-pass 3× bleed-and-feed MF system was also much lower than from CFSM (35.2 vs. 59.5% removal, respectively). Thus, when processing skim milk with a PVDF SW membrane, casein was the major protein foulant that increased hydraulic resistance and reduced passage of SP through the membrane.

  2. 消光法快速检测酪蛋白溶液浓度的研究%Study of Light Extinction Method Rapid Detection of Casein Concentration

    Institute of Scientific and Technical Information of China (English)

    周真; 吕廷; 吴玉渠; 秦勇; 丁国超

    2013-01-01

    Aiming at the problem of Kjeldahl determination cant be fastly and directly measured the protein content of milk.Through analysing the theoretical and experimental data,simulation model measured the concentration of the fluid casein by using rapid extinction method was established.Using MATLAB fitting got the curve of the extinction and casein content.The test results show that the establishment of the relational model makes the casein content can be quickly detected.The method has been proved that it can rapidly detect the casein content's feasibility,and provides a theoretical basis for the rapid detection of protein content and on-line testing equipment research.%针对凯氏定氮法无法快速、直接测量牛乳蛋白含量的问题,通过理论和实验数据分析,建立了利用消光法快速测量酪蛋白模拟液浓度的理论模型,利用Matlab拟舍得到了消光度和酪蛋白含量的关系曲线.经研究表明,关系模型的建立使得酪蛋白含量能够被快速检测出来,证明该方法具有快速检测酪蛋白含量的可行性,这就为快速检测蛋白质含量仪器的研制和在线检测提供了理论依据.

  3. Casein kinase 2α regulates multidrug resistance-associated protein 1 function via phosphorylation of Thr249.

    Science.gov (United States)

    Stolarczyk, Elzbieta I; Reiling, Cassandra J; Pickin, Kerry A; Coppage, Ryan; Knecht, Marc R; Paumi, Christian M

    2012-09-01

    We have shown previously that the function of Ycf1p, yeast ortholog of multidrug resistance-associated protein 1 (MRP1), is regulated by yeast casein kinase 2α (Cka1p) via phosphorylation at Ser251. In this study, we explored whether casein kinase 2α (CK2α), the human homolog of Cka1p, regulates MRP1 by phosphorylation at the semiconserved site Thr249. Knockdown of CK2α in MCF7-derived cells expressing MRP1 [MRP1 CK2α(-)] resulted in increased doxorubicin sensitivity. MRP1-dependent transport of leukotriene C(4) and estradiol-17β-d-glucuronide into vesicles derived from MRP1 CK2α(-) cells was decreased compared with MRP1 vesicles. Moreover, mutation of Thr249 to alanine (MRP1-T249A) also resulted in decreased MRP1-dependent transport, whereas a phosphomimicking mutation (MRP1-T249E) led to dramatic increase in MRP1-dependent transport. Studies in tissue culture confirmed these findings, showing increased intracellular doxorubicin accumulation in MRP1 CK2α(-) and MRP1-T249A cells compared with MRP1 cells. Inhibition of CK2 kinase by 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole resulted in increased doxorubicin accumulation in MRP1 cells, but not in MRP1 CK2α(-), MRP1-T249A, or MRP1-T249E cells, suggesting that CK2α regulates MRP1 function via phosphorylation of Thr249. Indeed, CK2α and MRP1 interact physically, and recombinant CK2 phosphorylates MRP1-derived peptide in vitro in a Thr249-dependent manner, whereas knockdown of CK2α results in decreased phosphorylation at MRP1-Thr249. The role of CK2 in regulating MRP1 was confirmed in other cancer cell lines where CK2 inhibition decreased MRP1-mediated efflux of doxorubicin and increased doxorubicin cytotoxicity. This study supports a model in which CK2α potentiates MRP1 function via direct phosphorylation of Thr249.

  4. Composition, somatic cell count and casein fractions of ethanol unstable milks - doi: 10.4025/actascitechnol.v35i1.11481

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Fernandes de Oliveira

    2013-01-01

    Full Text Available This study determined the composition, somatic cell count (SCC and relative percentage of a-S1, a-S2, b and k caseins in ethanol-unstable (UNA and stable bulk milk samples. The sampling plan involved farms that supplied milk to one dairy plant located in the northeast region of São Paulo, Brazil, in May (fall, July (winter, and September (spring 2007. Three hundred thirty-four bulk milk samples within an acceptable range of pH and acidity were included in the study and divided into two groups: a stable milk, when protein precipitation only occurred with 78% ethanol (v/v; and b unstable (UNA milk, when the precipitation occurred with 72% ethanol (v/v. From the total samples analyzed, 77 (23% were unstable in the 72% ethanol (v/v, although they have shown normal pH and acidity, and 41 (12.3% were stable in 78% ethanol (v/v. No differences were found between relative percentages of a and b-casein in UNA or stable milks. However, UNA samples showed higher SCC, as well as lower casein and lactose contents. Results indicated that the high SCC may be involved as a causal factor for the high incidence of UNA milks in the herds studied.  

  5. Improving clarity and stability of skim milk powder dispersions by dissociation of casein micelles at pH 11.0 and acidification with citric acid.

    Science.gov (United States)

    Pan, Kang; Zhong, Qixin

    2013-09-25

    Casein micelles in milk cause turbidity and have poor stability at acidic conditions. In this study, skim milk powder dispersions were alkalized to pH 10.0 or 11.0, corresponding to reduced particle mass. In the following acidification with hydrochloric or citric acid, the re-formation of casein particles was observed. The combination of treatment at pH 11.0 and acidification with citric acid resulted in dispersions with the lowest turbidity and smallest particles, which enabled translucent dispersions at pH 5.5-7.0, corresponding to discrete nanoparticles. The concentration of ionic calcium was lower when acidified with citric acid than hydrochloric acid, corresponding to smaller particles with less negative zeta potential. The pH 11.0 treatment followed by acidification with citric acid also resulted in smaller particles than the simple chelating effects (directly implementing sodium citrate). The produced casein nanoparticles with reduced dimensions can be used for beverage and other novel applications.

  6. A specific pattern of splicing for the horse αS1-Casein mRNA and partial genomic characterization of the relevant locus

    Directory of Open Access Journals (Sweden)

    Guérin Gérard

    2002-07-01

    Full Text Available Abstract Mares' milk has a composition very different from that of cows' milk. It is much more similar to human milk, in particular in its casein fraction. This study reports on the sequence of a 994 bp amplified fragment corresponding to a horse αS1-Casein (αS1-Cn cDNA and its comparison with its caprine, pig, rabbit and human counterparts. The alignment of these sequences revealed a specific pattern of splicing for this horse primary transcript. As in humans, exons 3', 6' and 13' are present whereas exons 5, 13 and 14 are absent in this equine mRNA sequence. BAC clones, screened from a horse BAC library, containing the αS1-Cn gene allowed the mapping of its locus by FISH on equine chromosome 3q22.2-q22.3 which is in agreement with the Zoo-FISH results. Genomic analysis of the αS1-Cn gene showed that the region from the second exon to the last exon is scattered within a nucleotide stretch nearly 15-kb in length which is quite similar in size to its ruminant and rabbit counterparts. The region between αS1- and β-Cn genes, suspected to contain cis-acting elements involved in the expression of all clustered casein genes, is similar in size (ca. 15-kb to the caprine and mouse intergenic region.

  7. Longitudinal analysis of protein glycosylation and β-casein phosphorylation in term and preterm human milk during the first 2 months of lactation.

    Science.gov (United States)

    Molinari, Claire E; Casadio, Ylenia S; Hartmann, Ben T; Arthur, Peter G; Hartmann, Peter E

    2013-07-14

    Human milk proteins provide term and preterm infants with both nutrition and protection. The objective of the present study was to examine longitudinal changes in the protein composition of term and preterm milk during the first 2 months of lactation, focusing on protein phosphorylation and glycosylation. Using gel electrophoresis, the relative concentration and glycosylation status of lactoferrin, secretory Ig A, β-casein, α-lactalbumin, serum albumin, bile salt-stimulated lipase, xanthine oxidoreductase, tenascin and macrophage mannose receptor 1 were measured in milk collected on days 7, 10, 14, 18, 21, 28 and 60 postpartum from preterm mothers (28-32 weeks gestation, n 17). The phosphorylation status of β-casein was also investigated. To determine if these variables differ in term and preterm milk, samples from term mothers (38-41 weeks gestation, n 8) collected on days 7, 14 and 30 of lactation were also analysed. The concentration of the abundant milk proteins decreased during lactation in term and preterm milk (P protein glycosylation was observed, except for the glycoproteins serum albumin and tenascin. The phosphorylation of β-casein varied significantly between term and preterm milk. Further investigation is required to determine whether these modifications affect protein function and are clinically important to preterm infants.

  8. Ethological comparison of the effects of a bovine alpha s1-casein tryptic hydrolysate and diazepam on the behaviour of rats in two models of anxiety.

    Science.gov (United States)

    Violle, Nicolas; Messaoudi, Michaël; Lefranc-Millot, Catherine; Desor, Didier; Nejdi, Amine; Demagny, Benoit; Schroeder, Henri

    2006-07-01

    A bovine alpha s1-casein tryptic hydrolysate was previously demonstrated to display an anxiolytic-like activity in the conditioned defensive burying and in the elevated plus-maze models when i.p. injected. The present study assessed the anxiolytic-like effects of this tryptic hydrolysate after an oral administration in rats faced to the same behavioural situations using diazepam as a reference. In a first experiment, the behavioural effects of the hydrolysate in the conditioned defensive burying test were investigated at doses ranging 5-50 mg/kg. The results showed that the minimal dose required to elicit an anxiolytic-like activity is 15 mg/kg. In a second experiment, the alpha s1-casein tryptic hydrolysate (15 mg/kg, p.o.) was demonstrated to display an anxiolytic-like activity similar to diazepam (3 mg/kg, p.o.) in the conditioned defensive burying test and the elevated plus-maze. However, the ethological analysis of behaviour indicated that this hydrolysate has a different activity compared to diazepam. While diazepam induced a disinhibition state in rats, possibly related to the risk-taking behaviour observed after a benzodiazepine ingestion in humans, the tryptic hydrolysate did not display such a side effect. These results suggest that the mechanism of action of the bovine alpha s1-casein tryptic hydrolysate may differ from that of diazepam.

  9. Cloning and comparative analysis of gene structure in promoter site of alpha-s1 casein gene in Naeinian goat and sheep

    Directory of Open Access Journals (Sweden)

    Mojtaba Najafi

    2014-12-01

    Full Text Available The 5′ end or alpha-S1 casein promoter has a significant role in milk protein gene expression. The understanding of the translation process of alpha-S1 casein mutants will provide us an opportunity to make the best selection in livestock providing more proteins in milk. Blood samples were taken from three hundred of Naeinian goats and sheep, and DNA extraction was done using modified salting out method. Polymerase chain reactions (PCR were carried out using a specific primer pairs for amplification a fragment of 1133 bp from part of 5′-UTR and exon 1 of alpha s1 casein gene. The AluI and HinfI restriction enzyme treatment of all samples provided the same homozygous AA genotype in both species. Subsequently, one sample of each species was selected and cloned, and the final sequences were analyzed by BioEdit, CLC genomic, Mega4 and DNASIS MAX software. Several polymorphisms are recognized between Naeinian goat and sheep that are presented on motif sites. In this research, the interested location, including exon I and a part of 5′, was analyzed, and genetic element comparisons were done between Naeinian goat and sheep. The number and location of probable binding sites can have a crucial role as a result of antagonistic and synergistic effects on gene regulation activities.

  10. Technical note: use of PCR-single-strand conformation polymorphism analysis for detection of bovine beta-casein variants A1, A2, A3, and B.

    Science.gov (United States)

    Barroso, A; Dunner, S; Cañón, J

    1999-10-01

    We have optimized the polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) technique to screen the most frequent variants (A1, A2, A3, and B) of the bovine beta-casein gene. Five partly overlapping PCR products (233, 234, 265, 466, and 498 bp) of Exon VII of the beta-casein gene that encompass the target point mutations were heat-denatured, separated on nondenaturing polyacrylamide gels, and silver-stained. Simultaneous detection of all variants in reference samples of known genotypes (A1A2, A2A2, A1A3, A1B, and A2B) was best achieved on 17% polyacrylamide (100:1 acrylamide:bis-acrylamide ratio) gels with the PCR product of 234 bp. These results were confirmed by sequencing the allele-specific SSCP bands directly excised from polyacrylamide gels. A population of 65 anonymous samples belonging to various breeds was then analyzed twice, without discrepancies in a blind trial. Routine beta-casein genotyping using PCR-SSCP is proposed as a cost-effective, fast, and sensitive technique.

  11. Solvent Binding Analysis and Computational Alanine Scanning of the Bovine Chymosin-Bovine κ-Casein Complex Using Molecular Integral Equation Theory.

    Science.gov (United States)

    Palmer, David S; Sørensen, Jesper; Schiøtt, Birgit; Fedorov, Maxim V

    2013-12-10

    We demonstrate that the relative binding thermodynamics of single-point mutants of a model protein-peptide complex (the bovine chymosin-bovine κ-casein complex) can be calculated accurately and efficiently using molecular integral equation theory. The results are shown to be in good overall agreement with those obtained using implicit continuum solvation models. Unlike the implicit continuum models, however, molecular integral equation theory provides useful information about the distribution of solvent density. We find that experimentally observed water-binding sites on the surface of bovine chymosin can be identified quickly and accurately from the density distribution functions computed by molecular integral equation theory. The bovine chymosin-bovine κ-casein complex is of industrial interest because bovine chymosin is widely used to cleave bovine κ-casein and to initiate milk clotting in the manufacturing of processed dairy products. The results are interpreted in light of the recent discovery that camel chymosin is a more efficient clotting agent than bovine chymosin for bovine milk.

  12. Biotechnological richness of the northeastern semi-arid region: antioxidant activity of casein hydrolysates from Moxotó goat milk (Capra hircus Linnaeus, 1758 obtained by papain action

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    Vilma Sobral Bezerra

    2013-09-01

    Full Text Available This study aimed to identify antioxidant peptides from caprine casein hydrolysates by papain application using MALDI-TOF mass spectrometer, and a 2² full factorial design, with 4 axial points, in order to evaluate kinetic parameters (time and pH effects on the degree of hydrolysis as well as the antioxidant activity of Moxotó goat milk casein peptides. Degree of hydrolysis was determined by total and soluble protein ratio in casein. Antioxidant activity was measured by ABTS method with 2, 2-cation-azinobis (3-ethylbenzothiazoline-6-sulfonic acid. TROLOX was used as standard. Peptide pattern and sequence of antioxidant amino acids were obtained using MALDI-TOF/MS. The highest degree of hydrolysis (28.5% and antioxidant activity (2329.6 mmol.L TROLOX. mg- 1 peptide were observed in the permeate. NENLL, NPWDQVK and LLYQEPVLGPV peptides, detected in the permeate, were pointed as the responsible for antioxidant activity, suggesting their potential application as food supplement and pharmaceutical products.

  13. Optimal Parmeters Study on Processing Casein Phosphopeptide%生物活性肽-酪蛋白磷酸肽(CPP)的研制

    Institute of Scientific and Technical Information of China (English)

    蔡为荣; 薛正莲

    2001-01-01

    摸索了2709碱性蛋白酶水解酪蛋白制备CPP的最佳工艺条件:底物浓度10%、用酶量1500μ/g反应温度45℃、pH10.5、反应时间150min。采用选择沉淀法分离CPP,在pH4.5添加1.1%CaCl2(w/v)和50%(v/v)乙醇,室温沉淀4h,得到CPP产品的N/P、得率分别为6.39%和13.94%。%In this study, alcalase was used for producing CPP by hydrolyzing casein. The optimum conditions: casein concentration 10%, enzyme usage 1500u/g substrate, temperature 45℃, pH10. 5 and time 150mins were determined. A selective precipitation procedure was also used to isolate CPP from the hydrolyzate of casein. The N/P ratio and the yield of CPP obtained by adding 1.1% CaCl2 (w / v ) and 50% (v / v ) alcohol to the hyrolyzate at pH4. 5 were 6. 39% and 13.94% respectively.

  14. Antioxidant activity of yogurt made from milk characterized by different casein haplotypes and fortified with chestnut and sulla honeys.

    Science.gov (United States)

    Perna, Annamaria; Intaglietta, Immacolata; Simonetti, Amalia; Gambacorta, Emilio

    2014-11-01

    The aim of this work was to evaluate the antioxidant activity of yogurt made from milk characterized by different casein (CN) haplotypes (αs1-, β-, κ-CN) and fortified with chestnut and sulla honeys. The CN haplotype was determined by isoelectric focusing, whereas antioxidant activity of yogurt was measured using 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid and ferric-reducing antioxidant power. The statistical analysis showed a significant effect of the studied factors. The results showed that chestnut honey presented the highest phenolic acid and flavonoid contents, which are closely associated with its high antioxidant activity. The antioxidant activity of fortified yogurt samples was affected both by different CN haplotypes and by type of honey added. Yogurts fortified with chestnut honey showed higher antioxidant activity than those fortified with sulla honey. The different behavior observed among the fortified yogurts led us to hypothesize that the effects of protein-polyphenol complex on antioxidant activity are interactive. The results suggest that milk proteins polymorphism and polyphenols play different roles in affecting the bioavailability and the antioxidant activity of yogurt.

  15. Screening for K-Casein (CSN3 Gene Variation in Carpathian Goat Breed by Isoelectric focusing (IEF and DNA Sequencing

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    Adrian Valentin Balteanu

    2015-05-01

    Full Text Available In goats, k-casein (CSN3 locus is highly polymorphic with up to 16 allele currently characterized. They produce 13 protein variants (CSN3 that were classified in two groups (AIEF and BIEF, according to their isoelectric point. Isoelectric focusing (IEF of milk samples allows the detection of these two CSN3 groups, but for correct identification of CSN3 alleles DNA based genotyping methods are needed. Therefore the objective of this study was to identify the types of alleles occurring at the CSN3 locus in Carpathian goat breed by using a combined IEF and DNA sequencing approach. IEF analysis of milk samples collected from two Carpathian goat populations reared in Romania revealed two distinct CSN3 patterns. Amplification and sequencing of CSN3 cDNA obtained from these goats revealed four polymorphic sites located in the exon 4 that are responsible for amino acids substitutions, as compared with the reference sequence of A allele. By comparative analysis of IEF and cDNA sequencing data obtained from the two populations, we shown that AIEF alleles are represented by B allele, while BIEF alleles are represented by D allele. However, the variation of CSN3 locus in Carpathian goat breed could be more complex, therefore further studies are needed to characterize it.

  16. Activated CaMKII Couples GluN2B and Casein Kinase 2 to Control Synaptic NMDA Receptors

    Directory of Open Access Journals (Sweden)

    Antonio Sanz-Clemente

    2013-03-01

    Full Text Available Synaptic activity triggers a profound reorganization of the molecular composition of excitatory synapses. For example, NMDA receptors are removed from synapses in an activity- and calcium-dependent manner, via casein kinase 2 (CK2 phosphorylation of the PDZ ligand of the GluN2B subunit (S1480. However, how synaptic activity drives this process remains unclear because CK2 is a constitutively active kinase, which is not directly regulated by calcium. We show here that activated CaMKII couples GluN2B and CK2 to form a trimolecular complex and increases CK2-mediated phosphorylation of GluN2B S1480. In addition, a GluN2B mutant, which contains an insert to mimic the GluN2A sequence and cannot bind to CaMKII, displays reduced S1480 phosphorylation and increased surface expression. We find that although disrupting GluN2B/CaMKII binding reduces synapse number, it increases synaptic-GluN2B content. Therefore, the GluN2B/CaMKII association controls synapse density and PSD composition in an activity-dependent manner, including recruitment of CK2 for the removal of GluN2B from synapses.

  17. Preliminary study of a novel in-office bleaching therapy modified with a casein phosphopeptide-amorphous calcium phosphate.

    Science.gov (United States)

    Borges, Boniek Castillo Dutra; Pinheiro, Mônica Heloisa Morais; Feitosa, Diala Aretha De Sousa; Correia, Tereza Cristina; Braz, Rodivan; Montes, Marcos Antônio Japiassú Resende; Pinheiro, Isauremi Vieira De Assunção

    2012-11-01

    Although in-office bleaching has been proven successful for bleaching teeth, controversy exists from morphological alterations in enamel morphology due to mineral loss and tooth sensitivity. This preliminary study aimed to evaluate the efficacy of a novel in-office tooth bleaching technique modified with a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (MI paste-MI) and its effect on the enamel morphology and tooth sensitivity. Three patients received a 35% hydrogen peroxide (Whiteness HP-HP) dental bleaching system. HP was prepared and applied on the teeth on one of the hemiarches, whilst teeth on the other hemiarch were bleached with a mixture of HP and MI. Tooth color, epoxy resin replicas, and sensitivity levels were evaluated in the upper incisors. The results were analyzed descriptively. Right and left incisors showed similar color change after bleaching. Incisors bleached with the mixture of HP and MI presented unaltered enamel surfaces and lower sensitivity levels. The currently tested tooth bleaching technique did not reduce the gel effectiveness while decreasing hypersensitivity levels and protecting the enamel against surface alterations caused by the high-concentration bleaching peroxide tested. The concomitant use of MI Paste and high-concentration hydrogen peroxide might be a successful method for decreasing tooth sensitivity and limiting changes in the enamel morphology during in-office bleaching.

  18. Use of /γ-irradiation to produce films from whey, casein and soya proteins: structure and functionals characteristics

    Science.gov (United States)

    Lacroix, M.; Le, T. C.; Ouattara, B.; Yu, H.; Letendre, M.; Sabato, S. F.; Mateescu, M. A.; Patterson, G.

    2002-03-01

    γ-irradiation and thermal treatments have been used to produce sterilized cross-linked films. Formulations containing variable concentrations of calcium caseinate and whey proteins (whey protein isolate (WPI) and commercial whey protein concentrate) or mixture of soya protein isolate (SPI) with WPI was investigated on the physico-chemical properties of these films. Results showed that the mechanical properties of cross-linked films improved significantly the puncture strength for all types of films. Size-exclusion chromatography showed for no cross-linked proteins, a molecular mass of around 40 kDa. The soluble fractions of the cross-linked proteins molecular distributions were between 600 and 3800 kDa. γ-irradiation seems to modify to a certain extent the conformation of proteins which will adopt structures more ordered and more stable, as suggested by X-ray diffraction analysis. Microstructure observations showed that the mechanical characteristics of these films are closely related to their microscopic structure. Water vapor permeability of films based on SPI was also significantly decreased when irradiated. Microbial resistance was also evaluated for cross-linked films. Results showed that the level of biodegradation of cross-linked films was 36% after 60 d of fermentation in the presence of Pseudomonas aeruginosa.

  19. Casein Kinase 1δ Is an APC/CCdh1 Substrate that Regulates Cerebellar Granule Cell Neurogenesis

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    Clara Penas

    2015-04-01

    Full Text Available Although casein kinase 1δ (CK1δ is at the center of multiple signaling pathways, its role in the expansion of CNS progenitor cells is unknown. Using mouse cerebellar granule cell progenitors (GCPs as a model for brain neurogenesis, we demonstrate that the loss of CK1δ or treatment of GCPs with a highly selective small molecule inhibits GCP expansion. In contrast, CK1δ overexpression increases GCP proliferation. Thus, CK1δ appears to regulate GCP neurogenesis. CK1δ is targeted for proteolysis via the anaphase-promoting complex/cyclosome (APC/CCdh1 ubiquitin ligase, and conditional deletion of the APC/CCdh1 activator Cdh1 in cerebellar GCPs results in higher levels of CK1δ. APC/CCdh1 also downregulates CK1δ during cell-cycle exit. Therefore, we conclude that APC/CCdh1 controls CK1δ levels to balance proliferation and cell-cycle exit in the developing CNS. Similar studies in medulloblastoma cells showed that CK1δ holds promise as a therapeutic target.

  20. Competitive displacement of sodium caseinate by low-molecular-weight emulsifiers and the effects on emulsion texture and rheology.

    Science.gov (United States)

    Munk, M B; Larsen, F H; van den Berg, F W J; Knudsen, J C; Andersen, M L

    2014-07-29

    Low-molecular-weight (LMW) emulsifiers are used to promote controlled destabilization in many dairy-type emulsions in order to obtain stable foams in whippable products. The relation between fat globule aggregation induced by three LMW emulsifiers, lactic acid ester of monoglyceride (LACTEM), saturated monoglyceride (GMS), and unsaturated monoglyceride (GMU) and their effect on interfacial protein displacement was investigated. It was found that protein displacement by LMW emulsifiers was not necessary for fat globule aggregation in emulsions, and conversely fat globule aggregation was not necessarily accompanied by protein displacement. The three LMW emulsifiers had very different effects on emulsions. LACTEM induced shear instability of emulsions, which was accompanied by protein displacement. High stability was characteristic for emulsions with GMS where protein was displaced from the interface. Emulsions containing GMU were semisolid, but only low concentrations of protein were detected in the separated serum phase. The effects of LACTEM, GMS, and GMU may be explained by three different mechanisms involving formation of interfacial α-gel, pickering stabilization and increased exposure of bound casein to the water phase. The latter may facilitate partial coalescence. Stabilizing hydrocolloids did not have any effect on the LMW emulsifiers' ability to induce protein displacement.

  1. Role of casein phosphopeptide amorphous calcium phosphate in remineralization of white spot lesions and inhibition of Streptococcus mutans?

    Science.gov (United States)

    Vashisht, Ruchi; Indira, Rajamani; Ramachandran, S; Kumar, Anil; Srinivasan, Manali Ramakrishnan

    2013-01-01

    Introduction: To promote the remineralization by ionic exchange mechanism instead of invasive techniques many remineralizing agents can be used. Objective: To evaluate the remineralization effects of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on white spot lesions (WSLs) and its inhibitory effect on Streptococcus mutans colonization. Materials and Methods: The study group consisted of 60 subjects exhibiting at least 1-WSL. Subjects were randomly divided into 2 groups: A test group using CPP-ACP cream (GC-Tooth Mousse, Leuven, Belgium) and a control group using only fluoride containing toothpaste for a period of 3-month. Baseline WSLs were scored using DIAGNOdent device (KaVo Germany) and the saliva samples were collected to measure S. mutans counts. After the 3-month period the WSLs were again recorded and the saliva collection was repeated. Result: DIAGNOdent measurements were increased by time (P = 0.002) in the control group and no statistically significant difference (P = 0.217) was found in the test group by the 3-month period. In both groups, the mutans counts were decreased in the 3-month experimental period. Conclusion: These clinical and laboratory results suggested that CPP-ACP containing cream had a slight remineralization effect on the WSL in the 3-month evaluation period however, longer observation is recommended to confirm whether the greater change in WSLs is maintained. PMID:23956538

  2. Addition of pectin and soy soluble polysaccharide affects the particle size distribution of casein suspensions prepared from acidified skim milk.

    Science.gov (United States)

    Liu, JinRu; Nakamura, Akihiro; Corredig, Milena

    2006-08-23

    Pectins are negatively charged polysaccharides employed as stabilizers in acidified milk dispersions, where caseins aggregate because of the low pH and serum separation needs to be prevented. The objective of this research was to study the effect of charge on the stabilizing functionality of the polysaccharide in acid milk drinks. Unstandardized pectins with various charges (as degree of esterification, DE) as well as soybean soluble polysaccharide (SSPS) were tested for their stabilizing behavior as a function of pH and concentration. Skim milk was acidified by glucono-delta-lactone and then homogenized in the presence of polysaccharide at different pH values (in the range from 4.2 to 3.0). Measurements of particle size distribution demonstrated that pectins with a DE of 71.4, 68.6, and 67.4 stabilized milk at pH > 4.0. Pectins with a lower DE (63.9%) needed a higher concentration (0.4%) at the same pH to show a monomodal distribution of particle sizes. Pectins with lower DE (milk, at pH milk dispersion was pH-dependent, and results were similar to those for samples containing pectin alone. This suggested that in the mixture, pectin dominated the behavior over SSPS, even when an excess of SSPS was added to the dispersions before homogenization.

  3. Recovery of Whey Proteins and Enzymatic Hydrolysis of Lactose Derived from Casein Whey Using a Tangential Flow Ultrafiltration Module

    Science.gov (United States)

    Das, Bipasha; Bhattacharjee, Sangita; Bhattacharjee, Chiranjib

    2013-09-01

    In this study, ultrafiltration (UF) of pretreated casein whey was carried out in a cross-flow module fitted with 5 kDa molecular weight cut-off polyethersulfone membrane to recover whey proteins in the retentate and lactose in the permeate. Effects of processing conditions, like transmembrane pressure and pH on permeate flux and rejection were investigated and reported. The polarised layer resistance was found to increase with time during UF even in this high shear device. The lactose concentration in the permeate was measured using dinitro salicylic acid method. Enzymatic kinetic study for lactose hydrolysis was carried out at three different temperatures ranging from 30 to 50 °C using β-galactosidase enzyme. The glucose formed during lactose hydrolysis was analyzed using glucose oxidase-peroxidase method. Kinetics of enzymatic hydrolysis of lactose solution was found to follow Michaelis-Menten model and the model parameters were estimated by Lineweaver-Burk plot. The hydrolysis rate was found to be maximum (with Vmax = 5.5091 mmol/L/min) at 30 °C.

  4. Contribution of casein kinase 2 and spleen tyrosine kinase to CFTR trafficking and protein kinase A-induced activity.

    Science.gov (United States)

    Luz, Simão; Kongsuphol, Patthara; Mendes, Ana Isabel; Romeiras, Francisco; Sousa, Marisa; Schreiber, Rainer; Matos, Paulo; Jordan, Peter; Mehta, Anil; Amaral, Margarida D; Kunzelmann, Karl; Farinha, Carlos M

    2011-11-01

    Previously, the pleiotropic "master kinase" casein kinase 2 (CK2) was shown to interact with CFTR, the protein responsible for cystic fibrosis (CF). Moreover, CK2 inhibition abolished CFTR conductance in cell-attached membrane patches, native epithelial ducts, and Xenopus oocytes. CFTR possesses two CK2 phosphorylation sites (S422 and T1471), with unclear impact on its processing and trafficking. Here, we investigated the effects of mutating these CK2 sites on CFTR abundance, maturation, and degradation coupled to effects on ion channel activity and surface expression. We report that CK2 inhibition significantly decreased processing of wild-type (wt) CFTR, with no effect on F508del CFTR. Eliminating phosphorylation at S422 and T1471 revealed antagonistic roles in CFTR trafficking: S422 activation versus T1471 inhibition, as evidenced by a severe trafficking defect for the T1471D mutant. Notably, mutation of Y512, a consensus sequence for the spleen tyrosine kinase (SYK) possibly acting in a CK2 context adjacent to the common CF-causing defect F508del, had a strong effect on both maturation and CFTR currents, allowing the identification of this kinase as a novel regulator of CFTR. These results reinforce the importance of CK2 and the S422 and T1471 residues for regulation of CFTR and uncover a novel regulation of CFTR by SYK, a recognized controller of inflammation.

  5. Use of {gamma}-irradiation to produce films from whey, casein and soya proteins: structure and functionals characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, M. E-mail: monique.lacroix@inrs-iaf.uquebec.ca; Le, T.C.; Ouattara, B.; Yu, H.; Letendre, M.; Sabato, S.F.; Mateescu, M.A.; Patterson, G

    2002-03-01

    {gamma}-irradiation and thermal treatments have been used to produce sterilized cross-linked films. Formulations containing variable concentrations of calcium caseinate and whey proteins (whey protein isolate (WPI) and commercial whey protein concentrate) or mixture of soya protein isolate (SPI) with WPI was investigated on the physico-chemical properties of these films. Results showed that the mechanical properties of cross-linked films improved significantly the puncture strength for all types of films. Size-exclusion chromatography showed for no cross-linked proteins, a molecular mass of around 40 kDa. The soluble fractions of the cross-linked proteins molecular distributions were between 600 and 3800 kDa. {gamma}-irradiation seems to modify to a certain extent the conformation of proteins which will adopt structures more ordered and more stable, as suggested by X-ray diffraction analysis. Microstructure observations showed that the mechanical characteristics of these films are closely related to their microscopic structure. Water vapor permeability of films based on SPI was also significantly decreased when irradiated. Microbial resistance was also evaluated for cross-linked films. Results showed that the level of biodegradation of cross-linked films was 36% after 60 d of fermentation in the presence of Pseudomonas aeruginosa.

  6. Effect of casein to whey protein ratios on the protein interactions and coagulation properties of low-fat yogurt.

    Science.gov (United States)

    Zhao, L L; Wang, X L; Tian, Q; Mao, X Y

    2016-10-01

    In this study, we investigated the effect of casein (CN) to whey protein (WP) ratios (4:1, 3:1, 2:1, and 1:1) on gelation properties and microstructure of low-fat yogurt made with reconstituted skim milk with or without addition of whey protein concentrate. The rheological properties (storage modulus, G'; yield stress; and yield strain) of the obtained low-fat yogurt were greatly enhanced, the fermentation period was shortened, and the microstructure became more compact with smaller pores as the CN:WP ratio decreased. When CN:WP was 2:1 or 1:1, the obtained yogurt coagulum showed higher G' and greater yield stress, with more compact crosslinking and smaller pores. In addition, the more of skim milk powder was replaced by whey protein concentrate, the more disulfide bonds were formed and the greater the occurrence of hydrophobic interactions during heat treatment, which can improve the rheological properties and microstructure of low-fat yogurt.

  7. Short- and Long-Term Soy Diet Versus Casein Protects Liver Steatosis Independent of the Arginine Content.

    Science.gov (United States)

    Hakkak, Reza; Zeng, Huawei; Dhakal, Ishwori B; Korourian, Soheila

    2015-11-01

    Nonalcoholic fatty liver disease, a major cause of abnormal liver function, is often associated with obesity. Arginine (ARG) plays a role in modulating body weight/fat, but limited data exist as to the role of ARG in soy protein's ability to protect from liver steatosis. We investigated the role of native ARG in the soy protein isolate (SPI) in reducing liver steatosis in male obese Zucker rats. Rats (N=48; 6 weeks old) were randomly assigned to one of three diets for 8 or 16 weeks: the casein (CAS) diet as control (0.6% ARG), CAS diet supplemented to contain 1.3% ARG, or an SPI diet containing isoflavones (1.3% ARG). SPI and ARG rats gained significantly more weight (Pdiet had no effect on steatosis or ALT and AST levels. We found that the SPI diet reduced (Pdiets after 8 and 16 weeks. The SPI diet significantly reduced (Pdiet at 8 weeks, but there was no significant difference at 16 weeks. Based on the findings of our study, the protective effect of SPI in reducing liver steatosis is not modulated by its native arginine content.

  8. Role of casein phosphopeptide amorphous calcium phosphate in remineralization of white spot lesions and inhibition of Streptococcus mutans?

    Directory of Open Access Journals (Sweden)

    Ruchi Vashisht

    2013-01-01

    Full Text Available Introduction: To promote the remineralization by ionic exchange mechanism instead of invasive techniques many remineralizing agents can be used. Objective: To evaluate the remineralization effects of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP on white spot lesions (WSLs and its inhibitory effect on Streptococcus mutans colonization. Materials and Methods: The study group consisted of 60 subjects exhibiting at least 1-WSL. Subjects were randomly divided into 2 groups: A test group using CPP-ACP cream (GC-Tooth Mousse, Leuven, Belgium and a control group using only fluoride containing toothpaste for a period of 3-month. Baseline WSLs were scored using DIAGNOdent device (KaVo Germany and the saliva samples were collected to measure S. mutans counts. After the 3-month period the WSLs were again recorded and the saliva collection was repeated. Result: DIAGNOdent measurements were increased by time (P = 0.002 in the control group and no statistically significant difference (P = 0.217 was found in the test group by the 3-month period. In both groups, the mutans counts were decreased in the 3-month experimental period. Conclusion: These clinical and laboratory results suggested that CPP-ACP containing cream had a slight remineralization effect on the WSL in the 3-month evaluation period however, longer observation is recommended to confirm whether the greater change in WSLs is maintained.

  9. Iron casein succinylate-chitosan coacervate for the liquid oral delivery of iron with bioavailability and stability enhancement.

    Science.gov (United States)

    Min, Kyoung Ah; Cho, Jung-Hye; Song, Yun-Kyoung; Kim, Chong-Kook

    2016-01-01

    Iron casein succinylate (ICS) liquid oral preparation as iron supplement has uncomfortable taste after a long period of storage because of its stability, and poor bioavailability of iron compared to any other iron preparations. To improve the chemical stability of ICS and enhance the bioavailability of iron, chitosan-ICS nanoparticles (NPs) were prepared by complex coacervation method and stabilized with polyethylene glycol (PEG) 400. NPs were spherical (mean diameter of 830-1070 nm) with positive charge (+30-60 mV) depending on the composition of NPs. Addition of PEG400 (2 w/v %) increased the zeta potential (26-50 %) and physical stability of chitosan-ICS NPs suspension. Also, NPs decreased iron release compared to ICS after 7-weeks of storage at 4 °C. NPs markedly increased the permeability of iron in Caco-2 cell up to 32-38-fold compared to ICS, while physical mixture of chitosan and ICS increased the iron permeability only 2.5-fold. In summary, NPs improved the physicochemical stability and enhanced the transport of iron compared to other iron preparations in Caco-2 cell model. Thus, chitosan-ICS coacervate might be a promising candidate as a liquid oral iron delivery system for iron deficiency patients with stability and bioavailability enhancement.

  10. Effect of Prolactin Receptor (PRLR) and Beta-Casein (CSN2) Gene Polymorphism on the Chemical Composition of Milk Sows.

    Science.gov (United States)

    Skrzypczak, Ewa; Babicz, Marek; Pastwa, Marcin

    2015-01-01

    The objective of the studies was to evaluate the impact of the prolactin receptor and β-casein genes on the basic chemical composition and pH of the colostrum and milk of sows. Experiments were carried out on 103 Złotnicka White breed sows. These animals are under the Domestic Program of Protection of Genetic Resources. Analysis of the influence of polymorphism in the PRLR and CSN2 loci revealed that sows of the TT homozygote were characterised by the highest dry matter content. Analysis of polymorphism in the PRLR locus for protein showed that the highest values were in milk of sows of the TT genotype, and GG homozygotes in the case of the CSN2 locus. Inference of the impact of polymorphism in the PRLR and CSN2 loci on the fat and lactose content of sow milk demonstrated considerable variability. These differences were statistically significant at the level of α = 0.01 and α = 0.05. Periodical changes in individual pH values were apparent for particular genotypes in both loci (PRLR and CSN2). The perceptible changes that occurred between individual genotypes were statistically significant at the levels of α = 0.01 and α = 0.05. The investigations confirmed that the nutritive values of sow colostrum and milk were determined by genetic factors. This issue warrants comprehensive analysis, especially in terms of evaluation of the breeding value of maternal breeds.

  11. Effect of prolactin, beta-lactoglobulin, and kappa-casein genotype on milk yield in East Friesian sheep.

    Science.gov (United States)

    Staiger, E A; Thonney, M L; Buchanan, J W; Rogers, E R; Oltenacu, P A; Mateescu, R G

    2010-04-01

    The effect of prolactin (PRL), beta-lactoglobulin (beta-LG), and kappa-casein (CSN3) on milk yield was estimated in an East Friesian dairy sheep population from Old Chatham Sheepherding Company, New York. Genotypes were determined by PCR amplification followed by digestion with HaeIII and RsaI for PRL and beta-LG, respectively, and by PCR amplification for CSN3. Monthly milking records and pedigree information were used to evaluate the effect of each polymorphism on milk yield. Results indicated that PRL genotype had a significant effect on milk yield. Ewes carrying one A allele produced 110.6g more milk per day than ewes with no A alleles. There was no statistical difference between ewes with only one A allele and ewes with 2 A alleles. No association among polymorphisms at the beta-LG and CSN3 loci and milk yield was found. The results presented in this study indicate that the PRL gene is a potential marker that could be used in selection programs for improving milk yield in dairy sheep.

  12. Caseinomacropeptide self-association is dependent on whether the peptide is free or restricted in kappa-casein

    DEFF Research Database (Denmark)

    Mikkelsen, T.L.; Frokiaer, H.; Topp, C.

    2005-01-01

    dodecyl sulfate-PAGE, N-terminal sequencing, and mass spectrometry. The hydrophobicity of CMP was studied by means of 1-anilino-naphthalene-8-sulfonic acid binding experiments. Four CMP products prepared by different methods were studied: CMP produced by enzymatic (chymosin or pepsin) hydrolysis of kappa......-casein (CN), and 2 commercial CMP products. Both commercial products and CMP-resulting from chymosin-hydrolysis of kappa-CN (at pH 6.6) had elution volumes with a MW corresponding to 35 kDA at pH 8.0 and 3.4. Caseinomacropeptide prepared from pepsin-hydrolysis of kappa-CN (at pH 2.5) eluted as multiple peaks...... with apparent MW of 35, 18, and 9 kDa, again independently of pH. Hydrolysis of kappa-CN with chymosin or pepsin at different pH values (pH 2.5, 3.4, and 6.6) produced differently sized aggregates of CMP, largely depending on the pH of the hydrolysis. These results indicate that, whereas CMP molecules...

  13. Thermal properties of milk fat, xanthine oxidase, caseins and whey proteins in pulsed electric field-treated bovine whole milk.

    Science.gov (United States)

    Sharma, Pankaj; Oey, Indrawati; Everett, David W

    2016-09-15

    Thermodynamics of milk components (milk fat, xanthine oxidase, caseins and whey proteins) in pulsed electric field (PEF)-treated milk were compared with thermally treated milk (63 °C for 30 min and 73 °C for 15s). PEF treatments were applied at 20 or 26 kV cm(-1) for 34 μs with or without pre-heating of milk (55 °C for 24s), using bipolar square wave pulses in a continuous mode of operation. PEF treatments did not affect the final temperatures of fat melting (Tmelting) or xanthine oxidase denaturation (Tdenaturation), whereas thermal treatments increased both the Tmelting of milk fat and the Tdenaturation for xanthine oxidase by 2-3 °C. Xanthine oxidase denaturation was ∼13% less after PEF treatments compared with the thermal treatments. The enthalpy change (ΔH of denaturation) of whey proteins decreased in the treated-milk, and denaturation increased with the treatment intensity. New endothermic peaks in the calorimetric thermograms of treated milk revealed the formation of complexes due to interactions between MFGM (milk fat globule membrane) proteins and skim milk proteins. Evidence for the adsorption of complexes onto the MFGM surface was obtained from the increase in surface hydrophobicity of proteins, revealing the presence of unfolded hydrophobic regions.

  14. FAM83H and casein kinase I regulate the organization of the keratin cytoskeleton and formation of desmosomes

    Science.gov (United States)

    Kuga, Takahisa; Sasaki, Mitsuho; Mikami, Toshinari; Miake, Yasuo; Adachi, Jun; Shimizu, Maiko; Saito, Youhei; Koura, Minako; Takeda, Yasunori; Matsuda, Junichiro; Tomonaga, Takeshi; Nakayama, Yuji

    2016-01-01

    FAM83H is essential for the formation of dental enamel because a mutation in the FAM83H gene causes amelogenesis imperfecta (AI). We previously reported that the overexpression of FAM83H often occurs and disorganizes the keratin cytoskeleton in colorectal cancer cells. We herein show that FAM83H regulates the organization of the keratin cytoskeleton and maintains the formation of desmosomes in ameloblastoma cells. FAM83H is expressed and localized on keratin filaments in human ameloblastoma cell lines and in mouse ameloblasts and epidermal germinative cells in vivo. FAM83H shows preferential localization to keratin filaments around the nucleus that often extend to cell-cell junctions. Alterations in the function of FAM83H by its overexpression, knockdown, or an AI-causing truncated mutant prevent the proper organization of the keratin cytoskeleton in ameloblastoma cells. Furthermore, the AI-causing mutant prevents desmosomal proteins from being localized to cell-cell junctions. The effects of the AI-causing mutant depend on its binding to and possible inhibition of casein kinase I (CK-1). The suppression of CK-1 by its inhibitor, D4476, disorganizes the keratin cytoskeleton. Our results suggest that AI caused by the FAM83H mutation is mediated by the disorganization of the keratin cytoskeleton and subsequent disruption of desmosomes in ameloblasts. PMID:27222304

  15. Comparative characteristics of DNA polymorphisms of κ-casein gene (CSN3) in the horse and donkey.

    Science.gov (United States)

    Selvaggi, M; D'Alessandro, A G; Dario, C

    2015-11-19

    The aims of this study were to assess the genetic variability in the exon 1 of the κ-casein gene in four Italian horse populations (Italian Saddle horse, Italian Trotter, Italian Heavy Draught horse, and Murgese horse) and in a sample of Martina Franca donkey by estimating genotype, allele and haplotype frequencies, as well as several population genetic indices. Genotyping of the selected polymorphisms was performed using the PCR-RFLP technique with two restriction enzymes: PstI and BseYI aimed to discover the presence of c.-66A>G and c.-36C>A polymorphism, respectively. Both these loci were found to be polymorphic in horses with some differences depending on the breed. No genetic variability was observed in Martina Franca donkey breed. In the equine species no selective pressure for milk purpose was performed, therefore the polymorphisms at milk protein loci were mainly considered as result of natural selection or as indirect consequence of selection oriented to increase body size or to improve conformation. From this point of view these two single nucleotide polymorphisms and particularly the c.-36C>A one could be useful instruments for population studies.

  16. Ricinine: a pyridone alkaloid from Ricinus communis that activates the Wnt signaling pathway through casein kinase 1α.

    Science.gov (United States)

    Ohishi, Kensuke; Toume, Kazufumi; Arai, Midori A; Sadhu, Samir K; Ahmed, Firoj; Mizoguchi, Takamasa; Itoh, Motoyuki; Ishibashi, Masami

    2014-09-01

    Wnt signaling plays important roles in proliferation, differentiation, development of cells, and various diseases. Activity-guided fractionation of the MeOH extract of the Ricinus communis stem led to the isolation of four compounds (1-4). The TCF/β-catenin transcription activities of 1 and 3 were 2.2 and 2.5 fold higher at 20 and 30μM, respectively. Cells treated with ricinine (1) had higher β-catenin and lower of p-β-catenin (ser 33, 37, 45, Thr 41) protein levels, whereas glycogen synthase kinase 3β (GSK3β) and casein kinase 1α (CK1α) protein levels remained unchanged. Cells treated with pyrvinium, an activator of CK1α, had lower β-catenin levels. However, the combined treatment of pyrvinium and 1 led to higher β-catenin levels than those in cells treated with pyrvinium alone, which suggested that 1 inhibited CK1α activity. Furthermore, 1 increased β-catenin protein levels in zebrafish embryos. These results indicated that 1 activated the Wnt signaling pathway by inhibiting CK1α.

  17. Interactions between Casein kinase Iepsilon (CKIepsilon and two substrates from disparate signaling pathways reveal mechanisms for substrate-kinase specificity.

    Directory of Open Access Journals (Sweden)

    Caroline Lund Dahlberg

    Full Text Available BACKGROUND: Members of the Casein Kinase I (CKI family of serine/threonine kinases regulate diverse biological pathways. The seven mammalian CKI isoforms contain a highly conserved kinase domain and divergent amino- and carboxy-termini. Although they share a preferred target recognition sequence and have overlapping expression patterns, individual isoforms often have specific substrates. In an effort to determine how substrates recognize differences between CKI isoforms, we have examined the interaction between CKIepsilon and two substrates from different signaling pathways. METHODOLOGY/PRINCIPAL FINDINGS: CKIepsilon, but not CKIalpha, binds to and phosphorylates two proteins: Period, a transcriptional regulator of the circadian rhythms pathway, and Disheveled, an activator of the planar cell polarity pathway. We use GST-pull-down assays data to show that two key residues in CKIalpha's kinase domain prevent Disheveled and Period from binding. We also show that the unique C-terminus of CKIepsilon does not determine Dishevelled's and Period's preference for CKIepsilon nor is it essential for binding, but instead plays an auxillary role in stabilizing the interactions of CKIepsilon with its substrates. We demonstrate that autophosphorylation of CKIepsilon's C-terminal tail prevents substrate binding, and use mass spectrometry and chemical crosslinking to reveal how a phosphorylation-dependent interaction between the C-terminal tail and the kinase domain prevents substrate phosphorylation and binding. CONCLUSIONS/SIGNIFICANCE: The biochemical interactions between CKIepsilon and Disheveled, Period, and its own C-terminus lead to models that explain CKIepsilon's specificity and regulation.

  18. Structure-Activity Relationship of Synthetic Variants of the Milk-Derived Antimicrobial Peptide αs2-Casein f(183–207)

    Science.gov (United States)

    Begley, Máire; Clifford, Tanya; Deasy, Thérèse; Considine, Kiera; Hill, Colin

    2013-01-01

    Template-based studies on antimicrobial peptide (AMP) derivatives obtained through manipulation of the amino acid sequence are helpful to identify properties or residues that are important for biological activity. The present study sheds light on the importance of specific amino acids of the milk-derived αs2-casein f(183–207) peptide to its antibacterial activity against the food-borne pathogens Listeria monocytogenes and Cronobacter sakazakii. Trimming of the peptide revealed that residues at the C-terminal end of the peptide are important for activity. Removal of the last 5 amino acids at the C-terminal end and replacement of the Arg at position 23 of the peptide sequence by an Ala residue significantly decreased activity. These findings suggest that Arg23 is very important for optimal activity of the peptide. Substitution of the also positively charged Lys residues at positions 15 and 17 of the αs2-casein f(183–207) peptide also caused a significant reduction of the effectiveness against C. sakazakii, which points toward the importance of the positive charge of the peptide for its biological activity. Indeed, simultaneous replacement of various positively charged amino acids was linked to a loss of bactericidal activity. On the other hand, replacement of Pro residues at positions 14 and 20 resulted in a significantly increased antibacterial potency, and hydrophobic end tagging of αs2-casein f(193–203) and αs2-casein f(197–207) peptides with multiple Trp or Phe residues significantly increased their potency against L. monocytogenes. Finally, the effect of pH (4.5 to 7.4), temperature (4°C to 37°C), and addition of sodium and calcium salts (1% to 3%) on the activity of the 15-amino-acid αs2-casein f(193–207) peptide was also determined, and its biological activity was shown to be completely abolished in high-saline environments. PMID:23793637

  19. Simultaneous quantification of α-lactalbumin and β-casein in human milk using ultra-performance liquid chromatography with tandem mass spectrometry based on their signature peptides and winged isotope internal standards.

    Science.gov (United States)

    Chen, Qi; Zhang, Jingshun; Ke, Xing; Lai, Shiyun; Li, Duo; Yang, Jinchuan; Mo, Weimin; Ren, Yiping

    2016-09-01

    In recent years, there is an increasing need to measure the concentration of individual proteins in human milk, instead of total human milk proteins. Due to lack of human milk protein standards, there are only few quantification methods established. The objective of the present work was to develop a simple and rapid quantification method for simultaneous determination of α-lactalbumin and β-casein in human milk using signature peptides according to a modified quantitative proteomics strategy. The internal standards containing the signature peptide sequences were synthesized with isotope-labeled amino acids. The purity of synthesized peptides as standards was determined by amino acid analysis method and area normalization method. The contents of α-lactalbumin and β-casein in human milk were measured according to the equimolar relationship between the two proteins and their corresponding signature peptides. The method validation results showed a satisfied linearity (R(2)>0.99) and recoveries (97.2-102.5% for α-lactalbumin and 99.5-100.3% for β-casein). The limit of quantification for α-lactalbumin and β-casein was 8.0mg/100g and 1.2mg/100g, respectively. CVs for α-lactalbumin and β-casein in human milk were 5.2% and 3.0%. The contents of α-lactalbumin and β-casein in 147 human milk samples were successfully determined by the established method and their contents were 205.5-578.2mg/100g and 116.4-467.4mg/100g at different lactation stages. The developed method allows simultaneously determination of α-lactalbumin and β-casein in human milk. The quantitative strategy based on signature peptide should be applicable to other endogenous proteins in breast milk and other body fluids.

  20. Effect of heat treatment on the mechanical properties of Casein-g-Poly(acrylonitrile) fibers%热处理对酪蛋白改性丙烯腈纤维力学性能的影响

    Institute of Scientific and Technical Information of China (English)

    高晶; 俞建勇; 任海龙

    2009-01-01

    对4种不同投料比酪蛋白接枝丙烯腈纤维的不同热处理条件下机械性能进行了研究.结果显示,酪蛋白接枝改性丙烯进纤维的性能随温度变化比较敏感,且酪蛋白投料比含量越大,高温处理对纤维交互作用的影响越显著,纤维的断裂强度和断裂伸长均有所提高.但高温处理后酪蛋白纤维由于热氧化分解而使其颜色逐渐发黄.纤维的横截面SEM图像显示了不同投料比改性纤维的内部结构.%Four kinds of casein-g-poly (acrylonitrile) fibers with different casein content were prepared, and mechanical properties were investigated after different heat treatment. The results show that the grafted casein fibers were sensitive to temperature. With the increase of casein content, the effect of cross-linking performance in fiber increased after high temperature treatment. The strength and elongation at break both trended to increase. But the colors of fibers gradually changed into yellow under the higher temperature, due to the thermal oxidative decomposition of casein. SEM observations on the cross-section surface of modified fibers show the different structures in grafted casein fibers with different casein contents.

  1. 琥珀酰化修饰改善牦牛乳酪蛋白胶束结构及疏水性%Succinylation improves structure and hydrophobicity of yak casein micelles

    Institute of Scientific and Technical Information of China (English)

    杨敏; 梁琪; 毕阳; 文鹏程; 张卫兵; 杨继涛

    2013-01-01

      琥珀酰化是改善食品蛋白质功能性质的常用手段,牦牛乳是青藏高原特色乳资源。为了揭示琥珀酰化对牦牛乳酪蛋白胶束结构的修饰作用,以牦牛乳酪蛋白为原料,研究了琥珀酰化修饰对其结构及疏水性的影响。分别通过傅里叶变换红外光谱分析了修饰前后酪蛋白胶束二级结构变化,采用动态光散射技术分析了修饰前后酪蛋白胶束粒径变化,采用扫描电镜技术观察了酰化反应对酪蛋白的表面形貌的影响。结果显示,牦牛乳酪蛋白胶束二级结构为33.1%β-转角、23.2%无规卷曲,32.0%β-折叠和11.7%大环结构,α-螺旋结构未检出。琥珀酰化修饰后,α-螺旋结构形成,含量为12.4%,其他二级结构含量变化不大。琥珀酰化修饰使酪蛋白胶束粒径减小,由不规则的球形转变为规则的球形,疏水性显著降低。研究结果可为牦牛乳酪蛋白的改性提供参考依据。%Yak caseins are special materials whose structures are different from cow caseins. Chemical modification is commonly applied to improve the functional properties of food proteins, such as acylation, succinylation, esterification, oxidation, reduction, glycosylation, phosphorylation, and alkylation. Succinylation is a useful method for significantly improving the functional properties of protein;iexhaustive succinylation induces large changes in physio-chemical properties of caseins, particularly in their electrostatic nature. However, very little literature is available about the structures, physio-chemical, and functional properties of yak caseins to direct industry processing of yak caseins. The present work tested the influence of succinylated modification on the structure and hydrophobicity of yak casein micelles. The spatial structure of modified and unmodified yak casein micelles were studied by Fourier transformation infrared spectroscopy. The diameter of modified and unmodified casein

  2. Use of micellar casein concentrate for Greek-style yogurt manufacturing: effects on processing and product properties.

    Science.gov (United States)

    Bong, D D; Moraru, C I

    2014-03-01

    The objective of this work was to develop and optimize an alternative make process for Greek-style yogurt (GSY), in which the desired level of protein was reached by fortification with micellar casein concentrate (MCC) obtained from milk by microfiltration. Two MCC preparations with 58 and 88% total protein (MCC-58 and MCC-88) were used to fortify yogurt milk to 9.80% (wt/wt) protein. Strained GSY of similar protein content was used as the control. Yogurt milk bases were inoculated with 0.02% (wt/wt) or 0.04% (wt/wt) direct vat set starter culture and fermented until pH 4.5. The acidification rate was faster for the MCC-fortified GSY than for the control, regardless of the inoculation level, which was attributed to the higher nonprotein nitrogen content in the MCC-fortified milk. Steady shear rate rheological analysis indicated a shear-thinning behavior for all GSY samples, which fitted well with the power law model. Dynamic rheological analysis at 5°C showed a weak frequency dependency of the elastic modulus (G') and viscous modulus (G") for all GSY samples, with G' > G", indicating a weak gel structure. Differences in the magnitude of viscoelastic parameters between the 2 types of GSY were found, with G' of MCC-fortified GSY yogurt. Differences were also noticed in water-holding capacity, which was lower for the MCC-fortified GSY compared with the control, attributed to lower serum protein content in the former. Despite some differences in the physicochemical characteristics of the final product compared with GSY manufactured by straining, the alternative process developed here is a feasible alternative to the traditional GSY make process, with environmental and possibly financial benefits to the dairy industry.

  3. Casein Phosphopeptide-Amorphous Calcium Phosphate Reduces Streptococcus mutans Biofilm Development on Glass Ionomer Cement and Disrupts Established Biofilms

    Science.gov (United States)

    Liu, Sze-Wei; Myroforidis, Helen; Zalizniak, Ilya; Palamara, Joseph E. A.; Huq, N. Laila; Reynolds, Eric C.

    2016-01-01

    Glass ionomer cements (GIC) are dental restorative materials that are suitable for modification to help prevent dental plaque (biofilm) formation. The aim of this study was to determine the effects of incorporating casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) into a GIC on the colonisation and establishment of Streptococcus mutans biofilms and the effects of aqueous CPP-ACP on established S mutans biofilms. S. mutans biofilms were either established in flow cells before a single ten min exposure to 1% w/v CPP-ACP treatment or cultured in static wells or flow cells with either GIC or GIC containing 3% w/w CPP-ACP as the substratum. The biofilms were then visualised using confocal laser scanning microscopy after BacLight LIVE/DEAD staining. A significant decrease in biovolume and average thickness of S. mutans biofilms was observed in both static and flow cell assays when 3% CPP-ACP was incorporated into the GIC substratum. A single ten min treatment with aqueous 1% CPP-ACP resulted in a 58% decrease in biofilm biomass and thickness of established S. mutans biofilms grown in a flow cell. The treatment also significantly altered the structure of these biofilms compared with controls. The incorporation of 3% CPP-ACP into GIC significantly reduced S. mutans biofilm development indicating another potential anticariogenic mechanism of this material. Additionally aqueous CPP-ACP disrupted established S. mutans biofilms. The use of CPP-ACP containing GIC combined with regular CPP-ACP treatment may lower S. mutans challenge. PMID:27589264

  4. Cyclooxygenase 2-dependent and independent activation of Akt through casein kinase 2α contributes to human bladder cancer cell survival

    Directory of Open Access Journals (Sweden)

    Fujimoto Kiyohide

    2011-05-01

    Full Text Available Abstract Background Survival rate for patients presenting muscle invasive bladder cancer is very low, and useful therapeutic target has not been identified yet. In the present study, new COX2 downstream signals involved in urothelial carcinoma cell survival were investigated in vitro and in vivo. Methods COX2 gene was silenced by siRNA transfection. Orthotopic implantation animal model and transurethral instillation of siRNA with atelocollagen was constructed to examine the effects of COX2 knockdown in vivo. Cell cycle was examined by flowcytoketry. Surgical specimens derived from patients with urinary bladder cancer (all were initially diagnosed cases were used for immunohistochemical analysis of the indicated protein expression in urothelial carcinoma cells. Results Treatment with the COX2 inhibitor or knockdown of COX2 reduced expression of casein kinase (CK 2 α, a phophorylated Akt and urokinase type plasminogen activator (uPA, resulting in p27 induction, cell cycle arrest at G1 phase and cell growth suppression in human urothelial carcinoma cell lines expressing COX2. Silencing of CK2α exhibited the similar effects. Even in UMUC3 cells lacking the COX2 gene, COX2 inhibition also inhibited cell growth through down-regulation of the CK2α-Akt/uPA axis. The mouse orthotropic bladder cancer model demonstrated that the COX2 inhibitor, meloxicam significantly reduced CK2α, phosphorylated Akt and uPA expression, whereas induced p27 by which growth and invasiveness of bladder cancer cells were strongly inhibited. Immunohistochemically, high expression of COX2, CK2α and phosphorylated form of Akt was found in high-grade, invasive carcinomas as well as carcinoma in situ, but not in low-grade and noninvasive phenotypes. Conclusions COX2-dependent and independent activation of CK2α-Akt/uPA signal is mainly involved in urothelial carcinoma cell survival, moreover, not only COX2 but also CK2α could be direct targets of COX2 inhibitors.

  5. Effect of casein phosphopeptide-amorphous calcium phosphate on the flexural strength of enamel-dentin complex following extracoronal bleaching

    Directory of Open Access Journals (Sweden)

    Diatri Nari Ratih

    2015-03-01

    Full Text Available Background: Bleaching can affect the mechanical properties of enamel-dentin complex, such as flexural strength. Casein phosphopeptide-amorphus calcium phosphate (CPP-ACP is often used following bleaching treatment to reduce hypersensitivity and to increase demineralization of tooth. Purpose: The purpose of the study was to investigate the effect of CPP-ACP on the flexural strength of enamel-dentin complex following extracoronal bleaching. Methods: Forty-eight enamel-dentin plates (size 8 x 2 x 3 mm were randomly assigned into 6 groups, each consisted of 8 samples. Group 1, no bleaching and immersed in artificial saliva. Group 2, no bleaching, CPP-ACP application only. Group 3, bleaching using 15% carbamide peroxide. Group 4, similar to group 3, except application of CPP-ACP for the times between bleaching. Group 5, bleaching with 40% hydrogen peroxide. Group 6, similar to group 5, except application of CPP-ACP for the times between bleaching. Flexural strength of each enamel-dentin plate was tested by threepoint bending test using universal testing machine. Results: The results showed that 15% carbamide peroxide and 40% hydrogen peroxide significantly reduced flexural strength of enamel-dentin (216.25±26.44 MPa and 206.67±32.07 MPa respectively. Conversely, application of CPP-ACP following both bleachings increased flexural strength (266.75± 28.27MPa and 254.58±36.59 MPa respectively. A two-way Anova revealed that extracoronal bleaching agents significantly reduced flexural strength (p<0.05. Conclusion: Extracoronal bleaching agents reduce flexural strength, whereas application of CPP-ACP following bleaching either with 15% carbamide peroxide or 40% hydrogen peroxide can increase the flexural strength of enamel-dentin complex.

  6. Clinical evaluation of remineralization potential of casein phosphopeptide amorphous calcium phosphate nanocomplexes for enamel decalcification in orthodontics

    Institute of Scientific and Technical Information of China (English)

    WANG Jun-xiang; YAN Yan; WANG Xiu-jing

    2012-01-01

    Background Enamel decalcification in orthodontics is a concern for dentists and methods to remineralize these lesions are the focus of intense research.The aim of this study was to evaluate the remineralizing effect of casein phosphopeptide amorphous calcium phosphate(CPP-ACP)nanocomplexes on enamel decalcification in orthodontics.Methods Twenty orthodontic patients with decalcified enamel lesions during fixed orthodontic therapy were recruited to this study as test group and twenty orthodontic patients with the similar condition as control group.GC Tooth Mousse,the main component of which is CPP-ACP,was used by each patient of test group every night after tooth-brushing for six months.For control group,each patient was asked to brush teeth with toothpaste containing 1100 parts per million(ppm)of fluoride twice a day.Standardized intraoral images were taken for all patients and the extent of enamel decalcification was evaluated before and after treatment over this study period.Measurements were statistically compared by t test.Results After using CPP-ACP for six months,the enamel decalcification index(EDI)of all patients had decreased;the mean EDI before using CPP-ACP was 0.191±0.025 and that after using CPP-ACP was 0.183±0.023,the difference was significant(t=5.169,P<0.01).For control group,the mean EDI before treatment was 0.188±0.037 and that after treatment was 0.187±0.046,the difference was not significant(t=1.711,P>0.05).Conclusion CPP-ACP can effectively improve the demineralized enamel lesions during orthodontic treatment,so it has some remineralization potential for enamel decalcification in orthodontics.

  7. Bioavailability of free lysine and protein-bound lysine from casein and fishmeal in juvenile turbot (Psetta maxima).

    Science.gov (United States)

    Kroeckel, Saskia; Dietz, Carsten; Schulz, Carsten; Susenbeth, Andreas

    2015-03-14

    In the present study, a linear regression analysis between lysine intake and lysine retention was conducted to investigate the efficiency of lysine utilisation (k(Lys)) at marginal lysine intake of either protein-bound or free lysine sources in juvenile turbot (Psetta maxima). For this purpose, nine isonitrogenous and isoenergetic diets were formulated to contain 2·25-4·12 g lysine/100 g crude protein (CP) to ensure that lysine was the first-limiting amino acid in all diets. The basal diet contained 2·25 g lysine/100 g CP. Graded levels of casein (Cas), fishmeal (FM) and L-lysine HCl (Lys) were added to the experimental diets to achieve stepwise lysine increments. A total of 240 fish (initial weight 50·1 g) were hand-fed all the experimental diets once daily until apparent satiation over a period of 56 d. Feed intake was significantly affected by dietary lysine concentration rather than by dietary lysine source. Specific growth rate increased significantly at higher lysine concentrations (PCas, Lys or FM were 0·833, 0·857 and 0·684, respectively. The bioavailability of lysine from the respective lysine sources was determined by a slope-ratio approach. The bioavailability of lysine (relative to the reference lysine source Cas) from FM and Lys was 82·1 and 103 %, respectively. Nutrient requirement for maintenance was in the range of 16·7-23·4 mg/kg(0·8) per d, and did not differ between the treatments. There were no significant differences in lysine utilisation efficiency or bioavailability of protein-bound or crystalline lysine from the respective sources observed when lysine was confirmed to be the first-limiting nutrient.

  8. Identification of a secreted casein kinase 1 in Leishmania donovani: effect of protein over expression on parasite growth and virulence.

    Directory of Open Access Journals (Sweden)

    Mary Dan-Goor

    Full Text Available Casein kinase 1 (CK1 plays an important role in eukaryotic signaling pathways, and their substrates include key regulatory proteins involved in cell differentiation, proliferation and chromosome segregation. The Leishmania genome encodes six potential CK1 isoforms, of which five have orthologs in other trypanosomatidae. Leishmania donovani CK1 isoform 4 (Ldck1.4, orthologous to LmjF27.1780 is unique to Leishmania and contains a putative secretion signal peptide. The full-length gene and three shorter constructs were cloned and expressed in E. coli as His-tag proteins. Only the full-length 62.3 kDa protein showed protein kinase activity indicating that the N-terminal and C-terminal domains are essential for protein activity. LdCK1.4-FLAG was stably over expressed in L. donovani, and shown by immunofluorescence to be localized primarily in the cytosol. Western blotting using anti-FLAG and anti-CK1.4 antibodies showed that this CK1 isoform is expressed and secreted by promastigotes. Over expression of LdCK1.4 had a significant effect on promastigote growth in culture with these parasites growing to higher cell densities than the control parasites (wild-type or Ld:luciferase, P<0.001. Analysis by flow cytometry showed a higher percentage, ∼4-5-fold, of virulent metacyclic promastigotes on day 3 among the LdCK1.4 parasites. Finally, parasites over expressing LdCK1.4 gave significantly higher infections of mouse peritoneal macrophages compared to wild-type parasites, 28.6% versus 6.3%, respectively (p = 0.0005. These results suggest that LdCK1.4 plays an important role in parasite survival and virulence. Further studies are needed to validate CK1.4 as a therapeutic target in Leishmania.

  9. Casein kinase Ⅱ interacts with prion protein in vitro and forms complex with na-tive prion protein in vivo

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The most essential and crucial step during the pathogenesis of transmissible spongiform encephalopathy is the conformational change of cellular prion protein to pathologic isoform. Casein kinase Ⅱ (CK2) is a ubiquitously expressed and evolutiouarily conserved pleiotropic protein kinase that is essential for viability. To explore the possible molecular interaction between CK2 and prion protein (PrP), the full-length sequences of human CK2α and CK2β complementary DNA were amplified with reverse transcription-polymerase chain reaction using the total messenger RNA from cell line SH-SY5Y as the template; then, the fusion proteins histidine-CK2α and glutathione S-transferase-histidine-CK2β were expressed in Escherichia coll. The interaction between CK2 and PrP was evaluated with co-immunoprecipi-tation and pull-down assays. The results demonstrated that recombinant PrP bound specifically with CK2α, but not with CK2β. The native CK2 and PrP in hamster brains interacted with each other, forming protein complexes. Three different glycosylated forms of PrP (diglycosylated, monoglycosylated and unglycosylated PrP) from normal brains interacted with the CK2α subunit, though the unglycosylated PrP seemed to have a stronger binding ability with CK2α subunit. The domain responsible for interacting with CK2α was located at the C-terminal segment of PrP (residues 91-231). This study proposed reliable experimental data for the molecular interaction between PrP and CK2α (both in recombinant and native categories), scientific clues for further assessing the potential biological significance of the PrP-CK2 interaction, and the possible role of CK2 in the pathogenesis of prion diseases.

  10. Casein Phosphopeptide-Amorphous Calcium Phosphate Reduces Streptococcus mutans Biofilm Development on Glass Ionomer Cement and Disrupts Established Biofilms.

    Science.gov (United States)

    Dashper, Stuart G; Catmull, Deanne V; Liu, Sze-Wei; Myroforidis, Helen; Zalizniak, Ilya; Palamara, Joseph E A; Huq, N Laila; Reynolds, Eric C

    2016-01-01

    Glass ionomer cements (GIC) are dental restorative materials that are suitable for modification to help prevent dental plaque (biofilm) formation. The aim of this study was to determine the effects of incorporating casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) into a GIC on the colonisation and establishment of Streptococcus mutans biofilms and the effects of aqueous CPP-ACP on established S mutans biofilms. S. mutans biofilms were either established in flow cells before a single ten min exposure to 1% w/v CPP-ACP treatment or cultured in static wells or flow cells with either GIC or GIC containing 3% w/w CPP-ACP as the substratum. The biofilms were then visualised using confocal laser scanning microscopy after BacLight LIVE/DEAD staining. A significant decrease in biovolume and average thickness of S. mutans biofilms was observed in both static and flow cell assays when 3% CPP-ACP was incorporated into the GIC substratum. A single ten min treatment with aqueous 1% CPP-ACP resulted in a 58% decrease in biofilm biomass and thickness of established S. mutans biofilms grown in a flow cell. The treatment also significantly altered the structure of these biofilms compared with controls. The incorporation of 3% CPP-ACP into GIC significantly reduced S. mutans biofilm development indicating another potential anticariogenic mechanism of this material. Additionally aqueous CPP-ACP disrupted established S. mutans biofilms. The use of CPP-ACP containing GIC combined with regular CPP-ACP treatment may lower S. mutans challenge.

  11. Casein kinase 1 alpha regulates chromosome congression and separation during mouse oocyte meiotic maturation and early embryo development.

    Science.gov (United States)

    Wang, Lu; Lu, Angeleem; Zhou, Hong-Xia; Sun, Ran; Zhao, Jie; Zhou, Cheng-Jie; Shen, Jiang-Peng; Wu, Sha-Na; Liang, Cheng-Guang

    2013-01-01

    Casein kinase I alpha (CK1α) is a member of serine/threonine protein kinase, generally present in all eukaryotes. In mammals, CK1α regulates the transition from interphase to metaphase in mitosis. However, little is known about its role in meiosis. Here we examined Ck1α mRNA and protein expression, as well as its subcellular localization in mouse oocytes from germinal vesicle to the late 1-cell stage. Our results showed that the expression level of CK1α was increased in metaphase. Immunostaining results showed that CK1α colocalized with condensed chromosomes during oocyte meiotic maturation and early embryo development. We used the loss-of-function approach by employing CK1α specific morpholino injection to block the function of CK1α. This functional blocking leads to failure of polar body 1 (PB1) extrusion, chromosome misalignment and MII plate incrassation. We further found that D4476, a specific and efficient CK1 inhibitor, decreased the rate of PB1 extrusion. Moreover, D4476 resulted in giant polar body extrusion, oocyte pro-MI arrest, chromosome congression failure and impairment of embryo developmental potential. In addition, we employed pyrvinium pamoate (PP), an allosteric activator of CK1α, to enhance CK1α activity in oocytes. Supplementation of PP induced oocyte meiotic maturation failure, severe congression abnormalities and misalignment of chromosomes. Taken together, our study for the first time demonstrates that CK1α is required for chromosome alignment and segregation during oocyte meiotic maturation and early embryo development.

  12. Casein kinase 1 alpha regulates chromosome congression and separation during mouse oocyte meiotic maturation and early embryo development.

    Directory of Open Access Journals (Sweden)

    Lu Wang

    Full Text Available Casein kinase I alpha (CK1α is a member of serine/threonine protein kinase, generally present in all eukaryotes. In mammals, CK1α regulates the transition from interphase to metaphase in mitosis. However, little is known about its role in meiosis. Here we examined Ck1α mRNA and protein expression, as well as its subcellular localization in mouse oocytes from germinal vesicle to the late 1-cell stage. Our results showed that the expression level of CK1α was increased in metaphase. Immunostaining results showed that CK1α colocalized with condensed chromosomes during oocyte meiotic maturation and early embryo development. We used the loss-of-function approach by employing CK1α specific morpholino injection to block the function of CK1α. This functional blocking leads to failure of polar body 1 (PB1 extrusion, chromosome misalignment and MII plate incrassation. We further found that D4476, a specific and efficient CK1 inhibitor, decreased the rate of PB1 extrusion. Moreover, D4476 resulted in giant polar body extrusion, oocyte pro-MI arrest, chromosome congression failure and impairment of embryo developmental potential. In addition, we employed pyrvinium pamoate (PP, an allosteric activator of CK1α, to enhance CK1α activity in oocytes. Supplementation of PP induced oocyte meiotic maturation failure, severe congression abnormalities and misalignment of chromosomes. Taken together, our study for the first time demonstrates that CK1α is required for chromosome alignment and segregation during oocyte meiotic maturation and early embryo development.

  13. Effects of gelation temperature on Mozzarella-type curd made from buffalo and cows' milk: 2. Curd yield, overall quality and casein fractions.

    Science.gov (United States)

    Hussain, Imtiaz; Yan, Jen; Grandison, Alistair S; Bell, Alan E

    2012-12-01

    The overall quality of Mozzarella-type curds made from buffalo and cows' milks were measured at gelation temperatures of 28, 34 and 39°C, and cutting times of 45, 60, 75 and 90min after chymosin addition. The curd yield and moisture content decreased with increasing gelation temperature, while whey fat losses increased. The effect of higher gelation temperature (39°C) was more pronounced in cows' milk than buffalo milk. This results in more fat losses and lower yields in both milk samples at a gelation temperature of 39°C. The minimum losses of fat and protein in rennet whey occurred at a gelation temperature of 34°C in both milk samples. The curd yield was higher in buffalo milk as compared to cows' milk. This is due to difference in total solids (fat and protein contents) of the two types of bovine milk. The different cutting times had a small effect on the yield and overall quality of curds made from both milk types. Curd moisture and loss tangent have a strong relationship with respect to effects of gelation temperature. Two different curd drainage methods (centrifugation and Buchner funnel filtration) were used to compare the final overall quality of Mozzarella-type curds made from both milk types. The α(s1) and β casein fractions were found to be in different proportions in the two milk types. The total- and casein bound-calcium were higher in buffalo milk than cows' milk. The total protein, casein and fat were also found to be higher in buffalo milk than cows' milk.

  14. Diffusing wave spectroscopy study of the colloidal interactions occurring between casein micelles and emulsion droplets: comparison to hard-sphere behavior.

    Science.gov (United States)

    Gaygadzhiev, Zafir; Corredig, Milena; Alexander, Marcela

    2008-04-15

    Understanding the underlying processes that govern interparticle interactions in colloidal systems is fundamental to predicting changes in their bulk properties. In this paper we discuss the colloidal behavior of casein micelles and protein-stabilized fat globules individually and in a mixture. The colloidal interactions were observed by transmission diffusing wave spectroscopy. The turbidity parameter, l*, and the diffusion coefficients of the samples studied were measured experimentally and compared to the theoretically calculated parameters for a hard-sphere system. The light scattering properties of casein micelles (volume fraction phi = 0.1-0.2) dispersed in milk permeate showed no deviation from the theoretically predicted model. Whey protein isolate (WPI)-stabilized emulsions (phi = 0.025-0.1) prepared either in milk permeate or in 5 mM imidazole buffer at pH 6.8 showed a behavior identical to that of the hard-sphere model. Similarly to the WPI-stabilized fat globules, the sodium caseinate (NaCas)-stabilized emulsions (phi = 0.025-0.1) prepared in milk permeate also showed resemblance to the theory. In contrast, NaCas-stabilized emulsions prepared in 5 mM imidazole buffer exhibited some discrepancy from the theoretically calculated parameters. The deviation from theory is attributed to the enhanced steric stabilization properties of these droplets in a low ionic strength environment. When recombined milks made from concentrated milk and WPI- and NaCas-stabilized droplets prepared in permeate (phi = 0.125-0.2) were studied, the experimental data showed a significant deviation from the theoretical behavior of a hard-sphere model due to mixing of two different species.

  15. CK2(beta)tes gene encodes a testis-specific isoform of the regulatory subunit of casein kinase 2 in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Kalmykova, Alla I; Shevelyov, Yuri Y; Polesskaya, Oksana O

    2002-01-01

    An earlier described CK2(beta)tes gene of Drosophila melanogaster is shown to encode a male germline specific isoform of regulatory beta subunit of casein kinase 2. Western-analysis using anti-CK2(beta)tes Ig revealed CK2(beta)tes protein in Drosophila testes extract. Expression of a CK2(beta...... and coimmunoprecipitation analysis of protein extract from Drosophila testes, we demonstrated an association between CK2(beta)tes and CK2alpha. Northern-analysis has shown that another regulatory (beta') subunit found recently in D. melanogaster genome is also testis-specific. Thus, we describe the first example of two...

  16. The Effect of Intrinsic Disorder and Self-association on the Translational Diffusion of Proteins: the Case of α-Casein.

    Science.gov (United States)

    Melnikova, Daria L; Skirda, Vladimir Dmitrievich; Nesmelova, Irina V

    2017-03-27

    Translational diffusion is the major mode of macromolecular transport in leaving organisms and therefore it is vital to many biological and biotechnological processes. Although translational diffusion of proteins has received considerable theoretical and experimental scrutiny, much of that attention has been directed towards the description of globular proteins. The translational diffusion of intrinsically disordered proteins (IDPs), however, is much less studied. Here, we use a pulsed-gradient nuclear magnetic resonance technique (PFG NMR) to investigate the translational diffusion of a disordered protein in a wide range of concentrations using α-casein that belongs to the class of natively disordered proteins as an example.

  17. Polymorphism of the CSN1S1 casein gene in position 663 in national sheep breeds and European mouflon (Ovis aries musimon)

    OpenAIRE

    Roman Niżnikowski; Grzegorz Czub; Krzysztof Głowacz; Marcin Świątek; Magdalena Ślęzak

    2013-01-01

    The study was carried out on the material of 1802 sheeps (1175♀ and 627♂) coming from European mouflon (Ovis aries musimon), its hybrids with Polish heat sheep, four sheep breeds that are characterised by a mixed wool, as well as Polish merino. All animals were subjected to the identification of the alpha-S1 casein gene – CSN1S1. On the basis of the research two alleles (C and T) were identified and three genotypes (CC, CT and TT). A balanced frequency of alleles C and T in ...

  18. THE EFFECT OF CASEIN HYDROLYSATES ON TRANSGLUTAMINASE PRODUCTION BY STRETOVERTICILLUM SK-2%酪蛋白水解物对轮枝链霉菌SK-1产谷氨酰胺转胺酶的影响

    Institute of Scientific and Technical Information of China (English)

    常中义; 江波; 王璋

    2001-01-01

    酪蛋白经胰酶水解后,可以被轮枝链霉菌SK-1所利用.采用pH-STAT法得到了DH=3、DH=6、DH=9、DH=12等4个水解度的酪蛋白水解物.当酪蛋白水解物作氮源时,其水解度(即肽相对分子质量的大小)对轮枝链霉菌SK-1产谷氨酰胺转胺酶酶影响很大,其中以DH=3的酪蛋白水解物效果最好,而且肽的浓度对轮枝链霉菌SK-1产谷胺酰胺转胺酶也有一定的影响,其中以4%的浓度最为合适.%After being hydrolyzing,casein was utilized by Stretoverticillium SK-2.Casein hydrolyzated (DH=3,DH=6,DH=9,DH=12)wer e obtained wit h pancreatin.When the casein hydrolyzates were used as a nitrogen source,the der gree of hydrolysis(the molecular weight of casein peptide)had a significant infl uence on the production of transglutaminae by Stretoverticillium SK- 2 and the op timum value was DH=3,The production of transglutaminase also depend on the c oncentration of casein peptide and,with 4% addition of DH=3 casein peptide,t he production of transglutaminase reached 3.89 u/mL.

  19. Cross-linking of Casein by Peroxidase and Modification in Emulsifying Properties%过氧化物酶催化酪蛋白的交联反应优化与乳化性改善

    Institute of Scientific and Technical Information of China (English)

    赵新淮; 李君文

    2009-01-01

    采用辣根过氧化物酶对酪蛋白进行酶促交联,并经SDS-聚丙烯酰胺凝胶电泳、光谱分析和毛细管电泳验证.利用毛细管电泳、面积归一化方法对交联酪蛋白进行分析并计算交联度;以交联度为指标、应用响应面分析法对交联条件优化,得出适宜的条件为:温度37℃、反应时间2.9 h、酶添加量为每克蛋白质4.73μkat,此条件下酪蛋白交联度达到6.9%.与酪蛋白相比,交联酪蛋白的乳化活性在蛋白质质量分数为0.01%时提高了8.7%,而其乳化稳定性在蛋白质质量分数为0.03%时提高了21.1%.%Cross-linking of casein catalyzed by horseradish peroxidase was studied, which was demonstrated by SDS-PAGE analysis, spectroscopic analysis and capillary electrophoresis analysis. The cross-linking degree of casein was measured by capillary electrophoresis with an area normalization method. Response surface method was applied to optimize the reaction conditions for cross-linked casein. The optimal cross-linking conditions obtained were that enzyme addition level was 4.73 μkat per gram protein, temperature was 37℃ and reaction time was 2.9 h. Under these optimal conditions, the cross-linking degree of casein prepared was about 6.9%. Evaluation results show that emulsifying activity index of cross-linked casein at concentration of 0.01% has an increase of 8.7%, while emulsifying stability index of cross-linked casein at concentration of 0.03 % has an increase of 21.1% comparing to that of native casein, which indicates the improvement in emulsifying properties of cross-linked casein.

  20. Discussing on the Qualitative and Quantitative Analysis of Soybean Protein Fiber and Casein Protein Fiber%大豆、牛奶纤维定性定量方法探讨

    Institute of Scientific and Technical Information of China (English)

    樊微; 李添琦

    2012-01-01

    In this article the indentification of soybean fiber and casein protein fiber by the method of microscope, burning and chemical dissolution was discussed. The content of soybean, casein protein fiber and other fibers of the blended fabric was also studied.%通过显微镜法、燃烧法以及化学溶解法,对大豆、牛奶纤维的鉴别进行了研究,并且对大豆、牛奶纤维与其他纤维混纺的织物进行了含量分析。

  1. Casein kinase II induced polymerization of soluble TDP-43 into filaments is inhibited by heat shock proteins.

    Directory of Open Access Journals (Sweden)

    Yari Carlomagno

    Full Text Available BACKGROUND: Trans-activation Response DNA-binding Protein-43 (TDP-43 lesions are observed in Amyotrophic Lateral Sclerosis (ALS, Frontotemporal Lobar Degeneration with ubiquitin inclusions (FTLD-TDP and 25-50% of Alzheimer's Disease (AD cases. These abnormal protein inclusions are composed of either amorphous TDP-43 aggregates or highly ordered filaments. The filamentous TDP-43 accumulations typically contain clean 10-12 nm filaments though wider 18-20 nm coated filaments may be observed. The TDP-43 present within these lesions is phosphorylated, truncated and ubiquitinated, and these modifications appear to be abnormal as they are linked to both a cellular heat shock response and microglial activation. The mechanisms associated with this abnormal TDP-43 accumulation are believed to result in a loss of TDP-43 function, perhaps due to the post-translational modifications or resulting from physical sequestration of the TDP-43. The formation of TDP-43 inclusions involves cellular translocation and conversion of TDP-43 into fibrillogenic forms, but the ability of these accumulations to sequester normal TDP-43 and propagate this behavior between neurons pathologically is mostly inferred. The lack of methodology to produce soluble full length TDP-43 and recapitulate this polymerization into filaments as observed in disease has limited our understanding of these pathogenic cascades. RESULTS: The protocols described here generate soluble, full-length and untagged TDP-43 allowing for a direct assessment of the impact of various posttranslational modifications on TDP-43 function. We demonstrate that Casein Kinase II (CKII promotes the polymerization of this soluble TDP-43 into 10 nm diameter filaments that resemble the most common TDP-43 structures observed in disease. Furthermore, these filaments are recognized as abnormal by Heat Shock Proteins (HSPs which can inhibit TDP-43 polymerization or directly promote TDP-43 filament depolymerization. CONCLUSION

  2. Effect of Temperature, pH, Enzyme to Substrate Ratio, Substrate Concentration and Time on the Antioxidative Activity of Hydrolysates from Goat Milk Casein by Alcalase

    Directory of Open Access Journals (Sweden)

    Shu Guowei

    2016-12-01

    Full Text Available The effect of hydrolysis temperature (45, 50, 55, 60 and 65°C, pH (7.0, 7.5, 8.0, 8.5 and 9.0, enzyme to substrate (E/S ratio (1.0, 1.5, 2.0, 2.5 and 3.0%, substrate concentration (2, 3, 4, 5 and 6% and hydrolysis time (30-240min on antioxidant peptides hydrolysated from goat’s milk casein by Alcalase was investigated using single factor experiment. In order to obtain high DPPH radical-scavenging activity, metal-chelating activity and superoxide radical scavenging activity, the optimal conditions were hydrolysis time of 150 min, temperature of 50°C, pH 8.0, E/S ratio of 2.0% and substrate concentration of 4.0%. The hydrolysis time, hydrolysis temperature, pH, E/S ratio and substrate concentration had a significant influence on degree of hydrolysis, metal-chelating activity, DPPH and superoxide radical scavenging activity on casein hydrolysate of goat milk by Alcalase, the results were beneficial for further provide theoretical basis for production of antioxidant peptides.

  3. Polymorphism of the CSN1s1 casein gene in position 663 in Polish lowland sheep breeds from the Podlasie region

    Directory of Open Access Journals (Sweden)

    Roman Niżnikowski

    2015-03-01

    Full Text Available The studies were conducted on 431 sheep (406♀ and 25♂ of three varieties of Polish lowland sheep: Żelazna sheep, corriedale sheep and Polish lowland sheep from the Podlasie region. All animals were subjected to the identification of the alpha-S1 casein gene – CSN1S1. On the basis of the research two alleles (C and T and three genotypes (CC, CT and TT were identified. A balanced frequency of alleles C and T in all investigated varieties was identified, which translated into a balanced distribution of genotypes: the T allele and the TT genotype occurred more frequently than C allele and CC and CT genotypes. There was significantly higher frequency of C allele and lower of T allele in ewes compared to rams in all studied varieties. The study concluded that in the frequency of alleles and genotypes of casein gene alpha-S1 in position 663 the genetic alignments in all three varieties of Polish lowland sheep were observed.

  4. Inhibition and Promotion of Heat-Induced Gelation of Whey Proteins in the Presence of Calcium by Addition of Sodium Caseinate.

    Science.gov (United States)

    Nguyen, Bach T; Balakrishnan, Gireeshkumar; Jacquette, Boris; Nicolai, Taco; Chassenieux, Christophe; Schmitt, Christophe; Bovetto, Lionel

    2016-11-14

    Heat-induced aggregation and gelation of aqueous solutions of whey protein isolate (WPI) in the presence of sodium caseinate (SC) and CaCl2 was studied at pH 6.6. The effect of adding SC (0-100 g/L) on the structure of the aggregates and the gels was investigated by light scattering and confocal laser scanning microscopy at different CaCl2 concentration ([CaCl2] = 0-30 mM). The gelation process was studied by oscillatory shear rheology. At the whey protein concentrations studied here (34 and 60 g/L), no gels were formed in the absence of CaCl2 and SC. However, WPI solutions gelled above a critical CaCl2 concentration that increased with increasing SC concentration. In the absence of CaCl2, WPI gels were formed only above a critical SC concentration. The critical SC concentration needed to induce WPI gelation decreased weakly when CaCl2 was added. In an intermediate range of CaCl2 concentrations, gels were formed both at low and high SC concentrations, but not at intermediate SC concentrations. Finally, at high CaCl2 concentrations gels were formed at all SC concentrations. The gelation rate and the gel structure of the gels formed at low and high casein concentrations were very different. The effect of SC on the thermal gelation of WPI was interpreted by competition for Ca(2+), a chaperon effect, and microphase separation.

  5. In silico, in vitro and in vivo analyses of dipeptidyl peptidase IV inhibitory activity and the antidiabetic effect of sodium caseinate hydrolysate.

    Science.gov (United States)

    Hsieh, Cheng-Hong; Wang, Tzu-Yuan; Hung, Chuan-Chuan; Jao, Chia-Ling; Hsieh, You-Liang; Wu, Si-Xian; Hsu, Kuo-Chiang

    2016-02-01

    The frequency (A), a novel in silico parameter, was developed by calculating the ratio of the number of truncated peptides with Xaa-proline and Xaa-alanine to all peptide fragments from a protein hydrolyzed with a specific protease. The highest in vitro DPP-IV inhibitory activity (72.7%) was observed in the hydrolysate of sodium caseinate by bromelain (Cas/BRO), and the constituent proteins of bovine casein also had relatively high A values (0.10-0.17) with BRO hydrolysis. 1CBR (the <1 kDa fraction of Cas/BRO) showed the greatest in vitro DPP-IV inhibitory activity of 77.5% and was used for in vivo test by high-fat diet-fed and low-dose streptozotocin-induced diabetic rats. The daily administration of 1CBR for 6 weeks was effective to improve glycaemic control in diabetic rats. The results indicate that the novel in silico method has the potential as a screening tool to predict dietary proteins to generate DPP-IV inhibitory and antidiabetic peptides.

  6. Application of Humidity-Controlled Dynamic Mechanical Analysis (DMA-RH to Moisture-Sensitive Edible Casein Films for Use in Food Packaging

    Directory of Open Access Journals (Sweden)

    Laetitia M. Bonnaillie

    2015-01-01

    Full Text Available Protein-based and other hydrophilic thin films are promising materials for the manufacture of edible food packaging and other food and non-food applications. Calcium caseinate (CaCas films are highly hygroscopic and physical characterization under broad environmental conditions is critical to application development and film optimization. A new technology, humidity-controlled dynamic mechanical analysis (DMA-RH was explored to characterize CaCas/glycerol films (3:1 ratio during isohume temperature (T ramps and steps, and isothermal RH ramps and steps, to determine their mechanical and moisture-sorption properties during extensive T and RH variations. When RH and/or T increased, CaCas/Gly films became strongly plasticized and underwent several primary and secondary humidity-dependent transition temperatures (or transition humidities; the CaCas/Gly network hypothetically rearranged itself to adapt to the increased water-content and heat-induced molecular mobility. Between 5–40 °C and 20%–61% RH, moisture-sorption was rapid and proportional to humidity between transition points and accelerated greatly during transitions. CaCas/Gly films seemed unsuitable for storage or utilization in warm/humid conditions as they lost their mechanical integrity around Tm ~ 40 °C at 50% RH and Tm decreased greatly with increased RH. However, below Tm, both moisture- and heat-induced structural changes in the films were fully reversible and casein films may withstand a variety of moderate abuse conditions.

  7. Effect of casein-based semi-synthetic food on renal acid excretion and acid-base state of blood in dogs.

    Science.gov (United States)

    Zijlstra, W G; Langbroek, A J; Kraan, J; Rispens, P; Nijmeijer, A

    1995-01-01

    Urinary acid excretion and blood acid-base state were determined in dogs fed a casein-based semi-synthetic food (SSF), to which different amounts of salts had been added, in comparison with feeding normal dog food. Net acid excretion (NAE) and inorganic acid excretion (IAE) increased during SSF feeding. IAE was higher than the acid load calculated from the sulphur and phosphorus content of the casein. This higher IAE appeared to be due to the presence of calcium and magnesium phosphate in the diet, because calcium and magnesium may be in part precipitated as carbonate, leaving phosphate to be absorbed as phosphoric acid. Acid excretion decreased by addition of CaO. When no neutral Na+ and K+ salts were added, the increase in NAE was accompanied by a metabolic acidosis. K+ was more effective in attenuating the acidosis than Na+. On the basis of these findings a diet can be made which imposes a known acid load, and provides stable baseline values. Hence, any additions that influence the acid-base balance can be properly studied. The data obtained in these and future studies utilising this diet may be of help in optimising the composition of nutrient solutions to be used in the care of critically ill patients.

  8. Polymorphism of the CSN1S1 casein gene in position 663 in national sheep breeds and European mouflon (Ovis aries musimon

    Directory of Open Access Journals (Sweden)

    Roman Niżnikowski

    2013-12-01

    Full Text Available The study was carried out on the material of 1802 sheeps (1175♀ and 627♂ coming from European mouflon (Ovis aries musimon, its hybrids with Polish heat sheep, four sheep breeds that are characterised by a mixed wool, as well as Polish merino. All animals were subjected to the identification of the alpha-S1 casein gene – CSN1S1. On the basis of the research two alleles (C and T were identified and three genotypes (CC, CT and TT. A balanced frequency of alleles C and T in European mouflon were identified, which translated into a balanced distribution of genotypes, in contrast to the other groups, in which the T allele and the TT genotype decidedly had most of the frequency compared to C allele and CC and TC genotypes. It was shown that in the European mouflon CC genotype appeared in the highest proportion in comparison to the other groups, of which only Polish heat sheep and Polish mountain sheep – white were characterised by the participation of trace conditioning. It was concluded that the studies proved that the process of domestication may have a significant impact on the quantity and distribution of alleles and genotypes in the alpha-S1 casein gene. This result indicates the need for further research in this area in “cultural” sheep (e.g. compared to the Polish merino, characterised by a more specialised usability (e.g. meat or wool-meat.

  9. Comparison of energy supplements during prolonged exercise for maintenance of cardiac function: carbohydrate only versus carbohydrate plus whey or casein hydrolysate.

    Science.gov (United States)

    Oosthuyse, Tanja; Millen, Aletta M E

    2016-06-01

    Cardiac function is often suppressed following prolonged strenuous exercise and this may occur partly because of an energy deficit. This study compared left ventricular (LV) function by 2-dimensional echocardiography and tissue Doppler imaging (TDI) before and after ∼2.5 h of cycling (2-h steady-state 60% peak aerobic power output plus 16 km time trial) in 8 male cyclists when they ingested either placebo, carbohydrate-only (CHO-only), carbohydrate-casein hydrolysate (CHO-casein), or carbohydrate-whey hydrolysate (CHO-whey). No treatment-by-time interactions occurred, but pre-to-postexercise time effects occurred selectively. Although diastolic function measured by pulsed-wave Doppler early-to-late (E/A) transmitral blood flow velocity was suppressed in all trials from pre- to postexercise (mean change post-pre exercise: -0.53 (95% CI -0.15 to -0.91)), TDI early-to-late (e'/a') tissue velocity was significantly suppressed pre- to postexercise only with placebo, CHO-only, and CHO-whey (septal and lateral wall e'/a' average change: -0.62 (95% CI -1.12 to -0.12); -0.69 (95% CI -1.19 to -0.20); and -0.79 (95% CI -1.28 to -0.29), respectively) but not with CHO-casein (-0.40 (95% CI -0.90 to 0.09)). LV contractility was, or tended to be, significantly reduced pre- to postexercise with placebo, CHO-only, and CHO-whey (systolic blood pressure/end systolic volume change, mm Hg·mL(-1): -0.8 (95% CI -1.2 to -0.4), p = 0.0003; -0.5 (95% CI -0.9 to -0.02), p = 0.035; and -0.4 (95% CI -0.8 to 0.04), p = 0.086, respectively), but not with CHO-casein (-0.3 (95% CI -0.8 to 0.1), p = 0.22). However, ejection fraction (EF) and ventricular-arterial coupling were significantly reduced pre- to postexercise only with placebo (placebo change: EF, -4.6 (95% CI -8.4 to -0.7)%; stroke volume/end systolic volume, -0.3 (95% CI -0.6 to -0.04)). Despite no treatment-by-time interactions, pre-to-postexercise time effects observed with specific beverages may be meaningful for athletes

  10. Establishing relationship between hydrophobicity and emulsification of caseins using generalized-regression-neural-network%采用广义回归神经网络建立酪蛋白乳化性与疏水性关系

    Institute of Scientific and Technical Information of China (English)

    杨敏; 张克平; 王江鱼; 杨继涛; 杨晰

    2014-01-01

    为了研究琥珀酰化修饰后酪蛋白乳化性与疏水性关系,该文以琥珀酰化牦牛乳酪蛋白为研究对象,分析了不同酰化程度酪蛋白乳化性及疏水性变化趋势,采用广义回归神经网络建立了牦牛乳酰化酪蛋白乳化性与疏水性关系模型。结果显示,琥珀酰化牦牛乳酪蛋白乳化性和疏水性均与酰化程度、pH值有关,pH值为5以上,随着酰化程度的增加,酪蛋白乳化活性增大;等电点附近,酪蛋白乳化活性较差,等电点之后乳化活性迅速增大。pH值介于2-6时,所有酪蛋白乳化稳定性较强,pH值介于6-11之间时,酪蛋白乳化稳定性差异较小,pH值为12时乳化稳定性有所增加。酪蛋白内荧光与1-苯胺基萘-8-磺酸(1-aniline napthalene-8-sulfonic acid, ANS)外源荧光最大荧光强度和最大发射波长随酰化程度及 pH 值变化表现出较为复杂的关系。通过广义回归神经网络(generalized-regression-neu-network,GRNN)建立了牦牛乳酪蛋白疏水性参数、pH值、酰化程度与乳化性关系,网络模型对乳化性的预测相对误差小于10%,预测结果良好。研究结果为酪蛋白乳化性研究提供了参考依据。%Yaks (Bos grunniens) from the Qinghai-Tibetan plateau are the sole source of milk of local inhabitants. In the past years, yak milk has attracted more and more attention, due to its increasing demand. Yak milk is widely used to produce butter, soft and hard cheeses, yogurt, milk powder, Qula, and casein-containing products. Caseins, the major protein in milk, are commonly used in the food, chemical, cosmetic, and pharmaceutical industries. Yak caseins are widely used to produce high quality food ingredients and soaps, glues, leather polishing reagents, and clothing, among others. However, compared to cow caseins, yak caseins have poor solubility, which affects the other functional properties. The poor solubility of yak caseins is mostly

  11. 氧化酪蛋白对小鼠组织抗氧化能力及血液肽组成的影响%Effects of Oxidized Casein on Antioxidant Capacity and Plasma Peptide Composition in Mice

    Institute of Scientific and Technical Information of China (English)

    吴伶艳; 李竹青; 吴秋萍; 乐国伟; 施用晖

    2011-01-01

    Objective To investigate the effects of casein modified by the heating and lipid peroxidation product MDA on the redox state and the peptide composition of plasma in mice. Methods Casein was heated at 100% for different time(0,30,60,90 min),oxidized by different doses of MDA (0,0. 2,20. 0,200.0 mmol/L). The variation on carbonyl content, free thiol groups, surface hydrophobieity of casein were measured in vitro. The mice were divided into four groups: ig normal saline, normal casein, heating oxidated casein and MDA oxidated casein. The production of free radical (FR) in mice blood were detected respectively at 0,30,60,90,120,160 min after administration. The plasma peptides were detected by HPLC-MS.The redox-related indicators(T-AOC,MDA,GSH)in liver,Jejunum,Duodenum were determined. Results The carbonyl content of casein increased while free thiol groups content decreased with casine modified by MDA concentration or heating. The surface hydrophobieity was lower in heated casein than that of normal casein,but higher in MDA oxidized casein. The FR peak of blood appeared at 160 min. The blood FR was significantly higher in mice administered oxidized casein than that of normal casein. The T-AOC^GSH content of liver, jejunum and duodenum decreased while MDA increased in mice ig with oxidized casein. HPLC-MS analysis showed that composition of plasma peptides were different in the plasma of mice ig MDA oxidized casein group with nomal casein,new C7Hi5 N4O substances containing carbonyl appeared in plasma. Conclusion The oxidation will lead to changes in physical and chemical properties of casein. The intake of the oxidated casein can cause a high oxidative stress in mice and fragments of oxidized protein hydrolyzote appeared in blood.%目的研究酪蛋白经过加热氧化和脂质过氧化物MDA氧化后,对小鼠体内氧化还原状态及小鼠血液中肽组成的影响。方法酪蛋白经l00℃加热(0、30、60、90min)和丙二醛(MDA)氧化(MDA终浓度0、0

  12. The preliminary study on the effects of growth hormone and insulin-like growth factor-I on κ-casein synthesis in bovine mammary epithelial cells in vitro.

    Science.gov (United States)

    Wang, M Z; Ji, Y; Wang, C; Chen, L M; Wang, H R; Loor, J J

    2016-04-01

    The effects of growth hormone (GH) and insulin-like growth factor-I (IGF-I) on protein synthesis and gene expression of κ-casein in bovine mammary epithelial cell in vitro were studied. The treatments were designed as follows: the growth medium without serum was set as the control group, while the treatments were medium supplemented with GH (100 ng/ml), IGF-I (100 ng/ml), and GH (100 ng/ml) + IGF-I (100 ng/ml). The quantity of κ-casein protein was measured by ELISA, and the κ-casein gene (CSN3) expression was examined by real-time quantitative PCR (RT-qPCR). Compared with the control group, all the experimental groups had greater (p  0.05). Furthermore, no synergistic effect of GH and IGF-I was observed for both the κ-casein concentration and CSN3 expression. It is therefore concluded that GH or IGF-I can independently promote the expression of CSN3 in bovine mammary epithelial cells in vitro.

  13. Pilot scale production process of micellar casein concentrate powder%酪蛋白胶束粉的陶瓷膜分离生产工艺

    Institute of Scientific and Technical Information of China (English)

    陈建行; 刘鹭; 孙颜君; 苏燕玲; 张书文; 孔凡丕; 蒋士龙; 吕加平

    2013-01-01

      为尽快建立酪蛋白胶束粉(micellar casein concentrate, MCC)的中试生产线,实现MCC在国内的工业化生产,该研究通过测定牛乳蛋白粒径,选取孔径40和100 nm的中空纤维陶瓷膜进行膜分离效果的对比,并选用膜分离效果较佳的陶瓷膜进行最佳操作参数的确定及稀释过滤工艺的研究,最后将自制MCC和进口MCC进行品质特性对比并分析其工业化生产的可能性。结果表明:孔径40 nm中空纤维陶瓷膜与孔径100 nm中空纤维陶瓷膜相比,渗透液中不含酪蛋白,能够减少酪蛋白损失,更适合于酪蛋白和乳清蛋白的分离,孔径40nm中空纤维陶瓷膜的最佳操作参数为操作压力2×105 Pa,料液温度50℃;采用四段式的连续稀释过滤工艺,可使料液中酪蛋白占真蛋白的比例从69.39%提升至93.34%,真蛋白占干物质的比例从38.45%提升至88.15%;稀释过滤完毕后膜的纯水通量衰减了39.98%,经生物酶清洗液清洗后膜的纯水通量恢复至初始的98.02%;自制MCC在成分组成上与加拿大Proteinco公司生产的MCC相比差异不显著(p<0.05),但在溶解度和粉粒的微观形态上优于Proteinco MCC;生产1 kg MCC需要原料乳46.24 L,成本为244.58元,可实现其国内工业化生产。研究结果为实现MCC在国内工业化生产及其应用性研究提供参考。%Micellar casein concentrate (MCC) powder, a new milk protein product produced by a combination of processes including membrane separation, evaporation and spray drying has potential applications in cheese making, whipped topping, coffee whitener and yogurt making. It is becoming more and more popular in the food processing industry, but currently China depends on imported MCC mainly from developed countries. The main objective of this study was to successfully develop a pilot scale production process for micellar casein concentrate powder and facilitate its rapid adoption and

  14. Antimicrobial effectiveness of bioactive packaging materials from edible chitosan and casein polymers: assessment on carrot, cheese, and salami.

    Science.gov (United States)

    Moreira, Maria del Rosario; Pereda, Mariana; Marcovich, Norma E; Roura, Sara I

    2011-01-01

    Antimicrobial packaging is one of the most promising active packaging systems for controlling spoilage and pathogenic microorganisms. In this work, the intrinsic antimicrobial properties of chitosan (CH) were combined with the excellent thermoplastic and film-forming properties of sodium caseinate (SC) to prepare SC/CH film-forming solutions and films. The antimicrobial effectiveness of SC, CH, and SC/CH coatings on the native microfloras of cheese, salami, and carrots was evaluated. In vitro assays through the test tube assay indicated that the most significant antimicrobial effect was achieved by CH and SC/CH solutions on carrot and cheese native microfloras. SC film-forming solutions did not exert antimicrobial activity on any of the native microflora studied. SC, CH, and SC/CH films stored in controlled environments showed that the retention of the antimicrobial action was observed until 5-d storage, at 65% relative humidity in both temperatures (10 °C and 20 °C). In vivo assays were also performed with SC, CH, and SC/CH applied as coatings or wrappers on the 3 food substrates. CH and SC/CH applied at both immersion and wrapper exerted a significant bactericidal action on mesophilic, psychrotrophic, and yeasts and molds counts, showing the 3 microbial populations analyzed a significant reduction (2.0 to 4.5 log CFU/g). An improvement of the bactericidal properties of the CH/SC blend respect to those of the neat CH film is reported. The ionic interaction between both macromolecules enhances its antimicrobial properties. Practical Application: The continuous consumer interest in high quality and food safety, combined with environmental concerns has stimulated the development and study of biodegradable coatings that avoid the use of synthetic materials. Among them, edible coatings, obtained from generally recognized as safe (GRAS) materials, have the potential to reduce weight loss, respiration rate, and improve food appearance and integrity. They can be used in

  15. Genetic variation and posttranslational modification of bovine κ-casein: effects on caseino-macropeptide release during renneting.

    Science.gov (United States)

    Jensen, Hanne B; Pedersen, Katrine S; Johansen, Lene B; Poulsen, Nina A; Bakman, Mette; Chatterton, Dereck E W; Larsen, Lotte B

    2015-02-01

    Chymosin-induced cleavage of κ-casein (κ-CN) occurs during the first enzymatic phase in milk coagulation during cheese manufacturing, where the hydrophilic C-terminal peptide of κ-CN, named caseino-macropeptide (CMP), is released into the whey. The CMP peptide is known for its rather heterogeneous composition with respect to both genetic variation and multiple posttranslational modifications, including phosphorylation and O-linked glycosylation. An approach of liquid chromatography coupled with mass spectrometry was used to investigate (1) the overall protein profile and (2) the release of various forms of CMP after addition of chymosin to individual cow milk samples from 2 breeds, Danish Jersey (DJ) and Danish Holstein-Friesian (DH). The cows were selected to represent distinct homo- and heterozygous types of the κ-CN genetic variants A, B, and E (i.e., genotypes AA, BB, AB, EE, and AE). Initially, investigation of the protein profile showed milk with κ-CN BB exhibited the highest relative content of κ-CN, whereas AE milk exhibited the lowest, and after 40min of renneting >90% of intact κ-CN was hydrolyzed by chymosin in milk representing all κ-CN genotype. By in-depth analysis of the CMP chromatographic profile, multiple CMP isoforms with 1 to 3 O-linked glycans (1-3 G) and 1 to 3 phosphate groups (1-3 P) were identified, as well as nonmodified CMP isoforms. The number of identified CMP isoforms varied to some extent between breeds (21CMP isoforms identified in DJ, 26CMP isoforms in DH) and between κ-CN genetic variants (CMP variant A being the most heterogeneous compared with CMP B and E), as well as between individual samples within each breed. The predominant forms of glycans attached to CMP were found to be the acidic tetrasaccharide {N-acetyl-neuraminic acid α(2-3)galactose β(1-3)[N-acetyl-neuraminic acid α(2-6)]N-acetyl galactose} or trisaccharides {N-acetyl-neuraminic acid α(2-3)galactose β(1-3)N-acetyl galactose and galactose β(1-3)[N

  16. Effects of soluble milk protein or casein supplementation on muscle fatigue following resistance training program: a randomized, double-blind, and placebo-controlled study

    Science.gov (United States)

    2014-01-01

    Background The effects of protein supplementation on muscle thickness, strength and fatigue seem largely dependent on its composition. The current study compared the effects of soluble milk protein, micellar casein, and a placebo on strength and fatigue during and after a resistance training program. Methods Sixty-eight physically active men participated in this randomized controlled trial and underwent 10 weeks of lower-body resistance training. Participants were randomly assigned to the Placebo (PLA), Soluble Milk Protein (SMP, with fast digestion rate) or Micellar Casein (MC, with slow digestion rate) group. During the 10-week training period, participants were instructed to take 30 g of the placebo or protein twice a day, or three times on training days. Tests were performed on quadriceps muscles at inclusion (PRE), after 4 weeks (MID) and after 10 weeks (POST) of training. They included muscle endurance (maximum number of repetitions during leg extensions using 70% of the individual maximal load), fatigue (decrease in muscle power after the endurance test), strength, power and muscle thickness. Results Muscle fatigue was significantly lower (P < 0.05) in the SMP group at MID and POST (-326.8 ± 114.1 W and -296.6 ± 130.1 W, respectively) as compared with PLA (-439.2 ± 153.9 W and -479.2 ± 138.1 W, respectively) and MC (-415.1 ± 165.1 W and -413.7 ± 139.4 W, respectively). Increases in maximal muscle power, strength, endurance and thickness were not statistically different between groups. Conclusions The present study demonstrated that protein composition has a large influence on muscular performance after prolonged resistance training. More specifically, as compared with placebo or micellar casein, soluble milk protein (fast digestible) appeared to significantly reduce muscle fatigue induced by intense resistance exercise. PMID:25057266

  17. β-酪蛋白淀粉样纤维沉淀的形成及影响因素%Amyloid Fibril Formation by β-Casein and Its Influence Factor

    Institute of Scientific and Technical Information of China (English)

    刘继华; John A.Carver; David C.Thorn

    2014-01-01

    β-Casein is the second abundant among the casein proteins in bovine milk and reported to exhibite biological activities. In this study, the focus was placed on the influence of lipids and heparin sulphate toβ-casein fibril formation. In order to study the time course of fibril formation byβ-casein, the samples were in-cubated and picked up at specific times and tested by ThT assay and transmission electron microscopy. The re-sults showed that amyloid fibrils were not formed byβ-casein incubated in pH=5. 4—9. 0 at 65 ℃ for 252 h, which suggested that β-casein is a good molecular chaperone. The β-casein fibril formation was promoted in the presence of longer-chain phosphatidylcholine lipids(D6PC and D9PC), which indicated that the interac-tion of β-casein with biomembrane of mammary gland abundant with lipids maybe caused β-casein structure changed from native to more β-sheet. Heparin sulphate, a major component of the extracellular matrix and a species which is commonly associated with extracellular amyloid deposits, interacted with β-casein to promote its aggregation. It is supposed that Corpora Amylacea is associated with mastitis because of high expression of heparin sulphate in inflamed mammary. This study explored that it is possible for chaperon proteins to form amyloid fibrils influenced by components in vivo and lose its chaperon effects.%利用硫磺素T( ThT)荧光分析法和透射电子显微镜检测β-酪蛋白形成淀粉样纤维沉淀( Fibril)的动力学过程,研究了磷脂和硫酸肝素对其 Fibril 形成的影响.实验结果表明,β-酪蛋白在65℃下, pH 值为5.4~9.0的范围内,加热252 h以上,并未形成Fibril,说明β-酪蛋白是一种很好的分子伴侣,在高温、弱酸和弱碱条件下均不形成淀粉样纤维沉淀.甘油磷酸胆碱D6PC和D9PC可以显著地促进β-酪蛋白的Fibril的形成,说明一定条件下蛋白质可能与细胞膜之间存在相互作用而导致其二级构象的转变.硫酸

  18. Effect of LPS on NF-κB, ACCα and β-Casein mRNA expression in mammary glands of mice%LPS对小鼠乳腺组织中NF-κB、ACCα和β-Casein mRNA表达的影响

    Institute of Scientific and Technical Information of China (English)

    侯瑛倩; 陶慧; 常广军; 林晶晶; 沈向真

    2014-01-01

    为探讨灌注不同质量浓度LPS对小鼠乳腺组织中NF-κB、ACCα和β-Casein mRNA表达的影响,选择30只雌性ICR小鼠为试验动物,受孕后随机分为试验组和对照组,试验组经第4对乳头灌注不同质量浓度LPS (0.1,5,10,50,100 mg/L),对照组灌注生理盐水,于灌注后6h采集乳腺组织样品,组织学方法分析乳腺组织的病理变化;采用RT-PCR方法分析乳腺组织中NF-κB、ACCα和β-Casein mRNA表达的变化.病理切片结果显示,随着LPS灌注浓度的增加,乳腺小叶间炎性细胞数量逐步增加,乳腺小叶内腺泡结构破坏程度也变大;对乳腺组织中NF-κB、ACCα和β-Casein的mRNA表达水平进行分析时,发现灌注LPS小鼠乳腺组织中NF-κB mRNA的表达水平随着LPS灌注浓度的增加而逐步增加,而ACCα和β-Casein mRNA的表达水平则随着LPS灌注浓度的增加而逐步降低.结果表明,灌注LPS能够上调NF-κB mRNA的表达,下调ACCα和p-CaseinmRNA的表达.

  19. Process for producing α-lactalbumin-enriched whey and evaluation of functional properties of rennet casein%α-乳白蛋白提取工艺研究及副产物功能性质评价

    Institute of Scientific and Technical Information of China (English)

    闫序东; 王彩云; 云战友; 尹睿杰

    2011-01-01

    研究了热附聚法结合凝乳酶处理从牛乳中直接提取α-乳白蛋白的工艺,得到富含α-乳白蛋白的乳清和副产物--附聚β-乳清蛋白的凝乳酶干酪素.富含α-乳白蛋白的乳清中α-乳白蛋白与β-乳球蛋白的浓度比达到3.03.达到了商业化产品的水平.副产物--附聚β-乳清蛋白的凝乳酶干酪素与市售凝乳酶干酪素在溶解性、持水性和乳化性方面存在的差异较小,将附聚β-乳清蛋白的凝乳酶干酪素作为原料应用于仿真干酪中,质构测定结果未显示出在质构方面与普通凝乳酶干酪素对照样品存在明显差异.%A process for producing α-lactalbumin-enriched fraction from milk was investigated. The process involved heating pH-adjusted skim milk and rennet treatment. The ratio of the concentration of α-lactalbumin to β-lactoglobulin was high enough to meet the level of commercial products. In addition to α-lactalbumin-enriched whey, rennet casein complex with whey proteins was obtained. The difference of solubility,water-holding capacity and emulsifying capacity between the casein/whey proteins aggregates and normal rennet casein were small and no obvious differences of texture of cheese analogue made of the casein/whey proteins aggregates and normal rennet casein were found.

  20. Optimization of rennet coagulation technology in the process of production of rennet casein%酶凝干酪素生产过程中酶凝工艺的优化

    Institute of Scientific and Technical Information of China (English)

    刘佳; 李青; 赵秀明; 赵征

    2012-01-01

    The effect of the amount of rennet added, rennet coagulation temperature and time on the technology of rennet casein were studied. The optimal rennet coagulation processing parameters of the production of rennet casein were determined by sensory evaluation on the process of coagulation. The results showed that the coagulation temperature and time have a significant effect on rennet coagulation status of rennet casein production. The optimal conditions of rennet coagulation were: the addition of rennet was 0.078%, the temperature of coagulation was 32 ℃ and coagulation time was 28 min. The physicochemical properties of rennet casein produced under this condition were similar to those of commercial rennet casein.%研究了凝乳酶添加量、凝乳温度和凝乳时间对酶凝干酪素酶凝工艺的影响,通过对凝乳过程的感官评价,最终确定了酶凝干酪素的最佳酶凝工艺参数.结果表明:凝乳温度和凝乳时间对酶凝干酪素酶凝状态有显著影响,确定最优工艺条件为:凝乳酶添加量的体积分数为0.078%,凝乳温度为32℃,凝乳时间28 min.此条件下生产的酶凝干酪素与市售酶凝干酪素理化指标接近.

  1. The casein genes in goat breeds from different Continents: analysis by Polymerase Chain Reaction – Single Strand Conformation Polymorphism (PCR-SSCP

    Directory of Open Access Journals (Sweden)

    A. Caroli

    2010-04-01

    Full Text Available A screening of casein gene variability was carried out by Polymerase Chain Reaction – Single Strand Conformation Polymorphism in 8 goat breeds from Sudan (Nubian goat, Turkey (Angora Goat Lalahan Tiftic, Angora Goat Yerkoy, Hair goat and India (Jammu, Maharashtra, Rajasthan, South Goat. A total of 16 different alleles or groups of alleles were found, showing conspicuous differences among breeds. The allele frequencies were submitted to cluster analysis in order to highlight differences between breeds, also including data from Red Sokoto, West African Dwarf Nigeria, West African Dwarf Cameroon, and Borno Goat. The tree obtained from the cluster analysis showed two main lineages. The West African goat clustered together, the Indian and Turkish breeds were in the other group. Nubian goat was found in an intermediate position.

  2. Effect of molecular weight on the transepithelial transport and peptidase degradation of casein-derived peptides by using Caco-2 cell model.

    Science.gov (United States)

    Wang, Bo; Li, Bo

    2017-03-01

    The transepithelial transport routes of casein-derived peptides with different molecular weights (MWs) were investigated using a Caco-2 cell monolayer. The peptidase hydrolysis during transport was also studied. The results indicate that the paracellular route was the main pathway for F1 (1600-1300Da) and F2 (1000-500Da), and the bioavailabilities were 10.66% and 9.54%, respectively. Peptidase hydrolysis results reveal that brush-border peptidases (BBPs) as well as some other peptidases were responsible for peptide degradation in the paracellular route. The maximum hydrolysis rate of the former was 6.91 and 5.59μM Gly/min for the latter. However, PepT1 was involved in the transport of F3 (transport and the maximum hydrolysis rate was 11.4μM Gly/min. Furthermore, we found that the amino acid sequence of di- and tripeptides might affect their bioavailabilities significantly.

  3. Preventive effect of feeding high-risk infants a casein hydrolysate formula or an ultrafiltrated whey hydrolysate formula. A prospective, randomized, comparative clinical study

    DEFF Research Database (Denmark)

    Halken, S; Høst, A; Hansen, L G

    1993-01-01

    In a prospective study of a 1-year birth cohort of 158 high-risk infants the effect of feeding breastmilk, a casein hydrolysate (Nutramigen) or a new ultrafiltrated whey hydrolysate (Profylac) on the development of cow milk protein allergy/intolerance (CMPA/CMPI) was assessed and compared. All...... period this regimen was combined with avoidance of solid foods and cow milk protein. All mothers had unrestricted diets and were encouraged to do breastfeeding only. Moreover, avoidance of daily exposure to tobacco smoking, furred pets and dust-collecting materials in the bedroom was advised. The infants....... None of the infants showed reactions against Nutramigen or Profylac. In 4 infants symptoms were provoked by breastmilk when the mother ingested cow milk and in 1 only by cow milk.(ABSTRACT TRUNCATED AT 250 WORDS)...

  4. Effect of fluoridated casein phospopeptide-amorphous-calcium phosphate complex, chlorhexidine fluoride mouthwash on shear bond strength of orthodontic brackets: A comparative in vitro study

    Directory of Open Access Journals (Sweden)

    C A Abdul Shahariyar

    2016-01-01

    Full Text Available Objective: The aim of the current study was to determine the effects of casein phosphopeptide amorphous calcium-phosphate (CPP-ACP complex, chlorhexidine fluoride mouthwash on shear bond strengths (SBSs of orthodontic brackets. Materials and Methods: About sixty extracted healthy human premolar teeth with intact buccal enamel were divided into two equal groups to which brackets were bonded using self-etching primers (SEPs and conventional means respectively. These were further equally divided into three subgroups - (1 control (2 CPP-ACP (3 chlorhexidine fluoride mouthwash. The SBSs were then measured using a universal testing machine. Results: SBS of the conventional group was significantly higher than the self-etching group. The intragroup differences were statistically insignificant. Conclusion: CPP-ACP, chlorhexidine fluoride mouthwash did not adversely affect SBS of orthodontic brackets irrespective of the method of conditioning. Brackets bonded with conventional technique showed greater bond strengths as compared to those bonded with SEP.

  5. Construction of transgenic mice producing CAT to milk by co-injection of two overlapping fragments of bovine αs1-casein-CAT gene

    Institute of Scientific and Technical Information of China (English)

    劳为德; 刘伟; 成国祥; 徐少甫; 成勇

    1996-01-01

    Two αs1-casein/chloramphenicol acetyltransferase (CAT) gene constructs overlapping by 3.0kb were constructed and co-injected into murine zygotes. In 9 of 10 lines of transgenic mice obtained, based on analysis of structure and expression of the transgene, accurate extrachromosomal homologous recombination (ECR) between the two overlapping DNA fragments was found. Different levels of CAT activity were detected in milk from these lines. The highest CAT activity was about 25-50μg/mL milk. In some mice. CAT activity was found in salvia gland, thymus and spleen extracts. The high frequency and accuracy of ECR reported here will be applicable in the experimental manipulation for generation of relatively large transgene.

  6. Antimicrobial Activity of Nisin and Natamycin Incorporated Sodium Caseinate Extrusion-Blown Films: A Comparative Study with Heat-Pressed/Solution Cast Films.

    Science.gov (United States)

    Colak, Basak Yilin; Peynichou, Pierre; Galland, Sophie; Oulahal, Nadia; Prochazka, Frédéric; Degraeve, Pascal

    2016-05-01

    Antimicrobial edible films based on sodium caseinate, glycerol, and 2 food preservatives (nisin or natamycin) were prepared by classical thermomechanical processes. Food preservatives were compounded (at 65 °C for 2.5 min) with sodium caseinate in a twin-screw extruder. Anti-Listeria activity assays revealed a partial inactivation of nisin following compounding. Thermoplastic pellets containing food preservatives were then used to manufacture films either by blown-film extrusion process or by heat-press. After 24 h of incubation on agar plates, the diameters of K. rhizophila growth inhibition zones around nisin-incorporated films prepared by solution casting (control), extrusion blowing or heat pressing at 80 °C for 7 min of nisin-containing pellets were 15.5 ± 0.9, 9.8 ± 0.2, and 8.6 ± 1.0 mm, respectively. Since heat-pressing for 7 min at 80 °C of nisin-incorporated pellets did not further inactivate nisin, this indicates that nisin inactivation during extrusion-blowing was limited. Moreover, the lower diameter of the K. rhizophila growth inhibition zone around films prepared with nisin-containing pellets compared to that observed around films directly prepared by solution casting confirms that nisin inactivation mainly occurred during the compounding step. Natamycin-containing thermoplastic films inhibited Aspergillus niger growth; however, by contrast with nisin-containing films, heat-pressed films had higher inhibition zone diameters than blown films, therefore suggesting a partial inactivation of natamycin during extrusion-blowing.

  7. Growth-promoting Activity of Casein Hydrolysate for Lactic Acid Bacteria%酪蛋白水解物对乳酸菌的促生长作用

    Institute of Scientific and Technical Information of China (English)

    张清丽; 赵强忠; 赵谋明

    2011-01-01

    研究了酪蛋白的木瓜蛋白酶水解物对乳酸菌(嗜热链球菌∶保加利亚杆菌=1∶1)的促生长作用.通过比较不同水解度的酪蛋白水解物的增值作用,发现酪蛋白经木瓜蛋白酶水解8 h后的水解物具有最强的促进乳酸菌生长作用.本试验进一步考察了该水解物对酸乳乳酸菌代谢产物(乳酸和胞外多糖)的产量及活菌数变化的影响.结果表明木瓜蛋白酶酪蛋白水解液能将乳酸菌乳酸和胞外多糖的产量分别提高33.1%和30.4%.%The influence of casein hydrolysate treated by papain on growth of lactic acid bacteria (Lactobacillus bulgaricus:Streptococcus thermophilus = 1:1) was studied. The hydrolysate treated by papain for 8 h displayed the highest growth-promoting activity for the strains. ln addition, the effect of casein hydrolysate on the bacterial viability, the yield of lactic acid and exopolysaccharide from lactic acid bacteria was determined. These results suggested that the yield of lactic acid and exopolysaccharide could be improved by 33.1% and 30.4%, respectively.

  8. Casein kinase II protein kinase is bound to lamina-matrix and phosphorylates lamin-like protein in isolated pea nuclei

    Science.gov (United States)

    Li, H.; Roux, S. J.

    1992-01-01

    A casein kinase II (CK II)-like protein kinase was identified and partially isolated from a purified envelope-matrix fraction of pea (Pisum sativum L.) nuclei. When [gamma-32P]ATP was directly added to the envelope-matrix preparation, the three most heavily labeled protein bands had molecular masses near 71, 48, and 46 kDa. Protein kinases were removed from the preparation by sequential extraction with Triton X-100, EGTA, 0.3 M NaCl, and a pH 10.5 buffer, but an active kinase still remained bound to the remaining lamina-matrix fraction after these treatments. This kinase had properties resembling CK II kinases previously characterized from animal and plant sources: it preferred casein as an artificial substrate, could use GTP as efficiently as ATP as the phosphoryl donor, was stimulated by spermine, was calcium independent, and had a catalytic subunit of 36 kDa. Some animal and plant CK II kinases have regulatory subunits near 29 kDa, and a lamina-matrix-bound protein of this molecular mass was recognized on immunoblot by anti-Drosophila CK II polyclonal antibodies. Also found associated with the envelope-matrix fraction of pea nuclei were p34cdc2-like and Ca(2+)-dependent protein kinases, but their properties could not account for the protein kinase activity bound to the lamina. The 71-kDa substrate of the CK II-like kinase was lamin A-like, both in its molecular mass and in its cross-reactivity with anti-intermediate filament antibodies. Lamin phosphorylation is considered a crucial early step in the entry of cells into mitosis, so lamina-bound CK II kinases may be important control points for cellular proliferation.

  9. Micellar casein concentrate production with a 3X, 3-stage, uniform transmembrane pressure ceramic membrane process at 50°C.

    Science.gov (United States)

    Hurt, E; Zulewska, J; Newbold, M; Barbano, D M

    2010-12-01

    The production of serum protein (SP) and micellar casein from skim milk can be accomplished using microfiltration (MF). Potential commercial applications exist for both SP and micellar casein. Our research objective was to determine the total SP removal and SP removal for each stage, and the composition of retentates and permeates, for a 3×, continuous bleed-and-feed, 3-stage, uniform transmembrane pressure (UTP) system with 0.1-μm ceramic membranes, when processing pasteurized skim milk at 50°C with 2 stages of water diafiltration. For each of 4 replicates, about 1,100 kg of skim milk was pasteurized (72°C, 16s) and processed at 3× through the UTP MF system. Retentate from stage 1 was cooled to Kjeldahl methods; sodium dodecyl sulfate-PAGE analysis was also performed on the retentates from each stage. Theoretically, a 3-stage, 3× MF process could remove 97% of the SP from skim milk, with a cumulative SP removal of 68 and 90% after the first and second stages, respectively. The cumulative SP removal using a 3-stage, 3× MF process with a UTP system with 0.01-μm ceramic membranes in this experiment was 64.8 ± 0.8, 87.8 ± 1.6, and 98.3 ± 2.3% for the first, second, and third stages, respectively, when calculated using the mass of SP removed in the permeate of each stage. Various methods of calculation of SP removal were evaluated. Given the analytical limitations in the various methods for measuring SP removal, calculation of SP removal based on the mass of SP in the skim milk (determined by Kjeldahl) and the mass SP present in all of the permeate produced by the process (determined by Kjeldahl) provided the best estimate of SP removal for an MF process.

  10. Study on PCR-RFLP of αS1-casein Gene and κ-casein Gene in Tianzhu White Yak%天祝白牦牛αs1-酪蛋白基因和κ-酪蛋白基因的PCR-RFLP研究

    Institute of Scientific and Technical Information of China (English)

    白文林; 郑玉才; 尹荣焕; 罗光彬; 朱建勇

    2005-01-01

    利用PCR-RFLP技术,检测了天祝白牦牛αS1-酪蛋白(αs1-casein,αs1-CN)基因和κ-酪蛋白(κ-casein,κ-CN)基因部分序列的遗传多态性,结果表明:天祝白牦牛群体αs1-CN基因表现单态,κ-CN基因存在遗传多态性.κ-CN基因PCR-RFLP位点等位基因A和B的基因频率分别为0.074 5和0.9255.κ-CN基因PCR-RFLP位点的基因型分布符合Hardy-Weinberg平衡定理(P>0.05).天祝白牦牛群体内平均基因一致度、基因多样度和有效等位基因数分别为0.9311、0.068 9和1.073 9.

  11. Expression of αs1-casein in benign prostatic hyperplasias%乳蛋白αs1-Casein在良性前列腺增生患者中的表达

    Institute of Scientific and Technical Information of China (English)

    赵国栋; 王驭良; 张晓鹏; 许克新; 王晓峰

    2009-01-01

    目的 检测良性前列腺增生(BPH)患者组织中蛋白表达的特点,了解有无与BPH相关的特异性蛋白表达.方法 通过双向电泳方法 所发现的检测BPH组织特异性蛋白表达,αs1-Casein进行定量免疫组化研究来验证该蛋白表达的特异性.结果 通过对正常前列腺组织,BPH及前列腺癌组织进行免疫组织化学染色,发现αs1-Casein在90%(20/22)的BPH组织中呈弱到强表达,而在正常前列腺组织中未见表达(0/10),在前列腺癌组织中的表达也不足10%(3/30).结论 αs1-Casein可能是一种BPH诊断的生物标记物.%Objective To analyze the characteristic of protein profile of benign prostatic hyperplasia (BPH) tissue and to further find the special proteins associated with BPH. Methods Protein profiles of human expressed prostatic secretion (EPS) samples obtained from BPH patients and normal males were comparatively analyzed by two-dimensional gel electrophoresis. In the resulting electrophoretograms, several differentially expressed proteins were identified. In this study, a distinct expressed protein αs1-casein was validated in BPH. Results Immunohistochemistry analysis showed that αs1-casein was mainly distributed in the epithelium of hyperplastic prostate. The level of the exression of αs1-casein in the tissue of BPH was found to be higher than that in prostatic carcinoma; whereas no asl-casein was detected in normal tissue.Western blotting analysis was also revealed same expression pattern of asl-casein was detected in BPH-EPS and BPH-free EPS. Conclusion asl-casein might be associated with BPH development and be used as a potential biological marker for the diagnosis of BPH.

  12. 巴氏杀菌与超高温灭菌牛乳酪蛋白结构差异性的研究%Research on the Structural Differences of the Casein from Milk by Pasteurization and Ultrahigh Temperature Sterilization

    Institute of Scientific and Technical Information of China (English)

    李子超; 徐明芳; 向明霞; 成希飞

    2013-01-01

    Secondary structure, intrinsic fluorescence emission spectra, micelle morphology and particle size distribution of bovine casein were researched respectively by circular dichroism, fluorescence spectro-photometer, scanning electron microscope and nano-particle size analyzer. Results showed that bovine casein by ultrahigh temperature sterilization (UHT) had more random structures (α-helix 22. 1% , β-sheet 23. 1% , β-turn 22. 4% , random 33. 4% ) , compared with casein by pasteurization( α-helix 47. 4% , β-sheet 19. 7% , β-turn 13. 4% , random 19. 4% ). Tryptophan of casein by UHT had more hydrophobic. Casein particles by pasteurization were spherical with smooth surface, and able to connect to short micelles. But casein particle by UHT did not have smooth surface, and could not connect to micelles. Compared with pasteurization, casein particles by UHT was smaller, with the diameter being 221. 7 nm. This research suggested the structure of casein by pasteurization and ultrahigh temperature sterilization had obvious differences.%采用圆二色谱(CD)、荧光分光光度计、扫描电子显微镜(SEM)、纳米粒度仪对巴氏杀菌与超高温灭菌(UHT)牛乳酪蛋白的二级结构、内源荧光发射光谱、胶束形态结构、粒径分布情况进行研究.结果表明,相对于巴氏杀菌牛乳酪蛋白(α-螺旋47.4%、β-折叠19.7%、β-转角13.4%、无规卷曲19.4%),UHT牛乳酪蛋白的无规则结构增多(α-螺旋22.1%、β-折叠23.1%、β-转角22.4%、无规卷曲33.4%);UHT牛乳酪蛋白色氨酸在酪蛋白中所处的环境疏水性增强;巴氏杀菌牛乳酪蛋白颗粒呈圆球状,表面光滑,能够连接成较短的胶束结构,而UHT牛乳酪蛋白表面不光滑,几乎不能形成胶束;巴氏杀菌牛乳酪蛋白平均粒径为295.1 nm,UHT乳酪蛋白平均颗粒明显变小,平均粒径为221.7 nm.可见,巴氏杀菌乳与超高温灭菌乳之间存在明显的结构差异.

  13. Relationship between somatic cell counts in raw milk and the casein fractions of UHT milk%原料乳中体细胞数与UHT乳中酪蛋白成分的关系研究

    Institute of Scientific and Technical Information of China (English)

    沙淼; 肖洪亮

    2011-01-01

    The relationship between SCC in raw milk and casein fractions of 15 batches of UHT milk was studied. The raw milk was collected, pasteurized and transferred to UHT process. Samples of UHT milk were collected on days 8, 30, 60, 90 and 120 of storage at room temperature. Their casein fractions were analyzed by high performance liquid chromatography. The SCC ranged from 1.97 × 105 to 8 × 105 mL-1.No correlation (P<0.05) was found between SCC and κ-casein concentrations in raw or UHT milks. The αs2- and β-casein concentrations in raw milk were negatively correlated with SCC(P<0.05). In UHT milk, negative correlations were observed for αs1-casein (P<0.05) and β-casein(P<0.05) on the 8th day, and for α52-casein (P<0.01) on the 60th day of storage. The results showed that higher SCC in raw milk is associated with substantial degradation ofβ-casem and αs-casein, which may lead to quality defects in UHT milk during storage.%研究了原料乳中体细胞数与15批次UHT乳样本中酪蛋白成分之间的关系.将原料乳巴氏杀菌后进行超高温处理.分别于8,30,60,90和120 d采集贮藏于室温条件下的UHT乳样本,并使用高效液相色谱法对酪蛋白成分进行分析.体细胞数范围1.97×105~8×105 mL-1.体细胞数与原料乳或UHT乳中的κ-酪蛋白质量浓度之间没有相关性(P<0.05).原料乳中α-酪蛋白和β-酪蛋白与体细胞数呈负相关(P<0.05).UHT乳中,αs1-酪蛋白(P<0.05)和β-酪蛋白(P<0.05)与体细胞数在贮藏第8天呈负相关,αs2-(P<0.01)与体细胞数在贮藏第60天呈负相关.结果表明,原料乳中体细胞数较高与β-酪蛋白和αs-酪蛋白的大量水解有关,并且可能导致UHT乳在贮藏期内出现质量问题.

  14. THE EFFECTS OF PRE-AND POST-EXERCISE WHEY VS. CASEIN PROTEIN CONSUMPTION ON BODY COMPOSITION AND PERFORMANCE MEASURES IN COLLEGIATE FEMALE ATHLETES

    Directory of Open Access Journals (Sweden)

    olin D. Wilborn

    2013-03-01

    Full Text Available Two of the most popular forms of protein on the market are whey and casein. Both proteins are derived from milk but each protein differs in absorption rate and bioavailability, thus it is possible that each type of protein may contribute differently to the adaptations elicited through resistance training. Therefore, the purpose of this study was to investigate the potential effects of ingestion of two types of protein in conjunction with a controlled resistance training program in collegiate female basketball players. Sixteen NCAA Division III female basketball players were matched according to body mass and randomly assigned in a double-blind manner to consume 24 g whey protein (WP (N = 8, 20.0 ± 1.9 years, 1.58 ± 0.27 m, 66. 0 ± 4.9 kg, 27.0 ± 4.9 %BF or 24 g casein protein (CP (N = 8, 21.0 ± 2.8 years, 1.53 ± 0.29 m, 68.0 ± 2.9 kg, 25.0 ± 5.7 %BF immediately pre- and post-exercise for eight weeks. Subjects participated in a supervised 4-day per week undulating periodized training program. At 0 and 8 weeks, subjects underwent DXA body composition analysis, and at 0 and 8 weeks underwent one repetition maximum (1RM strength, muscle endurance, vertical jump, 5-10-5 agility run, and broad jump testing sessions. Data were analyzed using repeated measures ANOVA, and presented as mean ± SD changes from baseline after 60 days. No significant group x time interaction effects were observed among groups in changes in any variable (p > 0.05. A significant time effect was observed for body fat (WP: -2.0 ± 1.1 %BF; CP: -1.0 ± 1.6 %BF, p < 0.001, lean mass (WP: 1.5 ± 1.0 kg; CP: 1. 4 ± 1.0 kg, p < 0.001, fat mass (WP: -1.3 ± 1.2 kg; CP: -0.6 ± 1.4 kg, p < 0.001, leg press 1RM (WP: 88.7 ± 43.9 kg; CP: 90.0 ± 48.5 kg, p < 0.001, bench press 1RM (WP: 7.5 ± 4.6 kg; CP: 4.3 ± 4.5 kg, p = 0.01, vertical jump (WP: 4.1 ± 1.8 cm; CP: 3.5 ± 7.6 cm, p < 0.001, 5-10-5 (WP: -0.3 ± 0.2 sec; CP: -0.09 ± 0.42 sec, p < 0.001, and broad jump (WP: 10

  15. Newly identified mutations at the CSN1S1 gene in Ethiopian goats affect casein content and coagulation properties of their milk.

    Science.gov (United States)

    Mestawet, T A; Girma, A; Adnøy, T; Devold, T G; Vegarud, G E

    2013-08-01

    Very high casein content and good coagulation properties previously observed in some Ethiopian goat breeds led to investigating the αs1-casein (CSN1S1) gene in these breeds. Selected regions of the CSN1S1 gene were sequenced in 115 goats from 5 breeds (2 indigenous: Arsi-Bale and Somali, 1 exotic: Boer, and 2 crossbreeds: Boer × Arsi-Bale and Boer × Somali). The DNA analysis resulted in 35 new mutations: 3 in exons, 3 in the 5' untranslated region (UTR), and 29 in the introns. The mutations in exons that resulted in an amino acid shift were then picked to evaluate their influence on individual casein content (αs1-, αs2-, β-, and κ-CN), micellar size, and coagulation properties in the milk from the 5 goat breeds. A mutation at nucleotide 10657 (exon 10) involved a transversion: CAG→CCG, resulting in an amino acid exchange Gln77→Pro77. This mutation was associated with the indigenous breeds only. Two new mutations, at nucleotide 6072 (exon 4) and 12165 (exon 12), revealed synonymous transitions: GTC→GTT in Val15 and AGA→AGG in Arg100 of the mature protein. Transitions G→A and C→T at nucleotides 1374 and 1866, respectively, occurred in the 5' UTR, whereas the third mutation involved a transversion T→G at nucleotide location 1592. The goats were grouped into homozygote new (CC), homozygote reference (AA), and heterozygote (CA) based on the nucleotide that involved the transversion. The content of αs1-CN (15.32g/kg) in milk samples of goats homozygous (CC) for this newly identified mutation, Gln77→Pro77 was significantly higher than in milks of heterozygous (CA; 9.05g/kg) and reference (AA; 7.61g/kg) genotype animals. The αs2-, β-, and κ-CN contents showed a similar pattern. Milk from goats with a homozygous new mutation had significantly lower micellar size. Milk from both homozygote and heterozygote new-mutation goats had significantly shorter coagulation rate and stronger gel than the reference genotype. Except the transversion, the

  16. 葡萄糖对脱脂乳酪蛋白胶束稳定性的影响研究%Study on the influence of glucose on the stability of casein micelles in skim milk

    Institute of Scientific and Technical Information of China (English)

    杨敏; 梁琪; 乔海军; 张卫兵; 孙雪燕; 甘伯中

    2012-01-01

    摘要:研究了葡萄糖添加量、体系pH、热处理温度、热处理时间对脱脂牛乳酪蛋白胶束稳定性的影响。研究表明,在接近中性pH条件下,少量葡萄糖分子可降低脱脂乳酪蛋白胶束的稳定性,大量葡萄糖分子可增强其稳定性。添加葡萄糖后,在高温热处理的诱导下,酪蛋白沉淀的pH升高。随着热处理时间的延长,脱脂乳中酪蛋白胶束表现出聚集行为.致使粒径增大.浊度和沉淀率总体呈现上升趋势。该研究结论可为乳品加工提供参考依据。%The influence of the glucose amount,the system pH,the heat treatment temperature,the heat treatment time on the stability of casein micelles of skim milk were studied. The result showed that,nearly neutral pH,the stability of skim milk casein micelles was reduced with a small amount of glucose,which was increased with a large number of glucose. The pH of the casein precipitation was increased by adding glucose on the high temperature heat treatment. With the extension of the heat treatment time,casein micelles showed aggregation behavior,the particle size was increased,which induced the turbidity and sedimentation amount upward. The conclusion would provide a reference for the dairy processing.

  17. 多酚氧化酶交联β-酪蛋白的抗原性变化初步研究%Antigenicity changes of enzymatically crosslinked β-casein by polyphenol oxidase

    Institute of Scientific and Technical Information of China (English)

    程伟; 高金燕; 李欣; 刘法辉; 陈红兵

    2012-01-01

    The study focused on the antigenicity changes of cross-linked β-casein catalyzed by polyphenol oxidase using indirect competitive ELISA method. The SDS-PAGE profile showed that the polyphenol oxidase could catalyze the cross-linked β-casein effectively. Meanwhile, according to the results of indirect competitive ELISA,the half inhibitory concentration (IC50 values)of β-casein after crosslinked changed from 2.63μg/mL into 4.07μg/mL,indicating the antigenicity of crosslinked β-casein decreased significantly. It might provide some theoretical basis for developing hypoallergenic dairy through protein crosslinking by polyphenol oxidase.%利用多酚氧化酶催化牛乳β-酪蛋白交联,并通过ELISA方法检测交联前后β-酪蛋白抗原性的变化。SDS-PAGE结果显示,多酚氧化酶可以有效地催化β-酪蛋白交联。同时,间接竞争ELISA检测的β-酪蛋白交联后的半抑制浓度(IC50值)由2.63μg/mL变为4.07μg/mL,表明交联后β-酪蛋白抗原性明显降低。本研究工作为通过多酚氧化酶交联制备低致敏性乳制品提供了部分理论依据。

  18. 胰蛋白酶水解酪蛋白制备活性多肽的指数形式动力学新模型%A Novel Exponential Kinetic Model for Casein Tryptic Hydrolysis to Prepare Active Peptides

    Institute of Scientific and Technical Information of China (English)

    何志敏; 齐崴; 何明霞

    2002-01-01

    The kinetics of casein tryptic hydrolysis to prepare active peptides was investigated. Taking intoaccount the reaction mechanism including single substrate hydrolysis, irreversible enzyme inactivation, and substrateinhibition, a set of exponential equations was established to characterize the enzymatic hydrolysis curves. Theverification was carried out by a series of experimental results and indicated that the average regressive error wasless than 5%. According to the proposed kinetic model, the kinetic constants and thermodynamic constants of thereaction system were also calculated.

  19. Structural variability of the neutral carbohydrate moiety of cow colostrum kappa-casein as a function of time after parturition. Identification of a tetrasaccharide with blood group I specificity

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Fiat, A.-M.; Chevan, J.; Jollès, P.; Waard, P. de; Piller, F.; Cartron, J.-P.

    1988-01-01

    New neutral oligosaccharides from cow colostrum -casein were identified and characterized by 500-MHz 1H-NMR spectroscopy. Their structures are Galbeta(1->3)GalNAc-ol, Galbeta(1->3)[GlcNAcbeta(1->6)]GalNAc-ol, Galbeta(1->3)[Galbeta(1->4)GlcNAc(beta1->6)]GalNAc-ol, Galbeta(1->3){Fucalpha(1->3)[Galbeta

  20. Dietary inositol hexakisphosphate, but not myo-inositol, clearly improves hypercholesterolemia in rats fed casein-type amino acid mixtures and 1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane.

    Science.gov (United States)

    Okazaki, Yukako; Katayama, Tetsuyuki

    2008-10-01

    We have previously shown that dietary inositol hexakisphosphate (IP6) and myo-inositol prevent fatty liver in rats fed a casein-based diet containing 1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane (DDT). This study was performed to examine the comparative effects of dietary equimolar amounts of sodium IP6 (1.02%) and myo-inositol (0.2%) on the development of DDT-induced fatty liver and hypercholesterolemia in rats fed 20% casein-type amino acid mixtures designed to exclude a possible myo-inositol contaminant in casein. Thirty-six male Wistar rats were divided into 6 groups of 6 rats each for: a control group, myo-inositol-supplemented group, IP6-supplemented group, DDT-treated group, DDT + myo-inositol-supplemented group, and a DDT + IP6-supplemented group. Dietary IP6 clearly suppressed the rises in serum concentrations of cholesterol and phospholipids because of DDT feeding, but myo-inositol had no significant influence on such elevations. Dietary IP6, but not myo-inositol, caused significant body weight gain with or without DDT intake. Supplemental IP6 and myo-inositol significantly increased hepatic-free myo-inositol regardless of DDT intake and prevented fatty liver in rats fed DDT. In conclusion, dietary IP6 and myo-inositol exert similar effects on DDT-induced fatty liver and myo-inositol status but distinct effects on DDT-induced hypercholesterolemia and growth rate in rats fed casein-type amino acid mixtures.

  1. Un anxiolytique naturel: l'hydrolysat trypsique de caseine alpha-s1 de lait bovin. Son intérêt en médecine humaine et vétérinaire

    OpenAIRE

    2009-01-01

    Resume Produit d?origine naturelle, l?hydrolysat trypsique de caseine alpha-s1 de lait bovin (HTC) contient un decapeptide actif, l?alpha-casozepine, aux proprietes pharmacologiques interessantes. Les tests et les essais precliniques et cliniques, realises tant sur des animaux (rats, chiens, chats) que sur des humains, ont en effet mis en evidence pour cette molecule : une affinite certaine pour les recepteurs GABA-A avec profil benzodiazepine-like, une action anxiolytique et anti-...

  2. PENGEMBANGAN TORTILA BERKALSIUM SEBAGAI ALTERNATIF PANGAN DIET CASEIN FREE-GLUTEN FREE PADA INDUSTRI KECIL DENGAN METODE VALUE ENGINEERING (Development of Fortified Calcium Tortilla Snack as an Alternative Food for Casein-Free Gluten-Free Diet with Value Engineering Method for Small Scale Industry

    Directory of Open Access Journals (Sweden)

    Jeremy Yonathan Sadikin

    2015-09-01

    Full Text Available The number of people with autism increased 56% in 1998 – 2013, and it was a global problem. People with autism need special treatments and CFGF diet (casein free, gluten free was one of those treatments. That’s why, the development The calcium content was expected to substitute the calcium from dairy consumption, which shouldn’t be consumed by people with autism. The method used in this product development was value engineering which separated in three steps: information, creativity, and analysis steps. Respectively, this research was also further completed with chemical The goal of this research was to design some product implemented in small scale industry. Respondends and panelist in this research were consisted of students and teachers. They acted as the market of the product, especially as a  part of general society. This product were designed to provide CFGF snack for people with autism, and those who need CFGF diet. But this product was not limited to that market, it can be consumed by general society not only for people with autism, hence the students and teachers were used. The research showed that the best concept was a product produced with to get 200 grams of dough. This product concept was also designed to be packed in big size gusset packaging materials and the chips was triangle-shaped with size of feasible to be produced in small scale industry. Keywords: value engineering, casein-free gluten-free diet,autism   ABSTRAK Dengan jumlah penyandang autis yang terus meningkat, misalnya peningkatan sebesar 56% pada 1998 – 2013, maka produk tortila berkalsium potensial dikembangkan sebagai alternatif pangan untuk diet CFGF (, dan kandungan kalsiumnya bisa membantu menggantikan kalsium dari susu sapi yang mengandung kasein. Tujuan penelitian adalah merancang sejumlah konsep produk tortila berkalsium dan memilih satu konsep yang paling disukai Metode penelitian adalah yang terdiri dari tiga tahap: informasi, kreativitas dan

  3. In vitro digestion of purified β-casein variants A(1), A(2), B, and I: effects on antioxidant and angiotensin-converting enzyme inhibitory capacity.

    Science.gov (United States)

    Petrat-Melin, B; Andersen, P; Rasmussen, J T; Poulsen, N A; Larsen, L B; Young, J F

    2015-01-01

    Genetic polymorphisms of bovine milk proteins affect the protein profile of the milk and, hence, certain technological properties, such as casein (CN) number and cheese yield. However, reports show that such polymorphisms may also affect the health-related properties of milk. Therefore, to gain insight into their digestion pattern and bioactive potential, β-CN was purified from bovine milk originating from cows homozygous for the variants A(1), A(2), B, and I by a combination of cold storage, ultracentrifugation, and acid precipitation. The purity of the isolated β-CN was determined by HPLC, variants were verified by mass spectrometry, and molar extinction coefficients at λ=280nm were determined. β-Casein from each of the variants was subjected to in vitro digestion using pepsin and pancreatic enzymes. Antioxidant and angiotensin-converting enzyme (ACE) inhibitory capacities of the hydrolysates were assessed at 3 stages of digestion and related to that of the undigested samples. Neither molar extinction coefficients nor overall digestibility varied significantly between these 4 variants; however, clear differences in digestion pattern were indicated by gel electrophoresis. In particular, after 60min of pepsin followed by 5min of pancreatic enzyme digestion, one ≈4kDa peptide with the N-terminal sequence (106)H-K-E-M-P-F-P-K- was absent from β-CN variant B. This is likely a result of the (122)Ser to (122)Arg substitution in variant B introducing a novel trypsin cleavage site, leading to the changed digestion pattern. All investigated β-CN variants exhibited a significant increase in antioxidant capacity upon digestion, as measured by the Trolox-equivalent antioxidant capacity assay. After 60min of pepsin + 120min of pancreatic enzyme digestion, the accumulated increase in antioxidant capacity was ≈1.7-fold for the 4 β-CN variants. The ACE inhibitory capacity was also significantly increased by digestion, with the B variant reaching the highest inhibitory

  4. Bioefficacy of tea catechins encapsulated in casein micelles tested on a normal mouse cell line (4D/WT) and its cancerous counterpart (D/v-src) before and after in vitro digestion.

    Science.gov (United States)

    Haratifar, Sanaz; Meckling, Kelly A; Corredig, Milena

    2014-06-01

    Numerous studies have demonstrated that tea catechins form complexes with milk proteins, especially caseins. Much less work has been conducted to understand the metabolic conversions of tea-milk complexes during gastro-duodenal digestion. The objective of this study was to determine the significance of this association on the digestibility of the milk proteins and on the bioaccessibility of the tea polyphenol epigallocatechin gallate (EGCG). An in vitro digestion model mimicking the gastric and duodenal phases of the human gastrointestinal tract was employed to follow the fate of the milk proteins during digestion and determine the bioefficacy of EGCG isolated or encapsulated with the caseins. The samples, before and after digestion, were tested using two parallel colonic epithelial cell lines, a normal line (4D/WT) and its cancerous transformed counterpart (D/v-src). EGCG caused a decrease in proliferation of cancer cells, while in normal cells, neither isolated nor encapsulated EGCG affected cell proliferation, at concentrations <0.15 mg ml(-1). At higher concentrations, both isolated and encapsulated produced similar decreases in proliferation. On the other hand, the bioefficacy on the cancer cell line showed some differences at lower concentrations. The results demonstrated that regardless of the extent of digestion of the nanoencapsulated EGCG, the bioefficacy of EGCG was not diminished, confirming that casein micelles are an appropriate delivery system for polyphenols.

  5. Obtenção e caracterização química e nutricional de diferentes concentrados de caseína Obtention and chemical and nutritional characterization of different bovine casein concentrates

    Directory of Open Access Journals (Sweden)

    Janesca Alban Roman

    2005-02-01

    aos demais concentrados, quanto aos índices quociente de eficiência líquida da proteína e quociente de eficiência protéica operacional.OBJETIVE: The objective of the present work was to evaluate the centesimal composition, the amino acid profile and the the composition and nutritive value of three casein concentrates, obtained by different methods. METHODS: The casein concentrates were analysed according to the following methods: a commercial casein obtained by acid precipitation (pI followed by neutralization; an enzyme coagulated casein obtained by rennet coagulation; and a casein micelles concentrate obtained by microlfiltration and diafiltration. The Centesimal composition was determined by the procedures described in the manual Official Methods of Analysis. The amino acid profiles were determined after the protein acid hydrolysis (HCl 6N, 105°C, 22h in an amino acid autoanalyzer by cation exchange chromatography and post-column ninhydrin reaction. The essential amino acids were in accordance with Food and Agriculture Organization/World Health Organization recommendation for children 2 to 5 years of age. The nutritive value was determined on 21-day old rats of the Wistar strain through apparent net protein ratio, and protein efficiency ratio operational. RESULTS: Commercial casein presented higher protein concentration (92.0% than micellar casein (86.0% and casein clot (72.0%. The animals in the various protein diets did not show significant differences as to body weight gain and diet consumption. The highest digestibility was that of commercial casein (93.8%, compared to the other two concentrates (91.0%. CONCLUSION: The casein concentrates showed differences related to the centesimal composition, since the commercial casein presented a higher protein concentration. The casein clot was inferior to the other protein concentrates regarding net protein ratio and protein efficiency ratio operational.

  6. Optimal conditions to glycosylate and cross-link casein by transglutaminase and some functional properties of the modified product%酪蛋白的转谷氨酰胺酶酶促糖基化交联条件及产物性质

    Institute of Scientific and Technical Information of China (English)

    姜淑娟; 冯镇; 赵新淮

    2011-01-01

    Glycosylation and cross-linking of casein catalyzed by transglutaminase in presence of glucosamine was studied in this work. When the concentration of casein was fixed at 3% (w/v) and glucosamine added to the final concentration of 3 mol glucosamine /kg casein, the content of glucosamine conjugated in the modified casein product was used as an index, the pH of reaction system, addition level of transglutaminase, reaction temperature and time were studied by single factor experiments. The optimal modification conditions final selected were as fellow: a pH of 7.5, enzyme addition level of 10 kU/kg casein, temperature of 37 ℃ and reaction time of 4 h. Compared to the original casein and the cross-linked casein by transglutaminase, the modified casein product exhibited markedly improved emulsifying and gelation properties; moreover, its digestibility in vitro wasn't impaired upon this modification. Our results indicated that glycosylation and cross-linking of casein catalyzed by transglutaminase could improve these important properties of casein.%在氨基葡萄糖存在的条件下,利用转谷氨酰胺酶(EC 2.3.2.13)对酪蛋白进行糖基化交联修饰.以修饰酪蛋白产物中氨基葡萄糖的导入量为指标,采用单因素试验分别考察反应体系pH值、酶添加量、反应温度和时间对修饰反应的影响.优化后的适宜修饰条件为:酪蛋白底物质量浓度为30 g/L,氨基葡萄糖添加量为3 mol(每kg酪蛋白中)、pH值为7.5、酶添加量为10 kU(每kg酪蛋白中)、反应温度为37 C、时间4h.与酪蛋白和转谷氨酰胺酶促交联的酪蛋白相比,修饰酪蛋白产物的乳化性质和胶凝性质得到显著改善,并且体外消化性能未受到影响,表明转谷氨酰胺酶催化的糖基化交联修饰可以用于改善酪蛋白的这些功能性质.

  7. Short communication: Simultaneous identification of five kappa-casein (CSN3) alleles in domestic goat by polymerase chain reaction-single strand conformation polymorphism.

    Science.gov (United States)

    Chessa, S; Budelli, E; Gutscher, K; Caroli, A; Erhardt, G

    2003-11-01

    Until now, a total of nine polymorphic sites corresponding to six different alleles have been described at the kappa-casein (CSN3) locus in the domestic goat (Capra hircus). A protocol for the rapid and simultaneous genotyping of five goat CSN3 alleles by using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique was developed. Moreover, the developed test was validated by screening the CSN3 variability in four Italian breeds, Garganica, Jonica, Maltese, and Camosciata. Seven different patterns were readily identifiable. These corresponded to five known alleles and two newly identified variants. The G/A substitution at nucleotide position 471, which is not identifiable at the protein level but was found to be very frequent in the typed breeds, is easily detectable by the protocol developed. The PCR-SSCP analysis is a powerful tool for the genetic study of CSN3 variability in domestic goats, allowing both the simultaneous identification of different alleles, and the detection of new variants.

  8. Effects of the addition of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on mechanical properties of luting and lining glass ionomer cement

    Science.gov (United States)

    Heravi, Farzin; Bagheri, Hossein; Rangrazi, Abdolrasoul; Mojtaba Zebarjad, Seyed

    2016-07-01

    Recently, the addition of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) into glass ionomer cements (GICs) has attracted interest due to its remineralization of teeth and its antibacterial effects. However, it should be investigated to ensure that the incorporation of CPP-ACP does not have significant adverse effects on its mechanical properties. The purpose of this study was to evaluate the effects of the addition of CPP-ACP on the mechanical properties of luting and lining GIC. The first step was to synthesize the CPP-ACP. Then the CPP-ACP at concentrations of 1%, 1.56% and 2% of CPP-ACP was added into a luting and lining GIC. GIC without CPP-ACP was used as a control group. The results revealed that the incorporation of CPP-ACP up to 1.56%(w/w) increased the flexural strength (29%), diametral tensile strength (36%) and microhardness (18%), followed by a reduction in these mechanical properties at 2%(w/w) CPP-ACP. The wear rate was significantly decreased (23%) in 1.56%(w/w) concentration of CPP-ACP and it was increased in 2%(w/w). Accordingly, the addition of 1.56%(w/w) CPP-ACP into luting and lining GIC had no adverse effect on the mechanical properties of luting and lining GIC and could be used in clinical practice.

  9. Immunohistochemical and Proteomic Evaluation of Nuclear Ubiquitous Casein and Cyclin-Dependent Kinases Substrate in Invasive Ductal Carcinoma of the Breast

    Directory of Open Access Journals (Sweden)

    Piotr Ziółkowski

    2009-01-01

    Full Text Available Nuclear ubiquitous casein and cyclin-dependent kinases substrate (NUCKS is 27 kDa chromosomal protein of unknown function. Its amino acid composition as well as structure of its DNA binding domain resembles that of high-mobility group A, HMGA proteins. HMGA proteins are associated with various malignancies. Since changes in expression of HMGA are considered as marker of tumor progression, it is possible that similar changes in expression of NUCKS could be useful tool in diagnosis and prognosis of breast cancer. For identification and analysis of NUCKS we used proteomic and histochemical methods. Analysis of patient-matched samples of normal and breast cancer by mass spectrometry revealed elevated levels of NUCKS in protein extracts from ductal breast cancers. We elicited specific antibodies against NUCKS and used them for immunohistochemistry in invasive ductal carcinoma of breast. We found high expression of NUCKS in 84.3% of cancer cells. We suggest that such overexpression of NUCKS can play significant role in breast cancer biology.

  10. Resistant starch modification: effects on starch properties and functionality as co-encapsulant in sodium caseinate-based fish oil microcapsules.

    Science.gov (United States)

    Chung, C; Sanguansri, L; Augustin, M A

    2010-01-01

    The properties of resistant starch (RS) modified by heating starch suspensions (Heat RS) or heating followed by microfluidization (Heat-MF RS) and their functionality as co-encapsulants in sodium caseinate (NaCas) based fish oil microcapsules (50%oil:25%NaCas:25%starch) were examined. RS modification reduced molecular weight and crystallinity of the starch, with the effects being more evident for Heat-MF RS. The properties of fish oil microcapsules were influenced by the starch type used (RS, Heat RS, or Heat-MF RS) in combination with NaCas. With both physical blends and heated mixtures of NaCas and starch as encapsulants, highest encapsulation efficiency but lowest oxidative stability was obtained for the microcapsules containing Heat-MF RS. Oxidative stability was independent of heat treatment applied to the mixtures of NaCas and starch and also not related to encapsulation efficiency of the freeze-dried microcapsules. The properties of the starch used in combination with NaCas were the major determinant of the oxidative stability, with lower molecular weight and decreased crystallinity providing less protection against oxidation.

  11. High expression of human se-rum albumin in milk of trans-genic mice directed by the goat b-casein gene promoter region

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    We have constructed a mammary gland expression vector that contained the goat b-casein gene promoter, 5′upstream regulatory region, exons 1, 2, intron 1 as well as the human serum albumin (hALB) mini-gene (including the full-long sequences of hALB cDNA and its intron 1). Injec-tion of the vector into mouse tail veins showed that the re-combinant construct was expressed only in mammary glands. The vector was microinjected into the mouse fertilized eggs, followed by transferring the eggs into the foster mice. 33 F0 mice were obtained. Of the 33, 8 mice (5♀, 3♂) were trans-genic with hALB gene integration identified by PCR as well as Southern blot hybridization. The integration rate was 24.2% (8/33). Western blot analysis showed that 3 female transgenic mice had hALB expression in their milk. The hALB contents in milk reached 3.54, 0.21 and 3.03 g/L, re-spectively.

  12. Pharmacological and safety evaluation of CIGB-300, a casein kinase 2 inhibitor peptide, administered intralesionally to patients with cervical cancer stage IB2/II

    Directory of Open Access Journals (Sweden)

    Soriano-García JL

    2013-08-01

    Full Text Available CIGB-300 is a pro-apoptotic casein kinase 2 inhibitor peptide with potential anticancer action. An open-label and dose scaling Phase I trial was carried out to investigate the peptide tumor uptake, pharmacokinetics, toxicity, and levels of a CIGB-300 response biomarker in patients with cervical cancer stage IB2/II. Fourteen patients were included; six of them received 35 mg, 6 received 70 mg and the two remaining patients received 245 mg of CIGB-300 prior chemoradiotherapy. CIGB-300 was applied by intratumor injections during 5-consecutive days. For pharmacokinetic and biodistribution studies, the peptide was radiolabeled with 99mTc in the first administration and whole body gammagraphy and plasma testing were done during 48 h. Data showed that the maximum tolerated dose was 70 mg for CIGB-300 in this clinical setting. Furthermore, an allergic-like syndrome was identified as the dose limiting toxicity, which was well-correlated with plasmatic histamine levels. Importantly, the mean tumor uptake was 14.9 mg and 10.4 mg for CIGB-300 doses of 35 and 70 mg, respectively. Also, the kidneys were the main target organ for drug elimination. Finally, treatment with CIGB-300 significantly reduced the B23/nucleophosmin levels in tumor specimens. CIGB-300 meets potentialities to be tested in future trials in a neoadjuvant setting prior to chemoradiotherapy in cervical cancer.

  13. Casein phosphopeptides and CaCl2 increase penicillin production and cause an increment in microbody/peroxisome proteins in Penicillium chrysogenum.

    Science.gov (United States)

    Domínguez-Santos, Rebeca; Kosalková, Katarina; García-Estrada, Carlos; Barreiro, Carlos; Ibáñez, Ana; Morales, Alejandro; Martín, Juan-Francisco

    2017-03-06

    Transport of penicillin intermediates and penicillin secretion are still poorly characterized in Penicillium chrysogenum (re-identified as Penicillium rubens). Calcium (Ca(2+)) plays an important role in the metabolism of filamentous fungi, and casein phosphopeptides (CPP) are involved in Ca(2+) internalization. In this study we observe that the effect of CaCl2 and CPP is additive and promotes an increase in penicillin production of up to 10-12 fold. Combination of CaCl2 and CPP greatly promotes expression of the three penicillin biosynthetic genes. Comparative proteomic analysis by 2D-DIGE, identified 39 proteins differentially represented in P. chrysogenum Wisconsin 54-1255 after CPP/CaCl2 addition. The most interesting group of overrepresented proteins were a peroxisomal catalase, three proteins of the methylcitrate cycle, two aminotransferases and cystationine β-synthase, which are directly or indirectly related to the formation of penicillin amino acid precursors. Importantly, two of the enzymes of the penicillin pathway (isopenicillin N synthase and isopenicillin N acyltransferase) are clearly induced after CPP/CaCl2 addition. Most of these overrepresented proteins are either authentic peroxisomal proteins or microbody-associated proteins. This evidence suggests that addition of CPP/CaCl2 promotes the formation of penicillin precursors and the penicillin biosynthetic enzymes in peroxisomes and vesicles, which may be involved in transport and secretion of penicillin.

  14. Oxidative stability of a heme iron-fortified bakery product: Effectiveness of ascorbyl palmitate and co-spray-drying of heme iron with calcium caseinate.

    Science.gov (United States)

    Alemán, Mercedes; Bou, Ricard; Tres, Alba; Polo, Javier; Codony, Rafael; Guardiola, Francesc

    2016-04-01

    Fortification of food products with iron is a common strategy to prevent or overcome iron deficiency. However, any form of iron is a pro-oxidant and its addition will cause off-flavours and reduce a product's shelf life. A highly bioavailable heme iron ingredient was selected to fortify a chocolate cream used to fill sandwich-type cookies. Two different strategies were assessed for avoiding the heme iron catalytic effect on lipid oxidation: ascorbyl palmitate addition and co-spray-drying of heme iron with calcium caseinate. Oxidation development and sensory acceptability were monitored in the cookies over one-year of storage at room temperature in the dark. The addition of ascorbyl palmitate provided protection against oxidation and loss of tocopherols and tocotrienols during the preparation of cookies. In general, ascorbyl palmitate, either alone or in combination with the co-spray-dried heme iron, prevented primary oxidation and hexanal formation during storage. The combination of both strategies resulted in cookies that were acceptable from a sensory point of view after 1year of storage.

  15. Effect of the application of a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste and adhesive systems on bond durability of a fissure sealant.

    Science.gov (United States)

    Borges, Boniek Castillo Dutra; Catelan, Anderson; Sasaki, Robson Tetsuo; Ambrosano, Gláucia Maria Bovi; Reis, André Figueiredo; Aguiar, Flávio Henrique Baggio

    2013-01-01

    This study aimed to evaluate the effect of the previous application of a casein phosphopeptide-amorphous calcium phosphate paste (MI Paste, MI) and adhesive systems on the bond durability of a fissure sealant. Ninety-eight enamel blocks were obtained from proximal surfaces of erupted third molars. Specimens were divided into 14 groups (n = 7) according to the previous application of MI (with and without) and the adhesive systems used (no adhesive system; hydrophobic resin of a three-step etch-and-rinse adhesive system; etch-and-rinse single-bottle adhesive system; all-in-one adhesive system; two-step self-etching adhesive system; additional phosphoric acid conditioning and all-in-one adhesive system; additional phosphoric acid conditioning and two-step self-etching adhesive system). A fissure sealant (Fluroshield) was applied and photoactivated for 20 s. Beams (~0.7 mm(2)) were prepared for the microtensile bond strength test, which was executed after 24 h or 6 months of water storage. Fractured specimens were analyzed by scanning electronic microscopy. Data were analyzed by two-way ANOVA with repeated measures/Tukey's test (P adhesive systems presented higher means than those groups where MI was not applied. Higher frequency of cohesive failures was observed for groups with MI. Applying a CPP-ACP containing paste on enamel before adhesive systems was an effective method to increase bond durability of the sealant tested.

  16. Casein kinase II is required for proper cell division and acts as a negative regulator of centrosome duplication in Caenorhabditis elegans embryos

    Science.gov (United States)

    Medley, Jeffrey C.; Kabara, Megan M.; Stubenvoll, Michael D.; DeMeyer, Lauren E.

    2017-01-01

    ABSTRACT Centrosomes are the primary microtubule-organizing centers that orchestrate microtubule dynamics during the cell cycle. The correct number of centrosomes is pivotal for establishing bipolar mitotic spindles that ensure accurate segregation of chromosomes. Thus, centrioles must duplicate once per cell cycle, one daughter per mother centriole, the process of which requires highly coordinated actions among core factors and modulators. Protein phosphorylation is shown to regulate the stability, localization and activity of centrosome proteins. Here, we report the function of Casein kinase II (CK2) in early Caenorhabditis elegans embryos. The catalytic subunit (KIN-3/CK2α) of CK2 localizes to nuclei, centrosomes and midbodies. Inactivating CK2 leads to cell division defects, including chromosome missegregation, cytokinesis failure and aberrant centrosome behavior. Furthermore, depletion or inhibiting kinase activity of CK2 results in elevated ZYG-1 levels at centrosomes, restoring centrosome duplication and embryonic viability to zyg-1 mutants. Our data suggest that CK2 functions in cell division and negatively regulates centrosome duplication in a kinase-dependent manner. PMID:27881437

  17. Identification of a novel crosstalk between casein kinase 2α and NPM-ALK in ALK-positive anaplastic large cell lymphoma.

    Science.gov (United States)

    Armanious, Hanan; Gelebart, Pascal; Anand, Mona; Lai, Raymond

    2013-02-01

    It was previously reported that β-catenin contributes to the tumorigenesis of ALK-positive anaplastic large cell lymphoma (ALK(+)ALCL), and the oncogenic effects of β-catenin in these tumors are promoted by NPM-ALK, an abnormal fusion protein characteristic of ALK(+)ALCL. In this study, we hypothesized that NPM-ALK promotes the oncogenic activity of β-catenin via its functional interactions with the Wnt canonical pathway (WCP). To test this hypothesis, we examined if NPM-ALK modulates the gene expression of various members in the WCP. Using a Wnt pathway-specific oligonucleotide array and Western blots, we found that the expression of casein kinase 2α (CK2α) was substantially downregulated in ALK(+)ALCL cells in response to siRNA knockdown of NPM-ALK. CK2α is biologically important in ALK(+)ALCL, as its inhibition using 4,5,6,7-tetrabromobenzotriazole or siRNA resulted in a significant decrease in cell growth and a substantial decrease in the β-catenin protein level. Furthermore, CK2α co-immunoprecipitated with NPM-ALK and regulated its level of serine phosphorylation, a feature previously shown to correlate with the oncogenic potential of this fusion protein. To conclude, this study has revealed a novel crosstalk between NPM-ALK and CK2α, and our data supports the model that these two molecules work synergistically to promote the tumorigenicity of these lymphomas.

  18. Stability of the Human Hsp90-p50Cdc37 Chaperone Complex against Nucleotides and Hsp90 Inhibitors, and the Influence of Phosphorylation by Casein Kinase 2

    Directory of Open Access Journals (Sweden)

    Sanne H. Olesen

    2015-01-01

    Full Text Available The molecular chaperone Hsp90 is regulated by co-chaperones such as p50Cdc37, which recruits a wide selection of client protein kinases. Targeted disruption of the Hsp90-p50Cdc37 complex by protein–protein interaction (PPI inhibitors has emerged as an alternative strategy to treat diseases characterized by aberrant Hsp90 activity. Using isothermal microcalorimetry, ELISA and GST-pull down assays we evaluated reported Hsp90 inhibitors and nucleotides for their ability to inhibit formation of the human Hsp90β-p50Cdc37 complex, reconstituted in vitro from full-length proteins. Hsp90 inhibitors, including the proposed PPI inhibitors gedunin and H2-gamendazole, did not affect the interaction of Hsp90 with p50Cdc37 in vitro. Phosphorylation of Hsp90 and p50Cdc37 by casein kinase 2 (CK2 did not alter the thermodynamic signature of complex formation. However, the phosphorylated complex was vulnerable to disruption by ADP (IC50 = 32 µM, while ATP, AMPPNP and Hsp90 inhibitors remained largely ineffective. The differential inhibitory activity of ADP suggests that phosphorylation by CK2 primes the complex for dissociation in response to a drop in ATP/ADP levels. The approach applied herein provides robust assays for a comprehensive biochemical evaluation of potential effectors of the Hsp90-p50Cdc37 complex, such as phosphorylation by a kinase or the interaction with small molecule ligands.

  19. Reduced β-lactoglobulin IgE binding upon in vitro digestion as a result of the interaction of the protein with casein glycomacropeptide.

    Science.gov (United States)

    Martinez, María J; Martos, Gustavo; Molina, Elena; Pilosof, Ana M R

    2016-02-01

    The aim of this work was to evaluate the effect of the presence of casein glycomacropeptide (CMP) on the in vitro digestibility and potential allergenicity of β-lactoglobulin (β-lg)-CMP mixtures. The digestion products were analyzed by RP-HPLC and RP-HPLC-ESI-MS/MS. The potential allergenicity of the digestion products was studied by human IgE binding by inhibition ELISA with serum samples from children with clinical allergic symptoms to β-lg. No differences were observed by HPLC in the mixtures hydrolysates due to CMP-β-lg interactions. RP-HPLC-ESI-MS/MS results showed different peptides occurring in the mixtures hydrolysates. Additionally, it was observed a significant reduction of β-lg IgE binding in the presence of CMP. The disappearance of epitopes in the digested mixtures could explain the lower IgE binding observed in these systems compared to β-lg. It can be concluded that the presence of CMP in products containing β-lg may modify the digestion products that may reduce the potential allergenicity of β-lg.

  20. Formation and functional attributes of electrostatic complexes involving casein and anionic polysaccharides: An approach to enhance oral absorption of lycopene in rats in vivo.

    Science.gov (United States)

    Jain, Ashay; Thakur, Deepika; Ghoshal, Gargi; Katare, O P; Singh, Bhupinder; Shivhare, U S

    2016-12-01

    The current work entails a novel strategy of formulating the microparticles of lycopene solely using rational blends of biopolymers without using equipment-intensive techniques. The study is intended to enhance oral bioavailability of lycopene by controlling its release from micro-formulation and facilitating its absorption though lymphatic pathways. Considering the minimum particle size, maximum entrapment efficiency and loading capacity, the amounts of casein (i.e., protein) and gum tragacanth (i.e., polysaccharide) were selected as the critical factors for formulation of microparticles. Complex formation and electrostatic interaction was confirmed by Fourier transform infra red (FTIR) spectra. Size and surface properties of microparticles were studied using scanning electron microscopy (SEM). The optimized formulation (mean particle size: ∼130μm; % entrapment efficiency: ∼67% and loading capacity: ∼71%) designated noticeable improvement in lycopene release profile (over 80% in 24h). Increment in the values of Cmax (2.22-fold) and AUC (1.97-fold) further indicated noteworthy augmentation in the rate and extent of bioavailability by the microparticles formulation compared to plain lycopene. The resulting formulation was found to be quite stable all through two months of study episode. The resultant microparticles formulation was evaluated for antioxidant activity and tested for their effectiveness in self life enhancement of vegetable oil by calculating peroxide value under temperature and storage condition. Encapsulation strongly increased the stability of micronutrients. The current investigations, therefore, report the successful development of biopolymeric microparticles with improved bioavailability potential of lycopene.