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Abstract This study aimed to evaluate in vitro the effect protocols and anticaries agents containing casein amorphous calcium fluoride phosphopeptide-phosphate (CPP-ACPF, MI Paste Plus), sodium trimetaphosphate (TMP) and fluoride (F), in remineralization of caries lesions. Bovine enamel blocks with initial caries lesions were divided into groups (n = 12): 1) Toothpaste without F-TMP-MI Plus (Placebo); 2) Toothpaste 1100 ppm F (1100F), 3) 1100F + MI Paste Plus (1100F-MI Paste Plus), 4) Toothpaste with 1100F + Neutral gel with 4,500 ppm F + 5%TMP (1100F + Gel TMP) and 5) Toothpaste with 1100F + Neutral gel with 9,000 ppm F (1100F + Gel F). For the 4 and 5 groups the gel was applied only once for 1 minute, initially to the study. For the 3 group, after treatment with 1100F, MI Paste Plus was applied 2x/day for 3 minute. After pH cycling, the percentage of surface hardness recovery (%SHR); integrated loss of subsurface hardness (ΔKHN); profile and depth of the subsuperficial lesion (PLM); concentrations of F, calcium (Ca) and phosphorus (P) in enamel was determined. The data were analyzed by ANOVA (1-criterion) and Student-Newman-Keuls test (p < 0.001). Treatment with 1100F alone led to ~ 28% higher remineralization when compared to treatment with 1100F associated with MI Paste Plus (p < 0.001). The 1100F and 1100F + Gel F groups showed similar values for %SHR (p = 0.150). 1100F + Gel TMP treatment also remineralized the enamel surface by ~ 30% and 20% when compared to the 1100F + Gel F and 1100F groups (p < 0.001). The lower lesion depth (ΔKHN) was observed for the 1100F + Gel TMP group (p < 0.001), where it was 54% and 44% lower in comparison to the 1100F and 1100F + Gel F groups (p < 0.001). Polarized light microscopy photomicrographs showed subsurface lesions in all groups, but these lesions were present to a lower extent in the 1100F + Gel TMP group (p < 0.001). Treatment with 1100F + Gel TMP promoted an increase in the concentration of Ca in the enamel by ~ 57% and ~ 26% when compared to the 1100F and 1100F + MI Paste Plus groups (p < 0.001), respectively. There were no significant differences between the 1100F, 1100F + MI Paste Plus and 1100F + Gel F groups (p > 0.001). Similar values of P in the enamel were observed in the 1100F, 1100F + MI Paste Plus and 1100F + Gel F groups (p > 0.001), except for the 1100F + Gel TMP group, which presented a high concentration (p < 0.001). We conclude that the 1100F+TMP gel treatment/protocol led to a significant increased remineralization when compared to the other treatments/protocols and may be a promising strategy for patients with early caries lesions.

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BACKGROUND: Dental caries is considered one of the most common oral health diseases. OBJECTIVES: The aim of the study was to evaluate the effects of an experimental chitosan/casein gel on enamel demineralization/remineralization in an environment with a high cariogenic challenge. MATERIAL AND METHODS: Thirty-six specimens of bovine enamel (4 mm × 3 mm × 2 mm) were ground flat and polished. Then, the specimens were immersed in acetate buffer for 43 h with half of the surface protected (serving as control) and the other half exposed. All demineralized surfaces were randomly assigned into 3 groups (n = 12 per group) according to the type of treatment (G1 - control, G2 - 1.5% chitosan gel with 1.5% casein, and G3 - 1.5% chitosan gel without casein), and the corresponding treatment was applied once a week for 3 weeks. The specimens were also subjected to pH cycles of demineralization/ remineralization and the treatments were performed 3 times at 7-day intervals for a total of 21 days. Surface images were obtained for the analysis of initial roughness and, after the cariogenic challenge, new images were obtained to evaluate the final roughness, volume loss and wear profile using laser confocal microscopy. After the analyses, the specimens were cut and the depth of demineralization was measured. The data were analyzed using the Kruskal-Wallis analysis of variance (ANOVA) and the Tukey's test. RESULTS: While the chitosan gel with casein showed a similar loss to the control group (p > 0.05), both gels resulted in similar volume loss (p > 0.05). There were no statistical differences regarding the wear profile, surface roughness and depth of demineralization between the groups (p > 0.05). CONCLUSIONS: The chitosan gel reduced volume loss of the demineralized enamel without significantly impacting the surface smoothness.

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Of the diversity of proteins and high digestibility, goat milk will be a food of significant value for infant nutrition. The genetic polymorphisms of milk proteins play an essential role in the different degrees of allergic reactions. This work aimed to identify the proteins and peptides in the composition of goat milk and compare them to those in cow's milk. The work was performed with goats French Alpine, Nubian, and Creole breeds and Holstein Friesian milking cows at the Universidad Autónoma de Querétaro, Amazcala. We investigated the relative abundance of goat and cow milk protein fractions by SDS-PAGE resolution and the densitometric analysis of gels. The protein alfa-casein was (17.67 ± 0.46) for Creole, (19.18 ± 0.88) French Alpine, (17.35 ± 0.49) Nubian, and (35.92 ± 1.96) Holstein cows. The relative abundance obtained from alfa-casein was statistically different between goats and cows, and this protein was vital because it is a protein related to allergies. On the other hand, the amino acid in position 67 of the beta-casein from three goat breeds is a Proline, so it is assumed that the beta-casein variant of goat milk is an A2-type. The latter has excellent relevance for infant nutrition and differs from cow milk.

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We hypothesized that the general control nonderepressible 2 (GCN2)/eukaryotic initiation factor 2 (eIF2) signaling pathway and intracellular protein synthesis (PS) are regulated to maintain milk PS in primary bovine mammary epithelial cells (MECs) under essential amino acid (EAA) starvation conditions. We cultured MECs with 0%, 2% (depletion), and 100% (control) EAA for two exposure times (8 and 24 h), followed by three refeeding (RF) times with 100% EAA (0, 8, and 24 h). Subsequently, we measured cell viability, total protein concentration, and proliferation. Western blotting was used to quantify the levels of casein and the expression of total GCN2 and eIF2, as well as phosphorylated GCN2 (GCN2P) and eIF2 (eIF2P). The ISOQuant method was used to assess MEC proteomes, and the resultant data were analyzed using the Kruskal−Wallis test, nonpaired Wilcoxon rank post-hoc test, and ANOVA−Tukey test, as well as principal component analyses and multiple regressions models. Differences in cell viability were observed between the control versus the depleted and repleted MECs, respectively, where 97.2−99.8% viability indicated low cell death rates. Proliferation (range, 1.02−1.55 arbitrary units (AU)) was affected by starvation for 12 and 24 h and repletion for 24 h, but it was not increased compared with the control. Total protein expression was unaffected by both depletion and repletion treatments (median 3158 µg/mL). eIF2P expression was significantly increased (p < 0.05) after treatment with 2% EAA for 8 and 24 h compared with 2% EAA with 8 h + 24 h RF and 2% EAA with 24 h + 8 h RF. GCN2P also showed significantly increased expression (p < 0.05) after treatment with 2% EAA for 24 h compared with the control and 2% EAA with 24 h + 8 h RF. Intracellular casein/α-tubulin expression was unaffected by 2% EAA compared with control (0.073 ± 0.01 AU versus 0.086 ± 0.02 AU, respectively). We studied 30 of the detected 1180 proteins, 16 of which were differentially expressed in starved and refed MECs. Cells faced with EAA deficiency activated the GCN2P/eIF2P pathway, and the lack of change in the levels of casein and other milk proteins suggested that the EAA deficit was mitigated by metabolic flexibility to maintain homeostasis.

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The present study aims to describe colloidal and acid gelling properties of mixed suspensions of pea and milk proteins. Mixed protein suspensions were prepared by adding pea protein isolate to rehydrated skimmed milk (3% w/w protein) to generate four mixed samples at 5, 7, 9, and 11% w/w total protein. Skimmed milk powder was also used to prepare four pure milk samples at the same protein concentrations. The samples were analyzed in regard to their pH, viscosity, color, percentage of sedimentable material, heat and ethanol stabilities, and acid gelling properties. Mixed suspensions were darker and presented higher pH, viscosity, and percentage of sedimentable material than milk samples. Heat and ethanol stabilities were similar for both systems and were reduced as a function of total protein concentration. Small oscillation rheology and induced syneresis data showed that the presence of pea proteins accelerated acid gel formation but weakened the final structure of the gels. In this context, the results found in the present work contributed to a better understanding of mixed dairy/plant protein functionalities and the development of new food products.

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Infant formulas, designed to provide similar nutritional composition and performance to human milk, are recommended when breastfeeding is not enough to provide for the nutritional needs of children under 12 months of age. In this context, the present study aimed to assess the protein quality and essential amino acid content of both starting (phase 1) and follow-up (phase 2) formulas from different manufacturers. The chemical amino acid score and protein digestibility corrected by the amino acid score were calculated. The determined protein contents in most formulas were above the maximum limit recommended by FAO and WHO guidelines and at odds with the protein contents declared in the label. All infant formulas contained lactoferrin (0.06 to 0.44 g·100 g-1) and α-lactalbumin (0.02 to 1.34 g·100 g-1) below recommended concentrations, whereas ĸ-casein (8.28 to 12.91 g·100 g-1), α-casein (0.70 to 2.28 g·100 g-1) and ß-lactoglobulin (1.32 to 4.19 g·100 g-1) were detected above recommended concentrations. Essential amino acid quantification indicated that threonine, leucine and phenylalanine were the most abundant amino acids found in the investigated infant formulas. In conclusion, infant formulas are still unconforming to nutritional breast milk quality and must be improved in order to follow current global health authority guidelines.

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Introduction: Sodium caseinate (CS) and its components (alpha-casein, beta-casein, and kappa-casein) have been shown to inhibit the proliferation of the mouse hematopoietic 32D clone 3 (32Dcl3) cell line and induce its differentiation into macrophages. It is well-known that alpha-casein induces IL-1ß production and that this cytokine inhibits the proliferation via the production of tumor necrosis factor alpha (TNF-alpha), but it is not known if CS and the caseins inhibit the proliferation via TNF-alpha production. Objective: To evaluate if CS and alpha-casein, beta-casein and kappa-casein inhibit the proliferation on 32Dcl3 cell line via TNF-alpha. Materials and methods: We used different concentrations of CS, alpha-casein, betacasein and kappa-casein in 32Dcl3 cells to evaluate cell proliferation. We assessed cell viability by MTT, induction to apoptosis by flow cytometry, and TNF-alpha synthesis by ELISA. Additionally, we performed anti-TNF-alpha neutralization assays on 32Dcl3 cells treated with CS and alpha-casein and we evaluated proliferation. Results: The results showed that CS, alpha-casein, beta-casein, and kappa-casein reduced proliferation of the 32Dcl3 cell line without affecting the viability and that only CS and alpha-casein induced apoptosis and the release of TNF-alpha. The 32Dcl3 cells treated with CS and alpha-casein reestablished their proliferation by using anti-TNF-alpha antibodies. Conclusion: TNF-alpha was the main responsible for the inhibition of proliferation in 32Dcl3 cells treated with CS or alpha-casein.

Introducción. Se ha demostrado que el caseinato de sodio y sus componentes (caseínas α, ß y κ) inhiben la proliferación de la línea celular hematopoyética de ratón 32D clone 3 (32Dcl3) e inducen su diferenciación hacia macrófagos. Se sabe que la caseína α induce la producción de IL-1ß y que esta última citocina inhibe la proliferación celular mediante la producción del factor de necrosis tumoral alfa (TNF-α), pero se desconoce si el caseinato de sodio y las caseínas inducen la producción de TNF y si este es el responsable de la inhibición de la proliferación. Objetivo. Evaluar si el caseinato de sodio y las caseínas α, ß y κ inhiben la proliferación de la línea celular 32Dcl3 mediante la producción de TNF-α. Materiales y métodos. Se usaron diferentes concentraciones de caseinato de sodio y de las caseínas α, ß y κ en las células 32Dcl3. Posteriormente, se evaluaron la viabilidad celular mediante una prueba con el MTT [3-(4,5-dimetiltiazol-2-ilo)-2,5-difeniltetrazol], la inducción de apoptosis con la citometría de flujo y la síntesis del TNF-α con el ELISA. Además, se hicieron pruebas de neutralización con anti-TNF-α en células 32Dcl3 tratadas con caseinato de sodio y caseína α, y se evaluó la proliferación celular. Resultados. Se encontró que el caseinato de sodio y las caseínas α, ß y κ reducían la proliferación de la línea celular 32Dcl3 sin afectar la viabilidad, y que solo el caseinato y la caseína α inducían la apoptosis y la liberación al medio de TNF-α. La proliferación de células 32Dcl3 tratadas con caseinato y caseína α se restableció al usar anticuerpos anti-TNF-α. Conclusión. El TNF-α fue el principal responsable de la inhibición de la proliferación en las células 32Dcl3 tratadas con caseinato de sodio o caseína α.

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Resumen Introducción. Se ha demostrado que el caseinato de sodio y sus componentes (caseínas α, β y κ) inhiben la proliferación de la línea celular hematopoyética de ratón 32D clone 3 (32Dcl3) e inducen su diferenciación hacia macrófagos. Se sabe que la caseína α induce la producción de IL-1β y que esta última citocina inhibe la proliferación celular mediante la producción del factor de necrosis tumoral alfa (TNF-α), pero se desconoce si el caseinato de sodio y las caseínas inducen la producción de TNF y si este es el responsable de la inhibición de la proliferación. Objetivo. Evaluar si el caseinato de sodio y las caseínas α, β y κ inhiben la proliferación de la línea celular 32Dcl3 mediante la producción de TNF-α. Materiales y métodos. Se usaron diferentes concentraciones de caseinato de sodio y de las caseínas α, β y κ en las células 32Dcl3. Posteriormente, se evaluaron la viabilidad celular mediante una prueba con el MTT [3-(4,5-dimetiltiazol-2-ilo)-2,5-difeniltetrazol], la inducción de apoptosis con la citometría de flujo y la síntesis del TNF-α con el ELISA. Además, se hicieron pruebas de neutralización con anti-TNF-α en células 32Dcl3 tratadas con caseinato de sodio y caseína α, y se evaluó la proliferación celular. Resultados. Se encontró que el caseinato de sodio y las caseínas α, β y κ reducían la proliferación de la línea celular 32Dcl3 sin afectar la viabilidad, y que solo el caseinato y la caseína α inducían la apoptosis y la liberación al medio de TNF-α. La proliferación de células 32Dcl3 tratadas con caseinato y caseína α se restableció al usar anticuerpos anti-TNF-α. Conclusión. El TNF-α fue el principal responsable de la inhibición de la proliferación en las células 32Dcl3 tratadas con caseinato de sodio o caseína α.

Abstract Introduction: Sodium caseinate (CS) and its components (alpha-casein, beta-casein, and kappa-casein) have been shown to inhibit the proliferation of the mouse hematopoietic 32D clone 3 (32Dcl3) cell line and induce its differentiation into macrophages. It is well-known that alpha-casein induces IL-1β production and that this cytokine inhibits the proliferation via the production of tumor necrosis factor alpha (TNF-alpha), but it is not known if CS and the caseins inhibit the proliferation via TNF-alpha production. Objective: To evaluate if CS and alpha-casein, beta-casein and kappa-casein inhibit the proliferation on 32Dcl3 cell line via TNF-alpha. Materials and methods: We used different concentrations of CS, alpha-casein, beta-casein and kappa-casein in 32Dcl3 cells to evaluate cell proliferation. We assessed cell viability by MTT, induction to apoptosis by flow cytometry, and TNF-alpha synthesis by ELISA. Additionally, we performed anti-TNF-alpha neutralization assays on 32Dcl3 cells treated with CS and alpha-casein and we evaluated proliferation. Results: The results showed that CS, alpha-casein, beta-casein, and kappa-casein reduced proliferation of the 32Dcl3 cell line without affecting the viability and that only CS and alpha-casein induced apoptosis and the release of TNF-alpha. The 32Dcl3 cells treated with CS and alpha-casein reestablished their proliferation by using anti-TNF-alpha antibodies. Conclusion: TNF-alpha was the main responsible for the inhibition of proliferation in 32Dcl3 cells treated with CS or alpha-casein.

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The aim of the present study was to explore the association between milk protein content and casein micelle size and to examine the effects of casein micelle size on enzymatic curd strength and dry matter curd yield using reduced laboratory-scale cheese production. In this research, 140 bulk tank milk samples were collected at dairy farms. The traits were analyzed using two linear models, including only fixed effects. Smaller micelles were associated with higher κ-casein and lower αs-casein contents. The casein micellar size (in the absence of the αs-casein and κ-casein effects) did not affect the enzymatic curd strength; however, smaller casein micelles combined with higher fat, lactose, casein and κ-casein contents exhibited a favorable effect on the dry matter curd yield. Overall, results of the present study provide new insights into the importance of casein micelle size for optimizing cheese production.(AU)

Este trabalho foi desenvolvido com o objetivo de investigar a associação da composição proteica do leite com o tamanho das micelas de caseína, e o efeito do TMCN sobre a firmeza do coágulo enzimático e da produção de massa seca do coágulo produzido em escala reduzida. Foram coletadas 140 amostras de leite cru de diferentes fazendas. Os dados foram analisados usando dois modelos lineares, incluindo somente efeitos fixos. Menores micelas de caseína foram associadas com maior conteúdo de k-caseína e menor conteúdo de αs-caseína. O tamanho das micelas de caseína sem o efeito da αs-caseína e k-caseína não apresentou efeito sobre a firmeza do coágulo, porém apresentou efeito significatico sobre a produção de massa seca do coágulo. Esses resultados demonstram a importância do tamanho das micelas de caseína para otimizar a produção de queijo.(AU)

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Objective: To determine and compare the remineralizing capacity of self-assembling peptide (SAP) P11-4 and casein phosphopeptides­amorphous calcium phosphate (CPP-ACP) on enamel. Material and Methods: Enamel samples were divided into 2 groups. Group I was treated with Self­assembling peptide (SAP) P11-4 and group II with casein phosphopeptides-amorphous calcium phosphate (CPP-ACP). In both groups, remineralizing capacity was assessed at baseline, 2 weeks, 6 weeks and 12 weeks. Student's t- test and ANOVA were applied, with the significance level set at 5%. Results: The mean calcium weight % was evaluated at baseline, 2 weeks, 6 weeks and 12 weeks. In Group I, there was increase in mean value (62.12 ± 1.24) from baseline to 12 weeks (67.36 ± 2.14). However, there was decrease in phosphate weight % from 37.16 ± 2.52 at baseline to 35.72 ± 2.11 at 12 weeks. In Group II, mean calcium weight % was 64.18 ± 1.52 at baseline, which ultimately increased to 66.01 ± 2.03 at 12 weeks. Phosphate weight % showed reduction from 37.34 ± 2.23 at baseline to 35.04 ± 2.02 at 12 weeks. Ca/P ratio showed significant improvement. There was significant difference in Ca/P ratio at 2 weeks, 6 weeks and 12 weeks in both groups (p<0.05). Conclusion: Self-assembling peptide (SAP) P11-4 found to be more effective and efficient as compared to casein phosphopeptides­amorphous calcium phosphate (CPP-ACP).

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Objective: To evaluate and compare the remineralization potential of a dentifrice containing bioactive glass and a topical cream containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) in remineralizing artificial carious lesion on enamel. Material and Methods: Forty-five freshly extracted human permanent premolar teeth were selected. Samples were divided into three groups: GI - regular tooth paste without specific remineralizing agent; GII - tooth paste containing calcium sodium-phosphosilicate (novamin) and GIII - topical cream containing casein phosphopeptide-amorphous calcium phosphate. All the sound enamel samples were viewed under scanning electron microscope (SEM) to assess the topographical pictures of enamel surface and energy dispersing x-ray analysis (EDAX) was done to estimate quantitatively the amounts of mineral (calcium and phosphorous). The mineral content of calcium and phosphorus after demineralization in each group was noted. The samples were then subjected to SEM and EDAX. Results: GI does not show any increase in the calcium and phosphorus after applying toothpaste without any remineralizing agent but GII and GIII showed a net increase in calcium and phosphorous values after applying concern-remineralizing agents. Inter group comparison showed GIII yield higher net calcium and phosphorous values than GII. Conclusion: Two remineralizing agents showed remineralization potential on enamel surfaces. Casein phosphopeptide-amorphous calcium phosphate showed better remineralizing potential than calcium sodium phosphosilicate. Hence CPP-ACP can be considered as the material of choice in remineralizing early enamel carious lesions.

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Objective: To evaluate in situ the effect of toothpastes containing casein phosphopeptide - amorphous calcium phosphate (CPP-ACP) and casein phosphopeptide-amorphous calcium phosphate associated to fluoride (CPP-ACPF) on initial erosion prevention. Material and Methods: Bovine enamel blocks (n = 192) were randomly assigned into 4 phases according to the baseline surface hardness: GI: CPP-ACP Paste (MI Paste™), GII: CPP-ACPF Paste (MI Paste Plus™), GIII: Fluoridated paste and GIV: Placebo Paste. In each of the 4 crossover phases, twelve volunteers wore intraoral palatal appliances containing 4 enamel blocks for 2 hours, then the tested treatments were applied intraorally (3 min) and the appliance was maintained in the mouth for another 3 hours. After, the appliances were removed and immersed in hydrochloric acid (0.01 M, pH 2.3) for 30 seconds to promote erosive demineralization. The final surface hardness was evaluated and percentage of surface hardness loss was calculated. The data were analyzed by ANOVA and Tukey's test (α = 5%). Results: The application of CPP-ACP paste, independent of fluoride content, resulted in significant lower enamel hardness loss (GI: 9.26% ±3.48 and GII: 9.14% ±1.73) compared to NaF (GIII: 15.5% ± 3.94) and placebo (GIV: 16.7% ± 4.07) pastes, which did not show difference between them. Conclusion: The CPP-ACP pastes were able to reduce initial erosive demineralization in relation to fluoride and placebo pastes. Nevertheless the formulation of CPP-ACP with fluoride did not provide an additional benefit.

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ABSTRACT The objective of this study was to report the clinical treatment of a child with Incisor Molar Hipomineralization. A 5-year-old Brazilian child, male gender, was diagnosed with Molar Incisor Hypomineralization, reporting high teeth sensitivity. After anamnesis and clinical examination, treatment was conducted with three weekly applications of fluoride varnish containing 5% CPP-ACP complex. Also, it was advice to the patient for using a toothpaste containing fluoride and CPP-ACP (MI Paste Plus). After that, molars with great tooth structure loss were restored with resin modified glass ionomer cement. Prior to the first topical application of varnish with CPP-ACP and fluoride toothpaste containing CPP-ACP, a sensitivity test was conducted using thermal stimulus and facial pain scale. It was observed relative sensitivity decrease between sessions, reporting no sensitivity at the last session before the restoration. The treatment of Molar Incisor Hypomineralization teeth with CPP-ACP complex associated with fluoride varnish can be an alternative to reduce sensivity.

RESUMO O objetivo desse estudo foi relatar o tratamento clínico de uma criança com Hipomineralização Molar Incisivo e, portanto, alto índice de sensibilidade dentária. Uma criança de cinco anos de idade, do gênero masculino, foi diagnosticada com Hipomineralização Molar Incisivo, relatando alta sensibilidade dentária. Após a anamnese e exame clínico, o tratamento iniciou-se com três aplicações de verniz fluoretado a 5% com complexo de CPP-ACP, associado à um dentifrício fluoretado contendo CPP-ACP (MI Paste Plus), em intervalos semanais. Após as três sessões de aplicação de verniz, os molares com grande perda de estrutura dentária foram restaurados com cimento de ionômero de vidro modificado por resina (Vitremer). Previamente à primeira aplicação tópica do verniz fluoretado com CPP-ACP e utilização do dentifrício fluoretado contendo CPP-ACP foi realizado um teste de sensibilidade dentária usando estímulo térmico e escala facial de dor, repetindo-se a cada sessão. Verificou-se que a sensibilidade diminuiu entre as sessões, com ausência de sensibilidade na última sessão antes da restauração. O tratamento de dentes com Hipomineralização Molar Incisivo utilizando-se o complexo CPP-ACP associado à aplicação tópica de flúor pode ser uma alternativa para redução da sensibilidade dentária.

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ABSTRACT: The aim of the present study was to explore the association between milk protein content and casein micelle size and to examine the effects of casein micelle size on enzymatic curd strength and dry matter curd yield using reduced laboratory-scale cheese production. In this research, 140 bulk tank milk samples were collected at dairy farms. The traits were analyzed using two linear models, including only fixed effects. Smaller micelles were associated with higher κ-casein and lower αs-casein contents. The casein micellar size (in the absence of the αs-casein and κ-casein effects) did not affect the enzymatic curd strength; however, smaller casein micelles combined with higher fat, lactose, casein and κ-casein contents exhibited a favorable effect on the dry matter curd yield. Overall, results of the present study provide new insights into the importance of casein micelle size for optimizing cheese production.

RESUMO: Este trabalho foi desenvolvido com o objetivo de investigar a associação da composição proteica do leite com o tamanho das micelas de caseína, e o efeito do TMCN sobre a firmeza do coágulo enzimático e da produção de massa seca do coágulo produzido em escala reduzida. Foram coletadas 140 amostras de leite cru de diferentes fazendas. Os dados foram analisados usando dois modelos lineares, incluindo somente efeitos fixos. Menores micelas de caseína foram associadas com maior conteúdo de k-caseína e menor conteúdo de αs-caseína. O tamanho das micelas de caseína sem o efeito da αs-caseína e k-caseína não apresentou efeito sobre a firmeza do coágulo, porém apresentou efeito significatico sobre a produção de massa seca do coágulo. Esses resultados demonstram a importância do tamanho das micelas de caseína para otimizar a produção de queijo.

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The present work examined the role of Tyr and Trp in oxidative modifications of caseins, the most abundant milk proteins, induced by peroxyl radicals (ROO•). We hypothesized that the selectivity of ROO• and the high flexibility of caseins (implying a high exposure of Tyr and Trp residues) would favor radical-radical reactions, and di-tyrosine (di-Tyr) and di-tryptophan (di-Trp) formation. Solutions of α- and ß-caseins were exposed to ROO• from thermolysis and photolysis of AAPH (2,2'-azobis(2-methylpropionamidine)dihydrochloride). Oxidative modifications were examined using electrophoresis, western blotting, fluorescence, and chromatographic methodologies with diode array, fluorescence and mass detection. Exposure of caseins to AAPH at 37 °C gave fragmentation, cross-linking and protein aggregation. Amino acid analysis showed consumption of Trp, Tyr, Met, His and Lys residues. Quantification of Trp and Tyr products, showed low levels of di-Tyr and di-Trp, together with an accumulation of carbonyls indicating that casein aggregation is, at least partly, associated with secondary reactions between carbonyls and Lys and His residues. AAPH photolysis, which generates a high flux of free radicals increased the extent of formation of di-Tyr in both model peptides and α- and ß- caseins; di-Trp was only detected in peptides and α-casein. Thus, in spite of the high flexibility of caseins, which would be expected to favor radical-radical reactions, the low flux of ROO• generated during AAPH thermolysis disfavours the formation of dimeric radical-radical cross-links such as di-Tyr and di-Trp, instead favoring other O2-dependent crosslinking pathways such as those involving secondary reactions of initial carbonyl products.

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Type I photo-oxidation generates Trp-(TrpN) and Tyr-derived (TyrO) radicals in proteins which can dimerize producing cross-links, or alternatively react with O2. It was therefore hypothesized that the O2 concentration may have a significant effect on dye-photosensitized reactions. We studied photo-oxidation of α- and ß-caseins induced by riboflavin (RF), a photosensitizing vitamin present in milk, under aerobic and anaerobic conditions. Triplet-state RF induced oxidative modifications on both caseins, and significant levels of cross-links. The extent of damage, and the yield of cross-links versus oxidized products, was dependent on the O2 concentration. In the absence of O2, the overall extent of damage was decreased, but the yield of cross-linked products was significantly elevated. These cross-links are consistent with inter- and intra-molecular di-Tyr or di-Trp bridges. Alternative cross-links were detected in the presence of O2, consistent with pathways involving the reaction of protein radicals with O2 or O2-.

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Casein and whey proteins with and without heat treatment were obtained of whole milk and four commercial milks in Ecuador, and were hydrolyzed. Then, their capacity to inhibit the lipid peroxidation using the TBARS method was evaluated at concentrations of 0.02, 0.04, 0.2, and, 0.4 mg/mL. Native and heated hydrolysates of milk proteins present high inhibitions of lipid peroxidation with a dose dependent effect both in vivo and in vitro tests. Casein and whey proteins obtained from whole milk were the ones with the highest anti-oxidant activity in vitro and in vivo test. Native casein hydrolysate at 0.4 mg/mL present a value of 55.55% of inhibition of lipid peroxidation and heated casein hydrolysate at 0.4 mg/mL presents a value of 58.00% of inhibition of lipid peroxidation. Native whey protein at 0.4 mg/mL present a value of 34.84% of inhibition of lipid peroxidation, and heated whey protein at 0.4 mg/mL presents a value of 40.86% of inhibition of lipid peroxidation. Native and heated casein hydrolysates were more active than native and heated whey protein hydrolysates. Heat treatments have an effect of increasing the in vitro inhibition of lipid peroxidation of hydrolysates of milk protein. Casein and whey hydrolysates were able to inhibiting lipid peroxidation in the zebrafish larvae model. Native casein hydrolysate obtained of whole milk presents 48.35% of inhibition TBARS in vivo, this activity was higher in heated casein hydrolysate obtained of whole milk with a value of 56.28% of inhibition TBARS in vivo. Native whey protein hydrolysate obtained of whole milk presents 35.30% of inhibition TBARS, and heated whey protein hydrolysate obtained of whole milk was higher, with a value of 43.60% of inhibition TBARS in vivo.

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Abstract: The study aimed to investigate the effects of bacterial biofilms on changes in the surface microhardness of enamel treated with casein phosphopeptide—amorphous calcium phosphate (CPP-ACP) with and without fluoride. Human enamel blocks with incipient caries-like lesions were divided into four groups of 13: G1: Saliva (Control); G2: fluoride dentifrice (Crest™, 1100 ppm as NaF); G3: CPP-ACP (MI Paste; Recaldent™); and G4: CPP-ACPF (MI Paste Plus; Recaldent™ 900 ppm as NaF). The specimens were soaked in demineralizing solution for 6 h and remineralized in artificial saliva for 18 h alternately for 10 days. The dentifrice was prepared with deionized water in a 1 : 3 ratio (w/w) or applied undiluted in the case of the CPP-ACP group. The surface microhardness (SMH) was evaluated at baseline, after artificial caries, after pH cycling and treatment with dentifrices, and after incubation in media with Streptococcus mutans for biofilm formation. The biofilms were exposed once a day to 2% sucrose and the biofilm viability was measured by MTT reduction. The percentage of change in surface microhardness (%SMHC) was calculated for each block. The data were analyzed by nonparametric test comparisons (α = 0.05). The %SMHC values observed in G2 were different from those of G1, G3, and G4 (p < 0.05). After biofilm formation, %SMHC was positive in G2 and G4 when compared to G1 and G3, but resistance to demineralization after biofilm formation was similar in all groups. In conclusion, the presence of biofilms did not influence the treatment outcomes of anticaries products.

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Objetivo: A associação entre leite e cárie dentária ainda é objeto de debate. Nesta scoping review, verificou-se a relação entre ingestão de leite e laticínios e a prevenção da cárie dentária. Material e método: Foi realizada pesquisa bibliográfica, a partir de consulta a artigos indexados nas bases de dados PubMed, Scielo e Lilacs publicados entre 2006 e janeiro/2016, incluindo estudos clínicos e laboratoriais, publicados nas línguas inglês, português e espanhol. Resultados: Dentre as 96 publicações inicialmente identificadas, apenas seis contemplaram os critérios de inclusão e exclusão. Os artigos apresentaram metodologias diversas que investigaram o efeito do leite, caseína, proteína do soro e compostos à base de fosfopeptídeos da caseína e fosfato de cálcio amorfo. O efeito preventivo dessas substâncias foi mais observado em crianças e em amostras de dentes extraídos. Conclusão: A diversidade metodológica dificultou comparações e conclusões, mas apontou para o potencial do uso do leite e laticínios no controle da cárie.

Aim: The association between milk and dental caries remains controversial. In this scoping review, we checked the relation between intake of milk and dairy products with the prevention of dental caries. Material and Methods: The literature search followed the protocol based on papers indexed in the databases PubMed, Scielo and Lilacs, published between 2006 and January/2016, including clinical studies and laboratories, published in English, Portuguese and Spanish. Results: Among the 96 publications initially identified, only six contemplated the inclusion and exclusion criteria. The papers showed diversities of methodologies that investigate the effect of milk, casein, whey protein and protein compounds of casein phosphopeotidies and amorphous calcium phosphate. The preventive effect of those substances was more observed in children and in samples of extracted teeth. Conclusion: The methodological diversity of studies hampers the comparisons and conclusions, but pointed out to a potential use of milk and dairy products in the control of dental caries.

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Objective: To evaluate salivary flow and buffer capacity by means of mechanical and chemical-mechanical stimuli, through the use of chewing gums. Material and Methods: The study was a cross-sectional study with 12 volunteers, divided into three groups, in three phases: Group A: paraffin gum; Group B: Chewing gum without sucrose, flavored (Trident®); Group C: Flavored chewing gum, without sucrose and amorphous calcium casein-phosphate phosphopeptide (Trident Total®). The stimulated total saliva was collected after 5 minutes of mastication of one of the products and the volume was expressed in mL / min. The same sample was submitted to pH measurement with the use of a digital potentiometer, where the results were classified in normal buffer capacity (final pH between 5.0 and 7.0) or low (final pH <4.0). The results were evaluated regarding the normality of the sample distribution (Shapiro-Wilk test), Analysis of Variance (ANOVA) and Tukey's test. Results: Chewing gums increased the salivary flow of the volunteers, when compared to the control group (paraffin) (1.53 mL / min), differing statistically from the group, although there was no difference between Trident® (2.09 mL / Min) and Trident Total® (2.06mL / min). Regarding the buffer capacity, the values obtained were 6.94 (paraffin), 6.99 (Trident®) and 6.93 (Trident Total®), with no difference between groups (p = 0.713). Conclusion: It was concluded that chewing gums, with and without CPP-ACP, increased the salivary flow in relation to the control group. In relation to buffer capacity the values obtained for chewing gums with and without CPP-ACP, are shown to be within the normal range.

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