Validation of a method employing liquid chromatography to identify and quantify glycomacropeptide of casein in raw milk / Validación de un método mediante cromatografía líquida para identificar y cuantificar glicomacropéptido de caseína en la leche cruda

Background: The information on official testing methods, or regulatory methods in Colombia to test whey in milk is limited; this restriction of information goes against the possibility of mitigating the risk of food fraud. Objectives: The validation of an HPLC method to determine casein glycomacropeptide (c-GMP), a protein that countries such as Brazil, Spain, and Ecuador have used as an indicator of raw milk adulteration with whey, was carried out. Methods: A 10mL sample of raw milk is precipitated with 24% TCA using ultrasound, a process followed by filtration. The collected fraction ensured the separation of c-GMP and then injected into the liquid chromatography. Results: A 30 minutes analysis allowed the determination of c-GMP with a retention time of 12.9 ± 0.5 minutes. The performance characteristics method in the validation exercise were: recovery percentage 99.97%, linearity R2> 0.95; % RSD accuracy <5.3%. Conclusion, the method exhibits desirable attributes for the intended purpose

Antecedentes: En Colombia la información de dominio público en metodologías de análisis de lactosuero en leche es limitada, restringiendo la posibilidad de acceder a ellas para mitigar el riesgo de fraude alimentario. Objetivos: Se realizó validación de un método por HPLC para determinar en leche cruda c-GMP, proteína usada como indicador de adulteración en países como Brasil y Ecuador. Metodos: Una muestra de 10mL de leche cruda es precipitada con TCA al 24% empleando ultrasonido, proceso seguido por filtración. La fracción recolectada aseguró la separación del c-GMP para luego inyectar al cromatógrafo líquido. Resultados: La determinación de c-GMP permitió el análisis en 30 minutos con tiempo de retención de 12,9 ± 0,5 minutos. Las características de desempeño del método en el ejercicio de validación fueron: porcentaje de recuperación 99,97%, linealidad R2>0,95; precisión %RSD< 5,3%. Conclusión: el método al final del ejercicio exhibe atributos para el fin previsto

The Promising Efficacy of Probiotics, Casein Phosphopeptide and Casein Macropeptide as Dental Anticariogenic and Remineralizing Agents Part I; An In vitro Study

Objectives: To investigate the effect of different mixtures from nano casein phosphopeptides (CPP), amorphous calcium phosphate (ACP), probiotic Lactobacillus rhamnosus B-445 (L. rhamnosus) and casein glycomacropeptide (GMP) against Streptococcus mutans (S. mutans) growth and its adhesion. Methods: CPP was prepared from the tryptic digest of bovine casein and GMP by the action of chymosin on casein solution. Four mixtures namely: Group 1) Nano CPP; Group 2) Nano CPP+ ACP; Group 3)Nano CPP+ ACP + L. rhamnosus; and Group 4)Nano CPP+ ACP+ GMP were prepared and tested for its inhibitory activity against S. mutans growth and its adhesion to saliva-treated glass surfaces in comparison with a commercial product (GC MI paste plus) and chlorhexidine (0.2%) as a positive control.  The particle size and zeta potential of nano CPP and its complex with ACP were evaluated. Furthermore, the viability of L. rhamnosusin its mixture was determined during two weeks of storage at pH 6.8 and 8 respectively. Results: Revealed that Nano CPP had an average particle size (7.75 nm) and zeta potential (-8.43 mV) lower than that of CPP+ACP mixture. Probiotic containing mixture exhibited inhibitory activity slightly less than the positive control at pH 6.8. All tested mixtures reduced the adhesion of S. mutans to saliva-treated glass surfaces and the highest was that containing probiotic and GMP. L. rhamnosus showed acceptable stability in CPP+ACP mixture during storage period. Conclusions: All these findings suggest the use of probiotic, CPP+ACP mixture as a dental anticariogenic and remineralizing agents.