Investigation of the effect of breast milk, probiotic supplemented and plain milk formulas on some oral bacteria in infants: an observational and in-vitro study / Investigação do efeito do leite materno, fórmulas de leite puro e suplementado com probióticos sobre algumas bactérias orais em lactentes: um estudo observacional e in vitro

Objetivo: existem evidências inconclusivas sobre a potencial carogenicidade das fórmulas lácteas em comparação com o leite materno. O estudo teve como objetivo comparar a detecção e contagem de Streptococcus mutans(S. mutans) e lactobacilos da saliva entre lactentes alimentados com leite materno (B), com fórmulas de leite puro (France Lait-FL) e suplementada com probióticos (Nan 1 optipro-N), e avaliar crescimento in vitro dessas bactérias em amostras de leite materno e fórmulas lácteas. Material e Métodos: amostras salivares foram obtidas com swabs de algodão estéreis de 60 lactentes que foram agrupados de acordo com o tipo de leite. As amostras foram cultivadas para obter a frequência de detecção e contagens bacterianas. Para a investigação in vitro, sete amostras de leite materno doado e sete amostras recém-preparadas de ambas as fórmulas lácteas foram inoculadas por ambas as bactérias e então cultivadas para avaliar o crescimento bacteriano. Resultados:lactobacilos foram detectados em todos os lactentes, enquanto não foram encontradas diferenças significativas na detecção de S. mutans entre os grupos. As contagens de ambos os microrganismos na saliva foram menores em (B), enquanto uma diferença insignificante foi encontrada entre (B) e (N). Diferenças significativas foram evidentes nas contagens bacterianas in vitro sendo mais baixas em (B) seguido por (N) e (FL). Conclusão: o leite materno e as fórmulas lácteas com suplementos probióticos podem ter um papel protetor contra a cárie dentária em lactentes. (AU)

Objective: inconclusive evidence exists regarding potential cariogenicity of milk formulas compared to breast milk. The study aimed to compare Salivary Streptococcus mutans (S. mutans) and lactobacilli detection and counts among breastfed (B), plain formula (France Lait 1) (FL) and probiotic supplemented formula (Nan 1 optipro) (N) infants and to assess in-vitro growth of these bacteria in breast milk and milk formula samples. Material and Methods:salivary samples were obtained using sterile cotton swabs from 60 infants that were grouped according to nursing milk type. Samples were cultured to obtain the detection frequency and bacterial counts. For the in-vitro investigation, seven donated breast milk samples and seven freshly prepared samples of both milk formulas were inoculated by both bacteria and then cultured to assess bacterial growth. Results:lactobacilli were detected in all infants, while no significant differences were found in S. mutans detection among groups. Counts of both microorganisms in saliva were lowest in (B) while, insignificant difference was found between (B) and (N). Significant differences were evident in in-vitro bacterial counts being lowest in (B) followed by (N) and (FL). Conclusion: breast milk and probiotic supplement infants' milk formulas may have a protective role against dental caries in infants.(AU)

Efecto de la temperatura de refrigeración y calentamiento de fórmulas lácteas Infantiles en el crecimiento de cronobacter sakazakii / Effect of temperature cooling and heating of powered infant formula on the growth of cronobacter sakazakii

Cronobacter sakazakii (C. sakazakii) es un microorganismo perteneciente a la familia Enterobacteriaceae asociado con patologías como meningitis y septicemia en recién nacidos. Las fórmulas lácteas infantiles (FLI) han sido reconocidas como el vehículo más importante de transmisión de C. sakazakii, por condiciones inadecuadas durante su producción o preparación. El objetivo de la presente investigación fue evaluar el efecto de la temperatura de refrigeración y el calentamiento de las FLI en el crecimiento de C. sakazakii. Las muestras de FLI reconstituidas se contaminaron con 102, 104 y 106 UFC/mL de C. sakazakii y se refrigeraron durante cuatro horas a 4°C, 6°C y 10°C, posterioriormente, se calentaron en baño hidrotérmico hasta 37°C. Las muestras fueron sembradas al tiempo “0” (postrefrigeración) y luego del calentamiento hasta 37°C en placas con agar cromogénico y se incubaron a 35°C por 24h. Para el análisis de los datos se utilizó la prueba de Wilcoxon. Según los datos obtenidos no hubo variación significativa en la población de C. sakazakii en las FLI luego de 4 horas en refrigeración a 4°C, 6°C y 10°C; sin embargo, al calentar las fórmulas hasta 37°C, hubo en todos los casos una reducción de un ciclo logarítmico en la población de C. sakazakii con un valor de p = 0.0056 y Z= 2.752. Se concluye que el calentamiento a 37°C post-refrigeracion de las muestras, disminuye la población de C. sakazakii en FLI (p<0,05)(AU)

Cronobacter sakazakii (C. sakazakii) is a microorganism belonging to the family Enterobacteriaceae associated with diseases such as meningitis and sepsis in newborns. The powdered infant formula (PIF) have been recognized as the most important vehicle of transmission of C. sakazakii, by inadequate conditions during production or during its preparation. The aim of this investigation was to assess the effect of the cooling temperature and the heating of PIF in the growth of C. sakazakii. For this, PIF reconstituted samples were contaminated with 102, 104 and 106 CFU / mL of C. sakazakii and refrigerated for four hours at 4 ° C, 6 ° C or 10 ° C after this hydrothermal bath heated to 37 ° C. Samples were cultured at time “0” (after- cooling) and then heating to 37 ° C in chromogenic agar plates and incubated at 35 ° C for 24h . For data analysis we used the Wilcoxon test. According to the data there was no significant variation in the population of C. sakazakii in PIF after 4 hours in the refrigerator at 4 ° C, 6°C and 10 ° C , however , by heating the formulas to 37 ° C , in all cases there was a reduction of one log cycle in population C. sakazakii with a value of p = 0.0056 and Z = 2.752 . We conclude that heating at 37°C post- cooling of the samples, decreases the population of C. sakazakii in FLI ( p < 0,05 )(AU)