María Elena Sambucetti

Lactoferrin levels in term and preterm milk.

Objective: Even though there is no doubt that human milk is the best nourishment for the neonate, there is still controversy regarding its suitability for preterm infants. The aim of this study was to contribute to the knowledge of the anti-infective properties of preterm milk, measuring lactoferrin levels, which are a non-specific protective factor. Methods: Samples from 26 preterm and 20 term mothers (mean gestational age±standard deviation, 30.9±2.6 and 39.5±1.1 weeks, respectively) were collected during the first month post-partum. Milk samples were obtained by total expression of one breast between 10 a.m. and noon. An aliquot was kept at −20°C until analyzed by SDS-PAGE (sodium dodecyl sulfate-polyacrylarnide gel electrophoresis). Each sample was run in duplicate. Results: Lactoferrin levels (X±SD) in colostrum and mature milk varied from 575.0±218.2 mg/dL to 459.4±190.7 mg/dL in preterm samples and from 970.6±288.6 mg/dL to 292.0±167.4 mg/dL in term samples. No significant differences were observed between preterm and term groups, in spite of the trend observed in colostrum, where term milk tended to show higher levels than preterm milk. Decreasing values were observed in both groups along time (ANOVA, p<0.05). However, in the preterm group, lactoferrin levels seemed to maintain rather constant values from the eighth post-partum day onwards. Conclusions: The trend to higher levels of lactoferrin in preterm mature milk would allow maintenance of the protective effect of human milk in preterm infants in spite of the small volumes ingested by these neonates. These findings support the practice of feeding premature infants with their own mothers’ milk at a time when their immune systems have not completely developed.

Effect of Gamma Irradiation on the Functional and Nutritive Properties of Rice Flours from Different Cultivars

ABSTRACT The purpose of this work was to study the effect of minimal doses of γ-irradiation to reduce microbial loads (Co60, doses of 0, 1.5, and 3 kGy) on flour from three rice cultivars with different amylose contents (AC) grown in Argentina: RP2 (AC 25%), Yerua (Y) (AC 19%), and Higokumochi (H) (AC 5%). Studies on some starch characteristics such as digestibility (rate of starch hydrolysis in vitro), gel viscosity and syneresis, and scanning electron microscopy (SEM) were performed. Results showed that γ-irradiation affects rice functional and nutritive characteristics proportionally with the dosage used. With 3 kGy, original digestibility values increased 37.5, 60, and 76%; gel viscosity decreased 52, 77, and 90%; and syneresis increased 0, 193, and 546% on RP2, Y, and H, respectively. Amylopectin was the starch fraction most affected as shown by SEM. Although some of these changes in cultivar attributes might be considered negative for traditional food formulations, they could help in the design of n...

Lactic Acid Fermented Products as Vehicles for Probiotics

For thousands of years microbial cultures have been used to ferment foods and prepare different kind of products. Unstable primary foodstuffs such milk, meat and vegetables can be conserved for relatively long periods of time (Table 1), maintaining their nutritious and caloric value by the use of lactic acid fermentation. Several traditional soured milks such as kefir, koumis, leben and others were used as foods and often therapeutically, before the existence of the actual knowledge on probiotics. The origins of cultured dairy products can be traced in the Bible and the sacred books of Hinduism. Metchnikoff at the beginning of the XX century proposed the beneficial effects of the lactic acid bacteria (LAB) on health and longevity.