Comparative Viability of Spray Dried Lactobacilli Affected by Different Protective Agents and Storage Conditions

Because of their health benefits, probiotics are a significant part of the functional food industry. Spray drying is reported as the most common method used in the food industry to encapsulate probiotics. The objectives of this study were to investigate the effects of protective agents on the viability of lactobacilli after spray drying and during storage at different conditions and to evaluate spray drying conditions to produce these probiotic powders. Lactobacillus plantarum NRRL B-4496 (LP) and Lactobacillus acidophilus NRRL B-4495 (LA) were separately grown (~109 CFU/ml) and suspended in a 200 g/L solution of high maize starch (HM); maltodextrin (MD); or gum arabic (GA). The solutions were separately spray dried at 140 °C to obtain LP and LA-powders: LPHM, LPMD, LPGA, LAHM, LAMD, and LAGA. The powders were separately placed in aluminum bags and separately packed under 97% and 10% vacuum. The powders were stored at refrigerated (4 °C) or at room (23 °C) temperature for 60 days. Physicochemical properties, energy and mass balances, and cell viability during storage were determined. Triplicate experiments were conducted and data were statistically analyzed (α=0.05). The actual production rate of powders ranged from 0.091 to 0.105 (kg dry solids/h). The energy used during spray drying was not significantly different for any of the powders. After 60 days, LPHM powders packed under 10% and 97% vacuum and stored at 4 °C had significantly higher cell viability than the other powder samples. The study demonstrated significantly improved on the viability of LP at 10% vacuum stored at refrigerated temperature for the HM treatment compared to those treated with MD and GA. The data obtained showed that high maize starch can be used as a protective agent to maintain the viability of L. plantarum powder at recommended levels for up to 60 days of storage

Hyperthermia-Triggered Doxorubicin Release from Polymer-Coated Magnetic Nanorods

In this paper, it is proposed that polymer-coated magnetic nanorods (MNRs) can be used with the advantage of a double objective: first, to serve as magnetic hyperthermia agents, and second, to be used as magnetic vehicles for the antitumor drug doxorubicin (DOX). Two di erent synthetic methodologies (hydrothermal and co-precipitation) were used to obtain MNRs of maghemite and magnetite. They were coated with poly(ethyleneimine) and poly(sodium 4-styrenesulfonate), and loaded with DOX, using the Layer-by-Layer technique. Evidence of the polymer coating and the drug loading was justified by ATR-FTIR and electrophoretic mobility measurements, and the composition of the coated nanorods was obtained by a thermogravimetric analysis. The nanorods were tested as magnetic hyperthermia agents, and it was found that they provided sufficiently large heating rates to be used as adjuvant therapy against solid tumors. DOX loading and release were determined by UV-visible spectroscopy, and it was found that up to 50% of the loaded drug was released in about 5 h, although the rate of release could be regulated by simultaneous application of hyperthermia, which acts as a sort of external release-trigger. Shape control offers another physical property of the particles as candidates to interact with tumor cells, and particles that are not too elongated can easily find their way through the cell membrane.This research work is supported by Junta de Andalucía (PE2012-FQM694); Feder Funds UE; and MINECO Ramón y Cajal programme (RYC-2014-16901)

Descripción de la satisfacción de los usuarios externos y análisis del clima organizacional del Centro de Salud Adelina Ortega, Pantasma. I Semestre 2004

Describe el nivel de satisfacción referido por los usuarios que acuden a demandar dichos servicios y analiza las percepciones del personal que labora en los ambientes de atención directa del centro de salud de Pantasma. El estudio revela un 79% de usuarios satisfechos con la atención recibida y una calificación general de la atención considerada como buena a excelente en un 82%. Sin embargo el nivel de satisfacción referido no alcanza los estándares normativos del MINSA que establece un mínimo de 95% de satisfacción considerado como adecuado El grupo etario predominante en la demanda fue de 20 a 39 años, sexo femenino y el principal motivo de consulta fue morbilidad, coincidiendo con el comportamiento general de la población nicaragüense

Dimensionado en compresión en acero: el "peso" del pandeo

La comprobación de la capacidad resistente de piezas comprimidas esbeltas es un problema bien codificado. Sin embargo la no linealidad del proceso de proyecto, sumada a la no linealidad del problema físico, exige un proceso iterativo para la definición de la pieza necesaria para resolver un problema dado. En este trabajo se demuestra la existencia de una relación de identidad entre problemas aparentemente diferentes, en base a la cual se desarrolla un enfoque teórico y un procedimiento sencillo que permite determinar, sin necesidad de iteración y sin apenas margen de error, la pieza necesaria para un problema dado. Se aporta un modelo estadístico que permite comprobar que el procedimiento aportado resulta seguro y eficiente en el 98 % de los problemas de edificación más habituales –pilares y barras de cerchas– El enfoque aportado permite por ello agilizar enormemente la toma de decisiones en este ámbito

Synthesis of Nano-structured materials for storing hydrogen as an alternative source to fossil fuels derivatives.

The decline in global reserves of fossil fuels due to the increasing energy demand has caused the petrochemical industry to be interested in finding new energy sources. An alternative that should be considered is the technology based on hydrogen as it is friendly to the environment and its combustion is greenhouse