Título

Galacto-Oligosaccharides and Lactulose as Protectants Against Desiccation of Lactobacillus delbrueckii subsp. bulcaricus

Autor

Edgar León Esparza Ibarra

Nivel de Acceso

Acceso Abierto

Licencia

http://creativecommons.org/licenses/by-nc-nd/4.0

Materias

BIOLOGÍA Y QUÍMICA - (CTI) Lactobacillus delbrueckii subsp bulgaricus desiccation galacto-oligosaccharides lactulose near infrared spectroscopy multiparametric flow cytometry damage cells

Resumen o descripción

Lactobacillus delbrueckii subsp. bulgaricus CIDCA 333 was dehydrated on desiccators

containing silica gel in the presence of 20% w/w of two types of galactooligosaccharides

(GOS Biotempo and GOS Cup Oligo H-70VR ) and lactulose, until no

changes in water desorption were detected. After rehydration, bacterial growth was monitored

at 37 C by determining: (a) the absorbance at 600 nm and (b) the near infrared

spectra (NIR). Principal component analysis (PCA) was then performed on the NIR spectra

of samples dehydrated in all conditions. A multiparametric flow cytometry assay was

carried out using carboxyfluorescein diacetate and propidium iodide probes to determine

the relative composition of damaged, viable, and dead bacteria throughout the growth

kinetics. The absorbance at 600 nm and the position of the second derivative band at

1370 nm were plotted against the time of incubation. The efficiency of the protectants

was GOS Biotempo>GOS Cup Oligo H-70VR >lactulose. The better protectant capacity

of GOS Biotempo was explained on the basis of the lower contribution of damaged cells

immediately after rehydration (t50). PCA showed three groups along PC1, corresponding

to the lag, exponential and stationary phases of growth, which explained 99% of the

total variance. Along PC2, two groups were observed, corresponding to damaged or viable

cells. The results obtained support the use of NIR to monitor the recovery of desiccated

microorganisms in real time and without the need of chemical reagents. The use

of GOS and lactulose as protectants in dehydration/rehydration processes was also supported.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Fecha de publicación

2014

Tipo de publicación

Artículo

Recurso de información

http://hdl.handle.net/20.500.11845/570

1520-6033

Formato

application/pdf

Idioma

Inglés

Audiencia

Público en general

Repositorio Orígen

Repositorio Institucional Caxcán

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