Water soluble pentosans (WSP) from doughs and breads made with different enzyme preparations are characterized according to extraction yield, sugar composition, xylose/arabinose ratio and molecular weight (MW) distribution. Extraction yield was greater for dough than for bread samples, ranging from 0.94 to 1.64%, but bread extracts had a higher purity. Percent of pentoses in purified WSP was greater in pentosanase supplemented samples (28-55%) than in control and amylase containing samples (23-32%). Major sugars were xylose and arabinose, but glucose and mannose also appeared in the extracts. The xylose/arabinose (Xyl/Ara) ratio was 1.3-1.6 and underwent small changes during processing. Enzyme addition caused an increase in Xyl/Ara ratio, attributable to a debranching of arabinoxylans (AX) with higher degree of Ara substitution by arabinofuranosidase. Addition of pentosanases had a significant effect in increasing WSP with MW over 39 000, whereas those of low MW changed only slightly. MW distribution depended on enzyme source, and whereas some enzymes showed activity during fermentation others increased their activity during baking. No synergistic effects were observed in studied variables due to the combination of amylases with pentosanases. Protein in WSP extracts eluted together with ferulic acid suggesting they were linked, but not associated with a determined carbohydrate fraction.

Conventional water treatments of disinfection have used chlorine and its derivatives to eliminate pathogenic microorganisms; however, their use generate toxic products. Pollution produced by industrialization and the growing resistance of bacteria to antibiotics have led to the search for new treatments that ensure the good physicochemical and microbiological quality of water, the elimination of emerging pollutants and to avoid by-products formation. This review compares the conventional disinfection treatments using chlorine and peracetic acid, and advanced one, among which the simultaneous disinfection using UV/Cl stand out as an alternative for wastewater treatment. The last one ensures a better quality of water, high efficiency, short process times, and low costs. | Los tratamientos convencionales de desinfección del agua han utilizado al cloro y sus derivados para la eliminación de microorganismos patógenos; sin embargo, su uso genera productos tóxicos. La contaminación producida por la industrialización y la creciente resistencia de las bacterias a antibióticos han llevado a la búsqueda de nuevos tratamientos que aseguren la buena calidad fisicoquímica y microbiológica del agua, la eliminación de contaminantes emergentes y que eviten la formación de subproductos. En la presente revisión se muestra una comparación de los tratamientos convencionales de desinfección con cloro y ácido peracético, y los avanzados, entre los cuales destaca la desinfección simultánea de UV/Cl, como alternativa para el tratamiento de aguas residuales. Este último permite asegurar una mejor calidad del recurso, alta eficiencia, tiempos reducidos y costos bajos.