Characterization of a multilayer film activated with Lactobacillus curvatus CRL705 bacteriocins.

Background: Bacteriocins produced by lactic acid bacteria offer enormous promise for food safety preservation. In this study an active multilayer film obtained by the incorporation of lactocin 705 and lactocin AL705, two bacteriocins produced by Lactobacillus curvatus CRL705 with antimicrobial activity against Lactobacillus plantarum CRL691 and Listeria innocua 7, respectively, was characterized for its potential application in active packaging technology. Film activity performance at different storage conditions, bacteriocins transfer into water and sunflower oil, and film surface properties were evaluated.

Retention of Cd, Zn and Co on hydroxyapatite filters.

This study qualifies and quantifies the immobilization of Cd, Zn and Co, (used as models of bivalent metal ions due to their relevant toxicity) in filters of synthetic hydroxyapatite (HAP) [Ca5(PO4)3OH]. They were flushed with solutions containing Cd (1 x 10(-5)M), Zn and Co (1 x 10(-4)M) at constant pH (8.6) and ionic strength (0.

Interaction of catechol and gallic acid with titanium dioxide in aqueous suspensions. 1. Equilibrium studies.

The adsorption isotherms of catechol (1,2-dihydroxybenzene) and gallic acid (3,4,5-trihydroxybenzoic acid) onto titanium dioxide (Degussa P-25) were measured at various pH values and room temperature using attenuated total reflection Fourier transform infrared (FTIR-ATR) data, processed by singular value decomposition. The affinity is largely pH independent, although the deprotonatation of the carboxylic group in gallic acid might produce a slight increase in the affinity. Catechol was shown to form two complexes, with Langmuir stability constants log K of 4.

Dissolution of Nickel Ferrite in Aqueous Solutions Containing Oxalic Acid and Ferrous Salts.

The dissolution of nickel ferrite in oxalic acid and in ferrous oxalate-oxalic acid aqueous solution was studied. Nickel ferrite was synthesized by thermal decomposition of a mixed tartrate; the particles were shown to be coated with a thin ferric oxide layer. Dissolution takes place in two stages, the first one corresponding to the dissolution of the ferric oxide outer layer and the second one being the dissolution of Ni(1.