Influence of pH in the recovery of lactoferrin from whey with ceramic membranes

A wide collection of proteins in relatively low concentrations but with an important biological activity is present in bovine whey. Among them, lactoferrin shows strong bacterial and antiviral properties, preventing the growth of pathogenic organisms in the gut, stimulating the immune system and enhancing iron absorption [1]. Lactoferrin recovery from whey is therefore of great interest since it can be used in the development of improved infant formula, functional foods and nutraceuticals. To this end, methods have been devised employing, for instance, surfactant-stabilized microbubbles [2] or ion exchage chromatography [3]. In the field of membrane technology, high performance tangential flow [4] filtration has been suggested as a feasible technique to allow the separation of lactoferrin at industrial scale [5]. In this work, the effect of pH in the selectivity of lactoferrin ultrafiltration through a ceramic membrane with respect to the major whey proteins has been studied. The results obtained are useful to design an optimal strategy to exploit the electrostatic protein–membrane interactions that takes place in this process. 2. Experimental