Spontaneous interactions between α-lactalbumin and native or heat-denatured lactoferrin

Abstract

At pH 5.0 to 7.0, native lactoferrin weakly interacts with α-lactalbumin at certain mixing ratios. For denatured lactoferrin and native α-lactalbumin a higher turbidity is observed over a wide mixing ratio. The zeta potential is negative at high α-lactalbumin/lactoferrin ratios and positive at high lactoferrin/α-lactalbumin ratios, with a zero zeta potential at a certain mixing ratio the zeta potential. This isoelectric point shifted to higher lactoferrin/α-lactalbumin ratios as the pH increased. The composition of the turbid material for the unheated lactoferrin/unheated α-lactalbumin samples could not be determined; however, for the heated lactoferrin/unheated α-lactalbumin, the composition of the pelleted material indicated that not all the lactoferrin or α-lactalbumin was in the complexes, and, except for the sample at pH 5.0, the lactoferrin/α-lactalbumin ratio in the complexes was higher than that in the original samples. Further studies are required to elucidate the potential applications of the complexes formed.