Impact of ultrafiltration on the physicochemical properties of bovine lactoferrin: Insights into molecular mass, surface morphology, and elemental composition

Abstract

ABSTRACT: The large-scale isolation of bovine lactoferrin (bLF) typically involves using large amounts of concentrated eluents, which might introduce impurities to the final product. Sometimes, protein preconcentration is required for the greater accuracy of experimental results. In this research, the supplied bLF sample was subjected to additional UF to eliminate possible small impurities, such as salts and peptides of bLF. Beforehand, the basic characterization of native bLF, including surface charge properties and structural sensitivity to various pH conditions, was performed. The study aimed to evaluate the difference in molecular mass, primary structure, surface morphology, and elemental composition of the protein before and after UF. The research was provided by application of spectroscopic, spectrometric, electrophoretic, and microscopic techniques. Evident changes in the surface morphology of bLF were observed after UF, but the molecular masses of both proteins were comparable. According to MALDI-TOF/MS results, UF had a positive effect on bLF sample representation, improving the identification parameters, such as sequence coverage and intensity coverage.

Keywords

• bovine lactoferrin
• ultrafiltration
• SDS-PAGE
• MALDI-TOF/MS