Physicochemical and functional comparison of food-grade and precision-fermented bovine lactoferrin

This study provided a comprehensive physiochemical and functional comparison between food-grade, commercially available bovine lactoferrin (cLF) and two precision-fermented variants (pfLF_highFe and pfLF_lowFe) at varying iron saturation levels. LC-MS and FTIR/CD spectroscopy confirmed high purity and structural fidelity at primary and secondary levels, while UV-vis analysis revealed comparable molar absorptivity across all preparations. Fluorescence spectroscopy demonstrated tertiary structural variability with redshifts observed as a result of iron binding. Molecular weight (M _w ) comparisons made using SDS-PAGE showed pfLF_highFe and pfLF_lowFe closely resembled cLF, while glycosylation analysis demonstrated very similar N-glycan compositions and site occupancy across low iron samples. The isoelectric points (pI) of pfLF_highFe and pfLF_lowFe were similar to cLF; however, varied slightly as a function of iron saturation, as did surface hydrophobicity (S ₀ ) measurements. Thermal denaturation analyses revealed characteristic behaviour of bovine lactoferrin preparations, with differences again observed according to the preparation’s iron saturation. Functional studies highlighted the iron chelating ability of native-LF preparations, cLF and pfLF_lowFe, and accompanying antimicrobial activity, but comparable interaction capacity with Lipid A (LPS) demonstrates preservation of structural and certain functional capabilities in precision-fermented bovine lactoferrin irrespective of iron saturation levels.