LACTOFERRIN ADSORBED ONTO BIOMIMETIC HYDROXYAPATITE: A MULTIFUNCTIONAL ANTIMICROBIAL MOLECULE

Lactoferrin (LF), is an iron-binding protein, belonging to transferrin family. It is found in the mucosal secretions (tears, saliva, milk, and colostrums) of the majority of mammalian species, including humans. LF is a multitask molecule: it partecipates to iron absorption and distribution, but also displays anti-inflammatory, antioxidant, anticarcinogenic, and antimicrobial properties. Hydroxyapatite (HA) plays an important role in the formation of the bony skeleton and bone remodeling. Alteration of HA metabolism can cause serious clinical consequences, such as arterial calcification, chronic kidney disease or osteoporosis. HA is also used in numerous bioengineering and biomedical applications - due to its bioactivity and osteoconductivity – and also as vehicle for drug targeting, bone scaffolds and implant coating materials, filler in polymeric matrices. In this project, the biological properties (such as antimicrobial, immunomodulatory and antioxidant activities) of lactoferrin adsorbed onto biomimetic hydroxyapatatite nanocrystals (LF-HA) were evaluated. After the biological characterization, the complex was embedded in an active packaging system (on a cling film) - by electrodeposition - to estimate the antioxidant property of this active packaging system. Packaging protects food from external pathogen contamination and environmental factors (oxygen, moisture and heat), providing longer product shelf life and avoiding the quality decay. Shelf life prolongation is possible by controlling enzymatic and microbial activities through the control of temperature, addition of salt, or by removing oxygen. In recent years, foods preserved with natural additives have become very popular due to the great consumer awareness and concern regarding synthetic chemical additives. The tests carried out showed the antimicrobial and antioxidant efficacy of LF-HA versus the lactoferrin alone, when tested at the same concentrations, and the effectiveness of this molecule embedded in a food packaging system. The results obtained permit to conclude that the chemical manipulation of the lactoferrin significantly improved the antimicrobial and antioxidant activities of the native molecule. The main characteristics of the food packaging system obtained by electrodeposition of LF-HA on cling film are: uniform coating with LF-HA obtained throughout a new method of electrodeposition; long lasting stability, when stored for six months or longer at room temperature before being used to protect the food; stable to deep freezing, for six months or more