Iron-rich chitosan-pectin colloidal microparticles laden with ora-pro-nobis (Pereskia aculeata Miller) extract

Abstract

Iron deficiency represents a global nutrition gap that calls for innovative strategies including food fortification, while overcoming the drawbacks of taste and reactivity of iron. The aim of this work was to develop iron-rich colloidal microparticles laden with a Brazilian plant food extract from ora-pro-nobis (OPN, Pereskia aculeata Miller). We formulated electrostatic self-assembled complexes of oppositely charged chitosans and pectin laden with aqueous OPN extract. After characterisation of the physical properties, selected formulations were examined in their colloidal stability (50 mM NaCl, Dulbecco's modified eagle medium (DMEM), simulated gastric fluid (SGF) and simulated intestinal fluid (SIF)), production yield, iron association efficiency, transmission electron microscopy (TEM), cellular cytotoxicity and iron uptake using Caco-2 cells. The ζ-potential varied from ~ −25 mV to ~ +23 mV regardless of the degree of acetylation (DA) of chitosan. The production yield ranged between 20 and 26%. The particles were stable at DMEM, SGF and SIF during 3 h. Iron association efficiency was ~60% for systems charge ratio (n+/n–) = 5.00. TEM analyses revealed invariably spherical morphology. OPN-laden microparticles did not present cytotoxicity against Caco-2 cells. Higher cellular ferritin levels were determined for the particles comprising OPN extract and n+/n– = 5.00. We obtained in vitro proof of concept of the efficiency of chitosan/pectin particles to delivering iron from a Brazilian edible plant extract. The industrial potential of this approach as a viable alternative for iron fortification or supplementation by the food industry is yet to be realised.