Zeaxanthin Dipalmitate-Enriched Emulsion Stabilized with Whey Protein Isolate-Gum Arabic Maillard Conjugate Improves Gut Microbiota and Inflammation of Colitis Mice

Abstract

In the present study, protein-polysaccharide Maillard conjugates were used as novel emulsifiers and bioactive carriers. Effects and potential mechanisms of zeaxanthin dipalmitate (ZD)-enriched emulsion stabilized with whey protein isolate (WPI)-gum Arabic (GA) conjugate (WPI-GA-ZD) and ZD-free emulsion (WPI-GA) on gut microbiota and inflammation were investigated using a model of dextran sulfate sodium (DSS)-induced colitis in mice. As a result, supplementation with WPI-GA and WPI-GA-ZD improved the serum physiological and biochemical indicators, decreased the expression of pro-inflammatory cytokines and related mRNA, as well as increased the tight junction proteins to a certain extent. 16S rDNA sequencing analyses showed that supplementation with WPI-GA and WPI-GA-ZD presented differential modulation of gut microbiota and played regulatory roles in different metabolic pathways to promote health. Compared with WPI-GA, the relative abundances of Akkermansia, Lactobacillus and Clostridium_IV genera were enriched by the intervention of WPI-GA-ZD. Overall, the designed carotenoid-enriched emulsion stabilized with protein-polysaccharide conjugates showed potential roles in promoting health.

Behavior of protein-polysaccharide conjugate-stabilized food emulsions under various destabilization conditions

“…The highest β-carotene protection in the ternary conjugate-coated oil droplets of O/W emulsions has been attributed to (i) the presence of functional groups in the conjugate that function as radical-scavenging agents, (ii) the ability of the protein moiety of the conjugate (e.g., lactoferrin) to chelate pro-oxidant transition metals, and (iii) the potential of the ternary conjugate in the formation of thick and dense interfacial films on the droplet surfaces, inhibiting pro-oxidants from interacting with the lipids physically ( Liu et al, 2016 ). It could be also noteworthy that the protein-polysaccharide conjugates can successfully encapsulate bioactive materials such as fish oil, conjugated linoleic acid, and nutraceuticals ( Chen et al, 2022 , Huang et al, 2020 , Jia et al, 2020 , Kan et al, 2022 , Li et al, 2017 , Nooshkam and Varidi, 2021a ). In this regard, the conjugates could act as antioxidants and increase the wall integrity of the microcapsules, retarding the penetration of oxygen into the microcapsules and improving the chemical and storage stability of the bioactive compound.…”