Spice active ingredients affect the micellization, permeation and bioavailability of structurally different carotenoids in human intestinal epithelial Caco-2 cells

This study evaluated the influence of active spice ingredients on the bioaccessibility and bioavailability of different carotenoids at the enterocyte level. Briefly, carotenoids solubilized micellar fractions obtain by simulated digestion of spinach (β-carotene; BC and lutein; LUT) or brown seaweed (fucoxanthin; FUCO) or shrimp (astaxanthin; AST) either with or without curcumin/capsaicin/piperine. Further, physicochemical properties (particle size and viscosity) of micelles were analyzed and correlated bioaccessibility, permeability characteristics, and bioavailability of carotenoids in Caco-2 cells. The digestion of carotenoid's source with spice compound affected carotenoid solubilization/micellization, cumulative percent of particle size, and viscosity in the following order of spice compound treatments; curcumin > capsaicin > piperine > control. The carotenoids level in micelles higher in capsaicin and piperine than curcumin and control digested groups. The increased carotenoids bioaccessibility may be due to lesser hydrophobic interaction found in capsaicin and piperine than curcumin. Further, based on importance and distinct nature, BC and LUT were used bioavailability studies. The enhanced cellular uptake and secretion of carotenoids in triglycerides rich lipoproteins by capsaicin and piperine is due to changes in integrity, permeability, the fluidity of the epithelial barrier of absorption than curcumin and control groups. These findings opine the interaction of carotenoids with specific dietary component (spices) and their regulatory metabolism at the intestinal level is vital for the enteral nutrition of carotenoids.