Interactions of lycopene with β-cyclodextrins: Raman spectroscopy and theoretical investigation

Abstract

Carotenoids (Cars) are essential molecules with diverse biological roles, and their solubility can be enhanced by forming complexes with cyclodextrins, which incorporate them into their cavities without chemical bonds. In this study, we investigated the interactions of lycopene with β-cyclodextrins using Raman spectroscopy, molecular dynamics and DFT. We simulated models of simplified structures, including various β-cyclodextrins and trans and cis lycopene configurations, to better understand how structural changes influence the v₁ band shift observed in Raman spectroscopy. Our focus was on reducing interactions such as van der Waals interactions, hydrogen bonds, and electrostatic effects to isolate the impact of structural alterations on the methyl group in carotenoids. We measured solid lycopene and its complexes with β-cyclodextrins, which exhibited Raman v₁ shifts. According to the modelling data, this can be attributed to the monomer band of lycopene.