Lycopene: Heterogeneous Catalytic E/Z Isomerization and In Vitro Bioaccessibility Assessment Using a Diffusion Model

Abstract

Highly efficient heterogeneous catalytic E/Z isomerization of lycopene was achieved using an iodine-doped titanium dioxide (I-TiO ) catalyst prepared by sol-gel method. The effects of reaction temperature and reaction time were investigated in detail. The maximum total Z-ratio of lycopene exceeded 78% after 2 h of refluxing at 75 °C in ethyl acetate. Moreover, lycopene samples with a series of total Z-ratios were prepared and the bioaccessibility of these samples was estimated using a diffusion model, the results showed that the bioaccessibility of lycopene markedly increased conforming to a linear regression model with increasing of the total Z-ratio of lycopene from 3.6% to 78.5%. Furthermore, the specific role of the microstructure and melting point of 3.6% and 78.5% total Z-ratio of lycopene was also investigated to understand the probable mechanism for the enhanced bioaccessbility of (Z)-lycopenes.

LC‐MS/MS for simultaneous detection and quantification of Amadori compounds in tomato products and dry foods and factors affecting the formation and antioxidant activities

“…The content of lycopene was measured by HPLC using all‐ e ‐lycopene as standard according to our previous report (Sun, Yang, Li, Raza, & Zhang, ). Tomato powder (5.0 g) was extracted by 30 mL ethyl acetate under ultrasound for 20 min.…”

Enhanced Lycopene Extraction from Gac (Momordica cochinchinensis Spreng.) by the Z‐Isomerization Induced with Microwave Irradiation Pre‐Treatment

“…Therefore, it is thought that the regular arrangement of carotenoid molecules is prevented by the coexistence of the Z ‐isomers, resulting in the change in physical properties. Moreover, catalytically Z ‐isomerized lycopene may be less prone to crystallization, and an oily aggregate state has been proposed for lycopene Z ‐isomers found in the globular chromoplasts of tangerine tomatoes . Furthermore, (13 Z )‐ and (9 Z )‐lycopene likely have enormous steric hindrance, as their Z ‐configured bond is located near the center of the conjugated chain, leading to their high solubility (Figure C), and strongly support this suggestion.…”

Chemical‐Free Approach for Z‐Isomerization of Lycopene in Tomato Powder: Hot Air and Superheated Steam Heating above the Melting Point of Lycopene

“…On heating at 250 °C, the total Z ‐isomer content reached ≈80% within a short time (5 min) in both the heating methods. Several studies also obtained ≈80% Z ‐isomer in lycopene; however, these studies used toxic organic solvents and catalysts and required considerable time to obtain such high amount of the Z ‐isomers . When tomato powder was heated above 240 °C, lycopene in tomato powder was decomposed in both the heating methods (Figure 3b).…”