PREPUBLICATION: PHOTOSTABILITY OF β-CAROTENE/MODIFIED KAOLINITE

Nelly Wahyuni (1) , Georges Zissis (2) , Zephirin Mouloungui (1)

1 CAI - Chimie Agro-Industrielle
2 LAPLACE-LM - Lumière et Matière

Abstract: β-carotene (BC), a natural organic compound, is very highly sensitive to light. The stability of BC can be improved by various methods. The aim of this study was to propose a simple method for improving the photostability of BC with modified kaolinite (MK). MK was produced by kaolin modification, through calcination and interaction with ZnCl2. The characteristics of the MK were determined by using scanning electron microscope–energy dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction (XRD), infrared spectroscopy (IR), and surface area analyzer. The photostability of BC was measured with a UV-spectrophotometer. The XRD patterns of the kaolinite showed layer disruption during calcination at 600°C, leading to metakaolinite production. Surface area analysis and IR-spectroscopy revealed an increase in mean pore volume in the MK and a shift of the signal for the –OH group, respectively. MK decreased the photodegradation of BC, and increased the half-life of this molecule by almost 15-fold than the only BC 1.44 h. The amount of BC photostabilized by MK expressed as percentage of photostability, at five hours it was 61.87%. The amount of BC adsorbed onto the kaolinite was related to the photostability of BC.

Mots clés: β-carotene; half-life; kaolin; metakaolinite; modified kaolinite; photodegradation; photostability

Domaines: Matériaux

Nelly Wahyuni, Georges Zissis, Zephirin Mouloungui. PREPUBLICATION: PHOTOSTABILITY OF β-CAROTENE/MODIFIED KAOLINITE. Clays and Clay Minerals, 2018, ⟨10.1346/CCMN.2018.064115⟩. ⟨hal-02509831⟩