Extraction, Identification and Photo-Physical Characterization of Persimmon (Diospyros kaki L.) Carotenoids.

Fiche publication


Date publication

janvier 2017

Journal

Foods (Basel, Switzerland)

Auteurs

Membres identifiés du Cancéropôle Est :
Dr FROCHOT Céline, Dr VANDERESSE Régis


Tous les auteurs :
Zaghdoudi K, Ngomo O, Vanderesse R, Arnoux P, Myrzakhmetov B, Frochot C, Guiavarc'h Y

Résumé

Carotenoid pigments were extracted and purified from persimmon fruits using accelerated solvent extraction (ASE). Eleven pigments were isolated and five of them were clearly identified as all-trans-violaxanthine, all-trans-lutein, all-trans-zeaxanthin all-trans-cryptoxanthin and all-trans-β-carotene. Absorption and fluorescence spectra were recorded. To evaluate the potential of ¹O₂ quenching of the purified carotenoids, we used a monocarboxylic porphyrin (P1COOH) as the photosensitizer to produce ¹O₂. The rate constants of singlet oxygen quenching (Kq) were determined by monitoring the near-infrared (1270 nm) luminescence of ¹O₂ produced by photosensitizer excitation. The lifetime of singlet oxygen was measured in the presence of increasing concentrations of carotenoids in hexane. Recorded Kq values show that all-trans-β-cryptoxanthin, all-trans-β-carotene, all-trans-lycopene and all-trans-zeaxanthin quench singlet oxygen in hexane efficiently (associated Kq values of 1.6 × 10⁸, 1.3 × 10⁸, 1.1 × 10⁸ and 1.1 × 10⁸ M(-1)·s(-1), respectively). The efficiency of singlet oxygen quenching of β-cryptoxanthin can thus change the consideration that β-carotene and lycopene are the most efficient singlet oxygen quenchers acting as catalysts for deactivation of the harmful ¹O₂.

Référence

Foods. 2017 Jan;6(1):