Kinetic study on photostability of retinyl palmitate entrapped in policosanol oleogels. (30th July 2018)

• Record Type: Journal Article
• Authors: Tian, Yixing; Acevedo, Nuria C.
• Is Part Of: Food chemistry. Volume 255(2018)
• Page Start: 252
• Page End: 259
• Publication Date: 2018-07-30
• Subjects: Oleogel -- Policosanol -- Retinyl palmitate -- Photostability; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2018.02.025
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Policosanol oleogels improved the photostability of RP. Policosanol oleogels blocked energy absorption from UVA to protect RP. Photodegradation of RP followed a 2nd order reaction. From the reaction kinetics, it would be possible to predict the RP photodegradation rate. Abstract: Photostability of all- trans retinyl palmitate (RP) (100% bioactivity) was studied in policosanol oleogels (PCOs) (7–12% w/w policosanol in soybean oil) after UVA irradiation. RP was incorporated into PCOs at levels of 0.04%, 0.1% and 1% (w/w). PCOs efficiently protected RP from UVA-mediated degradation. Over 75% RP-activity remained in PCOs after 4 days of UVA irradiation, while 12% RP-activity remained in soybean oil. HPLC analysis showed that cis -RP was formed in liquid soybean oil after 2 days of UVA irradiation while it was absent in PCOs matrices. PCOs blocked the energy absorption from UVA and further dampened the UVA-mediated ionic photodissociation and free radical reaction due to matrix immobilization. For all samples, RP photodegradation followed a 2nd order reaction. From the reaction kinetics, it would be possible to predict the RP photodegradation rate in PCO matrices. PCOs were shown to be a promising matrix to protect RP from photodegradation.