Studies on Citrus Carotenoids

Part I. Systematic separation of carotenoid groups by thin layer chromatography

Abstract

The systematic separation of carotenoid groups depended on hydroxy gr. and epoxide gr. by TLC has been studied.
Saponified orange (Unshiu) peel pigment mixture was developed on an aluminium oxideKieselgur (1:1) with pet. ether-acetone-methanol (110:5:2) and separated into nine groups. These carotenoid groups were identified by absorption spectrum, furanoxide formation and HCl coloring test as hydrocarbon, monol, monol monoepoxide, diol, diol monoepoxide I, diol diepoxide I, diol monoepoxide II, diol diepoxide II and polyol.
By means of TLC method the adequate sample applied on the plate (20×20cm) was about 0.1mg of total carotenoid and the average recovery was estimated as 95%. All procedure of TLC method from spotting to OD measurement was taken 45-50 minutes.
Large quantative separation of carotenoids mixture was carried out by partition chromatography on a silica gel colum (2×5cm) and obtained five fractions less than three hours procedure. The components of these fractions were identified as I: hydrocarbon, II: monol+monol monoepoxide, III: diol, IV: diol monoepoxide+diol diepoxide and V: polyol. The adequate samples applied on this column were 0.25-0.5mg of total carotenoid and the recovery was estimated as 95.5%.