Carotenoids and their fatty-acid esters in banana peel.

In relation to banana ripening, banana peel was examined for carotenoid pigments by a combination of alumina column chromatography and high-performance liquid chromatography (HPLC). Carotenoids and their fatty-acid esters were first separated by an alumina column into five fractions, of which each was further subfractionated by HPLC with different kinds of solvent. The carotenoid content of the banana peel was in the range of 3-4 micrograms per gram as lutein equivalent. The ingredients of the carotenoids were ascertained to consist of lutein, beta-carotene, alpha-carotene, violaxanthin, auroxanthin, neoxanthin, isolutein, beta-cryptoxanthin and alpha-cryptoxanthin. Most of the oxygenated carotenoids were found to occur in the esterified form, mainly with myristate, and to a lesser extent with laurate, palmitate or caprate.