Carotenoids of Therapeutic Significance from Marigold

Abstract

Use of flowers and plants for worshipping, decoration and personal adornment is an integral part of Indian cultural heritage since pre-historic times. Marigold is a potential ornamental plant grown commercially in different parts of the world and obtained from different species of Tagetes of family Asteraceae. The essential oil from Tagetes erecta flowers has been used in high class perfumery and also acts as antihaemorrhagic, anti-inflammatory, antiseptic, antispasmodic, astringent, diaphoretic and emmenagogue. The oil is very valuable in aromatherapy for its powerful skin healing effects and also possesses fly repellant properties. Marigold varieties have pesticidal value as they destroy ground pests particularly nematodes. The genus is also recognized as a potential source of very interesting biologically active products viz. carotenoids that are currently being used as food colorants, nutritional supplements and poultry feed additives and in ophthalmology for the treatment of age related ocular diseases viz. cataract and dry age related macular degeneration (ARMD). Several species of the genus Tagetes find tremendous application as per the traditional database for the treatment of various ailments and diseases. Carotenoids from Tagetes species The extracts of Tagetes erecta were earlier reported to contain epoxides such as lutein 5, 6-epoxide and other oxidation products of lutein. Some preliminary studies during the same phase demonstrated the predominance of lutein and zeaxanthin (88-92%) out of 17 different separated pigments, while less than 3% were reported to be epoxy pigments [1]. The carotenoid composition of marigold extract product was analyzed later via HPLC whereby epoxides namely violaxanthin and neoxanthin were it should be reported [2]. The saponified Tagetes erecta flower extract was reported for 93% utilizable pigments (detected at 450 nm), consisting of all trans and cis-isomers of zeaxanthin (5%), all trans and cis-isomers of lutein, and lutein esters (88%). Among the lutein isomers, trans-lutein was reported as the major component with several cis-lutein isomers as minor components from the commercial marigold flower extract. The yield of xanthophyll content in well preserved flowers of Tagetes erecta was reported to be 105.19 g/kg in contrast to the unpreserved flower sample (58.87 g/kg), thereby emphasizing the significance of flower preservation during the extraction of xanthophylls (Figures 1 and 2) [3]. Purification of carotenoids