Marigold is one of the richest natural sources of carotenoids,
of which lutein esters are identified as the principal
components. Its flowers are the richest common source
of xanthophylls, ranging from 0.6 to 2.5% on a dry basis,
and 88–92% of the total xanthophylls in marigold flowers
are lutein and zeaxanthin [14,15]. In Central America several
varieties of marigold are cultivated for the purpose
of carotenoid extraction. However, the defatted marigold
residue was discarded or just used as feed or manure. In
this paper the defatted marigold residue was extracted
with aqueous-EtOH, and then the total phenolics and flavonoids
in thecrude marigold extracts were analyzed. The
ABTS, DPPH radical scavenging and FRAP assays were applied
for the evaluation of the antioxidant activity of the extracts.
The antioxidant constituents were identified by using
on-line HPLC–ABTS•+ post-column assay coupled with the
HPLC–DAD–MS method.