Introduction
Zeaxanthin (C40H56O2) is the principal pigment obtained from
yellow corn or from the marigold flower; it is involved in many
important physiological functions of the human body. Dietary
xanthophylls such as lutein and zeaxanthin play important roles
against age-related macular degeneration (AMD) and other agerelated
eye disease (AED) [1–3]. Lutein and zeaxanthin have been
found to accumulate in high concentrations within the human
retina [4]. Photo-protective mechanisms are important to prevent
harmful reactions in plants (marigold) and algae (Nannochloropsis
oculata). Harmful reactions are induced by an excess of photons
absorbed from sunlight irradiation. Carotenoids have been suggested
as key molecules in these photo-protective mechanisms. For
example, beta-carotene can act as an effective quencher of singlet
oxygen in the photo-system II reaction center [5]. Another exam