Astaxanthin extraction
Astaxanthin (3,3′-dihydroxy-β,β-carotene-4,4′-dione) is a ketocarotenoid derived from β-carotene oxidation. Its structure contains both ketonic and hydroxylic functional groups, which are responsible for its exceptional antioxidant properties in free radicals scavenging and in quenching singlet oxygen [7].
The raw material used for the present study was shrimp shell wastes of deep-water pink shrimp (P. longirostris). To ensure maximum yield of carotenoid pigments this deep sea species was selected. The astaxanthin was quantified in the shrimp shell extract of P. longirostris in the present study at 470 nm in hexane. The purity of astaxanthin extracted from shrimp shell waste was verified by a high-pressure liquid chromatography (HPLC). Astaxanthin was eluted in the fraction between 10.0% and 35.0% acetonitrile as a single peak (474 nm) and identified on the basis of retention time in comparison with that of standard astaxanthin.