The effect of various wavelengths on natural astaxanthin production in the green unicellular alga Haematococcus pluvialis

초록

Haematococcus pluvialis accumulates astaxanthin (3,3’-dihydroxy-β,β’-carotene-4,4’-dione) in the cell cytoplasm. Astaxanthin, a red ketocarotenoid, is receiving commercial interests due to its use as a preferred pigment in the feeds of farmed fish, vitamin precursors, antiaging reagents, anticancer agents and immunomodulators. The world market of animal feed alone is projected over 450 million dollars in 2000. The H. pluvialis were cultured at 20oC under fluorescent light (FL) with supplements of various wavelengths from LEDs (680, 605, 580, 570, 555 and 470 nm). Despite the light intensities from LEDs were less than 5% of the light intensity from FL, the ef-fects of supplemental light found to be dramatic. The growth in the cultures with 470, 555, 570, and 580 nm seemed to be inhibited by the supplemental wavelengths, while the growth with 680 and 605 nm was comparable to that without supplements (control). However, the supplement of shorter wavelengths (470 and 555 nm) induces carotenoid production at earlier stage of the culture. The amount of carotenoid accumulation was proportional to the total cell volume. This result suggested that supplementing proper wavelength in two-stage culture could optimize as-taxanthin production by H. pluvialis.