Algae. 2009; 24(2): 121-127.
Red and Blue Photons Can Enhance the Production of Astaxanthin from Haematococcus pluvialis
Z-Hun Kim, Ho-Sang Lee and Choul-Gyun Lee*
Institute of Industrial Biotechnology, Department of Biological Engineering, Inha University, Incheon 402-751, Korea
The unicellular green alga, Haematococcus pluvialis, accumulates the highest level of astaxanthin among known astaxanthin-producing organisms. Light is the most important factor to induce astaxanthin by H. pluvialis. Blue and red LEDs, whose λmax’s are 470 and 665 nm, respectively, were used for internally illuminated light sources. Fluorescent lamps were also used for both internal and external illumination sources. The astaxanthin levels in these various lighting systems were analyzed and compared each other. The cultures under internally illuminated LEDs accumulated 20% more astaxanthin than those under fluorescent lamp. Furthermore, LEDs generated much less heat than the fluorescent lamps, which gives one more reason for the LEDs being a suitable internal light source for astaxanthin induction. The results reported here would lead novel designs of photobioreactors with improvements of illumination methods for high level of astaxanthin production. The maximum astaxanthin concentrations as well as the astaxanthin yield per supplied photon were increased by at least 20% when blue or red LEDs were supplied.
Keywords : astaxanthin, Haematococcus pluvialis, internal illumination, light emitting diodes (LEDs), photobioreactor