The Impact of Extraneous Salicylic Acid (SA) to Astaxanthin Accumulation of Haematoccus pluvialis

Effect of extraneous 2,4-D on astaxanthin accumulation in H. pluvialis was studied in this paper. After different concentration grades of 2,4-D were added into the vegetative green cells respectively, then H. pluvialis were cultivated under unfavorable growth conditions (24 h light cycle, 5000 Lx, 25°C, nutrition de- ficiency) to promote astaxanthin accumulation. In this stage, morphological changes of cells treated by dif- ferent grades of 2,4-D concentration were observed with optical microscopy. Moreover, astaxanthin content was determined with absorption spectral (OD490). Results showed that astaxanthin accumulation might be promoted at 20 mg/L 2,4-D treatment which could quicken astaxanthin accumulation 15 days compared with blank controls. Moreover, the increasing production extents of astaxanthin reached 13.4% than blank con- trols.