Enhancement and determination of astaxanthin accumulation in green alga Haematococcus pluvialis

This chapter discusses the enhancement and determination of astaxanthin accumulation in green alga—Haematococcus pluvialis. Astaxanthin is also found in algae, such as Chlamydomonas nivalis and Haematococcus pluvialis, Euglena rubida, and Acetabularia mediterranea. There has been a growing interest in the use of this pigment as a colorant for egg yolk in the poultry industry and in aquaculture, where it is used as a feed supplement in the production of salmon and shrimp. In addition, the carotenoids are lipophilic oxygen quenchers with potential anticancer activities, and it has been shown that this carotenoid possesses a higher antioxidant activity than β-carotene. Research has been done on the conditions favoring accumulation of this ketocarotenoid by the unicellular alga H. pluvialis. It has been suggested that nitrogen deficiency and high light intensity cause massive accumulation of this red pigment in H. pluvialis. Other hypotheses concerning astaxanthin production in H. pluvialis argue either that it is favored by agents that prevent cell division without impairing the ability of the alga to assimilate carbon or the carbon–nitrogen balance in the medium determines the degree of carotene formation. This chapter defines the conditions favoring astaxanthin accumulation in H. pluvialis.