Accumulation of Astaxanthin in Haematococcus Lacustris (Chlorophyta)¹

In N‐limited continuous chemostat cultures of the green alga Haematococcus lacustris (Gir.) Rostaf. (UTEX 16), the steady‐state astaxanthin content of the cells was determined by the specific growth rate of the cultures. The highest, pigment content was obtained at the lowest dilution rate. The specific rate of astaxanthin accumulation was, however, a function of the photon flux density measured at the illuminated culture surface. In nongrowing Haematococcus cultures, the specific rate of astaxanthin accumulation was determined by the growth rate of the culture during growth phase. The highest possible cellular astaxanthin content of all cultures was comparable and independent of the culture parameters.