Studies in carotenogenesis. 11. Carotenoid synthesis in the alga Haematococcus pluvialis

Abstract

Green cultures of H. pluvialis contain beta-carotene, lutein and small amounts of a 3rd pigment, possibly violaxanthin. Traces of 2 other pigments were observed but no colorless polyenes could be detected. Lutein represents about 75-80% and beta-carotene 10-20% of the total carotenoids. The change in cells of H. pluvialis from green to brown or red is accompanied by the formation of considerable amounts of astaxanthin. This synthesis is not at the expense of the pigments already present in the green stage. Relatively more astaxanthin is formed on a soil extract medium than on a nitrate: acetate medium. Light is necessary for the formation of astaxanthin. Diphenylamine completely inhibits growth of H. pluvialis at a concentration of 1/560,000.