Haematococcus pluvialis is a freshwater single cell green alga.The red cells of H. pluvialis can accumulate large amount of astaxanthin,which makes this species an ideal source for astaxanthin production. Astaxanthin is a strong colorant and it has powerful anti-oxidative ability. Therefore,it has a broad application in health products industry,food industry, cosmetic product industry and breeding industry.In the process of producting astaxanthin by H. pluvialis, the screening of excellent strains and clari...