THE EFFECTS OF MELATONIN ON THE PHYSIOLOGICAL INDEX AND THE ACCUMULATION OF ASTAXANTHIN IN HAEMATOCOCCUS PLUVIALIS

In this study,the effects of different concentrations of melatonin(MLT) on the growth,astaxanthin content,physiological indexes and gene expression of Haematococcus pluvialis LUGU were investigated.Results showed that the astaxanthin content significantly increased in algal cells at 10μmol/L MLT,the maximum astaxanthin content was 31.32 mg/g,and enhanced by 2.36 times compared with that of the control.The carbohydrate and protein contents increased by 1.36 and 1.37 fold,respectively.Furthermore,the expression levels of the astaxanthin synthesis genes pds and bkt improved by 5.79 and 12.16 times,respectively.These results indicated that MLT could significantly enhance astaxanthin accumulation in H.pluvialis.This study proposed a strategy to efficiently produce astaxanthin by using microalgae.