Investigations Of Control Of Harmful Organisms And Metabolites Of Dunaliella Salina Teod.

Dunaliella salina Teod. (Chlorophyceae) is widely distributed in oceans and salt-water lakes all over the world. It has unique economic value in food, health care, pharmaceutical, chemical, and aquaculture industries. In this paper, the control of harmful organisms in cultivation of D. salina, effects of different nutrient concentrations and light-dark cycles on the growth and accumulation of metabolites of D. salina, and variations of accumulation of metabolites of D. salina after spaceflight were investigated. The results are summarized as follows:1. The tests of the extract from Artemisia annua L. toxicity on D. salina and ciliates were performed. The results showed that the concentration of alcohol extract was 400mg/L, which could kill ciliates effectively in nutrient solution, however, its toxicity was little on the D. salina,and that the concentration of aqueous extract was 221mg/L, which could promote the growth of D. salina and increase the contentβ-carotene and exopolysaccharides.2. This paper dealt with the study on culture of spaceflight and non-spaceflight D. salina by finding optimal combination in the concentration of four essential inorganic minerals CaCl2, MgCl2, KNO3 and KH2PO4. The optimal combination of the four inorganic minerals for the growth and accumulation of exopolysaccharides of spaceflight and non-spaceflight were assayed by single factorial experiment. It showed that the optimal combination in concentration of nutrients for the growth of spaceflight and non-spaceflight D. salina was different, because of the complex effects of several space environmental factors. The optimal combination for the growth of non-spaceflight and spaceflight D. salina were CaCl2 200 mg/L, MgCl2 500 mg/L,KNO3 1000 mg/L,KH2PO4 55 mg/L and CaCl2 250 mg/L,MgCl2 500 mg/L,KNO3 1000 mg/L,KH2PO4 15 mg/L, respectively. The optimal combination for accumulation of exopolysacchrides of spaceflight and...