The Effects Of Different Sources Of Water On Growth And Quality Of Dunaliella Salina

Dunaliella salina has a lot of beta-carotene?protein?polysaccharide,and it has unique economic value at food processing?health and medical?chemical engineering and breeding industry.It can be cultured by seawater directly,however,the marine environment was polluted and it need a lot of land to be cultured.So we must look for other water to cuture Dunaliella Salina except seawater and look for other wide land.In our study,we collected five kinds of different sources of water in the two regions,including the seawater from Tianjin Central Fishing Port,the cooling water from Tianjin Beijiang Power Plant and three kinds of brine from Chaerhan salt lake of Qinghai Chaidamu basin.According to GB 17378.4-2007 to determine the basic components of five different water,including the pH?salinity and the content of mercury?arsenic?ka2+?Mg2+?Cl-?SO42-?alkalinity?total nitrogen?total phosphorus.Those different water was used to culture Dunaliella Salina,then we analysised the influence of physical signs and quality of Dunaliella Salina.In order to provide basic data to expand the culture area of Dunaliella Salina.The experimental results show that,use those different water to culture Dunaliella Salina,the maximum of growth velocity was increased 14.5?11.3?24.2?3.2?27.3 times compared with the early.After 15 days,the nitrate reductase activity was 0.671?0.606?0.714?0.082?0.734?gNO2-·g-1·h-1 respectively.After 21 days,the chlorophyll of Dunaliella Salina was 24.6?23.8?24.4?3.4?24.9 mg/L respectively,and their dry weight was 400.5?403.8?405.2?69.5?409.5 mg.Except the group of the extracting potassium brine,the net photo synthetic rate was 113.8?105.7?123.2?128.6 ?molO2·mg-1Chl·hr-1 respectively of the rest of four groups,the respiration rate was 21.9?18.6?35.7?28.2 ?molO2·mg-1Chl·hr-1 respectively.The light saturation point was 108.4?172.5?105,7?77.6?mol/(m2·s)respectively,the light compensation point was 17.2?25.2?23.5?13.0?mol/(m2·s)respectively.By using four kinds of water to culture Dunaliella Salina except the extracting potassium brine,after 30 days,determined the quality of Dunaliella Salina powder.The experimental results show that,the content of beta-carotene was 0.60%?1.15%?1.93%?1.96%respectively,the content of lead was 0.46?0.43?0.45?0.44mg/kg respectively,the content of arsenic was 0.89?0.44?0.24?0.24mg/kg respectively,the content of mercury was 0.011?0.012?0.010?0.010mg/kg respectively.The content of hexachloro-cyclohexane soprocide was less than 0.010mg/kg in Dunaliella Salina powder cultured by the cooling water from Tianjin Beijiang Power Plant.Comprehensive comparison the Dunaliella Salina which was cultured by processed brine which were diluted 10-folds has long stable phase,the chlorophyll and the dry weight have no significant difference with the group of the seawater from Tianjin Central Fishing Port.The light saturation point and the light compensation point was lower than other groups,so the Dunaliella Salina can be cultured at spring and autumn,prolonged the culture time.The content of beta-carotene was significantly higher than the group of seawater,the content of lead?arsenic?mercury accord with national standard.Qinghai province with a vast territory and abundant sunlight,if the salt lake water can be used to culture Dunaliella Salina in Qinghai province,find the cultured potential of salt lake water,development and utilization,promoting local economic development,there will be a new choice.