The Physiological Responses Of Dunahella Sauna And Playtmonas Subcordiformis.(wille)Hazen To Nutrients Changes

Dunaliella salina belongs to Chlorophyta, Chlorophyceae, Volvocales, Dunaliellaceae,Dunaliella and Platymonas subcordiformis.(wille)Hazen belongs to Chlorophyta,Chlorophyceae, Volvocales, Chlamydomonadaceae, Platymonas, which are the two of themost famous economic algae in producing astaxanthin.In this paper, the effects of different contcentration of nitrogen, phosphorus, N:P ratios,salinity, temperatures, light intensity and pH on the growth and metabolism of Dunaliellaand Platymomnas helgolandica tsingtaoensis were studied. Results of investigation couldsupply some useful experimental basis for the theory to Dunaliella and Platymomnashelgolandica tsingtaoensis enormously.(1) In a certain range of concentration of nitrogen, increasing nitrogen concentrationis conducive to the biomass of Dunaliella and Platymomnas helgolandica tsingtaoensis.Two microalgae species is positive correlation with nitrogen concentration, the greateralgae stable cell density is, the higher chlorophyll a content is. When N concentration is1.2g/L, the dissoluble polysaccharides content of two microalgae species is the most,indicating the high N concentration is conducive to the secretion and accumulation ofdissoluble polysaccharides content. roteins are the basis of energy substances of celldivision. The soluble proteins within the two microalgae species were significantlyaffected by different N concentrations. The protein content of algae increased with Nconcentration. The most appropriate N concentration is1.2g/L.(2) The low phosphorus conditions are conducive to the biomass of Dunaliella andPlatymomnas helgolandica tsingtaoensis. The most appropriate P concentration ofDunaliella is0.025g/L. The most appropriate P concentration of Platymomnashelgolandica tsingtaoensis is0.03g/L. Two microalgae species is positive correlation withP concentration, the greater algae stable cell density is, the higher chlorophyll a content is.When P concentration is0.015g/L, the dissoluble polysaccharides content of twomicroalgae species is the most. The protein content of algae increased with P concentration.The most appropriate P concentration is0.03g/L.(3) By experimental data, the suitable N:P ratios of Dunaliella is16:1, the suitable N:P ratios of Platymomnas helgolandica tsingtaoensis is80:1. Two microalgae species ispositive correlation with N:P ratios, the greater algae stable cell density is, the higherchlorophyll a content is. When N:P ratios is1:1, the chlorophyll a content of twomicroalgae species is the least. When N:P ratios is160:1, the chlorophyll a content of twomicroalgae species is the most, indicating that low N:P ratios are not conducive to thesecretion and accumulation of dissoluble polysaccharides content. The protein content ofalgae increased with N:P ratios.(4) Low salinity can increase the growth rate and extend the logarithmic growth phaseof Dunaliella and Platymomnas helgolandica tsingtaoensis. The most appropriate is from30to40. When salinity is30, the chlorophyll a content of two microalgae species is themost. When salinity is30, the chlorophyll a content of Dunaliella is the most. Whensalinity is40, the dissoluble polysaccharides content of Platymomnas helgolandicatsingtaoensis is the most. When salinity is40, the protein content of Dunaliella is the most.When salinity is30, the protein content of Platymomnas helgolandica tsingtaoensis is themost.(5) When the temperature is25℃, Dunaliella and Platymomnas helgolandicatsingtaoensis have maximum density. When the temperature is30℃, the chlorophyll acontent of Dunaliella is the most. When the temperature is25℃, the chlorophyll a contentof Platymomnas helgolandica tsingtaoensis is the most. When the temperature is30℃, thedissoluble polysaccharides content of Dunaliella is the most. When the temperature is25℃, the dissoluble polysaccharides content of Platymomnas helgolandica tsingtaoensis isthe most. The protein content of algae reduced with temperature increased.(6) Different light intensity gradient of the final culture density of Dunaliella fromhigh to low is:4000lx＞3000lx＞5000lx＞6000lx＞2000lx＞1000lx＞7000lx. Differentlight intensity gradient of the final culture density of Platymomnas helgolandicatsingtaoensis from high to low is:5000lx>3000lx>7000lx>9000lx>11000lx>1000lx.When light intensity is5000lx, the chlorophyll a content of Dunaliella is the most. Whenlight intensity is9000lx, the chlorophyll a content of Platymomnas helgolandicatsingtaoensis is the most. When light intensity is4000lx, the dissoluble polysaccharidescontent of Dunaliella is the most. When light intensity is7000lx, the dissoluble polysaccharides content of Platymomnas helgolandica tsingtaoensis is the most. Whenlight intensity is4000lx, the protein content of Dunaliella is the most. When light intensityis7000lx, the protein content of Platymomnas helgolandica tsingtaoensis is the most.(7) Different pH gradient of the final culture density of Dunaliella from high to low is:7＞8＞9＞6＞11＞10＞5. Different pH gradient of the final culture density ofPlatymomnas helgolandica tsingtaoensis from high to low is:8>7>6>9>10>5. WhenpH is7, the chlorophyll a content of Dunaliella and Platymomnas helgolandicatsingtaoensis is the most. When pH is7, the dissoluble polysaccharides content ofDunaliella and Platymomnas helgolandica tsingtaoensis is the most. When light intensityis7000lx, the dissoluble polysaccharides content of Platymomnas helgolandicatsingtaoensis is the most. When pH is7, the protein content of Dunaliella andPlatymomnas helgolandica tsingtaoensis is the most.