The Impact Of Carbon Source On Haematococcus Pluvialis Growth,Astaxanthin Accumulation And Optimization Of Culture Conditions

Astaxanthin has the powerful capacity of scavenging free radical. Its antioxidant function is 550 times higher than vitamin E, and higher than carotene, zeaxanthin, gall flavin and lutein, which is known as "super-oxidants." Haematococcus pluvialis has the highest content of natural astaxanthin which are 3S,3S’isomers, an ideal natural astaxanthin producer. In this paper, Haematococcus pluvialis stored in laboratories are used and the production of astaxanthin is as an indicator. In the conversion stage of Haematococcus pluvialis, horizontal comparisons were made. With mixed nutrition, the best converting carbon sources were chosen, added an equal amount of carbonaceous substance concentration of sodium acetate, glucose, sodium pyruvate. The results showed that under mixd culture conditions, csodium pyruvate and glucose are better for the growth of pluvialis algae and accumulation of carbon sources of astaxanthin. With a dosage of carbonaceous material of 0.10mol/L, astaxanthin producation was 6.0346 ± 0.427mg·L-1. On the study of the concentration of Haematococcus pluvialis during conversion period, the concentration of sodium pyruvate were set to the amount of carbon material 0.075,0.080,0.085,0.075,0.095, 0.100,0.105,0.110 mol/L. With the CCD experiment, the culture conditions were optimized under the best conversion of carbon source--acetone sulfonic acid sodium, and the optimal concentration of the amount of carbon--0.01 mol/L. The conversion light is 149.25 μ mol photons m-2s-1; temperature,28.98℃; time,10.48d; and pH is 10. So the content of astaxanthin is 13.086±0.238mg·L-1,1.39 times as large as the original condition. In the study of the influence of the mixed nutrition of sodium acetate and sodium pyruvate on the accumulation and conversion of astaxanthin of Haematococcus pluvialis. Based on the conditions of the optimal concentration of sodium acetate,0.02mol/L and of sodium pyruvate, 0.10mol/L, the acetic acid sodium and sodium pyruvate were added by two forms:First, two carbon sources were used simultaneously; Second, a carbon source was used first and another was replaced several days later. The results are as follows. First, when the two carbon sources were used simultaneously, the production of astaxanthin were th highest--10.836±0.583mg·L-1, with the amount of carbonaceous material of sodium pyruvate, 0.10mol/L and of sodium acetate, 0.01mol/L. Second, using sodium pyruvate first and then replaced by sodium acetate after eight days, the production of astaxanthin were the highest-- 10.887±0.315 mg·L-1.