Simulated Microgravity Effect The Development Of The Reactor And The Culture Of Spirulina

A microgravity simulation reactor was designed to cultivate the S.platensis,based on the design philosophy of all kinds of elinostats and photobioreactors categories.Then introducing a few optimization methods used in optimization medium and technological conditions,finally determining to select response surface methodology to optimize the cultivation condition of S. platensis according to the feature of Response surface methodology firrstly.Employing the response surface methodology to optimize the cultivation condition of photoautotrophy and nutritional ingredient of mixtrophy,relatively.The whole experiments were accomplished in the self-made 400mL microgravity simulation reactor.In the photoautotrophy, three critical factors selected for investigation were rotary speed of vessel,cultivation time and light intensity.Researching the optimization levels and the relations between these factors and building a quadratic regression equation with DW as the dependent:DW=-1.62+0.084A+0.18B+6.732E-004C+5.750E-003AB-7.500E -007AC+2.125E-005BC-6.164E-003A²-0.015B²-1.256E-007C²By solving the inverse matrix from the equation,the optimal conditions for obtaining the maximum 1.02g/L of DW were 11rpm,10d,and 3.5klx respectively.The experiments for validating the quadratic regression equation proofed the model had played well in a role in the practice.On the base of the photoantotrophy,the first step of mixtrophy was one-factor experiment to searoh the optimum concentration of nutritional ingredient which could promote the growth of Sp obviously.In the course of the mixtrophy experiment,two ingredients(organic substrate, Glucose and oxidation inhibitor,Na₂S₂O₃) were chosen to add to culture medium.The optimum concentration is Na₂S₂O₃ 1.0g/L and Glucose 2.0g/L respectively when adding supplements separately.At last,the result of experiment showed that maximum DW is 1.39g/L when supplement concentration is Na₂S₂O₃ 1.0g/L and Glucose 2.0g/L,respectively.And the DW is 2.78 times as much as large-scale cultivation of Spirulina.To a certain extent,it improves the DW value.It also proved that Na₂S₂O₃ has much better antioxidation and Glucose is quite good organic substance promoting the growth of Spirulina.The result of experiment proved that the bioreactor is propitious to cultivate the S.platensis. So it provides some experimental and theoretical data for the application of Spirulina in space flight by using the microgravity simulation reactor to culture Spirulina.