Assessment Of Lipid Detection Methods On Chlorella. Pyreinodoisa, And The Establishment Of The Photobioreactor System Of Microalgae Chlorella

As the material of biodiesel，Chlorella has many advantages, such as high photosynthetic efficiency,environmental adaptation ability, short growth cycle, high biological production and high producing oil. Inthis experiment, an easy way to check out the lipid content of the microalgae Chlorella is design. AndChlorella cultured in the optimal conditions of photobioreactor to increase the lipid production.There mainly are three ways to check out the lipid content of the microalgae Chlorella pyrenoidosa-Bligh-Dyer method, vanillin colorimetric method and Nile-red method, and comparing and analyzing theefficiency and sensitivity of these methods, and then get the optimized lipid detection method. The resultindicated that the result of classical gravimetric method is accurate, but the gravimetric method isinsensitive (minimum detectable amount:100mg). Vanillin colorimetric method and Nile-red method aresimple and sensitive. The minimum detectable amount of vanillin colorimetric method is10mg, and thedetection range of optimized vanillin colorimetric method is0.5mg-3.0mg. the detection range of Nile-redmethod is0.0588mg/ml-0.588mg/ml. In conclusion, it shows an easy way to check out the lipid content ofthe microalgae Chlorella pyrenoidosa with the optimized vanillin and Nile-red method; it provides atechnical approach to trace and rapid detection the lipid content of the energy microalgae.The effects of the environmental factors including culture medium, air aeration rate, nitrogenconcentration, Fe3+concentration, IAA concentration, CO2supply volume on the growth rate and lipidaccumulation of the microalgae Chlorella pyrenoidosa F-9in airlift photobioreactor were studied. Resultsshowed that when the air aeration rate was2.0L/min the growth rate of Chlorella was6.17mg·l-1·d-1andthe lipid production was1.77mg.l-1.d-1. The algal growth rate increased with increasing nitrogenconcentration, while the lipid content decreased. In total, the nitrogen concentration did not affect the lipidproduction of C. pyrenoidosa significantly. The growth rate of C. pyrenoidosa was maximized to7.29mg·l-1·d-1when the Fe3+concentration was0.1mmol/L, and the lipid production was maximized to2.54mg.l-1.d-1when the Fe3+concentration was1mmol/L. When the IAA concentration was1.0mg/L, the algalgrowth rate and lipid production were maximized to7.47mg·l-1·d-1and2.89mg.l-1.d-1respectively. Whenthe CO2supply volume was60min/d the growth rate of Chlorella was maximized to9.88mg·l-1·d-1, andwhen the CO2supply volume was40min/d, the lipid production of Chlorella was maximized to3.86mg.l-1.d-1. In this experiment, the lipid production of Chlorella cultured in the optimal conditions ofphotobioreactor is3.44times more than the original group.