富碳培养对海洋富油微藻油脂积累特性的影响

EFFECT ON LIPID ACCUMULATION OF MARINE OLEAGINOUS MICROALGAE UNDER CO_2 ENRICHMENT CULTIVATION

实验针对三株海洋富油微藻:球等鞭金藻(Isochrysis galbana CCMM5001)、一种等鞭金藻(Isochrysis sp.CCMM5002)和一种微拟球藻(Nannochloropsis sp.CCMM7001),研究了它们在通入0.03%(空气)、5%、10%三个浓度CO2培养条件下的生长特性,同时考察了其总油脂及中性脂的累积情况。结果显示,富碳培养有利于这三株海洋微藻的生长,但最适生长的CO2浓度不同。球等鞭金藻(Isochrysis galbana CCMM5001)和等鞭金藻(Isochrysis sp.CCMM5002)在通入10%CO2时具有最大产率,分别达到(182.28±7.07)mg/(L·d)和(164.22±7.10)mg/(L·d),而微拟球藻在通入5%时具有最大产率,达到(122.25±1.17)mg/(L·d),随着CO2浓度的增加,三株海洋微藻的总脂含量和中性脂含量有明显提高。在通入10%CO2条件下,球等鞭金藻(Isochrysis galbana CCMM5001)、等鞭金藻(Isochrysis sp.CCMM5002)和微拟球藻(Nannochloropsis sp.CCMM7001)的总脂含量分别达到(45.15±4.03)%、(47.15±1.20)%和(41.20±1.69)%;从中性脂的累积规律来看,三株藻均在平台期的累积达到最大,脂肪酸分析结果表明三株藻种适合制备生物柴油的C14-C18系脂肪酸相对含量在不同CO2条件下基本保持不变,维持在90%左右。实验结果显示,研究的藻株作为富油高固碳优良藻株,具备用于海洋生物质能耦合CO2减排开发的潜力。

Three marine oleaginous microalgae lsochrysis galbana CCMM5001, lsochrysis sp. CCMM5002 and Nan- nochloropsis sp. CCMM7001 were cultured under different CO2 concentrations of ambient air （0.03%）, 5% and 10% respectively. The growth characterization, total and neutral lipid accumulation of these microalgae were investigated. The results showed that CO2 enrichment cultivation could increase the growth of all three microalgae, but the optimum CO2 concentrations were different. The maximum biomass yield oflsochrysis galbana CCMM5001 and lsochrysis sp. CCMM5002 were （182.28±7.07） mg/（L-d）and （164.22±7.10） mg/（L.d） when culturing with 10% CO2. However, the maximum biomass yield of Nannochloropsis sp. CCMM7001 was （122.25±1.17） mg/（L.d） when culturing with 5% CO2. As the CO2 concentration increasing, the total lipid and neutral lipid of these microalgae increased significantly. When culturing with 10% CO2, total lipid content of lsochrysis galbana CCMM5001, Isochrysis sp. CCMM5002 and Nan- nochloropsis sp. CCMM7001 were （45.15±4.03）%, （47.15±1.20）% and （41.20±1.69）% respectively. The maximum neutral lipid content of all three microalgae could be accumulated in stationary phase. The fatty acid analysis of the microalgae showed the relative content of C14-C18 fatty acid which suitable for biodiesel preparation maintained at 90% when culturing with different CO2 concentrations. The results indicate the marine oleaginous microalgae in this study have high carbon dioxide fixation ability They are the potential excellent strains and could be used in marine bio-energy development coupled with CO2 emission reduction.