产油微藻的选育及其培养条件优化

为了利用微藻处理废水生产生物质燃料,实现治理环境污染和缓解化石能源短缺的耦合,需要筛选能够适应石家庄本地气候,生产状况良好且油脂产率较高的微藻藻株。从石家庄市自然河流中采样,经过BG11培养基分离纯化后筛选出10株微藻,利用SPASS 19.0软件对培养中的相关数据进行方差分析及LSD多重比较发现,自养条件下藻种DK-3生物量、总脂含量较其他藻株高,分别为:1.86g·L-1、(10.23±2.63)mg·L-1·d-1,经18S rDNA鉴定为栅藻(Scenedesmus meyen),构建其系统发育树。利用Box-Behnken Design(BBD)设计耦合响应曲面法(RSM)探索藻种DK-3最佳异养培养条件,最终藻种DK-3最佳培养条件为葡萄糖20g·L-1、K 2 HPO 4·3H 2 O 90 mg·L-1、MgSO 4·7H 2 O 200 mg·L-1(其他成分参考BG11培养基),经验证在此培养条件下,经240 h培养后生物量为5.47g·L-1,油脂产量为1.28g·L-1,比对照组生物量3.37g·L-1提高了62.31%,因此,藻种DK-3具有较高的研究潜能。

Microalgae Breeding with High Efficient of Oil-producing and Optimization of Cultivation Conditions

It is necessary to screen microalgae strains that can adapt to the climate of Shijiazhuang because the feasibility of using microalgae in wastewater treatment as a supplement for wastewater treatment can couple between environmental pollution control and the alleviation of fossil energy shortage. In this paper, 10 microalgae strains were selected after purification from rivers in Shijiazhuang city by using BG11 medium. The data of all microalgae strains culture were shown that the DK-3 was the best one than others with the high biomass(1.86 g·L-1) and the high total fat content [(10.23±2.63) mg·L-1·d-1] under the autotrophic condition by variance analysis with SPSS 19.0 and LSD multiple comparison. The DK-3 was identified as Scenedesmus meyen and the phylogenetic tree was constructed by 18S rDNA sequencing analysis. In order to explore the optimal heterotrophic conditions of algae DK-3, the experiment scheme was designed by couple between Box-Behnken design (BBD) and response surface method (RSM). The result showed that the best culture condition of DK-3 was the BG11 with glucose 20 g·L-1, K2HPO4·3H2O 90 mg·L-1, and MgSO4·7H2O 200 mg·L-1, respectively. Compared with the biomass (3.37 g·L-1) of unoptimized group, the biomass (5.47 g·L-1) and oil yield (1.28 g·L-1) of DK-3 under the optimized conditions above was increased by 62.31% after 240 h training. Therefore, the DK-3 is a good algae with a high research potential.