[关键词]
[摘要]
微藻的脂肪酸含量与其应用价值有直接关系,而环境因素对微藻脂肪酸含量有着显著影响。本文以细胞密度、干重浓度、脂肪酸含量等为评价指标,研究了户外跑道池系统中不同盐度(20‰、25‰和30‰)、pH值(7.5、8.0和8.5)、氮源种类(尿素和碳酸氢铵)等环境因素下三角褐指藻户外生长、脂肪酸积累的规律。结果表明,随着培养基盐度的升高,三角褐指藻的增长速率变缓,在20‰盐度条件下获得最大生物量177.78 mg/L;在30‰盐度条件下获得最大脂肪酸含量123.99 mg/g;pH值8.0条件下,三角褐指藻生物量浓度及脂肪酸含量均达到最大值(166.39 mg/L和145.92 mg/g),而在pH值7.5条件下,三角褐指藻的生长受到抑制。尿素作为氮源较碳酸氢铵更有利于三角褐指藻的生长,最终生物量为150.83 mg/L,但以碳酸氢铵为氮源条件下,更利于脂肪酸的积累,脂肪酸含量达到169.72 mg/g。因此,户外跑道池中的最适培养条件为盐度20‰、pH值8.0、尿素为氮源。
[Key word]
[Abstract]
The content of fatty acids in microalgae was directly related to its application value, and the the environmental factors had a significant effect on the content of fatty acids in microalgae.,In this study, cell density, dry weight concentration and fatty acid content were used as the evaluation indexes to investigate the rules of outdoor growth and fatty acid accumulation of Phaeodactylum tricornutum under different environmental factors such as salinity (20‰, 25‰, 30‰), pH value (7.5, 8.0, 8.5) and nitrogen source (urea, ammonium bicarbonate). The results showed that the growth rate of P. tricornutum slowed down with the increase of salinity in culture medium. The maximum biomass (177.78 mg/g) was obtained under the condition of 20‰ salinity and the maximum fatty acid content was 123.99 mg/g under the condition of 30‰ salinity. In addition, the biomass and fatty acid content of P. tricornutum reached the maximum (166.39 mg/L and 145.92 mg/g, respectively) at pH 8.0, and the growth of P. tricornutum was inhibited at pH 7.5. The urea, used as nitrogen source, was more suitable than ammonium bicarbonate for the growth of P. tricornutum and the final biomass was 150.83 mg/L. Compared to urea, the ammonium bicarbonate was more advantageous for the accumulation of fatty acid, and the fatty acid content was 169.72 mg/g. Consequently, the optimum conditions for P. tricornutum were as follows: salinity, 20‰; pH, 8.0; , nitrogen source ,urea.
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[基金项目]
广东省公益研究与能力建设项目(2015A020216003、2016A010105001);广东省海洋渔业科技与产业发展专项(A201401C01)资助;国家自然科学基金项目(31370383);广州市科技计划项目产学研协同创新重大专项(201704030084)