乙酸钠调控小球藻生长及代谢产物

Growth and metabolites of Chlorella sorokiniana regulated by sodium acetate

摘要:

[背景] 小球藻是一种单细胞绿藻，在不同培养条件下可积累高附加值的代谢产物，这些产物可用于生产生物燃料、食品、保健品、药品等。然而这些代谢产物在藻细胞中的生产率较低且很难通过经济可行的方法将其分离，这使其工业化规模生产受到限制。[目的] 研究乙酸钠对小球藻生物量的影响，并分析其对小球藻代谢产物的调控作用。[方法] 通过在小球藻培养液中添加不同浓度的乙酸钠（1.0、2.0、3.0、4.0、5.0 g/L），研究其调控小球藻生长和代谢的作用机理。[结果] 在添加3.0 g/L乙酸钠的培养液中，小球藻的生物量是对照组的5.2倍，尽管藻细胞中蛋白质含量无明显变化，但油脂和类胡萝卜素含量是对照组的2.4倍和1.2倍，多糖和叶绿素a含量却仅为对照组的54.6%和54.4%。[结论] 乙酸钠不仅会影响藻细胞的生长，还会调控其代谢过程，这为深入探索乙酸钠在调控小球藻生长及代谢过程的作用机制提供了理论基础和技术资料。

关键词:乙酸钠;小球藻;生长;叶绿素;蛋白;多糖

Abstract:

[Background] As one of the unicellular green algae, Chlorella sp. can accumulate a variety of value-added metabolites under different culture conditions. These metabolites could be used as a good feedstock to produce cosmetics, foods, health products, medicines, etc. However, their large-scale industrial production is restricted because of low productivity of metabolites in the algal cells and the difficulty of separating them by economically viable methods. [Objectives] To study the effects of sodium acetate on biomass production of Chlorella sorokiniana, and to analyze its regulatory role in the production of algal metabolites. [Methods] Different concentrations of sodium acetate (1.0, 2.0, 3.0, 4.0 and 5.0 g/L) were added to the cultures of C. sorokiniana. Growth and metabolites of this alga were determined during algae cultivation to study the regulatory role of sodium acetate. [Results] Biomass concentration of C. sorokiniana was 5.2 times higher than that in the controls, when this alga grew in the cultures with 3.0 g/L sodium acetate. Although no obvious changes in contents of proteins were observed, contents of lipids and carotenoids were 2.4 and 1.2 times greater than that in the controls, respectively, when the alga grew in the cultures with 3.0 g/L sodium acetate. In addition, contents of polysaccharides and chlorophyll a decreased, which were only 54.6% and 54.4% of that in the controls, respectively. [Conclusion] Sodium acetate not only affected the growth of C. sorokiniana, but also regulated its metabolic process. These results would provide theoretical basis and technical data for further exploring the regulatory role of sodium acetate in growth and metabolic process of C. sorokiniana.

Key words:sodium acetate;Chlorella sorokiniana;growth;chlorophyll;protein;polysaccharide