添加不同营养物质对裂殖壶菌油脂反耗期磷脂DHA含量的影响

Effect of nutrient addition on phospholipids containing DHA produced by Schizochytrium sp. in lipid consumption stage

研究油脂反耗过程中不同营养物质的添加对裂殖壶菌胞内油脂含量、油脂组分及各油脂组分中DHA含量的影响,开发一种能够有效提高胞内油脂中磷脂DHA含量的营养物质添加方法。结果表明:单营养物质添加实验发现谷氨酸钠、乙醇可以有效缓解反耗期油脂含量的降低;磷酸二氢钾、乙醇、硫酸铵可以有效提高胞内极性脂的含量;酵母膏、硫酸铵可以有效提高极性脂中DHA的含量。多种营养物质复配添加实验发现,谷氨酸钠-磷酸二氢钾复配添加效果最佳,添加后,胞内油脂含量维持在26.65 g/L,与未添加营养物质相比,提高了44.52%;其中极性脂占总油脂的49.08%,极性脂中DHA含量达到54.65%,PUFA与SFA比值为4.48。

The effects of adding different nutrients on lipid content, lipid composition and DHA content of Schizochytrium sp. in lipid consumption stage were investigated so as to develop a method for improve- ment of phospholipids containing DHA content in Schizochytrium sp. cellular lipid. The results showed that single nutrient addition experiment found that reduction of lipid content could be relieved effectively by adding sodium glutamate and ethanol. Adding KH2PO4, ethanol and （NH4 ）2SO4could enhance cellu- lar polar lipid content. Multi - nutrients addition experiment found that compound addition of sodium glu- tamate and KH2PO4 had the best effect. Compound addition of sodium glutamate and KH2PO4 could keep the lipid content at 26.65 g/L, increasing by 44.52% compared with no addition of nutrient, in which the polar lipid content accounted for 49.08% of the total lipid. What＇ s more, DHA content in polar lipid reached 54.65% , and the ratio of PUFA to SFA was 4.48.