摘要：
为优化大龙骨藻的营养盐条件,采用单因素试验研究了铁源,铁、磷和硅质量浓度对大龙骨藻的影响.结果表明:磷、铁、硅对大龙骨藻的生长、总脂含量和脂肪酸组成影响显著(P<0.05);大龙骨藻最适生长、EPA和PUFA积累最高的磷质量浓度为2 mg/L,EPA和PUFA含量分别为(24.48±2.05)%、(40.12±1.38)%;最佳铁源为FeSO4,生长最适铁质量浓度为0.5 mg/L;低铁质量浓度利于总脂积累,铁质量浓度0.25 mg/L时总脂含量高达(37.74±2.29)%;高铁质量浓度利于EPA和PUFA积累,铁质量浓度0.5 mg/L时EPA和PUFA含量最高,分别为(25.16±1.22)%和(42.75±2.12)%;生长适宜的硅质量浓度为0.5~1 mg/L,低硅质量浓度利于总脂和PUFA的积累,硅质量浓度0 mg/L时,EPA和PUFA含量最高,分别为(28.15±1.00)%和(40.88±0.06)%.综上所述,大规模培养大龙骨藻时,可采取二步法培养,即先培养获得高生物量,后进行磷、铁、硅质量浓度的调控,获得总脂、EPA及PUFA较高水平的积累.%In order to optimize nutrient conditions of Tropidoneis maxima,the effects of iron sources and mass concentrations of phosphorus, iron and silicon on Tropidoneis maxima were studied by single factor ex-periment. The results showed that the effects of phosphorus, iron and silicon on the growth, total lipid con-tent and fatty acid composition of Tropidoneis maxima were significant(P<0. 05). The optimal mass con-centration of phosphorus for growth and accumulations of EPA and PUFA was 2 mg/L, and the contents of EPA and PUFA were (24. 48 ± 2. 05)% and (40. 12 ± 1. 38)%, respectively. The optimal iron source was FeSO4 , and the optimal mass concentration of iron for growth was 0. 5 mg/L. Lower mass concentration of iron promoted accumulation of total lipid. When mass concentration of iron was 0. 25 mg/L, the content of total lipid reached up to (37. 74 ± 2. 29)%. Higher mass concentration of iron promoted accumulations of EPA and PUFA. When mass concentration of iron was 0. 5 mg/L, the contents of EPA and PUFA were the highest, reaching (25. 16 ± 1. 22)% and (42. 75 ± 2. 12)%, respectively. The optimal mass concentration of silicon for growth was 0. 5-1 mg/L. Lower mass concentration of silicon promoted accumulations of total lipid and PUFA. When mass concentration of silicon was 0 mg/L, the contents of EPA and PUFA were the highest, up to ( 28. 15 ± 1. 00 )% and (40. 88 ± 0. 06)%, respectively. The two -step method could be taken in large-scale culture of Tropidoneis maxima to firstly obtain higher biomass, then obtain higher accumulations of total lipid, EPA and PUFA by regulating mass concentrations of phosphorus, iron and silicon.
