几种环境因子对大龙骨藻生长与油脂合成的影响

Effects of environmental factors on growth and lipid synthesis of Tropidoneis maxima

采用单因素试验研究不同温度、光照强度和氮质量浓度对大龙骨藻生长与油脂合成的影响。结果表明：大龙骨藻生长适宜的温度为20-30℃，最适温度为25℃；低温有利于EPA和DHA含量提高，10℃时EPA和DHA含量分别占总脂肪酸的（27．98±0．97）%和（3．02±0．64）%；生长适宜的光照强度为32-48μmol/（m^2·s），而总脂含量在光照强度为80μmol/（m^2·s）时最高，达（34．66±0．86）%；低光照强度利于多不饱和脂肪酸（ PUFA）含量提高，高光照强度利于EPA含量提高；不同氮质量浓度对生长和总脂含量影响显著（P＆lt;0．05），生长适宜的氮质量浓度为20-30 mg/L，最适氮质量浓度为25 mg/L，缺氮则能促进总脂含量提高；高氮质量浓度利于PUFA和EPA的合成，随着氮质量浓度的增加，EPA和PUFA含量明显增加，氮质量浓度为25 mg/L时，EPA和PUFA含量最高，分别达（24．67±0．44）%和（40．55±0．58）%。

The effects of different temperatures, light intensities and mass concentrations of nitrogen on the growth and lipid synthesis of Tropidoneis maxima were studied. The results showed that the suitable temper-ature for the growth of Tropidoneis maxima was 20-30℃ and the optimal temperature was 25℃; lower temperature could promote the accumulation of EPA and DHA;when the temperature was 10℃, the con-tents of DHA and EPA achieved （3. 02 ± 0. 64）% and （27. 98 ± 0. 97）% respectively;the proper light in-tensity for the growth of Tropidoneis maxima was 32-48 μmol/（ m^2 ·s） , however, the total lipid content was the highest when the light intensity was 80 μmol/（m^2·s）, reaching （34. 66 ± 0. 86）%; lower light intensity was benefit for the algae to synthesize polyunsaturated fatty acids（PUFA）, while higher light in-tensity helped the algae to increase EPA content;different mass concentrations of nitrogen had great effects on the growth and total lipid content （P＆lt;0. 05）, the appropriate mass concentration of nitrogen for the growth of Tropidoneis maxima was 20-30 mg/L and 25 mg/L was the best, but nitrogen deficiency could increase the total lipid content;higher mass concentration of nitrogen promoted the synthesis of EPA and PUFA, and the contents of EPA and PUFA increased significantly with the increase of the mass concentra-tion of nitrogen;when the mass concentration of nitrogen was 25 mg/L, the contents of EPA and PUFA were the highest, reaching （24. 67 ± 0. 44）% and （40. 55 ± 0. 58）% respectively.