研究了在 BG11 液体培养基中添加 0. 1 ~ 1. 5 mg· L ^{- 1} IAA 对微藻 TH6( Oedocladium sp.)生长和脂肪酸含量的影响。 结果表明,随培养时间的延长,微藻 TH6 的生长量逐渐增加;与对照相比,添加不同浓度 IAA 对微藻 TH6的生长均有不同程度的促进作用,其中添加1. 0 mg· L ^{- 1} IAA 对微藻 TH6 生长的促进效果最佳,至培养第33 天,微藻 TH6 的生长量比对照提高了 44. 34% 。 在培养基中添加 IAA 均能不同程度提高微藻 TH6 的总脂肪酸含量,当IAA 浓度为 0. 1、0. 5、1. 0 和 1. 5 mg· L ^{- 1}时,总脂肪酸含量分别是对照的 2. 09、2. 13、2. 41 和 1. 73 倍。 IAA 对微藻TH6 中软脂酸、硬脂酸、亚油酸和油酸含量的影响作用不同。 添加不同浓度 IAA 均能不同程度提高软脂酸的含量,当 IAA 浓度为 1. 0 mg· L ^{- 1}时,软脂酸的相对含量最高,达到了 28. 62% ;较高浓度的 IAA(1. 0 和 1. 5 mg· L ^{- 1} )能促进硬脂酸含量的提高, 低浓度 IAA(0. 1 和 0. 5 mg· L ^{- 1} )使硬脂酸含量降低;当 IAA 浓度为 0. 1 ~ 1. 0 mg· L ^{- 1}时,亚油酸含量较对照有不同程度提高;IAA 对油酸含量的影响作用不明显。 研究结果显示,含有 1. 0 mg· L ^{- 1}IAA 的 BG11 液体培养基为微藻 TH6 的最佳液体培养基。 在这一培养基中,微藻 TH6 的总脂肪酸含量最高,饱和及不饱和脂肪酸含量也较高,且微藻 TH6 生长量最大,可作为生物柴油资源进一步研究和开发。

 

Effects of 0. 1 - 1. 5 mg· L ^{- 1} IAA added in BG11 liquid medium on growth and fatty acid content of microalgae TH6 (Oedocladium sp.) were studied. The results show that the growth increment of microalgae TH6 increases as the cultivation continues. Compared to the control group, different concentrations of IAA all promote the growth of microalgae TH6 in various degrees, and the promotion effect of 1. 0 mg· L ^{- 1} IAA is the best, and the growth increment of microalgae TH6 is 44. 34% more than that of the control on the thirty-third day of cultivation. Adding IAA in BG11 liquid medium also can increase the content of total fatty acids in various degrees. When IAA concentration is 0. 1, 0. 5, 1. 0 and 1. 5 mg· L ^{- 1}, the content of total fatty acids in microalgae TH6 is 2. 09 times, 2. 13 times, 2. 41 times and 1. 73 times as much as that of the control. IAA has different effects on the contents of palmitic acid, stearic acid, linoleic acid and oleic acid in microalgae TH6. Different concentrations of IAA can enhance palmitic acid content in different degrees, and the relative content of palmitic acid reaches its peak of 28. 62% when IAA concentration is 1. 0 mg· L ^{- 1}. Higher concentration of IAA (1. 0 or 1. 5 mg· L ^{- 1}) promotes stearic acid content increasing, while lower concentration of IAA (0. 1 or 0. 5 mg · L ^{- 1} ) induces stearic acid content decreasing. When IAA concentration is 0. 1 ^{- 1}. 0 mg· L ^{- 1}, the linoleic acid content is higher than that of the control in different degrees. IAA has no obvious effect on oleic acid content. It is suggested that BG11 liquid medium containing 1. 0 mg· L ^{- 1} IAA is the best liquid medium for microalgae TH6. In this medium, the content of total fatty acids of microalgae TH6 is the highest, the content of saturated and unsaturated fatty acids higher and the growth increment the largest. So further research and development may be made on microalgae TH6 as a biodiesel resources.