雨生红球藻在红光下的生长及营养盐消耗特征

研究了在红光下雨生红球藻Haematcoccus pluvialis的细胞增殖过程中, 叶绿素荧光参数的变化以及氮磷消耗特征, 并且研究了在不同初始氮磷浓度下, 细胞增殖周期、色素变化以及氮磷消耗速率, 以期为雨生红球藻的培养工艺提供参考。结果显示: (1)在细胞增殖过程中, 光合荧光参数PSⅡ、qP、ETR与细胞增殖周期一致, 没有显著差异。Fv/Fm、NPQ则随着细胞密度的上升而下降, 随着细胞密度下降而上升, 且发生变化的拐点与营养盐胁迫造成细胞数量下降的时间点基本一致。(2)以不同初始氮磷浓度(氮磷比10:1, 重量比)的培养液接种细胞, 较高浓度的氮磷条件(45/4.5130/13.0 mg/L), 比较低浓度的氮磷条件(15/1.5 20/2.0 mg/L)有利于提高批次培养后的细胞终产量。但是, 在初始高浓度氮磷下, 接种初期细胞受到胁迫, 相对增长速率小; 氮磷消耗率低, 后期浓度维持高位; 藻细胞指数生长延迟, 培养周期变长。在红光下, 最优化的氮磷接种浓度为45/4.5 mg/L。研究结果对半连续培养雨生红球藻的应用进行了讨论。  

THE CHARACTERISTICS OF GROWTH AND NUTRIENT CONSUMPTION OF HAEMATOCOCCUS PLUVIALIS UNDER RED LIGHT

It has been proposed that Haematococcus pluvialis grow better under red light than PAR. In the present study, the characteristics of chlorophyll fluorescence parameters and nutrient requirements during population growth under red light were analyzed. The results showed that chlorophyll fluorescence parameters PS II, qP and ETR had the same variation trend along with the population growth phase. Fv/Fm and NPQ decreased with the increased cell numbers, and then increased at the late growth stage when the cell density decreased. The turning point of Fv/Fm and NPQ is practically consistent with the cell stress condition caused by nutrient depletion stress. High concentrations of the nutrients nitrogen (N) and phosphorus (P) such as 85/8.5 mg/L and 130/13.0 mg/L enhanced the biomas at early stage, and then inhibited cell growth at the longer retarded phase before entering exponential growth phase that Nutrient consumption was also reduced. These results suggested that the optimum of N/P concentration for H. pluvialis cultured under red light was 45/4.5 mg/L. The potential application of the results in semi-continuous culture of H. pluvialis has been discussed.