蛋白核小球藻培养液的循环利用

A Recycling of Culture Medium of Chlorella pyrenoidosa

【目的】探讨蛋白核小球藻采收后培养液是否能循环再用于小球藻的培养。【方法】采用小球藻分批培养完成采收细胞后所得培养废液来配制培养基,重新进入下一批次小球藻培养。以藻类BG11培养基配方为基准,按照配方全部或部分补充营养盐,通过测定藻液的光密度值间接反映藻生物量,比较小球藻在循环培养中的生长情况。【结果】在连续循环利用回收水至第4批次培养收获时培养液的光密度D(600nm)为9.9,比生长速率为0.80d^-1,与第1批培养收获时培养液的光密度D(600nm)和比生长速率相比,小球藻细胞产量和生长速率均未受影响。经过4个轮次的循环培养,用水量可减少约75%。在连续循环培养中仅补充N、P、S盐,至第3个循环小球藻收获时的生物量变化在10%以内。【结论】在加糖混养、保持连续光照、按照BG11配方补全营养盐的培养条件下,至少可对蛋白核小球藻进行4个周期的循环培养。按照BG11配方量补充相应的N、P、S盐,减少其他营养盐的投放,在2个循环周期内可以维持蛋白核小球藻的正常生长。利用培养废液实现小球藻循环经济培养和减少生产排放方法可行。

【Objective】To investigate whether the recycled water after harvesting Chlorella pyrenoidosa could be reused for the algal cultivation.【Method】The cycling medium was prepared with the remaining culture liquid after harvesting algae cells at the end of the last cultivation batch, and then was used to the next batch of cultivation. The total or partial complement of nutrients was based on the recipe BG11 of microalgae. The biomass and the growth of Chlorella pyrenoidosa was indirectly indicated by the optical density .【Result】At the end of the 4th successive cultivation batch, the optical density D(600 nm) of broth was 9.9 and the specific growth rate was 0.80 d^-1, which did not show any significant decrease comparing with the biomass concentration and the algal growth rate at the end of the first batch. After 4 successive cultivation batches, the water consumption was reduced about 75%. Only when it was supplemented with the nutrients of nitrogen, phosphorus and sulfur in successive cultivation, the change of biomass of Chlorella pyrenoidosa was controlled within 10% in two cycles.【Conclusion】The results showed that under the condition of adding sugar, maintaining continuous illumination and having total complement of nutrients based on the recipe BG11, at least four cultivation batches of Chlorella pyrenoidosa could be carried out. When it had only complement of nitrogen, phosphorus and sulfur nutrients, the growth of Chlorella pyrenoidosa could be keep in 2 successive cultivation batches. It is feasible to realize the circulatory economic cultivation of Chlorella pyrenoidosa and reduce production emissions by the recycled waste water.