摘要
在大量培养单细胞绿藻的工作中，怎样把已经培养出来的藻类进行收获，是一个生产上的关键问题。这些藻类的个体很小，悬浮在水中，即使在培养液内繁殖到浓度很高时，我们要进行收获也有许多困难。一般采用的收获方法是浓缩，把水滤去，得到浓浆，然后经过晒干以取得藻粉。浓缩的最好的方法是采用各种办法使藻类沉淀。
The harvesting of the products in the mass culture of unicellular green algae is one of the most important procedures in their cultivation,but its problems are not yet completely solved. In the mass culture of Scenedesrnus obliquus we have tried·HC1,KOH,NaOH,Al_2(SO_4)_3; CaO,and saturated lime-water(Ca(OH)_2)as agents for precipitating the algae in cultures.Among these,HCl,KOH and NaOH are not very effective,and after treatment the algae become yellowish and precipitate very slowly.On the other hand,treatment with 0.03—0.05% of alum,or with 6.0% of saturated lime-water,results in the complete precipitation of the algae within 2 hours.It is, however,of considerable interest,that if we add lime directly to the culture medium,no or very little effect is observed.Also,the use of vessels of different shapes for when carrying out these treatments with chemicals,shows some influence on the rate of precipitation of the algae. Although the mechanisms involved in the precipitation of cultivated algae by saturated lime-water are not completely known,it remains certain that this method is an effective one,and is of practical value in the mass culture of algae and their more efficient harvesting.
