The secretory activity of algal cells in buffered media

Summary

The effect of the activity of algal cells on the buffering characteristics of suspending fluid was studied onChlorella 7-11-05 cells suspended in Tris buffer or in sodium citrate-citric acid buffer. It was observed that changes in the buffering capacity of the suspending fluid depended on the concentration of the original buffer, pH, and the nature of the buffer.

In Tris buffer, which is not consumed byChlorella cells, the buffering capacity, measured in terms of the van Slyke's buffer index (β), increased with time. In sodium citrate-citric acid buffer, which is used byChlorella cells in the course of their metabolism, not only the buffer index (β) changed, but also the pH at which the suspending fluid had maximum buffering capacity shifted to a new value. In both Tris and citrate buffers the newly formed buffer systems had a maximum buffering capacity at pH 6.4 corresponding to the pK₁ of carbonic acid.