Fig. 7From: Pre-concentration of microalga Euglena gracilis by alkalescent pH treatment and flocculation mechanism of Ca3(PO4)2, Mg3(PO4)2, and derivativesThe concentration change of dissolved a Ca2+ and b Mg2+ in the PEM medium adjusted to pH 8.5. Control represents the medium without pH treatment. NS, ** represent p > 0.05, p < 0.01, respectively. The values represent mean ± S.D. n = 3Back to article page