Bacillus sphaericus 2362 spore sedimentation was evaluated through batch settling experiments, using tannin as the flocculating agent. The flocculation was demonstrated to be efficient up to the tannin concentration of 150 ppm. The floc... more
Bacillus sphaericus 2362 spore sedimentation was evaluated through batch settling experiments, using tannin as the flocculating agent. The flocculation was demonstrated to be efficient up to the tannin concentration of 150 ppm. The floc diameter averaged 208 µm, and its density was found to be 1.09 g/mL. The sedimentation process using tannin as a flocculating agent is promising, and a spore concentrate was obtained without loss of biological activity, presenting a LC50 equal to 0.22 ppm. The result indicates that the larvicide activity is appropriate for controlling populations of Culex quinquefasciatus.