Capacity of chromium VI bioremediation from waste waters of tanneries by Pseudomonas sp and its effect over the cellular cycle of Allium cepa

Abstract

In order to evaluate the capacity of chromium VI bioremediation from waste waters of tanneries by Pseudomonas spand its effect over the cellular cicle of Allium cepa, it was worked in a bioreactor of stirring tank, adding glucose, 6 amino acids, mineral salts as nutrients and an inocuclum at equivalent concentration of 3 x 10 cell/mL. The process was monitored every 24 hours during 6 days, by means of: Determination of total chromium and VI chromium by atomic absorption spectrophotometry; microbial recount by the poured badge method and pH determination by potentiometer. It was observed that Pseudomonas sp. doesn't carry out a significant reduction of VI chromium, -4 because only reduces it in 13,51%, with a rate of reduction of 4,16 x 10 ppm/h, while total chromium reaches a considerable reduction at the 24 hours passing from 2460 to 340 ppm. With a rate of reduction of 89.166 ppm/h. It was observed that in this same time of treatment the bacterial population reaches its logarithmic phase, reaching a growth rate of 0,198/h, and that the population begins to diminish since the 24 hours, after the 24 hours there is not reduction of total chromium in appreciable quantities. When determining the effect on the cellular cycle of Allium cepa it was observed that cellular damage takes place at all the concentrations. It was concluded that was not reached a level of enough reduction to avoid the cellular damage and to be acceptable according to the standards of saneation of residual waters.