A procedure for production of adapted bacteria to degrade chlorinated aromatics

Abstract

Production of biomass adapted to the degradation of a mixture of chlorobenzene (CB) and 1,2-dichlorobenzene (DCB) was investigated in a batch culture with substrates supplied by pulses. CB and o-DCB concentrations which gave the best adapted biomass productivity were determined and found to be 150 and 30 μl l −1, respectively. The biomass productivity was 51 mg l −1 h −1. The biomass yield was 0.38 g of biomass dry weight per gram of substrate. The pulses of 200 μl CB and 40 μl o-DCB, were inhibitory to the bacterial culture. Among the metabolites, muconic acid was found in large quantities in the medium and in the cells. At a time between two pulses of 60 min, adding 150 μl CB and 30 μl o-DCB per each pulse, 7.6 g l −1 of biomass was obtained. The produced biomass served as an inoculum for the biotrickling filter which treated industrial waste gases contaminated by CBs. The method of adapted biomass production was described using CBs, but the degradation of any other toxic volatile pollutant can be improved using this technique.