A procedure for production of adapted bacteria to degrade chlorinated aromatics

Production of biomass adapted to the degradation of a mixture of chlorobenz ene (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 a nd 30 mul 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 substrat e. The pulses of 200 mul CB and 40 mul o-DCB, were inhibitory to the bacter ial culture. Among the metabolites, muconic acid was found in large quantit ies in the medium and in the cells. At a time between two pulses of 60 min, adding 150 mul CB and 30 mul 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 whic h treated industrial waste gases contaminated by CBs. The method of adapted biomass production was described using CBs, but the d egradation of any other toxic volatile pollutant can be improved using this technique. (C) 2001 Elsevier Science B.V. All rights reserved.