Evaluation of biodegradable plastics as solid hydrogen donors for the reductive dechlorination of fthalide by Dehalobacter species

Biodegradable plastics (BPs) were evaluated for their applicability as sustainable and solid H-2 donors for microbial reductive dechlorination of 4,5,6,7-tetrachlorophthalide (fthalide). After a screening test of several BPs, the starch-based plastic (SP) that produced the highest levels of H-2 was selected for its use as the sole H-2 donor in this reaction. Fthalide dechlorination was successfully accomplished by combining an H-2-producing SP culture and a KFL culture containing Dehalobacter species, supplemented with 0.13% and 0.5% SP, respectively. The efficiency of H-2 use in dechlorination was evaluated in a combined culture containing the KFL culture and strain Clostridium sp. Ma13, a new isolate that produces H-2 from SP. Results obtained with this culture indicated increased H-2-fraction for fthalide dechlorination much more in this culture than in compared with a KFL culture supplemented with 20 mM lactate, which are 0.75 H-2.glucose(-1) and 0.015 H-2.lactate(-1) in mol ratio, respectively. (C) 2012 Elsevier Ltd. All rights reserved.