Microbial degradation of three novel bisphenol compounds

Bisphenol A, 2-2-bis (4 hydroxypenyl propane) (BPA) is a synthetic compound used in the production of polycarbonate, epoxy resins and in the synthesis of the flame retardant tetrabromobisphenol A. It is found in everyday products such as plastic water bottles, food containers, furniture and textiles. The discovery of its endocrine disrupting properties in animals, as well as its persistence in anaerobic environments has motivated an active search for alternative compounds to substitute BPA in the production of food and water containers. The objective of this study was to evaluate the potential for biodegradation of three novel bisphenol analogs, which show chemical proprieties that made them suitable for substituting BPA in industrial usage. These compounds are 2-6’-dimethyl, 4-4’-dimethoxy bisphenol; 1-1’-ethyl, 2-6-dimethyl, 4-4-dimethoxy bisphenol; and 1-1’-propyl, 2-6-dimethyl, 4-4-dimethoxy bisphenol. Enrichment cultures using Arthur Kill sediment as inoculum were set under aerobic and anaerobic conditions. Analytical methods based in liquid chromatography and gas chromatography-mass spectrometry (HPLC and GC- MS) were developed. Primary enrichment cultures degraded the three test compounds under methanogenic (after 15 days), sulfate reducing (after 44 days) and aerobic conditions (after 52 days). No substrate loss was observed after 60 days under nitrate reducing conditions or in sterile controls. With transfer of the primary cultures to fresh medium (50% or 10% of the active culture) degradation continued at a higher rate. There was no loss of bisphenol A under anaerobic conditions over an incubation period of 6 months. These data suggest that the new bisphenol analogs are biodegradable under anoxic and oxic conditions where BPA is recalcitrant