Bacterial degradation of ecotoxic dehydroabietic acid

Abstract

The possibility of biodegrading dehydroabietic acid (С₂₀Н₂₈О₂, САS: 1740-19-8, abieta-8,11,13- trien-18-oic acid) (DAA), a toxic tricyclic diterpenoid, accumulated in the waste waters of the pulp and paper industry is studied using actinobacterial strain Dietzia maris IEGM 55^Т. Cells of the strain Dietzia maris IEGM 55^Т are shown to be resistant to DAA (MIC, 390 mg/L). The strain is not able to use DAA as its sole source of carbon and energy. DAA (500 mg/L) decays almost completely in 7 days when the bacteria are preliminarily grown with n-hexadecane. The DAA effect on the viability and respiratory activity of the bacteria is studied. Analysis of the antimicrobial activity shows that extracts of the obtained metabolites are not toxic, in contrast to the initial substrate. The resulting data expands our views on the catalytic activity of actinobacteria and their impact in decontaminating natural ecosystems that contain ecotoxicants.