The Effect of Hydroxycinnamic Acids on the Microbial Mineralisation of Phenanthrene in Soil

Abstract

The effect of hydroxycinnamic acids (caffeic, ferulic and p-coumaric acids) on the microbial mineralisation of phenanthrene in soil slurry by the indigenous microbial community has been investigated. The rate and extent of 14C–phenanthrenemineralisation in artificially spiked soils were monitored in the absence of hydroxycinnamic acids and presence of hydroxycinnamic acids applied at three different concentrations (50, 100 and 200 µg kg-1) either as single compounds or as a mixture of hydroxycinnamic acids (caffeic, ferulic and p-coumaric acids at a 1:1:1 ratio). The highest extent of 14C–phenanthrene mineralisation (P 200 µg kg-1. Depending on its concentrationin soil, hydroxycinnamic acids can either stimulate or inhibit mineralisation of phenanthrene by indigenous soil microbial community. Therefore, effective understanding of phytochemical–microbe–organic contaminant interactions is essential for further development of phytotechnologies for remediation of PAH–contaminated soils.