Structural and metabolic profiling of Lycopersicon esculentum rhizosphere microbiota artificially exposed at commonly used Non-Steroidal Anti-Inflammatory Drugs

Abstract

In this study the effect of common non-steroidal anti-inflammatory drugs on Lycopersicon esculentum rhizosphere microbiota was monitored. Results evidenced that rhizosphere microbiota abundance decreased especially under exposure to diclofenac and ibuprofen while fungal/bacteria ratio changed significantly with exposure to diclofenac and ketoprofen. Compared with control samples the average amount of ratio of gram negative/gram positive bacteria was higher in rhizosphere soil contaminated with ibuprofen and lower in case of diclofenac contamination. Carbon source consumption increased with time of assay in case of control samples and those contaminated with diclofenac. This suggests that rhizosphere microbiota under contamination with diclofenac consume higher amount of carbon although do not consume a larger variety of its sources. In case of contamination with ibuprofen and ketoprofen the consumption of carbon source presents a decreasing tendency after day 30 of the assay. Rhizosphere microbiota emitted volatile organic compounds were also monitored. Volatile compounds belonging to alcohol, aromatic compounds, ketone, terpene, organic acids, aldehyde, sulphur compounds, esters, alkane, nitrogen compounds, alkene and furans were detected in rhizosphere soil samples. Among these, terpene, ketone, alcohol, aromatic compounds, organic acids, and alkane were the most abundant compound classes, but their percentage changed with exposure at diclofenac, ketoprofen and ibuprofen. Such changes in abundance, structure, and metabolic activity of Lycopersicon esculentum rhizosphere microbiota under exposure to common non-steroidal anti-inflammatory drugs make as to suppose that there is a probability to also change ecosystem services provided by rhizosphere microbiota.