Project R-5404

Biodegradation of organic contaminants by endophytic bacteria in halophytes (Research)

The success of a phytoremediation strategy on organic polluted soils depends on the extent of the phytotoxicity caused by the pollutant to the host plant. The idea of exploiting endophytic bacteria in phytoremediation strategies is becoming increasingly popular because (a) endophytes can affect beneficially the plant growth, (b) contribute to the plant detoxification and (c) often exhibit more beneficial effects over rhizosphere bacteria. Endophytic bacteria are defined as the bacteria inhabiting the plant internal tissues without causing any negative effect and have been isolated from numerous plant species. The putative endocrine disruptor, bisphenol A (BPA, 2,2-Bis(4-Hydroxyphenyl) propane), was selected as an organic pollutant because its annual production and use have been increasing and it has been found not only in environmental samples but also in human tissues. In addition, it might cause reproductive toxicity and it may stimulate cellular responses and alter cell functions , even at very low concentrations. The final aim of this project is to generate robust plants with recruited endophytic bacteria that have the potential to clean up BPA from soil and groundwater and can be implemented in phytoremediation strategies in polluted areas. In order to accomplish this goal, the diversity of the culturable endophytic community associated with two different halophytic species (Tamarix parviflora and Juncus acutus) growing on BPA contaminated soil and groundwater will be assessed. Endophytic bacteria that have the ability to degrade the pollutant (BPA) and simultaneously promote plant growth will be identified. Next the effect of the most promising indigenous bacteria and a known BPA degrader isolated from a wastewater treatment plant will be investigated. In detail, bacteria will be inoculated in the halophytes and their ability to efficiently colonize the plant and their distribution in the plant compartments will be monitored. The potential effects on the halophytes' performance regarding the Bisphenol-A removal from soil and water and on the plant growth of inoculated plants will be evaluated.

01 May 2014 - 31 December 2015