QUANTIFICATION OF EXUDATION FOR THE PLANT-MICROBIAL FUEL CELL

摘要

The efficiency and scale of Plant Microbial Fuel Cells (Plant-MFC) need to be optimized. The amount ofexudates released by the plant is one of the limiting processes of the plant-MFC. Three strategies to study exudation have been reported: sampling of a non-sterile root environment (1, 2, 3, 4), sampling of a root environment treated with antimicrobial agents (5, 6, 7, 8) and sampling of a sterile root environment (9, 10, 11, 12). Initial measurements wth HPLC in the non-sterile root zone of tomato plants showed that exudate concentrations were close to the detection limit. These low amounts of exudatesmeasured can be the effect of microbial breakdown at the root-soil interface. Using flow cytometry, we showed that addition of antimicrobial agents prior to sampling did not kill all bacteria (Kuijken et al. 2010, unpublished). Net exudation is what drives the energy conversion in the Plant-MFC. The objective of this study is to develop a simple procedure to estimate net root exudation by quantifying concentration and breakdown of common exudates in our hydroponic root system.