(620a) Bioconversion of Biomass Using a Coculture of Thermotoga Maritima and Methanococcus Jannaschii

The bioconversion of biomass is a means to produce industrially important chemicals such as lactate, acetate, and ethanol. This project is evaluating the feasibility of using the hyperthermophiles Thermotoga maritima and Methanococcus jannaschii for this purpose. Two methods are currently being used to pre-treat the biomass in order to make it more palatable for the organisms, pyrolysis and hydrolysis. Pyrolysis involves heating biomass to high temperatures (400 to 1200 °C) under low oxygenic conditions and results in thermal depolymerization yielding a viscous organic liquid. Hydrolysis in this case involves using supercritical water to affect a similar change. In each case the resultant products are a combination of sugars including glucose as well as other compounds not yet defined. It is known that useful products such as ethanol, hydrogen, acetate and lactate can be obtained from bioconversion using T. maritima. Utilizing natural products to replace a portion of the petroleum based chemicals may help to alleviate some of the stress the chemical process industry places on the environment. It could also potentially be an economic boost for states that are heavily based in agriculture and a means to decrease the need of government subsidies as well as working towards the Department of Energy's Vision 2020 Statement. Previous studies have relied solely on T. maritima. More recent research has shown that alleviation of inhibitory hydrogen is important to increased fermentation activity. M. jannaschii requires hydrogen for growth and when cocultured allows for a large increase in cell density for T. maritima and in theory an increase in bioconversion. Currently the work is being done in batch cultures, but there are future plans to scale up to a continuous culture system. An important step here is to gain a more complete analysis of the pyrolysis and hydrolysis mixture compositions and of the products generated upon extremophilic conversion. The majority of this work will be accomplished using HPLC analysis. This research will lead to the development a hybrid thermochemical and extremophile bioconversion process for the production of high value products from agricultural wastes.