Abstract:
The efficacy of ethyl 3-ethoxybutyrate (EEB) to serve as a biofuel additive has recently been investigated. This biofuel, which can be blended with gasoline or diesel, is made from polyhydroxyalkanoates (PHA). However, PHA are currently too expensive to produce for EEB to be economically viable. To reduce the cost of PHA production, we propose a two-stage bioreactor to convert waste hay into PHA using two separate mixed microbial cultures. We found that both communities were relatively stable over the year and a half experimental period. The maximum percent PHA achieved was 10.7% and the maximum amount of biomass accumulated was 1.545 g. While this showed promise, the maximum percent PHA occurred at the beginning of the experimental period and all attempted experimental manipulations failed to improve, and many times decreased, PHA yields. Using the knowledge gained from these failures, we propose a different method to accumulate PHA in future studies.