Pojanakorn Charathirakup and Alissara Reungsang

pp. 853 - 860

Abstract

Three Methyl Tertiary Butyl Ether (MTBE) degradative consortia were isolated from gasoline-contaminated soil namely: mKMS, mKGS1 and mKGS2. These consortia were tested for the ability to degrade Ethyl Tertiary Butyl Ether (ETBE) at the concentration of 100 mg/L and to degrade a mixture of MTBE
and ETBE in the Nutrient Broth (NB) media at the concentration of 50 mg/L each. The results showed that mKGS1 was the best degraders in which 74% of MTBE, 25% of ETBE and 16% of MTBE and 23% of ETBE in the mixture were degraded, within 30 days. mKGS1 was then further used in the bioaugmentation
and biostimulation experiments. Degradation of MTBE increased from 34% to 61% after 70 days when mKGS1 was amended in soil mixed with the combination of MTBE and ETBE (at 50 mg/L each). However, mKGS1 did not significantly help the ETBE degradation when it was amended in soil (biostimulation
technique). One percent glucose significantly stimulated the degradation of MTBE by the indigenous microorganisms. The presence of mKGS1 and an addition of 1% glucose as extra carbon source improved the degradation of MTBE, from 42 to 51%, suggesting mKGS1 played an important role in the degradation of MTBE.