Biostimulation and Bioaugmentation of Diesel Contaminated Environment (Soil)

Abstract

Contamination of soils with diesel hydrocarbons has always been an important worldwide issue. Among all the available remediationmethods, bioremediation is widely considered to be a cost-effective and environmentally friendly approach. For bioremediationto be effective, the overall rate of intrinsic biodegradation and subsequent removal of hydrocarbons must be accelerated,which can be done through biostimulation and bioaugmentation. Spillage of hydrocarbons is also a source of contamination for soil and water ecosystem. It provides efficacy, safety on long term use, cost and simplicity of administration with promising opportunity for creating better environment. The goal of our study was to check the diesel degradation potential at low temperature. We conducted our experiments on a carbon free medium and only carbon source provided was the diesel(5%). Microbes (bacteria in our study) utilized diesel as a sole carbon source and degraded it. A set of follow up experiments were conducted to check the diesel degrading potential of the potent isolates. Experiments at 15⁰C and 30⁰C were performed and biomass and biosurfactant activity was monitored. Microbial activity was highest at seventh day of incubation i.e 0.2521mg/ml and 0.1509 mg/ml, resecptively at both the temperature. Biosurfactant activity and biomas activity was observed higher at 30⁰C as compared with 15⁰C.But these results showed that the isolate was able to grow at low temperature and consumed 83.45% of diesel at 15⁰C as compared to 93.58% at 30⁰C. A set of experiments was also performed at extreme pH conditions(4, 5, 10 and 11) with 5% diesel and the bacterial isolate was found to be alkaliphile. BTEX degradation potential was also measured but the selected bacterial isolate was not able to grow on aromatic compounds. Various Biochemical tests were performed of the isolates which gave indications of isolate belonging to Acinetobactergenus.