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Updated: Jul 3, 2026
08:13
A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Biological breakdown of RDX in slurry reactors proceeds with multiple kinetically distinguishable paths
D M Young1, C L Kitts, P J Unkefer
1Department of Chemical and Environmental Engineering, University of Arizona, Tucson, Arizona, USA.
Biotechnology and Bioengineering
|July 19, 2008
Summary
Corn steep liquor effectively supports the cometabolic biotransformation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Bioremediation of RDX-contaminated soil is a viable cleanup option using this method.
Area of Science:
- Environmental microbiology
- Bioremediation technologies
- Chemical engineering
Background:
- Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a persistent explosive contaminant.
- Bioremediation using microbial communities offers a sustainable cleanup approach.
- Understanding nutrient requirements is crucial for optimizing RDX biotransformation.
Purpose of the Study:
- To evaluate the necessity of supplementing known biodegraders for RDX biotransformation.
- To identify effective nutrient sources for enhancing RDX cometabolism.
- To assess the feasibility of RDX bioremediation in slurry reactors.
Main Methods:
- Slurry reactor experiments were conducted to study RDX biotransformation.
- The impact of bacterial addition and nutrient sources (corn steep liquor) was investigated.
- Kinetics of RDX transformation were analyzed, identifying distinct phases.
Main Results:
- Corn steep liquor, an inexpensive nutrient source, facilitated RDX cometabolic biotransformation.
- While bacterial addition increased rates, it may not be cost-effective.
- RDX biotransformation exhibited three kinetically distinct phases and was reaction rate-limited.
- Model simulations indicated bioremediation is attractive at 5 g/L cell densities.
Conclusions:
- Corn steep liquor is a suitable and economical nutrient source for RDX bioremediation.
- Bioremediation of RDX-contaminated soil is a promising and potentially cost-effective cleanup alternative.
- Optimizing nutrient supply is key to enhancing the efficiency of RDX biotransformation in slurry systems.
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