Aerobic biodegradation of high explosive hexahydro-1,3,5- trinitro-1,3,5-triazine by Janibacter cremeus isolated from co
- PDF / 991,741 Bytes
- 9 Pages / 547.087 x 737.008 pts Page_size
- 102 Downloads / 164 Views
(0123456789().,-volV) ( 01234567 89().,-volV)
ORIGINAL RESEARCH PAPER
Aerobic biodegradation of high explosive hexahydro-1,3,5trinitro-1,3,5-triazine by Janibacter cremeus isolated from contaminated soil Anchita Kalsi . S. Mary Celin
. Jai Gopal Sharma
Received: 28 January 2020 / Accepted: 16 June 2020 Ó Springer Nature B.V. 2020
Abstract Objective To evaluate the ability of Janibacter cremeus a soil bacterium isolated from explosive contaminated site in degradation of hexahydro-1,3,5trinitro-1,3,5-triazine (RDX) and to study enzyme responsible for degradation. Results The isolate exhibited 88% degradation of RDX in 30 days of incubation. The biodegradation process followed the first order kinetics. The half- life of RDX was calculated to be 11.088 days. The RDX degradation process was complemented by concomitant release of nitrite ions with 0.78 mol of nitrite released per mole of RDX. The metabolites; Trinitroso- RDX, diamino-RDX, trimino-RDX, bis- (hydroxymethyl) nitramine and methylenedintramine derivative, viz, methylene- N- (hydroxy- methyl)hydroxylamine- N-(hydroxymethyl) nitroamine corresponding to the molecular weights 174, 162, 132, 122 and 167 Da respectively were also detected.
Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10529-020-02946-6) contains supplementary material, which is available to authorized users. A. Kalsi S. M. Celin (&) Centre for Fire Explosives and Environment Safety (CFEES), DRDO, Delhi, India e-mail: [email protected] A. Kalsi J. G. Sharma Delhi Technological University, Delhi, India
Nitroreductase enzyme was found to be responsible for RDX degradation. Conclusion J. cremeus could degrade RDX as sole source of nitrogen, via three different pathways wherein, Nitroreductase enzyme was found to play a major role. The efficient degradation of RDX makes J. cremeus suitable in treatment of contaminated water and soil at field scale levels. Keywords Bioremediation Degradation pathway Explosives Nitroreductase enzyme List of symbols ln Natural logarithm k Rate constant
Introduction Explosives are toxic compounds predominantly found in the military areas. High explosive, Hexahydro1,3,5- trinitro-1,3,5-triazine (RDX) is one of the most commonly used military explosive. It’s a heterocyclic nitramine compound which finds its way into the soil and water generally through improper disposal of manufacturing and process waste, loading, assembly, packaging (LAP) and testing (Oh et al. 2003). RDX has been classified as a potential human carcinogen by United States Environment Protection Agency (USEPA 2011) based on animal studies. Because of
123
Biotechnol Lett
its detrimental effects, the treatment of RDX contaminated waters is of utmost importance. Many physical methods such as adsorption, ozonation, exposure to ultraviolet radiation (UV) and chemical methods such as alkaline/ acid hydrolysis, catalyst mediated and advanced oxidation processes have been developed for the treatment of contaminated waters. But, these approa
Data Loading...
