Biodegradation of pyrene and benzo[a]pyrene in the liquid matrix and soil by a newly identified Raoultella planticola strain

Abstract

In the current study, the PL7 strain was isolated from soil and identified as Raoultella planticola based on its physiological characteristics and 16S rDNA sequence. By the 10th day, the PL7 strain degraded 52.0% of the pyrene (PYR) content and 50.8% of the benzo[a]pyrene (BaP) content in 20 mg L PYR and 10 mg L BaP in the liquid matrix. The half-life of PYR and BaP by PL7 degradation was 8.59 and 9.46 days, respectively. At pH 8.0, the degradation rates of PYR and BaP by PL7 were significantly higher at 30 °C than at 20 and 40 °C. The degradation ability of PL7 differed in red soil, paddy soil and fluvo-aquic soil; red soil produced the fastest degradation rates. The half-life of PYR and BaP by PL7 degradation in red soil was 21.7 and 11.9 days, respectively; however, without PL7 the half-life of PYR in red soil was 91.2 days. This study demonstrated the significant potential of the PL7 strain for bioremediation applications in the liquid matrix and soil contaminated by PAHs.

Characterization and application of a newly isolated pyrene-degrading bacterium, Pseudomonas monteilii

“…A 1000-mg L -1 PYR solution was prepared in acetone and kept in a brown bottle at 4°C to avoid any light exposure prior to use. Isolation of bacterial strains from soil samples and the degradation experiments were described by Ping et al (2017).…”

“…The biodegradation of PYR by strain PL5 in paddy soil was better than that in the liquid medium, which may be due to the nutrient availability and environmental conditions in paddy soil being conducive to strain growth, thereby improving the degradation capacity. In the process of degrading high molecular weight PAHs, microorganisms can secrete certain enzymes to start the degradation process that perform typical catalytic reactions (Ping et al 2014(Ping et al , 2017. According to the kinetic model (El-Mansi et al 2007), strain PL5-mediated degradation of PYR in paddy soil exhibited first-order kinetics (c = 17.372e -0.0797t , R 2 = 0.9021) in comparison with sterilized paddy soil without PL5 (c = 19.621e -0.0045t , R 2 = 0.5122).…”

“…In the list of 16 USEPA priority control PAHs, pyrene (PYR) with four ring accounts for a large proportion of PAHs in the environment (Kastner et al 1998;Ping et al 2007). Though there are several reports about the microbial PYR degradation (Arulazhagan and Vasudevan 2011;Fu et al 2014;Ping et al 2017), PYR-degrading microorganisms still need to be further isolated and studied for efficient biodegradation of PYR.…”

Analysis of viral and bacterial communities in groundwater associated with contaminated land

“…Bacteria, with (strain-level) relatives able of biodegradation, that could also be affected by viral generalists found here include, for example, Hydrocarboniphaga sp. (by BGW-34) (Burback and Perry, 1993;Chatterjee and Bourquin, 1987;Manickam et al, 2007;Mattes et al, 2010;Palleroni et al, 2004;Ping et al, 2017;Poi et al, 2018;Revathy et al, 2015;Simarro et al, 2013).…”

Complete genome sequence of Raoultella sp. strain X13, a promising cell factory for the synthesis of CdS quantum dots

“…Specific strains in this genus possess biotechnological potentials. For example, Raoultella planticola can degrade PAH (Ping et al 2017), Raoultella ornithinolytica B6 produces 2,3-Butanediol (Kim et al 2017) and Raoultella sp. SM1, a strain capable of precipitation of uranium by dissimilatory reduction, shows considerable potential in the use of remediation of heavy metal pollution (Sklodowska et al 2018).…”