Endosulfan Mineralization by Bacterial Isolates and Possible Degradation Pathway Identification
TL;DR: From the present investigation, it was postulated that endosulfan was mineralized via hydrolysis pathway with the formation of carbenium ions and/or ethylcarboxylates, which later converted into simple hydrocarbons.
Abstract: A bacterial consortium consists of three bacterial isolates, which rapidly mineralizes endosulfan, was enriched from an endosulfan-processing industrial surface soil. Batch experiments were conducted using bacterial consortium and its pure isolates for their potential degradation of endosulfan and its metabolites, i.e., endosulfan sulfate, endosulfan ether, and endosulfan lactone, in anaerobic condition. Endosulfan degradation was promising with bacterial consortium and pure isolates. Staphylococcus sp. preferably utilized beta endosulfan whereas other two Bacillus strains utilized more alpha endosulfan. The addition of supplementary carbon, i.e., dextrose, stimulated the endosulfan degradation efficiency in both the cases. Degradation of endosulfan ether and endosulfan lactone was promising with Bacillus circulans I and II whereas no endosulfan sulfate was degraded by any of these strains. From the present investigation, it was postulated that endosulfan was mineralized via hydrolysis pathway wi...
Citations
More filters
TL;DR: In this article, the authors have attempted to discuss the recent challenge of pesticide problem in soil environment and their biodegradation with the help of effective indigenous pesticides degrading microorganisms and highlighted and explored the molecular mechanism for the pesticide degradation in soil with effective indigenous microbial consortium.
Abstract: The extensive use of pesticide causes imbalance in properties of soil, water and air environments due to having problem of natural degradation. Such chemicals create diverse environmental problem via biomagnifications. Currently, microbial degradation is one of the important techniques for amputation and degradation of pesticide from agricultural soils. Some studies have reported that the genetically modified microorganism has ability to degrade specific pesticide but problem is that they cannot introduce in the field because they cause some other environmental problems. Only combined microbial consortia of indigenous and naturally occurring microbes isolated from particular contaminated environment have ability to degrade pesticides at faster rate. The bioaugumentation processes like addition of necessary nutrients or organic matter are required to speed up the rate of degradation of a contaminant by the indigenous microbes. The use of indigenous microbial strains having plant growth activities is ecologically superior over the chemical methods. In this review, we have attempted to discuss the recent challenge of pesticide problem in soil environment and their biodegradation with the help of effective indigenous pesticides degrading microorganisms. Further, we highlighted and explored the molecular mechanism for the pesticide degradation in soil with effective indigenous microbial consortium. This review suggests that the use of pesticide degrading microbial consortia which is an eco-friendly technology may be suitable for the sustainable agriculture production.
187 citations
TL;DR: Gene encoding for enzyme has been identified for several pesticides, which will provide a new inputs in understanding the microbial capability to degrade a pesticide and develop a super strain to achieve the desired result of bioremediation in a short time.
Abstract: Biodegradation is a natural process, where the degradation of a xenobiotic chemical or pesticide by an organism is primarily a strategy for their own survival. Most of these microbes work in natural environment but some modifications can be brought about to encourage the organisms to degrade the pesticide at a faster rate in a limited time frame. This capability of microbe is some times utilized as technology for removal of contaminant from actual site. Knowledge of physiology, biochemistry and genetics of the desired microbe may further enhance the microbial process to achieve bioremediation with precision and with limited or no scope for uncertainty and variability in microbe functioning. Gene encoding for enzyme has been identified for several pesticides, which will provide a new inputs in understanding the microbial capability to degrade a pesticide and develop a super strain to achieve the desired result of bioremediation in a short time.
164 citations
Cites background from "Endosulfan Mineralization by Bacter..."
...Endosulfan ether was reported to be converted to endosulfan lactone and some other intermediate compounds [7]....
[...]
TL;DR: The metabolizing potential of a bacterial strain Rhodococcus MTCC 6716, isolated from the gut of an Indian earthworm, may be utilized for bioremediation of endosulfan.
Abstract: The metabolizing potential of a bacterial strain Rhodococcus MTCC 6716, isolated from the gut of an Indian earthworm (Metaphire posthuma) was studied for endosulfan bioremediation. In the present work, the optimum conditions for the maximum growth, kinetic of endosulfan degradation, regression equation, half life and correlation coefficient were studied. Endosulfan induced alterations in the expression of mRNA and protein of specific endosulfan metabolizing marker gene (Esd) was studied. Maximum growth of bacteria was observed at pH 7.0, 30°C and 0.085 M sodium chloride concentration in a liquid culture medium. Endosulfan was degraded by Rhodococcus strain up to 97.23% within 15 days without producing toxic metabolite and with strong correlation coefficient (-0.728) and half life 5.99 days. Endosulfan degradation was mediated through gene(s) present in genomic DNA. Expression of marker gene was found endosulfan concentration dependent. The results suggest that this novel strain (Rhodococcus) may be utilized for bioremediation of endosulfan.
44 citations
TL;DR: The result indicates the potential capability of these microorganisms in complete mineralization of endosulfan and pendimethalin and based on half-lives, the efficiency of bacterial strains can be ordered as follows: B. safensis for endos sulfuran and B. subtilis for pendIMethalin.
Abstract: Biodegradation of endosulfan (α and β) and pendimethalin by Bacillus safensis strain FO-36bT, Bacillus subtilis subsp. inaquosorum strain KCTC 13429T and Bacillus cereus strain ATCC14579T isolated from pesticides-polluted soil was studied in mineral salt medium. Endosulfan and pendimethalin were incubated with the three bacterial strains with samples drawn at various intervals for GC analysis. Representative samples were subject to GC–MS analysis. The loss in the initial concentrations, 0.663 mM (α endosulfan), 0.319 mM (β endosulfan) and 1.423 mM (pendimethalin), was monitored and used to compute the half-lives following biphasic model. Removal percentage of endosulfan and pendimethalin in the media inoculated with the bacterial strains ranged from 24 to 95% (α endosulfan), 21–91% (β endosulfan) and 51–97% (pendimethalin), respectively. Despite the significant decrease in starting material in B. safensis cultures, no metabolites were detected, whereas two major metabolites of endosulfan, 1,2,3,4,7,7-hexachloro-5,6-dihydroxybicyclo{2.2.1}-2-heptene and 1,2,3,4,7,7-hexachloro-formaldehyde-6-methylbicyclo{2.2.1}-2-heptene, were detected in the B. subtilis cultures, and one metabolite of pendimethalin metabolite; N-(1-ethylpropyl)-3-methyl-2, 6-diaminobenzine, was detected in the B. cereus culture. Generally, the result indicates the potential capability of these microorganisms in complete mineralization of endosulfan and pendimethalin. Based on half-lives, the efficiency of bacterial strains can be ordered as follows: B. subtilis > B. cereus > B. safensis for endosulfan and B. cereus > B. safensis > B. subtilis for pendimethalin.
37 citations
Cites background from "Endosulfan Mineralization by Bacter..."
..., Bacillus circulans, Klebsiella oxytoca [17, 25, 26], Bacillus megaterium, Pseudomonas sp, Pyricularia sp, Rhizobium sp, Trichoderma viride aeruginosa, Bacillus mycoides, Bacillus cereus and Agrobacterium tumefaciens [27–30]....
[...]
TL;DR: The results suggest that the Penicillium sp.
Abstract: Endosulfan is an organochloride and persistent pesticide that has caused concern because of its impact in the environment and its toxicity to and bioaccumulation in living organisms. In this study, we isolated an endosulfan-degrading fungus from the activated sludge from an industrial wastewater treatment plant. Through repetitive enrichment and successive subculture in media containing endosulfan as the sole carbon source, a fungus designated CHE 23 was isolated. Based on a phylogenetic analysis, strain CHE 23 was assigned to the genus Penicillium sp. In a mineral salt medium with 50 mg/l endosulfan as the sole source carbon, CHE 23 removed the added endosulfan in a period of six days. To verify the decrease in endosulfan toxicity due to the activity of the fungus, we performed genotoxicity tests trough the single cell gel electrophoresis assay or comet assay, with Eisenia fetida as the bioindicator species. This organism was exposed to the supernatants of the culture of the fungus and endosulfan. Our results indicated that the genotoxicity of endosulfan was completely reduced due the activity of this fungus. These results suggest that the Penicillium sp. CHE 23 strain can be used to degrade endosulfan residues and/or for water and soil bioremediation processes without causing toxicity problems, which are probably due to the generation of no-toxic metabolites during biodegradation.
31 citations
Cites methods from "Endosulfan Mineralization by Bacter..."
...An advantage of these methods is that endosulfan can be used as the sole source of carbon and/or sulfur during the biodegradation process (Kumar and Philip 2006; Sutherland et al. 2000; Guerin 1999)....
[...]
References
More filters
TL;DR: Pesticides used in Portuguese agricultural areas have been found in surface and ground waters and the use of multiresidue methods and automated techniques are desirable in future work.
Abstract: Pesticides used in Portuguese agricultural areas have been found in surface and ground waters. In the surface water collected in three river basins from 1983 to 1999, insecticides and herbicides were detected from the monitored pesticides, particularly atrazine, chlorfenvinphos (Z+E), alpha- and beta-endosulfan, lindane, molinate and simazine, reaching the maximum values, respectively, of 0.63, 31.6, 0.18 microg/L (alpha-endosulfan), 0.18 microg/L (beta-endosulfan), 0.24, 48 and 0.3 microg/L. In the ground water collected from the wells of seven agricultural areas from 1991 to 1998, several monitored herbicides were detected: alachlor, atrazine, metolachlor, metribuzine and simazine, reaching the maximum concentration values of 13, 30, 56, 1.4 and 0.4 microg/L, respectively. The herbicides more frequently detected were atrazine (64%), simazine (45%) and alachlor (25%). Other than these, the monitored pesticides can be present in Portuguese surface and ground waters. Therefore, to improve the analytical conditions, the use of multiresidue methods and automated techniques are desirable in future work.
432 citations
"Endosulfan Mineralization by Bacter..." refers background in this paper
...Endosulfan is ubiquitous and environmentally persistent, as a result the presence of endosulfan residues were traced in surface water, groundwater, atmosphere, and water bodies by many researchers (Sujatha et al., 1999; Bhattacharya et al., 2002; Berrakat et al., 2002; Cerejeira et al., 2003; Golfinopoulos et al., 2003)....
[...]
...…and environmentally persistent, as a result the presence of endosulfan residues were traced in surface water, groundwater, atmosphere, and water bodies by many researchers (Sujatha et al., 1999; Bhattacharya et al., 2002; Berrakat et al., 2002; Cerejeira et al., 2003; Golfinopoulos et al., 2003)....
[...]
TL;DR: It is concluded that metabolism of this compound does not involve the action of extracellular peroxidases, and it is suggested that the metabolism of endosulfan is mediated by two divergent pathways, one hydrolytic and the other oxidative.
Abstract: Recent studies have shown that cultures of white rot fungi not favoring the production of lignin and manganese peroxidases are effective in degrading certain xenobiotics In this study we have used endosulfan as a model xenobiotic to assess the enzymatic mechanisms of pesticide metabolism under ligninolytic (nutrient-deficient) and nonligninolytic (nutrient-rich) culture conditions Rapid metabolism of this chlorinated pesticide occurred under each nutrient condition tested However, the extent of degradation and the nature of the metabolic products differed for nutrient-deficient and nutrient-rich media The pathways for endosulfan metabolism were characterized by analysis of the fungal metabolites produced The major endosulfan metabolites were identified by gas chromatography-electron capture detection and gas chromatography-mass spectrometry as endosulfan sulfate, endosulfan diol, endosulfan hydroxyether, and a unknown metabolite tentatively identified as endosulfan dialdehyde The nature of the metabolites formed indicates that this organism utilizes both oxidative and hydrolytic pathways for metabolism of this pesticide Piperonyl butoxide, a known cytochrome P-450 inhibitor, significantly inhibited the oxidation of endosulfan to endosulfan sulfate and enhanced hydrolysis of endosulfan to endosulfan diol We suggest that the metabolism of endosulfan is mediated by two divergent pathways, one hydrolytic and the other oxidative Judging by the inactivity of extracellular fluid and partially purified lignin peroxidase in metabolizing endosulfan, we conclude that metabolism of this compound does not involve the action of extracellular peroxidases
236 citations
"Endosulfan Mineralization by Bacter..." refers background or methods in this paper
...…described the biodegradation of endosulfan under aerobic and anaerobic conditions with bacterial and fungal cultures (Katayama and Matsumura, 1993; Mukherjee and Gopal, 1994; Kullman and Matsumura, 1996; Awasthi et al., 1997; Shetty et al., 2000; Sutherland et al., 2000; Siddique et al., 2003)....
[...]
...The mass spectra of the samples are shown in Figure 5a to 5c. Kullman and Matsumura (1996), Sutherland et al. (2002a), and Weir et al. (2006) conducted the endosulfan degradation experiments with white rot fungi and bacterial isolate, respectively....
[...]
TL;DR: A microbial consortium which rapidly mineralized the environmentally persistent pollutant benzo[a]pyrene was recovered from soil and revealed that eight of the consortium members were related to the classProteobacteria but that the consortium also included members which were relatedto the genera Mycobacterium andSphingobacteria.
Abstract: A microbial consortium which rapidly mineralized the environmentally persistent pollutant benzo[a]pyrene was recovered from soil. The consortium cometabolically converted [7-14C]benzo[a]pyrene to 14CO2 when it was grown on diesel fuel, and the extent of benzo[a]pyrene mineralization was dependent on both diesel fuel and benzo[a]pyrene concentrations. Addition of diesel fuel at concentrations ranging from 0.007 to 0.2% (wt/vol) stimulated the mineralization of 10 mg of benzo[a]pyrene per liter 33 to 65% during a 2-week incubation period. When the benzo[a]pyrene concentration was 10 to 100 mg liter−1 and the diesel fuel concentration was 0.1% (wt/vol), an inoculum containing 1 mg of cell protein per liter (small inoculum) resulted in mineralization of up to 17.2 mg of benzo[a]pyrene per liter in 16 days. This corresponded to 35% of the added radiolabel when the concentration of benzo[a]pyrene was 50 mg liter−1. A radiocarbon mass balance analysis recovered 25% of the added benzo[a]pyrene solubilized in the culture suspension prior to mineralization. Populations growing on diesel fuel most likely promoted emulsification of benzo[a]pyrene through the production of surface-active compounds. The consortium was also analyzed by PCR-denaturing gradient gel electrophoresis of 16S rRNA gene fragments, and 12 dominant bands, representing different sequence types, were detected during a 19-day incubation period. The onset of benzo[a]pyrene mineralization was compared to changes in the consortium community structure and was found to correlate with the emergence of at least four sequence types. DNA from 10 sequence types were successfully purified and sequenced, and that data revealed that eight of the consortium members were related to the class Proteobacteria but that the consortium also included members which were related to the genera Mycobacterium and Sphingobacterium.
182 citations
"Endosulfan Mineralization by Bacter..." refers background in this paper
...Kanaly et al. (2000) reported that benzo[a]pyrene was transferred initially into culture suspension and was degraded by cometabolism ultimately resulting in mineralization....
[...]
...Kanaly et al. (2000) reported that benzo[a]pyrene was transferred initially into culture suspension and was degraded by cometabolism ultimately resulting in mineralization....
[...]
TL;DR: The results suggest that this mixed culture is worth investigating as a source of endosulfan-hydrolyzing enzymes for use in enzymatic bioremediation of endOSulfan residues.
Abstract: An endosulfan-degrading mixed bacterial culture was enriched from soil with a history of endosulfan exposure. Enrichment was obtained by using the insecticide as the sole source of sulfur. Chemical hydrolysis was minimized by using strongly buffered culture medium (pH 6.6), and the detergent Tween 80 was included to emulsify the insecticide, thereby increasing the amount of endosulfan in contact with the bacteria. No growth occurred in control cultures in the absence of endosulfan. Degradation of the insecticide occurred concomitant with bacterial growth. The compound was both oxidized and hydrolyzed. The oxidation reaction favored the alpha isomer and produced endosulfate, a terminal pathway product. Hydrolysis involved a novel intermediate, tentatively identified as endosulfan monoaldehyde on the basis of gas chromatography-mass spectrometry and chemical derivatization results. The accumulation and decline of metabolites suggest that the parent compound was hydrolyzed to the putative monoaldehyde, thereby releasing the sulfite moiety required for growth. The monoaldehyde was then oxidized to endosulfan hydroxyether and further metabolized to (a) polar product(s). The cytochrome P450 inhibitor, piperonyl butoxide, did not prevent endosulfan oxidation or the formation of other metabolites. These results suggest that this mixed culture is worth investigating as a source of endosulfan-hydrolyzing enzymes for use in enzymatic bioremediation of endosulfan residues.
177 citations
"Endosulfan Mineralization by Bacter..." refers background in this paper
...Endosulfan can be utilized as a sole source of carbon and/or sulfur during biodegradation (Guerin, 1999; Sutherland et al., 2000)....
[...]
...Several researchers described the biodegradation of endosulfan under aerobic and anaerobic conditions with bacterial and fungal cultures (Katayama and Matsumura, 1993; Mukherjee and Gopal, 1994; Kullman and Matsumura, 1996; Awasthi et al., 1997; Shetty et al., 2000; Sutherland et al., 2000; Siddique et al., 2003)....
[...]
...Endosulfan can be degraded by attacking the sulfide group by oxidation and/or hydrolysis to form the toxic metabolite endosulfan sulfate and the less toxic endosulfan diol, respectively (Sutherland et al., 2000)....
[...]
...In addition, endosulfan degradation was more successful with consortium of bacterial strains compared to bacterial isolates (Awasthi et al., 1997; Sutherland et al., 2000)....
[...]
...…described the biodegradation of endosulfan under aerobic and anaerobic conditions with bacterial and fungal cultures (Katayama and Matsumura, 1993; Mukherjee and Gopal, 1994; Kullman and Matsumura, 1996; Awasthi et al., 1997; Shetty et al., 2000; Sutherland et al., 2000; Siddique et al., 2003)....
[...]
TL;DR: The contamination levels of PCBs, total DDTs and total chlordane were in high range compared to other locations worldwide and sites that were contaminated with high concentrations of organochlorine compounds were associated with dense population and low energy environment.
Abstract: Persistent organochlorine compound concentrations were determined for 23 surface sediment samples collected from Alexandria Harbor, Egypt. Total PCB concentrations ranged from 0.9 to 1210 ng/g with four to seven Cl-substituted biphenyls being the most prevalent PCBs congeners. Different PCB congener distribution patterns were observed, probably reflecting different inputs and attenuation at various locations. Total DDT concentrations varied from
168 citations
"Endosulfan Mineralization by Bacter..." refers background in this paper
...Endosulfan is ubiquitous and environmentally persistent, as a result the presence of endosulfan residues were traced in surface water, groundwater, atmosphere, and water bodies by many researchers (Sujatha et al., 1999; Bhattacharya et al., 2002; Berrakat et al., 2002; Cerejeira et al., 2003; Golfinopoulos et al., 2003)....
[...]