Isolation and Screening of Acetochlor-Degrading Strain and its Degradation Characteristics

The acetochlor residue in the tobacco cultivated soils was inclined to affect the growth of tobacco. In this study, regarding the acetochlor as the inorganic salt medium with the sole carbon source, we obtain the acetochlor-degrading bacteria from the tobacco cultivated soil through isolation and screening, numbering as CSUFTM78. Under the view of the microscopy, the bacteria has a rod shape and no spore with the size of 0.8 ~ 1.5 × 0.4 ~ 0.6μm; in the medium, the colonies are opaque, white, round, convex with neat edge and moist and shiny surface. Then determine the concentration of acetochlor which was directly added into the liquid medium and the phote-absorbance of strain number using UV spectrophotometer. The results indicate that the strain CSUFTM78 can grow in the inorganic salt medium which regards quinclorac as the sole carbon source; besides, the degradation rate was up to 38%. By determining the 16S sequence of CSUFTM78 strain, the homology of GENBANK in BLAST reaches more than 99% with Stenotrophomonas maltophilia (HQ185399). By constructing a phylogenetic tree, strain CSUFTM78 and S. maltophilia were integrated into one with the confidence of 100%. Combined with the morphological characteristics of strains, we identify the CSUFTM78 as S.maltophilia and the results can provide both strains and theoretical basis for degrading the acetochlor residual in tobacco cultivated soil using microorganism.

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Research on the Degradation of Herbicide-Quinclorac by Microorganism

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.739.349 ◽

2013 ◽

Vol 739 ◽

pp. 349-354 ◽

Cited By ~ 2

Author(s):

Xiong Zhi Zheng ◽

Wei Ai Zeng ◽

Song Yi Zhao ◽

Yan Ning Huang ◽

Qing Ming Zhou

Keyword(s):

Bacterial Strain ◽

Stenotrophomonas Maltophilia ◽

Degradation Rate ◽

Morphological Characteristics ◽

Degradation Temperature ◽

Degrading Bacteria ◽

Optimum Ph ◽

Different Temperatures ◽

16S Sequence ◽

Degradation Effect

In order to study the degradation of herbicide----Quinclorac using microorganism, separate and screen the degrading bacteria CSUFTM62 from soil, this paper researched the degradation effect of bacterial strain on the Quinclorac under different situations, including different increments, different temperatures, different concentrations of pesticide, different pH, and different additive amount of nutrients. The results show that the optimal degradation temperature is 30 ° C; the optimum pH is 7; the degradation rate of Quinclorac reaches its maximum when the concentration is 50mg / L. Adding yeast extract could increase the amount of strain growth but never affect its degradation effects on Quinclorac; combined with the morphological characteristics, the strains CSUFTM62 is identified as the Stenotrophomonas maltophilia by measuring the 16S sequence.

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Isolation and Characterization of a Styrene Trimer Degrading Microorganism

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1073-1076.666 ◽

2014 ◽

Vol 1073-1076 ◽

pp. 666-671

Author(s):

Guang Chun Li ◽

Chun Xiang Piao ◽

Katsuhiko Saido ◽

Seon Yong Chung

Keyword(s):

Pseudomonas Aeruginosa ◽

Liquid Phase ◽

Carbon Source ◽

Sole Carbon Source ◽

Isolation And Characterization ◽

Degrading Bacteria ◽

Ochrobactrum Intermedium ◽

Complex Strain ◽

Degrading Microorganism

Biodegradation of the styrene trimer was investigated, and its degrading bacteria were screened and isolated. Complex bacteria ST (strain ST1 and ST2) was isolated from contaminated soil by polystyrene and named by strain ST1 and ST2. ST1 and ST2 were identified by 16S rDNA and classified byOchrobactrum intermediumsp. andPseudomonas aeruginosasp., respectively. Biodegradation experiments were performed in batch and styrene trimer was used as a sole carbon source. Isolated two bacteria were used as degrading microorganisms. Initial liquid phase concentration of the styrene trimer was 50 mg/L. 95% of the styrene trimer was degraded in 17 days by the complex strain ST. The concentration was analyzed by using GC. Metabolites of bacteria were analyzed and three kinds of products that were identified by GC/MS.

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Isolation and Characterization of Biosurfactant-producing Alcaligenes sp. YLA11 and its Diesel Degradation Potentials

Bioremediation Science and Technology Research ◽

10.54987/bstr.v9i2.619 ◽

2021 ◽

Vol 9 (2) ◽

pp. 7-12

Author(s):

Abdulrahman Abdulhamid Arabo ◽

Raji Arabi Bamanga ◽

Mujiburrahman Fadilu ◽

Musa Abubakar ◽

Fatima Abdullahi Shehu ◽

...

Keyword(s):

Carbon Source ◽

Incubation Time ◽

Sole Carbon Source ◽

Enrichment Culture ◽

Diesel Oil ◽

Contaminated Site ◽

Screening Methods ◽

Bacterial Strains ◽

Isolation And Characterization ◽

Degrading Bacteria

This study aimed to isolate and identify biosurfactant producing and diesel alkanes degrading bacteria. For this reason, bacteria isolated from the diesel contaminated site were screened for their potential to produce biosurfactants and degrade diesel alkanes. Primary selection of diesel degraders was carried out by using conventional enrichment culture technique where 12 bacterial strains were isolated based on their ability to grow on minimal media supplemented with diesel as sole carbon source, which was followed by qualitative screening methods for potential biosurfactant production. Isolate B11 was the only candidate that shows positive signs for drop collapse, foaming, haemolytic test, oil displacement of more than 22 ± 0.05 mm, and emulsification (E24) of 14 ± 0.30%. The effect of various culture parameters (incubation time, diesel concentration, nitrogen source, pH and temperature) on biodegradation of diesel was evaluated. The optimum incubation time was confirmed to be 120 days for isolates B11, the optimum PH was confirmed as 8.0 for the isolate, Similarly, the optimum temperature was confirmed as 35oC. In addition, diesel oil was used as the sole carbon source for the isolates. The favourable diesel concentration was 12.5 % (v/v) for the isolate. The isolate has shown degradative ability towards Tridecane (C13), dodecane, 2, 6, 10-trimethyl- (C15), Tetradecane (C14), 2,6,10-Trimethyltridecane (C16), Pentadecane (C15). It degraded between 0.27% - 9.65% individual diesel oil alkanes. The strain has exhibited the potential of degrading diesel oil n-alkanes and was identified as Alcaligenes species strain B11 (MZ027604) using the 16S rRNA sequencing.

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Biofilm-Mediated Enhanced Crude Oil Degradation by Newly Isolated Pseudomonas Species

ISRN Biotechnology ◽

10.5402/2013/250749 ◽

2013 ◽

Vol 2013 ◽

pp. 1-13 ◽

Cited By ~ 35

Author(s):

Debdeep Dasgupta ◽

Ritabrata Ghosh ◽

Tapas K. Sengupta

Keyword(s):

Carbon Source ◽

Crude Oil ◽

Sole Carbon Source ◽

River Estuary ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Oil Degradation ◽

Topographic Analysis ◽

Degrading Bacteria ◽

Crude Oil Degradation

The bioavailability of organic contaminants to the degrading bacteria is a major limitation to efficient bioremediation of sites contaminated with hydrophobic pollutants. Such limitation of bioavailability can be overcome by steady-state biofilm-based reactor. The aim of this study was to examine the effect of such multicellular aggregation by naturally existing oil-degrading bacteria on crude oil degradation. Microorganisms, capable of utilizing crude oil as sole carbon source, were isolated from river, estuary and sea-water samples. Biochemical and 16S rDNA analysis of the best degraders of the three sources was found to belong to the Pseudomonas species. Interestingly, one of the isolates was found to be close to Pseudomonas otitidis family which is not reported yet as a degrader of crude oil. Biodegradation of crude oil was estimated by gas chromatography, and biofilm formation near oil-water interface was quantified by confocal laser scanning microscopy. Biofilm supported batches of the isolated Pseudomonas species were able to degrade crude oil much readily and extensively than the planktonic counterparts. Volumetric and topographic analysis revealed that biofilms formed in presence of crude oil accumulate higher biomass with greater thickness compared to the biofilms produced in presence of glucose as sole carbon source.

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Styrene oxide isomerase of Sphingopyxis sp. Kp5.2

Microbiology ◽

10.1099/mic.0.080259-0 ◽

2014 ◽

Vol 160 (11) ◽

pp. 2481-2491 ◽

Cited By ~ 26

Author(s):

Michel Oelschlägel ◽

Juliane Zimmerling ◽

Michael Schlömann ◽

Dirk Tischler

Keyword(s):

Carbon Source ◽

Sole Carbon Source ◽

Styrene Oxide ◽

Gene Clusters ◽

16S Rrna Genes ◽

Rrna Genes ◽

Side Chain ◽

Biotechnological Production ◽

Chain Oxidation ◽

Degrading Bacteria

Styrene oxide isomerase (SOI) catalyses the isomerization of styrene oxide to phenylacetaldehyde. The enzyme is involved in the aerobic styrene catabolism via side-chain oxidation and allows the biotechnological production of flavours. Here, we reported the isolation of new styrene-degrading bacteria that allowed us to identify novel SOIs. Out of an initial pool of 87 strains potentially utilizing styrene as the sole carbon source, just 14 were found to possess SOI activity. Selected strains were classified phylogenetically based on 16S rRNA genes, screened for SOI genes and styrene-catabolic gene clusters, as well as assayed for SOI production and activity. Genome sequencing allowed bioinformatic analysis of several SOI gene clusters. The isolate Sphingopyxis sp. Kp5.2 was most interesting in that regard because to our knowledge this is the first time it was shown that a member of the family Sphingomonadaceae utilized styrene as the sole carbon source by side-chain oxidation. The corresponding SOI showed a considerable activity of 3.1 U (mg protein)–1. Most importantly, a higher resistance toward product inhibition in comparison with other SOIs was determined. A phylogenetic analysis of SOIs allowed classification of these biocatalysts from various bacteria and showed the exceptional position of SOI from strain Kp5.2.

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Environmental Consortium Containing Pseudomonas and Bacillus Species Synergistically Degrades Polyethylene Terephthalate Plastic

mSphere ◽

10.1128/msphere.01151-20 ◽

2020 ◽

Vol 5 (6) ◽

pp. e01151-20

Author(s):

Cameron Roberts ◽

Sabrina Edwards ◽

Morgan Vague ◽

Rosa León-Zayas ◽

Henry Scheffer ◽

...

Keyword(s):

Carbon Source ◽

Ethylene Glycol ◽

Polyethylene Terephthalate ◽

Terephthalic Acid ◽

Sole Carbon Source ◽

Basal Medium ◽

Building Blocks ◽

Bacillus Species ◽

Bacterial Consortia ◽

Degrading Bacteria

ABSTRACTPlastics, such as polyethylene terephthalate (PET) from water bottles, are polluting our oceans, cities, and soils. While a number of Pseudomonas species have been described that degrade aliphatic polyesters, such as polyethylene (PE) and polyurethane (PUR), few from this genus that degrade the semiaromatic polymer PET have been reported. In this study, plastic-degrading bacteria were isolated from petroleum-polluted soils and screened for lipase activity that has been associated with PET degradation. Strains and consortia of bacteria were grown in a liquid carbon-free basal medium (LCFBM) with PET as the sole carbon source. We monitored several key physical and chemical properties, including bacterial growth and modification of the plastic surface, using scanning electron microscopy (SEM) and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) spectroscopy. We detected by-products of hydrolysis of PET using 1H-nuclear magnetic resonance (1H NMR) analysis, consistent with the ATR-FTIR data. The full consortium of five strains containing Pseudomonas and Bacillus species grew synergistically in the presence of PET and the cleavage product bis(2-hydroxyethyl) terephthalic acid (BHET) as sole sources of carbon. Secreted enzymes extracted from the full consortium were capable of fully converting BHET to the metabolically usable monomers terephthalic acid (TPA) and ethylene glycol. Draft genomes provided evidence for mixed enzymatic capabilities between the strains for metabolic degradation of TPA and ethylene glycol, the building blocks of PET polymers, indicating cooperation and ability to cross-feed in a limited nutrient environment with PET as the sole carbon source. The use of bacterial consortia for the biodegradation of PET may provide a partial solution to widespread planetary plastic accumulation.IMPORTANCE While several research groups are utilizing purified enzymes to break down postconsumer PET to the monomers TPA and ethylene glycol to produce new PET products, here, we present a group of five soil bacteria in culture that are able to partially degrade this polymer. To date, mixed Pseudomonas spp. and Bacillus spp. biodegradation of PET has not been described, and this work highlights the possibility of using bacterial consortia to biodegrade or potentially to biorecycle PET plastic waste.

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Low-Density Polyethylene Film Biodegradation Potential by Fungal Species from Thailand

Journal of Fungi ◽

10.3390/jof7080594 ◽

2021 ◽

Vol 7 (8) ◽

pp. 594

Author(s):

Sarunpron Khruengsai ◽

Teerapong Sripahco ◽

Patcharee Pripdeevech

Keyword(s):

Carbon Source ◽

Sole Carbon Source ◽

Mineral Salt Medium ◽

Plastic Waste ◽

Mineral Salt ◽

Alternative Methods ◽

Low Density Polyethylene ◽

Low Density ◽

Salt Medium ◽

Ldpe Film

Accumulated plastic waste in the environment is a serious problem that poses an ecological threat. Plastic waste has been reduced by initiating and applying different alternative methods from several perspectives, including fungal treatment. Biodegradation of 30 fungi from Thailand were screened in mineral salt medium agar containing low-density polyethylene (LDPE) films. Diaporthe italiana, Thyrostroma jaczewskii, Collectotrichum fructicola, and Stagonosporopsis citrulli were found to grow significantly by culturing with LDPE film as the only sole carbon source compared to those obtained from Aspergillus niger. These fungi were further cultured in mineral salt medium broth containing LDPE film as the sole carbon source for 90 days. The biodegradation ability of these fungi was evaluated from the amount of CO2 and enzyme production. Different amounts of CO2 were released from D. italiana, T. jaczewskii, C. fructicola, S. citrulli, and A. niger culturing with LDPE film, ranging from 0.45 to 1.45, 0.36 to 1.22, 0.45 to 1.45, 0.33 to 1.26, and 0.37 to 1.27 g/L, respectively. These fungi were able to secrete a large amount of laccase enzyme compared to manganese peroxidase, and lignin peroxidase enzymes detected under the same conditions. The degradation of LDPE films by culturing with these fungi was further determined. LDPE films cultured with D. italiana, T. jaczewskii, C. fructicola, S. citrulli, and A. niger showed weight loss of 43.90%, 46.34%, 48.78%, 45.12%, and 28.78%, respectively. The tensile strength of LDPE films cultured with D. italiana, T. jaczewskii, C. fructicola, S. citrulli, and A. niger also reduced significantly by 1.56, 1.78, 0.43, 1.86, and 3.34 MPa, respectively. The results from Fourier transform infrared spectroscopy (FTIR) reveal an increasing carbonyl index in LDPE films culturing with these fungi, especially C. fructicola. Analysis of LDPE films using scanning electron microscopy (SEM) confirmed the biodegradation by the presence of morphological changes such as cracks, scions, and holes on the surface of the film. The volatile organic compounds (VOCs) emitted from LDPE films cultured with these fungi were analyzed by gas chromatography-mass spectrometry (GC-MS). VOCs such as 1,3-dimethoxy-benzene, 1,3-dimethoxy-5-(1-methylethyl)-benzene, and 1,1-dimethoxy-decane were detected among these fungi. Overall, these fungi have the ability to break down and consume the LDPE film. The fungus C. fructicola is a promising resource for the biodegradation of LDPE which may be further applied in plastic degradation systems based on fungi.

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