Screening and optimization of arsenic degrading bacteria and their potential role in heavy metal bioremediation

Industrialization has added extremely toxic metalloid arsenic into the environment which at high concentration severely threatens the biota. Naturally, some microbes possess the ability to bio-accumulate metals and also to transform arsenite (As III) a toxic form to a non-toxic arsenate As V. The present study aimed to isolate arsenic resistant bacterias from the arsenic contaminated soil and water. Among eleven bacterial isolates, three FAs 1, 4 and 9 exhibited tolerance against sodium arsenite at 100mM concentration by achieving growth of 7.48×109,1.57×109 and 2.23×109 C.F.U./ml, respectively. Optimization at different conditions such as temperature, pH and arsenic concentration revealed high arsenic tolerance from isolate FAs 4 (5.33×108) at 37°C and FAs 1 (4.43×108 C.F.U./ml) at pH 7. Arsenic resistance at optimum conditions for the bacterial strains FAs 1, FAs 4 and FAs 9 showed maximum growth at 80mM concentration of arsenite. These bacterial isolates did not show redox ability to oxidize arsenite As III to arsenate As V. However bacterial isolates FAs 1, FAs 4 and FAs 9 were able to accumulate arsenic 39.16, 148 and 125 µg/L on the 4th, 3rd and 5th day of incubation, respectively. The isolates FAs 1, FAs 4 and FAs 9 were identified as Gram negative non endospore forming rods. In future, these novel isolates possess a great potential in biotechnology field, as bioremediation of arsenic contaminated soil and water can be done by employing arsenic accumulating bacteria which is an eco-friendly and cost effective method.

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Biodegradation of organophosphorus Pollutants by Soil Bacteria: Biochemical Aspects and Unsolved Problems

Biotekhnologiya ◽

10.21519/0234-2758-2020-36-4-126-135 ◽

2020 ◽

Vol 36 (4) ◽

pp. 126-135

Author(s):

T.V. Shushkova ◽

D.O. Epiktetov ◽

S.V. Tarlachkov ◽

I.T. Ermakova ◽

A.A. Leontievskii

Keyword(s):

Genome Sequencing ◽

Soil Bacteria ◽

Activity Regulation ◽

Bacterial Isolates ◽

Bacterial Strains ◽

Russian Science ◽

Degrading Bacteria ◽

Phosphorus Source ◽

Glyphosate Herbicide ◽

Enzymatic Pathways

The degradation of persistent organophosphorus pollutants have been studied in 6 soil bacterial isolates and in 3 bacterial strains adapted for utilization of glyphosate herbicide (GP) under laboratory conditions. Significant differences in the uptake of organophosphonates were found in taxonomically close strains possessing similar enzymatic pathways of catabolism of these compounds, which indicates the existence of unknown mechanisms of activity regulation of these enzymes. The effect of adaptation for GP utilization as a sole phosphorus source on assimilation rates of several other phosphonates was observed in studied bacteria. The newly found efficient stains provided up to 56% of GP decomposition after application to the soil in the laboratory. The unresolved problems of microbial GP metabolism and the trends for further research on the creation of reliable biologicals capable of decomposing organophosphonates in the environment are discussed. organophosphonates, glyphosate, biodegradation, bioremediation, C-P lyase, phosphonatase, degrading bacteria Investigation of phosphonatase and genome sequencing were supported by Russian Science Foundation Grant no. 18-074-00021.

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Isolation and Characterization of a Bacterial Strain Enterobacter cloacae (Accession No. KX438060.1) Capable of Degrading DDTs Under Aerobic Conditions and Its Use in Bioremediation of Contaminated Soil

Microbiology Insights ◽

10.1177/11786361211024289 ◽

2021 ◽

Vol 14 ◽

pp. 117863612110242

Author(s):

Sonal Suman ◽

Tanuja

Keyword(s):

Contaminated Soil ◽

Growth Parameters ◽

Chemical Properties ◽

Enterobacter Cloacae ◽

Maximum Growth ◽

Bacterial Degradation ◽

Biochemical Tests ◽

Isolation And Characterization ◽

16S Rna ◽

Degrading Bacteria

DDT is one of the most persistent pesticides among all the different types of organo-chlorine pesticides used. Among all the degradation methods, bacterial degradation of DDT is most effective. The present study was conducted to isolate different bacteria present in waste samples which have the ability to degrade DDT present in the soil in the minimum possible period of time and to observe the effect of different physical and chemical properties of the soil samples. Many pesticide degrading bacteria were isolated and identified through cultural, biochemical tests and further identified by 16S RNA sequencing method. The most potent strain DDT 1 growth in mineral salt medium supplemented with DDT as the only source of carbon (5-100 PPM) and was monitored at an optical density of 600 nm. The growth parameters at different physio-chemical conditions were further optimized. The result showed that Enterobacter cloacae had maximum growth in 15 days. FTIR analysis of the residual DDT after 15 days incubation showed that Enterobacter cloacae was able to degrade pesticide into its further metabolites of DDD, DDE, DDNU and other components can be used for biodegradation of DDT present in contaminated soil and water ecosystems.

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Isolation and Identification of Hydrocarbon-Degrading Bacteria that Tolerant to Saponin of Sapindus Rarak Plant

Jurnal Biodjati ◽

10.15575/biodjati.v4i1.4392 ◽

2019 ◽

Vol 4 (1) ◽

pp. 79-88

Author(s):

Evi Octaviany ◽

Suharjono Suharjono ◽

Irfan Mustafa

Keyword(s):

Crude Oil ◽

16S Rdna ◽

Bacterial Isolates ◽

High Concentration ◽

Isolation And Identification ◽

Rdna Sequences ◽

Degrading Bacteria ◽

16S Rdna Sequences ◽

Petroleum Contaminated Soil ◽

Cell Densities

A commercial saponin as biosurfactant can reduce the surface tension of water and increase of hydrocarbon degradation. However, this saponin can be toxic to some hydrocarbonoclastic bac-teria. This study aimed to obtain bacterial isolates that were tolerant and incapable to degrade saponin, and to identify them based on 16S rDNA sequence. Bacteria were isolated from petroleum contaminated soil in Wonocolo Village, Bojonegoro Regency, East Java, Indonesia. The soil samples were acclimated using Bushnell-Haas (BH) broth with 0.5% crude oil at room temperature for 3 weeks. The culture was spread onto BH agar incubated at 30°C for 7 days. The first screened, isolates were grown in nutrient broth with addition of sap-onin 0%, 8%, and 12% (v/v) then incubated at 30°C for three days. The bacterial cell density was measured using a spectrophotometer. Second screened, the isolates were grown on BH broth with addition of 0.5% saponin as a sole carbon source, and their cell densities were measured. The selected isolates were identified based on 16S rDNA sequences. Among 34 bacterial isolates, nine isolates were tol-erant to 12% saponin. Three bacterial isolates IHT1.3, IHT1.5, and IHT3.24 tolerant to high concentration of saponin and did not use this substance as growth nutrition. The IHT1.3, IHT1.5, and IHT3.24 isolates were identified as Ochrobactrum pseudogrignonense (99% similarity), Pseudomonas mendocina (99%), and Ochrobactrum pi-tuitosum; (97%), respectively. Those three selected isolates are good candidates as hydrocarbon-degrading bacteria to bioremediation of soil contaminated crude oil. However, the combined activity of bacteria and saponin to degrade hydrocarbon needs further study.

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Novel bacterial strains for the removal of microcystins from drinking water

Water Science & Technology ◽

10.2166/wst.2011.352 ◽

2011 ◽

Vol 63 (6) ◽

pp. 1137-1142 ◽

Cited By ~ 21

Author(s):

L. A. Lawton ◽

A. Welgamage ◽

P. M. Manage ◽

C. Edwards

Keyword(s):

Drinking Water ◽

Cost Effective ◽

Health Impact ◽

Effective Solution ◽

Bacterial Isolates ◽

Bacterial Strains ◽

Successful Isolation ◽

The World ◽

Water Treatments ◽

Significant Health

Microcystins (MC) and nodularin (NOD) are common contaminants of drinking water around the world and due to their significant health impact it is important to explore suitable approaches for their removal. Unfortunately, these toxins are not always removed by conventional water treatments. One of the most exciting areas that hold promise for a successful and cost effective solution is bioremediation of microcystins. Recent work resulted in successful isolation and characterisation of 10 novel bacterial strains (Rhodococcus sp., Arthrobacter spp. and Brevibacterium sp.) capable of metabolizing microcystin-LR (MC-LR) in a Biolog MT2 assay. The work presented here aims to further investigate and evaluate the metabolism and the degradation of multiple microcystins (MC-LR, MC-LF, MC-LY, MC-LW and MC-RR) and nodularin by the bacterial isolates. A total of five bacterial isolates representing the three genera were evaluated using Biolog MT2 assay with a range of MCs where they all demonstrated an overall metabolism on all MCs and NOD. Subsequently, the results were confirmed by observing the degradation of the range of toxins in a separate batch experiment.

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Isolation and Genetic Identification of Dibenzothiophene Degrading Bacteria from Contaminated Soil

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.610-613.292 ◽

2012 ◽

Vol 610-613 ◽

pp. 292-295 ◽

Cited By ~ 3

Author(s):

Lin Li ◽

Chao Cheng Zhao ◽

Qi You Liu ◽

Yun Bo Zhang

Keyword(s):

Phylogenetic Analysis ◽

Species Identification ◽

Contaminated Soil ◽

Bacterial Strain ◽

Degradation Efficiency ◽

Genetic Identification ◽

Microbial Consortia ◽

Bacterial Strains ◽

Bacterial Consortia ◽

Degrading Bacteria

The biodegradation abilities of 10 dibenzothiophene degrading microbial consortia isolated from contaminated soil were investigated. 5 highly efficient dibenzothiophene degrading bacterial strains were obtained from the consortium LKY10 by screening on LB-agar plates.The bacterial strain LKY10-5 reduced more than 90% of dibenzothiophene with 40 mg•L-1concentration, and had higher degradation efficiency than enriched bacterial consortia in 7 days of cultivation. According to species identification and phylogenetic analysis, strain LKY10-1 and LKY10-3 belonged to Actinobacteria and could be included in Rhodococcus and Cellulosimicrobium genus, LKY10-5 and LKY10-6 belonged to Proteobacteria and could be included in Pseudomonas and Devosia genus, and LKY10-13 could be included in Lysinibacillus genus and belonged to Firmicutes.

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Deciphering the Multi-Dimensional Abilities of Indigenous Bacteria Enterobacter Cloacae Isolated from Arsenic Contaminated Industrial Sites

10.21203/rs.3.rs-524502/v1 ◽

2021 ◽

Author(s):

Reeta Bhati ◽

Smitha Mony Sreedha ◽

Rajni Singh

Keyword(s):

Defense Mechanisms ◽

Toxic Metal ◽

Enterobacter Cloacae ◽

Maximum Growth ◽

Contaminated Site ◽

Bacterial Strains ◽

High Concentration ◽

Industrial Sites ◽

Zinc Cadmium ◽

Cadmium Selenium

Abstract Arsenic (As) is a quintessential toxic metalloid and it has been classified as Group 1 human carcinogen. The evolution of arsenic defense mechanisms due to the omnipresent nature of arsenic has resulted in its alteration to less toxic forms. The present study deals with the isolation of arsenic remediating microbial strains from soil samples and their integration into bioremediation strategy. From the metal contaminated site, 118 different bacterial strains were isolated from heavy metal contaminated site. Twenty-five strains were tolerant to arsenic and one bacterial strain Enterobacter cloacae (RSC3) demonstrated maximum growth at high concentration of arsenate (6000ppm). The cell growth kinetics of RSC3revealed the specific growth rate (µ) to be 0.55 h-1. The The bacteria hosts arsC gene in the genome involved in the reduction of arsenate to arsenite. AAS, SEM, TEM and EDX studies confirmed the arsenate transportation and efflux of arsenic by the bacteria. Furthermore, the strain showed multi-resistance to other heavy metals like zinc, cadmium, selenium and nickel and several antibiotics indicating its application for facilitating bioremediation of toxic metal contaminated sites.

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Screening and Identification of Glufosinate-Degrading Bacteria from Glufosinate-Treated Soils

Weed Science ◽

10.1614/ws-06-202.1 ◽

2007 ◽

Vol 55 (6) ◽

pp. 631-637 ◽

Cited By ~ 3

Author(s):

Chau-Ling Hsiao ◽

Chiu-Chung Young ◽

Ching-Yuh Wang

Keyword(s):

Denaturing Gradient Gel Electrophoresis ◽

Bacterial Strains ◽

High Concentration ◽

Degrading Bacteria ◽

Gradient Gel Electrophoresis ◽

Screening And Identification ◽

Polymerase Chain ◽

Competition Pressure ◽

Rdna Analysis

In order to select efficient and competitive glufosinate-degrading bacteria, two soils which had been treated with glufosinate annually for more than 5 yr were screened. Three strains tolerant to this herbicide were identified by 16S rDNA analysis asBurkholderia sacchari,Serratia marcescens, andPseudomonas psychrotolerans. In addition, a moderately tolerant strain,P. citronellolis, was isolated from a soil which had received glufosinate treatment for only 6 mo. In culture medium containing high concentration of glufosinate, the former three strains showed significant ability to degrade this glutamine synthetase inhibitor, suggesting that glufosinate-degrading bacteria would be readily found in soils after a long-term induction or selection. A subsequent biodegradation experiment showed that 30 and 50% of glufosinate was degraded 7 and 21 d after treatment (DAT), respectively, in sterilized soils inoculated with the above-mentioned three tolerant strains. While more than 30% of the glufosinate in nonsterilized soils was degraded 7 DAT by the indigenous edaphic microbes, inoculation with the three selected strains enhanced glufosinate degradation to nearly 50%. A study on the competition from edaphic microorganisms in soils by polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) analysis revealed that within 21 d after inoculation (DAI), the propagation ofB. sacchariandP. psychrotoleranswas not affected, whereas that of the less tolerantP. citronelloliswas inhibited. This observation suggests that a long-term herbicide exposure is a promotive factor in generating bacterial strains having high degradation efficiency and showing vigorous propagation under the competition pressure arising from indigenous microbes.

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Isolation of Arsenic Oxidizing-reducing Bacteria and Reclamation of As (III) in in vitro Condition

Bangladesh Rice Journal ◽

10.3329/brj.v19i2.28170 ◽

2016 ◽

Vol 19 (2) ◽

pp. 99-101

Author(s):

UA Naher ◽

F Rahman ◽

SMM Islam ◽

MIU Sarkar ◽

JC Biswas

Keyword(s):

Contaminated Soil ◽

Water Samples ◽

Broth Culture ◽

Plate Count ◽

Bacterial Strains ◽

Oxidation Activity ◽

Plate Count Method ◽

Reducing Bacteria ◽

Soil And Water

CORRECTION: Due to a number of formatting and layout issues, the PDF of this paper was replaced on 10th October 2016. The page numbers of this article have changed from 94-96 to 99-101.The study aimed to isolate arsenic (As) oxidizing-reducing bacteria from As contaminated soil and water and to determine their ability to remove As from broth culture. Soil and water samples were collected from As contaminated area of BRRI farm, Bhanga, Faridpur. Arsenic oxidizing and reducing bacteria were isolated from the As contaminated soil (13 mg kg-1) and water (410 ?g/L) using spread plate count method in minimal salt (MS) medium after seven days of incubation. The oxidation activity of the bacteria as well as reclamation of As [III] was determined from NaAsO2 supplemented broth using atomic absorption spectrophotometer (AAS). The As-oxidizing bacteria population was present only in one soil sample, while in all water samples both oxidizing and reducing bacteria were present. A total of 36 As oxidizing-reducing bacteria were isolated. As-oxidizing bacteria removed 71-99% of applied As [III] in broth culture. Two out of 10 As-oxidizing bacterial strains appeared more efficient than others to remove As [III] under broth culture conditions.Bangladesh Rice j. 2015, 19(2): 99-100

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Diversity and PAH growth abilities of bacterial strains isolated from a contaminated soil in Slovakia

Biologia ◽

10.2478/s11756-013-0193-3 ◽

2013 ◽

Vol 68 (4) ◽

Cited By ~ 13

Author(s):

Andrea Puškárová ◽

Mária Bučková ◽

Katarína Chovanová ◽

Jana Harichová ◽

Edita Karelová ◽

...

Keyword(s):

Contaminated Soil ◽

Bacterial Isolates ◽

Bacterial Strains ◽

Hydrocarbonoclastic Bacteria ◽

Promising Strategy ◽

Rrna Sequencing ◽

Polycyclic Aromatic ◽

Polluted Sites ◽

Arthrobacter Oxydans ◽

Environmental Burdens

AbstractDifferent abandoned industrial areas contaminated by polycyclic aromatic hydrocarbons (PAHs) are present in Slovakia. These environmental burdens are very dangerous to the health of human and environment. The bioremediation, based on the use of hydrocarbons degrading microorganisms, is a promising strategy to sanitize these polluted sites. The aim of this investigation was to assess the bacterial diversity of a PAHs-contaminated soil and to select the potential hydrocarbonoclastic bacteria which can be used for different bioremediation approaches. The bacterial strains were isolated on minimal medium agar supplemented with a mixture of PAHs. Seventy-three isolated strains were grouped by ribosomal interspacer analysis in 15 different clusters and representatives of each cluster were identified by 16S rRNA sequencing. The PAHs degradation abilities of all bacterial isolates were estimated by the 2,6-dichlorophenol indophenol assay and by their growth on minimal broth amended with a mixture of PAHs. Different kinds of strains, members of the genus Pseudomonas, Enterobacter, Bacillus, Arthrobacter, Acinetobacter and Sphingomonas, were isolated from the contaminated soil. Four isolates (Pseudomonas putida, Arthrobacter oxydans, Sphingomonas sp. and S. paucimobilis) showed promising PAHs-degrading abilities and therefore their possible employing in bioremediation strategies.

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Bioremediation of Petroleum Polluted Soils using Consortium Bacteria

Iraqi Journal of Science ◽

10.24996/ijs.2020.61.5.3 ◽

2020 ◽

pp. 961-969

Author(s):

Dina Hasan Nafal ◽

Hind Suhail Abdulhay

Keyword(s):

Bacillus Amyloliquefaciens ◽

Oxygen Demand ◽

Cost Effective ◽

Bacterial Consortium ◽

Gas Chromatography Mass Spectrometry ◽

Bacterial Strains ◽

Degrading Bacteria ◽

Oil Concentration ◽

Kocuria Rosea ◽

Physical And Chemical

This study was carried out to isolate opportunistic hydrocarbons oil-degrading bacteria and develop a consortium or a mixture of bacteria with high biodegradation capabilities which can be used in biological treatment units of the contaminated water before release. The biological processes in general are environmentally friendly and cost effective, as they are easy to design and apply; as such they are more appropriate to the public. The location of the study was in Al-Dora refinery sludge holes area. The samples were collected for three seasons (winter, spring and summer) each consisted of three months. The sludge samples were analyzed for various physical and chemical parameters. Temperature values of the sludge were at maximum in summer season, reaching 32˚C, whereas they were at minimum in winter (24 ˚C). The values of sludge pH were at maximum in summer (9.70) and minimum in winter (9.20). Turbidity levels were 382 NTU in spring and 353 NUT in winter. Biological oxygen demand (BOD5) was at maximum in summer (760) and (690 mg/l) in winter. The maximum dissolved oxygen (DO) value of 5.20 mg/l was recorded in winter, while the minimum was 3.80 mg/l recorded in summer. The maximum electrical conductivity (EC) was 17130 μs/cm recorded in summer, while the minimum was 16150 μs/cm recorded in winter. The maximum total dissolved solids (TDS) values were 10335 mg/l recorded in summer, while the minimum (10015 mg/l) was recorded in winter. The maximum total petroleum hydrocarbon (TPH) value (431 mg/l) was recorded in summer, while the minimum (367 mg/l) was recorded in spring. Finally, the maximum salinity value (9.90%) was recorded in spring, while the minimum (9.30%) was recorded in winter. Also, hydrocarbon compounds in sludge samples were measured using Gas Chromatography - Mass Spectrometry (GC-MS), and the result showed that they were composed of 31 hydrocarbon compounds.In the present work, nineteen sludge degrading bacterial strains were isolated from the soil near Al-Dora refinery hole by primary and secondary screenings using a modified mineral salt medium supplemented with 1% (v/v) sludge as a carbon source. The most efficient two sludge degraded isolates identified by VITIK 2 compact were Kocuria rosea and Bacillus amyloliquefaciens. The tow isolates and there mixture showed best growth at 30°C for 12 days, as shown by the measurement of the optical density of the liquid culture and the final oil concentration by spectrophotometer. The bacterial isolates in liquid media with 2% (v/v) sludge showed best growth and the maximum biodegradation percentage after 12-day incubation period, as determined by gas chromatographic (GC). The degradation values were 68.9, 93.8 and 95.5% for Bacillus amyloliquefaciens, Kocuria rosea and the mixture of the tow isolates, respectively. In optimum conditions of pH 7, 40°C, 12 days incubation, the mixed bacterial consortium showed maximum sludge degradation.

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