A Comparison of In-vitro PAH Bioaccessibility in Historically Contaminated Soils: Implications for Risk Management

The indoleacetic acid produced by symbiotic bacteria is an important phytohormone signaling microbe-plant interaction, being therefore essential for rhizoremediation. In this study, the effect of different concentrations of copper ions on the bacterial growth and indoleacetic acid production was investigated in two strains of Mesorhizobium loti in in vitro conditions, aiming to determine critical concentrations of this heavy metal for rhizoremediation of contaminated soils using this bacterium. The experiment consisted on a control culture without copper and three treatments supplemented with 10 mg.L-1, 20 mg.L-1 or 50 mg.L-1 of CuSO4. For both strains, the growth stopped after 48h and no significant difference was observed across treatments. The production of indoleacetic acid by the control treatment without copper was significantly higher in comparison to the copper- containing treatments. Mesorhizobium loti SEMIA806 and SEMIA816 are resistant to up to 50 mg.L-1 of CuSO4 in the culture medium, presenting effective growth. The synthesis of indoleacetic acid was strongly reduced but not excluded by ions copper in the medium. So, it is expected that environmental copper found in the soil up to the concentration of 50 mg.L-1 will not preclude the symbiotic interaction between M. loti and leguminous host plant in rhizoremediation enterprises.

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Isolation and characterization of arsenic resistant soil bacteria and their effects on germination of rice under arsenic contamination

Research in Agriculture Livestock and Fisheries ◽

10.3329/ralf.v2i2.25003 ◽

2015 ◽

Vol 2 (2) ◽

pp. 229-237

Author(s):

Istiaq Ahmed ◽

Md Tofazzal Islam ◽

Md Akhter Hossain Chowdhury ◽

Md Kamruzzaman

Keyword(s):

Contaminated Soils ◽

Sodium Arsenite ◽

Agar Plate ◽

Rice Seedling ◽

Resistant Bacteria ◽

Gram Staining ◽

Isolation And Characterization ◽

Resistant Strains

This study was carried out to isolate, screen and characterize arsenic (As) resistant bacteria from As contaminated soils of Dumrakandi and Matlab under Faridpur and Chandpur districts and to evaluate their efficiency in reducing As toxicity against rice seedlings during germination. Thirteen strains were isolated from the soils which showed resistance to different levels of sodium arsenite (viz. 5, 10, 20 and 40 mM) in both agar plate and broth assay using BSMY I media. Among the isolates, BTL0011, BTL0012, BTL0015 and BTL0022 showed highest resistance to 40 mM sodium arsenite. Gram staining and KOH solubility test revealed that five strains were gram positive and rest eight was gram negative. They grew well in the liquid media at pH 5.5 to 8.5. In-vitro rice seedling bioassay with two superior isolates (BTL0011 and BTL0022) revealed that As resistant strains significantly enhanced seed germination of BRRI dhan29 and BRRI dhan47 at 60 ppm As. This study was laid out in CRD with three replications. The performance of BTL 0022 was superior to BTL0011. The overall results suggest that BTL0011 and BTL0022 can be used for bioremediation of As contaminated soils and to increase the germination and seedling growth of rice in As contaminated soils.Res. Agric., Livest. Fish.2(2): 229-237, August 2015

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In vitro and in vivo approaches for the measurement of oral bioavailability of lead (Pb) in contaminated soils: A review

Environmental Pollution ◽

10.1016/j.envpol.2011.04.043 ◽

2011 ◽

Vol 159 (10) ◽

pp. 2320-2327 ◽

Cited By ~ 68

Author(s):

Munir Hussain Zia ◽

Eton E. Codling ◽

Kirk G. Scheckel ◽

Rufus L. Chaney

Keyword(s):

Contaminated Soils ◽

Oral Bioavailability

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An In Vitro Control Study To Test The Fungus Trichoderma Harzianum Strain T 22 For Contaminated Soils Bioremediation

ISEE Conference Abstracts ◽

10.1289/isee.2015.2015-1038 ◽

2015 ◽

Vol 2015 (1) ◽

pp. 1038

Author(s):

Antonio Cristaldi ◽

Gea Oliveri Conti ◽

Alfina Grasso ◽

Giovanni Arena ◽

Chiara Copat ◽

...

Keyword(s):

Trichoderma Harzianum ◽

Contaminated Soils ◽

Control Study

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Determination of Cadmium Relative Bioavailability in Contaminated Soils and Its Prediction Using in Vitro Methodologies

Environmental Science & Technology ◽

10.1021/es1006516 ◽

2010 ◽

Vol 44 (13) ◽

pp. 5240-5247 ◽

Cited By ~ 55

Author(s):

Albert L. Juhasz ◽

John Weber ◽

Ravi Naidu ◽

Dorota Gancarz ◽

Allan Rofe ◽

...

Keyword(s):

Contaminated Soils ◽

Relative Bioavailability

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Molecular identification of three isolates of Trichoderma harzianum isolated from agricultural soils in Argentina, and their abilities to detoxify in vitro metsulfuron methyl

Botany ◽

10.1139/cjb-2015-0085 ◽

2015 ◽

Vol 93 (11) ◽

pp. 793-800 ◽

Cited By ~ 2

Author(s):

María Belén Vázquez ◽

Viviana Barrera ◽

Virginia Bianchinotti

Keyword(s):

Trichoderma Harzianum ◽

Contaminated Soils ◽

Lens Culinaris ◽

Agricultural Soils ◽

Degradation Products ◽

Cereal Crops ◽

Sulfonylurea Herbicide ◽

Metsulfuron Methyl ◽

Germinated Seeds

Metsulfuron methyl (MM) is a sulfonylurea herbicide used worldwide for the control of weeds in cereal crops. In a previous study, three Trichoderma strains (T5, T6, and T7) capable of using MM as a sole carbon and energy source were isolated. In this study, the three strains were identified as Trichoderma harzianum using genetic markers, and the transformation of MM by the T. harzianum strains was quantified using spectrophotometry. Solutions of different phytotoxic doses of MM were incubated with plugs of mycelia of the Trichoderma strains and the resulting mixtures were used to assess MM detoxification. The toxicity of the degradation products was tested with a bioassay using pre-germinated seeds of Lens culinaris Medik. and mycelia. Strain T7 was more efficient in transforming MM at higher concentrations than the T5 and T6 strains. In the bioassay, T5 showed the best performance at higher MM doses. We conclude that both T5 and T7 strains are promising for further studies regarding treatment or amelioration of MM contaminated soils.

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