Introduction

According to the WHO data polychlorinated biphenyls (PCBs) are among twelve most dangerous and hardly decomposed environmental pollutants. Until recently they had been broadly used for the electro-technical and chemical industries because of extreme persistence in the environment. They cannot be decomposed photolytically, chemically, and biologically. However, polychlorbiphenyls are highly toxic, are accumulated in human organism and have carcinogenic effect. Processes of soil self-cleanup are...

Pseudomonas Putida F1 Continues To Amaze

Bioavailability of organic pollutants refers to the ability of microorganisms to reach and desorb pollutant molecules from the soil matrix in a bioremediation setting where biodegradative microorganisms such as those represented by numerous Pseudomonas spp. are used to detoxify or attenuate the culprit pollutants (Alexander, 1994). Approximately 20-30 of the bacteria listed in the Biodegradative Strain Database of the Michigan State University (http bsd.cme.msu.edu) and the Biocatalysis...

Results And Discussion

Biological remediation of chromate-containing wastewater is based on bacteria consumption of Cr (VI) as a terminal electron acceptor during the breathing. The capability of Cr (VI) reduction is not uncommon among Cr (Vl)-resistant microorganisms. The ability of denitrifying and fermenting bacteria to reduce chromium (VI) in anaerobic and aerobic condition is shown by many researchers 3-5,8 . Studding of oxidation-reducation potential (ORP) of nutrient medium during microbial chromate reduction...

Systems

Surfactants are amphipathic molecules that form aggregates known as micelles at concentrations above a threshold, referred to as the critical micelle concentration (CMC). In aqueous solutions, surfactant micelles solubilize HOCs and increase the apparent solubility of these sparingly soluble compounds. The potential of surfactant in enhancing bioremediation is not well understood. Some studies reported inhibition of HOC biodegradation in the presence of surfactants, whereas others observed...

References

1 D' Adamo PCD, Rozich AF, Gaudy AF. Analysis of growth data with inhibitory compounds. Biotech & Bioengg 1984 26 397-02. 2 Hinteregger C, Leitner R, Loidl M, Ferschl A, Streichsbier F. Degradation of phenol and phenolic compounds by Pseudomonas putida EKII. Appl Microbiol Biotechnol 1992 37 252-59. 3 Leonard D, Lindley N. Growth of Ralstonia eutropha on inhibitory concentrations of phenol diminished growth can be attributed to hydrophobic perturbation of phenol hydroxylase activity. Enz...

Atrazine Degradation By Pseudomonas sp Adp Is Nitrogen Regulated

Different Nitrogen Sources

A major issue in developing strains suitable for bioremediation is the ability of the chosen organism to display an efficient degradative phenotype under field conditions. Since most atrazine-degrading strains use it as a nitrogen source and agricultural soils are often rich in nitrogen due to routine fertilization, the effect of nitrogen amendments on atrazine degradation has been tested both in culture and in soil. Addition of inorganic and organic nitrogen has repeatedly been shown to retard...

Bioremediation of soils contaminated by PCB

Trails of developed technology for bioremediation of soils, contaminated by PCB were conducted on the territory of Serpukhov within the framework of ISTC Project 2093 during summer of 2001. Serpukhov administration rendered active assistance in the work conducting. 8 most contaminated Serpukhov sites with total area - 2 hectares were selected for trials of the bioremediation technology. 4 of them were on the territory of SPA Condensator , and the other 4 were on the adjoining living territory...

Bioavailability

In soil, a xenobiotic may be considered to be in dynamic equilibrium between three potential phases (i) freely dissolved in the soil solution (ii) adsorbed to water-soluble humic material or (iii) adsorbed to the soil organo-mineral solid colloidal phase. Of that proportion of the xenobiotic that is adsorbed, further distinction can be made between that which is surface-adsorbed and that which is sequestered (i.e. absorbed within three-dimensional structures) (Fig. 2). A bioavailable compound...

The Role Of Plants And Bacteria In Phytoremediation Kinetic Aspects

Ucisik, Paola DelChicca Romano and Morten Larsen Environment & Resources DTU Technical University of Denmark DK-2800 Kongens Lyngby, Denmark stt er.dtu.dk Abstract Phytoremediation is the common name for cleaning techniques for polluted soils, sediments, and wastewaters using plants. It has been shown repeatedly that several types of pollutants, e.g., petroleum products and solvents, are degraded faster in the presence of plants. A couple of processes are known to...

Complex Regulation Of The atzDef Operon

Nitrogen control of atrazine degradation could have several possible targets. The atzA, atzB and atzC genes are generally regarded as constitutively expressed, based on the lack of evident regulatory regions and Northern blots of atzA and atzB (Martinez et al., 2001). However, atzD, atzE and atzF are grouped in an operon and are transcribed divergently from atzR, encoding a LysR-type regulator. Experiments with atzD-lacZ fusions showed that atzDEF expression is low in ammonium-grown cells,...

Conclusions

The enzymes phenol hydroxylase and catechol 1,2-dioxygenase of Trichosporon cutaneum studied exhibited certain similarities and differences compared to similar enzymes isolated from other microorganisms. It should be pointed out, that the levels of phenol hydroxylase activities established in the present research are higher than the results cited in the literature 29,30,31 . On the basis of our previous and recent analyses, the investigated strain and some of its mutants were considered to have...

The Rhizosphere And Rhizodeposition

The existence of a distinctive microbial plant root environment, the rhizosphere, has been recognised for over a century Hiltner, 1904 . This spatially and temporally dynamic environment, when viewed in cross-section, may be categorized further to recognise sub rhizosphere zones the H.J. Heipieper ed. , Bioremediation of Soils Contaminated with Aromatic Compounds, 5-3 0. 2007 Springer. ectorhizosphere soil influenced by the root , endorhizosphere intercellular space between the root tissues and...

List Of Participants

Institute of Molecular and Cell Biology University of Tartu Riia 23, 51010 Tartu Estonia E-mail tiina.alamae ut.ee Tel 372 7375013 Fax 372 7420286 Institute of Microbiology, Bulg.Acad.Sci. 1113 Sofia, Acad.G.Bontchev, bl.26 Bulgaria E-mail zlatkama microbio.bas.bg Tel 359029793114 Fax 359028700109 Institute of Molecular and Cell Biology University of Tartu Riia 23, 51010 Tartu Estonia E-mail koit candor.ee Tel 372 7375015 Fax 372 7420286 Tallinn Technical University Raudtee 10-1, 11614 Tallinn...