Bioremediation Potential of Native Hydrocarbons Degrading Bacteria in Crude Oil Polluted Soil

Bioremediation of crude oil contaminated soil is an effective process to clean petroleum pollutants from the environment. Crude oil bioremediation of soils is limited by the bacteria activity in degrading the spills hydrocarbons. Native crude oil degrading bacteria were isolated from different crude oil polluted soils. The isolated bacteria belong to the genera Pseudomonas, Mycobacterium, Arthrobacter and Bacillus. A natural biodegradable product and bacterial inoculum were used for total petroleum hydrocarbon (TPH) removal from an artificial polluted soil. For soil polluted with 5% crude oil, the bacterial top, including those placed in the soil by inoculation was 30 days after impact, respectively 7 days after inoculum application, while in soil polluted with 10% crude oil,  multiplication top of bacteria was observed in the determination made at 45 days after impact and 21 days after inoculum application, showing once again how necessary is for microorganisms habituation and adaptation to environment being a function of pollutant concentration. The microorganisms inoculated showed a slight adaptability in soil polluted with 5% crude oil, but complete inhibition in the first 30 days of experiment at 10% crude oil

THE DIVERSITY OF HETEROTROPHIC BACTERIAL MICROFLORA IN SOIL POLLUTED WITH CRUDE OIL AND DIFFERENT TREATMENTS

Petroleum hydrocarbon pollution is one of the main environmental problems, not only bythe important amounts released but also because of their toxicity. It is known that the mainmicroorganisms consuming petroleum hydrocarbons are bacteria. The present researchwork reports the diversity of microrganis from crude oil polluted soil been treated with anatural biodegradable product and bacterial inoculum. The bacterial inoculum was used toenrich indigenous microbes to enhance biodegradation rate. In soil excessively polluted with crude oil, bacterial population size in conditioned variant with Ecosol maximum dose (1%) presented values comparable to those of inoculated variants, demonstrating the protective and stimulation effect of soil bacteria, including those involved in the degradation of petroleum hydrocarbons exercised by organic compound applied Ecosol

THE INFLUENCE OF DIFFERENT TREATMENTS OF SOIL POLLUTED WITH CRUDE OIL ON PLANT BIOMASS

The aim of this research was to improve the bioremediation technology for soils that are polluted with crude oil through biostimulation, bioaugmentation and phytoremediation. The soil artificial polluted with crude oil have been treated with a natural biodegradable product and bacterial inoculum. The plant used in the greenhouse experiment is maize. In this paper is presented the influence of different treatments on plant biomass. It will be shown the influence of crude oil on plant growth (plant number/pot, plant length, leaves number and plant biomass) in a soil treated with a natural biodegradable product and inoculated with bacterial inoculum. According with the results obtained, this method could be used in field for rehabilitation and reuse in agriculture of polluted soils with crude oil

A review on different bioremediation technologies for soil polluted with petroleum hydrocarbons

Crude oil and its derivates now has become a threat to environment due to extraction and transportation. Accidental oil spills occur regularly at many locations throughout the world. Contamination / pollution of soil with petroleum hydrocarbons has become a serious problem. Various physical, chemical and biological remediation strategies have been used to restore polluted soils. For bioremediation technology application, it is necessary to know the optimizing ways of the biodegradation process. Even though cost the of soil decontamination is roughly similar in many ways, more and more of pollution research is directed to biotechnological methods based on the ability of microorganisms to degrade certain pollutants under both natural conditions and through anthropogenic intervention meant to shorten the time of ecological reconstruction of polluted sites. Bioremediation can be divided into two basic types: natural attenuation, which can be applied when the natural conditions are suitable for the performance of bioremediation without human intervention, and engineered bioremediation, which is used when is necessary to add substances that stimulate microorganisms. Soil bioremediation technologies could be in situ or ex situ. As bioremediation technologies in situ cand be applied: biostimulation, bioaugmentation, bioventing, stimulation with surfactans, phytoremediation, use of agricultural land, natural attenuation, biobubbling, cometabolism. Ex situ bioremediation technologies could be achieved by bioreactors, hovering the land, biopile, composting

A REVIEW OF BIOLOGICAL METHODS TO REMEDIATE CRUDE OIL POLLUTED SOIL

Environmental pollution by crude oil can occur naturally through seepage or from anthropogenic sources via spillage, accidents or improper disposal of crude oil and related products. The main characteristic of pollution from refinery and petrochemical plants consists in that the pollution source is active, most often for a short period of time, but has an important intensity, polluting agent consisting generally of petroleum fractions. Also, in most cases of accidental spills of petroleum products, surface soil affected is much smaller than the first surface polluted aquifer pollution front met. Recent research has shown that biological methods to remediate crude oil polluted soil are a superior effective and much cheaper method compared with physicochemical methods. Biological methods are based on the activity of microorganisms to use crude oil as a source of carbon and energy. These methods are considered to be the most effective because it does not have irreversible effects on soil characteristics. Microorganisms such as bacteria, cyanobacteria, yeasts and fungi break down these dangerous chemicals into less toxic or non-toxic compounds

THE EFFECT OF RADIONUCLIDES AND HEAVY METALS ON THE ULTRASTRUCTURAL FEATURES OF LEAVES IN HELIANTHUS ANNUUS

The ultrastructural features of the leaf in mature plants of Helianthus annuus (during flowering), cultivated in three different areas: in normal culture (Floresti village, Cluj district) and in cultures on sites polluted with heavy metals and radionuclides: (a) near the power station Turceni and (b) on sterile waste dump in the Pedological Research Station of Rovinari (Gorj district), were analyzed. The soil analysis in the three sites showed a higher content in radionuclides and heavy metals, especially on the soil from Turceni, as compared to Control. The ultrastructural analysis pointed out the effect of the presence of high amounts of radionuclides and heavy metals, as well as the plant reaction: the parietal disposition of the heterochromatin in the nucleus in the shape of bodyguard, synthesis and accumulation of some substances (probably with antioxidant or chelating role) in vacuoles, which interacted with exogenous particles, a/

Zinc Regime in the Sewage Sludge-Soil-Plant System of a City Waste Water Treatment Pond

The sewage sludge from wastewater treatment plant of Iasi, a city with 300,000 inhabitants, for domestic and industrial origin, was stored in a mud pond arranged on an area of 18,920 m2. Chemical analyzes of the sludge showed that, of all the chemical elements determined, only Zn is found at pollutant level (5739 mg∙kg-1), i.e. almost 30 times more than the maximum allowable limit for Zn in soil and 45 times more than the Zn content of the soil on which the mud pond has been set. Over time, the content of Zn in the mud pond, but also from soil to which it has been placed, has become upper the normal content of the surrounding soil up to a depth of 260 cm. On the other hand, the vegetation installed on sewage sludge in the process of mineralization, composed predominantly of Phragmites, Rumex, Chenopodium, and Aster species had accumulated in roots, stems and leaves Zn quantities equivalent to 1463 mg Kg-1, 3988 mg Kg-1, 1463 mg Kg-1, respectively, 1120 mg∙Kg-1. The plants in question represents the natural means of phytoremediation, and sewage sludge as such may constitute a fertilizer material for soils in the area, on which Zn deficiency in maize has been recorded. In addition, the ash resulted from the incineration of plants loaded with zinc may constitute, in its turn, a good material for fertilizing of the soils that are deficient in zinc

Zinc Regime in the Sewage Sludge-Soil-Plant System of a City Waste Water Treatment Pond

The sewage sludge from wastewater treatment plant of Iasi, a city with 300,000 inhabitants, for domestic and industrial origin, was stored in a mud pond arranged on an area of 18,920 m2. Chemical analyzes of the sludge showed that, of all the chemical elements determined, only Zn is found at pollutant level (5739 mg∙kg-1), i.e. almost 30 times more than the maximum allowable limit for Zn in soil and 45 times more than the Zn content of the soil on which the mud pond has been set. Over time, the content of Zn in the mud pond, but also from soil to which it has been placed, has become upper the normal content of the surrounding soil up to a depth of 260 cm. On the other hand, the vegetation installed on sewage sludge in the process of mineralization, composed predominantly of Phragmites, Rumex, Chenopodium, and Aster species had accumulated in roots, stems and leaves Zn quantities equivalent to 1463 mg Kg-1, 3988 mg Kg-1, 1463 mg Kg-1, respectively, 1120 mg∙Kg-1. The plants in question represents the natural means of phytoremediation, and sewage sludge as such may constitute a fertilizer material for soils in the area, on which Zn deficiency in maize has been recorded. In addition, the ash resulted from the incineration of plants loaded with zinc may constitute, in its turn, a good material for fertilizing of the soils that are deficient in zinc