Search results for "Biodegradation"
showing 10 items of 317 documents
Biodegradation of Crude Oil by Individual Strains and a Mixed Bacterial Consortium in Simulation of Marine Environment
2013
Petroleum hydrocarbons are the most widespread contaminants in the marine environment. The fate of petroleum in sea water is largely controlled by mechanical, physical and chemical factors which influencing the natural transformation of petroleum (oil weathering) and oil bio-degradation. On the basis of these considerations, bioremediation techniques have been developed and improved for cleaning up oil-polluted marine environment as alternative to chemical and physical techniques. To elucidate the cooperative action of mixed microbial populations in the biodegradation of crude oil, we constructed artificial consortia composed of two to three bacteria (Alcanivorax borkumensis strain SK2, Rho…
Intrinsic bioremediation potential of a chronically polluted marine coastal area.
2015
A microbiological survey of the Priolo Bay (eastern coast of Sicily, Ionian Sea), a chronically polluted marine coastal area, was carried out in order to discern its intrinsic bioremediation potential. Microbiological analysis, 16S rDNA-based DGGE fingerprinting and PLFAs analysis were performed on seawater and sediment samples from six stations on two transects. Higher diversity and variability among stations was detected by DGGE in sediment than in water samples although seawater revealed higher diversity of culturable hydrocarbon-degrading bacteria. The most polluted sediment hosted higher total bacterial diversity and higher abundance and diversity of culturable HC degraders. Alkane- an…
Hydrocarbon degrading bacteria vs microbial consortia in the degradation of Policyclic Aromatic Hydrocarbons
2014
The Harbor of Priolo Gargallo is a chronically polluted area in Sicily (Italy). Bioremediation is an alternative friendly strategy to reduce environmental risks that relies on microorganisms that play a key role in the biodegradation of hydrocarbon contaminants. In this study, sediment samples were collected in 6 stations inside the area indicated. Analysis of total hydrocarbons, microbial abundance (DAPI, CFU and MPN), and total bacterial diversity (DGGE) were carried out. Enrichment cultures and isolation of hydrocarbon-degrading bacteria were carried out in the mineral medium ONR7a with a mix of Polycyclic Aromatic Hydrocarbons [PAHs-Mix; Methylnaphtalene, Byphenile, Phenantrene, Dibenzo…
The organic carbon derived from sewage sludge as a key parameter determining the fate of trace metals.
2007
8 pages; International audience; In a sandy agricultural soil of south-west of France, continuously cultivated with maize and amended with sewage-sludge over 20 years, the behavior of three trace metals (Cu, Pb, and Zn) was studied during the sludge applications (1974-1993) and after its cessation (1993-1998). Using the delta13C analysis, the dynamics of different sources of organic matter were followed in order to elucidate the influence of the sludge-derived organic matter on the fate of trace metals in the soil and its particle size fractions. This study revealed that sludge-derived organic matter contributed to the formation of macroaggregates through the binding of preexisting microagg…
Plant diversity enhances the natural attenuation of polycyclic aromatic compounds (PAHs and oxygenated PAHs) in grassland soils
2019
Increasing plant species richness stimulates microbial activity in soil, which might favor biodegradation of polycyclic aromatic compounds (PACs). To explore the relationship between plant community composition and PACs in grassland soils (Fluvisols exposed to an urban atmosphere), we determined the concentrations of 29 polycyclic aromatic hydrocarbons (PAHs) and 15 oxygenated PAHs (OPAHs) in topsoils of 80 plots of a grassland biodiversity experiment. The plots included different levels of plant species richness (1, 2, 4, 8, 16, 60 species) and 1–4 plant functional groups (grasses, small herbs, tall herbs, and legumes) in a randomized block design. The concentrations (ng g−1) of ∑29PAHs an…
Dependence of accelerated degradation of atrazine on soil pH in French and Canadian soils
2000
Abstract A series of agricultural soils varying in their atrazine treatment history were sampled from 12 sites in France and two sites in Canada. The soils varied widely with respect to soil chemical, physical and microbiological (total microbial biomass, kinetics of C and N mineralization) properties. Soils treated with as few as two successive atrazine field applications mineralized [U- ring - 14 C]atrazine significantly more rapidly in 35 d laboratory incubations than did soils which had never received atrazine. Longer treatment history tended to favour more rapid mineralization in the so-called “adapted” soils. Up to 80% of the initially applied 14 C-atrazine was mineralized at the end …
Influence of substrate and temperature on the biodegradation of polyester-based materials: Polylactide and poly(3-hydroxybutyrate-co-3-hydroxyhexanoa…
2020
[EN] The extended use of polymers from renewable resources such as aliphatic polyesters or polyhydroxyalkanoates boosted the necessity to understand their behaviour in an end-of-life scenario. Although they can be degraded in reasonable shorter times than traditional polymers, understanding the degradation mechanisms under dissimilar conditions will contribute to further developments in this field. This work aimed to study the effect of temperature and substrate in the degradation of polylactide (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) in a simulated laboratory scale to ascertain their contribution, separately or in combination. For this purpose, nine parallel degradat…
Carbon Nanomaterial Doped Ionic Liquid Gels for the Removal of Pharmaceutically Active Compounds from Water.
2019
Due to large drug consumption, pharmaceutically active compounds (PhACs) can be found as water contaminants. The removal of PhACs is a significant issue, as they can easily overtake traditional purification methods. Because of their surface properties, carbon nanomaterials are among the most efficient materials able to adsorb PhACs. However, their limitation is their recovery after use and their possible leakage into the aquatic system. Consequently, new hybrid supramolecular ionic liquid gels (HILGs) have been designed for the adsorption of some antibiotic drugs (ciprofloxacin and nalidixic acid) from water. The chemical&ndash
Evaluation of carbamazepine uptake and metabolization by Typha spp., a plant with potential use in phytotreatment
2011
Abstract Phytoremediation technologies such as constructed wetlands have shown higher efficiencies in removal of pharmaceuticals from wastewaters than conventional wastewater treatment processes, and plants seem to have an important role in the removal of some of those compounds. In this context, a study was conducted to assess tolerance, uptake, and metabolism of the epilepsy drug, carbamazepine, by the macrophyte Typha spp. This evaluation was conducted in hydroponic solutions with 0.5–2.0 mg/L of this pharmaceutical for a maximum period of 21 days. The removal of carbamazepine from nutrient solutions by the plants reached values of 82% of the initial contents. Furthermore, a metabolite (…
Differential proteomics highlights metabolic changes associated with n-hexadecane utilization in a Streptomyces coelicolor strain expressing Gordonia…
2011
Introduction: Alkanes are biodegraded to generate the corresponding primary alcohol trough alkane hydroxylases (AHs) consisting on an integral membrane alkane monooxygenase (AlkB) and two soluble proteins, rubredoxin and rubredoxin reductase. Recently, an alkB gene was reported to be involved in degradation of long chain n-alkanes in the actinobacterium Gordonia sp. SoCg. This gene was expressed in Streptomyces coelicolor M145 which is unable to degrade n-alkanes. Results: The engineered strain, M145-AH, can biotransform n-hexadecane into the corresponding 1-hexadecanol and it is able to grow on n-hexadecane as sole carbon source. Changes in global protein expression associated with n-hexad…