Biomaterial Database

Effect of humic fractions and clay on biodegradation of phenanthrene by a Pseudomonas fluorescens strain isolated from soil. 1998

J J Ortega-Calvo, and C Saiz-Jimenez

Instituto de Recursos Naturales y Agrobiologia, C.S.I.C., Apartado 1052, 41080 Seville, Spain. jjortega@irnase.scic.es

The mineralization of phenanthrene in pure cultures of a Pseudomonas fluorescens strain, isolated from soil, was measured in the presence of soil humic fractions and montmorillonite. Humic acid and clay, either separately or in combination, shortened the acclimation phase. A higher mineralization rate was measured in treatments with humic acid at 100 microg/ml. Humic acid at 10 microg/ml stimulated the transformation only in the presence of 10 g of clay per liter. We suggest that sorption of phenanthrene to these soil components may result in a higher concentration of substrate in the vicinity of the bacterial cells and therefore may increase its bioavailability.

UI	MeSH Term	Description	Entries
D010616	Phenanthrenes	POLYCYCLIC AROMATIC HYDROCARBONS composed of three fused BENZENE rings.
D011551	Pseudomonas fluorescens	A species of nonpathogenic fluorescent bacteria found in feces, sewage, soil, and water, and which liquefy gelatin.	Bacillus fluorescens,Bacillus fluorescens liquefaciens,Bacterium fluorescens,Liquidomonas fluorescens
D006812	Humic Substances	Organic matter in a state of advanced decay, after passing through the stages of COMPOST and PEAT and before becoming lignite (COAL). It is composed of a heterogenous mixture of compounds including phenolic radicals and acids that polymerize and are not easily separated nor analyzed. (E.A. Ghabbour & G. Davies, eds. Humic Substances, 2001).	Humic Acid,Humic Acids,Humic Substance,Sodium Huminate,Acid, Humic,Acids, Humic,Huminate, Sodium,Substance, Humic,Substances, Humic
D000077215	Clay	A naturally-occurring rock or soil constituent characterized by particles with a diameter of less than 0.005 mm. It is composed primarily of hydrous aluminum silicates, trace amounts of metal OXIDES, and organic matter.	Halloysite,Clays,Halloysites
D000538	Aluminum Silicates	Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)	Aluminum Silicate,Silicate, Aluminum,Silicates, Aluminum
D001546	Bentonite	A colloidal, hydrated aluminum silicate that swells 12 times its dry size when added to water.	Montmorillonite,Montmorrillonite
D001673	Biodegradation, Environmental	Elimination of ENVIRONMENTAL POLLUTANTS; PESTICIDES and other waste using living organisms, usually involving intervention of environmental or sanitation engineers.	Bioremediation,Phytoremediation,Natural Attenuation, Pollution,Environmental Biodegradation,Pollution Natural Attenuation
D012988	Soil Microbiology	The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.	Microbiology, Soil