ABSTRACT
Abstract Carbaryl is an important and widely used insecticide that pollutes soil and water systems. Bacteria from the local soil ecosystem of the Gaza Strip capable of utilizing carbaryl as the sole source of carbon and nitrogen were isolated and identified as belonging to Bacillus, Morganella, Pseudomonas, Aeromonas and Corynebacterium genera. Carbaryl biodegradation by Bacillus, Morganella and Corynebacterium isolates was analyzed in minimal liquid media supplemented with carbaryl as the only source of carbon and nitrogen. Bacillus and Morganella exhibited 94.6% and 87.3% carbaryl degradation, respectively, while Corynebacterium showed only moderate carbaryl degradation at 48.8%. These results indicate that bacterial isolates from a local soil ecosystem in the Gaza Strip are able to degrade carbaryl and can be used to decrease the risk of environmental contamination by this insecticide.
Subject(s)
Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Bacteria/metabolism , Biodegradation, Environmental/classification , Biodegradation, Environmental/genetics , Biodegradation, Environmental/isolation & purification , Biodegradation, Environmental/metabolism , Carbaryl/classification , Carbaryl/genetics , Carbaryl/isolation & purification , Carbaryl/metabolism , Ecosystem/classification , Ecosystem/genetics , Ecosystem/isolation & purification , Ecosystem/metabolism , Insecticides/classification , Insecticides/genetics , Insecticides/isolation & purification , Insecticides/metabolism , Middle East/classification , Middle East/genetics , Middle East/isolation & purification , Middle East/metabolism , Soil Microbiology/classification , Soil Microbiology/genetics , Soil Microbiology/isolation & purification , Soil Microbiology/metabolism , Soil Pollutants/classification , Soil Pollutants/genetics , Soil Pollutants/isolation & purification , Soil Pollutants/metabolismABSTRACT
Histoplasma capsulatum is a soil fungus with a wide geographic distribution. It has not only been isolated repeatedly from soil specimens but both its micro- and macroconidia have been demonstrated in soil, air, and water. The occurrence of these spores in nature unequivocally proves that H. camsulatum actively grows and multiplies in soil as a saprophyte and does not merely reside there in a passive state. This conclusion is based on the fact that conidia are not produced by H. capsulatum in its parasitic phase
Ecological studies carried out in Williamson County, Tennessee, with Zeidberg during the period of 1952-1955, first revealed that H. capsulatum is not uniformly distributed in nature. It was found that chicken habitats favored the development of this mold. Soil samples collected at random yielded few isolates of H. capsulatum, while specimens collected in and around chicken yards, especially chicken coops, gave a higher percentage of positive cultures
Chickens are not the sole species of birds associated with H. camsulatum habitats. It has been recovered from sites enriched with the dung of grackles (Ouscalus quiscula), oil birds (Steatornis caripensis), pigeons (Columba livia), and starlings (Surnus vulgaris)
Avian habitats or soil obtained from such areas and transported elsewhere have been incriminated on numerous occasions as the source of outbreaks of acute pulmonary histop. ...(AU)
