ISSN:
1432-072X
Keywords:
Key words Biosurfactants
;
Pseudomonas
;
Hydrocarbon
;
degradation
;
Hydrocarbon assimilation/uptake
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Pseudomonas maltophilia CSV89, a soil bacterium, produces an extracellular biosurfactant, "Biosur-Pm". The partially purified product is nondialyzable and chemically composed of 50% protein and 12–15% sugar, which indicates the complex nature of Biosur-Pm. It reduces the surface tension of water from 73 to 53 × 10–3 N m–1 and has a critical micellar concentration of 80 mg/l. Compared to aliphatic hydrocarbons, Biosur-Pm shows good activity against aromatic hydrocarbons. The emulsion formed is stable and does not require any metal ions for emulsification. The kinetics of Biosur-Pm production suggest that its synthesis is a growth-associated and pH-dependent process. At pH 7.0, cells produced more Biosur-Pm with less cell surface hydrophobicity. At pH 8.0, however, the cells produced less Biosur-Pm with more cell surface hydrophobicity and showed a twofold higher affinity for aromatic hydrocarbons compared to the cells grown at pH 7.0. The Biosur-Pm showed a pH-dependent release, stimulated growth of the producer strain on mineral salts medium with 1-naphthoic acid when added externally, and facilitated the conversion of salicylate to catechol. All these results suggest that Biosur-Pm is probably a cell-wall component and helps in hydrocarbon assimilation/uptake.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00272131
Permalink