Recent investigations of extreme environments have revealed numerous bioactive natural products. However, biosurfactant-producing strains from deep sea extreme environment are largely unknown. Here, we show that Dietzia maris As-13-3 isolated from deep sea hydrothermal field could produce di-rhamnolipid as biosurfactant. The critical micelle concentration (CMC) of the purified di-rhamnolipid wa...

a rhamnolipid–type biosurfactant production by pseudomonas aeruginosa mm1011 was studied in a miniaturized shaken bioreactor. the operational parameters, affecting the biosurfactant production in shaken bioreactors, such as shaking frequency (200, 250, 300 rpm), filling volume (50, 75, 100 ml), and aeration rate (0.2, 0.6, 1 vvm), were optimized using response surface methodology. the optimizat...

The objective of this research was to evaluate the effect of low concentrations of a rhamnolipid biosurfactant on the in situ biodegradation of hydrocarbon entrapped in a porous matrix. Experiments were performed with sand-packed columns under saturated flow conditions with hexadecane as a model hydrocarbon. Application of biosurfactant concentrations greater than the CMC (the concentration at ...

The biodegradation of hexadecane by five biosurfactant-producing bacterial strains (Pseudomonas aeruginosa UG2, Acinetobacter calcoaceticus RAG1, Rhodococcus erythropolis DSM 43066, R. erythropolis ATCC 19558, and strain BCG112) was determined in the presence and absence of exogenously added biosurfactants. The degradation of hexadecane by P. aeruginosa was stimulated only by the rhamnolipid bi...

A novel rhamnolipid biosurfactant-producing and Polycyclic Aromatic Hydrocarbon (PAH)-degrading bacterium Pseudomonas aeruginosa strain NY3 was isolated from petroleum-contaminated soil samples. Strain NY3 was characterized by its extraordinary capacity to produce structurally diverse rhamnolipids. A total of 25 rhamnolipid components and 37 different parent molecular ions, representing various...

AIMS The effects and extent of adhesion of four different bacterial and two yeast strains isolated from explanted voice prostheses to silicone rubber with and without an adsorbed rhamnolipid biosurfactant layer obtained from Pseudomonasaeruginosa DS10-129 was studied. METHODS AND RESULTS The ability of rhamnolipid biosurfactant to inhibit adhesion of micro-organisms to silicone rubber was inv...

Contaminant sorption within the soil matrix frequently limits biodegradation. However, contaminant bioavailability can be species-specific. This study investigated bioavailability of phenanthrene (PHE) to two PHE-degrading bacteria (Pseudomonas strain R and isolate P5-2) in the presence of rhamnolipid biosurfactant and/or a biosurfactant-producing bacterium, Pseudomonas aeruginosa ATCC 9027. Ps...

In this paper, an air isolate (NITT6L) has been screened based on hemolytic activity, emulsification activity, drop collapsing test, and oil displacement test, as well as lipase activity. It was found that strain NITT6L was able to reduce the surface tension of the medium from 61.5 to 39.83 mN/m and could form stable emulsions with tested vegetable oils. Morphological, biochemical, 16S rRNA seq...

The present study was focused on isolation, screening, characterization and application of biosurfactant producing marine actinobacteria. Twenty actinobacteria were isolated from marine water sample and were primarily screened for biosurfactant production using hemolytic activity method. Among the 20 isolates, six showed positive result for hemolytic activity and those were taken for further se...

Production of a rhamnolipid biosurfactant by cells of Pseudomonas aeruginosa strain BN10 immobilized into poly(ethylene oxide) (PEO) and polyacrylamide (PAAm) cryogels was investigated under semicontinuous shake flask conditions and compared to biosurfactant secretion by free cells. The biosurfactant synthesis was followed over 9 cycles of operation of the immobilized system, each cycle compris...