in this study 152 bacterial strains were isolated from the contaminated oils in the southwest of iran. hemolysis was used as a criterion for the primary  isolation of biosurfactant producing-bacteria. fifty five strains had haemolytic activity , among them tweleve strains were good biosurfactant producers by measuring surface tension and emulsification activity.two microorganism showed the high...

By considering the fact that the surface tension of a real fluid arises from a combination of both repulsive and attractive forces between molecules, a new expression for the interfacial tension has been derived from scaled particle theory (SPT)  based on the work of cavity formation and the interaction energy between molecules. At the critical temperature, the interfacial tension between c...

Through this study, the ability of a modified Peng-Robinson (MPR) equation of state in predicting the surface tension of n-alkanes based on the density functional theory approach was investigated and compared with other studies. The interfacial layer thickness and the density profile were calculated simultaneously at different temperatures from triple point to near critical point using the modi...

A Pseudomonas aeruginosa mutant derived by random mutagenesis with N-methyl-N¢-nitro-N-nitrosoguanidine, producing high levels of the rhamnolipid biosurfactants was selected on Siegmund-Wagner (SW) plates. The mutant designated P. aeruginosa PTCC1637 produces rhamnolipids at concentrations 10 time more than parent strain. NMR analysis and surface tension measurement showed that the biosurfactan...

conclusions potato peels were proved to be potentially useful substrates for biosurfactant production by b. pumilus dsvp18. the strain possessed a unique property to reduce surface tension of the media from 72 to 28.7 mn/m. in addition, it showed a stable surface activity over a wide range of temperatures, ph, and saline conditions and had strong antimicrobial activity. this potential of the id...

In this study 152 bacterial strains were isolated from the contaminated oils in the southwest of Iran. Hemolysis was used as a criterion for the primary  isolation of biosurfactant producing-bacteria. Fifty five strains had haemolytic activity , among them tweleve strains were good biosurfactant producers by measuring surface tension and emulsification activity.Two microorganism showe...

a pseudomonas aeruginosa mutant derived by random mutagenesis with n-methyl-n¢-nitro-n-nitrosoguanidine, producing high levels of the rhamnolipid biosurfactants was selected on siegmund-wagner (sw) plates. the mutant designated p. aeruginosa ptcc1637 produces rhamnolipids at concentrations 10 time more than parent strain. nmr analysis and surface tension measurement showed that the biosurfactan...

acanthophyllum laxiusculum is one of the most widely distributed species of the genus in iran that flourishes in steppe and mountainous regions of the country. in the present study, water-soluble content of a. laxiusculum roots was extracted by boiling water and further successively purified partially by a defined solvent system. surface tension measurements revealed the ability of plant extrac...