02241nab a2200217 4500 20260520002814.0 260224s2008 xxu Biosurfactants production from low cost substrate and degradation of diesel oil by a rhodococcus strain nov./dic. 2008 15/05/2009 ; 24/02/2009 6 p. ; 747-753 Transcripción del resúmen publicado por el autor: The ability of a Rhodococcus strain to produce surface-active agents from residual sunflower frying oil (RSFO) has been screened in batch cultures. During cultivation with RSFO at the concentration 3% (vol/vol), the strain has synthesized extra-cellular compounds which increase the E24 emulsion index of the culture medium up to 63%. In their crude form, these substances lower the surface tension of water until 31.9 mN m-1. The exponential growth with RSFO as the sole carbon source has developed at a specific growth rate = 0.55 d-1. The critical micelle concentration of the crude product reached the value 287 mg L-1 (CMC = 31.9 mN m-1). After methylesterification, the lipid fraction of biosurfactants has been analyzed by GC-MS in EI, which reveals the presence of fatty acid methyl esters. The microorganism was also cultivated with the diesel oil as the sole carbon source at the concentration 1% (vol/vol): the active growth phase has developed at rate = 0.02 d-1, without production of emulsifying substance: the microorganism seems to develop different modes of substrate uptake, according to the nature of the carbon source. The potential use of surface-active agents synthesized on RSFO by Rhodococcus erythropolis 16 LM.USTHB is in the oil industry with minimum purity specification, so that crude preparation could be used, at low cost, in clean-up of hydrocarbons contaminated sites and for enhanced oil recovery. 6 63 Oil and Gas Science and Technology ARTICULO Sadouk, Z. 40388 Hacene, H. 40389 Tazerouti, A. 40390 169124 169124 http://ogst.ifp.fr/index.php?option=article&access=standard&Itemid=129&url=/articles/ogst/pdf/2008/06/ogst08015.pdf 0 0 0 0 236943 BVIAPG BVIAPG 2026-03-05 200043916 0 200043916 2026-03-05 15:11:20 2026-03-05 ARTICULO