Showing 4 results for Rhamnolipid
Volume 8, Issue 4 (11-2010)
Abstract
Biosurfactants are surface active agents which are widely used in industries. One of the important varieties of biosurfactants are widely produced by Pseudomonas aeruginosa. In this paper. P. aeruginosa MM1011 was obtained from Persian Type Culture Collection (Biotechnology Department, IROST). The aim of this investigation is to optimize the mineral salts medium with whey to produce rhamnolipid. Since P. aeruginosa is Lac (-), the whey hydrolysed by lactase in order to produc glucose as carbon source. The results assayed by phenol-sulfuric acid method and crude oil emulsification activity. Depicted results showed that the best medium is 3M which contained whey (that hydrolysed by lactase completely at temp.: 40° C ,pH: 6.5, time: 3 hours) . The product obtained at temp.: 33 ° C, pH:7, shaking rate: 200 rpm , nitrogen concentration, 0.36 %, and inoculum size, 2 %. The results of rhamnolipid production by usig whey as a source of carbon and energy is more or less comparable with the results obtained when molasses was used as carbon and energy source.
Volume 9, Issue 3 (10-2010)
Abstract
Biosurfactants are products of broad range of microorganisms. These compounds are surface active. Glycolipids, Phospholipids & Fatty acids, Lipopeptids and Lipoproteins, Polymeric biosurfactants and Special Biosurfactants are main types of biosurfactants. Rhamnolipid is a type of Glycolipids that is produced by Pseudomonas aeruginosa. In the present paper, P. aeruginosa MM1011 was obtained from Persian Type Culture Collection (Biotechnology Center, IROST). The aim of this investigation was optimization of mineral salts medium with sugar beet molasses to produce rhamnolipid considering specific parameters. such as: C/N, Temperature, pH, shaking rate, and Inoculation size. Since P. aeruginosa is Suc.(-), it was mutated to be able to use the sucrose as carbon source. The molasses treated chemically, then used by the bacterium. The results assayed by phenol-sulfuric acid method, and crude oil emulsification capability. Results of ANOVA. Depicted results showd that the optimum conditions without molasses is: temp.:33˚c, pH 7, C/N:18, shaking rate: 200 rpm and inoculom: 2% in 96 hours and the best medium is 3M which contained sugar beet molasses. Further investigation proved that the best production temperature is 33°c when pH is 6.8, shaking rate: 200 rpm, C/N: 16, inoculom: 2%. Using the above mentioned factors, the obtained results showed that the produced rhamnose was 0.22 g/L (rhamnolipid = 0.66 g /L) and crude oil emulcification was 55.5 %.
H Amani,
Volume 14, Issue 1 (4-2014)
Abstract
The petroleum industry generates large amounts of solid and semisolid wastes known as oily sludges. Oily sludges can be generated in several steps of the petroleum production and refining in the bottom of tanks. The accumulation of oily residues in petroleum industry poses aserious environmental problem.The aim of this research was to evaluate an alternative process of removal of oily sludge from storage tanks that can be carried out by using biosurfactants. One of the most important properties of biosurfactants is reduction of surface tension and formation of oil/water emulsions. In this research, the ability of Pseudomonas aeruginosa PTCC 1570 to produce rhamnolipid was shown and the production of rhamnoilipd was confirmed by TLC and HPLC analysis. The rhamnolipid production started at exponential growth phase and continued during the stationary phase. During investigation of rhamnolipid production on sunflower oil as sole carbon, the results showed that the maximum rhamnolipid reached about 0.5 g/l. Finally, crude oil recovery from an oil storage tank using produced rhamnolipd was also demonstrated at CMC concentration. An oil recovery of up to 70 % was obtained in a storage tank using this method.
H Amani,
Volume 14, Issue 4 (6-2015)
Abstract
In this research, the ability of Pseudomonas aeruginosa NP2to produce rhamnolipid biosurfactant was investigated. Rhamnolipid has various applications in oil industry including cleaning oil sludge filters, cleaning oil storage tanks and biological treatment of oil wastes.The purpose of this paper was optimization of biosurfactant production for reduction of costs using taguchi experimental design methods. Source of carbon, salt concentration, phosphorus concentration and nitrogen concentration at three levels were investigated. The best condition for biosurfactant production was observed when sucrose was used as carbon source, 50 g/l Nacl as salt source, 6.75 g/l NaH2PO4 as phosphorus source, and 1g/l (NH4)2SO4 as nitrogen source. The highest rhamnoliopd production among different experiments was 2.8 g/l. Also the evaluation of emulsification index (E24) of the produced rhamnolipid was studied and the emulsification index value of 80% was reached for crude oil (API=34).
