Production of Rhamnolipid by Pseudomonas aeroginosa in Media containing Treated Whey

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.