Biosurfactant production by Phialemonium sp. using agroindustrial wastes: influence of culture conditions

Biosurfactant are surface active compounds with emulsifying capacity and are produced by microorganisms, and they may be affected by factors related to microbial cultivation, such as pH, salinity, incubation time, carbon and nitrogen sources. The aim of this work was to study the influence of the culture conditions on the production of biosurfactants by Phialemonium sp using agroindustrial wastes. The processing parameters of temperature, humidity and pH produced the most significant effects on the production of biosurfactant and emulsifying activity. The maximum concentration of biosurfactant obtained in this study was equivalent to a surface tension reduction of 8.5 mg L-1 surfactin commercial solution using wheat bran, pH of 4.5, and 0.5% of soybean oil added at 30°C. Under these conditions, 83.4 EU g-1 of emulsifying activity, 16.4 g L-1 of emulsifier index and 18.3 U g-1 lipolytic capacity were obtained.

Synergestic Effect of pour point depressants and surfactant on the properties of crude oil fractions

The mutual interaction of asphaltene and wax fraction of high waxy crude oil were studied using infrared spectroscopy. Two pour point depressant were prepared by copolymerization of vinyl acetate and maleic anhydride then esterification of the copolymer obtained with tetradecyl / octadecyl alcohol [A and B] respectively. Nonionic surfactant was synthesized by alkylation of coal-tar phenol with dodecyl alcohol then reacting the alkyl phenol with formaldhyde and amine to produce the Mannish base. The Mannich base product was reacted with polyethylene glycol molecular weight [Mol.wt.] 4000 to produce the surfactant [C]. The synthesized products were characteristic by determination infrared spectral analysis and molecular weight. It was found that by adding the complex ABC or its components A, B, or AB to the crude very nice result in reducing the pour point at different concentration obtained. It has been shown from the research result of infrared spectrum of interaction between ABC at 1000 ppm or its compounds and wax or Asphaltene isolated from the crude that cocrystallization may be a primary factor in reducing the pour point of the crude, The position of the infrared absorption peak of asphaltene moved to lower wave number

Determination of cultural conditions for the production of rhamnolipid biosurfactant by pseudomonas aeruginosa RB 28

The ability of [20] bacterial isolates of the genus Pseudomonas isolates was tested to produce biosurfactant using crude oil as carbon source. P.aeruginosa RB28 was selected for its high ability to produce biosurfactant. The optimal conditions for production of biosurfactant from RB 28 strain were studied, the results showed that sunflower oil [4%], urea [6g/l], Mg[++] [0.5g/I], Fe[++] [0.008 g/1], Ca[++] [0.05g/l], pH 7.0 and temperature between 30-34 °C after 60 hours of incubation. The maximum production of rharnnolipid [7g/l] was obtained after using these optimum conditions