Screening surfactant producer native bacteria from Chiapas state using used oil cooking

Abstract

The used oil cooking was used as a carbon source for the generation of microbial biosurfactants, this products are tensioactives that can be applied for treatment of polluted environments with persistent organic compounds. The screening of nine strains of native bacteria strains from Chiapas state was made in agar selective medium of mineral salts medium and methylene blue by detecting of bacterial strains forming halo growth of methyl white. The bacterial strains selected were cultured in liquid medium with used oil cooking 2 % v/v as only carbon source in 125 mL Erlenmeyer flasks, cultivation was carried out at environment temperature with 120 rpm agitation for 144 h. Tensoactive properties were quantified during the experiment. The bacterial strains C and D, reduced surface tension to a minimum value of 27.0 mN/m and 27.4 mN/m respectively, while bacterial strains A, B and 83 had emulsion index values higher to 20%. It is concluded that native bacterial strains produce biosurfactants using as substrate used cooking oil and have the ability to produce it.