Enhancement of hydrocarbon waste biodegradation by the addition of a biosurfactant from Bacillus subtilis O9.

ANA MORÁN,; NELDA LILA OLIVERA; MARTA COMMENDATORE,; LUIS ESTEVES, JOSÉ; FAUTINO SIÑERIZ,

Biodegradation

Springer

Lugar: Holanda; Año: 2000 vol. 11 p. 65 - 71

A non-sterile biosurfactant preparation (surfactin) obtained from a 24-h culture of Bacillus subtilis O9 grown on sucrose was used to study the effect on the biodegradation of hydrocarbon wastes by an indigenous microbial community at Erlenmeyer flask scale. Crude biosurfactant was added to the cultures to obtain concentrations above and below the critical micelle concentration (CMC). Lower concentration affected nither biodegradation nor microbial growth, whereas with the higher concentration, the exponential phase of growth extended from 24 to 72 h, reaching higher cell concentrations. Biodegradation of aliphatic hydrocarbons increased from 20.9 to 35.5 % and in the case of aromatic hydrocarbons from nil to 41 %, respect to the culture without biosurfactant. The enhancement effect of  biosurfactant addition was more noticeable in the case of long chain alkanes. Pristane and phytane isoprenoids were degraded to the same extent as n-C17 and n-C18 alkanes and, consequently, no decrease in the ratios n-C17/pri and n-C18/phy was observed. This biosurfactant could be useful for the bioremediation of hydrocarbon contaminated sites.