Degradation of different hydrocarbons and production of biosurfactant byPseudomonas aeruginosa isolated from coastal waters

Abstract

A bacterium isolated from an oil spillage sample and identified asPseudomonas aeruginosa degraded hexadecane and heptadecane by 47% and 58% with 9% and 12% of total carbon from the respective substrates being liberated as CO2. With octadecane and nonadecane as substrates, 73% and 60% were biodegraded while 27% and 25% of total carbon was evolved as CO2, respectively. Production of biosurfactant by this bacterium was studied using hexadecane 5% (v/v) as substrate. The surface tension of spent culture medium, as well as the supernatant, was 30 mN/m compared to 71 mN/m for water. When the supernatant was mixed with hexadecane (1∶5, v/v) a stable emulsion was formed which deteriorated only by 10% after one month.