OIL BIODEGRADATION IN THE STRAITS OF MALACCA - PHENANTHRENE DEGRADATION BY AR-3

A phenanthrene-utilizing bacterium (AR-3) was isolated from the sedime nt of Port Dickson coastal waters, Straits of Malacca. The degradation of phenanthrene and a Malaysian crude oil by AR-3 was conducted in a seawater synthetic medium at pH 8 and a salinity of 30 g/liter at 28 d egrees C. Yeast extract (20 mg/liter) was required for growth of AR-3 on phenanthrene and crude oil. Glutamic acid, arginine, or histidine c ould substitute yeast extract for growth on phenanthrene. AR-3 was cap able of growing on degrading the saturated hydrocarbon fraction of a M alaysian crude oil without addition of yeast extract. The degradation of the aromatic hydrocarbon fraction of the crude oil by AR-3 required 20 mg/liter yeast extract. No significant degradation of the asphalte ne hydrocarbon fraction was detected even when 20 mg/liter of yeast ex tract was added. A temperature of 30 degrees C, pH of 8.0, and salinit y of 30 g/liter are the optimal conditions for growth of AR-3 on Malay sian crude oil. Nitrogen rather than phosphorus is the limiting factor in the Straits for oil degradation.