Marine oil spills have bad impacts on the marine biota. Oil spill mitigation that is currently safe, effi cient, relatively cheap and easy to implement is bioremediation, that is degradation of oil spills biologically using microorganisms. Petroleum will be more easily dispersed in water when surfactants are added. The surfactants have the ability to increase the bioavailability of petroleum to facilitate bacteria contact with carbon sources as their feed. This study was intended to test the effect of addition of diethanolamide (DEA) surfactants to improve the ability of bacteria to degrade hydrocarbon compound in the seawater media. The biodegradation experiment was conducted in 8-liter seawater media and the ability of DEA surfactants to reduce surface tension, oil content, pH and nutrients on days 0, 1, 3, 6 and 10 were observed. GC-MS analysis was conducted to detect chemical component changes in petroleum. A bacterial consortium of Enterobacter sp., Pseudomonas sp., and Raoultella sp. was utilized. The oil was degraded up to 65.52% with biodegradation rate k = -0.1054 t in the media added with DEA surfactants. The aliphatic fraction detected was C17-C31 n-alkane compound and after biodegradation it became C20- C31. The results showed that DEA surfactants were able to improve the ability of bacterial consortium to degrade petroleum.

Pencemaran minyak bumi semakin banyak terjadi dengan semakin meningkatnya permintaan minyak untuk dunia industri, meningkatnya jumlah anjungan pengeboran minyak lepas pantai, dan meningkatnya transportasi laut. Beberapa cara penanggulangan tumpahan minyak meliputi penanggulangan mekanis, pembakaran in situ, kimiawi, dan bioremediasi. Bioremediasi adalah penggunaan makhluk hidup, khususnya mikroorganisme untuk mendegradasi atau mendetoksifikasi pencemar lingkungan. Mikroorganisme yang digunakan dapat berupa bakteri alami yang berasal dari daerah yang tercemar maupun bakteri yang diisolasi dari daerah lain lalu diintroduksi ke daerah yang tercemar. Penelitian ini bertujuan menguji kemampuan bakteri laut dalam mendegradasi minyak menggunakan media yang berbeda, yaitu antara media seawater nutrient broth dan media air terformasi, serta menyimulasikan proses degradasi minyak yang mengalami dispersi dalam sebuah microcosm Penelitian ini merupakan peningkatan skala dari penelitian Dwinovantyo (2015) dan modifikasi dari penelitian Cappello et al. (2006) dan Darmayati et al (2015). Simulasi degradasi tumpahan minyak dilakukan menggunakan media bervolume 8 liter berisi air laut yang tercemar tumpahan minyak, kemudian dilakukan pengamatan populasi bakteri serta kandungan tumpahan minyak. Bakteri yang digunakan adalah konsorsium dari Raoultella sp., Pseudomonas sp., dan Enterobacter sp. yang berasal dari sedimen laut dalam hasil isolasi dan identifikasi Dwinovantyo (2015).

Marine oil spills have bad impacts on the marine biota. Oil spill mitigation that is currently safe, effi cient, relatively cheap and easy to implement is bioremediation, that is degradation of oil spills biologically using microorganisms. Petroleum will be more easily dispersed in water when surfactants are added. The surfactants have the ability to increase the bioavailability of petroleum to facilitate bacteria contact with carbon sources as their feed. This study was intended to test the effect of addition of diethanolamide (DEA) surfactants to improve the ability of bacteria to degrade hydrocarbon compound in the seawater media. The biodegradation experiment was conducted in 8-liter seawater media and the ability of DEA surfactants to reduce surface tension, oil content, pH and nutrients on days 0, 1, 3, 6 and 10 were observed. GC-MS analysis was conducted to detect chemical component changes in petroleum. A bacterial consortium of Enterobacter sp., Pseudomonas sp., and Raoultella sp. was utilized. The oil was degraded up to 65.52% with biodegradation rate k = -0.1054 t in the media added with DEA surfactants. The aliphatic fraction detected was C17-C31 n-alkane compound and after biodegradation it became C20- C31. The results showed that DEA surfactants were able to improve the ability of bacterial consortium to degrade petroleum.