The results also indicated that cellulose material is suitable carrier to choose in removal of aromatic hydrocarbon contaminated wastewater. These results are considered as new approach to apply microbial films on cellulose material to degrade oil polluted waste-water in the environment. | Journal of Biotechnology 14(4): 769-775, 2016 AROMATIC HYDROCARBON DEGRADATION OF BIOFILM FORMED MICROORGANISMS ON CELLULOSE MATERIAL AT 50 LITRE MODULES BY Le Thi Nhi Cong1,2, Cung Thi Ngoc Mai1, Do Van Tuan2,3, Dong Van Quyen1,2 1 Institute of Biotechnology, Vietnam Academy of Science and Technology Graduate University of Science and Technology, Vietnam Academy of Science and Technology 3 Son La college, Son La city, Vietnam 2 * To whom correspondence should be addressed. E-mail: lenhicong@ Received: Accepted: SUMAMRY Biofilms are defined as community of microorganisms which are irreversibly or reversibly attached on solid surfaces. These microorganisms are embedded in a self-produced exopolysaccharide matrix, and exhibit different growth and bioactivity compared with planktonic cells. With their high biomass density, stability, and potential for biodegradation of recalcitrant compounds contained in oil contaminated wastewater such as aromatic hydrocarbons. Aromatic hydrocarbons are the main constituents of petroleum and its refined products. These compounds are also quantitatively the main environmental pollutants worldwide. In this report, cellulose material was used as a carrier for forming biofilm by microorganisms to remove of these components. Cellulose material is considered as inexpensive, available, sustainable, little waste production and can be recycled. As a result, the microorganisms were successful to adhere on cellulose material at 50 liter module with cell density of CFU/ml after 7 day-incubation. Under the scanning electron microscope with the 1500 magnification, the microbial cells had a very high density, closely linked together and firm adhesion on the cellulose material. The mixture species biofilm attached on cellulose carrier at 50 liter module had the ability to degrade , , , and of anthracene, fluorene, naphthalene, phenol and pyrene after 7 days, respectively. The .