Isolation and Characterization of Halotolerant Aerobic Bacteria From Oil Reservoir

Abstract

Beberapa bakteria halotoleran telah berjaya dipencilkan daripada sampel air masin telaga minyak Semangkok di mana ujian biokimia dan morfologi telah dijalankan bagi bakteria ini. Hampir semua bakteria yang dipencilkan tergolong di dalam genus Bacillus. Sebahagian besar daripada pencilan berkeupayaan untuk hidup di dalam medium pertumbuhan yang mengandungi kerosen sebagai sumber karbon utama dan tenaga dan berkeupayaan untuk hidup di dalam medium dengan kepekatan NaCI diantara 10–15%. Ujian ketegangan antara permukaan (IFT) menunjukkan pencilan menghasilkan biosurfaktan. Enam daripada sembilan pencilan menghasilkan eksopolisakarida di dalam medium pertumbuhan yang mungkin penting di dalam MEOR. Kata kunci: Bakteria; pencirian; pengasingan; Surfaktan; Eksopolisakarida Several halotolerant bacteria were isolated from brine samples from Semangkok oil reservoir. Biochemical and morphological characterization of the bacteria were carried out. These bacteria are gram positive spore formers and have been identified as belonging to the genus Bacillus. Most of the isolates could grow in medium containing kerosene as sole carbon source and energy and tolerate NaCI concentration up to 15%. Interfacial tension and surface tension tests showed that the bacteria were capable of producing biosurfactant. Six out of nine were able to produce exopolysaccharide. We believe these isolate could be appointed as future biopolymer producer especially for microbial enhanced oil recovery (MEOR). Keywords: Bacteria; Characterization; Isolation; Surfactant; Exopolysaccharides.