The sulphate-reducing bacteria (SRB) isolated from Bach Ho oil well (H strain), Thi Nai pond sediments in Quy Nhon (6C) was used to evaluate the degradability of crude oil and oil products. The oil samples were treated by specific strains and their combination. It was shown that after 3 to 7 weeks of treatment these strains degraded up to 36 - 57% of residual oil, 7 - 12% of crude oil and 19 - 21% of fuel oil (FO) in the medium. The oil degradability of all samples increased 3 - 12% in the present of biosurfactants compared to the case without adding biosurfactants.
