Investigation of bacteria in crude oil after surviving in different sterilization methods and stimulated by different exogenous bacteria

Crude oil was the sole carbon and four sterilizing methods were used for medium and crude oil. The first one "a" was autoclaved at 121 ?C for 20 min. The second one "b" was autoclaved at 121 ?C for 20 min, and then resuscitated at 37 ?C for three days, and autoclaved at 121?C for 20 min at last. The third method "d" was radiative sterilization. The bottles containing medium and crude oil were exposed to 60Co gamma radiation doses of 25 kGy at a speed of 52.08 Gy / min. The last method "f" was parted oil and medium, and then autoclaved at 121?C for 20 min. No sterilization "e" was positive control. The exogenous strains "A" and "B" were Amycolicicoccus sp. DQS3-9A1T and Dietzia sp. DQ12-45-1b, respectively. 0.5% and 5% NaCl concentrations were conducted to DQ12-45-1b, however other treatments were 0.5%. In short, A0.5a, B0.5a, B5a, A0.5b, B0.5b, B5b, A0.5d, B0.5d, B5d, 0.5e, A0.5e, B0.5e, B5e, A0.5f, B0.5f and B5f at 5, 10, 20, 30 day could harvest cells for bacterial analysis. The 10 ml solution of each sample was sacrificed for sampling to collected cells by centrifugation at 8000 rpm for 10 min at 4 ?C. At 30 day, another 10 ml solution of each sample was sacrificed for sampling to extract the total RNA.