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International Journal of Marine Science, 2017, Vol.7, No.18, 176-182
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2 Results
A total of 65 bacterial isolates of gram negative fermentative and non-fermentative rods was investigated. Fifty six
(86.15%) isolates were correctly identified to the species level, and 9 (13.84%) isolates were not identified. The
direct-identification, reporting time of the Vitek II was 4.5- 10 h after incubation (Table 1).
Table 1 Identified bacteria using Vitek 2
Organism
Correctly identified%
Not identified%
V. vulnificus
15 (98)
9
Sphingomonas paucimobilis
25 (95)
Brevundimonas diminuta/vesicularis
8 (91)
Ochrobactrum anthropic
8
Total
56
9
Four genera were isolated from Khor Al-Zubair channel, southren of Iraq and identified using the Vitek II system
and investigated their ability to degrade crude oil in four concentrations.
Table 2 shows the percentage of degradation of crude oil for each genus.
V. vulnificus
was the most effective
bacteria to degrade crude oil, especially in concentration 2% (93.05%). Meanwhile,
Ochrobactrum anthropi
was
the lowest (9.63%) in concentration 0.25%.
Table 2 Degradation percentage
Bacterial types
Degradation percentage of crude oil (Aliphatic fraction)
0.25%
0.5%
1.0%
2.0%
Vibrio vulnificus
86.49%
83.87%
65.08%
93.05%
Brevundimonas
diminuta/vesicularis
64.61%
81.63%
89.82%
69.15%
Ochrobactrum anthropic
9.63%
51.64%
68.03%
ND
Sphingomonas paucimobilis
79.19%
58.31%
78.19%
67.00%
The concentrations of normal-alkanes located between C9 and C28 with isopernoids-pristine and phytane were
calculated by comparing with standard solutions. Figure 2 shows gas chromatography results of n-alkanes of
control sample (0.25%). Biodegradation of n-alkanes by
V. vulnificus
after 7 days were shown in the results of gas
chromatography (Figure 3) and the biodegradation percentage was 86.49% (Table 1). Figure 4 shows the gas
chromatography results of crude oil incubated with
Brevundimonas diminuta/vesicularis
and the biodegradation
percentage was 64.61% (Table 1). While Figure 5 and Figure 6 show the gas chromatography results of n-alkanes
of crude oil incubated with
Ochrobactrum anthropic
and
Sphingomonas paucimobilis
and the biodegradation
percentage were 9.63% and 79.19% respectively.
Figure 2 Crude oil (aliphatic fraction) 0.25%
Figure 3 Crude oil 0.25% with
V.vulnificus
