TITLE:
Locally Isolated Bacterial Strains with Multiple Degradation Potential Capabilities on Petroleum Hydrocarbon Pollutants
AUTHORS:
A. Bahobail, S. M. F. Gad El-Rab, G. A. Amin
KEYWORDS:
Biodegradation, Consortium, Multiple Degradation Potentials, Acinetobacter, Bacillus, Pantoea
JOURNAL NAME:
Advances in Microbiology,
Vol.6 No.11,
September
19,
2016
ABSTRACT: In the present study, 23 isolates, dominated by
bacterial genera (74%) were isolated from petroleum sludge at refinery
wastewater plant, Jeddah, KSA, by means of selective enrichment in
nutritionally optimized refinery wastewater (NORWW) and over twelve successive
transfers. Efficiency of biodegradation on complex mixture of hydrocarbons
present in refinery wastewater was evidenced by changes in both total viable counts (TVC) and COD content of cultivation
broth. Out of the 23 isolates three
most potent isolates named BDCC-TUSA-8, BDCC-TUSA-12 and BDCC-TUSA-18
were selected for their efficient COD removal and active growth. The three
isolates were tested separately in Bushnell-Haas (BH) media for their capabilities
to degrade n-Hexadecane, phenol and phenanthrene, representing the major types
of hydrocarbon pollutants. The results strongly indicated that all three
isolates showed multiple degradation
potentials with remarkably fast reaction rates. Before being recommended
for future work, the three isolates were fully characterized and identified employing culture-dependent techniques such as API
20E, API 20NE and API 50CHB, and further confirmed by partial 16S rRNA
gene sequencing and phylogenetic analysis as Pantoea agglomerans, Acinetobacter
lwoffii and Bacillus thuringiensis respectively. The obtained potent
strains provide valuable candidates if assemblages of mixed fewer strains with
overall broad and complementary enzymatic capacities are to be considered in
order to bring the rate and extent of petroleum biodegradation further as a
cost-effective process.