Abstract:
Indigenous bacteria play vital roles in the bioremediation of crude oil polluted soils. The effectiveness of the bioremediation process depends on the tolerance, characteristics and biodiversity of the bacteria isolates. Bacteria strains were isolated from crude-oil polluted sites in different locations in the southern region of Nigeria namely: Azikoro and Otukpoti (Bayelsa state); Ologbo and Benin (Edo State) and non-polluted soil was collected from Ibadan (Oyo state). Tolerance study was conducted for 96 h s. Isolation and characterization of the most effective isolate from each location was done using cultural, physico-chemical and molecular methods. The tolerance level of the isolates from the different oil-polluted soils and their comparative growth performance on crude oil supplemented media decreases in the order: Azikoro - Ologbo - Otukpoti - Benin. MATS analysis showed that cell surfaces of Azikoro, Ologbo and Otukpoti strains exhibited 58-63 % adhesion to n-hexadecane and are hydrophobic strains while Benin strain possess 38% adhesion to n-hexadecane and are hydrophilic. The cell surfaces of isolates from Azikoro, Ologbo and Otukpoti are highly Lewis-acidic while that from Benin is highly Lewis-basic. Isolates from Benin-3, Ologbo-1, and Otukpoti-1 were shown to be gram positive while that from Azikoro was gram negative. 16S rDNA fingerprinting confirmed the identities of the isolates as follows: Paenalcaligenes suwonesis with accession numbers NR-133804.1 from Azikoro spillage site (93.77%); Lactobacillus nagelii with accession number NR-158108.1 (91.30%) from Benin spillage site; Lactobacillus fermentum with accession number NR-104927.1 (96.70%) from Ologbo and Otukpoti spillage sites. Phylogenetic analysis putatively categorized the isolates from Otukpoti and Ologbo in close association belonging to same homology while Benin isolate is a subgroup. The characteristics and biodiversity of all the isolated bacteria from the regions possibly justifies their involvement in the bioremediation of petroleum hydrocarbons.
摘要:
土著细菌在原油污染土壤的生物修复中起着至关重要的作用。生物修复过程的有效性取决于耐受性,细菌分离株的特征和生物多样性。从尼日利亚南部地区不同地点的原油污染地点分离出细菌菌株:Azikoro和Otukpoti(巴耶尔萨州);Ologbo和贝宁(江户州),从伊巴丹(奥约州)收集无污染的土壤。耐受性研究进行了96小时。从每个位置分离和表征最有效的分离是使用文化,物理化学和分子方法。来自不同石油污染土壤的分离株的耐受性水平及其在补充原油的培养基上的比较生长性能按以下顺序降低:Azikoro-Ologbo-Otukpoti-贝宁。MATS分析表明Azikoro的细胞表面,Ologbo和Otukpoti菌株对正十六烷具有58-63%的粘附力,并且是疏水性菌株,而贝宁菌株对正十六烷具有38%的粘附力,并且是亲水性的。Azikoro分离物的细胞表面,Ologbo和Otukpoti是高度Lewis酸性的,而贝宁的是高度Lewis碱性的。来自贝宁-3,Ologbo-1和Otukpoti-1的分离株显示为革兰氏阳性,而来自Azikoro的分离株为革兰氏阴性。16SrDNA指纹图谱确认了分离株的身份如下:来自Azikoro溢出位点的登录号为NR-133804.1的Paenalcaligenessuwonesis(93.77%);来自贝宁溢出位点的登录号为NR-158108.1(91.30%)的纳氏乳杆菌;来自Ospillo的登录号为NR-104927.1(96.70%)系统发育分析推定将Otukpoti和Ologbo的分离株分类为密切相关,属于相同的同源性,而贝宁分离株是一个亚组。来自该地区的所有分离细菌的特征和生物多样性可能证明了它们参与石油烃的生物修复的合理性。