ABSTRACT

Heavy metals resistant and polyaromatic hydrocarbon (PAH)-degrading bacteria isolated from Marchica lagoon. Six isolates, Pseudomonas putida, Orchobactrum antropi, Staphylococus epidermidis, Brevundimonas diminuta, Serratia ficaria and Bacillus anthracis were characterized on the basis of biochemical and 16S rDNA. The strains that showed high resistance to heavy metals were also studied for their antibiotics resistance and growth kinetics. The minimal inhibitory concentrations (MIC) of metals at variant concentrations (10-38 mM) were determined in liquid and solid medium. Strains were showed an extreme resistance against metals with the MIC values of Cu (9 mM), Cd (6.25 mM), Cr (2.5 mM), Ag (0,625), and Hg (0,156). Furthermore, growth rates were decreased in the presence of metals (compared to the control). The anthracene elimination from synthetic wastewater was determined in a submerged aerobic fixed-film reactor. Optimal conditions for bacterium growth and biodegradation of anthracene are determined as: temperature of 37 °C, pH 7, and initial anthracene concentration of 20 mg/l. It emerged that at anthracene concentrations 5-40 mg/l, COD removal efficiency were 84.62%; 90.62%; 91.36% and 71.4% respectively.

摘要

从 Marchica 泻湖中分离出的耐重金属和多环芳烃 (PAH) 降解细菌。六个分离株，恶臭假单胞菌、Orchobactrum antropi、Staphylococus epidermidis、Brevundimonas diminuta、Serratia ficaria和Bacillus anthracis在生化和 16S rDNA 的基础上进行了表征。还研究了对重金属表现出高抗性的菌株的抗生素抗性和生长动力学。在液体和固体培养基中测定不同浓度 (10-38 mM) 的金属的最小抑制浓度 (MIC)。菌株对金属表现出极强的抗性，MIC 值为 Cu (9 mM)、Cd (6.25 mM)、Cr (2.5 mM)、Ag (0,625) 和 Hg (0,156)。此外，在金属存在的情况下，增长率降低（与对照相比）。在浸没式好氧固定膜反应器中测定合成废水中蒽的消除。蒽的细菌生长和生物降解的最佳条件确定为：温度为 37 °C，pH 为 7，蒽的初始浓度为 20 mg/l。结果表明，蒽浓度为 5-40 mg/l 时，COD 去除效率为 84.62%；90.62%；分别为 91.36% 和 71.4%。