Archives of Current Research International

Aims: To determine effects of aromatic hydrocarbons and marine water from Niger Delta on the β-Galactosidase activity mutant Escherichia coli.

Study Design: Fifteen treatments and the control designs were set up in triplicates in microtitre plates containing 200 µL of the 100% concentration of samples (three marine waters and distilled water spiked each with xylene, anthracene and pyrene). The fifteen treatments and control (HgCl₂) set ups designated as A, B, C, D, E, F and G were used to determine their median effective concentration (EC₅₀) for the inhibition of β-Galactosidase activity of mutant Escherichia coli.

Place and Duration of Study: Department of Microbiology, Chukwuemeka Odumegwu Ojukwu University, Uli Nigeria between February, 2017 to July, 2017.

Methodology: A laboratory scale study was carried on the water samples from the three studied areas using physicochemical analyses and bacterial Toxi-chromo test.

Results: The findings revealed that the three sampling sites contain higher quantities of aromatic hydrocarbons, heavy metals and other physico-chemical parameters in the sediment samples than water samples. Xylene distilled water had the highest EC₅₀ of 3.417 ± 0.094 mg/l while pyrene Onne water had the least EC₅₀ of 0.015 ± 0.002 mg /L. Also, pyrene and anthracene are significantly (P = .05) highly toxic aromatic hydrocarbons (EC₅₀ < 1 mg /L) while xylene is a significantly (P = .05) toxic aromatic hydrocarbon (1 mg /L < EC₅₀ ≤ 10 mg /L) compare to the positive control (HgCl₂) (EC₅₀ < 1 mg /L) indicating that enzyme inhibition among test samples were much different from the positive control.

Conclusion: Thus, the toxicity results (< 0.1 mg /L < EC₅₀ ≤ 10 mg /L) in this study indicate that the potential eco-toxicity and environmental health effects of these toxicants should be given attention in order to get rid of their dangerous outcomes.