Comparison of selenite (IV) and selenate (VI) effect on some oxidoreductive enzymes in soil contaminated with spent engine oil

Abstract

This paper assesses the impact of spent engine oil on activity of dehydrogenase, nitrate reductase, catalase and o-diphenol oxidase in sandy soil, and evaluates biostimulation with selenates in the restoration of homeostasis of soil with spent engine oil. The experiment was carried out on loamy sand samples with organic carbon content of 8.71 g/kg, with the following variable factors: dose of spent engine oil: 0, 2, 10, 50 g/kg dry matter (DM) of soil; selenate application: without selenate, selenite (IV) and selenate (VI) in the amount of 0.05 mmol/kg DM of soil; day of experiment: 1, 7, 14, 28, 56, 112. Obtained results showed that spent engine oil increased activity of dehydrogenase and catalase. Application of selenite (IV) and selenate (VI) to soil non-contaminated with spent engine oil stimulated activity of dehydrogenase and nitrate reductase and inhibited in o-diphenol oxidase. Among selenates tested regarding biostimulation of oxidoreductases in soil contained spent engine, selenate (VI) is more useful than selenite (IV).

Keywords

• petroleum hydrocarbons
• soil enzymes
• selenium
• remediation