Potential Inhibitor of Adenylyl Sulfate Reductase Isolated from Desulfovibrio desulfuricans with PU/PU-Ag to Control Pitting Corrosion of Oil Tanks and Pipelines

Background and Aims: This study aims to alleviate the microbiologically affected corrosion that occurred by sulfate-reducing bacteria (SRB) through synthesizing a bio-based polyurethane polymer and its nanocomposite coating, silver nanoparticles (PU-Ag). Moreover, it will also evaluate the effect of PU alone and PU-Ag as inhibitors for adenylyl sulfate reductase (APS), the main enzyme for sulfate reduction. Methods: In this study, the PU was prepared from vegetable soybean oil, and the silver nanoparticles (Ag-NPs) with a concentration of 1% were coated to the PU forming a nanocomposite. The PU and the PU-Ag were characterized and evaluated as inhibitors of the APS reductase enzyme. Results: The results obtained from FTIR, UV, DLS, TEM, and XRD confirmed the preparation structure of the PU and PU-Ag. Furthermore, the PU/PU-Ag competitively inhibited the APS reductase with an inhibition constant equal to 35.7 and 11 mg, respectively. These indicated the exerted inhibitory effect of PU/PU-Ag upon the activity of the APS reductase enzyme. Conclusion: The APS reductase enzyme produced by SRB, which is recorded as a big problem in the oil and gas industry such as pitting corrosion of tanks and pipelines, could be inhibited by PU and PU-Ag.