Faculty Publications

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    Anionic surfactant based reverse micellar extraction of l-asparaginase synthesized by Azotobacter vinelandii
    (Springer Verlag, 2017) Murugesan, S.; Iyyaswami, R.; Kumar, S.V.; Surendran, A.
    Abstract: l-Asparaginase synthesized by Azotobacter vinelandii via submerged fermentation in the presence of sucrose was successfully extracted using Reverse micellar extraction. Single step enzyme purification process was developed by varying the process variables which resulted in maximum specificity and extraction of l-asparaginase. The effect of different variables, including broth pH, addition of alcohol during the forward extraction and pH of the fresh stripping aqueous phase, addition of alcohol and electrolyte during backward extraction process were studied. Lower concentration of butanol resulted in maximum activity of the enzyme during forward extraction while enzyme activity was found to increase further with the addition of higher concentrations of ammonium sulphate during backward extraction. Chromatographic analysis of l-asparaginase peak at ~7.65 min was intense for the back extracted sample confirming the maximum purity of l-asparaginase obtained. Purity of l-asparaginase was increased to about 379.68 fold. Graphical abstract: [Figure not available: see fulltext.]. © 2017, Springer-Verlag Berlin Heidelberg.
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    Performance of anionic dimeric surfactant on AZ31 Magnesium alloy in neutral medium unveiled through experimental and theoretical investigation
    (Springer, 2024) Acharya, M.G.; Nityananda Shetty, A.N.
    The synthesis of a novel eco-friendly anionic Gemini surfactant, pursuing three parameters of green chemistry: economic, environmental factor, and mass reaction efficiency is developed as a corrosion inhibitor for AZ31 Mg alloy. Herein, the corrosion inhibition ability of novel EDTA-based dimeric surfactant on AZ31 Mg alloy in corrosive media with varying concentrations of NaCl and Na2SO4 at temperatures between 30–50 °C were studied. The surfactant’s molecular structure is affirmed by FT-IR, NMR, and LC–MS techniques. Electrochemical techniques and surface morphology were employed to evaluate the corrosion inhibition efficiency. The inhibitor studied exhibited appreciable corrosion inhibition at 30 °C. The surfactant shows physical adsorption as per the data obtained in the Gibbs free energy and enthalpy of adsorption studies. The adsorption of the inhibitor was found to be a film-like layer on the surface of AZ31 Mg alloy and, is confirmed by SEM–EDX and XPS techniques. In addition, theoretical simulations were performed to compare with experimental results. Conclusively, the work provides a deeper understanding of the intricacies involved in the development of a new anionic dimeric surfactant as an effective corrosion inhibitor. © The Author(s) 2024.