Faculty Publications
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Item 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.Item Enhancement of n-3 polyunsaturated fatty acid glycerides in Sardine oil by a bioimprinted cross-linked Candida rugosa lipase(Elsevier Inc. usjcs@elsevier.com, 2018) Sampath, C.; Belur, P.D.; Iyyaswami, R.Considering the advantages of bioimprinting and carrier free immobilization, cross-linked enzyme aggregates (CLEA) were prepared by using bioimprinted Candida rugosa lipase (CRL) with Bovine serum albumin (BSA), Polyethyleneimine and glutaraldehyde. Effect of various factors such as CRL-Oleic acid ratio, CRL-BSA ratio, CRL- Polyethyleneimine ratio, glutaraldehyde loading, cross-linking time etc., on lipase activity recovery and aggregate yield were studied and optimized. This immobilized lipase (CRL-CLEA) was used for the selective hydrolysis of ester linkages of non-PUFA glycerides, with an aim to concentrate EPA and DHA glycerides in the Sardine oil. Imprinting with oleic acid in the presence of ethanol and Tween 60, and further immobilization with co-aggregates and cross-linking agent showed 10.4 times higher degree of hydrolysis compared to free enzyme. As result, 2.83-fold increase of n-3 PUFA content in deacidified oil was obtained by using CRL-CLEA. The resultant oil had negligible di- and triglycerides content, proving higher efficiency in hydrolysing ester bonds of fatty acids, other than n-3 PUFA. Reusability studies showed CRL-CLEA could be reused up to 5 runs without a substantial reduction in its performance. Improvement in degree of hydrolysis, thermostability, efficiency of hydrolysis and reusability were achieved due to bioimprinting and subsequent immobilization of CRL in the form of CLEA. © 2017 Elsevier Inc.Item Simultaneous partitioning of multiple bioactive compounds from Garcinia indica rinds in a three-liquid-phase extraction systems(Taylor and Francis Ltd., 2025) Shanbhag, C.C.; Salimuddin, R.M.H.; Iyyaswami, R.; Belur, P.D.Simultaneous extraction and purification of principal bioactive compounds, anthocyanins (ACNs), garcinol (GL), and hydroxycitric acid (HCA) from the rinds of Garcinia indica (Kokum) fruits in a single-step using Three Liquid Phase Systems (TLPS) were investigated. Among the various phase-forming components studied, TLPS formed by n-hexane-ethanol-(NH4)2SO4-water system was considered for partitioning GL into the n-hexane-rich top phase, ACNs into the ethanol-rich middle phase, and HCA into the aqueous salt-rich bottom phase. The present system was even able to separate carbohydrates into the bottom phase, which can be detrimental to the stability of ACNs. The effect of n-hexane, ethanol, and (NH4)2SO4 concentration on the partitioning behavior of biomolecules was analyzed. The TLPS composed of water-n-hexane-ethanol-(NH4)2SO4 could purify and extract 95.08% of ACNs, 95.33% of GL, and 67.98% of HCA in a single-step extraction process while the other extraction methods require multi-step extraction process to separate these three compounds. The effect of pH studies on the partitioning characteristics of biomolecules revealed that pH 4 is optimum and more efficient than the native pH of the system to achieve maximum yield of all the bioactive compounds. © 2025 Taylor & Francis Group, LLC.