Faculty Publications

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    Eclipta prostrata leaf aqueous extract mediated synthesis of titanium dioxide nanoparticles
    (2012) Govindasamy, G.; Rahuman, A.A.; Priyamvada, B.; Khanna, V.G.; Devarepally, D.K.; Jose, P.J.
    Eco-friendly, nontoxic, inexpensive, abundantly available hitherto unreported Eclipta prostrata leaf extract is used for the biosynthesis of titanium dioxide nanoparticles (TiO 2 NPs). The TiO 2 NPs were characterized by FTIR, XRD, AFM and FESEM analysis. FTIR peak implicated the role of carboxyl group OH stretching amine NH stretch in the formation of TiO 2 NPs. XRD characterized in crystallographic plane of rutile phase. AFM showed uneven surface morphology which indicates the presence of both individual and agglomerated nanoparticles. FESEM analysis showed shape in spherical clusters, quite polydisperse and it ranges in size from 36 to 68 nm with calculated average size of 49.5 nm. In this paper, we have demonstrated a novel biological route for the synthesis of TiO 2 NPs. © 2011 Elsevier B.V. All rights reserved.
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    Partitioning studies of glutaminase in polyethylene glycol and salt-based aqueous two-phase systems
    (2013) Bolar, S.; Belur, P.D.; Iyyaswami, I.
    The partitioning behavior of glutaminase produced from Zygosaccharomyces rouxii in polyethylene glycol (PEG)-salt aqueous two-phase systems (ATPSs) was investigated. ATPSs comprising of different PEG-salts were considered. Binodal data and tie lines generated for the selected systems were analyzed and correlated with Othmer-Tobias and Bancroft equations. Effects of salt type, PEG molecular weight, concentrations of phase components, and tie line length on enzyme partitioning were evaluated. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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    Partitioning studies of ?-lactalbumin in environmental friendly poly (ethylene glycol) - Citrate salt aqueous two phase systems
    (2013) Kalaivani, S.; Iyyaswami, I.
    Aqueous two-phase systems (ATPS) formed by polymer and salt have been utilized to enrich the desired biomolecule into one of the phase with higher yield and purity. The eco-friendly, biodegradable poly ethylene glycol (PEG) and different citrate salts were chosen as ATPS phase components to investigate the partitioning behavior of ?-lactalbumin (?-La). System factors and process parameters such as type and concentration of salt, molecular weight and concentration of PEG, pH, temperature and the effect of additives were studied and the results are discussed in detail. PEG 1000-tri-potassium citrate system yields high partition coefficient of 20 with a better yield of 98 % in the top phase. The addition of NaCl as an additive and acidic pH lowers the yield of ?-La in the top phase. Influence of phase volume ratio (V r) on partitioning was studied and found that the partition coefficient remains almost constant along the tie line. High yield was achieved at a V r of 3.5 at the tie line length of 50.63 (%, w/w). © 2013 Springer-Verlag Berlin Heidelberg.
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    Solvent extraction of molybdenum(VI) from acidic solution by fatty methylhydrazide
    (2013) Sadhi, M.S.; Wardham, D.
    Fatty methylhydrazides were used to extract molybdenum(VI) from hydrochloric acid in hexane. The extraction process has been investigated under different conditions. It was found that the extraction of molybdenum(VI) at low aqueous acidity ([HCl] ? 2 mmol mL-1) is governed by a cation exchange reaction and higher acidity ([HCl] ? 2 mmol mL-1) by a solvating reaction. This work presents the development of a low-cost and environmentally friendly extractant to recycle and recover molybdenum. © 2012 Springer Science+Business Media Dordrecht.
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    1-Hexyl-3-Methylimidazolium Chloride-Potassium Carbonate Aqueous Two Phase System: Equilibrium Characteristics and BSA Partitioning Behavior
    (Taylor and Francis Inc. 325 Chestnut St, Suite 800 Philadelphia PA 19106, 2014) Iyyaswami, I.; Monteiro, S.L.
    The partitioning behavior of the model protein (bovine serum albumin) was investigated in ionic liquid (1-hexyl-3-methylimidazolium chloride) -salt (potassium carbonate) based aqueous two phase system (ATPS). The phase diagram with binodal curve and tie lines for the selected ATPS was developed at different temperatures and analyzed through effective excluded volume (EEV) and Othmer-Tobias and Bancroft equations, respectively. The influence of various process parameters like the ionic liquid and salt concentration, system temperature, tie line length, phase volume ratio, and neutral salt addition on partition coefficient/extraction efficiency of BSA protein was evaluated. © 2014 Copyright Taylor & Francis Group, LLC.
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    An optimization study of microwave assisted extraction of oil from oily sludge using response surface methodology
    (CAFET INNOVA Technical Society cafetinnova@gmail.com 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2014) Kumar, B.; Raj Mohan, B.
    Petroleum oily sludge, a hazardous waste, generated by the refineries and at the production sites in huge quantities comprises of a mixture of petroleum hydrocarbons, asphaltenes, long chain paraffinic wax, waste water, sediments and metals. The present study is aimed to recover oil from the petroleum oily sludge using n-heptane as the solvent in microwave assisted solvent extraction process and to optimize the process variables for the recovery of oil from the oily sludge. The simultaneous effects of process variables such as irradiation time (2 - 10 minutes), solvent to sludge ratio (40 – 80 wt %), reactant volume (100 – 300 ml) and microwave power (80 – 400 W) on the recovery of oil were evaluated. A central composite design (CCD) and response surface methodology (RSM) were used for the optimization of the extraction process. Based on the CCD, quadratic model was developed to correlate the extraction process variables with the responses and the model was analysed using appropriate statistical method (ANOVA). Optimization of process variables shows that the maximum recovery of oil was about 88.6% at 100 ml of reactant volume with microwave power output of 351 W at 6.5 minutes of irradiation time with 58.99% of nheptane to sludge ratio. © 2014 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.
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    Recovery and Partial Purification of Bovine ?-Lactalbumin from Whey Using PEG 1000 – Trisdoium Citrate Systems
    (Taylor and Francis Inc. 325 Chestnut St, Suite 800 Philadelphia PA 19106, 2015) Sivakumar, K.; Iyyaswami, R.
    The extraction of ?-Lactalbumin (?-La) and ?-Lactoglobulin (?-Lg) from whey have been carried out in the Aqueous Two Phase System (ATPS) composed of PEG 1000 – tri sodium citrate. The suitable conditions for the simultaneous partitioning of ?-La into the top phase and ?-Lg in bottom phases was identified using the pure ?-La and ?-Lg. Maximum partition coefficient (k) of 16.67 was achieved for ?-La at the system condition of 28% (w/w) PEG 1000-14% (w/w) tri sodium citrate at pH 8 and 40°C, whereas in this condition k of ?-Lg is 0.27. 30% (w/w) whey loaded to this system yielded the maximum recovery of ?-La and ?-Lg. © , Copyright © Taylor & Francis Group, LLC.
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    Synergistic extraction of ?-Lactalbumin and ?-Lactoglobulin from acid whey using aqueous biphasic system: Process evaluation and optimization
    (Elsevier, 2015) Kalaivani, S.; Iyyaswami, R.
    The present investigation focused on the simultaneous partitioning of ?-Lactalbumin (?-La) to the PEG rich phase and ?-Lactoglobulin (?-Lg) to the salt rich bottom phase from acid whey using polyethylene glycol 1000-trisodium citrate systems. The effect of Tie Line Length (TLL), pH, volume ratio and whey concentration on the proteins partitioning was evaluated. Further the Response Surface Methodology (RSM) was employed to analyze the synergistic and interactive effect of these variables (TLL, pH and whey loading) on the responses (recovery and purity of ?-La and ?-Lg). Optimum values of these variables were obtained for different goals through desirability based multi response optimization. A system of 54.12% (w/w) TLL with 30.6% (w/w) whey at pH 7.23 separates ?-La with 89% recovery and purity of 96% in the top phase, whereas that of ?-Lg in the bottom phase was 96% and 76% respectively. © 2015 Elsevier B.V.
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    Purification of Glutaminase from Zygosaccharomyces rouxii in Polyethylene Glycol– Sodium Sulphate Aqueous Two-Phase System
    (Taylor and Francis Inc. 325 Chestnut St, Suite 800 Philadelphia PA 19106, 2015) Bolar, S.; Iyyaswami, R.; Belur, P.D.
    L-glutaminase (EC 3.5.1.2) produced from Zygosaccharomyces rouxii NRRL-Y 2547 was partitioned in an aqueous two phase system comprising PEG 2000 and sodium sulphate. The effects of tie line length (TLL), pH, broth loading (BL), volume ratio, and neutral salt concentration on enzyme partitioning and purification were investigated. The optimal condition for the partitioning of glutaminase was obtained through response surface methodology and obtained the partition coefficient and yield of 12.99 and 95.12%, respectively. The purification factor of 5.59 and selectivity of 6.52 were achieved at the optimal condition. © © Taylor & Francis Group, LLC.
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    Aqueous two phase partitioning of fish proteins: partitioning studies and ATPS evaluation
    (Springer India sanjiv.goswami@springer.co.in, 2015) Nagaraja, V.H.; Iyyaswami, R.
    A suitable Aqueous Two Phase System (ATPS) has been identified for the partitioning of crude fish proteins from fish processing industrial effluent. A detailed study has been performed to analyze the influence of various parameters on protein partitioning such as molecular weight of PEG, effect of different salts (MgSO4, K2HPO4, Na3C6H5O7, Na2SO4, (NH4) 2PO4, K3C6H5O7) and their concentrations, pH, temperature, Tie Line Length (TLL), effluent loading and volume ratio. PEG 2000 - sodium sulphate ATPS was found to be a most favourable system among the selected ATPS for higher partition coefficient of proteins. The binodal curve and equilibrium characteristics of PEG 2000 - sodium sulphate were established and fitted to empirical equations. The equilibrium compositions (tie line) were correlated using Othmer–Tobias and Bancroft equations. © 2014, Association of Food Scientists & Technologists (India).