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Optimization of process variables for a biosorption of nickel(Ⅱ) using response surface method
Shreela Murugesan,Sheeja Rajiv,Murugesan Thanapalan 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.2
The biosorption of nickel(Ⅱ) was studied by using crab shell particles of diameter (dp=0.012 mm) under different initial concentrations of nickel(Ⅱ) in solution (0.01-5.0 g/l), temperature (20-40℃), pH (2-6.5), and biosorbent dosages (0.5-10 g/l). The maximum removal of nickel(Ⅱ) occurred at pH 6.5 and temperature 40℃ for a biosorbent dosage of 6 g/l. The results were modeled by response surface methodology (RSM), which determines the maximum biosorption of nickel(Ⅱ) as a function of the above four independent variables, and the optimum values for the efficient biosorption of nickel(Ⅱ) were obtained. The RSM studies were carried out using Box-Behnken design and the analysis of variance confirms the adequacy of the quadratic model with coefficient of correlation R2 to be 0.9999. The quadratic model fitted the data well with Prob>F to be <0.0001, indicating the applicability of the present proposed model.
Murugesan Manikkampatti Palanisamy,Akilamudhan Palaniyappan,Venkata Ratnam Myneni,Kannan Kandasamy,Padmapriya Veerappan 한양대학교 세라믹연구소 2022 Journal of Ceramic Processing Research Vol.23 No.1
The electronics industry is the world's largest and fastest growing industry. This consumer-centric industry's combination oftechnology advancements and quick product obsolescence creates new environmental issues. There is an urgent need toaddress the volume and toxicity of electronic waste generated. Printed circuit boards (PCBs) are a significant component ofelectronic trash, containing mostly heavy metals such as copper (Cu), tin (Sn), zinc (Zn), and lead (Pb). Metal recovery andrecycling from PCBs is an important step in pollution prevention. Researchers have devised many methods for recoveringprecious metals from PCBs, including gravity separation, magnetic separation, and electrostatic separation, as well as PCBseparation using the organic solvent technique, leaching method, bioleaching method, or a combination of these methods. Thisresearch provides a brief summary of India's present e-waste status, environmental and health risks, continuing waste disposaland recycling activities, and emphasizes the recovery of heavy metals from PCBs by systematic leaching/bioleaching.
Murugesan Manikkampatty Palanisamy,Kannan Kandasamy 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.1
The quantity of electronic waste subjected to disposal annually is increasing alarmingly and is of major environmental concerndue to the existence of heavy metals and other toxic substances. In this present study, by combining leaching and adsorptionthe recovery of heavy metals from Printed circuit boards (PCBs) has been performed. The two stage aqua-regia leachingextracts Copper (Cu), Tin (Sn), Lead (Pb), and Zinc (Zn) from PCB. Bentonite Clay (Bent) and Peanut Shell Carbon (PSC)in their pristine, thermally and chemically activated forms were employed as adsorbents to remove the heavy metals fromleached solution. Effect of parameters (contact time, temperature, adsorbent dosage and size) on % adsorption was studied. Chemically activated bent (C-A Bent) has proven to be an effective among all adsorbents studies with % adsorption for Cu97%, Sn 98%, Zn 96%, and Pb 96%. Leaching and adsorption combination can become a promising methodology for handingelectronic waste.
Murugesan, K.,Nam, I.H.,Kim, Y.M.,Chang, Y.S. IPC Science and Technology Press ; Elsevier Scienc 2007 Enzyme and microbial technology Vol.40 No.7
Dye decolorizing potential of the white rot fungus Ganoderma lucidum KMK2 was demonstrated for recalcitrant textile dyes. G. lucidum produced laccase as the dominant lignolytic enzyme during solid state fermentation (SSF) of wheat bran (WB), a natural lignocellulosic substrate. Crude enzyme shows excellent decolorization activity to anthraquinone dye Remazol Brilliant Blue R (RBBR) without redox mediator whereas diazo dye Remazol Black-5 (RB-5) requires a redox mediator. Polyacrylamide gel electrophoresis (PAGE) of crude enzyme confirms that the laccase enzyme was the major enzyme involved in decolorization of either dyes. Native and SDS-PAGE indicates that the presence of single laccase with molecular weight of 43kDa. N-Hydroxybenzotriazole (HBT) at a concentration of 1mM was found as the best redox mediator. RB-5 (50mgl<SUP>-l</SUP>) was decolorized by 62% and 77.4% within 1 and 2h, respectively by the crude laccase (25Uml<SUP>-1</SUP>). RBBR (50mgl<SUP>-l</SUP>) was decolorized by 90% within 20h, however, it was more efficient in presence of HBT showing 92% decolorization within 2h. Crude laccase showed high thermostability and maximum decolorization activity at 60<SUP>o</SUP>C and pH 4.0. The decolorization was completely inhibited by the laccase inhibitor sodium azide (0.5mM). Enzyme inactivation method is a good method which averts the undesirable color formation in the reaction mixture after decolorization. High thermostability and efficient decolorization suggest that this crude enzyme could be effectively used to decolorize the synthetic dyes from effluents.
Murugesan, C.,Rudramoorthy, R. Korean Society for Fluid machinery 2016 International journal of fluid machinery and syste Vol.9 No.2
This paper focuses on the single stage and multistage performance characteristics of centrifugal mixed flow submersible borewell pump. This study reveals that the performance of single stage pump is higher than that of multistage pumps. The head, input power and efficiency of single stage pump are higher than the per stage head, per stage input power and efficiency of multistage pumps. This study is divided into three parts. In the first part, five prototype pumps were made in single stage and multistage construction and the performance tests were conducted. In the second part, numerical validation has been done for different turbulence models and grid sizes. k-Omega SST model has been selected for the performance simulation and was validated with the performance of the test pump with static pressure tappings. In the third part, single and three stage pump performance were simulated numerically and compared with experimental results. The detailed analysis of pressure and velocity distributions reveals the difference in performance of single and three stage pump, due to non-uniform flow and difference in averaged flow velocities at the subsequent impeller inlets except the 1st stage impeller inlet.
Murugesan, Kumarasamy,Yang, In-Hee,Kim, Young-Mo,Jeon, Jong-Rok,Chang, Yoon-Seok Springer-Verlag 2009 Applied microbiology and biotechnology Vol.82 No.2
<P>In this study, we investigated the efficacy of phenolic extract of wheat bran and lignin-related phenolic compounds as natural redox mediators on laccase-mediated transformation of malachite green (MG) using purified laccase from the white-rot fungus Ganoderma lucidum. G. lucidum laccase was able to decolorize 40.7% MG dye (at 25 mg l(-1)) after 24 h of incubation. Whereas, the addition of phenolic extract of wheat bran enhanced the decolorization significantly (p < 0.001) by two- to threefold than that of purified laccase alone. Among various natural phenolic compounds, acetovanillone, p-coumaric acid, ferulic acid, syringaldehyde, and vanillin were the most efficient mediators, as effective as the synthetic mediator 1-hydroxybenzotriazole. Characterization of MG transformation products by HPLC, UV-Vis, and liquid chromatography-mass spectrometry-electrospray ionization analysis revealed that N-demethylation was the key mechanism of decolorization of MG by laccase. Growth inhibition test based on mycelial growth inhibition of white rot fungus Phanerochaete chrysosporium revealed that treatment with laccase plus natural mediators effectively reduced the growth inhibitory levels of MG than that of untreated one. Among all the tested compounds, syringaldehyde showed the highest enhanced decolorization, as a consequence reduced growth inhibition was observed in syringaldehyde-treated samples. The results of the present study revealed that the natural phenolic compounds could alternatively be used as potential redox mediators for effective laccase-mediated decolorization of MG.</P>
Optimization of Laccase Production from Bacillus sp. PK4 through Statistical Design of Experiments
( Murugesan Rajeswari ),( Vembu Bhuvaneswari ) 한국미생물생명공학회(구 한국산업미생물학회) 2017 한국미생물·생명공학회지 Vol.45 No.4
Statistical design of experiments was employed to optimize the media composition for the production of laccase from Bacillus sp. PK4. In order to find the key ingredients for the best yield of enzyme production from the selected eleven variables viz yeast extract, glucose, zinc sulphate, copper sulphate, potassium chloride, magnesium sulphate, calcium chloride, ferrous sulphate, sodium chloride, potassium dihydrogen phosphate (KH<sub>2</sub>PO<sub>4</sub>) and dipotassium hydrogen phosphate (K<sub>2</sub>HPO<sub>4</sub>), Plackett-Burman design was applied. The MgSO<sub>4</sub>, FeSO<sub>4</sub>, and CuSO<sub>4</sub> showed positive estimate, and their concentration optimized further. The steepest ascent method and Box-Behnken method revealed that 1.5 mM MgSO<sub>4</sub>, 0.33 g/l FeSO<sub>4</sub> and 1.41 mM CuSO<sub>4</sub> were optimal for the laccase production by Bacillus sp. PK4. This optimization strategy leads to enhancement of laccase production from 2.13 U/ml to 40.79 U/ml. Agro-wastes residues replace the carbon source glucose in the optimized media namely sugarcane bagasse, wheat bran, rice husk, and groundnut shell, among these groundnut shells (117 U/ml) was found to enhance the laccase production significantly. The laccase produced by Bacillus sp. PK4 was found to have the potential to degrade persistent organic pollutant benzo[a]pyrene.
Murugesan, Priya,Jung, Birgit,Lee, Dongwon,Khang, Gilson,Doods, Henri,Wu, Dongmei Oxford University Press 2016 The Journal of Infectious Diseases Vol.213 No.4
<P>Background. This study examined the therapeutic effects of an orally active nonpeptide kinin B1 receptor antagonist, BI113823, in a clinically relevant experimental model of polymicrobial sepsis in rats. Methods. Sepsis was induced by cecal ligation and puncture (CLP). Animals received treatment with either vehicle or BI113823. The experiment was terminated in the first set of animals 15 hours after CLP. Seven-day survival following CLP was determined in the second set of animals. Results. Compared with vehicle treatment, administration of BI113823 reduced neutrophil and macrophage infiltration, reduced cytokine production, attenuated intestinal mucosal hyperpermeability, prevented hemodynamic derangement, and improved cardiac output. Furthermore, administration of BI113823 reduced inducible nitric oxide synthase expression and the injury score in the lung and attenuated nuclear factor kappa B activation and apoptosis in the liver. Treatment with BI113823 also reduced plasma levels of cardiac troponin, aspartate aminotransferase, alanine aminotransferase, urea, and lactate, as well as proteinuria. Finally, administration of BI113823 improved the 7-day survival rate following CLP in rats. Conclusions. Administration of BI113823 reduced systemic and tissue inflammatory responses, prevented hemodynamic derangement, attenuated multiorgan injury, and improved overall survival.</P>