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Ādampur, India

Chhokar V.,Guru Jambheshwar University of Science and Technology | Sangwan M.,Choudhary Devilal University | Beniwal V.,Guru Jambheshwar University of Science and Technology | Nehra K.,Choudhary Devilal University | Nehra K.S.,Fgm Government College
Applied Biochemistry and Biotechnology | Year: 2010

Tannase from Aspergillus awamori MTCC 9299 was purified using ammonium sulfate precipitation followed by ion-exchange chromatography. A purification fold of 19.5 with 13.5% yield was obtained. Temperature of 30 °C and pH of 5.5 were found optimum for tannase activity. The effects of metals and organic solvents on the activity of tannase were also studied. Metal ions Mg +2, Mn+2, Ca+2, Na+, and K + stimulated the tannase activity, while Cu+2, Fe +3, and Co+2 acted as inhibitors of the enzyme. The addition of organic solvents like acetic acid, isoamylalcohol, chloroform, isopropyl alcohol, and ethanol completely inhibited the enzyme activity. However, butanol and benzene increased the enzyme activity. © 2009 Humana Press. Source

Beniwal V.,Maharishi Markandeshwar University | Nehra K.S.,Fgm Government College | Chhokar V.,Guru Jambheshwar University of Science and Technology
Biocatalysis and Agricultural Biotechnology | Year: 2015

The present study reports the effect of cadmium on lipid composition of developing mustard seeds. The result revealed that the lipid composition was affected appreciably by increasing cadmium doses. Total and non-polar lipids decreased regularly with increasing doses of cadmium (10, 20, 30 and 40ppm). Among total lipids, a positive correlation was found between saturated fatty acid (R2=0.81, palmitic acid; R2=0.71, stearic acid) and cadmium concentration. However, unsaturated fatty acids (R2=0.69, oleic acid; R2=0.89, linoleic acid; R2=0.84, linolenic acid) were found to be decreasing with increasing concentration of cadmium. Cadmium induces increase in palmitic acid (R2=0.82, polar lipids; R2=0.83, non-polar lipids), stearic acid (R2=0.87, polar lipids; R2=0.92, non-polar lipids) and oleic acid (R2=0.66, polar lipids; R2=0.62, non-polar lipids). Cd induced increase in the saturated/unsaturated ratio indicates that either the synthesis or activity of olelyl-CoA desaturase enzyme was affected significantly. © 2015 Elsevier Ltd. Source

Sinha D.,South Asian University | Jain P.,Banasthali University | Siddheshwar P. G.,Bangalore University | Tomer N.S.,Fgm Government College
Journal of Applied Fluid Mechanics | Year: 2016

Steady, transverse boundary layer flow and heat transfer caused by an exponentially stretching cylinder of constant radius immersed in an uniform flow of an incompressible, viscous nanoliquid are considered in the present study. The paper discusses a systematic procedure of obtaining a local similarity transformation that reduces the governing partial differential equations into ordinary differential equations. Power series solution is then obtained for velocity, temperature and nanoparticle concentration distributions using the uni-variate differential transform method. Help is sought from Domb-Sykes plots in making a decision on the minimum number of terms required in the power series expansion to ensure convergence. Radius of convergence is quite naturally suggested by these plots. Padé approximants are then appropriately decided upon to increase the radius of convergence. The algorithm used succeeds in capturing boundary effects, free stream flow effects and nanoparticle effects on flow and heat transfer. An important finding of the paper is the prediction of accelerated cooling of the stretching cylinder due to the nanoparticles in the cooling liquid. In having a desirable property for the extruding cylinder nanoliquid coolant seems an attractive proposition. Source

Chhokar V.,Guru Jambheshwar University of Science and Technology | Seema,Chaudhary Devi Lal University | Beniwal V.,Guru Jambheshwar University of Science and Technology | Salar R.K.,Chaudhary Devi Lal University | And 3 more authors.
Biotechnology and Bioprocess Engineering | Year: 2010

A tannase (E.C. producing fungal strain was isolated from soil and identified as Aspergillus heteromorphus MTCC 8818. Maximum tannase production was achieved on Czapek Dox minimal medium containing 1% tannic acid at a pH of 4.5 and 30°C after 48 h incubation. The crude enzyme was purified by ammonium sulfate precipitation and ion exchange chromatography. Diethylaminoethyl-cellulose column chromatography led to an overall purification of 39.74-fold with a yield of 19.29%. Optimum temperature and pH for tannase activity were 50°C and 5.5 respectively. Metal ions such as Ca2+, Fe2+, Cu1+, and Cu2+ increased tannase activity, whereas Hg2+, Na1+, K1+, Zn 2+, Ag1+, Mg2+, and Cd2+ acted as enzyme inhibitors. Various organic solvents such as isopropanol, isoamyl alcohol, benzene, methanol, ethanol, toluene, and glycerol also inhibited enzyme activity. Among the surfactants and chelators studied, Tween 20, Tween 80, Triton X-100, EDTA, and 1, 10-o-phenanthrolein inhibited tannase activity, whereas sodium lauryl sulfate enhanced tannase activity at 1% (w/v). © 2010 The Korean Society for Biotechnology and Bioengineering and Springer-Verlag Berlin Heidelberg. Source

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