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Immobilization Imparts Stability to Watermelon Urease to Work in Water Miscible Organic Media
Om Prakash,Lata Sheo Bachan Upadhyay 한국생물공학회 2006 Biotechnology and Bioprocess Engineering Vol.11 No.2
The behaviour of alginate immobilized and soluble watermelon (Citrullus vulgaris) urease in water miscible organic solvents like, acetonitrile, dimethylformamide (DMF), ethanol, methanol, and propanol is described. The organic solvents exhibited a concentration dependent inhibitory effect on both the immobilized and the soluble urease in the presence of urea. Pretreatment of soluble enzyme preparations with organic solvents in the absence of substrate for 10 min at 30oC led to rapid loss in the activity, while similar pretreatment of immobilized urease with 50% (v/v) of ethanol, propanol, and acetonitrile was ineffective. Time-dependent inactivation of immobilized urease, both in the presence and in the absence of urea, revealed stability for longer duration of time even at very high concen-tration of organic solvents. The soluble enzyme, on the other hand, was rapidly inactivated even at fairly lower concentrations. The results suggest that the immobilization of watermelon urease in cal-cium alginate make it suitable for its application in organic media. The observations are discussed.
Om Prakash Chauhan,Deepak Singh,Vishal Joshi,Garima Singh,Rajendra Kumar Sharma 경남대학교 기초과학연구소 2018 Nonlinear Functional Analysis and Applications Vol.23 No.4
In this article, we define the notion of a non-negative function satisfying property of oneness. Utilizing this concept, certain unified fixed point results are established. Furthermore generalized φ-contractions mapping and some fixed point results in the framework of symmetric space are also presented. Some well-known results from the existence literature are obtained through our introduced setting. Results are substantiated by some innovative examples with the aid of visualization of surfaces. Moreover applications of obtained theory for the existence for the system of integral equations as well as for the system of functional equations occurred in dynamic programming are also presented.
Om Prakash Tiwari,Yashwant Singh Rana,Ram Krishan,Chandra Mohan Sharma,Bhupendra Singh Bhandari 한국산림과학회 2018 Forest Science And Technology Vol.14 No.2
The present study aimed to analyze the regeneration dynamics, population structure, and forest composition in some ridge forests of the Western Himalaya to elucidate the impact of climate change. The highest species richness (trees, 17; saplings, 16; seedlings, 16) was recorded in mixed Rhododendron arboreum forest. The maximum tree density (737 § 25.93 trees ha¡1; mixed Quercus floribunda); sapling density (5342 § 587.54 saplings ha¡1; mixed Quercus semecarpifolia), and seedling density (71,429 § 26,632.29 seedlings ha¡1; mixed Cedrus deodara) were recorded in forests of higher altitudes. The mean basal cover values in these forests oscillated between 39.21 § 1.53 m2 ha¡1 (mixed Quercus leucotrichophora) to 87.65 § 15.45 m2 ha¡1 (mixed Abies pindrow). The highest Shannon index value (0.51 § 0.05) and species evenness (0.36 § 0.02) for trees were recorded in mixed Rhododendron arboreum forest. Some species like Betula utilis, Myrica esculenta, Ficus rumphii, Ilex dipyrena, Quercus floribunda, Litsea elongata, Symplocos paniculata, and Abies spectabilis were noticed as new recruiters (recent invaders) in new habitats, which may change the future forest composition. This study revealed that ridge forests of the Bhagirathi catchment area were in transition phase at middle altitudes. Mixed Quercus floribunda forest was observed to be the youngest regenerating forest; however, mixed Abies pindrow forest was the most mature old-growth forest.
( Om Prakash ),( Seongwon Im ),( Alsayed Mostafa ),( Chungman Moon ),( Dong Hoon Kim ) 한국폐기물자원순환학회(구 한국폐기물학회) 2021 한국폐기물자원순환학회 춘계학술발표논문집 Vol.2021 No.-
The treatment of sulfate rich wastewater leads to the failure of anaerobic digestion process due to high sulfide generation. Sulfide toxicity for the anaerobic digestion process is one the major concern that needs to overcome in order to recover the methanogenic potential of the sulfate-rich wastewater. In the present study, we tried to enhance the sulfide tolerance by promoting direct interspecies electron transfer (DIET) via electrical energy input (EEI). Two different operational conditions have been set to study the effect of sulfide on methanogenic process using up-flow anaerobic sludge blanket (UASB) reactor, comprising one control and one EEI reactor with an applied voltage of 0.6 V. The operation was continued for 194 days under different COD/SO<sub>4</sub> <sup>2-</sup> ratios. The EEI reactor exhibited maximum performance of 2.3 L CH<sub>4</sub>/L/d at the COD/SO<sub>4</sub> <sup>2-</sup> of 5 which is 15 % higher than the control. The free sulfide concentration were 251 and 283 mg S<sup>2-</sup>/L in control and EEI reactors, exceeding the inhibition threshold (50-200 mg S<sup>2-</sup>/L). Only EEI reactor could keep its advanced performance, by acquiring 12 and 15% higher sulfate removal and CH<sub>4</sub> productivity respectively than control reactor. Form this study, it can be claimed that DIET stimulation has potential for enriching efficient sulfate-metabolizing microbes. Furthermore, microbiological studies can enhance the depth of the mechanism and unearthed the reason behind the sulfide tolerance system supported by DIET promoting reactor.
Controlled Release Chitosan Microspheres of Mirtazapine: In Vitro and In Vivo Evaluation
Om Prakash Ranjan,Gopal Venkatesh Shavi,Usha Yogendra Nayak,Karthik Arumugam,Ranjith Kumar Averineni,Pandey Sureshwar,Sreenivasa Reddy Meka 대한약학회 2011 Archives of Pharmacal Research Vol.34 No.11
The purpose of the study was to formulate and evaluate controlled release chitosan microspheres of mirtazapine (MTZ) to improve the bioavailability by altering the pharmacokinetic profiles of the drug. Chitosan microspheres were prepared to prolong the release of the drug into the systemic circulation. Microspheres were prepared by a single water in oil (w/o) emulsion technique varying the chitosan/drug ratio, stirring speed and concentration of the crosslinking agent (glutaraldehyde). Drug-polymer compatibility studies were carried out using fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC). The microspheres were evaluated for encapsulation efficiency, particle size, surface morphology, swelling index, in vitro release, as well as erosion and in vivo studies in rats. The FT-IR and DSC studies revealed no interaction between drug and polymer. The encapsulation efficiency of different formulation varied from 53 ± 1.2% to 78 ± 1.5%. The mean particle size of the optimized formulation F-14 was 106.4 ± 0.5 μm. Surface morphology revealed that chitosan microspheres were discrete and spherical in shape with a porous surface. The release of MTZ from chitosan microspheres was rapid up to 4 h, and then it was continuously and slowly released up to 48 h. Optimized formulation (F-14) was found to be stable under accelerated storage conditions based on International Conference on Harmonisation guidelines. Pharmacokinetic studies revealed that the optimized formulation showed significant increases in systemic exposure (AUC = 177.70 ± 7.39 μg·h/mL), half-life (4.72 ± 0.46 h) and reduced clearance (0.009 ± 0.0001 L/h) compared to pure drug administration. Hence, the present study demonstrates that controlled release formulation of MTZ microspheres using chitosan can improve pharmacokinetic profiles of MTZ.
( Prakash Om ),( Rup Lal ) 한국미생물생명공학회(구 한국산업미생물학회) 2013 한국미생물·생명공학회지 Vol.41 No.1
An unstable yet efficient phenanthrene-degrading bacterium strain Ph-3 was isolated from a petroleum-contaminated site at the Mathura Oil Refinery, India. The strain was identified as Pseudomonas sp. using a polyphasic approach. An analysis of the intermediates and assays of the degradative enzymes from a crude extract of phenanthrene-grown cells showed a novel and previously unreported pattern of 1, 2-dihydroxy naphthalene and salicylic acid production. While strain Ph-3 lost its phenanthrene- degrading potential during successive transfers on a rich medium, it maintained this trait in oligotrophic soil conditions under the stress of the pollutant and degraded phenanthrene efficiently in soil microcosms. Although the maintenance and in vitro study of unstable phenotypes are difficult and such strains are often missed during isolation, purification, and screening, these bacteria constitute a substantial fraction of the microbial community at contaminated sites and play an important role in pollutant degradation during biostimulation or monitored natural attenuation.
Energy management in multi stage evaporator through a steady and dynamic state analysis
Om Prakash Verma,Gaurav Manik,Toufiq Haji Mohammed 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.10
Increasing energy demand, high cost of energy and global warming issues across the globe require energyintensive industries, such as paper mills to improve energy efficiency. Multi-stage evaporators used to concentrate the black liquor in such mills form its most energy consuming unit and require a strong understanding of steady and unsteady state behavior to ensure energy savings. The modeling of nonlinear heptads’ effect system yielded a set of complex nonlinear algebraic and differential equations that are analyzed using Interior-point method and state space representation. Dynamic response of product concentration and system vapor temperatures along with system stability and controllability have been explored by disturbing the flow rate, concentration and temperature of feed, and fresh steam flow rate. Simulations predict that steam flow rate, feed flow rate and its concentration invariably are major controlling factors (in decreasing order) of vapor temperature and product concentration. The interactive behavior between different effects translates into slower responses of the effects with increasing separation from disturbance source. This steady state and transient study opens many new explanations to this relatively less explored area and helps to propose and implement industrial PID controllers to reduce steam consumption and control product quality.