Abstract: | The Lewis acidity of yttrium and dysprosium exchanged zeolite Y and ZSM-5 has been determined by titration method using Hammett indicators. The acidity of the Y form increases with increase in concentration of the rare earth cation in the Y zeolite. It is independent of the amount of the rare earth ion for ZSM-5. The data have been correlated with the activity of these zeolites for the esterification of butanol using acetic acid. |
URI: | http://dyuthi.cusat.ac.in/purl/2310 |
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Dyuthi-SS77.pdf | (173.7Kb) |
Abstract: | The present study is about the Pseudomonas sp. BTMS-51 isolated from the marine sediments of Cochin Coast. In the present study, it is concluded that marine bacteria are ideal candidates for immobilization using either Ca-alginate entrapment or physical adsorption on to synthetic inert supports and the process of immobilization does not negatively influence them. Thus, Ca-alginate entrapment of the bacteria was found to be well suited for reuse of the biomass and extended operational stability during continuous operation. Adherence of the bacterium to inertsupports was observed to be strong and it imparted minimal stress on the immobilized bacterium and allowed detachment and relocation on the supports which enabled the formation of a dynamic equilibrium maintaining a stable cell loading. This is particularly desirable in the industry for extended operational stability and maintenance of consistently higher outputs. Marine Pseudomonas sp. BTMS-51 is ideal for industrial production of extra cellular L-glutaminase and immobilization on to synthetic inert support such as polyurethane foam could be an efficient technique, employing packed bed reactor for continuous production of the enzyme. Temperature and glutamine concentration had significant effects on enzyme production by cells immobilized on polyurethane foam (PUF). |
URI: | http://dyuthi.cusat.ac.in/purl/930 |
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Dyuthi-T0194.pdf | (6.904Mb) |
Abstract: | L-glutaminases (L—glutamine amidohydrolase EC.3.5.l.2) is proposed as a prospective candidate for enzyme therapy cnf cancer and also as zui important additive during enzymatic digestion of shoyu koji since it could enhance glutamate content of soysauce. Commercial production of glutaminase could make possible its wide application in these areas, which would demand availability of potential sources and suitable fermentation techniques. The ‘present investigation highlighted marine environment as a potential source of efficient glutaminase producing bacteria mainly species of pseudomonas, aeromonas ,vibrio,alcaligenes, acinetobacter bacillus and planococci.Among them pseudomonas fluorescens ACMR 267 and v.cholerae ACMR 347 were chosen as the ideal strains for glutaminase production.Extracellular glutaminase fraction from all strains were in higher titres than intracellular enzymes during growth in mineral media, nutrient broth and nutrient broth added with glutamine.Glutaminase from all strains were purified employing (NH4)2SO4 fractionation followed tnr dialysis and ion exchange chromatography. The purified glutaminase from all strains were observed to be active and stable over a wide range of gfii and temperature.Optimization studies cflf environmental variables that normally influence time yiehi of glutaminase indicated that the optimal requirements of these bacteria for maximal glutaminase production remained stable irrespective of the medium, they are provided with for enzyme production. However, solid state fermentation technique was observed to be the most suitable process for the production of Glutaminase. |
Description: | Department of Applied Chemistry, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3106 |
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Dyuthi-T1080.pdf | (5.045Mb) |
Abstract: | Extracellular L-glutaminase production by Beau6eria sp., isolated from marine sediment, was observed during solid state fermentation using polystyrene as an inert support. Maximal enzyme production (49.89 U:ml) occurred at pH 9.0, 27°C, in a seawater based medium supplemented with L-glutamine (0.25% w:v) as substrate and D-glucose (0.5% w:v) as additional carbon source, after 96 h of incubation. Enzyme production was growth associated. Results indicate scope for production of salt tolerant L-glutaminase using this marine fungus |
Description: | Process Biochemistry 35 (2000) 705–710 |
URI: | http://dyuthi.cusat.ac.in/purl/4241 |
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L-Glutaminase p ... lid state fermentation.pdf | (310.7Kb) |
Abstract: | This study presents the L-Glutaminase Production by Marine Fungi. Enzymes are involved in all aspects of biochemical conversion from the simple enzyme or fermentation conversion to the complex techniques in genetic engineering. Enzyme industry is one among the major industries of the world and there exists a great market for enzymes in general. Food industry is recognized as the largest consumer for commercial enzymes (Lon sane and Ramakrishna, 1989). In industry, enzymes are frequently used for process improvement, for instance to enable the utilization of new types of raw materials or for improving the physical properties of a material so that it can be more easily processed. They are the focal point of biotechnological processe. The marine biosphere is one of the richest of the earth's innumerable habitats, yet is one of the least well characterized. The marine biosphere covers more than two third of the world's surface, our knowledge of marine microorganisms, in particular fungi, is still very limited (Molitoris and Schumann, 1986). The results obtained in the present study the following conclusions are drawn. Beauveria bassiana isolated form marine sediment has immense potential as an Industrial organism for production of L-glutaminase as an extracellular enzyme employing either submerged fermentnation or solid state fermentation |
URI: | http://dyuthi.cusat.ac.in/purl/1006 |
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Dyuthi-T0197.pdf | (2.454Mb) |
Abstract: | Use of inert supports have been recommended for SSF in on ar to overcome its inherent problems and efforts are being made to search for newer and better materials to act as inert solid supports lidoo et al, 1982; Zhu et al, 1994).In the present study an attempt is made to produce L-glutaminase, which is industrially and therapeutically impo rtant, from marine bacteria under solid state fermentation using natura.l. inert and mixed substrates with a view to develop an ideal bioprocess for its large scale production. |
Description: | Microbial Technology Unit, Department of Biotechnology, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3370 |
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Dyuthi-T1347.pdf | (6.136Mb) |
Abstract: | The work embodied in this thesis was carried out by the author in the Department of Applied Chemistry, CUSAT, Kochi, during the period 2008-2013. The thesis brings to light, our attempts to evaluate the coordination behavior of some compounds of interest. The biological activities of semicarbazones and their metal complexes have been an active area of research during the past years because of their significant role in naturally occurring biological systems. Tridentate NNO and ONO semicarbazone systems formed from heterocyclic and aromatic carbonyl compounds and their transition metal complexes are well-authenticated compounds in this field and their synthesis, crystal structures and spectral studies are well desirable. Hence, we decided to develop a research program aimed at the syntheses, crystal structures and spectral studies of copper complexes with halides and pseudohalides. In addition to single crystal X-ray diffraction studies, various physico-chemical methods of analysis were also used for the characterization of the complexes |
Description: | Department Of Applied Chemistry Cochin University Of Science And Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3537 |
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Dyuthi-T1506.pdf | (15.76Mb) |
Abstract: | Semicarbazones and their transition metal complexes have been receiving considerable attention because of their biological relevance and applications in the field of analysis and in the field of organic NLO materials. Their structural diversity also attracted inorganic chemists. A good deal of work has been reported on the synthesis and structural investigation of semicarbazones and their complexes. This is due partially to their capability of acting as multidentate, NO, NNO, ONO and ONNO donors with the formation of either mono or bi or polynuclear complexes. Their chemistry and pharmacological applications have been extensively investigated. Appreciable biological applications as well as diverse stereochemistry of their metal complexes prompted us to synthesize two new tridentate ONO donor N4-phenyl semicarbazones derived from 2-hydroxy-4-methoxyacetophenone and 2-hydroxy-4-methoxybenzophenone and their transition metal complexes. These ketones were selected since they can provide a further binding site from phenolic–OH and can thus increase the denticity. Introduction of heterocyclic bases like 1,10-phenanthroline, 2,2′-bipyridine, 4,4′-dimethyl- 2,2′-bipyridine and 4-picoline and some pseudohalides like azide and thiocyanate ion can result in mixed ligand metal chelates with different geometries in coordination compounds In the present study, oxovanadium(IV), manganese(II), cobalt (II/III), nickel(II), copper(II) and zinc(II) complexes of 2-hydroxy-4- methoxyacetophenone-N4-phenylsemicarbazone (H2ASC) and 2-hydroxy-4- methoxybenzophenone-N4-phenylsemicarbazone (H2BSC) were synthesized and characterized. |
Description: | Department of Applied Chemistry, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/3426 |
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Dyuthi-T1412.pdf | (26.39Mb) |
Abstract: | We report unusual spectral narrowing and laser emission from polymer thin films doped with Coumarin 540 dye. The laser emission from the polymer films is found to be highly dependent upon the excitation length of the medium. Even a short length of 1.75 mm of the dye doped film gave rise to laser emission with FWHM of 0.3 nm for a pump intensity of 825 kW cm−2. The partial reflections from the broad lateral surfaces of the free standing films provided the optical feedback for the laser emission. Occurrence of well-resolved equally spaced resonant modes confirmed the effect of a Fabry–Perot-like optical cavity between the film surfaces. |
URI: | http://dyuthi.cusat.ac.in/purl/2420 |
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Dyuthi-P0267.pdf | (421.1Kb) |
Abstract: | We report unusual spectral narrowing and laser emission from polymer thin films doped with Coumarin 540 dye. The laser emission from the polymer films is found to be highly dependent upon the excitation length of the medium. Even a short length of 1.75 mm of the dye doped film gave rise to laser emission with FWHM of 0.3 nm for a pump intensity of 825 kW cm−2. The partial reflections from the broad lateral surfaces of the free standing films provided the optical feedback for the laser emission. Occurrence of well-resolved equally spaced resonant modes confirmed the effect of a Fabry–Perot-like optical cavity between the film surfaces |
URI: | http://dyuthi.cusat.ac.in/purl/1789 |
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Light amplification in dye doped polymer.pdf | (402.1Kb) |
Abstract: | Coir pith black liquor obtained as a dark brown filtrate from oxidative delignification needs to be decolourised before releasing to open environment. From this liquor industrially valuable lignin was recovered using acid precipitation method. ‘Biochar’ was produced by slow pyrolysis of coir pith at 500oC and 600oC. Water holding capacity and pH of the biochar were estimated. CHNS analysis was carried out to identify the nutrient profile. Structural characterization was done using FTIR and SEM Studies. Biochar produced at 600oC was found to be more suitable for decolourisation of the coir pith black liquor. FTIR analysis indicated peak changes while SEM analysis indicated surface area and porosity changes. Biochar decolourisation experiments were carried out on crude coir pith black liquor and also on lignin recovered coir pith black liquor. |
Description: | Research Journal of Recent Sciences Vol. 1 (ISC-2011), 270-274 (2012) |
URI: | http://dyuthi.cusat.ac.in/purl/4066 |
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Lignin recovery ... Coir pith Black Liquor.pdf | (375.5Kb) |
Abstract: | We present the spectral and nonlinear optical properties of ZnO-SiO2 nanocomposites prepared by colloidal chemical synthesis. Obvious enhancement of ultraviolet (UV) emission of the samples is observed, and the strongest UV emission of a typical ZnO-SiO2 nanocomposite is over three times stronger than that of pure ZnO. The nonlinearity of the silica colloid is low, and its nonlinear response can be improved by making composites with ZnO. These nanocomposites show self-defocusing nonlinearity and good nonlinear absorption behavior. The observed nonlinear absorption is explained through two photon absorption followed by weak free carrier absorption and nonlinear scattering. The nonlinear refractive index and the nonlinear absorption increase with increasing ZnO volume fraction and can be attributed to the enhancement of exciton oscillator strength. ZnO-SiO2 is a potential nanocomposite material for the UV light emission and for the development of nonlinear optical devices with a relatively small limiting threshold. |
URI: | http://dyuthi.cusat.ac.in/purl/2608 |
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Dyuthi-P0168.pdf | (705.0Kb) |
Abstract: | Various compositions of linear low density polyethylene(LLDPE) containing bio-filler(either starch or dextrin)of various particle sizes were prepared.The mechanical,thermal,FTIR,morphological(SEM),water absorption and melt flow(MFI) studies were carried out.Biodegradability of the compositions were determined using a shake culture flask containing amylase producing bacteria(vibrios),which were isolated from marine benthic environment and by soil burial test. The effect of low quantities of metal oxides and metal stearate as pro-oxidants in LLDPE and in the LLDPE-biofiller compositions was established by exposing the samples to ultraviolet light.The combination of bio-filler and a pro-oxidant improves the degradation of linear low density polyethylene.The maleation of LLDPE improves the compatibility of the c blend components and thepro-oxidants enhance the photodegradability of the compatibilised blends.The responsibility studies on the partially biodegradable LLDPE containing bio-fillers and pro-oxidants suggest that the blends could be repeatedly reprocessed without deterioration in mechanical properties. |
Description: | Dept.of Polymer Science and Rubber Technology,Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/2938 |
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Dyuthi-T0929.pdf | (2.327Mb) |
Abstract: | In this paper, the generation of a multiwavelength laser source from a Brillouin -Erbium fiber laser in the long wavelength band (L-band) region is experimentally demonstrated. The proposed laser system utilizes a Fabrv-Perot cavity formed by fiber-loop mirrors. Twenty-four lines of Brillouin-Stokes with line spacings of 10 GHz are obtained in the L-band region |
URI: | http://dyuthi.cusat.ac.in/purl/1419 |
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Line of brillou ... perot cavity in L-band.PDF | (759.9Kb) |
URI: | http://dyuthi.cusat.ac.in/purl/5476 |
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Dyuthi T-2515.pdf | (5.220Mb) |
Abstract: | The Indian ornamental fish industry is divided into two- the domestic market and the export market. 90% of the freshwater ornamental fish exported from India are wild caught indigenous species. The study formed the criteria and indicators assessing the sustainability of wild caught ornamental fish exported from India. These indicators were then analyzed for their interactions, connections, linkages and relationships using cognitive mapping. The work is first of its kind in the ornamental fisheries |
Description: | International Journal of Environmental Sciences Volume 3 No.6, 2013 |
URI: | http://dyuthi.cusat.ac.in/purl/4129 |
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Linking sustain ... namental fish industry.pdf | (352.0Kb) |
Abstract: | ABSTRACT: Linseed oil is used in the dual roles of the plasticizer and the fatty acid component of the activator in nitrile rubber vulcanizates. The study shows that the substitution can substantially improve the mechanical properties in addition to other advantages such as increased cure rate, reduced leachability and reduced compound cost. |
URI: | http://dyuthi.cusat.ac.in/purl/850 |
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V Nandanan and others,Linseed oil..,1996.PDF | (4.764Mb) |
Abstract: | Marine fungus BTMFW032, isolated from seawater and identified as Aspergillus awamori, was observed to produce an extracellular lipase, which could reduce 92% fat and oil content in the effluent laden with oil. In this study, medium for lipase production under submerged fermentation was optimized statistically employing response surface method toward maximal enzyme production. Medium with soyabean meal- 0.77% (w/v); (NH4)2SO4-0.1 M; KH2PO4-0.05 M; rice bran oil-2% (v/v); CaCl2-0.05 M; PEG 6000-0.05% (w/v); NaCl-1% (w/v); inoculum-1% (v/v); pH 3.0; incubation temperature 35 8C and incubation period-five days were identified as optimal conditions for maximal lipase production. The time course experiment under optimized condition, after statistical modeling, indicated that enzyme production commenced after 36 hours of incubation and reached a maximum after 96 hours (495.0 U/ml), whereas maximal specific activity of enzyme was recorded at 108 hours (1164.63 U/mg protein). After optimization an overall 4.6- fold increase in lipase production was achieved. Partial purification by (NH4)2SO4 precipitation and ion exchange chromatography resulted in 33.7% final yield. The lipase was noted to have a molecular mass of 90 kDa and optimal activity at pH 7 and 40 8C. Results indicated the scope for potential application of this marine fungal lipase in bioremediation. |
Description: | New Biotechnology Volume 28, Number 6 October 2011 |
URI: | http://dyuthi.cusat.ac.in/purl/4250 |
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Lipase from mar ... oil effluent treatment.pdf | (940.8Kb) |
Abstract: | Strain improvement is one of the major objectives for maximizing the microbial production of industrially significant primary and secondary metabolites. This goal can be achieved by judicious tuning of the organisms by monitoring its growth parameters and optimizing adequate supply of micro and macro nutrients, inducers, pH, temperature and other factors which control fermentation. Though C. rugosa has been under extensive studies for lipases, maximum world production is only 36 units. In fact, in India, enhanced production conditions for lipases have not yet been initiated. C. rugosa has been cultivated in diverse environments like liquid, semi-solid, solid—state and immobilized conditions, though major emphasis is on SmF or suspension culture. Hence the present investigations mainly focused on increasing the yield by adjusting the physico-chemical growth parameters and to characterize the lipase isoforms secreted by C. rugosa in the culture medium. Maximum possible improved methods were investigated to achieve these objectives. Within this under-optimised background, enhancement of lipase production and its characterization were investigated, employing modified liquid, semi-solid, solid—state and immobilized fermentation strategies |
Description: | Biotechnology Division Regional Research Laboratory Trivandrum |
URI: | http://dyuthi.cusat.ac.in/purl/3599 |
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Dyuthi-T1594.pdf | (7.106Mb) |
Abstract: | The present study indicate the scope for the utilization of the marine fungus Aspergillus awamori Nagazawa BTMFW 032 for extracellular lipase production employing submerged fermentation. To the best of our knowledge this is the first report on lipase production by a marine fungus employing statistical modeling towards industrial production. The characterization of purified lipase produced by A. awamori showed stability in organic solvents, oxidizing agent and reducing agents, I,3-regiospecificity and hydrolytic activity. These properties make this lipase an ideal candidate for biocatalysis in organic media for the production of novel compounds such as biodiesel and sugar fatty esters. 91.4 % reduction in oil and grease content in ayurvedic oil by the treatment of A. awamori lipase indicates that there is a scope for this enzyme in the treatment of oil effluents and bioremediation. There is ample scope for further research on the biochemistry of the enzyme, structure elucidation and enzyme engineering towards a wide range of further applications, besides enriching scientific knowledge on marine enzymes. |
Description: | Department of Biotechnology, Cochin University of Science and Technology |
URI: | http://dyuthi.cusat.ac.in/purl/2730 |
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Dyuthi-T0765.pdf | (8.449Mb) |
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