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Genetic Manipulation Of Tomato (Lycopersicon Esculentum) Using Wga Gene Through Agrobacterium Mediated Transformation
Get PDFThe major problems faced in the field of Agriculture are loss in crop yield caused by insects, Herbs (weeds), viruses and the pathogens and the pests associated loss is about 14% of total agricultural production. The use of pesticides has resulted in adverse effect on the beneficial organisms and other plant parts such as leaves, fruits and has reached pollution levels, which has become a major concern for environmentalists. Therefore, products of crops resistant to insects have been the first priority in crop biotechnology. Genetic transformation has led the possibility of transforming crops for enhanced resistance to insects through the use of insect control protein gene-WGA (Wheat Germ Agglutinin), a glycoprotein with molecular weight of 34000 Da. Toxic effect appears to be mediated through binding of the lectins (WGA) to glycoproteins in the insect leading to the disruption of gut epithelial cells and are believed to be “natures own insecticides”. The present study involves preparation of recombinant pGPTV vector having WGA gene, which was transferred to E. coli DH5α basic strain. The recombinant vector was transferred to Agrobacterium tumefaciens strain LBA4404 using helper strain through triparental mating. The recombinant vector having Agrobacterium was infected with tomato leaf discs through co-cultivation and the leaf discs were transferred to selection media containing Kanamycin and direct regeneration of the plantlet were obtained from the leaf discs. The npt-II gene (Kanamycin resistance gene) serves as a selectable marker system in plants. The regenerated plantlets grown on selection media was subjected to primary screening by isolating the genomic DNA by CTAB (Cetyl Trimethyl Ammonium Buffer) method and the transformation was confirmed by the presence of amplified fragments of WGA gene by PCR analysis
Antioxidant And Antibacterial Activity Of Methanolic Extract Of Machilus Odoratissima
Get PDFThe methanol extract of the bark of Machilus odoratissima was subjected to investigate its antioxidant and antibacterial properties. The phytochemical screening demonstrated the presence of different types of compound like terpenoids, tannins, deoxy sugar, saponins and phenolic compounds. The methanol extract of the plant was tested for antioxidant activity using scavenging activity of DPPH(1,1-diphenyl-2-picrylhydrazil) radical method and antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli & Pseudomonas aeruginosa bacteria using cup plate method. The extract exhibited high free radical scavenging activity. IC50 was found to be 3.37μg/ml. Antibacterial activity was observed against S. aureus in dose dependent manne
Fabrication Of Glimepiride Datura Stramonium Leaves Mucilage And Poly Vinyl Pyrrolidone Sustained Release Matrix Tablets: In Vitro Evaluation
Get PDFThe main purpose of the present work was to develop matrix tablets of Glimepiride with Datura stramonium leaves mucilage and Poly Vinyl Pyrrolidone and to study its functionality as a matrix forming agent for sustained release tablet formulations. Mucilage from Datura stramonium leaves was extracted, isolated, purified and characterized. Physicochemical properties of the dried powdered mucilage of Datura stramonium leaves were studied. Various formulations of Glimepiride Datura stramonium leave mucilage and Poly Vinyl Pyrrolidone were prepared. The formulated tablets were tested for mechanical properties, friability, swelling behavior, in vitro drug release pattern and the dissolution data was treated with mathematical modeling and the optimized formulation was tested for accelerated stability studies. The formulated tablets were found to have good mechanical properties, good swelling properties. The in vitro dissolution data was perfectly fitting to zero order and the release of drug from the formulation followed Higuchi’s release. The accelerated stability studies revealed that the tablets retain their characteristics even after stressed storage conditions. From this study it was concluded that the dried Datura stramonium leaves mucilage and Poly Vinyl Pyrrolidone combination can be used as a matrix forming material for making sustained release matrix tablets
Sediment Impact On Turbine Material: Case Study Of Modi River, Nepal
No full textHydropower is considered as one of the most economical and stable base energy source compared with other sources of energy of Nepal. Researches coherent to this field are not new but yet it is not sufficient, lots of tiles have to be kept for better understanding of hydropower effecting elements. Sand is the most affecting element that damages the turbine blades, so research on relation of sand and turbine is most. This research is done to find out the impact of sediment on turbine material. Modi River sediment at eight different stations has been taken as sample and its erosion rate in turbine blade sample specimen has been accounted in this study. Rotating disc apparatus has been utilized to find out the total impact of sand on turbine material. Four same kind of test turbine material is used on single rotating disc all at a time at same condition to define sand impact. Thirty gram (gm) of sediment mixed with three liters of water is used to strike sample pieces for five minutes. Two different tests of sediment samples of 8 different locations were studied. After all the test it is observed that the first test sand sample of location 1 and turbine material 1 has the highest impact with a weight loss of 7.764 mg and least impact in sand sample location 1 and sand sample 3 with a weight loss of 3.5 mg. Average weight loss of turbine material in first location is 5.929 mg which is the greatest impact and 4.0083 at eight locations which is the least. Relating to turbine material first rotating disc turbine specimen P0A has been affected highly with weight loss of 9.289 mg and less eroded on P5A rotating turbine specimen with weight loss of 1.2 mg
A Review On Bioremediation Of Petroleum Hydrocarbon Contaminants In Soil
Get PDFThis review article illustrates the pros and cons of using bioremediation process for the remediation of petroleum contaminants in soil. Bioremediation along with other processes have been used to remediate petroleum hydrocarbon contaminants in soil in past. The major constituents of most crude oils are biodegradable, so bioremediation has proven to be cheap and efficient than others techniques. Different organisms are employed using various technique of bioremediation according to hydrocarbon present in the contaminated soil. Bioremediation is simpler, less labor intensive and public attitude toward bioremediation are generally favorable, the lack of knowledge about microorganisms and their natural role in the environment could affect the acceptability of their use. However, bioremediation can be considered one of the best technologies to deal with petroleum product contaminated soil
Biotic Response To Acidification Of Lakes – A Review
Get PDFAcidification has far reaching environmental and ecological impacts. It brings change in the chemical, physical and biological composition of the environment and thereby affects the behavior and adaptation of the organisms in the changing environment. In this paper research articles published on acidification and its effect on the biota, with focus on high altitude lakes, are reviewed covering phytoplankton (diatoms), macrophytes, zooplankton, and benthic macro invertebrates. The areas considered in review highly affected by acidification are Scandinavia, Central Europe, Scotland, Canada, United States and Sweden. The specific causes of acidification, its problem and prospect in the high altitude Himalayan lakes with scope and the technique of the studies are also discussed
Ethnoveterinary Practices Of Some Plant Species By Ethnic People Of Parbat District, Nepal
Get PDFIn Parbat district, tribal communities rear livestock mostly cattle, buffalo, goats, sheep etc. Most of the time animal diseases are treated by the uses of local herbal medicines extracted from the plants. All together 21 plant species belonging to 19 families are being identified having used to treat different veterinary diseases like; injury, poisoning, foot and mouth, wounds, stomach disorder, antiworms and bone facture of animals. These ethnoveterinary plants species are normally collected from nearby forest or natural vegetation. Some of them like, Acorus calamus, Cuscuta reflexa, Schima wallichii, Fraxinus floribunda etc are even domesticated by them in nearby cropland therefore such plants are readily available at any time
Land Use Planning In Hydropower Development A Case Study Of Upper Tamakoshi Hydroelectric Project
Get PDFMany developing countries do not focus on land use planning in hydropower development. As a result hydropower projects are not sustainable. The aim of the study is to analyze the cause and effects of land use planning in hydropower development. The primary and secondary data were collected in a case study site at the Upper Tamakoshi Hydroelectric Project (UTHEP) in Dolakha district of Nepal. Household questionnaire, key informants? interviews and field observation were conducted to collect primary data while the relevant documents such as detailed feasibility report, property valuation report and spatial data (cadastral data, image etc.) were also collected for the study. The primary and secondary data reveals that Land use changes involved in the UTHEP implementation is basically due to the permanent and temporary land acquisition for project structures, facilities and reservoir area. The total land acquired for various project components like access road, powerhouse, desanding basin, reservoir as well as construction borrow pits and quarries, temporary and permanent work camps and construction of access road is estimated to be 182 ha. The secondary data reveals that 66 ha are allocated in agricultural land, 78 ha in forest land and 38 ha in the barren and cliff land. The results from secondary data and interviews confirm that UTHEP has planned to distribute 10% share to the residents of Dolakha district to promote local level investment. Finally, the study finds that land use planning has very important role for minimizing negative social and environmental effects thus create sustainability of the hydropower projects. It is also found that overall environmental impacts are limited because of technological development such as tunnel and underground powerhouse in UTHEP. The land tenure, Land use planning stakeholders and their role, Governance, policy, social structure etc. are the basic requirements of land use planning for sustainable development of hydropower projects
Bioactive Volatile Compounds Of Three Medicinal Plants From Nepal
Get PDFThe volatile organic compounds of Asparagus racemosus, Bergenia ciliate and Terminalia chebula were isolated by simultaneous distillation–extraction (SDE) technique and then analyzed by gas chromatography–mass spectrometry (GC-MS). A total of 55, 48 and 56 compounds were identified from and compounds camphor, borneol, capric acid, furfural, myrtanal, α-pinene, α-terpeniol, perillaldehyde, 2-carene, butyrophenones, furfural, β-caryophyllene, 2-nitropropane were detected as a bioactive compounds with various proportions among the studied plants
An Experimental Study On Flow Field Around Inundate Bell Mouth Groin
No full textA study was undertaken to investigate the flow field around bell mouth groin in a large mobile bed physical model facility (46m x 11 m). A total number of 24 test runs were conducted. Three different discharges and four different angles and two groin conditions (submerged and non-submerged) was considered. All tests were conducted for 8 hours duration in clear water condition. Velocity data have been collected forming grids in both vertical and horizontal direction around the vicinity of the bell mouth groin. Velocity was measured at 0.2, 0.4, 0.6 and 0.8 depths from the water surface by forming grids. Change in flow conditions around bell mouth groin for various test run have been analyzed non-dimensionally in longitudinal, lateral and vertical direction. The streamwise velocity along lateral direction was found that the lateral shifting of maximum velocity away from the head of the bell mouth groin. In most cases, streamwise vertical velocity in lower part of the channel is found higher than that of upper part. Streamwise vertical velocity profile has been found variable with different discharges and does not follow its natural logarithmic pattern. Velocity vector indicates that flow is steady at upstream along longitudinal direction. The flow diverted at head of structure and flows through sides of structure towards downstream. A circulation of flow has been observed around head of structure after diverting of flow towards down. Immediately after rear front of structure, relatively weak circulation of flow has been observed. In this paper the results of test runs conducted under submerged conditions for 1500 and 900 angles are reported