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ThesisItem Open Access Metal Complexes of Highly Functionalized Phenylpyrimidine and Phenylpyridine Derivatives: Synthesis, Characterization, Biological Screening and Computational Insights(G.B. Pant University of Agriculture and Technology, Pantnagar-263145, 2024-03-01) Thakuri, Shweta Chand; Viveka NandMulti-component reactions were carried out to synthesize phenylpyrimidine and phenylpyridine derivatives along with their metal complexes. The ligand and metal complexes were then characterized by various physio-analytical and spectral methods including Mass spectrometry, FTIR, UV-Vis spectroscopy, NMR, AAS and elemental analysis. The prepared ligand and metal complexes were then screened for their various biological activities like anti-oxidant, antii nflammatory, anti-diabetic, herbicidal and antibacterial activity. The anti-oxidant potential was assessed by DPPH free radical scavenging, H2O2 hydroxyl radical scavenging and FRAP (Ferric Reducing Antioxidant Potential) methods. In case of complexes of phenylpyrimidine and phenylpyridine derivatives, best % radical scavenging activity was shown by L1CFe (77.54±0.148) and L2CFe (78.733±0.048) respectively for DPPH free radical scavenging assay. For H2O2 hydroxyl radical scavenging activity assay, L1CCu (78.11±0.061 %) showed best % radical scavenging activity among the complexes of phenylpyrimidine derivatises while L2CZn (78.2±0.026 %) was the best among complexes of phenylpyridine derivatives. In case of FRAP assay, L1CZn (FRAP- 16.41±0.036) and L2AFe (FRAP- 13.83±0.026) showed best activity. The complexes were screened for their anti-inflammatory activity by Egg-Albumin methods. The best activity was shown by L1CFe (IC50- 553.47±2.790) and L2CFe (IC50- 525.19±18.327) among the complexes of phenylpyrimidine and phenylpyridine derivatives, respectively. The Anti-diabetic activity was performed by α-amylase inhibition method. For α-amylase inhibition activity, L1CCu (% inhibition- 84.75±0.082%), L1CZn ((% inhibition- 84.67±0.074%), L2CCu ((% inhibition- 80.32±0.082%) and L2CZn ((% inhibition- 79.58±0.074%) showed best activity. In case of herbicidal activities, phenylpyridine derivatives and their metal complexes showed better % root and % shoot inhibition activity than the phenylpyrimidine derivatives. Two Gram-positive (B. subtilis and S. aureus) and two Gram-negative (E. coli and E. amylovora) bacterial strain were used for anti-bacterial activity. Compounds showed high resistance towards B.subtilis. Among the two schemes, phenylpyrimidine derivatives were found to be more effective than phenylpyridine derivatives against the tested bacteria, while Cu (II)-metal complexes consistently performed better than other metal complexes. The compounds were also screened for ADMET and oral toxicity and they were found to be within the limits. L1C ligand outperformed all other ligands with LD50 of 6200 mg/Kg, belonging to toxicity class VI. Molecular docking study was conducted to understand the molecular mechanism of antibacterial activity of compounds where the prepared metal complexes showed good interaction, validating their antibacterial activity. On the basis of the above results, it can be concluded that complexes of phenylpyrimidine and phenylpyridine derivatives may be promising candidates as an antioxidants, anti-inflammatory, antidiabetic and antimicrobial agent with low toxicity and suitable drug-likeliness.ThesisItem Open Access Studies on Metal Complexes of Mannich and Salen- Type Schiff Bases: Synthesis, Characterization, Cheminformatics, and Biological Activities(G.B. Pant University of Agriculture and Technology, Pantnagar-263145, 2024-01-01) Panwar, Mohit; Kasana, VirendraMannich bases, Schiff bases and their metal complexes were synthesised in these multicomponent reactions. The ligand and metal complexes were then characterized by various physioanalytical and spectral methods including Mass spectrometry, FTIR, UV-Vis spectroscopy, NMR, elemental analysis and AAS methods. The prepared ligand and metal complexes were then screened for their various biological activities like anti-oxidant, anti-inflammatory, anti-diabetic, herbicidal and antibacterial activity. The anti-oxidant potential was evaluated by DPPH free radical scavenging, H2O2 hydroxyl radical scavenging and FRAP (Ferric Reducing Antioxidant Potential) methods. In case of Schiff base complexes, best activity was shown by SGC (IC50- 471.244±0.532) and C1B (IC50- 529.59±4.33) showed best activity in case of Mannich base complexes for DPPH free radical scavenging assay. For H2O2 hydroxyl radical scavenging activity assay, SHB (IC50- 548.149±19.982) showed best activity in case of Schiff base complexes and C3C (IC50- 478±12.190) in case of Mannich base complexes. In case of FRAP assay, SAD (FRAP- 13.828±0.032) and C3D (FRAP- 15.457±0.026) showed best activity. The complexes were screened for their antiinflammatory activity by Egg-Albumin methods. The best activity was shown by SAF (IC50- 484.144±8.224) and C2D (IC50- 494.166±0.843) for Schiff base and Mannich base complexes, respectively. The Anti-diabetic activity was performed by α-amylase inhibition method. For α- amylase inhibition activity, SAC (IC50- 503.335±5.180) and C3C (458.912±1.445) showed best activity. In case of herbicidal activities, Schiff base and their metal complexes showed better % root and % shoot inhibition activity than the Mannich bases. Two Gram-positive (B. subtilis and S. aureus) and two Gram-negative (E. coli and E. amylovora) bacterial strain were used for antibacterial activity. Compounds showed high resistance towards B. subtilis. Among the two schemes, Mannich bases were found to be more effective than Schiff bases against the tested bacteria, while Cu (II)-metal complexes consistently performed better than other metal complexes. The compounds were also screened for ADMET and oral toxicity and they were found to be within the limits. SH ligand outperformed all other ligands with LD50 of 14930 mg/Kg, belonging to toxicity class VI. Molecular docking study was conducted to understand the molecular mechanism of antibacterial activity of compounds where the prepared metal complexes showed good interaction, validating their antibacterial activity. On the basis of the above results, it can be concluded that Schiff base and Mannich bases metal complexes may be promising candidates as an antioxidants, anti-inflammatory, antidiabetic and antimicrobial agent with low toxicity and suitable drug-likeliness.ThesisItem Open Access Response of Sweet Sorghum to Subsoiling and Nitrogen Management in Mollisols of Himalayan Foothills(G.B. Pant University of Agriculture and Technology, Pantnagar-263145, 2024-03-01) Manoj Kumar; Pal, Mahendra SinghA field experiment was conducted during the Kharif season of 2011 and 2012 at Instructional Dairy Farm, Nagla, G.B. Pant University of Agriculture and Technology, Pantnagar, U. S. Nagar (Uttarakhand). The soil of experimental field was well drained and slightly silty clay loam in texture with pH 7.21. The available organic carbon was 0.72% and available nitrogen, phosphorus and potassium were 272.3, 29.0 and 236.1 kg/ha, respectively. The experiment consisted of four tillage options in main plot i.e. conventional tillage (CT), subsoiling (20 cm) fb rotavator x1 (SS fb R), subsoiling-cum-deep placement (40 cm) fb rotavator x1(DP fb R) and subsoiling-cum-differential rate placement of fertilizers (25 & 50 cm) fb rotavator x1(DRF fb R) and four nitrogen levels in sub plot i.e. control (zero nitrogen), 40, 80 and 120 kg/ha were laid out in split plot design with four replications. Sweet sorghum variety SPSSV-6 was sown on 07 June 2011 and 12 May 2012. Tillage and nitrogen levels had significant effect on growth, yield and quality parameters of sweet sorghum during both the years. In general, DRF fb R and 120 kg N/ha gave the highest values of growth, yield and quality parameters. DRF fb R produced 3.8, 11.2 and 23.7 % higher stalk yield as well as 6.3, 13.5 and 23.8% green fodder yield than DP fb R, SS fb R and CT, respectively. Similarly, DRF fb R gave on an average 22.2, 28.7 and 30.1% higher juice yield; 34.7, 45.3 and 47.6% higher sugar yield and 23.2, 41.7 and 45.1% higher ethanol yield than DP fb R, SS fb R and CT, respectively. The crude protein and HCN content was also recorded higher under DRF fb R but was non-significant with DP fb R, SS fb R and CT. Application of 120 kg N/ha resulted into 9.3, 20.3 and 28.3% higher green fodder yield, 13.2, 27.6 and 37.9% juice yield, 27.6, 59.0 and 76.3% sugar yield as well as 29.3, 57.8 and 62.8% ethanol yield than 80, 40 and control (0) kg/ha, respectively. The crude protein yield and HCN content were recorded significantly highest at 120 kg N/ha. The bulk density was recorded significantly lowest under DRF fb R, while it conserved significantly highest soil moisture but nitrogen levels didn’t affect both bulk density and soil moisture. Hence, it is concluded that sweet sorghum may be planted under differential rate placement of fertilizers P and K at 25 and 50 cm depth (DRF fb R) with application of 120 kg N/ha for higher growth, stalk, fodder, juice, sugar and ethanol production in Mollisols of Uttarakhand.ThesisItem Open Access Study on Oxidative Stress in Subclinical Mastitis and Therapeutic Evaluation using Various Antioxidants in Buffaloes(G.B. Pant University of Agriculture and Technology, Pantnagar-263145, 2023-06-01) Johri, Aprajita; Arora, NiddhiThe present investigation was undertaken to determine the prevalence of subclinical mastitis in buffaloes followed by bacterial isolation and determination of various oxidative stress parameters alongwith comparative therapeutic evaluation using various antioxidants in different treatment regimen. The overall prevalence of subclinical mastitis in buffaloes recorded in and around Pantnagar was 19.00%.The highest prevalence was recorded in crossbred graded murrah buffalo breed in their early lactation stage with more predispositions towards hind quarters. Staphylococcus aureus followed by other streptococci and coagulase negative staphylococci were found to be major causative agents of bubaline mastitis. The overall antibiogram of major bacterial isolates showed the highest sensitivity to Enrofloxacin. There was significant rise in the levels of LPO,TNO,NO2-,NO3- while significant fall in the levels of serum ascorbic acid, TAC,FRAP and SOD in buffaloes with SCM. These outcomes were suggestive of oxidative stress persistence in the udder. To combat oxidative stress induced subclinical mastitis, various antioxidants like ascorbic acid (vitamin C) in the form of P. emblica supplememtation, vitamin E and selenium were given for 15 days in different therapeutic regimen. Therapeutic trial revealed highest efficacy in response to treatment with standard antibiotic therapy based on culture and sensitivity followed by combined supplementation of ascorbic acid (vitamin C) in the form of P. emblica, vitamin E and selenium. Whereas, the lowest efficacy was observed in response to vitamin E and selenium administration. In conclusion, it can be said that antibiotic therapy based on culture and sensitivity is the mainstay treatment of bubaline mastitis and combination of antioxidants can be used in the treatment protocol as an adjunct to antibiotic therapy to improve the severity of infection and minimizing oxidative stress. The natural sources of various antioxidants give more fruitful results in comparison to commercially available antioxidants as they are economic,easily accessible and do not leave any antibiotic residue in milk.ThesisItem Open Access Performance Analysis of Line Start Permanent Magnet Synchronous Motor using Finite Element Method(G.B. Pant University of Agriculture and Technology, Pantnagar-263145, 2022-10-01) Dwivedi, Harsh; Rawat, H. S.The transportation sector accounts for 23% of greenhouse gas (GHG) emissions worldwide through vehicle fuel combustion. Meeting climate mitigation goals requires transformative changes in the transport sector. This includes transition from current fuel combusting vehicles to Electric Vehicles (EVs). EVs have the potential to have significant effects on energy, the environment, and transportation. Qualities like higher power density, smaller size and higher efficiency make PMSM a superior candidate than its counterparts. Therefore, the performance of Permanent Magnet Synchronous Motor (PMSM) is analysed in this thesis using Finite Element Method. A buried magnet type Line Start PMSM motor is simulated using Ansys Maxwell Software. Finite Element Method for the transient analysis of simulated PMSM in Ansys Maxwell software gave us better understanding of flux pattern and magnetic field. Concept of Cogging Torque is also discussed. A 3-phase Sinusoidal Pulse Width Modulated (SPWM) Inverter is simulated in Ansys Simplorer Software and Dynamic Analysis of above simulated motor is examined. Speed control techniques are discussed and Field Oriented Control (FOC) is implemented using MATLAB Simulink Software. Performance analysis of PMSM’s speed, torque and current for sudden load changes is observed. The FOC speed controller is than tuned for low maximum peak overshoot and low settling time using hit and trial method to give better results. PMSMs are becoming more and more relevance with the advent of power electronics devices, use of stronger magnets, and better speed control techniques.ThesisItem Open Access Performance Analysis of Line Start Permanent Magnet Synchronous Motor using Finite Element Method(G.B. Pant University of Agriculture and Technology, Pantnagar-263145, 2022-10-01) Dwivedi, Harsh; Rawat, H. S.The transportation sector accounts for 23% of greenhouse gas (GHG) emissions worldwide through vehicle fuel combustion. Meeting climate mitigation goals requires transformative changes in the transport sector. This includes transition from current fuel combusting vehicles to Electric Vehicles (EVs). EVs have the potential to have significant effects on energy, the environment, and transportation. Qualities like higher power density, smaller size and higher efficiency make PMSM a superior candidate than its counterparts. Therefore, the performance of Permanent Magnet Synchronous Motor (PMSM) is analysed in this thesis using Finite Element Method. A buried magnet type Line Start PMSM motor is simulated using Ansys Maxwell Software. Finite Element Method for the transient analysis of simulated PMSM in Ansys Maxwell software gave us better understanding of flux pattern and magnetic field. Concept of Cogging Torque is also discussed. A 3-phase Sinusoidal Pulse Width Modulated (SPWM) Inverter is simulated in Ansys Simplorer Software and Dynamic Analysis of above simulated motor is examined. Speed control techniques are discussed and Field Oriented Control (FOC) is implemented using MATLAB Simulink Software. Performance analysis of PMSM’s speed, torque and current for sudden load changes is observed. The FOC speed controller is than tuned for low maximum peak overshoot and low settling time using hit and trial method to give better results. PMSMs are becoming more and more relevance with the advent of power electronics devices, use of stronger magnets, and better speed control techniques.ThesisItem Open Access Parametrization of the Priestley-Taylor Model and its Comparison with Artificial Intelligence, Machine Learning and Statistical Models for Evapotranspiration Estimation over Sugarcane and Chickpea Crops(G. B. Pant University of Agriculture and Technology, Pantnagar- 263145, 2023-09-01) Satpathi, Anurag; Nain, A. S.The amount of crop ET depends on several factors such as land cover type, amount and duration of solar radiation, air temperature, speed of the wind above it etc. About 90% of the total water used in agriculture is lost either by evaporation from soil or crop transpiration. The actual crop evapotranspiration is an indicator of the water demand, crop stress, irrigation scheduling, drought and water budget study. The modified Priestley-Taylor model also called as surface temperature-vegetation index (Ts-VI) triangle method is used for estimating crop evapotranspiration over the Udham Singh Nagar district of Uttarakhand. Ground stations of LAS (Sugarcane), lysimeter (Chickpea) and EEFlux (METRIC) products were used for the validation of the MPT model results. Apart from this, statistical and Machine learning methods are also used for precise estimation of ET. Three sets of meteorological datasets were used for model development: first, Rn only as an input variable because Rn was found to be the variable with the highest correlation coefficient. Second, except Rn all other variables were taken as input variables and third all the variables including Rn were used to develop the models. The outcomes of this study will help to improve water management practices and increase crop yield in the region. The parameterized MPT model gives acceptable ET estimates compared to LAS (Sugarcane) and lysimetric (Chickpea) data for both rabi seasons of 2021-22 and 2022-23. The validation of the model by lysimetric data over chickpea crop during rabi season of 2022-23 (R2 = 0.71) shows similar agreement to the LAS data over sugarcane crop during rabi season of 2021-22 (R2 = 0.71) and 2022-23. The results show the reliability and usability of MPT model for ET estimation of various rabi crops over Udham Singh Nagar district. The comparison of results with the METRIC model products, available online at EEFlux portal show good agreement (R2 = 0.65 and 0.63) over Udham Singh Nagar district. In the machine and statistical models, there is a small difference between the performances of the first (Rn only) and third (all weather variables) scenarios in all models. In first and second scenario with limited weather variable data, the RF model performs best. The rankings can be given as: RF > ANN > SVR = KNN > ELNET = LASSO = Ridge = MLR. Slight Improvement in model performances were noticed in statistical and machine learning while taking all variables as input over only Rn as an input. The rankings of models can be given as: ANN > RF > ELNET = LASSO = MLR > KNN > Ridge > SVR. The best model performances of the MPT model were compared with the best ML model performances of each scenario. Machine learning methods easily outperform the MPT models. However, it is acceptable that MPT model results are not par compared with the machine learning models due to the fact that machine learning models are giving the value of PET while MPT model gives crop ET and machine learning model results were valid for the point observation, while MPT model is parameterized for the whole Udham Singh Nagar district.ThesisItem Open Access Computational Investigations on Induced Drag Reduction using Retrofitted Winglets(G. B. Pant University of Agriculture and Technology, Pantnagar- 263145, 2024-02-01) Chandra, Deepankar; Misra, AnadiOngoing advancements in aircraft wing design aims to enhance wing efficiency, particularly by optimizing wing shape to minimize the drag. One of the major contributors of the overall drag on the aircraft is Induced-Drag which is an outcome of the wingtip vortices. This study investigates the impact of incorporation of winglets to the wings of a Twin-engine Turboprop transport aircraft (ATR 72-500 selected for this study) during different phases of flight like take-off, cruise and landing. The primary function of winglets is to reduce the vortex at the wingtips, resulting in reduced induced drag and an enhanced aerodynamic performance. Using XFLR5 software, the selected aircraft wing was modelled with varying cant angles (0°, 30°, 60°, and 90°) and investigated using 3D panel method which is more accurate and efficient in comparison to methods like Lifting Line Theory and Vortex Lattice Method. The computational test results achieved through 3D Panel Method revealed that the wing modification with winglets is most effective at a cant angle of 60°, achieving the optimum reduced induced drag at wingtips. The optimal CDi value is observed at a cant angle of 60o, reaching – 0.00107. The negative sign depicts the reverse effect of induced drag i.e., supporting forward thrust.ThesisItem Open Access Process Optimization of Ultrasound Assisted Betalain Extraction from Celosia Cristata L. Flowers and its Application as a Natural Food Colourant(G. B. Pant University of Agriculture and Technology, Pantnagar- 263145, 2024-01-01) Bahar, Qayoom Sidique; Shahi, N. C.Colour plays a crucial role in food quality and marketability. As synthetic dyes raise increasing environmental and health concerns, there is a discernible shift towards the adoption of natural colors. Anthocyanins and betalains are derived from sources like grapes and red beets, are popular alternatives. Celosia cristata flowers, traditionally used in Kashmiri cuisine, offer betalains without the earthy flavor that is present in Beets. Non-conventional methods like ultrasound-assisted extraction can enhance efficiency for betalain extraction, making them ideal natural food colorants. The study aimed at optimizing ultrasound-assisted extraction parameters for betalains from Celosia cristata flowers, characterizing the extracts, and assessing their application in food as a natural colorant. The study investigated the betalain extraction from Celosia cristata, revealing a betalain content range of 5.03–9.19 mg/g dw. Ultrasound-assisted extraction produced the maximum betalain content of 9.19 mg/g dw, while a minimum of 24.36 mg/g dw of betalain content. Significance (1% level) of linear and quadratic terms for power, time, and liquid-solid ratio was observed. Total phenolic content ranged from 7.67 to 21.25 mg Gallic acid/g dw. Total flavonoid content varied from 4.30 to 12.21 mg Quercetin/g dw. Antioxidant activity ranged from 5.60% to 15.87%. These findings underscore the influence of extraction parameters on betalain, phenolic, flavonoid content, and antioxidant activity, providing crucial insights for potential food applications. Optimization with Response Surface Methodology yielded process parameters (Power 223 W, Time 18.44 min, L/S Ratio 33.80 ml/g dw), validated accurately with low percentage error. The FTIR spectra of the optimized aqueous extract revealed significant peaks, confirming the presence of betalain pigments. Thermal stability analysis via DSC indicated the degradation of extract onset at 94.2 ºC. This makes it suitable for enriching pasteurized flavored milk processed around 70-90 ºC. Stability tests at various temperatures over durations demonstrated the half-life of 62 days at 4ºC. LC-MS/MS identified betalains, including Celosianin I, Celosianin II, Dopamine Betaxanthin, 3Methoxytryamminebetaxanthin, and (S)-Trypotphan-betaxanthin in Celosia cristata extract. The study assessed flavored milk with varying Celosia cristata extract amounts. Treatment T2 (5 ml per 500 ml) achieved the highest color score, indicating a positive correlation between extract quantity and color improvement. The inclusion of Celosia cristata extract notably enhanced aroma scores without adversely affecting flavor, aroma, or aftertaste in various concentrations. Overall acceptability scores significantly rose with increased extract, highlighting its positive impact. Statistical analysis of color intensity using RGB values showed no significant change, likely due to low storage temperature. Similar results were observed in flavored yogurt.
