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ThesisItem Open Access Chemical derivatization and biological evaluation of major constituent of ajwain (Trachyspermum ammi L.)(Punjab Agricultural University, Ludhiana, 2018) Gaba, Jyoti; Sharma, SunitaAjwain is a herbal plant with important medicinal properties. In the present study, chemical composition of essential oil of two types of ajwain seeds (small and bold) has been determined with GC-MS analysis. Thymol (72.03, 71.80%) was found to be the major constituent followed by γ-terpinene (13.53%) and p-cymene (14.16%) in small and bold seeds respectively. Proximate composition studies estimated percentage of nutrients viz. protein (15.01, 12.81), total minerals (12.28, 6.26), moisture (30.90, 6.67), fat (6.10, 13.05), fibre (21.50, 25.30) and carbohydrates (31.21, 35.91) in small and bold seeds respectively. Specific mineral composition analysis showed phosphorus (0.13, 0.126) and potassium (1.03, 1.09) in per cent whereas Fe (560, 221), Zn (59.60, 56.40), Cu (2.30, 3.80) and Mn (76.80, 61.30) were detected in ppm. Various phytochemicals viz alkaloids, saponins, steroids, tannins, coumarins, flavonoids, phytosterols, phenols, chalcones and glycosides were present in different solvent extracts in both types of ajwain. Out of thymol and ajwain oil, former was found to be more effective antioxidant at all the tested concentrations. Different derivatives of thymol viz. formylated thymol (II), chalcone (III), pyrazoline derivatives (IV-VIII), dihydropyrimidinone (IX), mannich bases (X-XII), azo derivatives (XIII-XVIII), imine derivatives (XIX-XXI), thymol hydrazide (XXII), oxadiazole derivative (XXIII), triazole derivative (XXIV), hydrazones (XXV-XXVII), β-lactam derivatives (XXVIII-XXX) were synthesized. All synthesized compounds were characterized by their IR, 1H NMR and 13C NMR spectra. Ajwain essential oil, thymol and its derivatives were screened for antifungal activity against fungi viz. Fusarium moniliforme, Rhizoctonia solani, Dreschlera maydis and insecticidal activity against stored grain pest of chickpea Callosobruchus chinensis. Compounds II, XX and XXI were found to be the most effective compounds against all three tested fungi and insect. None of the synthesized compounds exhibited better antifungal activity as compared to standards.ThesisItem Open Access Adsorption and desorption characteristics of imazamox in soils of Punjab(Punjab Agricultural University, Ludhiana, 2018) Saini, Amita; Pervinder KaurThe adsorption-desorption behaviour of imazamox in three Punjab soils was evaluated using the batch equilibrium technique. The adsorption- desorption kinetics of imazamox were found to be a two step processand was well described by pseudo second order kinetic model. On the basis of the measured R2 values, the adsorption data fitted well in Freundlich model (R2> 0.998) followed by Langmuir (R2>0.981) followed by Temkin (R2>0.870) and D-R (R2>0.447). KFads ranged from 1.358 to 2.148 μg1−1/n g−1ml1/n indicating that imazamox has weak adsorption capacity that varied significantly with the concentration, temperature and properties of soil. KFdes was found to be higher as compared to KFads for the studied soils. Desorption of imazamox was hysteretic in all the studied soils and hysteresis coefficient varied from 0.001 to 0.015. Thermodynamic analysis showed that imazamox adsorption onto soils was a feasible, spontaneous and exothermic process which becomes more favourable at low temperature.ThesisItem Open Access Isolation, chemical derivatizations and biological activities of sesquiterpenolides from chicory and costus roots(Punjab Agricultural University, Ludhiana, 2018) Ravinder Singh; Chahal, K.K.The dissertation incorporates the Isolation, chemical derivatizations and biological activities of sesquiterpenolides from chicory and costus roots. The roots of chicory/costus were room dried and extracted by Soxhlet extractor using sequential extraction method with hexane, dichloromethane and methanol as the solvents. GC-MS analysis showed the presence of 22 and 35 compounds in chicory and costus hexane extracts. Isoalantolactone, dehydrocostus lactone and alantolactone were isolated as pure compounds from root extracts via extensive column chromatography over silica gel. Reduction of these isolated compounds was carried out using sodium borohydride. Allylic oxidation of isoalantolactone and dehydrocostus lactone was carried out selenium dioxide-TBHP and selenium dioxide impregnated silica gel-TBHP. Decomposition of pyrazoline derivatives of sesquiterpene lactones under heat, microwave and thermo-sonication were carried out. Chicory/costus root extracts, isolated and derivatized compounds were tested for in vitro antioxidant and antifungal activities against three rice pathogens at different concentrations. The antioxidant potential was evaluated using five different methods viz. DPPH, Hydroxyl, Nitric oxide, superoxide radical scavenging and FRAP assay methods. All the extracts showed promising antioxidant and antifungal activity. Methanol extract of chicory was most active amongst all tested extracts whereas dihydroxy dehydrocostus lactone was the most active sesquiterpenolide amongst tested compounds. Antifungal activity of hexane extract was better than all tested extracts. Isoalantolacone was most effective sesquiterpenoid out of all isolated and derivatized compounds. Field evaluation of bioactive extract revealed that chicory and costus roots hexane extracts were highly effective in controlling disease under field conditions.ThesisItem Open Access Physico-chemical studies on synthesized graphene oxidemagnesium ferrite based nanocomposites and their adsorption potential for Ni (II) ion(Punjab Agricultural University, Ludhiana, 2018) Navneet Kaur; Manpreet KaurRole of magnetic nanocomposites for the remediation of waste-water is a thrust area of research. In the present study, hybrid graphene oxide (GO) based inverse spinel magnesium ferrite (MgFe2O4) nanocomposites (NCs) with bentonite/charcoal/chitosan were synthesized using facile sonication method. p-XRD patterns confirmed the presence of spinel ferrite phase in the NCs with the crystalline size 8-32 nm. FT-IR spectra displayed absorption bands corresponding to GO, MgFe2O4 NPs and bentonite/charcoal/chitosan in the NCs along with red shift of bands corresponding to C=O, C=C and O-H stretching. TGA confirmed higher stability of NCs over pristine GO. MgFe2O4 NPs imparted appreciable saturation magnetization to the NCs (4.03-11.10 emug-1). SEM and TEM revealed high porosity and immobilization of clusters of MgFe2O4 NPs onto GO sheets in the NCs. BET surface area of the NCs ranged from 58.34 to 165.29 m2g-1 and was markedly higher than pristine MgFe2O4 NPs. Removal of Ni (II) ions was studied by batch adsorption method. Langmuir, Temkin and Freundlich models were followed in perfect way. Maximum adsorption capacity from Langmuir model ranged between71.43-111.11 mgg-1 for NCs. Kinetic data fitted pseudo-second-order equation. Thermodynamic parameters revealed spontaneous and endothermic removal using NCs; whereas using GO the removal was exothermic. Percentage removal of Ni (II) was maximum for MgFe2O4 NPs and their binary NCs with GO. Effect of co-existing ions on Ni (II) adsorption was studied in Pb-Cd-Ni-Zn system. NCs possessed higher removal potential for Pb (II) as compared to Ni (II) due to the lower hydration energy of the former. For electroplating waste-water the optimum adsorbent dose required for complete metal ion removal was higher than that for spiked water because of presence of other interfering ions.ThesisItem Open Access Synthesis and characterization of zinc sulfide (zns) nano aqua-emulsions for their antifungal evaluation against phytopathogenic fungi(Punjab Agricultural University, Ludhiana, 2018) Navdeep Kaur; AnjaliZinc sulfide nanoparticles in aqua-dispersed form were prepared by reaction of zinc acetate with sodium sulfide by sonochemical method. Zinc ion and sulfide ion coated ZnS nanoparticles were prepared in different molar ratios of ion to ZnS nanoparticles. The products were characterized by Transmission Electron Microscopy (TEM), UV-Visible spectroscopy (UV-Vis), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). All the synthesized samples of zinc sulfide nanoparticles were screened for their in vitro antifungal potential against various phytopathogenic fungi viz. C. capsici, P. drechsleri, P. cubensisand P. parasiticaby applying spore germination inhibition technique, using Copper Oxychloride and Metalaxyl-M + Mancozebas a standard for comparison of the results. The prepared samples exhibited excellent broad spectrum inhibitory activity against all the test fungi, at concentration as low as 5μg/ml, which was multifold lower than the standards used. ZnS:Zn+2(1:5) exhibited better results among all samples.ThesisItem Open Access Chemistry and antimycotic potential of mentha based shellac coatings against penicillium digitatum of kinnow fruit(Punjab Agricultural University, Ludhiana, 2018) Harpreet Kaur; Tandon, RituThe present study deals with chemistry and antimycotic potential of Mentha based shellac coatings against Penicillium digitatum of kinnow fruit. Essential oil (EO) of two species of Mentha viz. Mentha piperita and Mentha arvensis was extracted using Clevenger-type apparatus. Per cent yield of essential oil of M. arvensis (2.8%) was found higher than M. piperita (2.1%) Compositional analysis of M. piperita essential oil by GC-MS revealed presence of 51 compounds. M. piperita EO exhibited better antimycotic potential than M. arvensis EO against P. digitatum. Hence, Process of nanoemulsion (NE) development of M. piperita EO was optimized for parameters such as oil and surfactant ratio (v/v) with three sonication times (ST) with the help of probe ultrasonicator. Effect of surfactant concentration and sonication time on droplet diameter and electrical conductivity was studied. Nanoemulsion of 1:0.5 ratio of oil and surfactant with 20 min ST exhibited smallest droplet diameter as well as maximum stability at refrigerator temperature (4°C) than ambient temperature (25°C) over the storage period of 2 months. M. piperita based shellac nanoemulsions were prepared for the best.1:0.5 (v/v) oil and surfactant ratio. NE with 15 minute ST showed more effective inhibition (96.0%) against P. digitatum in comparison to other nanoemulsions as well as pure M. piperita EO (71.0%). Optical and SEM results showed morphological changes in treated fungus. Nanoshellac coating showed maximum inhibition at par with the standard Carbendazim.ThesisItem Open Access Structural and magnetic properties of ferric oxide-silica core-shell nanocomposite and its application for removal of cd (ii) ion(2018) Jaskirat Kaur; Manpreet KaurStructural and magnetic properties of ferric oxide-silica core-shell nanocomposites were investigated for facile removal of Cd(II) ions from water. Silica (SiO2), ferric oxide (Fe2O3) nanoparticles, Fe2O3@SiO2 and SiO2@Fe2O3 coreshell nanocomposites were synthesized by modified Stober’s method, co-precipitation method, surfactant assisted sonication method and surfacant assisted direct precipitation of SiO2 on the surface of Fe2O3 NPs respectively. Techniques viz. X-ray diffractiion pattern (XRD), Vibrating sample magnetometer (VSM), Brunauer-Emmett-Teller (BET), Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), and FT-IR spectroscopy were invastigated. The effect of different reaction parameters including adsorbent dose, temperature, contact time, pH, initial metal ion concentration of Cd(II) was studied. Optimum pH for adsorption was 6. With the increase of temperature, the removal efficiency of synthesized adsorbents for Cd(II) ions increased up to 55ºC and then decreased. Values of ΔGo found to be negative for all the adsorbents, indicating spontaneous nature of adsorption process. While, positive values of ΔH and ΔS for all adsorbents indicated the endothermic nature of adsorption process. The trend for the percentage removal of Cd(II) in the descending order was Fe2O3@SiO2 > Fe2O3 > SiO2@Fe2O3 > SiO2. The trend for the fitting of adsorption isotherms in descending order was Freundlich > Langmuir > Tempkin > D-R isotherms. The adsorption followed pseudo second order kinetics. The advantage of nanocomposites is enhancement of adsorption potential due to presence of Fe2O3 along with SiO2. The results signified that core-shell reversal is effective way of tailoring the properties of nanocomposites.ThesisItem Open Access Synthesis of nicotinic acid derivatives and their evaluation against root knot nematode(Punjab Agricultural University, Ludhiana, 2018) Jain, Nisha; Utreja, DivyaSeven amide derivatives of nicotinic acid were synthesized by condensation reaction of nicotinic acid adsorbed on silica gel with different aromatic amines. The characterization of synthesized derivatives was done using 1H NMR, 13C NMR and IR spectroscopy. The resulted compounds were also screened for their nematicidal activity against root knot nematode Meloidogyne incognita by egg hatching and mortality test. All the compounds exhibited significant nematicidal potential as compared to control. Maximum egg hatching inhibition potential was exhibited by N-(4-bromophenyl)nicotinamide while N-(2,4,5-trichlorophenyl)nicotinamide showed maximum mortality potential.ThesisItem Open Access Synthesis of novel 1,2,4-triazolosulfonamides as antifungal agents against phytopathogenic fungi(Punjab Agricultural University, Ludhiana, 2018) Lovepreet Kaur; AnajliA series of 1,2,4-triazolosulfonamides was synthesized by microwave irradiation method in excellent yield, using sulfonyl chlorides and 1,2,4-triazoles as starting materials. The products were characterized by FT-IR, 1H NMR, 13C NMR and screened for their antifungal potential against various phytopathogenic fungi viz. Alternaria alternata, Curvularia lunata, and Helminthosporium oryzae by poisoned food technique in terms of ED50 values. The synthesized compounds displayed moderate to significant activity. Among all test compounds, 4-Methyl-N-(1H-1,2,4-triazol-3-yl)benzenesulfonamide (4) and 4-Methyl-N-(4H- 1,2,4-triazol-4-yl)benzenesulfonamide (7) showed best antifungal activity against all test fungi with respective ED50 values 4.0 and 3.4 μg ml-1 against Alternaria alternata, 2.3 and 2.0 μg/ml against Curvularia lunata and 3.5 and 3.0 μg/ml against Helminthosporium oryzae, multifold lower than the standard fungicides used, Tilt and Captan. The results were rationalized on the basis of in silico analysis viz. Toxicity analysis, Docking analysis and Lipinski parameters.