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ThesisItem Restricted Synthesis of hybrid benzimidazoles-metal sulfide nanoformulations as antifungal agents(Punjab Agricultural University, Ludhiana, 2020) Radha Rani; AnjaliThree samples of MS-NSs viz. CuS-NSs, FeS-NSs and MnS-NSs were prepared using sonochemical mediated reaction. Co-precipitation method produced three samples of MSNRs viz. CuS-NRs, FeS-NRs and MnS-NRs in solid form. Statistical analysis of antifungal potential of MS-NPs against phytopathogenic fungi of rice viz. D. oryzae, F. verticillioides, C. lunata and S. oryzae indicated that CuS-NSs exhibited the best antifungal potential. A series of 32 compounds containing benzimidazole and 1,2,4-triazole, in a single molecule, were designed using variety of spacers between the two bioactive moieties. Only four compounds viz. 1, 4, 5 and 8 were chosen for synthesis following the combined criteria of stronger binding to tubulin and lanosterol 14 -demethylase (with docking score -5.9 and - 8.9Kcal/mol, respectively), Lipinski filtrations, FMO approach and Toxtree analysis. Compound 8 (4-(1H-benzo[d]imidazol-2-yl)-2-methoxyphenyl 2-(1H-1, 2, 4-triazol-1- ylamino) acetate) was found to be the best antifungal compound against all the test fungi (ED50 16 μg/ml). U-CuS-NSs underwent in situ surface modification, via organic coating with most active benzimidazolyl-1,2,4-triazole i.e compound 8 to produce their nanohybrid (NH-CuS-8). Comparison of ED50 values led to the conclusion that hybridization of CuS-NSs with compound 8 worked well in enhancing antifungal potential of CuS-NSs against all test fungi. Priming the seeds with solutions of FeS-NSs and MnS-NSs resulted in improved seed health but CuS-NSs had negative impact. Seed treatment evaluation studies revealed great potential of NH-CuS-8 to reduce fungal infection.ThesisItem Open Access Evaluation of synthesized ternary doped ferrite nanoparticles and their graphene oxide composites as enzyme mimics and photocatalysts(Punjab Agricultural University, Ludhiana, 2020) Vibha; Manpreet KaurRole of nanoferrites and their graphene Oxide (GO) composites as enzyme mimics and photocatalysts is a thrust area of research. In the present work, pure and ternary doped ferrite nanoparticles (NPs) of Mn, Co and Cu and their GO nanocomposites (NCs) were synthesized using facile sol-gel and sonication method respectively. FT-IR spectra and XRD patterns confirmed the formation of single phase ferrite NPs, GO sheets and their NC. Maximum saturation magnetization value was 65.0 emu/g for ternary ferrite NPs having formula Mn0.4Co0.4Cu0.2Fe2O4. SEM and TEM micrographs revealed the porous nature and fabrication of ferrite NPs onto GO sheets in the NCs. The larger surface area of NCs as compared to pristine NPs was confirmed by BET studies. Synthesized NPs, GO and NC were evaluated as peroxidase, superoxide dismutase (SOD) and polyphenol oxidase (PPO) enzyme mimics. MnFe2O4 NPs exhibited maximum peroxidase and PPO mimic activity, whereas SOD mumic activity was shown by CuFe2O4 NPs. Observed results were explained on the basis of structure of ferrite NPs. Synergistic adsorption and photocatalytic potential of ferrite NPs, GO and NC was studied using malachite green and methylene blue as model compounds. The adsorption data was best fitted into Langmuir adsorption isotherm and followed pseudosecond- order kinetic model. The NC exhibited better adsorption and photocatalytic activity as compared to ferrite NPs under visible light. The degradation mechanism was proposed on the basis of mass spectrometric analysis of products formed during photodegradation.ThesisItem Open Access Physico-chemical studies of natural and synthesized biocomposites for remediation of imidazolinone herbicides(Punjab Agricultural University, Ludhiana, 2019) Paawan Kaur; Pervinder KaurThe present investigation was undertaken to study the removal of imidazolinones herbicides from water and soil using natural and synthesized biocomposites. Under the optimum experimental conditions, chitosan-bentonite biocomposites and treated rice husk adsorbents were prepared, characterized and investigated for their potential to adsorb imazethapyr and imazamox from water using batch equilibrium techniques. The adsorption capacity of synthesized adsorbents (0.0067 x 103 to 13.279 x 103 μg1−ng−1mln) for herbicides was greater as compared to natural adsorbents (0.0026 x 103 to 0.0142 x 103 μg1−ng−1mln). Among the studied adsorbents, thermally treated rice husk was superior for the removal of imazethapyr and imazamox from water in terms of adsorption capacity (6.986 x 103 to 13.279 x 103 μg1−ng−1mln) and desorption (92.82 to 99.34 %). The removal of imazethapyr and imazamox from artificially contaminated soil was evaluated using -cyclodextrin-chitosan biocomposites through adsorption-desorption and pot trials viz. chemical assay and bioassay. The removal studies indicated greater efficiency of chitosan, -CD and their biocomposites to remove imazethapyr and imazamox from soils as compared to distilled water. Among the extractants, low molecular weight chitosan- -cyclodextrin biocomposite (LCD) had greater removal efficiency and under optimum conditions, 59.42 to 99.44 % of adsorbed herbicides were successfully desorbed from studied soils. Chemical assays indicated that amendment of LCD to soils enhanced the dissipation of imazethapyr and imazamox and the residues were below detectable limit (<0.005 μg g−1) within 5 to 21 days depending upon the physicochemical properties of soils. Bioassay studies indicated significant reduction in growth inhibition of Brassica juncea (L.) Czern after the amended of soils with LCD and corroborated the findings of chemical assay.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 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 Chemistry of sesquiterpenoids from essential oil of Cyperus scariosus and their antioxidant and antifungal potential(Punjab Agricultural University, Ludhiana, 2018) Amit Kumar; Chahal, K.K.The present investigation deals with Chemistry of sesquiterpenoids from essential oil of Cyperus scariosus and their antioxidant and antifungal potential. The roots of C. scariosus were grounded and subjected to hydro-distillation using Clevenger apparatus to extract the essential oil. The essential oil was analysed by gas chromatography-mass spectrometry. A total of 30 compounds, accounting for 93.30 % of the total essential oil, were identified. Longiverbenone, nootkatone, caryophyllene oxide and cyperene were found to be the major compounds present. The C. scariosus roots were also extracted by Soxhlet extractor using three different solvent i.e. hexane, dichloromethane and methanol. Total of 55, 67 and 25 compounds were present in hexane, dichloromethane and methanol extracts respectively. Cyperene, isolated from essential oil was chemically derivatized into cyperotundone, cyperene alcohol, cyperenol, cyperenal and cyperene epoxide. The structures of the compounds were elucidated on the basis of FTIR, 1H NMR and 13C NMR spectroscopy. C. scariosus essential oil, various extracts, isolated and derivatized compounds were tested for antifungal and antioxidant activities at different concentrations viz.0.05, 0.1, 0.25, 0.5 and 1.0 mg/mL respectively. All the extracts and essential oil showed significant antifungal activity. Essential oil was most active as compared to other tested components against all plant pathogens. The antioxidant activity of C. scariosus essential oil, various extracts, isolated and derivatized compounds was carried out in vitro using involving 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical scavenging potential, inhibition of nitric oxide radical generation and ferric reducing antioxidant power assay. Methanol extract of C. scariosus showed highest antioxidant activity in all the methods tested as compared to essential oil, hexane and dichloromethane extracts. Cyperenol showed highest antioxidant activity as compared to isolated and derivatized compounds.ThesisItem Restricted Isolation and characterization of terpenoids from vetiver oil and their evaluation as pesticides(Punjab Agricultural University, Ludhiana, 2016) Urvashi; Chahal, K. K.The dissertation incorporates the isolation of Khusinol along with two hitherto unknown cadinane sesquiterpenoids, Cadin-4(5)-ene-2β-ol and Cadin-10(14)-ene-13β-ol from vetiver oil using extensive column chromatography over silica gel/ modified silica gel. Epoxidation of Khusinol with perbenzoic acid, vanadium oxy acetyl acetonate/t-butyl hydroperoxide and N-bromosuccinimide/ sodium hydroxide revealed that epoxidation preferably occurred at exomethylenic double bond. Khusinol was also treated with mercuric acetate/ sodium borohydride, dry hydrochloric acid gas and iodine-benzene system to yield different products. Vetiver essential oil was partitioned into its non-polar and polar fractions. Vetiver oil and its fractions were subjected to various biological activities using different methods such as mortality, repellency and antifeedant assay for insecticidal activity against Sitophilus oryzae; egg hatch inhibition and juvenile mortality test for nematicidal activity against Meloidogyne incognita and spore germination inhibition for fungicidal activity against three fungi i.e. Alternaria triticina, Drechslera oryzae and Fusarium moniliforme. In all the bioefficacy studies, vetiver oil was found to be more effective as compared to its fractions and activity increased with increase in concentration. Among fractions, non-polar fraction was more effective for insecticidal activity whereas polar fraction for nematicidal and fungicidal activities. The results indicated that pesticidal action of vetiver oil was due to synergetic effect of non-polar and polar compounds present in vetiver oil. Khusinol was found to be most active antifungal agent as compared to all the isolated and derivatized compounds of Khusinol. Structure-activity relationship of isolated and derivatized compounds for antifungal activity was studied.ThesisItem Restricted Effect Of Anions,Ionic Strength,Ph Organic Matter And Temperature On Boron Adsorption By Soils(Punjab Agricultural University; Ludhiana, 2000) Arora, Harsh; Bhardwaj, S. S.