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ThesisItem Open Access A Study of the biosynthesis of phospholipids in pythium irregulare buisman(Punjab Agricultural University, Ludhiana, 1974) Krishan, Baldev; Bhatia, I. SThesisItem Restricted Comparative sutdy of the quality and synthesis of microbial protein in the Rumen of zenj Cattle & Buffalo when fed on differetn rations(Punjab Agricultural University, Ludhiana, 1968) Singh, Gajindar; Bhatia, I. SThesisItem 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 Value-added chemicals from lignin and hemicellulose fractions of sugarcane bagasse(Punjab Agricultural University, Ludhiana, 2016) Ramandeep Kaur; Uppal, S.K.Sugarcane bagasse was analyzed for its chemical composition and was found to contain cellulose, hemicellulose, lignin 42.11, 28.42, 19.20%, and glucan, xylan, arabinan, acid insoluble lignin, acid soluble lignin, ash 39.65, 21.46, 2.75, 15.10, 3.31, 3.96%, respectively. Maximum lignin extraction (17.60%) was found to be with 10% NaOH which was further confirmed by scanning electron microscopy images. Lignin was chemically modified by oxidation, acetylation, epoxidation and hydroxymethylation and characterized using FT-IR, 1H, 13CNMR spectra. HPLC analysis revealed p-coumaric acid as major phenolic acid in bagasse lignin (14.76 mg g-1 bagasse) followed by ferulic, vanillic and syringic acid. p-Coumaric and ferulic acid were isolated, derivatized into esters (reactions with alcohols) and amides (reactions with amines, amide linking reagent EDC-HCl (N-(3-dimethylaminopropyl)-N’-ethylcarbodiimide) and 1-hydroxybenzotriazole, HOBt) and characterized by FT-IR, 1H, 13CNMR spectra and elemental analyses. Lignin, modified lignins, phenolic acids and their derivatives were evaluated for antioxidant (DPPH radical scavenging) activity and antibacterial activity against Bacillus aryabhattai, Acinetobacter sp. and Klebsiella sp. Lignin and its oxidized and hydroxymethyl derivative were observed to have higher antioxidant activity than 3,5-di-tert-butyl-4-hydroxytoluene (BHT) and lower than 3-tert-butyl-4-hydroxyanisole (BHA). Phenolic compounds and their derivatives were effective at lower concentrations for antibacterial activity than lignin and modified lignins. Xylooligosaccharides (XOS) were produced from bagasse by xylan extraction (5, 10, 15% KOH and NaOH) followed by acid hydrolysis (0.25 and 0.50MH2SO4; 20, 40, 60min) and analyzed by HPTLC. The best treatment for xylan hydrolysis leading to increased production of XOS and reduced concentration of xylose was found to be 0.25MH2SO4 for 20 min. XOS were found to be better prebiotics for three probiotic bacteria viz. Lactobacillus acidophilus, Lactobacillus brevis and Lactobacillus viridescens than glucose and standard fructooligosaccharides.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 Chemistry of sesquiterpenoids from Inula racemosa and their evaluation as pesticides(Punjab Agricultural University, Ludhiana, 2017) Ramandeep Kaur; Chahal, K. K.The dissertation incorporates the isolation of sesquiterpene lactones- alantolactone and isoalantolactone from root extract of Inula racemosa using extensive column chromatography over silver nitrate impregnated silica gel. Reduction of these isolated compounds was carried out using sodium borohydride, lithium tri-tert-butoxyaluminohydride and magnesium in methanol. Dibromocyclopropane derivatives were prepared using bromoform/potassium hydroxide in presence of phase transfer catalyst. Allylic oxidation of isoalantolactone was carried out selenium dioxide and tert-butyl hydroperoxide. Decomposition of pyrazoline derivatives of sesquiterpene lactones under heat, microwave and ultraviolet radiations (in presence or absence of sensitizer) were carried out. I. racemosa root extract was partitioned into its non-polar and polar fractions and were subjected to various biological activities using different methods such as mortality, repellency and antifeedant assay for insecticidal activity against Tribolium castaneum; 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. Non-polar fraction was most effective in all bioassays except in egg hatch inhibition studies where root extract was most effective. Isolated compounds and their derivatives showed antifungal potential against three test fungi. Isoalantolactone derivatives were more effective in comparison to alantolactone. Based on antifungal activity structure activity relationship was derived.
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