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ThesisItem Open Access Seasonal chemical diversity of Acorus calamus L. accessions from different altitudes of Uttarakhand Himalayas: Pharmacological screening and analysis of genetic variability(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Archana; Om PrakashIn present study the elemental analysis, preliminary phytochemical screening, seasonal and altitudinal chemical composition of essential oils by GC-MS, isolation of compounds by column chromatography, biological activities like antioxidant assay and pharmacological potential of rhizome essential oils/major components (α and β asarone) from A calamus and genetic variability among three accessions were evaluated. The yields of essential oils in different seasons varied from 0.11 to 6.8 % w/v. The elemental analysis studied with the help of atomic absorption spectrometry (AAS), exhibited the presence of N, P, K, Ca, Mg, Ca, Mn, Fe, Cu, Cr, Pb, Ni, Zn. The presence of various secondary metabolites like carbohydrates, proteins, glycosides, flavonoids etc. were observed in all the accessions. GC-MS analysis essential oils, methanolic extracts of leaves and rhizomes of Acorus calamus exhibited various phenylpropanoids, monoterpenoids and sesquiterpenoids. The major compounds identified were trans methyl isoeugenol, Z isoelimicin, α asarone, β asarone and shyobunone. The isolation of the compound from rhizome methanolic extract by column chromatography and characterized by mass spectrometry and NMR proofs the presence of β asarone. The antioxidant activity of essential oils and methanolic extracts showed good to moderate antioxidant potential. The total phenols, flavonols and orthodihydric phenols in all the extracts were ranged from 11.11 to 133.33. 31.70mg/g gallic acid equivalent, 72.64mg/g catechin equivalent and 67.87mg/g respectively. The combination of isomers α+β-asarone at higher dose level of 100 mg/kg b.wt. exhibited significant antipyretic activity (75.10%), analgesic activity(48.87%) and anti-inflammatory activity (26.16%) compared to the standard drugs paracetamol (65.14%), ibuprofen (48.39%) and aspirin (20.98%) respectively. The essential oils and α, β asarones individually also exhibited good pharmacological activities with minimum at lower dose (50mg/kg b.wt.) and maximum at higher dose (100mg/kg b.wt.). The oils and isomers α and β asarones individually and in combination exhibited significant hepatoprotective activity in a dose dependent manner against CCl4 induced hepatotoxicity using silymarin as standard drug. The pharmacological activities associated with the combination of α and β asarones might be because of synergetic effect. The hepatoprotective activity of essential oils and pure compounds was supported by histopathological examination of livers in which a significant amount of regeneration in the liver was observed. No harmful toxic effects on rats were seen from rhizome The essential oil and major components did not show toxic behaviour. The genetic diversity by Simple sequence repeat (SSR) revealed monomorphic behavior of the species.ThesisItem Open Access Chemoprofiling, genetic profiling, biochemical, pharmacological screening of different ginger accessions and ginger extract bioconjugates and their application in nanoparticles synthesis(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Dhanik, Jyotsana; Viveka NandThesisItem Open Access Synthesis of novel polymer nanocomposites for electrochemical energy storage(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Joshi, Ila; Zaidi, M.G.H.A series of polymer nanocomposites (PNCs) was synthesized from Polyindole (PIN) and metal organic framework (MOF). For this purpose, C60 and WC were used as fillers. PIN based PNCs were synthesized through ferric chloride initiated chemical oxidative polymerization of Indole in presence of fillers (5-25, wt %) in supercritical carbon dioxide. MOF based PNCs were synthesized through dispersing the filler (15.5 %, w/w) into polymer matrix. The polymers and respective PNCs were characterized through various analytical methods. The graphite based electrodes were fabricated from polymers and respective PNCs in presence of sulphonated polyulphone binder. Supercapacitance and electrochemical stability of the electrodes were investigated through cyclic voltammetry (CV), electrochemical impedance spectra (EIS) and potentiodynamic polarization in KOH (1.0M). CV@ 0.001 to 0.2 V/s in the potential range -0.6V to 0.0V, reveals ranges of Cs for PIN, C60 , WC as 106.75 to 6.75 ,110.005.00 and 113.25-5.75 respectively. Under identical conditions, PNCs of PIN containing C60 and WC has shown Cs in the range of 296.75 to 5.00 and 490.00 to 5.50.MOF shows Cs ranging 283.63 -11.50. Modification of MOF with C60 results PNCs with highest Cs in the range of 494.50-32.63.All Cs data were found stable to 100 cycles. DC Polarization data in combination with microscopy reveals delamination of the coating of PIN based electrodes containing C60 and WC. Whereas, the electrodes derived from MOF containing C60 were highly resistant towards delamination under potentiodynamic condition. Modification of MOF based electrodes with C60 display higher Cs and inhibition efficiency over those modified with PIN. The present study provides a pioneer attempt towards synthesis and characterization of the C60 and WC based electrically conducting polymers for electrochemical energy storage.ThesisItem Open Access Nonisothermal kinetics and thermodynamics of solid-state decomposition of polyacrylamide/ferrite nanocomposites(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Arya, Meenakshi; Zaidi, M.G.H.The present research work deals with investigation of nonisothermal kinetics and thermodynamics of solid state decomposition of selected polyacrylamide derivatives and their polymer nanocomposites (PNCs).The PNCs investigated for this purpose were those containing ferrite nanoparticle (FNPs) with two different sizes (nm) viz; 10.5 and 21.5.Thermal characteristics of FNPs, homopolymers and respective PNCs was investigated through simultaneous thermogravimetric-differential thermal analysis-differential thermogravimetry (TG-DTA-DTG) in air. Data obtained from TGA were used to investigate kinetics of thermal decomposition process by applying Coats –Redfern (CR) and Horowitz Metzger (HM) methods. TG data reveals that the thermal stability of FNPs was regulated with size. In general, FNP-I with small size (10.50 nm) was more stable over FNP-II (21.15 nm). PNIPAM has shown highest thermal stability, followed by PDMAEMA and PAEMA. In general, HM methods have shown higher values of activation energy over CR method. Both the methods have provided a wide difference for Ea and A but identical results for entropy change and enthalpy change for most of the thermal degradation processes.ThesisItem Open Access Synthesis and biological activity of hexahydropyrimidine and carbamate derivatives(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Hussain, Aman; Kasana, VirendraHexahydropyrimidine derivatives have been synthesized by the reaction of different 1,3dicarbonyl compounds, aniline derivatives and formaldehyde catalysed by Calcium chloride dehydrate under solvent free conditions at room temperature. calcium chloride dihydrade offers simple, efficient and economical method. The compounds synthesized were 5-acetyl-1,3-diphenylhexahydropyrimidine-5-ethyl ester, 5-acetyl-1,3-bis(2-chlorophenyl)-hexahydropyrimidine-5-ethyl ester, 5-acetyl-1,3bis(4-fluorophenyl)-hexahydropyrimidine-5-ethyl ester, 5-acetyl-1,3-bis(2chlorophenyl)-hexahydropyrimidine-5-methyl ester, 5-acetyl-1,3-bis (2,4-dimethylphenyl) hexahydropyrimidine-5-ethyl ester, 5-acetyl-1,3-bis(4-hydroxyphenyl)-hexahydropyrimidine-5ethyl ester, 5-acetyl-1,3-diphenyl-hexahydropyrimidine-5-methyl ester, 5-acetyl-1,3-bis(4fluorophenyl)-hexahydropyrimidine-5-methyl ester, 5-acetyl-1,3-bis(2,4-dimethylphenyl)hexahydropyrimidine-5-methyl ester, 5-acetyl-1,3-bis(4-hydroxyphenyl)-hexahydropyrimidine-5methyl ester, 9,9-dimethyl-1,3-diphenyl-1,3-diazaspiro (5.5) undecane-7,11-dione. All the compounds were formed in good to excellent yield. Carbamates have been synthesized by the reaction of substituted benzeldehyde, acetophenone derivatives, malononitrile and diethyl-carbonate using organocatalyst proline under solvent free conditions at 400C. The compounds synthesized were ethyl-N-(2,6 dicyano-3,5-diphenylphenyl) carbamate, ethyl-N-[2,6- dicyano-3-(4fulorophenyl)-5 phenyl phenyl] carbamate, ethyl-N-[2,6 dicyano-3-(4-hydroxyphenyl)-5-phenyl phenyl] carbamate, ethyl-N-[2,6- dicyano-3-(4-methoxyphenyl)-5-phenyl phenyl] carbamate, ethyl-N-[2,6- dicyano-3-(dimethyl amino phenyl)-5- phenyl phenyl] carbamate, ethyl-N-[2,6dicyano-3-(2-nitrophenyl)-5-phenyl phenyl] carbamate, ethyl-N-[2,6- dicyano-3-(4-nitrophenyl)-5phenylphenyl] carbamate, ethyl-N-[3-(4-chlorophenyl)-2,6dicyano-5-phenylphenyl] carbamate, ethyl-N-[2,6-dicyano-3-(4-hydroxyphenyl)-5-phenylphenyl] carbamate, ethyl-N-[2,6- dicyano-3(2-hydroxyphenyl)-5-phenylphenyl] carbamate, ethyl-N-[3-(2-chlorophenyl)-2,6-dicyano-5phenylphenyl] carbamate. Most of the compounds were formed in good to excellent yield. The present work clearly establishes the efficacy of catalysts as an inexpensive, non-toxic, easily available and environmentally benign for the synthesis. All the compounds were tested for seed germination inhibition activity. Most of derivatives of hexahydropyrimidine were found to exhibit significantly lower activity than standard butachlor. While all the carbamate derivatives were found to exhibit very good seed germination inhibition activity. Two carbamate compounds ethylN-(2,6-dicyano-3,5-diphenylphenyl) carbamate, ethyl-N-[2,6-dicyano-3-(dimethylaminophenyl)-5phenylphenyl] were found to exhibit activity at par with standard butachlor. Thus synthesized carbamates may be explored for the development of potential herbicides.ThesisItem Open Access Phytochemical analysis and biological activity determination of Zingiber roseum Rosc(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-07) Arya, Sureshkumar Premram; Om PrakashZingiber roseum was collected from Padampuri, Uttarakhand in the month of September-October, 2015. The essential oil was isolated from fresh seeds by hydrodistillation using Clevenger’s type apparatus. Essential oil and all extracts were analysed by GC-MS for their phytochemical composition. Extracts of seeds, rhizome and perianth obtained in organic solvent of different polarity were for their antifungal activity against two phytopathogenic fungi viz; Rhizoctonia solani and Fusarium accuminata, antioxidant assay by different methods viz; reducing power activity, chelating activity of Fe2+, DPPH radical scavenging activities. All the methanolic extracts were studied for their qualitative analysis of phenolics by HPLC and herbicidal activity on Raphanus sativus (radish). The dried and powdered seeds, rhizomes and perianth were studied for their mineral profiling with help of Atomic Absorption Spectroscopy (AAS). The GC and GC-MS analysis revealed the presence of β–cubene (13.4%), caryophyllene (12.6%) and neryl linalool isomer (24.06%) were identified as major compounds compounds in oil. However neryl linalool isomer, geranyl linalool isomer, β-citronellal, 9-octadecenoic acid, l-(+)-ascorbic acid 2,6dihexadecanoate, 2-(4-hydroxy-3-methoxyphenyl)-3,7-dimethoxy-4h-chromen-4-one, 9,12-octadecadienoic acid (Z,Z)-, methyl ester and hexadecanoic acid, methyl ester were found major compounds in different extracts. HPLC analysis revealed the presence of ferullic acid, gallic acid and vanillic acid in different parts of plant. Extracts exhibited good to moderate antioxidant activity in dose dependent manner. Among all the extracts, Z. roseum perianth methanolic extract (ZRPME) possessed maximum DPPH radical scavenging activity; Z. roseum seed methanolic extract (ZRSME) showed maximum reducing power activity and maximum metal chelating activity was shown by Z. roseum perianth hexane extract (ZRPHE). Quantative analysis of total phenols, orthodihydric phenols and flavonoids ranged from (0.16±0.0 to 4.5±0.0 mg/g GAE), (0.01±0.0 to 4.4±0.0 mg/g CLE) and (11.5±0.0 to 78.2±0.01 mg/g CNE) in different extracts respectively. All extracts were found to be active against both fungi. All methanolic extracts inhibited the fungal mycelial growth of F. accuminata, while the extracts also possessed fungal growth promoting against R. solani. Z. roseum seed methanolic extract (ZRSME) was found most effective for inhibiting the growth of fungus. The extracts inhibited and promoted mycelial growth in respective fungi in dose dependent manner. The methanolic extract of Z. roseum were found to be active and inhibited the germination in the seeds of R. sativus (radish) and Z. roseum rhizome methanolic extract ZRRME showed more seed germinating activity than Z. roseum seed methanolic extract (ZRSME). Elemental analysis of various parts revealed the presence of Fe, Mn, Zn, Cu, Mg, Cd, Cr, N, P and K in varying quantities. Based on the above results it can be concluded that Zingiber roseum can be a good source of natural antioxidant, anti-fungal and herbicide after proper clinical trials besides its academic importance.ThesisItem Open Access Persistence of Imidacloprid insecticide in okra and its harvest time residue in paddy crop and soil of tarai region(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-06) Dhiman, Megha; Srivastava, AnjanaThesisItem Open Access Square wave voltammetric detection of isoproturon at nanocomposite electrode(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-07) Bhatt, Priya; Zaidi, M.G.H.ThesisItem Open Access Chemical diversity, genetic profiling and antioxidant activity of Acorus calamus L. accessions from different altitudinal regions of Uttarakhand(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-08) Chaubey, Pinky; Om PrakashIn present study the chemical composition of essential oils, total phenol analysis, antioxidant activity, elemental profiling, and genetic variability among the twenty collections of Acorus calamus from different altitudinal zones were evaluated. GC-MS analysis of essential oils of Acorus calamus exhibited the presence of various phenylpropanoids, monoterpenoids and sesquiterpenoids. The yields of essential oils varied from 0.2-1.4% and 0.7- 5.4 % (v/w) the oils of A. calamus leaves and rhizomes respectively. The major components identified in A. calamus essential oils from leaves and rhizomes were β-asarone, α-asarone, Z-methyl isoeugenol, Z-isoelimicin, and shyobunone. The presence of asaronaldehyde could be detected only in the rhizome samples from Chhoi, Nainital (2.4%) and Palpur, Almora collections (0.6%). Several minor constituents were also identified in the oils investigated. The antioxidant activity of rhizomes essential oil was studied by their ability to scavenge free radicals (IC50=22.27 to 61.96 µg/mL), metal chelating activity (29.55 to 159.26 µg/mL) and reducing power activity (21.41 to 61.19 µg/mL) whereas the antioxidant activity of leaf essential oil were evaluated by DPPH radical scavenging method with different IC50 values ranging from10.79 to 106.44 µg/mL in comparison to standard antioxidant. The methanol and hexane extracts were screened for their in vitro antioxidant activity and biochemical assay. All the extracts were also subjected to quantitative analysis of total phenols, flavonoids and orthodihydric phenolic contents. The total phenols, flavonols and orthodihydric phenols in all the methanolic extracts were ranged from 1.67 to 10.42 mg/g gallic acid equivalent, 0.50-27.25 mg/g catechin equivalent and 0.43- 5.50 mg/g catechol equivalent respectively. The antioxidant activity of methanolic extracts of A. calamus were evaluated by the three methods viz. DPPH radical scavenging, metal chelating and reducing power activity in terms of IC50 values were 143.55 to 919.55 µg/mL, 308.57 to 1439.35 µg/mL, 104.62 to 241.81 µg/mL respectively. The antioxidant activity of the hexane extracts also exhibited DPPH radical scavenging activity (IC50 = 113.05 to 1671.05 µg/mL), metal chelating activity (IC50 = 298.46 to 1141.46 µg/mL) and reducing power activity (IC50 = 105.86 to 307.50 µg/mL). In all the cases the activity observed were less than standard compounds BHT, catechin, EDTA and citric acid. The elemental analysis of leaves and rhizomes of A. calamus were studied with the help of atomic absorption spectrometry (AAS). The results exhibited the presence of P, K, Ca, Na, Mg, Mn, Fe, Cu, Cr, Pb, Ni, and Zn. The genetic diversity by simple sequence repeat revealed the monomorphic behaviour of the plant.