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ThesisItem Open Access Characterization of nanoferrogels for electroanalysis of control release Simazine(G. B. Pant University of Agriculture and Technology, Pantnagar, 2022-05) Joshi, Pragati; Zaidi, M.G.H.Present thesis demonstrates supercritical synthesis of nanoferrogels (NFGs) derived control release formulations (CRFs) of simazine (SZ). CRFs were synthesizedthrough free radical polymerization of selected acrylamide derivatives in presence of bisacrylamide in supercritical carbon dioxide (SCC). Ferrite nanoparticles with crystallite size (10.5 nm) were synthesized through chemical methods and employed for synthesis of NFGs. Thesis further demonstrates the development of working electrodes (WEs) from supercritically synthesized polypyrolle/ graphene oxide (PPY/GO) nanocomposites for detection and quantification of SZ released from CRFs. All polymerization reactions leading to synthesis of CRFs were conducted at common temperature, pressure and time. Square wave voltammetry (SWV) has been employed as a novel and viable alternative to spectral and chromatographic methods for monitoring of SZ release from CRFs. Formation of all synthesized products were ascertained through diverse analytical methods. SWV was conducted over triple electrode assembly constituting Ag/AgCl as reference, platinum foil of 1cm2 area as counter electrode coupled with WEs in KCl (0.1M, pH3.5). WEs has rendered limits of detection (Molar): 2.92 × 10-10 and quantification: 9.03 × 10-10 of SZ in KCl (0.1 M, pH 3.5). Cyclic voltammetry reveals enhanced electrochemical response of WEs towards release of SZ from NFGs over HGLs based CRFs. Potential of NFGs towards SZ release was compared with analogous HGLs derived CRFs under identical electrochemical conditions over 6h. SWV reveals 60-80% release of SZ from HGLs derived CRFs. Whereas, NFGs derived CRFs has rendered remarkable slow release of SZ by 45-55%. Developed CRFs may find their future applications in conditioning of drought affected agricultural fields along with simultaneous control release of herbicides through supercritically produced CRFs for future sustainable agriculture. Moreover, high thermal stability of synthesized materials may improve their shelf life in thermally activated soil media.ThesisItem Open Access Phytochemical characterization and evaluation of different biological activities of Mosla dianthera (Buch.-Ham. ex Roxb.) Maxim. and Plectranthus barbatus Andrews(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2020-02) Kanyal, Jeewanti; Om PrakashIn present study the chemical composition by GC/MS, isolation of the compounds by column chromatography, characterization of isolated compounds by spectroscopic techniques, biochemical assay and their different biological activities like antioxidant, in vitro antiinflammatory, herbicidal, antibacterial, antifungal and antifeedant activities of essential oils, various extracts and isolated compounds from Mosla dianthera and Plectranthus barbatus were evaluated. The yields of essential oils and extracts from M. dianthera and P. barbatus were observed 0.1-0.4% and 1.3-12.0% respectively. Carvone, n-decanal, (-)-bornyl acetate, capric aldehyde, thymol, p-cymene, β-pinene and α-pinene were identified as major components in essential oils. Cellobiose, forskolin, tetrapentacontane, thymoquinol, palmitic acid, γ-sitosterol, 2-ethyl-5-isopentylthiophene, 5-hydroxymethylfurfural and (Z)-9-octadecenal were identified as major components in extracts. The isolation of the compounds from aerial part essential oil of M. dianthera and root part ethyl acetate extract (polar fraction) of P. barbatus by column chromatography and characterization by FT-IR and NMR proofed the presence of carvone and forskolin respectively. The total phenolics, flavonoids and orthodihydric phenols in the extracts were found to vary from 13.72 to 47.72 mg/g gallic acid equivalent, 10.65 to 71.73 mg/g catechin equivalent and 4.55 to 10.27 mg/g catechol equivalent respectively. The antioxidant assay was evaluated by six different methods. The essential oils, extracts and isolated compounds exhibited antioxidant potential in a dose dependent manner. The in-vitro antiinflammatory activity of essential oils, extracts and isolated compounds was evaluated by using protein (albumin) denaturation method. A remarkable anti-inflammatory potential was exhibited by isolated compound forskolin (89.40%) and aerial part chloroform extract of M. dianthera (88.03%). The herbicidal activity was determined in term of inhibition of seed (radish) germination. All the essential oils, extracts and isolated compounds showed moderate to strong herbicidal potential in a dose dependent manner. The essential oils, extracts and isolated compounds exhibited significant antibacterial activity against two pathogenic bacteria. Among all, isolated compound forskolin was found to most effective against B. cereus and E. coli. Similarly, the antifungal activity of essential oils, extracts and isolated compounds was tested against two phytopathogenic fungi and express in term of inhibition of mycelial growth of fungi. The essential oils were found more effective for inhibiting the growth of fungus. Among all, aerial part essential oil of M. dianthera exhibited maximum inhibition (100%) of mycelial growth of A. alternata and C. lunata at higher concentration (500 ppm). The antifeedant activity was evaluated by using leaf disc method in no-choice situation. All the essential oils, extracts and isolated compounds exhibited a diverse category of antifeedant activity (moderate to extreme antifeedant). Among all, the maximum antifeedant activity was observed in aerial part essential oil of M. dianthera (90.70%), followed by isolated compounds carvone (89.17%) and forskolin (87.60%) against S. obliqua (Bihar hairy caterpillar) larvae.ThesisItem Open Access Studies on N-arylsulfonamides containing thiophene and chromene moieties for their synthesis and antibacterial activity(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-02) Ajay Kumar; Kasana, VirendraN-arylsulfonamide derivatives containing thiophene, chromene and benzoxazole substituted chromene moieties were synthesized. N-substituted amino derivatives containing thiophene moiety were prepared by multi-component reactions (MCR) of substituted benzaldehydes, benzyl cyanide, malanonitrile and sulfur using organic catalyst L-proline. Multi-component reaction of substituted benzaldehydes, phenol and malanonitrile were catalyzed by L-proline afforded N-substituted amine derivatives containing chromene moiety. Benzoxazole substituted chromene moiety containing amino derivatives were synthesized from starting materials malanonitrile and 2-amino phenol to afford 2-(benzoxazol-2-yl) acetonitrile which was further reacted to phenol and substituted benzaldehydes using L-proline as catalyst to afford amino derivatives. The L-proline has been used as organocatalyst for these reactions first time. All above mentioned three different classes of amino derivatives were reacted with p-toluene sulfonyl chloride to afford final amide products. The synthesized compounds were evaluated for their antibacterial activity against Salmonella typhinurium, Escherichia coli and Staphylococcus aureus pathogenic bacterial strains. Some derivatives of synthesized compounds exhibited good antibacterial activity at concentration 10,000ppm. The thiophene, chromene and benzoxazole substituted chromene compounds synthesized may further be modified to develop a class of potential antibacterial agents.ThesisItem Open Access Chemoprofiling, biochemical and pharmacological screening of various fennel (Foeniculum vulgare Mill.) genotypes(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-02) Mehra, Nisha; Viveka NandThe present study deals with the investigation of 11 fennel (Foeniculum vulgare Mill.) genotypes were evaluated for theirchemical composition, phytochemical assays, nutritional profiling, pharmacological attributes and biological activity. GC-MS analysis in hexane and methanolic extract demonstrated the identification of various phytoconstituents representing 70.79-100% of the total extract. A higher percentage of phytoconstituents was observed in methanolic extract of FNL-PM (100%). Various fatty acids and fatty esters were identified as dominant constituents in addition to minor components. Total phenolic content in hexane, chloroform and methanol extract were ranged (1.43±0.40 to 7.10±0.51), (1.34±0.39 to 0.76±0.01) and (4.78±1.56 to 32.90±0.79) mg GAEg-1. Flavonoid content ranged in hexane extract (0.57±0.26to2.98±0.65),in chloroform extract (0.40±0.19 to 1.95±0.35)and methanol extract (0.57±0.13 to 11.92±1.86)mg CAEg-1.Orthodihydric amount in hexane extract is (1.36±0.14-31.to 75±0.08), in chloroform extract (1.34±0.35 to 49.41±4.3) and methanol extract (22.46±0.26 to 59.57±0.30) mg CLEg-1. Proanthocyanidine content in hexane extracts (0.55±0.24 to 15.59±0.28),in chloroform extract (0.88±0.55 to 22.42±0.21)in methanol extract (10.47±0.17 to 33.62±0.34)mg CAEg- 1. In hexane extract, total tannins content (3.01±0.10 to 5.52±0.07), in chloroform extract (1.03±0.03 to 7.47±0.32)and methanol extract (3.67±0.22 to 8.42±0.32) mg TAEg- 1.Maximum DPPH scavenging activity exhibited in the hexane extract of FNL-PM (IC 50 = 443.88±0.91 μg/ml). Maximum hydroxyl radical scavenging in methanol extract of FNL-117 (IC50=414.74±1.35 μg/ml). High superoxide radical scavenging in the hexane extract of FNL-126 (IC50=420.68±1.09 μg/ml). Maximum nitric oxide radical scavenging potential found in hexane extract of FNL-117 (IC50=557.03±0.86 μg/ml). Strong chelation observed in hexane extract of FNL-118 (IC50=563.07±0.07 μg/ml). The highest FRAP activity observed in the methanol extract of FNL-126 (8.08±0.008 μ mole/g). All fennel genotypes were observed to be effective against bacterial strains in a dose dependent manner while FNL-117 have no inhibitory action against any bacteria. Maximum α-amylase observed in the hexane extract of FNL-125 (IC50=227.77±0.64 μg/ml) and high α-glucosidase activity in the hexane extract of FNL-120 (IC50=230.02±0.62 μg/ml). Higher anti-inflammatory potential observed in the hexane extract of FNL-124 (IB50=663.22±1.98 μg/ml). Proximate analysis in terms of ash, moisture, crude fat, crude fibre, total protein and carbohydrate content showed a rich nutritional value in fennel genotypes. The macro and micro-nutrient were observed in order Ca> K> Mg>Fe> Na> Ni>Cu>Mn>Cr>Co. Fennel genotypes demonstrated moderate herbicidal potential.ThesisItem Open Access Phytochemical and pharmacological activities of Ficus auriculata leaf, bark and fruit from different agro-climatic conditions of Uttarakhand(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-02) Tamta, Garima; Tandon, ShishirThe present investigation conducted on fruits, leaves and bark of Ficus auriculata (Timul) collected from two agro-climatic conditions of Uttarakhand (Haldwani and Almora). Extract were done by successive soxhlet extraction method by three solvents viz. methanol, chloroform and hexane. Presence of alkaloids, terpenoids, saponins, fatty acids and glycosides were estimated by preliminary test. Phytoconstituent evaluated by GC-MS analysis showed various phytoconstituents in all extract. Some majore constituents were identified ƴ-sitosterol , lupeol, linoleic acid (methyl ester), kinic acid, phytol, oleic acid(methyl ester) and squalene. Several other fatty acids with minor phytoconstituents were also identified. Phenolics, Flavonoids, orthodihydric phenol, proanthocyanidin and tannin content were also found in good quantitiy. Fruits , leaves and bark were rich in nutritional potential including moisture, ash, crude fibre, crude fat, crude protein and carbohydrate contents. Elemental analysis were done by AAS to know micronutrients in plants and their quantity were present in the following order-: K>Mg>Ca>Fe>Ni>Na>Cu>Mn>Cr>Co. Antioxidant activity were done and the highest DPPH radical scavenging activity and hydroxyl radical scavenging activity were exhibited by AUFME (IC50 =447.45±0.53μg/ml) and (IC50 =463.7±1.55μg/ml) respectively. HRFHE exhibited maximum nitric oxide and super oxide radical scavenging activity (IC50 =487.5±1.82 μg/ml) and (IC50 =508.94±0.754 μg/ml) respectively. ARFHE exhibited maximum metal chelating activity (IC50 =483.95±3.21 μg/ml) while FRAP assay was found maximum in ABHE (IC50 =8.15 ±0.742 μmole/g). Fruits, leaves and bark extracts in methanol, chloroform and hexane exhibited the effective antibacterial potential against gram positive bacteria (Staphylococcus aureus and Bacillus subtilis) and gram negative bacteria (Salmonella typhi and Escherichia coli). In antidiabetic activity, AUFME exhibited maximum alpha amylase and glucosidase inhibitory activity (IC50 =240.45±1.26 μg/ml) and (IC50 =245.02±1.81 μg/ml) respectively. HUFME showed the maximum anti-inflammatory activity (IC50 =536.89±1.79 μg/ml). Herbicidal potential were shown maximum by AUFCE and HBCE and root growth inhibition found greater than shoot growth inhibition.ThesisItem Open Access Studies on substituted phenols and triazolopyrimidine sulfonamide herbicide(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2020-02) Gururani, Namrata; Srivastava, Anjana4-Nitrophenol and 2,4-dichlorophenol are two substituted phenols which are included in the priority pollutant list as chemical pollutants by United States Environmental protection agency (USEPA). The present study was undertaken to determine the utility of untreated and Fetreated Nostoc sp. as a potent biosorbent for the removal of these two phenols from wastewater. Adsorption –desorption, which is an efficient and cost effective method has been tried for removal of pollutants from wastewater. Thereafter, the kinetics of adsorption and effect of different state variables ( time, pH, concentration, ionic strength and temperature) on biosorption of phenols (4-NP and 2, 4-DCP) was conducted. The biosorbent (Nostoc sp.) was cultured in BG-11 medium and the dead dried biomass was obtained after filtration and drying. Part of this dried biomass was modified to Fetreated biomass by treatment with FeCl3(0.1 M ). The results obtained, suggested that the equilibration time for biosorption at different pH (4, 7, 9) was 12h with maximum sorption at pH 7 both on untreated and Fe treated biomass. Decrease in cumulative percent desorption from 11.25 to 0.47 for 4-NP and 1.83 to 0 percent for 2,4-DCP after treatment with iron showed the irreversibility of the biosorbent after iron treatment. Sorption data of phenols (4-NP and 2,4-DCP) was fitted to different models and pseudo second order kinetic model was found best with R2 value 0.999 (significant at p ≤ 0.01) in all the four cases (4-NP (untreated and Fe treated), 2,4-DCP (untreated and Fe treated). The effect of concentration was checked at four different concentrations (2, 4, 6 and 8 ppm) and the sorption data obtained fitted well to Freundlich adsorption isotherm indicating heterogeneous nature of binding sites on Nostoc. The Freundlich constants ln K and 1/n were also calculated and both were found to increase after treatment with iron for both the phenols. In order to see the effect of ionic strength two electrolytes ( CaCl2 and KCl at two concentrations were taken. Increase in ionic strength increased the biosorption of phenols probables due to the decreased thickness of the double diffused layer. Sorption studies at varying temperature (15, 25 and 35⁰C) revealed that increase in temperature decreased the biosorption indicating biosorption to be physical in nature. The FTIR investigation clearly revealed that functional groups like hydroxyl, aldehydic and nitro groups on the surface of the biosorbent were involved in the binding.SEM images of untreated and Fe treated Nostoc sp. showed elimination of cavities on the biosorbent surface after treatment with Fe3+ ions. Adsorption-desorption behaviour of penoxsulam in six different soils wasalso investigated under two state variables temperature and ionic strength. Physiochemical properties of soils were examined. pH showed strong correlation with adsorption of penoxsulam in soil. Among the six soils, three soils namely, LOH-5, HLD-1 and BH-1 were acidic in nature with pH below 6.5. Soil (HLD-2) was nearly neutral with pH 6.83 and two soils (BD-2 and JK-1) were basic with pH above 7.5. Adsorption in case of temperature and ionic strength was higher in acidic soils than in neutral and basic soils. Increase in temperature decreased the adsorption on each of the six soils, with maximum at 15⁰C followed by 25 and 35⁰C indicating adsorption to be physical in nature. Increase in ionic strength increased the adsorption which was significant at p≤ 0.05 in case of alkaline soils.The trends were attributed to the salting out phenomena.
