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Open Access
Development and characterization of rare earth oxide-polypyrrole nanocomposites
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-08) Rekha; Sand, N.K.
A series of rare earth oxides (REOs)/polypyrrole (PPY) nanocomposites (RPCs) were synthesized through surfactant assisted chemical oxidative polymerization. The polymerization was followed by blending pyrrole with REOs at various concentration ranging 7 to 21 (%, w/w). For this purpose, REOs selected were Ho2O3 and Er2O3. RPCs were characterized through fourier transformed infra-red, X-ray diffraction, energy-dispersive spectra, atomic force, scanning electron microscopy (SEM), simultaneous thermogravimetric-differential thermal analysis-differential thermogravimetry and cyclic voltammetry. Semiconducting behaviour of electrodes derived from PPY and RPCs was investigated from 298 to 393K at selected voltages. Electrodes derived from PPY show semiconducting behaviour with DC conductivity (σ DC, mS/cm) ranging 1.94–292.95. Under identical conditions, electrodes derived from Ho2O3 and Er2O3 display σ DC in the range of 2.61-534.87 and 2.31-475.89 respectively. Simultaneous imaging of electrodes during temperature regulated σ DC measurements through SEM reveals thermal stability of electrodes in the range of 353 to 373K. Cyclic voltammetry (CV) in combination with DC polarization reveals electroactive nature of electrodes, that was increased with concentration and nature of REOs. In general, electrodes derived from Ho2O3 display improved semiconducting, electrochemical behavior and controlled rate of corrosion over Er2O3 electrode. The present study delivers method of fabrication of electrodes for semiconducting and electrochemical applications.
Open Access
Chemical and genetic profiling of various lentil (Lens culinaris Medik.) genotypes and their pharmacological attributes
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-02) Belal, Babita; Vivekanand
In the present investigation, 28 lentil (Lens culinaris Medik.) genotypes were evaluated for their chemical composition, biochemical profile, pharmacological attributes, nutritional potential, anti-nutritional traits, and genetic profile. GC-MS analysis of lentil methanolic extracts revealed the identification of various phytoconstituents representing about 51.76-91.43% of the total extract. Highest percentage contribution of phytoconstituents (91.43%) was observed in PL-4. Fatty acids and fatty esters were identified as the dominant constituents in addition to several minor components. The total phenolic, flavonoid, orthodihyric phenol, proanthocyanidines and tannin content was found in the range of 6.76-12.14 mg GAEg-1, 1.49-3.08 mg CAEg-1, 0.53-2.11 mg CLEg-1, 1.56-5.56 mg CAEg-1 and 2.58-7.22 mg TAEg-1 respectively. Genotype PL-259 exhibited the highest DPPH (IC50=498.83 μg/ml) and hydroxyl (IC50=599.08 μg/ml) radical scavenging activity. The maximum nitric oxide scavenging was observed in DPL-15 (IC50=419.29 μg/ml) while superoxide scavenging activity was highest in PTH (IC50=542.14 μg/ml). UPL-175 was found to exhibit maximum chelating activity (IC50=585.51). FRAP activity was found the maximum in genotype PL-5. All lentil methanolic extracts were found to be effective against gram-positive (Staphylococcus aureus and Bacillus subtilis) and gram-negative (Salmonella typhiand Escherichia coli) bacterial strains in dose-dependent manner. Proximate composition analysis in terms of ash, crude fiber, protein, and carbohydrates content showed a rich nutritional potential of lentil genotypes. The content of macro and micro-nutrient was evaluated by AAS and their magnitude was observed to be laid in the following order: K>Mg>Na>Ca>Fe>Zn>Mn>Cu>Ni>Co. Antinutritional factors like phytic acid and trypsin inhibitors have been evaluated in all lentil genotypes. Genetic variability among lentil genotypes was determined by microsatellite markers.
Open Access
Carbide modification of polypyrrole for electrochemical energy storage
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-08) Bisht, Anjali; Zaidi, M.G.H.
A series of carbide/conducting polymer based electrode materials (EMs) were synthesized through surfactant assisted dilute solution polymerization in presence of ferric chloride oxidant. For this study,pyrrole was selected as monomer whereas silicon carbide (SiC) and tungsten carbide (WC) were selected as fillers. The formation of polypyrrole (PPY) and respective EMs comprising SiC and WC (21 %,w/w) was ascertained through Fourier transformed infra-red (FTIR), X-ray diffraction spectra (XRD), Simultaneous thermogravimetric-differential thermal analysis–differential thermogravimetry (TGA-DTG-DTA) and scanning electron microscopy-energy dispersive X-ray (SEM-EDX).Working electrodes (WEs) were fabricated to investigate the utility of EMs towards electrochemical energy storage. In general, PPY and respective EMs have shown the charging and discharging close to a rectangular shape and there is no current peak caused by a redox reaction, indicating a typical supercapacitivebehaviour with good charge propagation till 100 cycles. With scan rate, the ranges for Cs (F/g) of WE derived from SiC, WC and PPY were observed as 11.00 to 334.20, 13.20 to 435.20 and 10.80 to 323.20 respectively in the potential range of -0.7 to -0.2 V. With concentration of SiC, the respective EMs have shown CS ranging 368.00 to 620.80 F/g at 0.001 V/s. Under identical conditions, the Cs of EMs derived from WC was in the range of 563.20 to 716.80 F/g. The stability of WEs derived from PPY and respective EMswere investigated under electrochemical impedance spectroscopy and potentiodynamic polarization. The polarization data monitored through SEM-EDX reveals change in the morphology of PPY and respectiveEMs. The present study provides a pioneer attempt towards development and characterization of carbide modified conducting polymer for electrochemical energy storage.
Open Access
Persistence, degradation and leaching behavior of penoxsulam herbicide in soils of different characteristics
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-12) Monika; Srivastava, Anjana
Penoxsulam is a post-emergence, triazolopyrimidinesulfonamide group of herbicide,used to control broadleaf and sedges weeds in rice crop. Thedissipation, persistence and leaching behavior of this herbicidewas investigated under laboratory conditions. Dissipation study of penoxsulam was performed in two soil samples at two concentrations i.e. 0.5 and 1.0 μg g-1 under non flooded conditions (20% moisture regime)and 1.0 and 2.0 μg g-1 under flooded conditions (submerged conditions). Penoxsulam was extracted by two methods (simplified QuEChERSmethod as well as long traditional method).The analysis of the herbicide was done by high performance liquid chromatography (HPLC). The average recoveries of penoxsulam in soil ranged between 88.4 and 89.6%at lower application (0.5 μg g-1) rate and 93.6 and 95.5% at higher application (1.0 μg g-1) rate. Penoxsulam residues declined consistently with time in both the type of soils under both the conditions. At lower application rate (0.5 μg g-1) penoxsulam declined continuously persisting up till 21st day with dissipation up to 75.0% and 72.3% in the two soil samples while at higher application rate (1.0 μg g-1) it persisted up till 30th day dissipating up to 73.4% and 74.5% in the two soil samples under non flooded conditions. However, under flooded conditions the herbicide declined slowly persisting up to 30th day with dissipationup to 80.6% and 77.2% in the soil samples at lower application rate (1.0 μg g-1) and at higher application rate (2.0 μg g-1) it persisted up to 60th day with dissipation up to81.6% and 80.0% in the soil samples.Penoxsulamwas not detectable(ND) i.e. < 0.004 μg g-1 on 30thand 60thday of herbicide’s application in both the type of soils at lower and higher application rates respectively under non flooded conditions whereas, underflooded conditions it was ND on 60th and 90th day of application.Dissipation of penoxsulam occurred in a single phase with the persistence data fitting well with the first-order kinetics. The half-life of penoxsulam was 3.48 and 3.57 d at lowerapplication rate in the two soils and 4.10 and 4.17 d in both the type of soils at higher application rateunder non flooded conditions.Under flooded conditions the t1/2 values in both the soil samples were 5.50 and 6.93 d at lowerapplication rate and 10.0 and 10.19 at higherapplication rate. Penoxsulam does not persist for long time at lower concentration but is more persistent at higher concentration in both the subtropical soil under both the conditions. The degradation products and metabolites of penoxsulam were identified by LC MS/MS analysis. Leaching experiment of penoxsulam was also conducted in two soils at two application rates (0.5 and 1.0 μg g-1)via batch method. The presence of penoxsulam was very low in the first and third leachate but it was determined in high amount in the second leachate, which was collected after 72 hours of leaching initiation. The residues of penoxsulam in leachate of acidic soil were slightly lower than that of neutral soil probably because of higher stability of the herbicide at low pH.
Open Access
Phytochemical analysis and biological activities of some plants of family Verbenaceae, Lauraceae and Myrtaceae
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-11) Joshi, Archana; Pant, A.K.
The essential oils and methanolic extracts of various species of family Myrtaceae, Verbenaceae and Lauraceae were analyzed for chemical composition, total phenol content, antioxidant activity and biological activities. The major components identified in the essential oil of Melaleuca leucadendron (L.) were E-nerolidol (85.7%), caryophyllene oxide(3.7%) and benzaldehyde(1.2%) besides other minor constituents. 1,8-cineol (61.1%), α-terpineol (12.3%), α-pentene (4%) and β-myrcene (3.8%) along with other minor constituents were identified in the leaf essential oil of Melaleuca.linariifolia Sm. The major compound in the leaf essential oil of Melaleuca bracteata F.Muell were methyl eugenol (74.8 %) and E-methyl cinnamate (7.97%) accompanied with other minor constituents. The leaf and flower essential oils of Callistemon viminalis (Sol. Ex Gaertn.) G. Don were characterized by dominance of 1,8-cineol (40 % and 65.4%) followed by α-pentene (17.3% and 12%) and α-phellendrene (11.8% and 4.3%) alongwith other minor constituents respectively in leaf and flower oil. Linalool (65.7% and 63.8%) was detected as the major component of two morphotypes of Lippia alba(Mill.) N.E.Br.ex Britton & P. Wilson. The major compounds in Caryopteris odorata (D. Don) Robin essential oil were β-caryophyllene (33.1%), α-bisabolene (11.0%), β-elemene (7.0%), β-caryophyllene oxide (6.0%) and β-longipinene (4.0%). The essential oils from leaf, stem and seeds essential oil of Caryopteris foetida (D. Don) P. D. Cantino were characterized by the presence of spathulenol, β-caryophyllene and δ-cadinene alongwith other minor constituents respectively in the leaf, stem and seed essential oil. The major component of the leaf oil of Litsea lanuginosa (Nees) were ethyl ester of tetradec-tetraenoic acid (16.8%), β-caryophyllene oxide (10.8%), spathulenol (4.9%) and caryophylla-4(12),8(13)-dien-5β-ol (4.9%) besides other minor constituents. The major compound in the leaf essential oil of Litsea monopetala (Roxb.) Pers. were furanodiene (60%) and sesquirosefuran (14.3%) besides other minor constituents. β-caryophyllene (15.5%) and (E)-β-ocimene (13.88%), β-myrcene (6.6%) were identified as major componenets in the leaf essential oil of Litsea glutinosa (Lour.) C.B Robinson along with other minor constitutents. Two chemotypes of Litsea umbrosa (Nees) Nees syn. Neolitsea pallens were studied. The major compounds identified in the essential oil of L.umbrosa type I were furanogermanone (13.8%) and sabinene (5.4%) whereas in type II β-pinene (7.4%) and β-eudesmol (5.6%) were found alongwith other minor constituents. Among the major compounds identified in the methanolic extracts, (E,Z)-nerolidol (24.7%), betulinic acid (13.6%) and ursolic acid (6.3%) were identified in M.leucadendron. Betulinic acid (9.9%), quinic acid (6.4% and gallic acid (1.1%) in M.linariifolia while betulinic acid (13.4%), ursolic acid (4.3%) and quinic acid (3.1%) in M.bracteata were the major compounds . Phytol (2%), palmitic acid (1.7%) and α-linolenic acid (1.3%) in C.odorata, glycerol (6.0%) and ribitol (3.0%) in C.foetida were the major components. pinitol (17.4%), quinic acid (2.4%) and cyclohexanepentol (6.6%) in L.lanuginosa, α-tocopherol (2.7%), phytol (2.4%) and palmitic acid (2.5%) in L.monopetala, α-tocopherol (9.2%), β-sitosterol (5.7%), palmitic acid (6.1%) and phytol (3.5%) in L.glutinosa, shikimic acid (13.1%), betulinic acid (7.3%), ursolic acid (6.7%), gallic acid (7.1%), quinic acid (4.5%) and oleanolic acid (3.0%) in C.viminalis were identified as TMS derivatives. The methanolic extracts were subjected to quantitative analysis of total phenol, flavanoids and orthodihydric phenol content. The phenol content, flavanols and orthodihydric phenols were found to vary from 9.07 to 35.12 mg/g GAE, 5.18 to 29.09 mg/g CTE and 0.89 to 31.88 mg/g CLE. The antioxidant activity of methanolic extracts and essential oils were determined in terms of radical scavenging , iron chelating, reducing power assay and total antioxidant activity. The DPPH radical scavenging activity of methanolic extracts and essential oils (in terms of their IC50 values) varied from 40.85 to 131.49 μg/ml and 1.82 to 26.88 μg/ml respectively. The methanol extract of M.linariifolia exhibited maximum (IC50=40.85±2.501μg/ml) DPPH radical scavenging activity whereas the essential oil of C.odorata (IC50=1.82±0.042 μg/ml)showed strong DPPH radical scavenging activity. The metal chelating activity of methanolic extracts and essential oils were found between 139.15 to 309.82μg/ml and 1.59 to 28.30μg/ml respectively. The methanolic extract of L.lanuginosa (IC50=139.15±0.761 μg/ml) and essential oil of C.odorata (IC50=1.59±0.456 μg/ml) revealed strong iron chelating activity. The reducing power activity of methanolic extracts and essential oils were found in the range of 80.37μg/ml to 264.78 μg/ml and 2.11μg/ml to 15.98μg/ml. The maximum (IC50=80.37±0.787 μg/ml) reducing potential was exhibited by methanol extract of C.odorata whereas the essential oil of M.bracteata (2.11±0.390 μg/ml) exhibited remarkably strong reducing activity. The nitric oxide radical scavenging activity of methanolic extracts and essential oils were found to vary between 65.74 to 192.37μg/ml and 12.46 to 42.19μg/ml. The total antioxidant activity of methanolic extracts were found to vary between 20.52 to 92.73 μg/ml and maximum (92.73 μg/ml) was found in leaf methanolic extract of C.foetida. The invitro anti-inflammatory activity of essential oils and methanol extracts were determined and compared with standard Diclofenec sodium. A remarkably strong anti-inflammatory activity was exhibited by the leaf essential oil and methanolic extract of C.foetida. The essential oils and extracts were also analyzed for antifungal and antibacterial potential. The essential oil of M.leucadendron inhibited 80.83% whereas M.bracteata inhibited 82.91% of mycelia growth of Sclerotinia. Also the essential oil of M.bracteata inhibited 90% mycelia growth of E.turcicum along with significant reduction in the growth of C.lunata (75.20%). Most of the extracts and essential oils revealed antibacterial activity against tested microorganism. The methanolic extract of Litsea monopetala and Litsea glutinosa exhibited MIC of 200ppm against Salmonela typhimurium.The methanolic extract of Callistemon viminalis revealed strong antibacterial activity with MIC of 200ppm,150ppm and 150ppm respectively against E.coli , Staphylococcus aureus and Basilus megaterium.Similarly the essential oil of Litsea monopetala ,Lippia alba ,Melaleuca bracteata exhibited strong activity. Allelopathic activity of essential oils and methanolic extracts was determined in terms of inhibition of seed germination and percent reduction of radical elongation of radish seeds. All the extracts and essential oils exhibited moderate to strong herbicidal activity at all tested concentrations. Based on above findings it can be concluded that the species under study can be used as a potent source of various marker constituents of industrial and pharmaceutical applications as well as a good source of natural antioxidant, antimicrobials and organic herbicide.
Open Access
Development of green methodologies for the synthesis of some biologically active heterocyclic and β- amino carbonyl compounds
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-05) Bhandari, Suneeta; Kasana, Virendra
A series of chromene, indenochromene, oxazolone and β-amino carbonyl compounds have been synthesized using mild catalytic systems. Camphor-10-sulphonic acid has been used as an efficient organo-catalyst for the synthesis of chromene and indenochromene compounds. Oxazolone derivatives have been synthesized using L-proline as an organocatalyst via aldol condensation reaction. Fe3+-montmorillonite K10 clay, a solid supported heterogeneous recyclable, efficient and environmentally benign catalytic system has been developed for the synthesis of β-amino carbonyl compounds. Ionic liquid supported on silica nanoparticles (SILnPs) has been developed as an efficient and economical solid supported recyclable catalyst for one-pot three component direct synthesis of β-amino carbonyl compounds via Mannich type reaction. The structures of catalytic systems have been characterized using SEM, TGA, powder XRD, FT-IR methods. The structures of synthesized compounds have been elucidated using FT-IR, 1H NMR, 13C NMR and single X-ray crystallography. Further, oxazolone derivatives were studied for herbicidal activity against Raphanus sativus. β-amino carbonyl were studied for herbicidal activity against weeds Melilotus alba and Lathyrus aphaca. Most of the tested compounds of these two classes were found to exhibit good herbicidal activity. β-amino carbonyl derivatives were also studied for antibacterial activity against two human pathogenic bacterial strains Escherichia coli and Bacillus subtilis. The compounds 3-((4-fluorophenyl)amino) -3-(3-methoxyphenyl)-1-phenylpropan-1-one (20f) and 3-((4-chlorophenyl)amino)-1,3-diphenylpropan-1-one (20h) were found to have good antibacterial activity.
Open Access
Biochemical profiling and antimicrobial screening of some Citrus species collected from Uttarakhand
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-08) Om Prakash; Vivekanand
Citrus species are the member of Rutaceae family which includes flowering trees and shrubs like oranges, lemons, grape fruit and limes. They posses several health promoting properties due to the presence of some bioactive secondary metabolites like Polyphenols, having several nutritional and antioxidants potential. The present study was undertaken with the objective of, biochemical profiling, genetic profiling, antibacterial screening and herbicidal activity of methanolic extract of peel of four different citrus species (Citrus jambhiri, Citrus lemon, Citrus aurentifolia, and Citrus sinensis) collected from 4 different districts of Uttarakhand. GC-MS analysis of extracts showed significant variation in their phytoconsitituents. Maximum 92.99 % compounds identified in Citrus jambhiri (Pithoragarh), 78.80 % in Citrus jambhiri (Almora), 84.54 % in Citrus sinensis (Nainital) and 93.37 % in Citrus aurantifolia (Rudraprayag). Total phenols, flavonoides and tannin are ranging from 46.9±1.11 to 20.10±0.20 mg/g GAE, 58.04±2.49 to 19.21±04 mg/g CNE, and 30.06±2 to 4.23±1.45 mg/g TAE respectively. A significant antioxidant potential was shown in all species in a dose dependent manner. A significant antibacterial activity of citrus sp. was evaluated against various gram positive and gram negative bacteria. The order of magnitude of macro and micro essential elements is Na>Fe> Ca> Zn> Ni> Cu> Mn> Co. Metal complexes of Rutin and bioconjugate of citrus peel extract showed moderate to highs herbicidal activity against Lathyrus aphaca and Mellitus alba. SSR primer technique was performed to study genetic diversity among Citrus accessions. Metal complexes of Rutin and bioconjugate of Citrus peel extract also exhibit strong antioxidant and herbicidal activity.
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 Prakash
In 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.
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 Nand

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