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Open Access
A green approach for the removal of Cadmium and Arsenic from synthetic waste water using Citrus limetta peels
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-06) Saumya; Viveka Nand
The study was undertaken to examine the biosorptive efficiency of Citrus limetta peels, collected from Bajpur, Udham Singh Nagar. Batch mode experiments were conducted to study the effects of contact time, pH and temperature on biosorption of Cadmium (II) and Arsenic (III) on Citrus limetta peels. Cadmium (II) and Arsenic (III) are major concern in the present study because the excessive intake of these metals leads to several health issues and are also carcinogenic. The maximum percentage removal (% removal) and biosorption capacity (Qe value) for Cd (II) was recorded at contact timing of 120 min, acidic condition (pH 4.9) and hot temperature (45±5°C) which was 73.80%. In case of As (III), maximum percentage removal was 82.1% observed at contact time of 120 min, neutral condition (pH 7.0) and hot temperature (45±5°C). In case of both Cd (II) and As (III), contact time of 120 min and hot temperature was favourable for metal removal. Langmuir, Freundlich and Temkin adsorption isotherm models were used to explain the adsorption phenomena of both the Cd (II) and As (III) metals removal. Equilibrium data agreed well for the biosorption of Cd (II) and As (III). The experimental data fitted very well with the Pseudo-second order kinetics model in both the cases. The FT-IR spectra of unloaded plant biomass and metal loaded biomass were obtained to understand the nature of possible interactions between the metal ions and functional groups of biosorbents. The FT-IR analysis revealed that the main functional groups involved in biosorption were carbonyl, amino, alcoholic, carboxyl and phenol. Regeneration of the biosorbent was carried out and it was observed that the biosorption capacity of the biosorbent decreases with consecutive cycles. The biosorption capacity was highest in the first cycle while least in the fourth regeneration cycle. Thus, it can be concluded that Citrus limetta peels can be used as cost-effective and environment-friendly alternative over commercial methods of treatment for the removal of heavy metals from contaminated water.
Open Access
Biosorption of heavy metals Cadmium(II) and Arsenic(III) from synthetic waste water solution using Punica granatum L.
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-05) Ritu Rani; Kasana, Virendra
In recent times, heavy metals, generally Cd(II) and As(III) has received a great deal of attention because of its high toxicity. The aim of present study was to examine the biosorptive capability of fruit peel of Punica granatum, collected from plains of Uttarakhand. The effective removal of heavy metals from aqueous wastes is among the most important issues for many industries. Fruit peel waste is abundantly available from the agricultural and food processing industry and has been studied in recent times as an adsorbent. Fruit peels biosorbents are characterized for their low cost, less expensive and high bioremoval capacity. Pomegranate peel is an important source of natural phenolic compounds. GC-MS showed that these biosorbents contains polysaccharides, proteins and lipids, and functional groups like carboxylic, hydroxylic, sulphate, and amino that act to bind metal ions. Pomegranate peels were used to remove Cd(II) and As(III) from synthetic wastewater. AAS results showed that the best adsorption for Cd(II) was obtained in contact time of 60 minutes and As(III) in 90 minutes at acidic pH and 45±5ºC temperature. The maximum removal of Cd(II) and As(III) at 25±5ºC and 45±5ºC temperature by P. granatum was recorded to be 35% and 69%, 52% and 73% respectively. As(III) was found to have more affinity to pomegranate peels. Langmuir, Freundlich and Temkin adsorption isotherm models were used to explain adsorption phenomenon of Cd(II) and As(III). The powder was regenerated and found to exhibit binding capacity upto four cycles as indicated by AAS. Adsorption kinetics data were modeled using the pseudo-first order, pseudo-second order and Elovich equations models. The results indicate that the secondorder model best describes adsorption kinetic data. The FT-IR analysis revealed that the main functional groups involved in biosorption were carboxyl, carbonyl, amino, alcoholic and phenol. Thus, it can be concluded that dried powder of pomegranate fruit peels, a waste material, possess good potential as an adsorbent to remove toxic metal ions like Cd(II) and As(III) and therefore can be used in the treatment of contaminated wastewater for removal of toxic metals.
Open Access
Effect of humidity on conductivity of nanocomposite electrodes
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-06) Arya, Bhagwati; Zaidi, M.G.H.
A series of NHs were prepared through surfactant assisted dispersion polymerization of indole in presence of various concentrations of WC. For this purpose, concentration (%,w/w) of WC was ranged from 5.0 to 15.Graphite based electrodes were fabricated from NHs in presence of PVB over iron substrate (1 cm2) and investigated for their microstructure, stability under heat and humid environment. Molecular binding of electrode materials was investigated through FTIR spectra. With concentration of WC, a regular increase in electrical conductivity of electrodes was observed, that was compromised on humidity treatment beyond 6hr. Generally in humid environment the thermal stability and electrical conductivity of electrode were found increases but after 6h of humidity electrical conductivity shows decreasing order. Electrical conductivity of electrodes was investigated through four point probe method in presence of a nanovoltmeter and current source. Study reveals that humidity treatment has enhanced the thermal stability and electrical conductivity of NHs derived electrodes.
Open Access
Development of nanocomposite modified electrode for voltammetric estimation of cholesterol
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-05) Sharma, Shubham; Sameena Mehtab
Higher levels of cholesterol lead to life-threatening coronary heart diseases, cerebral thrombosis atherosclerosis etc. therefore monitoring in serum is one of the most important biochemical assay. In the present investigation, non-enzymatic electrochemical sensors was developed for the low level estimation of cholesterol. Polymer nanocomposites have proved to be an excellent transducer in electroanalytical sensing, due to their unique properties like, low cost, good electronic characteristics, rapid electrode kinetics, biocompatibility and environmental stability. The synthesis of polyindole by chemical oxidative polymerization in presence of tungsten carbide ranging from 5 to 15 (%, w/w) and iron (III) chloride as an oxidizing agent. polyindole tungsten carbide electrodes were fabricated and characterized through various spectral, electrical, thermal and electrochemical methods. Synthesized PIN/WC nanocomposites in presence of sulphonated polysulphone was used to modify the surface of stainless steel plate electrode that worked as working electrode in electrochemical studies. The surface morphology of nanocomposites was characterized by SEM. The electrochemical behavior and quantification of cholesterol was studied by cyclic voltammetry and square wave voltammetry in 1 M KOH electrolytic solution. The overall results reveals that developed PIN/WC/SSPE electrode has excellent performance for trace level cholesterol and can be further employed for cholesterol monitoring in blood serum samples.
Open Access
Studies of surface morphology and electrode conductivity of polyindole nanocomposite with temperature variation
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-06) Rita; Sameena Mehtab
A series of polyindole (PIn)/tungsten carbide (WC) with graphite (Gr) polymer nanocomposites (PNCs) electrodes were fabricated at different concentrations of WC (%, w/w) ranging from 5.0 to 15.0 over an iron plate. PNCs were characterized through various spectral, thermal and electrical methods. FT-IR spectra confirmed the formation of PNCs and SEM reveal the microstructure of surface of PNCs. Thermal haracterization revealed that thermal stability of PNCs increases with addition of WC. All PNCs show linear I/V characterization and their electrical conductivity increases with WC concentration and applied voltage. The control (PIn+Gr) shows lowest conductivity, whereas [III] indicate the highest conductivity in comparison to other PNCs. It was found that the conductivity of EM [III] increased with concentration of WC and maximum value obtained was 0.71 × 10-2 Scm-1 at 100 V. The effect of the baking temperature range 50-100°C and baking time range 6-12 hours on the conductivity of EM [III] was same. Conductivity also increases with baking time and baking temperature up to 6 hours and 50°C, then a gradual decreases in these parameters started. Present investigation reveals that the designed electrode can be utilize in electrochemical energy storage devices under optimize baking conditions.
Open Access
Voltammetric quantification of cholesterol over Polyindole Tungsten Carbide Modified Electrode
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-05) Joshi, Preeti; Sameena Mehtab
The determination of CHO levels in blood is highly important because of an alarming rise reported in the rate of disorders due to abnormal levels of blood CHO. CHO sensing material estimation based on WC and PIN co-polymerization technology was synthesised. SSE have been modified by electroactive film of PIN with varying the concentration of WC 5, 10 and 15% (%, w/w) and SPS was used as a binder. DPV was performed for the EC quantification of CHO and electrochemical stability was investigated through EIS and potentiodynamic polarization in KOH (1.0 M). DPV with scan rate 30 to 50 mV/s and potential range 0.15 to 0.65 V were studies to optimize the EC parameters. The LOD obtained for [I], [II] and [III] are 7.63 × 10-6 molL-1, 10.37 × 10-6 molL-1 and 1.23 × 10-6 molL-1 and LOQ are 23.13 × 10-6 molL-1, 31.42 × 10-6 molL-1 and 3.74 × 10-6 molL-1 respectively. It was found that the correlations between the CHO concentration and peak current were in linear relation with micro molar sensitivity. DPV and EIS data reveals that [III] imparts the best detection limit and stability as compared to the bare, [I] and [II]. Tafel data also exhibits the improved corrosion resistance of [III] than [I], [II] and SSE. The present investigation reveals a fast, sensitive and low cost WC/PIN nanocomposite modified EC sensor to detect CHO. The developed sensor can also be employed for the CHO estimation in biological systems.
Open Access
Phytochemical analysis and biological activity of Cotinus coggygria Scop. collected from Kumaun hills of Uttarakhand
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-05) Thapa, Payal; Om Prakash
The aim of present study was to analyze the chemical composition and to evaluate the biological activities of the essential oil of Cotinus coggygria Scop. and various extracts. The plant material was collected from Chanfi, Padampuri (Nainital), hills of Uttarakhand in the month of May, 2018. The extraction of essential oil from aerial parts of plant was done by hydrodistillation method using Clevenger apparatus. Extracts of leaves and branches were subjected for extraction by the process of cold percolation method in organic solvent having different polarity. The essential oil and extracts obtained were chemically analyzed by the combination of GC and GC-MS. The major compounds identified in the essential oil of C. coggygria were myrcene (39.5%) pinene (11.4%), -terpineol (8.5%), cymene (5.7%), sabinene (5%), spathulenol (2.7%), -pinene oxide (2.6%), globulol (2.4%) and caryophyllene (1.6%). However, cis-9cis-12-octadecadienoic acid(33.9%), -monolinolein (9.5%), myrcene (7.9%), pinene (6.5%), phenol (5.9%), margaric acid (5.1%), methyl 8,11,14-heptadecatrienoate (4.4%), sabinene (3.3%), aromadendrene (2.8%), curdione (2.6%), lignoceric acid (2.4%), isocaryophyllene (2.3%), levoglucosan 3TMS (2.3%) and asarone (1.2%) were some major compounds identified in different extracts. The DPPH radical scavenging activity of C. coggygria essential oil possess good (IC50=10.34±0.57μL) antioxidant activity. Methanol extract showed higher (IC50=35.08±0.02μg/mL) antioxidant potential followed by ethyl acetate extract (IC50=38.61±0.51μg/mL). The reducing power activity of C. coggygria essential showed good (RP50=14.21±0.07μL) reducing power activity. Ethyl acetate extract showed better reducing power (RP50=31.05±0.05μg/mL) followed by methanol extract RP50=42.53±0.21μg/mL). Metal chelating activity of C. coggygria essential oil showed good (IC50=12.59±0.02μL) antioxidant activity. Methanol extract showed moderate chelating power with IC50=26.24±0.73μg/mL in comparison to ethyl acetate extract having (IC50=35.03±0.03μg/mL). C. coggygria essential oil showed good IB50=12.33±0.28μL anti-inflammatory activity whereas methanol extract showed better (IB50=22.66±0.61μg/mL) anti-inflammatory activity followed by ethyl acetate extract (IB50=27.83±0.79μg/mL). The insect anti-feedant activity of C. coggygria oil against Spilosoma obliqua showed excellent activity in comparison to extracts. The sprout suppressant activity in C. coggygria essential oil against R. raphanistrumshowed maximum inhibition in seed germination along with root and shoot length inhibition in comparison to extracts. Based on these results it can be concluded that C. coggygria can act as a good source of natural anti-oxidant, anti-inflammatory, anti-feedant and a bio-herbicide after proper clinical and scientific research.
Open Access
Investigation on chemical analysis and biological activities of Hedychium spicatum Sm. grown at Pantnagar
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-05) Rawat, Avneesh; Om Prakash
The purpose of present research was to investigate the chemical composition and to identify the biological activities of the essential oil and oleoresins of H. spicatum Sm. The rhizomes of cultivated H. spicatum were collected from Tarai region of Pantnagar (270m), Uttarakhand in the month of July and August 2018. The fresh plant material was subsequently subjected to hydrodistillation using Clevenger apparatus in order to obtained essential oils. Oleoresins were extracted from shade dried plant parts by Soxhlet apparatus/cold percolation method by using organic solvents of different polarity. The essential oils and oleoresins so obtained were chemically analysed by combination of GC and GC-MS. The major compounds present in the rhizomes essential oil of H. spicatum were camphor (27.3%) followed by 1,8-cineol (12.2%), curdione (9.3%), isoborneol (7.1%), (+)-linalool (5.7%), germacrene D (4.5%), (-)-borneol (4.4%), khusimone (3.0%), camphene (4.8%) and (E, E)-germacrone (4.3%). While the major components present in polar column fraction of essential oil were camphor (30%), curdione (14.5%), 1,8-cineol (9.5%), isoborneol (8.3%), camphene (4.8%), khusimone (4.6%), (+)-linalool (4.5%), (-)-terpinen-4-ol (2.4%), camphene hydrate (2.3%) and -elemene (2.0%). Methanolic extract of dried rhizomes were found to be rich in coronarin E (13.30%), linderazulene (5.94%), (-)-copalol (5.42%), curcumenone (5.09%), curdione (10.20%), germacrone (3.64%), E-dinorlabdadienal (3.59%), (+) -curcumol (3.15%) and -sitosterol (3.04%) whereas the extract in ethyl acetate was dominated by (-)-curcumol (13.02%) as the major component followed by curzerene (10.39%), curdione (9.56%), isovelleral (9.69%), curcumenone (7.24%), and -elemenone (5.94%). The in-vitro antioxidant activity was performed in terms of reducing power, DPPH radical scavenging and metal chelating effect. The essential oil (RP50= RP50=24.84±0.31) possess highest reducing power compared to ascorbic acid (RP50=26.54±0.32). The essential oil obtained from the rhizomes of the plant displayed highest radical scavenging potential with the IC50 value of 44.15±0.09 by comparing with the synthetic antioxidant BHT. Essential oil, IC50=17.62±0.13 and polar column fraction from oil, IC50=16.32± 0.59 exhibited maximum metal chelating effect in comparison to standard chelating agent EDTA. The polar column fraction (IB50=18.35±0.60) also showed a strong in-vitro anti-inflammatory effect compared to the standard drug, diclofenac sodium. Essential oil and polar column fraction show maximum antifeedant activity of 92.89% and 92.79% at 250ppm concentration when treated against Spilosoma obliqua Walker. The polar column fraction of oil also showed excellent herbicidal activity at 150 and 200 ppm concentrations and completely inhibiting the seed germination and seedling growth of R. raphanistrum. Essential oil also inhibited the complete growth of seeds at 200ppm concentration. The marked effect of anticancer activity was recorded by MTT (3-(4, 5-dimethylthiasol2-yl)-2,5-diphenyltetrazolium bromide) bioassay which revealed the IC50 value of 22.345 μg/mL for essential oil against A431 cell lines and 0.445 μg/mL against MFC (Michigan Cancer Foundation-7) cell lines. The IC50 value for polar fraction was 20.49 μg/mL against A431 cell lines and 22.7 μg/mL against MCF cell lines. The results thus revealed that this important Zingiberaceous herb can be a good source of nutraceutical after proper clinical trials. (
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.

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