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ThesisItem Open Access Microbial and electrical characterization of polyindole/hemoglobin composites(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-10) Rawat, Shristi; Mehtab, SameenaCPs and conjugate polymers composites have many important applications as supercapacitors, sensing materials, fuel cells, solar cells, batteries etc. In this direction, in present studies we developed WEs by the coating of PIN/Hb. Three types of PIN/Hb composites C-I, C-II and C-III with varying concentrations (100 mg, 200 mg and 300 mg) of Hb were mixed with selected and optimized binder (SPS) and filler (Gr). A homogenous slurry of all components were prepared in NMP solvent and manually spread over SS to develop coated WEs. The WEs obtained were further used for electrical characterization over Keithley four-probe DC conductivity meter. At variable voltage, I-V graph of PIN and its composites obtained were in linear relation that reflects Ohmic behaviour of composites. Conductivity data of examined WEs reveals that, at RT (25oC±1), all composites exhibits higher conductivity than PIN and it further increases with increase in concentration of Hb in composites at all examined voltages (1, 10 and 100 V). It was found that conductivities for all WEs were constant at 1 and 10 V and maximum at 100 V. Further C-III reflected highest value of conductivity 0.1 × 10-2 Scm-1 at 100 V. Conductivity examinations of WEs at variable temperature ranging from 25-125oC showed maximum conductivity (0.16 × 10-2 Scm-1) of C-III at 75oC. It was found that the conductivity of WEs increased up to 75oC and then it decreased and became constant after 100oC. WEs were baked at temperature range of 50-100oC in oven and their conductivities were measured over the time duration of 3-9 hr. The highest conductivities for all WEs were obtained at 50oC with baking over 3 hr, while C-III showed maximum conductivity (0.51 × 10-2 Scm-1) at similar baking condition. Baking examinations at 50oC over time, reflected that conductivities increases up to 3 hr, then there was a gradual decrease till 6 hr, after that it remained constant up to 9 hr for all WEs. Similar baking trends of conductivities were observed at 100oC for same time parameters. These changes in conductivity of WEs with temperature and baking over time, might be due to change in surface morphology, cracking and delamination of coating materials over SS at higher temperatures and extended time period. As per literature PIN was found to exhibit antifungal activities, but in our studies C-I, C-II and C-III, did not display any antifungal activities against three tested fungus Penicillium chrysogenum, Aspergillus niger, Trichoderma asperellum. Even it was observed that there is enhancement in the growth of fungus with C-I, C-II and C-III exposure that may be due to carbon source of PIN and Fe in Hb from composites that act as fungal growth promoters. Present investigation provides a simplified way of optimization and fabrication of WEs with enhanced electrical conductivities at variable temperature range and baking conditions and data reveals that C- III can be used in electrochemical energy storage devices.ThesisItem Open Access Studies on physical and antimicrobial characteristics of polypyrrole/hemoglobin composites(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-10) Holaria, Pooja; Mehtab, SameenaA series of electrodes were prepared for PPY (PPy) and it’s composites with Hb (PHC-1, PHC-2, PHC-3). Electrodes were fabricated using two different binder and solvent combination over stainless steel surface. PVB and THF combination showed best surface morphology. Conductivity for electrodes was measured at room temperature using four probe method, PHC-3 shows the best conductivity result at room temperature. For optimization of electrode different PVB concentration (8 mg, 15 mg, 35 mg, 75 mg) were used in PHC-3. 35 mg PVB in PHC-3 shows the best result for conductivity at room temperature, therefore working electrodes for PPy, PHC-1, PHC-2 and PHC-3 were prepared with 35 mg binder concentration. All prepared electrodes were further tested for physical characterization. Electrodes were kept under humid environment for 8 hrs and were found to be morphologically stable. With increase in amount of Hb in PPy, increase in conductance was observed, PHC-3 shows the best results for conductance. For different PVB concentration conductance increases up to 35 mg PVB in PHC-3 and then decreases with further increase in binder amount. A sharp rise in σDC of WEs was observed at 100 V in each case that attributes to their behaviour as intrinsic semiconductors. All PHCs show linear I/V characterization and their electrical conductivity increases with Hb concentration and applied voltage. Effect of binder on I-V also shows linear variation and conductivity increase with increase in PVB up to 35 mg and then decrease with further increase in PVB amount. However, a sharp rise in σDC of WEs was observed at 100 V that attributes to their behaviour as intrinsic semiconductor. PHCs of concentration 1 mg/mL, 1.5mg/mL and 2 mg/mL were tested against 3 fungi A. niger, P. chrysogenum and T. asperellum, composites show no inhibition capability at tested concentration.ThesisItem Open Access Seasonal variation in chemical composition and biological activities of essential oils from leaves of Skimmia anquetilia N.P. Taylor and Airy Shaw(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-10) Arya, Stuti; Om PrakashThe aim of the current investigation was to analyze the chemical composition and biological activities of the essential oil from the aerial part of Skimmia anquetilia (N.P Taylor and Airy Shaw). The plant material was collected was from Harinagar, District Nainital, Dhari, Uttarakhand India, situated at an altitude of 2100m. during the month of September 2020 and January 2021. The essential oil were extracted by hydro-distillation method using Clevenger type apparatus and were designated as SKREO (Skimmia anquetilia rainy essential oil) and SKWEO (Skimmia anquetilia rainy essential oil) rescpectively. The yield of SKREO & SKWEO were 0.70% and 0.60% respectively by v/w. The essential oils were analysed for phytochemical composition and biological activity viz, antioxidant, anti-inflammatory, antidiabetic, antifeedant and nematicidal activity. GC and GC/MS analysis of SKREO & SKWEO was done for qualitative and quantitative analysis viz: linalyl acetate (15.8% -17.6%), linalool (13.2%- 13.9%), geijeren (11.6%- 11.7%), thujene (11.3%- 11.1%), α-terpineol (6.1%- 6.1%), geranyl acetate (5.0%- 5.1%), α–terpinyl acetate (3.3%- 3.1), myrcene (3.0%- 3.1%), geraniol (2.6%- 1.9%), α-pinene (2.1%- 2.2%), transβ- ocimene (2.1%- 2.3%), cis-β-ocimene (2.0%- 2.2%), neryl acetate (2.3%- 2.4%), sabinene (1.4%-1.5%), α- elemol (1.8%- 1.3%), epi- α -elemol (1.9%- 1.6%), 3- farnesyl acetate (1.7%- 2.4%) respectively. In terms of quality many constituents identified in SKREO were minor in SKWEO and viceversa. The in vitro antioxidant activity of SKREO & SKWEO was conducted by means of DPPH radical scavenging, H2O2 radical scavenging and metal chelating activity taking BHT and Na2 EDTA as the antioxidant standard respectively. SKREO showed higher DPPH radical scavenging potential (IC50=36.91±0.397) than SKWEO (IC50=41.31±0.561). In H2O2 radical scavenging assay SKREO showed great activity while in metal chelating activity SKREO showed better antioxidant potential than SKWEO. The in vitro anti-inflammatory activity was conducted using protein denaturation assay taking standard dichlofenac sodium as an anti-inflammatory drug. SKWEO (IC50=43.77±0.346) showed strong in vitro anti-inflammatory activity than SKREO (IC50=47.83±0.104). The antidiabetic activity of SKREO & SKWEO was performed using α-amylase inhibition assay by taking standard antidiabetic drug acarbose. SKREO (IC50=38.210±.030) showed better antidiabetic activity than that of SKWEO (IC50=52.06± 0.045 μl/mL). Antifeedant activity of both SKREO & SKWEO was performed against Spodoptera litura insect and the observation showed both SKREO (74.06%) and SKWEO (91.67 %) were observed to exhibited potent antifeeding activity at dose dependent manner. The nematicidal mobility activity of SKREO & SKWEO was performed against Meloidogyne incognita. The results revealed that SKREO was found to be most effective with 48.66% and 47.41% in SKWEO. SKREO gave minimum inhibition of egg hatching with 6.43% as compared to SKWEO 11.27%. The shrub S.anquetilia can be good source of phytochemicals like linalyl acetate, linalool, geijeren, thujene and herbal source for antioxidant, antiinflammatory, antidiabetic, antifeedant and nematicidal activity after proper clinical trials, besides its academic importance.ThesisItem Open Access Thermal and antimicrobial characterization of lac(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Bhoj, Megha; Zaidi, M.G.H.Present study demonstrates the thermal and antimicrobial characterizations of Lac along with spectra and DC conductivity. Study reveals intact thermal stability of Lac irrespective to rate of heating. Lac was thermally degraded in single step at 10oCmin-1 with TG onset at 300oC.This was left with 8.28% residue. Degradation of Lac was concluded TG end set at 500oC leaving 8.83% residue. Thermo gram of Lac decomposed @ 20oCmin-1 thermo gram reveals not much significant shift in TG onset and TG end set temperatures. This attributes thermally stable nature of Lac irrespective to increasing heat of degradation. FT-IR spectra of Lac reveals the presence of characteristic functionalities supported with literature. σDC of Lac pellets was studied at three different voltages in the range of 1 to 100V at room temperature. σDC measurements revels increase in conductivity of Lac with voltage is 2.5 × 10-2 Scm-1. Lac did not exhibit any zone of inhibition against three test fungi : Aspergillus niger, Trichoderma asperellum, Penicillium chrysogenum at various concentrations using both the disc and well diffusion methods.ThesisItem Open Access Seasonal variation in chemical composition and biological activities of essential oils from Artemisia annua L.(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-10) Malhotra, Akanksha; Om PrakashThe objectives of the present research study were to investigate the seasonal variation in phytochemical analysis and biological activites of Artemisia annua essential oils. The plants were collected from Tarai region of Uttarakhand, Pantnagar in the month of September, 2020 and January 2021 respectively .The essential oils of fresh aerial part of the collected plant materials were extracted by hydrodistillation using Clevenger apparatus and were studied by GC/MS for its phytochemical study and various biological activities. The essential oils isolated in rainy and winter season were designated as AAREO & AAWEO respectively. The phytochemical analysis of AAREO revealed the identification of 75 constituents which contributed 91.7% of the total essential oil. The major components of AAREO were camphor (14.1%) followed by germacrene –D (9.0%), trans-β-caryophyllene (8.7%), eucalyptol (4.2%), cis-cadin-4en-7-ol (3.9%), isoborneol (3.2%), p-cymene (2.9%) etc. Similarly, in AAWEO 59 constituents were identified which contributed 94.1% of the total essential oil. The major components of AAWEO were camphor (17.9%) followed by eucalyptol (14.6%), (E,E)-2,6-dimethyl-3,5,7-octatrien-2-ol (6.3%), (5E)-2,6-dimethyl-1,5,7-octatrien-3-ol (5.2%), artemisia alcohol (3.5%), isoborneol (3.2%), caryophyllene oxide (3.1%), artemisia ketone (2.5%) etc besides other minor and trace constituents. Both AAREO & AAWEO showed qualitative and quantitative differences in their phytochemical makeup. Both AAREO and AAWEO exhibited dose dependent in-vitro anti-oxidant activity, evaluated by , DPPH scavenging, metal chelating assay and H2O2 radical scavenging as indicated by different IC50 values. IC50 =77.87±0.528 to IC50=45.588±0.334 μl/mL for DPPH radical scavenging activity similarly IC50 =51.40±0.158 to IC50=49.50±0.234 for metal chelating activity and IC50 = 44.83±1.304 to IC50 =34.79±0.419 for H2O2 radical scavenging activity with respect to various standards like, BHT and Na2EDTA respectively. With respect to diclofenac sodium, the standard anti-inflammatory drug both AAREO and AAWEO exhibited anti-inflammatory activity with IC50= AAWEO (IC50=66.90±0.040) > AAREO (IC50=76.55±0.218) μl/mL respectively. Similarly, significant anti-diabetic activity was observed in both AAREO and AAWEO with IC50= 74.26±3.706μl/mL to IC50= 47.45±0.195μl/mL, respectively compared to standard acarbose (IC50= 38.21±0.03μl/mL). Both AAREO and AAWEO were observed to exhibit strong anti-feedant activity respectively against Spodoptera litura (90.85% & 87.92%) .Like wise AAREO & AAWEO were subjected to nematicidal activity against root knot nematode, Meloidogyne incognita. It was observed that AAREO exhibited more mortality over AAWEO at different concentration ( 1-5 μl/mL) , where as in the case of egg inhibition process AAWEO was found to be more effective (5.38% egg hatching) than AAREO (11.41% egg hatching)at a concentration of 10 μl/mL respectively. Based on observations of above mentioned study, it can be inferred that Artemisia annua can be a good natural resource of camphor and 1,8 cineole and the essential oils can be good source of antioxidant, anti-inflammatory, anti-diabetic, anti-feedant and nematicidal activities after proper clinical trials.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 Thymus linearis Benth.: Study on essential oil composition with seasonal variation and biological activities(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Kabdal, Tanuja; Ravendra KumarThe present study was aimed to analyse the phytochemical nature and to evaluate the biological activities of the essential oil of Thymus linearis Benth. collected in two different seasons. The plant material was collected from the Kumaun region of Uttarakhand in rainy season (TLRO) and winter season (TLWO). The oil from the plant material was extracted by hydro distillation using Clevenger type of apparatus and the yield obtained was 1.3% and 1% respectively. The phytochemical analysis of the oils was done by GC and GC/MS. The major component in both the oils was thymol with varying percent composition, i.e., 31.9% in TLRO and 35.7% in TLWO. The other major components in TLRO were γ-terpinene (12.5%) and p-cymene (10.6%) while in TLWO the other major components were p-cymene (12.9%) and borneol (6.1%). The different biological activities of essential oils were performed using standard protocols. In in vitro antiinflammatory activity performed using denaturation of egg albumin protein, TLWO (IC50=26.55±0.03) showed more potent effect. The antioxidant activity as evaluated using three different methods which were DPPH radical scavenging activity, H2O2 radical scavenging activity and metal chelating activity and tested good activity for TLWO compared to TLRO. The antidiabetic activity of oils was analyzed using α-amylase inhibition assay. TLWO showed better inhibition of the enzyme showing its more antidiabetic potential with IC50 value 32.27±0.05. Insect antifeedant activity was performed using leaf dip method against the test insect Spodoptera litura. Significant activity was shown by both the oils but more potent activity was shown by TLWO. The nematicidal activity tested against Meloidogyne incognita demonstrated higher mortality in case of TLWO than TLRO. TLWO also showed more inhibition of hatching of the eggs of Meloidogyne incognita.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.
