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ThesisItem Open Access Synthesis and evaluation of cobalt oxide nanoparticles, grapheme oxide and their nanocomposite as superoxide dismutase mimics(Punjab Agricultural University, Ludhiana, 2019) Vaishali; Manpreet KaurIn the present study, superoxide dismutase mimics activity of pristine and cetyl trimethyl ammonium bromide (CTAB) coated cobalt oxide nanoparticles (NPs) and their graphene oxide (GO) nanocomposite (NC) was compared. The NPs, GO and NCs were synthesized employing sol-gel precursor, modified Hummers method and sonication method respectively. The synthesized NPs, NC were characterized using various techniques viz. SEM, XRD, FT-IR spectroscopy, BET analysis and TEM. CTAB coated cobalt oxide NPs showing highest activity was used for synthesis of NC with GO. Co3O4-GO NC with 1:2 displayed maximum activities among the synthesized NC, pristine GO and Co3O4 NPs. Enzyme mimic activity was evaluated using Marklund and Marklund method. Optimum pH, temperature, substrate concentration, NPs dose were 8.0, 25°C, 10 mM, and 2 mg respectively. Contact time studies were carried out for 3 min using pyrogallol as substrate. Kinetics studies of syntheised NPs showing best activity were conducted using Michelis Menton eqaution. The calculated Km and Vmax value of the NC were 0.021 mM and 0.0884 μmol sec-1 respectively. Thus NC can be further explored for replacing dismutase for varied applications.ThesisItem Open Access Chemistry and biological activities of banana (Musa sapientum) peel extract(Punjab Agricultural University, Ludhiana, 2019) Rashmi; Kaushal, SoniaThe present investigation deals with chemistry and biological activities of banana (Musa sapientum) peel extract. Banana peel extracts were prepared by Soxhlet extraction method using petroleum ether, dichloromethane, ethyl acetate, ethanol and methanol as solvents. GCMS analysis of methanolic extract showed the presence of 5-Hydroxymethylfurfural (24.78 %) as major compound. Methanol extract was subjected to column chromatography to isolate 5-hydroxymethylfurfural (5-HMF). It was chemically transformed into two derivatives viz. [5- (3-Nitrophenyliminomethyl)furan-2-yl]methanol and 5-Hydroxymethylfurfuralidene - acetophenone. 5-HMF and transformed compounds were identified by FT-IR and 1H-NMR studies. Mineral analysis of peel powder revealed the presence of K, Ca, P, Mg, Fe, B etc. Proximate analysis of peel powder showed the presence of (%) moisture (23.34), ash (13.62), crude fat (3.67), crude protein (8.14), crude fibre (22.21) and total soluble sugar (12.50) content. Phytochemical analysis revealed the presence of phenols, tannins, steroids and terpenoids in various extracts. The total phenolic content of various extracts ranged from 17.82 to 35.82 mg GAE/g of extracts. The peel extracts, 5-HMF and its derivatives were tested for their antibacterial potential against Klebsiella sp. and Pseudomonas aeruginosa using disc plate method, antifungal potential against Fusarium oxysporum by agar well diffusion method and antioxidant potential by DPPH and NO assay. Among all the treatments, maximum antibacterial potential was exhibited by methanol extract whereas ethyl acetate extract possessed maximum antifungal potential and 5- Hydroxymethylfurfuralideneacetophenone exhibited maximum antioxidant potential.ThesisItem Open Access Synthesis and evaluation of magnetized nanocomposites of rice husk silica and magnesium ferrite nanoparticles as adsorbent for Pb(II) ions(Punjab Agricultural University, Ludhiana, 2019) Tiwari, Shruti; Manpreet KaurThis study evaluates the adsorptive efficiency of MgFe2O4 and SiO2 nanocomposites (NCs) for removal of Pb(II) ions from aqueous solutions. Rice husk was used as source of mesoporous SiO2 nanoparticles (NPs) and MgFe2O4 NPs were synthesized via sol-gel method. Core-shell reversal of the NCs was achieved via surfactant assisted sonication method for MgFe2O4@SiO2 and direct precipitation method for SiO2@MgFe2O4 NCs. The fabricated adsorbents were characterized by employing XRD, FTIR, TEM, SEM EDS, BET and VSM analytical tools. SiO2@MgFe2O4 NCs displayed higher BET surface area and adsorption ability than MgFe2O4@SiO2 NCs. VSM results ensured the magnetic nature of MgFe2O4 NPs and the synthesized NCs. Physicochemical parameters like adsorbent dose, contact time, pH were evaluated for the detoxification of the spiked water samples using batch technique. The optimum pH was 6.0 and the adsorption obeyed pseudo-second order kinetics. Thermodynamic studies revealed the endothermic and spontaneous nature of the adsorption process for all the nanoadsorbents. The Langmuir and Freundlich isotherms fitted better than D-R and Temkin isotherms with qmax values in the range 26.67-48.08 mgg-1 which fully supported the adsorption affinity trend i.e. MgFe2O4 > SiO2@MgFe2O4 > MgFe2O4@SiO2 > SiO2. Adsorptive efficiency of SiO2@MgFe2O4 NC was comparable with MgFe2O4 NPs. It can be further modified to enhance its adsorptive potential.ThesisItem Open Access Synthesis of surface modified silver sulfide nanoparticles as antifungal agents(Punjab Agricultural University, Ludhiana, 2019) Sethi, Garima; AnjaliNanoparticles have great potential in the fields of biomedicine, building materials, environmental protection, antibacterial and antifungal agents. Silver sulfide nanoparticles (Ag2S NPs) have been synthesized for their applications in various fields including photoconductors, photovoltaic cells, solar selective coatings and infrared detectors, but have less reporting as bio-compatible material or in in vitro or in vivo applications. Silver sulfide has been hypothesized as less toxic form in nature as metal nanoparticles of soft nature get their ultimate fate by sulfidation as their natural pathway of detoxification. In this study we synthesized silver sulfide nanoforms by approaching sonochemical method. Various sulfide ion sources and silver nitrate were used as initial components for the synthesis of silver sulfide nanoparticles (Ag2S NPs). All the synthesized samples were tested for their preliminary in vitro antifungal activity against Ustilago hordei, Uromyces viciafabia, Fusarium moniliforme and Bipolaris oryzae . Ag2S-4 NPs synthesized from sodium sulfide showed better antifungal potential in comparsion to silver nanoparticles (Ag NPs) and commercially used standard fungicides. The Ag2S-4 NPs sample was further coated with chitosan to get chitosan decorated silver sulfide nanoparticles to evaluate the antifungal potential of this conjugate in comparison to Ag2S NPs.ThesisItem Open Access Synthesis of indole derivatives and their antimicrobial activity(Punjab Agricultural University, Ludhiana, 2019) Jain, Palak; Utreja, DivyaA novel series of eleven C-3 and N-1 substituted oxoacetamide indole derivatives were synthesized by reacting with various aromatic amines and alkyl halides. These compounds were characterized by using 1HNMR, 1HNMR-D2O, 13CNMR and IR spectroscopy. In vitro, antimicrobial studies of resultant compounds were carried out by using disc plate method against two bacterial strains Pseudomonas aeruginosa and Pseudomonas oryzihabitans. All the tested compounds showed vital efficiency as antimicrobial agents against both the bacterial strains. The results revealed that synthesized indole derivative 2-(1-(3-bromopropyl)-1H-indol-3-yl)-N-(2-nitrophenyl)-2-oxoacetamide displayed best antimicrobial activity as compared to all other synthesized compounds.ThesisItem Open Access Synthesis and antifungal potential of 1,2,4- triazolyldithiocarbamato-silver nano hybrids(Punjab Agricultural University, Ludhiana, 2019) Varinder Kumar; AnjaliSodium salts of 1,2,4-triazolyldithiocarbamates were synthesized by reacting 1,2,4-triazole/4- amino-1,2,4-triazole with carbon disulfide under strong alkaline medium (sodium hydroxide), which were further used for preparing other 1,2,4-triazolyldithiocarbamates(TDTC- (1-10)), in excellent yield. Screening of synthesized compounds for antifungal potential indicated TDTC-4 having maximum mycocidal potential against Fusarium moniliforme, Bipolaris oryzae, Phytopathora infestans and Rhizoctonia solani better than the standard fungicides (Tilt, Zineb and Mancozeb). Silver nanoparticles were synthesized by reduction methodology using silver nitrate and sodium borohydride. The physiotopological properties did not allow the significant encapsulation of compound TDTC-4 on AgNPs. So, they were not taken for continued studies on antifungal potential.ThesisItem Open Access Synthesis of N-substituted-3(4-hydroxy-3-methoxy phenyl) acrylamide derivatives and their fungitoxicity(Punjab Agricultural University, Ludhiana, 2019) Gupta, Divya; Sharma, SunitaFerulic acid is an abundant phenolic phytochemical component, possessing many medicinal properties. Derivatives of ferulic acid, show stronger physiological activities and are less toxic than ferulic acid. The amide moiety is one of the most significant chemical building block found in nature. An efficient synthetic pathway for synthesizing derivatives of N-substituted-3(4-hydroxy-3-methoxyphenyl) acrylamide was evolved in the present study, and eight compounds (I-VIII) were synthesized in appreciable yields. The synthetic route involved acetylation of hydroxyl group of ferulic acid followed by amidation with 4-aminobenzoic acid. The resultant compound hence formed, 4-(3-(4-acetoxy-3-methoxyphenyl)acrylamido)benzoic acid (II), was then condensed with different heterocyclic amines, viz., 4-aminophenazone, substituted amino-pyridines and substituted amino-1,2,4-triazoles, in the presence of base (triethylamine), to obtain amides (III-VIII), which were identified and characterized on the basis of physical data and spectroscopic studies (UV, IR and 1H NMR), respectively. All the synthesized compounds along with ferulic acid were screened in vitro for their fungitoxicity against three phytopathogenic fungi of maize, viz Rhizoctonia solani, Macrophomina phaseolina and Fusarium moniliforme using poisoned food technique. Comprehensive perusal of the results proclaimed that introduction of 3-amino-1,2,4-triazole moiety in the acetyl ferulic acid and 4-aminobenzoic acid-containing structure (compound VIII) increased their fungitoxic effect against mycelial extension of R. solani (ED50 = 38 μg ml-1), as well as F. moniliforme (ED50 = 840 μg ml-1). However, the degree of inhibition of compound (VIII) was lesser in the event of F. moniliforme than that of R. solani. On the contrary, incorporation of 4-aminobenzoic acid moiety in acetyl ferulic acid (compound II), elevated its fungitoxicity in case of M. phaseolina (ED50 = 86 μg ml-1). Moreover, no synthesized compound was more potent than the Carbendazim 50WP standard against all the three tested fungi.ThesisItem Open Access Comparative studies on the synthesis of benzylidene derivatives of syringaldehyde and their fungicidal activity(Punjab Agricultural University, Ludhiana, 2019) Parmjeet Kaur; Sharma, SunitaSyringaldehyde is a phenolic aldehyde having significant importance in the field of synthetic chemistry. Schiff bases are the compounds containing azomethine group and formed by the condensation of a primary amine with carbonyl compound. Benzylidene derivatives of syringaldehyde (I-VII) were synthesized by reacting its equimolar quantities with different substituted amines using glacial acetic acid. These were synthesized by conventional, microwave irradiation, sonication, water based and grindstone methods. Microwave irradiation method was best among all methods as it gave highest yield in least time. Progress of reaction was monitored by thin layer chromatography. All synthesized compounds were identified and characterized by physical (color, state, melting point and yield) and spectroscopic techniques (UV, IR and 1H NMR) respectively. The synthesized compounds were tested at different concentrations 1000, 500, 250, 100 and 50 μg ml-1 for in vitro fungicidal activity against Fusarium moniliforme, Macrophomina phaseolina and Rhizoctonia solani fungi of maize using Carbendazim 50 WP as standard. Compound (II) which contains triazole moiety showed highest percent inhibition at 1000 μg ml-1 against M. Phaseolina. Compound (V) having hydroxyl group on benzene ring was found to be most effective against F. moniliforme and R. solani. All compounds differed significantly at all concentrations and exhibited less inhibition than Carbendazim 50 WP.ThesisItem Restricted Synthesis of surface capped metal oxide nanoparticles as antifungal agents against phytopathogenic fungi(Punjab Agricultural University, Ludhiana, 2019) Harmandeep Singh; AnjaliThe development in the field of nanoscience and nanotechnology has opened new avenues for large number of technological applications in the field of biological science. In the present research, metal oxide nanoparticles were synthesized by using thermal treatment. MgO NPs were synthesized by using magnesium nitrate and sodium hydroxide as precursors. ZnO NPs were synthesized using zinc acetate dihydrate and sodium hydroxide. Prepared samples, were characterized by Transmission Electron Microscopy (TEM), UV-Visible Spectroscopy (UV-Vis), X-ray Diffraction (XRD), Atomic force microscopy (AFM), Zeta potential, Dynamic light scattering (DLS) and Scanning Electron Microscopy-Energy dispersive spectroscopy (SEM-EDS). MgO NPs were coated with Ethyl 5-(4- methoxyphenyl)-7-methyl-(1,2,4)triazolo[1,5-α]pyrimidine-6-carboxylate (TP) (TP: MgO- NPs) and 4-methyl-N-(1H-1,2,4-triazol-3-yl)benzenesulfonamide (TS) (TS: MgO-NPs). Similarly, ZnO NPs were coated with (TP) (TP: ZnO-NPs) and (TS: ZnO-NPs). Prepared samples were screened for their in vitro antifungal potential against various phytopathogenic fungi viz. Ustilago hordei, Uromyces viciafabia, Fusarium moniliforme and Bipolaris oryzae.