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ThesisItem Restricted Characterization and evaluation of rice straw lignin phenolics on pollen germination in pumpkin(Punjab Agricultural University, Ludhiana, 2021) Jasleen Kaur; Ramandeep KaurRice straw is one of the most abundant, renewable, cost-effective and non-edible agricultural feedstocks. Its burning has led to air pollution, loss of soil fertility and nutrient depletion, therefore valorization of rice straw is important. Straw was found to be chemically composed of 24% hemicellulose, 41% cellulose, 9% lignin, 20% extractives and 6% ash (silica). Lignin was extracted using dilute acid pretreatment (1% H2SO4) followed by alkaline hydrolysis using NaOH. FT-IR, 1H and 13C NMR were used for structural characterization of the lignin obtained from rice straw. The ethyl acetate extract of acid solubilized lignin was found to contain p-coumaric acid, ferulic acid and caffeic acid as the major phenolic acids which were isolated using preparative thin layer chromatography. The phenolic acids were characterized using elemental analyses, FT-IR, 1H and 13C NMR spectroscopy. Amides of p-coumaric acid, ferulic acid and caffeic acid were synthesized by their reaction with propyl and butyl amines using microwave irradiation and analysed using spectral studies. Phenolic acids and their amides were evaluated for their effect on pollen germination and tube growth in pumpkin. It was concluded that at 5 ppm concentration, germination percentage and pollen tube growth of p-coumaric acid, caffeic acid and their amides was enhanced than the control. These results could be utilised in increasing pollen tube length of Cucurbita moschata while making interspecific cross between C. moschata and C. pepo in order to transfer the hull-less and disease and virus resistant character of C. moschata to C. pepo.ThesisItem Open Access Synthesis and application of biopolymer hydrogels for seed germination in Calendula(Punjab Agricultural University, Ludhiana, 2021) Sharma, Rupali; Ramandeep KaurRice straw is renewable, non-edible, cost effective and abundantly available feedstock, burning of which leads to emission of hazardous gases, therefore its utilisation is important to reduce extensive atmospheric pollution. The percent composition of rice straw was determined by detergent system method and was found to contain 20.00, 41.00, 24.00, 9.00 and 6.00% extractives, cellulose, hemicellulose, lignin and acid-insoluble ash (silica), respectively. Lignin was extracted by using the dilute acid pretreatment method of rice straw, in which rice straw was treated with 1% H₂SO₄ followed by its alkaline hydrolysis. Lignin was structurally characterized by FT-IR, ¹H and ¹³C NMR spectra. Lignin hydrogels were synthesized using lignin as raw material, poly vinyl alcohol as a matrix template and epichlorohydrin as a crosslinker followed by their characterization using FT-IR and SEM analysis. Different concentrations of lignin hydrogels (0.2%, 0.5%, 0.8% and 1%) were synthesized out of which 0.5% lignin hydrogels proved to be the most efficient due to their high swelling ratio i.e. 130.34 and high reswelling capacity. The dye adsorption capacity of lignin hydrogels came out to be more than that of neat PVA hydrogels. This was followed by evaluation of lignin hydrogels as culture media for seed germination of Calendula. Further, root length, shoot length, root:shoot length, seed vigour index, germination percentage and germination index were noted. It was concluded that 0.5% and 0.8% lignin hydrogels have proved to be efficient as culture media for seed germination of flowering plant Calendula.ThesisItem Restricted Synthesis and derivatization of substituted 3,5-dimethoxy-4-hydroxy benzaldehydes and their biological activities(Punjab Agricultural University, Ludhiana, 2021) Sahni, Tanvi; Sharma, SunitaNaturally occurring phenolic aldehyde 3,5-dimethoxy-4-hydroxybenzaldehyde (syringaldehyde) was derivatized to synthesize compounds like Schiff Bases (I-IX), β-lactams (X-XI), azo derivatives (XII-XV), hydrazones of azo derivatives (XVI-XXVII), hydrazones (XXVIII-XXXI), thiosemicarbazones (XXXII- XXXIII), ,β-unsaturated compounds (XXXIV-XXXVIII) and esters (XXXIX-XLIX). Characterization of synthesized compounds was done using UV-visible, FT-IR, 1H and 13C NMR. All the synthesized compounds were evaluated for antioxidant potential i.e. DPPH, FRAP and Phosphomolybdate assay), microbial potential against Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Klebsiella sp. and Enterobacter sp. and fungicidal potential against four pathogenic fungi of maize against Rhizoctonia solani, Dreschlera maydis, Fusarium verticillioides and Macrophomina phaseolina. In the DPPH assay, syringaldehyde and compounds (VI, VII, XXXVIII and XXXIX) were more effective than standard BHT while none of the compound was more effective than standard ascorbic acid. In FRAP assay, compounds (VII, X, XI, XVIII, XX, XXI, XXII, XXIII, XXIV, XXV, XXVI, XXVII) were effective than ascorbic acid and BHT standards while none of the compound was more effective than ascorbic acid in terms of phosphomolybdate assay. Compounds (VIII, X, XI, XV, XXI, XXIV and XXXIX) were more effective than ampicillin against B. subtilis. Compounds (I, II, III, VI, VIII, IX, X, XI, XII, XIII, XIV, XV, XVIII, XXI, XXII, XXIII, XXIV, XXV, XXVII and XXXIX) showed greater zone of inhibition than ampicillin against P. aeruginosa. Microbial potential at par with ampicillin against E.coli was showed by compounds (VIII, XI, XXI and XXII). Four compounds (XV, XXI, XXII and XXVI) were more effective than ampicillin against Enterobacter sp. while none of compound was found more effective than ampicillin against Klebsiella sp. Antifungal potential of Compound (VI) was found at par with carbendazim 50 WP against R. solani. Mycelial growth of D. maydis was inhibited by fourteen compounds more than carbendazim 50 WP but less than Mancozeb 75 WP. None of the compound was effective than carbendazim 50 WP against F. verticillioides and M. phaseolina.ThesisItem Open Access Isolation and antifungal evaluation of bioactive compounds from Vinca rosea(Punjab Agricultural University, Ludhiana, 2021) Sharma, Parul; Ramandeep KaurVinca rosea is an evergreen plant belonging to family Apocynaceae possessing numerous medicinal properties. The present work deals with the extraction and chemical investigation of V. rosea leaves and flowers extracts, leaves essential oil and its potential as fungicide against two phytopathogenic wheat fungi i.e., Fusarium graminearum and Bipolaris sorokiniana. Leaves and flowers extracts were prepared using six different solvents. GC-MS analysis of the methanolic extract of leaves revealed tetradec-7-enal (19.61%), glycerol (17.58%) and palmitic acid (16.38%) as the major compounds whereas methanolic extract of flowers showed inositol (42.66%) as the major compound. Quantitative data revealed the presence of alkaloid in higher quantity in leaves. Vindoline, was isolated from the leaves of the plant and other major compounds were isolated by column chromatography from methanolic leaves and flowers extracts. Structures of isolated compounds were elucidated by FT-IR, 1HNMR, 13CNMR and Mass spectroscopic techniques. Fungitoxic activity of V. rosea leaves and flowers extracts, essential oil and isolated compounds was investigated by poisoned food technique at different concentrations (125-1000 µg/ml). Propiconazole (Tilt 25 EC) served as positive control. Methanol extract of leaves and flowers was found to be more effective in comparison to other extract. Among all the tested components, vindoline was observed to be the most active compound against F. graminearum (ED50 = 68 µg/ml) and B. sorokiniana (ED50 = 97 µg/ml). Further the activity was increased with increasing concentration but still less than the synthetic fungicides.ThesisItem Restricted Chemical characterization and insecticidal activity of leaves and flowers of Ageratum conyzoides(Punjab Agricultural University, Ludhiana, 2021) Gurdeep Kaur; Ramandeep KaurAgeratum conyzoides (Asteraceae) is an invasive herb widely distributed in tropical and subtropical parts of the world. The plant is widely studied due to its wide diversity in chemical composition. In the present investigation, the evaluation of insecticidal activity of leaves and flowers of methanol extract and its petroleum ether, chloroform and ethyl acetate fractions were studied against second and fourth instar larvae of Spodoptera litura. The compound βcaryophyllene was isolated from the methanol leaves extract by column chromatography. The larval mortality of both the instars was studied after exposure to various extract and compound at different concentrations (5, 10 and 15%) after regular interval of 24, 48 and 72 h of treatment. It was found that methanol flowers extract exhibited the highest larval mortality of 57.33±0.115% at 15% concentration after 72 h of treatment. Further it was observed that the fourth instar larvae were more susceptible than second instar larvae. Therefore, parameters like consumption index, growth index and morphological deformities were also studied for fourth instar larvae of S. litura. It was observed that the consumption index exhibited a direct relation with concentration and time whereas inverse relation was found with growth index. The lowest consumption index was found in β-caryophyllene (0.030±0.034 mg mg-1day-1) followed by methanol flowers (0.045±0.039 mg mg-1day-1) and methanol leaves (0.057±1.417 mg mg-1day-1) extract. Various morphological deformities in larval and pupal stages were observed. The adults emerged were reduced in size and exhibited wings deformities. Overall, β-caryophyllene exhibited a highest insecticidal activity and has the potential to be developed as botanical pesticide. These findings might have important implications for environment friendly control of pests by using botanical pesticides.ThesisItem Open Access Evaluation of synthesized ferrite nanocomposites with N-doped graphene and carbon microspheres for the removal of heavy metals and organic pollutants(Punjab Agricultural University, Ludhiana, 2021) Manmeet Kaur; Manpreet KaurMagnetic ferrites and their nanocomposites with nitrogen doped graphene oxide (N-GO) and hollow mesoporous silica have received immense interest as adsorbents and photocatalysts for water decontamination. This work reports facile strategy for the synthesis and evaluation of N-GO, MFe2O4 NPs (M= Mg, Ca), MFe2O4-NGO (M= Mg, Ca) and hollow mesoporousnanocomposites for the removal of Pb(II), Ni(II), As(III), CR dye and PNP from contaminated water.NCs of NGO with MFe2O4 NPs were prepared using ultra sonication method. For dual core shell nanocomposite, hollow mesoporous SiO2 core was synthesized using polyethylene glycol (PEG) and cetyltrimethyl ammonium bromide (CTAB) as cotemplates. Synthesized SiO2 was used as template over which MgFe2O4 NPs were loaded using sodium dodecyl sulphate (SDS) as a surfactant to synthesize MgFe2O4@SiO2 core-shell nanocomposite. This nanocomposite was further loaded with N-GO in order to design NGO@MgFe2O4@SiO2 dual core nanocomposite by ultra sonication method. Structural, magnetic and surface properties of the nanocomposites were analyzed using various physicochemical techniques. The effectiveness of NPs and nanocomposites for the removal of Pb(II), Ni(II) and As(III) and photodegradation of CR and PNP was studied.MgFe2O4@SiO2 displayed maximum heavy metal removal whereas, NGO@MgFe2O4@SiO2 dual corenanocomposite exhibited maximum photocatalytic degradation for organic pollutants. The mechanism of adsorption and photocatalysis from spiked water was investigated by batch experiment studies.The adsorption data was best fitted into Langmuir adsorption isotherm and followed pseudo-second-order kinetic model.The degradation mechanism for CR and PNP was proposed on the basis of mass spectrometric analysis of products formed during photodegradation. Also, the comparative photocatalytic activity of spiked distilled water and contaminated water revealed reduction in photocatalysis of 17% and 22% in the contaminated water. The synthesis of NCs of MgFe2O4 NPs with doped carbon material and core-shell synthesis using SiO2 core provide new synthetic strategy for further modification of pristine ferrite NPs for future applications.ThesisItem Restricted Synthesis and fungicidal activity of 2-aminopyrimidine schiff bases(Punjab Agricultural University, Ludhiana, 2021) Amanpreet Kaur; Sharma, Sunita2-Aminopyrimidines represent an important class of bioactive molecules where its structural changes would lead to its versatile properties. N-Heterocyclic compound i.e. 2aminopyrimidine had wide range of applications in medicinal, material chemistry and agriculture as antifungal, antimicrobial and antibacterial agents. In the present study, a series of substituted N-benzylidine-2-aminopyrimidine compounds were synthesized by condensation reaction of 2-aminopyrimidine with substituted benzaldehydes (o-chloro, mhydroxybenzaldehyde, p-hydroxybenzaldehyde, 2,5-dimethoxybenzaldehyde, pdimethylaminobenzaldehye, syringaldehyde, o-phthaldehyde, isovanillin benzaldehyde, veratraldehyde and thiophene-2-carboxyaldehyde). The synthesised Schiff bases were characterized using UV, IR, 1H NMR and 13C spectral studies. The antifungal activity of all the synthesized Schiff bases was screened against Fusarium verticillioides, Macrophomina phaseolina, and Rhizoctonia solani using poisoned food technique. The Schiff base of pdimethylaminobenzaldehyde and 2-aminopyrimidine showed hundred percent inhibition against all the three fungi but less than carbendazim at 50 WP as its ED50 was less than all the synthesized Schiff bases. Thus, in future, this kind of pyrimidine derivatives may be used to generate better fungicides with improved fungicidal activities.ThesisItem Restricted Adsorption studies on magnesium ferrite-bentonite nanocomposite by linear and nonlinear modeling(Punjab Agricultural University, Ludhiana, 2021) Khushboo; Manpreet KaurThis study envisages the adsorption and photodegradation studies on magnesium ferrite (MgFe2O4)-bentonite nanocomposite by linear and nonlinear modeling, using Cd (II) and martius yellow as model pollutants. The accumulation of MgFe2O4 nanoparticles (NPs) on the bentonite was affirmed by XRD, FT-IR, TEM and SEM-EDS studies. The linear and nonlinear regression methods were employed to accurately predict the adsorption and photodegradation mechanisms. The statistical parameters were evaluated for determining the best-fitted model. Linear type-II Langmuir equation best represented the equilibrium data for Cd (II) ions and martius yellow, which indicated monolayered and physical adsorption. Nanocomposite showed the maximum adsorption capacities of 1073.3 mg g-1 and 789.6 mg g1 for Cd (II) and martius yellow, respectively. The linear pseudo-second-order (type-I) kinetic model gave best-fit for both the adsorption and photodegradation, which specified the interaction of the Cd (II) and martius yellow with two active sites of the adsorbent. The synergistic effect for martius yellow degradation was observed by Cd (II) adsorbed nanocomposite. Degradation pathway was predicted on the basis of quenching studies and GCMS analysis. Thermodynamic studies revealed the endothermic and spontaneous nature of adsorption process. The reusability studies of nanocomposite signified its effectiveness. The present studies demonstrated that among linear and nonlinear modeling, the former fitted well for both adsorption and kinetic studies.ThesisItem Restricted Profiling of Micronutrients and Heavy metals in Ocimum species of Punjab(Punjab Agricultural University, Ludhiana, 2021) Arora, Aayushi; Tandon, RituMedicinal plants are the foundation stones of Ayurveda and Siddha system of medicine as they help in curing a variety of ailments. Genus, Ocimum represents a major member of medicinal plants of family Lamiaceae. Ocimum, also known as Tulsi, is indigenous to the Indian continent and is highly revered for its medicinal uses. Scientific examinations of the medicinal plants w.r.t elemental analysis especially heavy metals are lacking to ensure development of their safe formulations. Such studies are needed to ensure the standardization and quality control of the developed products and approval for use in primary health care. This need has greatly emphasized on the development of analytical methods for their elemental analysis to produce reliable results and hence to guarantee the quality. In present study, ICP-MS method was validated for the simultaneous determination of essential micronutrients (Co, Ni, Se, Cu, Mn, Zn, Al and Fe) and toxic elements (Cr, As, Cd, Pb and Hg) in Ocimum leaves. The extraction of samples was performed by a microwave assisted digestion with HNO3 to stabilize these elements. The validated method fulfilled all the acceptance criteria (Correlation coefficient (R) ≥ 0.995, Recoveries ranging between 70-130 % and RSD ≤ 20 %) for the parameters: linearity, limit of detection/quantification, accuracy and precision at three levels of concentrations. LOQ for all the elements varied from 0.01160.55 µg/kg. Three Ocimum species (Ocimum kilimandscharicum, Ocimum basilicum and Ocimum sanctum) collected from two different locations (PAU, Ludhiana, Punjab and Fragrance and Flavour Development Centre, Kannuaj, Uttar Pradesh) were analyzed for their micronutrient and heavy metal contents by using the validated method on ICP-MS. Analytical results demonstrated that O. kilimandscharicum contained the highest levels of micronutrients especially Fe and Al than other two species. However, among various heavy metals, concentration of Cd (in O. basilicum) and Hg (in all Ocimum species) were found to be higher than their permissible limits of 0.3 and 1.0 mg/kg respectively. The validated method, thus, can be effectively used in laboratory for routine determination of these micronutrients (8) and heavy metals (5) in Ocimum species with acceptable analytical performance.
