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ThesisItem Embargo Studies on micro nutrient status of rice varieties from farmer's fields of Punjab(Punjab Agricultural University, 2024) Vaishali; Dr. Ritu TandonRice (Oryza sativa L) being the staple food and main dietary source of trace elements, it plays a significant role in our diet. Rice varieties like Basmati and Parmal are widely consumed throughout the world and exported from India. Rice is rich in micronutrients and macronutrients. Micronutrient insufficiency is thought to be one of the main causes of the falling rice productivity trends. Rice crop is also reported to accumulate higher concentrations of toxic elements compared to other plants. The presence of heavy metals beyond permissible limits as per regulatory guidelines questions the safety of rice for consumption. Thus, this study highlights the importance of regularly monitoring the nutritional value and heavy metal content in different rice varieties to ensure its safe consumption, especially for people who are heavily reliant on rice as an essential food source. In present study, ICP-MS method was validated for the simultaneous determination of essential micronutrients (Mn, Fe, Ni, Zn, Cu, Co and Se) and heavy metals (Cr, As, Cd and Pb) in rice. The validated method fulfilled all the acceptance criteria (Correlation coefficient (R) ≥ 0.995, Recoveries ranging between 75-125 % and RSD ≤ 20 %) for the parameters: linearity, limit of detection/quantification, accuracy and precision at different levels of concentrations. Five different varieties of Rice (Punjab Basmati 1121, Punjab Basmati 1509, Punjab Basmati 1718, Parmal 126 and Parmal 121) were procured from different districts of Punjab (Hoshiarpur, Ludhiana, Patiala, Kapurthala, Bathinda, Amritsar, Jalandhar, Barnala and Gurdaspur) for micronutrient and heavy metal analysis by using the validated method on ICP-MS. Analytical results demonstrated that PB 1121 of Basmati variety of rice was found nutritionally rich for Fe, Ni, Cu and Zn. However, on the other hand basmati variety PB 1509 rich in Mn and Co whereas maximum Se content reported in PR 121. Similarly, all the rice varieties showed heavy metals content below the permissible limit of FSSAI. However, among other heavy metals i.e. overall Cr and Cd the content was reported to be the highest in PB 1121. Similarly, overall As and Pb contents were reported maximum in PB 1509 and PR 126. However all heavy metals were below the permissible limits of FSSAI. The validated method, thus, can be effectively used in laboratory for routine determination of these micronutrients and heavy metals in rice with acceptable analytical performance.ThesisItem Embargo Synthesis of paddy straw biopolymers based hydrogels and their use as media for plant growth(Punjab Agricultural University, 2022) Jaswinder Kaur; Mankoo, Ramandeep KaurPaddy straw consists of three important biopolymers i.e. cellulose, hemicellulose and lignin which can be used for the production of various highly demanded sustainable organic products. Microcrystalline cellulose (MCC) and lignin were extracted from paddy straw by using the dilute acid pre-treatment method followed by alkaline hydrolysis. Characterization of MCC was done by FT-IR, SEM images and lignin was characterized by FT-IR spectrum. Hydrogels were synthesized using MCC and lignin as the raw material, PVA as the matrix template, glutaraldehyde and Epichlorohydrin (ECH) as cross-linkers and characterized by FT-IR and SEM analysis. Hydrogels synthesized using glutaraldehyde crosslinker were observed to have less porosity and tight bonding network whereas ECH caused loose bonding between polymers and resulted in formation of large pores in hydrogels. Swelling ratio and reswelling capacity of hydrogels showed that lignin hydrogels performed best than all other hydrogels. Monocot (wheat) and dicot (moong bean) seeds were found to germinate on hydrogels which confirmed the tendency of hydrogels to modify the water retention properties of growing media. The physiological parameters i.e. total fresh and dry biomass, leaf area, seedling length of hydrogels on growth of germinated seedlings were observed under control and water stress conditions. All hydrogels performed well under stress conditions as compared to control. However, both lignin hydrogels performed best and gave highest growth under stress conditions. It was concluded that these biopolymer based hydrogels can be recommended for use as growth media ingredient in water deficient conditions.ThesisItem Embargo Synthesis of xylan and lignin based hydrogels and their use as growth media for rice (Oryza sativa)(Punjab Agricultural University, 2023) Japanpreet Kaur; Ramandeep KaurLignocellulosic biomass is the most economical and highly renewable crop residue in the world. It is nonedible plant material composed of cellulose, hemicellulose, and lignin and is present in environment as agriculture wastes which includes crop residues like paddy straw, wheat straw, etc. Lignin and xylan were extracted from paddy straw by pre-acid treatment which was followed by alkaline hydrolysis. Structural characterization of lignin and xylan was done by FT-IR and 1H-NMR spectra respectively. Different hydrogels were synthesized using lignin and xylan as the raw material, PVA as the matrix template, citric acid, and succinic acid as crosslinkers and were structurally characterized by FT-IR and SEM analysis. Hydrogels that were synthesized using citric acid as crosslinker were observed to cause loose bonding between polymers and resulted in formation of large pores in hydrogels whereas, hydrogels synthesized using succinic acid as crosslinker were observed to have less porosity and tight bonding network. The swelling ratio and reswelling capacity of hydrogels revealed that lignin hydrogels outperformed all other hydrogels. All the synthesized hydrogels were tested for their role as soil culture media ingredient for the germination of rice seedlings. Germination percentage was calculated on seventh day after sowing of rice seeds and it came out to be maximum in case of xylan/lignin hybrid citric acid crosslinked (LXC) hydrogels in both normal and stress conditions. Seedling length, total fresh weight, total dry weight, and leaf area were calculated after 30 days. All the hydrogels performed well in stress conditions as compared to normal conditions. Xylan/lignin hydrogel and lignin hydrogel synthesized using citric acid performed best and showed highest growth under stress conditions. It was concluded that the synthesized hydrogels could be used effectively as an ingredient of soil culture media owing to their tendency to absorb and retain water properly.ThesisItem Open Access Nanocomposite of magnesium ferrite and manganese oxide as polyphenol oxidase mimic and photocatalyst(Punjab Agricultural University, Ludhiana, 2022) Harmilan Kaur; Manpreet KaurArtificial enzymes have received immense interest due to their exceptional properties such as high stability and low-cost. Polyphenol oxidase enzyme mimic is well known for its contribution in the field of food industry, biosensors, medicine and water remediation. In the present study, Mn3O4 and MgFe2O4 nanoparticles and nanocomposites were synthesized by sol-gel and ultra-sonication methods. Their polyphenol oxidase (PPO) mimic activity was comparatively analyzed. The synthesized nanoparticles and nanocomposites were characterized by FT- IR, XRD, SEM-EDS, BET, and VSM. The results revealed that MgFe2O4@Mn3O4 possess unique catalytical features. XRD analysis of synthesized materials depicted crystalline nature. The PPO-like activity of synthesized NPs and NCs were analyzed using catechol and resorcinol as substrates. MgFe2O4@Mn3O4(1:2) were observed to be the best PPO mimic. Kinetic analysis under optimized conditions indicated higher binding affinity of nanocomposite as compared to pristine manganese oxide. MgFe2O4@Mn3O4 (2:1) showed to be best photocatalytic potential for catechol and resorcinol degradation in aqueous solution. The efficiency of degradation was put to the test in relation to the variation of several experimental parameters including: pH; nanoparticles dose and contact time These aforementioned parameters were optimized and examined for the influence that they exerted on the efficiency of degradation which involved the usage of the Box-Behnken design methodology. According to the ANOVA results that yielded a confidence level of 95 %, a high regression along with fitting values were obtained between the results of the experimental degradation of catechol and resorcinol and the predicted quadratic model. Thus, the present study indicated that a catalyst of MgFe2O4@Mn3O4 nanocomposite in different ratios have promising performance as photocatalyst and PPO-mimic for degradation of polyphenols.ThesisItem Embargo Synthesis of pyrimidinone derivatives and their antimicrobial activity(Punjab Agricultural University, 2023) Baljinder Kaur; Utreja, DivyaAn efficient protocol has been used for the synthesis of pyrimidinone derivatives via a onepot three-component condensation reaction of aryl aldehydes, malononitrile and barbituric acid in aqueous conditions using tetrabutylammonium hydrogen sulfate. A simple procedure, short reaction time, high yields (78–93 %), broader substrate scope, easy handling of the catalyst and simple work-up, i.e., non-column chromatographic separation of the desired products were attractive features of this process. The structures of synthesized derivatives (4aj) were confirmed by spectral analysis. The in vitro antimicrobial activity of the compounds was determined by the agar well diffusion method against Dickeya sp. (Gram-negative bacteria) and Streptomyces scabiei (Gram-positive bacteria). The synthesized compounds exhibited zone of inhibition at 10.67 ± 0.33, 9.50 ± 0.29 and 10.75 ± 0.14 mm in diameter for (4f), (4g) and (4j) respectively against Dickeya sp., compared to Gentamicin as standard (zone of inhibition at 19.17 ± 0.22 mm). The compounds were found to be potent towards the antioxidant activity. Using H2O2 scavenging assay, the derivatives (4g), (4j), (4i) and (4f) emerged to display promising antioxidant activities with inhibition percentages at 82.01 ± 0.28, 81.57 ± 0.34, 80.97 ± 0.19 and 76.97 ± 0.29 respectively, similar to the ascorbic acid and gallic acid (percent inhibition of 80.46 ± 0.32 and 79.51 ± 0.10, respectively) used as reference standards.ThesisItem Embargo Synthesis of thymol functionalized chemosensor and evaluation of its cytotoxicity to plant growth promoting rhizobacteria(Punjab Agricultural University, 2023) Ramneet Kaur; Gaba, JyotiA chemosensor (TPC) based on thymol was afforded by reaction of thymol and piperidine in methanol. The structure elucidation of TPC was done by UV-Vis, H-NMR, "C-NMR and FT-IR analysis. The absorption spectrum of TPC showed a band at 277 nm. The presence of Cu and Pb ions induced increase in the absorption intensity at 277 nm by 2-fold and 1.5- fold, respectively. Although, no alteration was observed in the UV-Visible spectra with the addition of other metal ions. The binding constant for both TPC-Cu and TPC-Pb was calculated as 1.55 >x 10° M and 1.47 x 10° M, respectively. The deduced limit of detection (LOD) and limit of quantification (LOQ) for Cu was 623.64 and 1889.85 uM, respectively. For Pb ions, LOD and LOQ was calculated as 676.70 and 2050.60 M, respectively. The binding stoichiometry was estimated as 1:1 by Job's plot method of continuous variation for both TPC-Cu and TPC-Pb* complex. TPC was also checked for reusability with EDTA, which was found effective for upto two cycles. The synthesized probe was further used for determination of concentration of Cu and Pb ions in spiked tap water samples and percent recovery were observed in range of 80.l to 81.0 % and 80.1 to 81.9 % for Cu and Pb ions, respectively. The cytotoxic study was also conducted which inferred that the compound TPC was non-cytotoxic against tested plant growth promoting rhizobacteria (PGPR) i.e. Rhizobium sp., Pseudomonas sp., and Azospirillum sp. at all the tested concentrations.ThesisItem Embargo Synthesis and evaluation of various of metal salicylates nano formulations against pathogenic fungi of rice(Punjab Agricultural University, 2022) Gandhi, Garima; UrvashiFive 2-oxobenzoatometal complexes viz. tetraaquo(2-oxobenzoato)zinc(II) dihydrate (1), sodium diaquobis(2-oxobenzoato)zincate(II) (2), sodium tris(2-oxobenzoato)zincate(II) (3), diaquo(2-oxobenzoato)copper(II) dihydrate (4) and sodium bis(2-oxobenzoato)cuprate(II) (5) were synthesized using a standard methodology having different molar ratios of metal and 2oxobenzoato ligand (salicylate ligand). They were further nanoformulated via. sonication and laser disintegration technique (blue laser). The in vitro antifungal evaluation revealed more profound results of laser disintegrated samples for inhibiting the fungal menace of two seed borne fungal pathogens of rice viz. F. fujikuroi and F. verticillioides. Sodium bis(2oxobenzoato)cuprate(II) (l-CuSA2) was the most effective in inhibiting the mycelium growth of both the test fungi i.e. F. fujikuroi and F. verticillioides, with ED90 values of 2347.17 + 0.28 μg/ml and 2373.41 + 0.47 μg/ml, respectively. Nanopriming of most infested rice seeds (PUSA 1509) with l-CuSA2 at 2500 μg/ml showed the best seed health and quality parameters and is accounted as the best nanoformulated complex which have opened the doors for further elaborative study for its utilization as seed nanopriming agent in agrosystems to replace Carbendazim (banned fungicide) for seed treatment.ThesisItem Restricted Chemistry and antioxidant potential of Tinospora cordifolia extracts and its bioactive compound(s)(Punjab Agricultural University, 2022) Poonamdeep Kaur; UrvashiThe present investigation deals with chemistry and antioxidant potential of Tinospora cordifolia extracts and its bioactive compound(s). The mineral analysis of the stem powdered showed the presence of potassium in the highest concentration whereas cadmium in the lowest concentration. The methanol extract of stem was prepared using Soxhlet apparatus and partitioned into polar and non-polar fractions using dichloromethane, chloroform and hexane as solvent. Qualitative analysis of phytochemicals affirmed the presence of phenols, flavonoids, saponins, alkaloids, tannins, terpenoids, steroids and cardiac glycosides in methanol extract. The total phenolic, flavonoid and alkaloid content of methanol extract was found to be 2.90±0.36mg GAE g-1, 3.79±0.48mg QE g-1 and 0.09379±0.45 mg B g-1, respectively. The major compound berberine was isolated from the chloroform fraction of T. cordifolia using column chromatography and the structure of compound was elucidated on the basis of spectroscopy analysis. Antioxidant potential was carried out using five different in vitro models involving 2, 2-diphenyl-1-picrylhydrazyl (DPPH) , hydroxyl (OH), nitric oxide (NO), superoxide (O2) radicals scavenging methods and ferric reducing antioxidant power assay (FRAP) at various concentrations (0.02-0.1 mg ml-1). The antioxidant activity increased with increase in concentration. Methanol extract was found to be most active as compared to other fractions. The antioxidant activity of methanol extract was comparable of berberine. Hence, methanol extract and berberine showed good potential as a source of natural antioxidants.ThesisItem Restricted Degradation, adsorption and leaching behaviour of triafamone and ethoxysulfuron and their effect on soil enzymes(Punjab Agricultural University, 2023) Rajandeep Kaur; Pervinder KaurField trials were carried out to compare the degradation of triafamone and ethoxysulfuron in soils of direct seeded (DSR) and transplanted rice (TPR) fields. Half-lives of triafamone ranged from 13.02 to 20.93 and 12.09 to 14.67 days under DSR and TPR conditions, respectively while for ethoxysulfuron half-lives ranged from 11.71 to 15.64 and 9.90 to 12.19 days. Among both the herbicides, triafamone was more persistent in the soil. Metabolite M1 and M2 appeared at 3 and 7 DAA of herbicide and persisted up to 21 and 15 days after application (DAA) of herbicide in DSR and TPR, respectively while E3 appeared at 21 DAA of herbicide and persisted up to 90 and 60 DAA of herbicide in DSR and TPR, respectively. The residues of herbicide at harvest at below the detectable limit (<0.008 µg g-1). Triafamone and ethoxysulfuron had a transitory harmful effect on soil biochemical and microbiological parameters depending herbicide dose. Triafamone and ethoxysulfuron has highest leachability in loamy sand followed by sandy loam and clay loam. Among both the herbicides, ethoxysulfuron was more mobile and leachability increased with increase in rainfall. The adsorption data fitted well in Freundlich equation with KF 1.819±0.07 to 3.319±0.074 and 1.064±0.050 to 2.330±0.020 µg1-1/ng-1ml1/n for triafamone and ethoxysulfuron, respectively. Adsorption increased with increase in OM and clay content of soil. Hysteresis ranged from 0.003 to 0.017 in studied soils indicating that triafamone and ethoxysulfuron was difficult to desorb due to its irreversible binding with soils.
