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ThesisItem Restricted Diapause induction and post-diapause development in Sesamia inferens Walker(Punjab Agricultural University, Ludhiana, 2021) Manmeet Kaur; Aggarwal, NaveenThe investigations on diapause induction and post-diapause development in Pink stem borer, Sesamia inferens Walker larvae were conducted under laboratory conditions at varying temperature and photoperiodic combinations of 10±1 and 14±1oC (10:14 h LD), 25±1oC (12:12 h LD), 30±1 and 34±1oC (13:11 h LD). Diapause was observed at temperature and photoperiod combinations of 10±1 and 14±1oC (10:14 h LD) and no diapause induction was recorded at 25±1oC (12:12 h LD), 30±1 and 34±1oC (13:11 h LD). The larval period of S. inferens was longer (61.74 and 52.41 days) at 10±1 and 14±1oC. It was significantly shorter at 25±1oC (30.11 days), 30±1oC (24.87 days) and 34±1oC (23.89 days). The minimum larval survival (pupation) of 64.01 and 65.45 per cent was recorded at diapausing temperature. It was significantly more at 25±1oC (86.36 %), 30±1oC (81.32 %) and 34±1oC (71.86%), respectively. Pupal period was prolonged significantly to 12.64 : 14.12 and 10.52 : 12.04 days in males and females at diapasing temperatures, respectively. However, it was significantly less in non-diapausing populations exposed at 25±1, 30±1 and 34±1oC (5.85-8.09 days in males and 7.24-10.23 days in females), respectively. Overall, S. inferens had longer total development period of 81.2 : 82.68 and 69.75 : 71.23 days in males and females individuals at both diapausing temperatures. At 25±1, 30±1 and 34±1oC, it reduces significantly to 36.5044.04 days in males and 37.89-46.18 days in females individuals. The highest population loss of 62.48 and 60.15 per cent was recorded at 10±1 and 14±1oC (10:14 h LD). Whereas, at 25±1oC (12:12 h L:D), 30±1 and 34±1oC (13:11 h LD) loss of only 6.3, 26.13 and 42.01 per cent was recorded. Morphometric parameters of diapausing larvae revealed that it completely lacks cuticular pigmentation and had reduction in the body size (9.98-12.03 mm) and head capsule width (0.62-0.67 mm). The non-diapause larvae had 12.88-26.95 mm body size and 0.71-1.91 mm head capsule width. The pupal (male: 9.59-10.58 mm length and 1.65-1.92 mm breadth; female: 11.42-12.52 mm length and 2.36-2.69 mm breadth) and adult sizes (male: 10.10-11.04 mm length and 2.04-2.48 mm breadth; female: 13-14.41 mm length and 3.25-3.76 mm breadth) of diapause populations were smaller and adults emerged from these populations were darker in colour than nondiapausing (male: 11.66-12.57 mm length and 3.23-3.52 mm breadth; female: 14.95-15.55 mm length and 4.42-4.63 mm breadth of adults and for pupa male: 10.86-12.24 mm length and 2.64-3.21 mm breadth and female: 12.76-14.66 mm length and 3.28-4.02 mm breadth) populations. About 14.6 per cent (10±1oC) diapausing larvae exhibited additional 2 instars followed by 9.3 per cent of larvae (14±1oC). The diapause in S. inferens significantly reduces the percentage pupation (64.01-65.45) and weights of pupae (62.98-65.41 mg of male and 128.69-133.7 mg of female), ultimately lowering the weight (34.98-37.83 mg of male and 50.4-52.70 mg of female) and reproductive performance of adults. The results clearly indicate that a reduction in oviposition period, fecundity and egg viability in a diapausing population of S. inferens ultimately leads to a reduction in population growth parameters. Larvae of S. inferens undergo for some biochemical adaptations for its survival during the diapausing conditions. More amount of proteins (27.5659.81 mg/g b.wt.) and glycogen (23.82-30.26 mg/g b.wt.) were estimated at temperature exposure of 2530oC. Lipids (10.53-12.02 mg/g b.wt.), trehalose (19.95-22.89 mg/g b.wt.) and total soluble sugars (24.9129.76 mg/g b.wt.) were significantly high in diapausing conditions. In present studies, facultative diapause was observed at 10±1 and 14±1oC alongwith shortday exposure of (10:14 h LD), indicated that population might be surviving during December-January under North-Indian winter and even the lower surviving population is sufficient for its carryover.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 Open Access study of content and quality of disclosures regarding business responsibility and corporate governance(Punjab Agricultural University, Ludhiana, 2015) Manmeet Kaur; Kapur, SandeepThe present study was undertaken for analysing corporate governance(CG) and business responsibility report(BR) of index based(common in Nifty & sensex) companies and non-Index based (listed under indexes other than Nifty & Sensex) companies and to examine the perception of brokers and investors towards both these reports. Secondary Data in form of annual reports was collected for analysing reports. The study regarding perception of investors was conducted in Ludhiana where 20 Brokers and 100 investors were part of sample population. Their perception was tested on usefulness, adequacy in content. Results indicate there is significant difference between disclosures regarding shareholder committee, non-mandatory requirement ,which are part of CG, and principles and significant risk and goals of management, which are part of BR report of index-based and non-index based companies . Response of investors and brokers indicated that non-mandatory disclosure of Corporate governance report is of least use to them and share holder information and party transactions in their view are most useful disclosures of corporate governance report. Business responsibility report according to them contains all useful disclosures but negative consequences of operations on social, environmental and economic fronts disclosure of is most inadequate in terms of content and quality.ThesisItem Open Access Enzymatic debittering and aroma enhancement of kinnow juice(Punjab Agricultural University, Ludhiana, 2017) Manmeet Kaur; Sahota, Param PalThe processing of acidic fruits to beverages has encountered commercial restrictions due to development of delayed and inherent bitterness by limonoids and flavonoids. The present study has been undertaken with purified debittering enzymes; limonin dehydrogenase, naringinase and β-glucosidase to meet the consumer palatability of citrus juices. The limonin dehydrogenase enzyme has been purified to 1.14- fold with 33.98% recovery, 29.25 IU activity and 0.525 IU/mg specific activity resulted in 86.43% degradation of limonin in juice by catalyzing oxidation of limonin –A-ring lactone to the non-bitter 17dehydroxylimonoate. The debittering naringinase enzyme 24.8IU activity,0.442 IU/mg specific activity, purified to1.68 fold could reduce 57.93% naringin which is hydrolysed by the enzyme into non-bitter bioactive compound naringenin.. The flavour enhancing βglucosidase with activity 14.68 IU, specific activity 0.344 IU/mg purified to 1.18 fold resulted in the increase in glucose content upto 4.25µg/ml in kinnow juice. The debittered fermented low alcoholic naturally carbonated (LANC) beverage has been developed by optimizing the bioprocess conditions as TSS 13ºB, yeast inoculum @ 0.75%(v/v), incubation temperature 28±2ºC and time 36hrs.The physicochemical changes were recorded as TSS 13ºB, acidity 0.313%, naringin 181.13 ppm, limonin 4.73 ppm, glucose 1.3µg/ml, total sugars 42.97 µg/ml, ascorbic acid 34.22 mg/ml in fermented kinnow beverage after 25 days of storage at 4ºC. In kinnow juice, maximum reduction in bitter component limonin 87.34%, naringin 58.41% whereas increase in glucose upto 4.38 µg/ml, acidity 30.13% and total sugar content 42.97 µg/ml were observed. The nutraceuticals recorded in fermented kinnow beverage were flavonoids (mg/L)- gallic acid 0.075, caffeic acid 0.002, rutin 0.001, ferulic acid 0.001; Organic acids (mg/L) – oxalic acid 0.243,tartaric acid 3.698, mallic acid 0.018, citric acid 0.432; Fat soluble vitamins (mg/L)-Vitamin A (Retinol) 0.060, cholecalciferol (D3) 0.038, α-tocopherol (Vitamin E) 0.001, Vitamin K 0.018 ; water soluble vitamins (mg/L)thiamine 0.782, pyridoxine hydrochloride 0.040, pantothenic acid 0.002, riboflavin 0.001, biotin 0.011; Protein 6.42g/100g,Carbohydrate 40.95g/100g.ThesisItem Open Access Optimization, production and partial purification of βglucosidase from yeast using citrus peel(Punjab Agricultural University, Ludhiana, 2016) Manmeet Kaur; Sahota, Param PalThe enzyme β-glucosidase hydrolyzes cellobiose and short chain cello-oligosaccharides to glucose. The study was conducted to evaluate the production of enzyme β-glucosidase using economically viable substrate citrus fruit waste with optimized batch scale fermentation using Clavispora lusitaniae strains KF633446 and KP131848.1 as yeast inoculum. The process parameters optimized during study are: substrate concentration (117.9g/L lemon peel powder or 46.875 g/L lime) or 16.8 g/L banana peel powder, temperature (35°C) and pH (5) , inoculum concentration of 0.75% v/v, time period of 36 h and 30h using yeast strains KP131848.1 and KF633446 respectively. Use of citrus fruit waste as substrate for enzyme production has proved to be economical; the maximum enzyme activity 0.49 IU/ml with lemon peel, followed by lime (0.28 IU/ml) and banana peel (0.337 IU/ml). The enzyme activity (IU) of β-glucosidase after partial purification was found to be 18.52 IU. The partially purified β-glucosidase was highly stable at temperature 45°C and pH 5. The value of Km and Vmax was 1.25mM and 17.98 IU/ml respectively using pNPG (para-nitrophenyl-β-Dglucopyranoside) as substrate. The addition of enzyme @ 0.4 ml per 100 ml of juice resulted in increased reducing sugar content in sweet lime juice (58.42%), grapefruit juice (57.36%), lemon juice (55.26%) and kinnow juice (53.19%), with storage time period of 15 days. Sensory analysis on 9 point hedonic scale revealed maximum score of 8.4±0.2 for aroma and 7.85±0.25 for flavour of lemon juice. This study revealed the commercial utilization of peel as substrate for β-glucosidase production and wide applicability of β-glucosidase enzyme in aroma and flavor enhancement along with debittering properties of enzyme Naringinase and Limonin dehydrogenase.ThesisItem Open Access Chemistry and biological activity of flavonoids from zest and pith of kinnow peel(Punjab Agricultural University Ludhiana, 2016) Manmeet Kaur; Uppal, S.K.Different extracts from zest (flavedo, orange part) and pith (albedo, white part) of kinnow peel were prepared by three extraction procedures i.e. conventional, ultrasonic assisted extraction and soxhlet extraction methods using different solvents (hexane, benzene, isopropylalcohol, ethylacetate and acetone). Soxhlet extraction method was found to be the best method giving maximum total phenolic and flavonoid content for kinnow zest extracts in isopropylalcohol solvent with values 40.41 mg gallic acid equivalent (GAE) g-1 dry weight (DW) and 6.07 mg quercetin equivalent (QE) g-1 DW, respectively whereas the values were found to be 37.34 mg GAE g-1 DW and 5.08 mg QE g-1 DW, respectively in kinnow pith extracts. The yields of hesperidin isolated from zest and pith of kinnow peel were found to be 0.6 and 1.4%, respectively. Whereas, yields of naringin were found to be 0.032 and 0.05% from zest and pith of kinnow peel, respectively. Aglycone forms, methylated and acetylated derivatives of isolated compounds were prepared which were identified by melting point, TLC, FT-IR and 1HNMR data. All zest and pith extracts, isolated compounds, their aglycone forms and derivatives were investigated for their 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity using 3,5-di-tert-butyl-4-hydroxytoluene (BHT) as a standard and antibacterial activity by disc plate method against Bacillus aryabhattai, Acinetobacter sp. and Klebsiella sp. using tetracycline as standard. Among all the extracts, isopropylalcohol extract showed highest antioxidant and antibacterial activities, whereas among different isolated and synthesized compounds, aglycone forms were found to be more effective than isolated compounds.
