School Of Basic And Applied Sciences

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Author: search.filters.author.Kaur, ManpreetHas files: Yes

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    Nutrient enhancement of chickpea grown with plant growth promoting bacteria in local soil of Bathinda, Northwestern India
    (Springer, 2019) Dogra, Nitin; Yadav, Radheshyam; Kaur, Manpreet; Adhikary, Arindam; Kumar, Sanjeev; Ramakrishna, Wusirika
    Plant growth promoting bacteria (PGPB) enhance crop productivity as part of green technology to reduce the use of chemical fertilizers. They also have the capability to enhance macro- and micronutrient content of plants. In the present study, PGPB isolates belonging to Pseudomonas citronellis (PC), Pseudomonas sp. RA6, Serratia sp. S2, Serratia marcescens CDP13, and Frateuria aurantia (Symbion-K) were tested on two chickpea varieties, PBG1 and PBG5 grown for 30 days in local soil from Bathinda region in Northwestern India. PC and CDP13 were found to be better chickpea growth stimulators compared to the commercial Symbion-K based on shoot length and biomass. Most PGPB enhanced macro- and micronutrients in shoots to varying degrees compared to the control. PBG5 gave better response compared to PBG1 with reference to plant growth attributes and enhancement of the macronutrients, calcium, nitrogen and phosphorus and micronutrients, boron, copper, iron, and zinc. PBG5 is a high yielding variety with better resistance compared to PBG1. Overall, PGPB isolated from the local soil and PGPB from other parts of India were shown to be useful for enhancement of nutrient content and plant growth.
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    C‐N and N‐N bond formation via Reductive Cyclization: Progress in Cadogan /Cadogan‐Sundberg Reaction.
    (wiley, 2018) Kaur, Manpreet; Kumar, Raj Kumar
    Cadogan/Cadogan‐Sundberg cyclization reaction has been reported as one of the most efficient routes for the synthesis of a wide variety of N‐heterocycles from the easily accessible starting materials such as o‐nitrobiaryls or o‐nitroarenes, o‐nitrostyrenes by treating with tetravalent phosphorus compounds (trialkyl or triaryl phosphines or trialkyl phosphites). The reaction has been successfully employed in Carbon‐Carbon as well as Carbon‐Nitrogen bond formation for the scaffolds like carbazole, indoles, coumarins, and indazoles. To the best of authors’ knowledge, the present review is the first compilation of the literature from almost two decades (2000 to present) on Cadogan/Cadogan‐Sundberg cyclization reaction, its scope, mechanistic aspects, and limitations.
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    Assessment of antioxidant potential of phytochemicals in human glioblastoma (U-87 MG) cells
    (Central University of Punjab, 2014) Kaur, Manpreet; Mantha, Anil K.
    Imbalance between production of reactive oxygen/nitrogen species (ROS/RNS) leads to oxidative stress and has been well documented for mitochondrial dysfunction, a prime cause towards pathogenesis of neurological diseases and cancer. Glioblastoma Multiforme (GBM) is a highly aggressive, invasive and primary brain tumor which shows resistance to chemotherapy and radiotherapy. Superoxide dismutase (SOD) is an antioxidant enzyme that scavenges the production of superoxide radicals and dismutases into H?O? which is further converted into H?O and O? by catalase (CAT) enzyme. Apurinic/Apyrimidinic endonuclease (APE1) is a central enzyme of base excision repair (BER) pathway with two important functions; DNA repair and redox regulation of transcription factors (TFs) responsible for cell survival. In this study, it was seen that oxidative stress induced by endogenously found oxidants H?O? and glucose oxidase (GO) enhanced the activities of both CuZn-SOD and MnSOD in U-87 MG cells. In addition, CuZn-SOD levels were found to be increased in H?O?-induced oxidative stress and MnSOD levels were found to be increased in both H?O? and GO- induced oxidative stress. Further, pretreatment with phytochemicals Curcumin and Quercetin modulated the activities and expression of both forms of SOD studied. The BER-pathway enzyme, APE1 level was found to be decreased in mitochondria of oxidative stress induced U-87 MG cells by H?O? and GO, and in contrast APE1 level was found to be increased in cytosol, which indicates that oxidative stress affects the expression level and sub-cellular localization of APE1. Taken together, these results indicate that in GBM it is more likely that activated SOD a key player of antioxidant system and APE1 a key player in BER-pathway might be facilitating cancer cells to survive in oxidative stress environment.
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    Toward an Understanding of Structural Insights of Xanthine and Aldehyde Oxidases: An Overview of their Inhibitors and Role in Various Diseases
    (John Wiley and Sons Inc., 2018) Kumar, Raj; Joshi, Gaurav; Kler, Harveen; Kalra, Sourav; Kaur, Manpreet; Arya, Ramandeep
    Almost all drug molecules become the substrates for oxidoreductase enzymes, get metabolized into more hydrophilic products and eliminated from the body. These metabolites sometime may be more potent, active, inactive, or toxic in nature compared to parent molecule. Xanthine oxidoreductase and aldehyde oxidase belong to molybdenum containing family and are well characterized for their structures and functions, in particular to their ability to oxidize/hydroxylate the xenobiotics. Their upregulated clinical levels causing oxidative stress are associated with pathways either directly involved in the progression of diseases, gout, or indirectly with the succession of other diseases such as diabetes, cancer, etc. Herein, we have put forth a comprehensive review on the xanthine and aldehyde oxidases pertaining to their structures, functions, pathophysiological role, and a comparative analysis of structural insights of xanthine and aldehyde oxidases? binding domains with endogenous ligands or inhibitors. Though both the enzymes are molybdenum containing and are likely to share some common pathways and interact with inhibitors in a similar manner but we have focused on structural prerequisites for inhibitor specificity to both the enzymes keeping in view of the existing X-ray structures. This review also provides futuristic implications in the design of inhibitors derived from inorganic complexes or small organic molecules considering the spatial features and structural insights of both the enzymes. ? 2017 Wiley Periodicals, Inc.
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    An in vitro study ascertaining the role of H2O2 and glucose oxidase in modulation of antioxidant potential and cancer cell survival mechanisms in glioblastoma U-87 MG cells
    (Springer New York LLC, 2017) Cholia, Ravi P.; Kumari, Sanju; Kumar, Saurabh; Kaur, Manpreet; Kaur, Manbir; Kumar, Raj; Dhiman, Monisha; Mantha, Anil K.
    Glial cells protect themselves from the elevated reactive oxygen species (ROS) via developing unusual mechanisms to maintain the genomic stability, and reprogramming of the cellular antioxidant system to cope with the adverse effects. In the present study non-cytotoxic dose of oxidants, H2O2 (100??M) and GO (10??U/ml) was used to induce moderate oxidative stress via generating ROS in human glioblastoma cell line U-87 MG cells, which showed a marked increase in the antioxidant capacity as studied by measuring the modulation in expression levels and activities of superoxide dismutase (SOD1 and SOD2) and catalase (CAT) enzymes, and the GSH content. However, pretreatment (3?h) of Curcumin and Quercetin (10??M) followed by the treatment of oxidants enhanced the cell survival, and the levels/activities of the antioxidants studied. Oxidative stress also resulted in an increase in the nitrite levels in the culture supernatants, and further analysis by immunocytochemistry showed an increase in iNOS expression. In addition, phytochemical pretreatment decreased the nitrite level in the culture supernatants of oxidatively stressed U-87 MG cells. Elevated ROS also increased the expression of COX-2 and APE1 enzymes and pretreatment of Curcumin and Quercetin decreased COX-2 expression and increased APE1 expression in the oxidatively stressed U-87 MG cells. The immunocytochemistry also indicates for APE1 enhanced stress-dependent subcellular localization to the nuclear compartment, which advocates for enhanced DNA repair and redox functions of APE1 towards survival of U-87 MG cells. It can be concluded that intracellular oxidants activate the key enzymes involved in antioxidant mechanisms, NO-dependent survival mechanisms, and also in the DNA repair pathways for glial cell survival in oxidative-stress micro-environment. ? 2017, Springer Science+Business Media, LLC.