Botany - Research Publications

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    Monostroma: the Jeweled Seaweed for Future Cultivation methods, Ecophysiology, Phylogeography and Molecular Systematics
    (Lambert Academic Publishing, 2011) Bast, Felix
    This thesis aims at providing a comprehensive picture of the reproductive physiology, growth, phylogeography, and phylogenetics of M. latissimum-nitidum complex in Southern Japan. A review on agronomy and utilization of seaweeds is provided as Chapter 2 to present a comprehensive overview of the seaweed biology and applications. Seasonality in the growth and occurrence of Monostroma sp. at three environmentally distinct habitats along Tosa Bay, Kochi Prefecture, Japan is explored and results of correlation analyses between environmental conditions and thallus size are presented in Chapter 3. Also investigated in the same chapter is the homology of nuclear encoded rDNA Internal Transcribed Spacer (ITS) sequences between naturally occurring and commercially cultivated populations. Findings of the culture studies sought to identify the species naturally occurring at the study sites are also summarized in Chapter 2. In the course of research, I observed that thalli of the naturally occurring populations of M. latissimum, changes its color during maturation, as reported elsewhere in the literature. Further to that observation, a thorough cytological investigation on the gametangial ontogeny of naturally occurring M. latissimum is presented in Chapter 4 and possible taxonomic implications of this finding are discussed. Once the thalli of M. latissimum release gametes, which mode of syngamy do they have? Is sex of the progenies environmentally determined? These are some of the questions being investigated in Chapter 5. Reported in the Chapter 6 is a serendipitous discovery of an asexually reproducing ecotype of M. latissimum in the marginal populations at low-saline habitat. Findings of the culture studies to complete its life cycle are presented. Molecular studies to investigate homogeneity of nrDNA ITS sequences between the two ecot ypes (i.e., sexual vs asexual) are also investigated in the same chapter. Results of phylogenetic analyses of the newly generated ITS sequence of M. latissimum with that of the related monostromatic green algal taxa retrieved from GenBank are also presented in Chapter 6 to understand relative taxonomical position of this species in the class Ulvophyceae. Chapter 7 is an investigation on the morphologic and genetic homogeneity of natural and cultivated populations of the two closely related species M. latissimum and M. nitidum along the Southern Japanese coast where the warm-water Kuroshio Current influences throughout the year. Combined phylogeographical analysis of nuclear encoded first internal transcribed spacer (ITS1) sequences and rDNA 18s gene are presented in addition to the comparison of morphological traits, to understand if they belong to the same taxa. In the final experimental chapter, Chapter 8, taxonomic hypothesis for Monostromataceae were tested and the systematic position of this family is explored using multi-local phylogeny. Relationships of this family with over 40 Ulvophycean genera were investigated and phylogeny reconstruction was conducted using five independent genetic markers; viz., nrDNA ITS1, nrDNA ITS2, nrDNA 5.8S, nrDNA 18S and cpDNA rbcL. Chapter 9 summarizes and discusses the results of this thesis, places them in a regional context and discusses avenues of future work.
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    Seaweeds: Ancestors of land plants with rich diversity
    (Springer India, 2014) Bast, Felix
    Seaweeds are taxonomically diverse group of marine plants from which the land plants diverged over fifty crore years ago. Traditionally having been classified based on plant color as green, brown and red, modern molecular systematic evidences suggest that these plants are extraordinarily diverse. A number of seaweeds are edible and have been projected as a future food source. Seaweeds are also important to humanity in a number of ways, including as a source of medicines, food supplements, industrial chemicals, and as a potential candidate for biofuel research and CCS (carbon capture and sequestration). This article introduces the readers to the fascinating world of marine biology in general and seaweeds in particular, with an emphasis on Indian flora. ? 2014 Indian Academy of Sciences.
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    Pyramiding of tea Dihydroflavonol reductase and Anthocyanidin reductase increases flavan-3-ols and improves protective ability under stress conditions in tobacco
    (Springer Verlag, 2017) Kumar, Vinay; Yadav, Sudesh Kumar
    Tea (Camellia sinensis) is one of the richest sources of flavan-3-ols, an important class of flavonoids. The expression level of gene-encoded key regulatory enzymes of flavan-3-ol/anthocyanin biosynthetic pathway, dihydroflavonol 4-reductase (DFR) and anthocyanidin reductase (ANR), has been highly correlated with the flavan-3-ol contents and antioxidant activity in tea plant. In the present study, pyramiding of CsDFR and CsANR in tobacco was achieved. However, single transgenic tobacco overexpressing either CsDFR or CsANR was documented earlier. In continuation, pyramided transgenic lines were evaluated for the possible, either same or beyond, effect on flavan-3-ol accumulation and protective ability against biotic and abiotic stresses. The pyramided transgenic lines showed early flowering and improved seed yield. The transcript levels of flavan-3-ol/anthocyanin biosynthetic pathway and related genes in pyramided transgenic lines were upregulated as compared to control tobacco plants. The accumulations of flavan-3-ols were also found to be higher in pyramided transgenic lines than control tobacco plants. In contrast, anthocyanin content was observed to be decreased in pyramided transgenic lines, while DPPH activity was higher in pyramided transgenic lines. In pyramided transgenic lines, strong protective ability against feeding by Spodoptera litura was documented. The seeds of pyramided transgenic lines were also found to have better germination rate under aluminum toxicity as compared to control tobacco plants. Interestingly, the synergistic effect of these two selected genes are not beyond from transgenic lines expressing either CsDFR and CsANR alone as published earlier in terms of flavan-3-ols accumulation. However, the unique flower color and better seed germination rate are some interestingly comparable differences that were reported in pyramided lines in relation to individual transgenic plants. In conclusion, the present results reveal an interesting dynamic between CsDFR and CsANR in modulating flavan-3-ol/anthocyanin levels and functional analysis of stacked CsDFR and CsANR transgenic tobacco lines. ? 2017, Springer-Verlag GmbH Germany.
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    Identifying the preferred interaction mode of naringin with gold nanoparticles through experimental, DFT and TDDFT techniques: Insights into their sensing and biological applications
    (Royal Society of Chemistry, 2016) Singh, Baljinder; Rani, Monika; Singh, Janpreet; Moudgil, Lovika; Sharma, Prateek; Kumar, Sanjeev; Saini, G.S.S.; Tripathi, S.K.; Singh, Gurinder; Kaura, Aman
    In this work, the binding behaviour of naringin-a flavonoid with AuNPs is explained by combining experimental and theoretical approaches. We have systematically analysed the effect of temperature and concentration of naringin and gold (Au) in the formation of naringin stabilized Au nanoparticles (N-AuNPs). The interaction of naringin with gold nanoparticles (AuNPs) is investigated by various techniques such as UV-visible spectroscopy, TEM, FT-IR, XRD and gel electrophoresis. These studies indicate that naringin acts as a reducing and stabilizing agent. Further, we have modelled the two side chains of naringin with the functional groups [C10H7O2] and [C6H5O]-, and identified the lowest energy configurations of these groups with AuNPs with the help of density functional theory (DFT). The [C10H7O2]-Au13 has higher binding energy than [C6H5O]--Au13 and it is attributed to delocalized molecular orbitals in [C10H7O2], hence higher charge transfer to the Au13 cluster. On the basis of the resulting structures, we examine the optical properties using time-dependent density functional theory (TDDFT). We observe significant changes in the optical spectra of the representative structures of side chains with the AuNPs. The peak in the spectra of the Vis region of [C10H7O2]-Au13 undergoes a shift towards lower wavelength in comparison to [C6H5O]--Au13. Natural transition orbitals (NTOs) of hole and particle states of the [C10H7O2]-Au13 conjugate system are localized on [C10H7O2] and Au13, respectively, whereas for the [C6H5O]--Au13 both hole and particle states are localized on the Au13 cluster. These N-AuNPs show their applicability as a sensor for detecting aluminium ions (Al3+) in aqueous solution. These NPs are also found to be biocompatible with normal red blood cells and MDAMB-231 breast carcinoma cell lines, as evaluated from hemolysis and cytotoxicity assays. Thus, naringin offers non-toxic and bio friendly N-AuNPs, which are considered to be the best vehicle for drug release and other possible biomedical and sensing applications. ? 2016 The Royal Society of Chemistry.
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    Extraordinary tales: Parasites hijacking the minds of hosts
    (Springer India, 2015) Bast, Felix
    In the context of biology, parasites are organisms that typically associate with other organisms, their hosts, such that the hosts are damaged while the parasites are benefited. This nonmutual association is known as parasitism. Parasites do not form an evolutionarily distinct group; instead they are part of many different lineages. For example, there are parasites that are protozoa, plants, fungi and animals. Parasitology refers to the study of parasites, with an emphasize on protozoan (single-celled organisms that belong to Kingdom Protista) parasites. This article examines some of the parasites that cause behavioural changes in their host which help the perpetuation of the parasites; either their spread or their lifecycle completion. Specifically, the article examines the tactics of Toxoplasma gondii, lancet liver fluke, guinea worm, the influenza virus, and the parasitic wasp, which are by all means ?evolution?s neurobiologists?, and are indeed extraordinary in many aspects. ? 2015, Indian Academy of Sciences.
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    Classroom
    (Springer India, 2015) Bast, Felix
    In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with them, or invite responses, or both. ?Classroom? is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science. ? 2015, Indian Academy of Sciences.
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    Chromosomal location of non-hypersensitive leaf rust resistance genes in bread wheat cultivar PBW65 using microsatellite markers
    (2012) Khan, M.A.; Kamaluddin, Saini, R.G.
    Microsatellite or simple sequence repeat (SSRs) markers have been powerful tool for genetic mapping in wheat. Indian bread wheat (Triticum aestivum L.) cultivar PBW65 has shown significant level of resistance to most virulent race 77-5 of leaf rust (Puccinia triticina). It has been indicated that PBW65 expresses non-hypersensitive type of resistance against race 77-5. F2 and F3 crossing of PBW65 with WL711, a leaf rust susceptible wheat cultivar, and allelic tests with such already known genes (present in cultivars RL 6058 and HD 2009) revealed that cultivar PBW65 could be a potential source of novel nonhypersensitive leaf rust resistance genes. So far, only non-hypersensitive leaf rust resistance gene Lr34 was found to be effective under Indian conditions. Attempts to locate such durable leaf rust resistance genes in PBW65 through microsatellite markers showed 2B, 2D and 3D as critical chromosomes for PBW65. The primer Xgwm341 (3D) was found located 41.5 cM away from gene LrPBW1 in PBW65.
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    Amino acid functionalized zinc oxide nanostructures for cytotoxicity effect and hemolytic behavior: Theoretical and experimental studies
    (Elsevier Ltd, 2017) Singh, Satvinder; Singh, Baljinder; Sharma, Prateek; Mittal, Anu; Kumar, Sanjeev; Saini, G.S.S.; Tripathi, S.K.; Singh, Gurinder; Kaura, Aman
    Blending of theoretical and experimental approach, provide an important strategy in designing the nanostructure at a microscopic level and helps in predicting the response of synthesized material towards inhibition of the growth of breast cancer cell. In this work, ab initio calculations using super cell approach are performed for three different amino acids (AAs)-Histidine (His), Arginine (Arg) and Aspartic acid (Asp) coated Zinc oxide (ZnO) nanostructures to explain the growth mechanism of nanoparticles (NPs) of different shapes. Based on the first principles calculations, we reveal that ZnO-AA (Arg and Asp) NPs results in rod like and ZnO-His NPs lead to tablet like configuration. Similar morphologies are fabricated using AAs through synthetic route. The effect of concentration ratio of reactants and pH has been studied. As synthesized samples, are characterized by using Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) and UV?Vis spectroscopy techniques. Based on the results, a plausible mechanism of formation of nanostructures has been proposed. The nanostructures with rod like morphology are found to be biocompatible with normal red blood cells and show cytotoxic effect as evaluated from hemolysis and cytotoxicity assays on breast (MCF-7, T47D, MDA-MB-231) & prostate cancer (PC-3) cell lines. ? 2017 Elsevier Ltd
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    Identification and characterization of novel UniGene-derived microsatellite markers in Podophyllum hexandrum (Berberidaceae).
    (2013) Nag, Akshay; Bhardwaj, Pankaj; Ahuja, Paramvir Singh.; Sharma, Ram Kumar