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Littérature scientifique sur le sujet « Chemical and biological »

Auteur : Grafiati

Publié le 10 mars 2023

Mis à jour le 11 mars 2023

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Articles de revues sur le sujet "Chemical and biological"

Brovarska, O. S., L. D. Varbanets et S. V. Kalinichenko. « Chemical Characterization and Biological Activity of Escherichia coli Lipopolysaccharides ». Mikrobiolohichnyi Zhurnal 82, n^o 6 (30 novembre 2020) : 35–42. http://dx.doi.org/10.15407/microbiolj82.06.035.

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Lipopolysaccharides (LPS) are specific components of the cell envelope of gram-negative bacteria, located at the external surface of their outer membrane and performing a number of important physicochemical and biological functions. The widespread in nature are representatives of Enterobacteriaceae family. Among them there are saprotrophic, useful human symbionts, as well as causative agents of acute intestinal infections. The role of saprophytic intestinal microbiota is not limited only to its participation in the digestion process. The endotoxin released as a result of self-renewal of the cell pool of Escherichia coli partially enters the portal blood and performs antigenic stimulation of the macroorganism. In addition, a small amount of endotoxin can also be released by live gram-negative bacteria, which, given the large population of E. coli in the intestine, can create a sufficiently high concentration of endotoxin. Aim. The study of composition and biological activity of lipopolysaccharides of new E. coli strains, found in the human body. Methods. The objects of investigation were strains of Escherichia coli, isolated from healthy patients at the epidemiological center in Kharkiv. Lipopolysaccharides were extracted from dried cells by 45% phenol water solution at 65–68°С by Westphal and Jann method. The amount of carbohydrates was determined by phenol-sulfuric method. Carbohydrate content was determined in accordance to the calibration curve, which was built using glucose as a standard. The content of nucleic acids was determined by Spirin method, protein − by Lowry method. Serological activity of LPS was investigated by double immunodiffusion in agar using the method of Ouchterlony. Results. In all studied E. coli LPS (2884, 2890, 2892), glucose was dominant monosaccharide (40.5, 41.1, 67.3%, respectively). LPS also contained rhamnose (1.8, 22.9, 1.6%, respectively), ribose (3.5, 6.1, 3.6%, respectively) and galactose (4.1, 20.2, 18.3%, respectively). E. coli 2884 LPS also contained arabinose (1.0%) and mannose (44.8%), while E. coli strains 2890 and 2892 LPS contained heptose (9.7 and 7.8%, respectively). Lipid A composition was presented by fatty acids with a carbon chain length from C12 to C18. As the predominant components were 3-hydroxytetradecanoic (39.2–51.3%) as well as tetradecanoic (23.1–28.5%), dodecanoic (8.9–10.9%), hexadecanoic (4.3–7.2%) and octadecanoic (1.8–2.4%) acids. Unsaturated fatty acids: hexadecenoic (2.0–17.9%) and octadecenoic (3.4–4.2%) have been also identified. It was found that octadecanoic and octadecenoic acids were absent in the LPS of 2884 and 2892 strains, respectively. In SDS-PAAG electrophoresis, a bimodal distribution typical for S-forms of LPS was observed. The studied LPS were toxic and pyrogenic. Double immunodiffusion in agar by Ouchterlony revealed that the tested LPS exhibited an antigenic activity in the homologous system. In heterologous system E. coli 2892 LPS had cross reactivity with LPS of E. coli 2890 and М-17. Since the structure of the O-specific polysaccharide (OPS) of E. coli M-17 was established by us earlier, the results of serological reactions make it possible to suggest an analogy of the E. coli 2892 and 2890 OPS structures with that of E. coli М-17 and their belonging to the same serogroup. Conclusions. The study of the composition and biological activity of LPS of new strains of Escherichia coli 2884, 2890 and 2892, isolated from the body of almost healthy patients, expands our knowledge about the biological characteristics of the species.

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Jumanov, Akhmadzhon Mirzaevich. « The Role And Importance Of Chemical Knowledge In Biological Education ». American Journal of Social Science and Education Innovations 02, n^o 08 (19 août 2020) : 191–94. http://dx.doi.org/10.37547/tajssei/volume02issue08-29.

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Rosenberg, Barbara Hatch. « Biological and Chemical Warfare ». Science 227, n^o 4683 (11 janvier 1985) : 120. http://dx.doi.org/10.1126/science.227.4683.120.a.

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ROSENBERG, B. H. « Biological and Chemical Warfare ». Science 227, n^o 4683 (11 janvier 1985) : 120. http://dx.doi.org/10.1126/science.227.4683.120.

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Gay, Hannah. « Chemical and Biological Warfare ». International History Review 9, n^o 3 (août 1987) : 465–72. http://dx.doi.org/10.1080/07075332.1987.9640453.

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McEwen, Charles N., Frances S. Ligler et Timothy M. Swager. « Chemical and biological detection ». Chemical Society Reviews 42, n^o 22 (2013) : 8581. http://dx.doi.org/10.1039/c3cs90078a.

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SCHUMMER, JOACHIM. « Chemical versus Biological Explanations ». Annals of the New York Academy of Sciences 988, n^o 1 (mai 2003) : 269–81. http://dx.doi.org/10.1111/j.1749-6632.2003.tb06108.x.

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Nylander, C. « Chemical and biological sensors ». Journal of Physics E : Scientific Instruments 18, n^o 9 (septembre 1985) : 736–50. http://dx.doi.org/10.1088/0022-3735/18/9/003.

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Paltin, David M. « Chemical and Biological Violence ». Journal of Threat Assessment 2, n^o 3 (juin 2003) : 41–68. http://dx.doi.org/10.1300/j177v02n03_03.

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Henretig, Fred M., Theodore J. Cieslak et Edward M. Eitzen. « Biological and chemical terrorism ». Journal of Pediatrics 141, n^o 3 (septembre 2002) : 311–26. http://dx.doi.org/10.1067/mpd.2002.127408.

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Thèses sur le sujet "Chemical and biological"

Yukseler, Hande. « Biological And Chemical Sludge Filtration ». Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608608/index.pdf.

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Up to date, sludge filterability has been characterized by the Ruth&rsquo
s classical filtration theory and quantified by the well-known parameter specific cake resistance (SCR). However, the complexity of the actual phenomenon is clearly underestimated by the classical filtration theory and SCR is often not satisfactory in describing filterability. Although many scientific studies were conducted for a better analysis and understanding of the filtration theory, still a practically applicable solution to replace the classical theory for a better description of filterability has not been proposed yet. In the present study, blocking filtration laws proposed by Hermans and Bredé
e, dating back to 1936, which have been extensively used in the membrane literature for the analysis of fouling phenomenon and the multiphase filtration theory developed by Willis and Tosun (1980) highlighting the importance of the cake-septum interface in determining the overall filtration rate have been adopted for the analysis of filterability of sludge systems. Firstly, the inadequacy of the classical filtration theory in characterizing the filterability of real sludge systems and also the lack of the currently used methodology in simulating filtration operation was highlighted. Secondly, to better understand the effect of slurry characteristics and operational conditions on filtration, model slurries of spherical and incompressible Meliodent particles were formed. Finally, a methodology was developed with the gathered filtration data to assess the filterability of the sludge systems by both theories. The results clearly show that both approaches were superior to the classical approach in terms of characterizing the filterability of sludge systems. While blocking laws yielded a slurry specific characterization parameter to replace the commonly used SCR, the multiphase theory provided a better understanding of the physical reality of the overall process.

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Noatch, Matthew R. « An Evaluation of Chemical, Biological, and Combined Chemical-Biological Approaches for Controlling Snails in Aquaculture Ponds ». OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/198.

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Digenetic trematodes are a common pest problem in aquaculture where their unappetizing appearance often reduces the marketability of food fish. Aquatic snails are intermediate hosts in the trematode lifecycle and are commonly targeted with control measures to prevent the crop fish from becoming infected. I evaluated several chemical and biological snail control strategies as alternatives to the potentially invasive black carp. Copper sulfate, hydrated lime slurry, and several fish and decapod species were tested for effectiveness against physid (Physa spp.) and planorbid (Helisoma spp.) snails in laboratory aquaria trials. Hydrated lime demonstrated effectiveness with the least potential to be toxic to cultured fish in regional application. Hybrid sunfish (redear × green sunfish) consumed large quantities of both snails in ad libitum feedings. The most effective biological (redear × green sunfish) and chemical (hydrated lime) control methods identified in the laboratory were evaluated further in research ponds. Hydrated lime applications of 9.07 kg over 9.14 m2 were found to be effective against Helisoma spp. confined to enclosures along the pond shoreline; average survival was 2%. When stocked in aquaculture ponds, hybrid redear sunfish did not significantly influence snail capture rates; however ponds stocked with redear sunfish experienced a gradual decrease in snail populations throughout the 2008 growing season. Hydrated lime and a combination of redear sunfish and hybrid redear sunfish were evaluated separately and in tandem as a combined chemical/biological treatment in the 2009 growing season. Evaluation occurred under mock production conditions in which hybrid striped bass were raised in the research ponds to determine snail treatment effects on trematode abundance. Ponds stocked with sunfish at 494 fish/ha had snail densities significantly (P ≤ 0.05) lower than control ponds after two months. Ponds treated with hydrated lime at 31.7 kg/31.5 m of shoreline in a 1 m swath experienced 99% estimated reductions in snail densities following application, but snail populations rebounded to previous levels within two months. The mean snail density in ponds treated with both hydrated lime and sunfish was significantly lower than control one month post treatment; this mean rebounded slightly by the conclusion of the trial, but not as much as in the chemical treatment group. Hybrid striped bass examined thoroughly for trematodes revealed a positive relationship between trematode abundance in fish and increasing Helisoma densities. This relationship was most apparent when estimates of snail density from only the beginning of the trial were used. Based on these results, it appears that a nearly complete reduction of Helisoma, particularly at the time of stocking fingerlings, is necessary to avoid a high abundance of trematodes in cultured fish. To this end, an early-season application of molluscicides followed closely by stocking of predator sunfish has potential to achieve a uniformly low density of snails throughout the growing season.

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Edwards, John W. « Biological monitoring of occupational chemical exposure / ». Title page, contents and summary only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09phe2652.pdf.

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Peyfoon, Elham. « Chemical and biological properties of propolis ». Thesis, University of Strathclyde, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510828.

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Zhang, Zhibing. « Novel micromanipulation studies of biological and non-biological materials ». Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6512/.

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Many biological and non-biological materials in the form of microscopic particles (or microparticles) are used to produce functional products for a wide range of industrial sectors including pharmaceutical and medical, chemical, agrochemical, food and feed, personal and household care. Understanding their mechanical properties is essential for predicting their behaviour in manufacturing and processing, and for maximising their performance in end-use applications. However, it had not been possible to determine the mechanical properties of single microparticles until the author, as the main contributor, developed a novel micromanipulation technique at the University of Birmingham. The technique is capable of determining the mechanical properties of both biological and non-biological particles as small as 400 nm in diameter, and can be used for obtaining force-displacement data of single microparticles at large deformations, including those corresponding to rupture. The technique was enhanced by mathematical modelling and finite element analysis in order to allow intrinsic material properties to be determined, for example, the particle (or particle wall) elastic modulus, viscoelastic and plastic properties, and stress/strain at rupture. For biological materials, applications of this technique include understanding mechanical damage to animal cells in suspension cultures, yeast and bacterial disruption in downstream processing equipment, biomechanics of chondrocytes and chondrons for tissue engineering, and adhesion and cohesion of biofilms and food fouling deposits. For non-biological materials, applications include understanding and controlling particle breakage in processing equipment, and the formulation of microcapsules with optimum mechanical strength to achieve controlled release and targeted delivery of functional active ingredients. The research on micromanipulation has been sponsored by BBSRC, EPSRC, DEFRA, DTI, EU, the Royal Society K C Wong Fellowships and 19 national and international companies, and has resulted in more than one hundred academic publications. The knowledge generated has also assisted these companies to commercialise particulate functional products.

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Tullett, Jayne Margaret. « Chemical and biological properties of S-nitrosothiols ». Thesis, University of Leicester, 1997. http://hdl.handle.net/2381/30786.

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Since its discovery, nitric oxide (NO) has been identified to influence a large number of physiological processes. This project examines S-nitrosothiols (RSNO) as pro-drugs of NO. The overall aim of this project was to improve our present understanding of the chemical and biological properties of RSNOs. This project has demonstrated that under physiological conditions the stability of RSNOs varies with structure. Results have shown that S-nitrosocysteine and S-nitroso-L-cysteinylgylcine were the least stable of the RSNOs investigated, whereas S-nitroso-N-acetyl-L-cysteine, S-nitroso-3-mercaptopropionic acid and S-nitroso-2-mercapto-ethane sulphonic acid were the most stable. The decomposition of certain RSNOs is catalysed by trace amounts of copper. This phenomenon was particularly evident with the RSNOs, S-nitrosocysteine and S-nitroso-L-cysteinylglycine. Copper catalysed decomposition appears to occur more readily with RSNOs that allow the formation of a stable ring structure, in which Cu+ is bound to the nitrogen of the NO group and another electron-rich atom such as the nitrogen of an amino group. Copper catalysed the decomposition of S-nitrosoglutathione and S-nitroso-L--glutamyl-L-cysteine, but to a lesser extent. Investigations have shown that the decomposition of a stable RSNO is more rapid in the presence of a thiol which gives rise to an unstable RSNO via a transnitrosation reaction. In contrast, decomposition of an unstable RSNO is slower in the presence of a thiol which leads to the formation of a stable RSNO. All RSNOs studied inhibited platelet aggregation and relaxed vascular smooth muscle in a dose dependent manner. In addition, all the RSNOs exhibited a dose-dependent inhibition of growth of A549 cells. Generally no real correlation between the chemical and biological properties of RSNOs was observed. It is clear that there are many factors controlling the release of NO from RSNOs which may have implications regarding the biological activity of these compounds.

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Bunyan, Kerry Emma. « Chemical and biological studies of manganese transferrin ». Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/15569.

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This thesis is concerned with the loading of transferrin with manganese and some of its chemical and biological properties. Manganese is bound to transferrin as Mn(III) with a characteristic ligand (Tyr) to metal (Mn(III) charge-transfer band at a wavelength of 430 nm. Caeruloplasmin is shown to enhance the uptake of manganese from MnC1₂ by apo-hTf. However binding is often incomplete and slow. A novel method of loading hTf with Mn using KMnO₄ is reported. This method leads to rapid uptake and inductively coupled plasma atomic emission spectroscopy (ICP-AES) determinants confirmed the binding of at least two Mn per hTf molecule. The possible oxidising effects of MnO₄^- on protein amino acid side chains was considered. In model systems MnO₄^- oxidises methionine to methionine sulfoxide and methionine sulfone. Evidence of structural changes in apo-hTf induced by Mn(III) binding was obtained by studies using [e-¹³C]Met-hTf. Preliminary work suggests that Mn(III), like several other metals studied, preferentially binds to the C-lobe first, although this may result in an open domain conformation. Fe(III) as Fe(NTA)₂ was found to displace Mn(III) from hhTf but displacement was slower when hTf had been loaded using KMnO₄ rather than MnCl₂. KMnO₄ was not able to displace Fe(III) from Fe₂-hTf. Attempts to crystallise Mn-hTf to characterise these structural changes proved difficult. Crystals grew but were of poor quality and did not diffract. Many large crystals were obtained from solutions of Fe₂-hTf. The crystals were red/orange and ellipsoidal in shape. Of the Fe₂-hTf crystals grown, one diffracted to 3.3 Å with the data being complete to 90%, but not enough information was gained for adequate molecular replacement and structural solution.

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Jiang, Lu. « Chemical synthesis of peptides with biological importance ». Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/12302.

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Thinnes, Cyrille Christophe. « Chemical and biological studies on human oxygenases ». Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:455f2e65-f294-461b-b44f-cd53796b14a0.

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As depicted in Chapter I, 2-oxoglutarate- (2OG) dependent oxygenases are ubiquitous in living systems and display a wide range of cellular functions, spanning metabolism, transcription, and translation. Although functionally diverse, the 2OG oxygenases share a high degree of structural similarities between their catalytic sites. From a medicinal chemistry point of view, the combination of biological diversity and structural similarity presents a rather challenging task for the development of selective small molecules for functional studies in vivo. The non-selective metal chelator 8-hydroxyquinoline (8HQ) was used as a template for the generation of tool compound I for the KDM4 subfamily of histone demethylases via application of the Betti reaction. Structural analogue II was used as the corresponding negative control (Figure A). These compounds were characterised in vitro against a range of 2OG oxygenases and subsequently used for studies in cells. I displays selectivity for KDM4 and increases the level of the H3K9me3 histone mark in cells. It has an effect on the post-translational modification pattern of histone H3, but not other histones, and reduces the viability of lung cancer cells, but not normal lung cells, derived from the same patient. I also stabilises hypoxia-inducable factor HIF in cells via a mechanism which seems to be independent from prolyl hydroxylase inhibition. This work is described in Chapters II and III. The chemical biology research in epigenetics is complemented by qualitative analysis conducted in the social sciences at Said Business School. With a global view on how innovation occurs and may actively be fostered, Chapter IV focuses on the potential of epigenetics in drug discovery and how this process may actively be promoted within the framework of open innovation. Areas of focus include considerations of incremental and disruptive technology; how to claim, demarcate, and control the market; how knowledge brokering occurs; and insights about process, management, organisation, and culture of open innovation. In contrast to the open-skies approach adopted for the development of a tool compound in Chapters II and III, a focused-library approach was taken for the generation of a tool compound for the OGFOD1 ribosomal prolyl hydroxylase. The development of a suitable in vitro activity assay for OGFOD1 in Chapter V enabled the development of lead compound III in Chapter VI. III is selective for OGFOD1 against the structurally closely related prolyl hydroxylase PHD2.

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Lum, Kah Yean. « Chemical and Biological Investigations of Australian Crinoids ». Thesis, Griffith University, 2020. http://hdl.handle.net/10072/395558.

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Natural products (NPs) are commonly defined as the secondary metabolites derived from plants, microorganisms, fungi, insects, and marine invertebrates, as the result of adaptation to the environment or as defense mechanisms against predators. Throughout history, the use of NPs has been described in the form of traditional medicines in different cultures for the treatment of ailments. Apart from their role in medicinal applications, the structures of NPs can also act as lead molecules to inspire the design of new drugs. Of the 1562 new approved drugs by U.S. Food and Drug Administration (FDA) from 1981–2014, 791 (51%) were NPs, NP derivatives or NP-inspired drugs. Since the development of SCUBA in the mid-twentieth century, the marine environment, which contains an incredible diversity of organisms, has been described as the most desired source of NPs for drug discovery research. To date, approximately 35,147 marine natural products (MNPs) had been identified from various organisms, such as marine invertebrates (e.g. sponges, crinoids and ascidians), microorganisms and algae. Many of these MNPs have been found to exhibit a wide variety of pharmaceutically relevant bioactivities, such as anticancer, antimicrobial, antiviral, and anti-inflammatory activities. There are currently 12 marine-derived compounds that have been approved as therapeutic drugs for the treatment of cancer, viral infections, hypertriglyceridemia, and analgesia; while 27 drug candidates are currently in phase I, II, or III clinical trials. While numerous marine invertebrates have been well explored for bioactive MNPs in the last seven decades, crinoids belong to the phylum Echinodermata remained under investigated for their chemistry. Crinoids are the most primitive group of presentday echinoderms. They are known to produce diverse polyketide-derived pigments, which are not only responsible for their colourful appearance, but also have demonstrated significant activity in a range of biomedical assays. There are approximately 700 crinoid species that have been identified worldwide, however, only 36 species have been chemically investigated and only 91 new compounds have been reported to date. Owing to our continuing research interest on crinoid chemistry, the main aim of this PhD project was to identify new chemistry from crinoids sourced from Australian waters and subsequently screen the isolated compounds in a variety of biological assays. The first crinoid project of this thesis focused on the chemistry of the feather star Capillaster multiradiatus since no studies had been undertaken on this Australian species. Capillasterin A, a novel pyrano[2,3-f]chromene, together with seven known naphthopyrones including comaparvin, TMC-256C1, 6-methoxycomaparvin 5-methyl ether, 5,8-dihydroxy-6-methoxy-2-propyl-4H-naphtho[2,3-b]pyran-4-one, 5,8- dihydroxy-6,10-dimethoxy-2-propyl-4H-naphtho[2,3-b]pyran-4-one, TMC-256A1 and 6-methoxycomaparvin were isolated from an EtOH/H2O extract of C. multiradiatus collected by collaborators from the Queensland Museum. The structures of all the compounds were determined by detailed spectroscopic (1D/2D NMR and MS) data analysis. As previous studies demonstrated that HIV gene expression is dependent on the host transcription factor complex NF-B and naphthopyrones were reported to inhibit NF-B signalling pathway, the six known naphthopyrones isolated from this crinoid, together with capillasterin A were screened in an anti-HIV assay. Five known naphthopyrones were observed to display moderate inhibition of in vitro HIV-1 replication in a T cell line with EC50 values ranging from 7.5 to 25.5 μM without concomitant cytotoxicity. The three most abundant compounds, capillasterin A, 6- methoxycomaparvin 5-methyl ether, and TMC-256A1 were also tested for their ability to stimulate the proliferation of GFP-expressing immortalised mouse olfactory ensheathing cells (mOEC) using a cell proliferation assay; none of the compounds showed a significant increase in mOEC viability at 10 μM after 24 hours of treatment. The AIMS Bioresources Library, which consisted of over 3000 marine samples, has recently been transferred to the NatureBank biota repository, which presented us with the opportunity to explore several new crinoid samples from a chemical perspective. Hence, the second PhD project, two AIMS-derived Australian crinoid Comatula rotalaria specimens collected from different locations on the Great Barrier Reef were selected for potential new chemistry, since preliminary UHPLC analysis of these crinoid extracts suggested the presence of new anthraquinone chemistry; only four acyl derivatives of anthraquinones had been identified from this species prior to our studies. Five new taurine-conjugated anthraquinones, named comatulins A−E, together with 11 known metabolites, rhodocomatulin 7-methyl ether, 12-desethylrhodocomatulin 7-methyl ether, rhodocomatulin 5,7-dimethyl ether, 12-desethylrhodocomatulin 5,7-dimethyl ether, rhodocomatulin, rhodolamprometrin, 6-methoxyrhodocomatulin 7-methyl ether, rheoemodin, 6-methoxycomaparvin, 6-methoxycomaparvin 5-methyl ether, and 5,8- dihydroxy-6,10-dimethoxy-2-methyl-4H-benzo[h]chromen-4-one were identified. The structures of all the compounds were elucidated by detailed spectroscopic and spectrometric data analysis. The first X-ray crystal structure of a crinoid-derived acyl anthraquinone, rhodocomatulin 5,7-dimethyl ether, was also obtained. Ten compounds together with two additional naphthopyrone derivatives (comaparvin and 6- methoxycomaparvin 5,8-dimethyl ether) were evaluated for their ability to inhibit HIV-1 replication in vitro; none of the compounds were active at 100 μM. Furthermore, a subset of compounds was tested for their nematocidal activity against Haemonchus contortus, which is a highly pathogenic parasite of small ruminants. The semi-synthetic compound, 6-methoxycomaparvin 5,8-dimethyl ether, showed an inhibitory effect on larval motility (IC50 = 30 μM) and development (IC50 = 31 μM) and induced the eviscerated (Evi) phenotype. In Chapter 4, since none of the crinoid-derived polyketides identified during this PhD had been evaluated for their ability to increase phagocytic activity of human OECs (hOEC), six naphthopyrones and eight anthraquinones were screened using an hOEC phagocytosis assay that has recently been developed by the Clem Jones Centre for Neurobiology and Stem Cell Research group. In addition, microthecaline A and its acetylated, methylated and pivaloylated derivatives, together with antimalarial drug amodiaquine obtained from the in-house Davis compound library, were incorporated into the screening. Results from the primary screening demonstrated that four compounds including 6-methoxycomaparvin 5-methyl ether, 5,8-dihydroxy-6,10-dimethoxy-2- methyl-4H-benzo[h]chromen-4-one, comatulin A, and amodiaquine were found to significantly increase the phagocytic activity and the phagocytic efficiency of hOECs. These findings warrant further investigations in the near future to further expand the preliminary biology results and gain insights in compound specificity and potency. Encouraged by our findings in Chapter 3, we developed a dereplication method using UHPLC-MS for the identification of new sulphur-containing metabolites from Australian crinoids, the details of which are described in Chapter 5. The n-BuOH soluble material of 16 crinoids, including the two C. rotalaria samples described in Chapter 3, were subjected to UHPLC-MS profiling using an optimised method. These crinoids were all sourced from Griffith University’s NatureBank biota repository. The generated UHPLC-MS data were analysed based on the characteristic fragment ions of sulphated compounds in conjunction with scientific database mining; SciFinder Scholar and MarinLit databases were used in this particular study. These investigations led to the large-scale extraction and isolation work on the prioritised crinoid Dichrometra flagellata, which resulted in the isolation of a previously undescribed sulphated compound, which we have tentatively assigned as 5,10-dihydroxy-6–methoxy-8- sulphate-2-propyl-4H-naphtho[2,3-b]pyran-4-one. In summary, this thesis describes the isolation of seven new polyketide constituents and 17 known compounds from four crinoids collected from Australian waters. The chemical structures of all compounds were determined by detailed spectroscopic and spectrometric data analysis. Among all the tested crinoid metabolites, comaparvin was the most active compound in an anti-HIV replication assay, with an IC50 of 7.5 ± 1.7 μM; 6-methoxycomaparvin 5,8-dimethyl ether displayed an inhibitory effect on larval motility (IC50 = 30 μM) and development (IC50 = 31 μM), and induced the Evi phenotype in an anthelmintic assay; 6-methoxycomaparvin 5-methyl ether, 5,8- dihydroxy-6,10-dimethoxy-2-methyl-4H-benzo[h]chromen-4-one, and comatulin A significantly increased the phagocytic activity and the phagocytic efficiency of hOECs. All compounds isolated during this PhD project will be deposited into the Davis Open- Access Compound Library, which is located at Compounds Australia, Griffith University. Compounds Australia makes this academic library available for biological evaluations by both local and international researchers. In addition, the UHPLC-MS methodology developed during these studies enabled the rapid identification of new sulphur-containing compounds from n-BuOH soluble material derived from 16 crinoids, which resulted in the isolation of a new sulphated compound from the prioritised crinoid Dichrometra flagellata; this is the first report of NP chemistry from this crinoid genus. These findings further highlight the importance of UHPLC-MS as a dereplication tool in NP research.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Livres sur le sujet "Chemical and biological"

Clifton, Margaret. Chemical/biological warfare. Washington, D.C. (101 Independence Ave., S.E., Washington 20540-4750) : Science Reference Section, Science, Technology and Business Division, Library of Congress, 2003.

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Marcovitz, Hal. Biological & chemical warfare. Edina, Minn : ABDO, 2010.

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Hibbert, Adam. Biological & chemical warfare. Oxford : Heinemann Library, 2003.

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Biological & chemical warfare. Edina, Minn : ABDO Pub., 2010.

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Spiers, Edward M. Chemical and Biological Weapons. London : Palgrave Macmillan UK, 1994. http://dx.doi.org/10.1057/9780230375642.

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Croddy, Eric, Clarisa Perez-Armendariz et John Hart. Chemical and Biological Warfare. New York, NY : Springer New York, 2002. http://dx.doi.org/10.1007/978-1-4613-0025-0.

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Westwood, Nick J., et Adam Nelson, dir. Chemical and Biological Synthesis. Cambridge : Royal Society of Chemistry, 2018. http://dx.doi.org/10.1039/9781788012805.

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Fouletier, Jacques, et Pierre Fabry, dir. Chemical and Biological Microsensors. Hoboken, NJ, USA : John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118603871.

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Chapitres de livres sur le sujet "Chemical and biological"

Maurer, Richard I., et Christopher A. Reynolds. « Modelling biological systems ». Dans Chemical Modelling, 199–238. Cambridge : Royal Society of Chemistry, 2007. http://dx.doi.org/10.1039/9781847553317-00199.

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Stout, Marguerite A. « Chemical Skinning ». Dans Calcium in Biological Systems, 399–410. Boston, MA : Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2377-8_44.

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Dando, Malcolm R. « The Chemical Weapons Convention and the Worldwide Chemical Industry ». Dans Preventing Biological Warfare, 23–40. London : Palgrave Macmillan UK, 2002. http://dx.doi.org/10.1057/9781403907196_2.

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Tabib-Azar, Massood. « Chemical and Biological Microactuators ». Dans Microactuators, 197–218. Boston, MA : Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5445-5_7.

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Fraden, Jacob. « Chemical and Biological Sensors ». Dans Handbook of Modern Sensors, 645–97. Cham : Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-19303-8_18.

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Lau, William K. M., Duane E. Waliser et Baijun Tian. « Chemical and biological impacts ». Dans Intraseasonal Variability in the Atmosphere-Ocean Climate System, 569–85. Berlin, Heidelberg : Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-13914-7_18.

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Parker, David F. « Chemical and Biological Models ». Dans Springer Undergraduate Mathematics Series, 207–35. London : Springer London, 2003. http://dx.doi.org/10.1007/978-1-4471-0019-5_10.

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Gargaud, Muriel, Ricardo Amils, Carlos Briones, Henderson James Cleaves et Felipe Gomez. « Chemical and Biological Data ». Dans Encyclopedia of Astrobiology, 2705–12. Berlin, Heidelberg : Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-44185-5_5071.

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Jaffrezic-Renault, Nicole. « Chemical and Biological Recognition ». Dans Chemical Sensors and Biosensors, 1–25. Hoboken, NJ, USA : John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118561799.ch1.

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Gargaud, M., R. Amils, C. Briones, J. Cleaves et F. Gomez. « Chemical and Biological Data ». Dans Encyclopedia of Astrobiology, 1825–30. Berlin, Heidelberg : Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-11274-4_5071.

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Actes de conférences sur le sujet "Chemical and biological"

Swim, Cindy, Richard Vanderbeek et Darren Emge. « Chemical-Biological Detection Overview ». Dans International Quantum Electronics Conference. Washington, D.C. : OSA, 2009. http://dx.doi.org/10.1364/iqec.2009.pwa1.

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Swim, Cindy, Richard Vanderbeek et Darren Emge. « Chemical-Biological Detection Overview ». Dans Conference on Lasers and Electro-Optics. Washington, D.C. : OSA, 2009. http://dx.doi.org/10.1364/cleo.2009.pwa1.

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Arrieta, Rudy T., et Jay S. Huebner. « Photoelectric chemical and biological sensors ». Dans AeroSense 2000, sous la direction de Patrick J. Gardner. SPIE, 2000. http://dx.doi.org/10.1117/12.394058.

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Nossal, Ralph. « Photon Migration in Biological Tissue ». Dans Laser Applications to Chemical Analysis. Washington, D.C. : Optica Publishing Group, 1992. http://dx.doi.org/10.1364/laca.1992.mc4.

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In recent years considerable effort has been given to developing noninvasive diagnostic procedures which utilize light to penetrate optically turbid biological tissues. Among these are pulse oximetry1,2 and time-resolved absorption spectroscopy3–5 to assess regional blood oxygenation, laser Doppler techniques to measure peripheral blood flow,6 and imaging modalities to discern tumours or other tissue inhomogenities.7–9 These methods, which are directed towards the analysis of living tissues, rely upon photons which have migrated through a highly scattering tissue matrix before being re-emitted and detected at an accessible surface.

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Phelps, Kirkman R. « Chemical/Biological Agent Stand-Off Detection ». Dans 1988 Los Angeles Symposium--O-E/LASE '88, sous la direction de Frank Allario. SPIE, 1988. http://dx.doi.org/10.1117/12.944247.

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Buttgenbach, Stephanus. « Microsystems for chemical and biological sensing ». Dans 2007 International Workshop on Physics of Semiconductor Devices. IEEE, 2007. http://dx.doi.org/10.1109/iwpsd.2007.4472605.

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Moller, Sven, Garry D. Hinch, Kenneth J. Duda, Pavel Kornilovitch, Kevin F. Peters, Kenneth Ward, Qingqiao Wei et Xioafeng Yang. « Nano-scale chemical and biological sensors ». Dans Optics East 2005, sous la direction de M. Saif Islam et Achyut K. Dutta. SPIE, 2005. http://dx.doi.org/10.1117/12.634534.

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Sun, Yuze, et Xudong Fan. « Optofluidics in chemical and biological analysis ». Dans Frontiers in Optics. Washington, D.C. : OSA, 2012. http://dx.doi.org/10.1364/fio.2012.ftu2c.1.

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Elsamny, Maged F. « Tomorrow’s Architecture : Biological NanoArchiecture ». Dans 14th Asia Pacific Confederation of Chemical Engineering Congress. Singapore : Research Publishing Services, 2012. http://dx.doi.org/10.3850/978-981-07-1445-1_657.

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Dovichi, Norman J., Shade Wu et Da Yung Chen. « High Sensitivity Fluorescence Detection of Biological Molecules ». Dans Laser Applications to Chemical Analysis. Washington, D.C. : Optica Publishing Group, 1990. http://dx.doi.org/10.1364/laca.1990.tha1.

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Fluorescein is a good fluorescent label for high sensitivity analysis. The molecule has high molar absorptivity, 5 × 104 L mol-1 cm-1 at 488 nm and near unit fluorescence quantum yield in the pH range of 8 to 10. Unfortunately, the molecule is not photostable undergoing irreversible photobleaching after absorbance of about 8,000 photons. Fluorescein may be used to label amino groups in amino acids, peptides, and proteins through the isothiocyanate derivative. Under basic conditions, the thiocarbamoyl derivative is formed, with relatively good stability. The reaction between amino acids and fluorescein isothiocyanate is first order in bod the concentration of amino acid and derivative, with an activation energy of about 16 kcal/mol. Under acidic conditions, the cyclic thiohydantoin derivative is formed, cleaving the terminal amino acid from proteins and peptides. This thiohydantoin derivative possesses greater photostability than the thiocarbamoyl derivative, decomposing after absorbance of about 12,000 photons. The thiocarbamoyl-thiohydantoin derivative series is the basis of an Edmon degradation scheme for protein sequencing. In addition to amino acid labeling, fluorescein may be used to label thiols through the bromobimane derivatives; a high sensitivity DNA analysis is based on this compound. Last, succinylfluorescein labeled chain terminating dideoxynucleotides are used in DNA sequencing, these molecules have similar spectral properties as fluorescein.

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Rapports d'organisations sur le sujet "Chemical and biological"

Fitch, P. J. Biological and Chemical Security. Office of Scientific and Technical Information (OSTI), décembre 2002. http://dx.doi.org/10.2172/15006003.

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Schoomaker, Peter J., et Sandra R. Riley. Classification of Former Chemical Warfare, Chemical and Biological Defense, and Nuclear, Biological, and Chemical Contamination Survivability Information. Fort Belvoir, VA : Defense Technical Information Center, juin 2005. http://dx.doi.org/10.21236/ada440765.

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Nayfack, Nicholas, et Robert W. MacDougall. Chemical Biological Defense (CBD) Simulations. Fort Belvoir, VA : Defense Technical Information Center, juillet 1996. http://dx.doi.org/10.21236/ada396828.

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Havel, Mickael, Dale W., Naiping Hu et Tom Martin. Chemical and Biological Resistant Clothing. Fort Belvoir, VA : Defense Technical Information Center, avril 2013. http://dx.doi.org/10.21236/ada582844.

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Hartman, Nile F., Daniel P. Campbell et Janet Cobb. Integrated Optic Chemical-Biological Sensors. Fort Belvoir, VA : Defense Technical Information Center, février 1999. http://dx.doi.org/10.21236/ada385370.

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Price, Barbara B. Chemical Biological Medical Treatment Symposia-III. Fort Belvoir, VA : Defense Technical Information Center, avril 2001. http://dx.doi.org/10.21236/ada394695.

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Tsui, Jeffrey. Extracting Chemical Reactions from Biological Literature. Fort Belvoir, VA : Defense Technical Information Center, mai 2014. http://dx.doi.org/10.21236/ada605115.

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Johnson-Winegar, Anna. DoD Chemical/Biological Defense Program Overview. Fort Belvoir, VA : Defense Technical Information Center, avril 2002. http://dx.doi.org/10.21236/ada422847.

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Carrano, John. Chemical and Biological Sensor Standards Study. Fort Belvoir, VA : Defense Technical Information Center, janvier 2005. http://dx.doi.org/10.21236/ada458370.

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Sidell, Frederick R., Ernest T. Takafuji et David R. Franz. Medical Aspects of Chemical and Biological Warfare. Fort Belvoir, VA : Defense Technical Information Center, janvier 1997. http://dx.doi.org/10.21236/ada398241.

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