Academic literature on the topic 'Diterpeni'
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Journal articles on the topic "Diterpeni"
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Pruteanu, Elena, Vladilena Gîrbu, Nicon Ungur, Leentje Persoons, Dirk Daelemans, Philippe Renaud, and Veaceslav Kulcițki. "Preparation of Antiproliferative Terpene-Alkaloid Hybrids by Free Radical-Mediated Modification of ent-Kauranic Derivatives." Molecules 26, no. 15 (July 28, 2021): 4549. http://dx.doi.org/10.3390/molecules26154549.
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A convenient strategy for molecular editing of available ent-kauranic natural scaffolds has been developed based on radical mediated C–C bond formation. Iodine atom transfer radical addition (ATRA) followed by rapid ionic elimination and radical azidoalkylation were investigated. Both reactions involve radical addition to the exo-methylenic double bond of the parent substrate. Easy transformations of the obtained adducts lead to extended diterpenes of broad structural diversity and artificial diterpene-alkaloid hybrids possessing lactam and pyrrolidine pharmacophores. The cytotoxicity of selected diterpenic derivatives was examined by in vitro testing on several tumor cell lines. The terpene-alkaloid hybrids containing N-heterocycles with unprecedented spiro-junction have shown relevant cytotoxicity and promising selectivity indexes. These results represent a solid basis for following research on the synthesis of such derivatives based on available natural product templates.
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Tazawa, Shigemi, Yasuko Arai, Sho Hotta, Taichi Mitsui, Hiroshi Nozaki, and Kenji Ichihara. "Discovery of a Novel Diterpene in Brown Propolis from the State of Parana, Brazil." Natural Product Communications 11, no. 2 (February 2016): 1934578X1601100. http://dx.doi.org/10.1177/1934578x1601100218.
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Propolis is a resinous substance collected by honeybees from certain plant sources. The components of propolis depend on the vegetation of the area in which apiculture is practiced. In Brazil, there are several types of propolis including ‘green,’ ‘red’ and ‘brown'. Brazilian brown propolis from the state of Parana characteristically includes diterpenes, and we discovered a novel clerodane diterpene, rel-(5 S,6 S,8 R,9 R,10 S,18 R,19 S)-18,19-epoxy-2-oxocleroda-3,12( E),14-triene-6,18,19-triol 18,19-diacetate 6-benzoate (3) and five known diterpenes (1, 2, 4, 5 and 6). The chemical structure of the novel diterpene 3 was determined using 1D- and 2D-NMR spectroscopic analyses. Furthermore, the activities of the isolated diterpenes on growth inhibition of several human cancer cell lines (LNCaP, MCF-7, DLD-1 and A549) were evaluated in vitro; diterpene 3 exhibited a potent inhibition of cell growth, and its activity was approximately 15 times higher than that of the other diterpenes.
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Yazdiniapour, Zeinab, Mohammad Hossein Sohrabi, Newsha Motinia, Behzad Zolfaghari, Pegah Mehdifar, Mustafa Ghanadian, and Virginia Lanzotti. "Diterpenoids from Euphorbia gedrosiaca as Potential Anti-Proliferative Agents against Breast Cancer Cells." Metabolites 13, no. 2 (February 3, 2023): 225. http://dx.doi.org/10.3390/metabo13020225.
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Isolated diterpenes from various species of Euphorbia are important compounds for drug discovery with a broad spectrum of structures and biological effects. In this study, Euphorbia gedrosiaca, one of the endemic species of Iran, was analyzed in terms of the presence and structural determination of diterpenoid compounds. They were extracted with dichloromethane/acetone (2:1) from aerial parts of this plant and purified by chromatographic methods such as MPLC and HPLC. Four premyrsinane compounds and one myrsinane diterpene were isolated from Euphorbia gedrosiaca. They were characterized by extensive 1D and 2D NMR and HRMS analyses. Additionally, their activities were evaluated against two breast cancer cell lines, MDA-MB-231 and MCF-7, by MTT proliferation assay. They exhibited cytotoxic effects in a dose-dependent manner with promising results, which can help to find possible therapeutic application of diterpenoids in breast cancer treatment.
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Alicandri, Enrica, Stefano Covino, Bartolomeo Sebastiani, Anna Rita Paolacci, Maurizio Badiani, Francesco Manti, Carmelo Peter Bonsignore, Agostino Sorgonà, and Mario Ciaffi. "Diterpene Resin Acids and Olefins in Calabrian Pine (Pinus nigra subsp. laricio (Poiret) Maire) Oleoresin: GC-MS Profiling of Major Diterpenoids in Different Plant Organs, Molecular Identification and Expression Analysis of Diterpene Synthase Genes." Plants 10, no. 11 (November 5, 2021): 2391. http://dx.doi.org/10.3390/plants10112391.
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A quali-quantitative analysis of diterpenoid composition in tissues obtained from different organs of Pinus nigra subsp. laricio (Poiret) Maire (Calabrian pine) was carried out. Diterpene resin acids were the most abundant diterpenoids across all the examined tissues. The same nine diterpene resin acids were always found, with the abietane type prevailing on the pimarane type, although their quantitative distribution was found to be remarkably tissue-specific. The scrutiny of the available literature revealed species specificity as well. A phylogeny-based approach allowed us to isolate four cDNAs coding for diterpene synthases in Calabrian pine, each of which belonging to one of the four groups into which the d3 clade of the plants’ terpene synthases family can be divided. The deduced amino acid sequences allowed predicting that both monofunctional and bifunctional diterpene synthases are involved in the biosynthesis of diterpene resin acids in Calabrian pine. Transcript profiling revealed differential expression across the different tissues and was found to be consistent with the corresponding diterpenoid profiles. The isolation of the complete genomic sequences and the determination of their exon/intron structures allowed us to place the diterpene synthase genes from Calabrian pine on the background of current ideas on the functional evolution of diterpene synthases in Gymnosperms.
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Li, Fang-Ru, Xiaoxu Lin, Qian Yang, Ning-Hua Tan, and Liao-Bin Dong. "Efficient production of clerodane and ent-kaurane diterpenes through truncated artificial pathways in Escherichia coli." Beilstein Journal of Organic Chemistry 18 (July 21, 2022): 881–88. http://dx.doi.org/10.3762/bjoc.18.89.
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The clerodane and ent-kaurane diterpenoids are two typical categories of diterpenoid natural products with complicated polycyclic carbon skeletons and significant pharmacological activities. Despite exciting advances in organic chemistry, access to these skeletons is still highly challenging. Using synthetic biology to engineer microbes provides an innovative alternative to bypass synthetic challenges. In this study, we constructed two truncated artificial pathways to efficiently produce terpentetriene and ent-kaurene, two representative clerodane and ent-kaurane diterpenes, in Escherichia coli. Both pathways depend on the exogenous addition of isoprenoid alcohol to reinforce the supply of IPP and DMAPP via two sequential phosphorylation reactions. Optimization of these constructs provided terpentetriene and ent-kaurene titers of 66 ± 4 mg/L and 113 ± 7 mg/L, respectively, in shake-flask fermentation. The truncated pathways to overproduce clerodane and ent-kaurane skeletons outlined here may provide an attractive route to prepare other privileged diterpene scaffolds.
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Reddy, Priyanka, Kathryn Guthridge, Simone Vassiliadis, Joanne Hemsworth, Inoka Hettiarachchige, German Spangenberg, and Simone Rochfort. "Tremorgenic Mycotoxins: Structure Diversity and Biological Activity." Toxins 11, no. 5 (May 27, 2019): 302. http://dx.doi.org/10.3390/toxins11050302.
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Indole-diterpenes are an important class of chemical compounds which can be unique to different fungal species. The highly complex lolitrem compounds are confined to Epichloë species, whilst penitrem production is confined to Penicillium spp. and Aspergillus spp. These fungal species are often present in association with pasture grasses, and the indole-diterpenes produced may cause toxicity in grazing animals. In this review, we highlight the unique structural variations of indole-diterpenes that are characterised into subgroups, including paspaline, paxilline, shearinines, paspalitrems, terpendoles, penitrems, lolitrems, janthitrems, and sulpinines. A detailed description of the unique biological activities has been documented where even structurally related compounds have displayed unique biological activities. Indole-diterpene production has been reported in two classes of ascomycete fungi, namely Eurotiomycetes (e.g., Aspergillus and Penicillium) and Sordariomycetes (e.g., Claviceps and Epichloë). These compounds all have a common structural core comprised of a cyclic diterpene skeleton derived from geranylgeranyl diphosphate (GGPP) and an indole moiety derived from tryptophan. Structure diversity is generated from the enzymatic conversion of different sites on the basic indole-diterpene structure. This review highlights the wide-ranging biological versatility presented by the indole-diterpene group of compounds and their role in an agricultural and pharmaceutical setting.
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Ye, Ke, and Hong-lian Ai. "Pimarane Diterpenes from Fungi." Pharmaceuticals 15, no. 10 (October 20, 2022): 1291. http://dx.doi.org/10.3390/ph15101291.
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Pimarane diterpenes are a kind of tricyclic diterpene, generally isolated from plant and fungi. In nature, fungi distribute widely and there are nearly two to three million species. They provide many secondary metabolites, including pimarane diterpenes, with novel skeletons and bioactivities. These natural products from fungi have the potential to be developed into clinical medicines. Herein, the structures and bioactivities of 197 pimarane diterpenes are summarized and the biosynthesis and pharmacological researches of pimarane diterpenes are introduced. This review may be useful improving the understanding of pimarane diterpenes from fungi.
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Liu, Zhang, Wu, Chen, Li, Dai, and Wang. "Four New ent-Kaurane Diterpene Glycosides from Isodon henryi." Molecules 24, no. 15 (July 27, 2019): 2736. http://dx.doi.org/10.3390/molecules24152736.
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To obtain diterpene glycosides from an aqueous extract of the aerial parts of Isodon henryi and further investigate their cytotoxicities, in this study, a total of seven compounds were isolated, including six ent-kaurane diterpene glycosides (1–6) and one diterpene aglycon (7). Among the seven ent-kaurane diterpenes obtained, four were novel compounds, including ent-7,20-epoxy- kaur-16-en-1α,6β,7β,15β-tetrahydroxyl-11-O-β-d-glucopyranoside (1), ent-7,20-epoxy-kaur-16-en- 6β,7β,14β,15β-tetrahydroxyl-1-O-β-d-glucopyranoside (2), ent-7,20-epoxy-kaur-16-en-6β,7β,15β- trihydroxyl-1-O-β-d-glucopyranoside (3), and ent-7,20-epoxy-kaur-16-en-7β,11β,14α,15β-tetrahydr- oxyl-6-O-β-d-glucopyranoside (4), and three were isolated from this plant for the first time (5–7). Their structures were elucidated by utilizing spectroscopic methods and electronic circular dichroism analyses. Furthermore, the cytotoxicities of all seven compounds were investigated in four human cancer cell lines, including A2780, BGC-823, HCT-116, and HepG2. The IC50 values of these diterpenes ranged from 0.18 to 2.44 mM in the tested cell lines. In addition, the structure–cytotoxicity relationship of diterpene glycosides was also evaluated to study the effect of glycosylation on the cytotoxicity of diterpene compounds.
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Eren, Fatma Hulyam, and Halit Tanju Besler. "Bioactive diterpenes (cafestol and kahweol) in Turkish coffees: Impact of roasting." International Food Research Journal 29, no. 2 (April 1, 2022): 328–37. http://dx.doi.org/10.47836/ifrj.29.2.11.
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While the cholesterol-raising effect of coffee has been ascribed to the presence of diterpenes, they have also been shown to present favourable health effects. Boiled-type coffees show slightly higher levels of diterpenes than those made with other brewing methods. However, there is considerable controversy regarding the effect of roasting on the contents of the diterpenes cafestol and kahweol. Therefore, the aim of the present work was to measure the contents of these diterpenes in Turkish coffees, and to determine how they are influenced by roasting. The samples used were 16 roasted and ready-ground Turkish coffees sold in supermarkets in the Turkish Republic of Northern Cyprus. The cafestol and kahweol contents of the coffee samples were analysed using liquid-liquid extraction followed by HPLC-DAD. The lipid contents of commercially roasted and ground Turkish coffee samples varied in the range of 14.32 ± 0.09 to 15.60 ± 0.09 g/100 g. The lipid contents of brewed Turkish coffee samples varied from 318 ± 2.00 to 571 ± 4.30 mg/100 mL. When compared within each commercial brand, dark roasted ground Turkish coffee samples had higher lipid contents. The average diterpene content in one cup of Turkish coffee sample was between 2.69 ± 0.28 and 13.58 ± 0.88 mg. The ranges of cafestol and kahweol contents in a cup were 1.4 ± 0.21 - 6.9 ± 0.65 mg and 1.28 ± 0.07 - 6.68 ± 0.28 mg, respectively. Within products of the same brand, the highest amount of oil was observed in dark roasted Turkish coffee beverages, and no significant differences were found in total diterpene, cafestol, and kahweol contents in coffee beverages among the different roasting levels. It is recommended that future studies perform more detailed investigations of the effect of roasting on the diterpene contents in Turkish coffees, and the impact of preparation parameters, as well as the presence of diterpene-derived compounds.
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Wollenweber, Eckhard, Marion Dörr, Marco Dörsam, Abu El-Hamed Hassan, Ahmed A. Ahmed, M. F. Hegazy, and Klaus-Peter Zeller. "Flavonoids and Terpenoids from the Resinous Exudates of Madia Species (Asteraceae, Helenieae)." Zeitschrift für Naturforschung C 58, no. 3-4 (April 1, 2003): 153–60. http://dx.doi.org/10.1515/znc-2003-3-401.
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The resinous material accumulated on aerial parts of Madia species is shown to consist mainly of diterpenes, containing a series of flavonoid aglycones. A6- and/or 8-O-substitution is characteristic for many of these flavonoids. Three known rare diterpenes were found and the structure elucidation of a diterpene with a new carbon skeleton, named madiaol, is reported.
Dissertations / Theses on the topic "Diterpeni"
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Alfieri, Mariaevelina. "Transcriptional regulation of biosynthetic genes of the plant MEP-derived pathway to boost the metabolic flux towards bioactive diterpenes." Doctoral thesis, Universita degli studi di Salerno, 2016. http://hdl.handle.net/10556/2066.
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2013 - 2014This project was aimed at enhancing the synthesis of tri-cyclic bioactive abietane diterpenes (e.g. aethiopinone, 1-oxoaethiopinone, salvipisone, and ferruginol), synthesized in the roots of Salvia sclarea and other Salvia species, with known anti-inflammatory and antitumoral activities. There is a great demand of novel molecules to treat melanoma, the most aggressive form of skin cancer, since advanced stages are inevitably resistant to conventional therapeutic agents.We have recently shown that aethiopinone is cytotoxic against the human melanoma A357 cell line at a concentration not toxic to normal cells. In addition, by using the web server IdTarget a number of putative proteins overexpressed in melanoma were identified as potential cellular target of aethiopinone. Despite this interesting evidence, this compound can not be easily synthesized by chemical means, and it is only produced in the roots of Salvia species in minute amounts (less than 0.5% DW) wich are not sufficient to yield reliable amounts for a deeper understanding of their molecular targets and potential future commercialization. In order to produce sufficient quantity of this interesting class of compounds, we targeted the plastidial terpenoid MEP-dependent pathway, from which they derive, by two different metabolic engineering strategies in S. sclarea hairy roots. The first approach was based on the coordinated activation of MEP-pathway biosynthetic genes by elicitation or by overexpression of transcription factors. An enhanced content (about a 20-fold increase) of abietane diterpenes in S. sclarea hairy roots was induced by elicitation with Methyl-Jasmonate (MJ), due to the increased expression levels of the several MEP-pathway biosynthetic genes, indicating a possible coordinate gene regulation by transcription factors. Four transcription factors (WRKYs and Myc2) of A. thaliana were selected on the basis of the presence of MJRE-box in their promoter region. Overexpression of AtWRKY and AtMyc2 genes in S. sclarea hairy roots positively regulated transcription of several genes of the terpenoid MEP-pathway. High-level induced-expression of genes acting up-stream [1-Deoxy-D-Xylulose-5-Phosphate Synthase (DXS) and 1-Deoxy-D-Xylulose-5-Phosphate Reductoisomerase (DXR)] or downstream [geranylgeranyl-diphosphate synthase (GGPPS) and copalyl-diphosphate synthase (CPPS)] of this pathway, correlated with high-level of abietane-type diterpenes (3-5 fold increase). To our knowledge, this is the first evidence of TFs activating this specific diterpene pathway. One drawback of this strategy was the impaired growth, at varying level, of transgenic S. sclarea hairy roots. However, it was possible to select the best performing over-expressing hairy root lines in which high final biomass was coupled to high content of abietane diterpenes. The second strategy was aimed at blocking the Ent-copalyl-diphosphate synthase (Ent-CPPS), the first enzyme acting at the lateral competing route from GGPP to gibberellins. Either chemical inhibition of the enzymatic activity of Ent-CPPS with CCC (chlorocholine chloride), a known plant growth retardant, or RNAi-mediated silencing of this gene in S. sclarea hairy roots enhanced significantly (>4-fold) the total abietane diterpenes content, without causing any growth impairment compared to control hairy roots. Overall, these complementary approaches were successful in increasing the content of aethiopinone and other tricyclic abietane diterpenes (from a 3-fold up to a 5-fold increase compared to the content in the control line) in engineered S. sclarea hairy roots and might be extended to different plant species synthesizing other bioactive specialized terpenes. Moreover, the combination of these two approaches are expected to further enhance the accumulation of abietane diterpenes, as for chemical elicitation (with MJ, coronatine etc) coupled with metabolic engineering approaches, currently in progress in our laboratory, are also expected to increase the efficiency of the synthesis of this interesting class of compounds. Finally, the promising results presented in this study pave the way to a rational design of a hairy root-based production platform to yield reliable amounts of tricyclic abietane diterpenes towards a deeper understanding of their molecular targets and the potential future exploitation as novel plant-derived anti-tumor molecules. [edited by author]
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Sousa, Antonio Honório de. "Estudo químico de Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae)." reponame:Repositório Institucional da UFC, 2014. http://www.repositorio.ufc.br/handle/riufc/20076.
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SOUSA, Antonio Honório de. Estudo químico de Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae). 2014. 279 f. Tese (Doutorado em química)- Universidade Federal do Ceará, Fortaleza-CE, 2014.Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-10-04T15:43:43Z No. of bitstreams: 1 2014_tese_ahsousa.pdf: 13571451 bytes, checksum: dcde11370b56473403f20f179360abe9 (MD5)
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The present work reports the chemical study related to the stem and the roots of Croton limae, collected in Andaraí/BA. The phytochemical investigation of ethanol extract from the stem lead to the isolation of two kaurane-type diterpenes, ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid, two clerodane-type diterpenes, 3,12-dioxo-15,16-epoxy-4α-hydroxycleroda-13(16),14-diene and 3-oxo-4α-hydroxy-13,14,15,16-tetranorclerodan-12-oic acid, and the flavonoid quercetin 3-O-β-D-glucopyranoside. The investigation of the hexane extract from the roots lead to the isolation of one triterpene, acetyl aleuritolic acid, the new dimer ent-17(α-pinen-10’-yl)-15-oxokauran-18-oic acid, two news clerodane diterpenes, 3-oxo-15,16-epoxy-4α,12-dihydroxycleroda-13(16),14-diene and 15,16-epoxy-3α,4α,12-trihydroxycleroda-13(16),14-diene, one halimane-type diterpene, 15,16-epoxy-3α,12-dihydroxyhalima-5(10),13(16),14-triene and the mixture of steroids β-sitosterol and stigmasterol. From the ethanol extract of the roots, it was possible to isolate the flavonoids kaempferol 3-O-β-glucopyranoside and ombuine 3-O-β-rutinoside and the three new clerodane diterpenes 3α,4α,15,16-tetrahydroxyclerod-13-ene, 6-(β-D-glucopyranosyl)-3,12-dioxo-15,16-epoxi-4α-hydroxycleroda-13(16),14-dieno and 3-oxo-4α,12-dihydroxy-14,15,16-trinorclerodan-13-oic acid. Four aromatic derivatives amides from ent-kaur-16-en-18-oic acid were prepared through nucleophilic substitutive reactions. The corresponding methyl esters from the ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid were also obtained. Two new derivatives from 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno were prepared through reduction reaction and another one by the biotransformation of diterpene, made by the fungus Rhizopus stolonifer. Some isolated compounds and derivatives were submited to cytotoxic activity using ovarian (OVCAR-8), glioblastoma (SF-295) and colon (HCT-116) cell lines, and the compounds ent-kaur-16-en-15-oxo-18-oic acid and ent-17(α-pinen-10’-yl)-15-oxokauran-18-oic acid registered activity during preliminaries assays. The secondary metabolites were isolated through usual chromatography techniques, using thin layer chromatography, column chromatography, size exclusion chromatography and high performance liquid chromatography. The determination of the structure of the isolated compounds was performed through physical (melting point and optical rotation) and spectrometric techniques, such infrared (IR), high resolution mass spectrometry and nuclear magnetic resonance (NMR), including bidimensional experiments, and comparison with literature data.
O presente trabalho relata o estudo químico do caule e das raízes de Croton limae, coletado no município de Andaraí-BA. A investigação fitoquímica do extrato etanólico do caule levou ao isolamento de dois diterpenos do tipo caurano, ácido ent-caur-16-en-18-oico e ácido ent-caur-16-en-15-oxo-18-oico, dois diterpenos do tipo clerodano, 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e ácido 3-oxo-4α-hidroxi-13,14,15,16-tetranorclerodan-12-oico, e do flavonoide 3-O-β-D-glicopiranosilquercetina. A investigação do extrato hexânico das raízes levou ao isolamento de um triterpeno, ácido acetilaleuritólico, do dímero inédito ácido ent-17(α-pinen-10’-il)-15-oxocauran-18-oico, de dois novos diterpenos clerodanos, 3-oxo-15,16-epoxi-4α,12-dihidroxicleroda-13(16),14-dieno e 15,16-epoxi-3α,4α,12-trihidroxicleroda-13(16),14-dieno, um diterpeno do tipo halimano, 15,16-epoxi-3α,12-dihidroxihalima-5(10),13(16),14-trieno, e da mistura dos esteroides β-sitosterol e estigmasterol. Do extrato etanólico das raízes foram isolados dois flavonoides, 3-O-β-D-glicopiranosilcanferol e ombuina-3-O-β-rutinosídeo, e três diterpenos clerodanos inéditos, 3α,4α,15,16-tetrahidroxicleroda-13-eno, 6-(β-D-glicopiranosil)-3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e ácido 3-oxo-4α,12-dihidroxi-14,15,16-trinorclerodan-13-oico. Foram preparadas quatro amidas aromáticas derivadas do ácido ent-caur-16-en-18-oico e os respectivos ésteres metílicos dos ácidos ent-caur-16-en-18-oico e ent-caur-16-en-15-oxo-18-oico. Foram preparados dois derivados reacionais obtidos através de reações de redução do diterpeno clerodano 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e outro através da biotransformação deste diterpeno pelo fungo Rhizopus stolonifer. Alguns compostos isolados e derivados foram submetidos a testes de atividade citotóxica, utilizando linhagens de células tumorais de ovário (OVCAR-8), glioblastoma (SF-295) e colón (HCT-116), onde testes preliminares indicaram que os compostos ent-caur-16-en-15-oxo-18-oico e ácido ent-17(α-pinen-10’-il)-15-oxocauran-18-oico apresentaram atividade. Os metabólitos secundários foram isolados através de técnicas cromatográficas usuais, utilizando cromatografia em camada delgada, cromatografia em coluna, cromatografia por exclusão molecular e cromatografia líquida de alta eficiência. A determinação estrutural foi realizada através de métodos físicos (ponto de fusão e rotação óptica) e do uso de técnicas espectroscópicas e espectrométricas como infravermelho (IV), espectrometria de massas de alta resolução e ressonância magnética nuclear de hidrogênio (RMN 1H) e carbono-13 (RMN 13C), incluindo experimentos bidimensionais, além de comparação com dados da literatura.
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Sousa, Antonio HonÃrio de. "Estudo quÃmico de Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae)." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=14361.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorThe present work reports the chemical study related to the stem and the roots of Croton limae, collected in AndaraÃ/BA. The phytochemical investigation of ethanol extract from the stem lead to the isolation of two kaurane-type diterpenes, ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid, two clerodane-type diterpenes, 3,12-dioxo-15,16-epoxy-4α-hydroxycleroda-13(16),14-diene and 3-oxo-4α-hydroxy-13,14,15,16-tetranorclerodan-12-oic acid, and the flavonoid quercetin 3-O-β-D-glucopyranoside. The investigation of the hexane extract from the roots lead to the isolation of one triterpene, acetyl aleuritolic acid, the new dimer ent-17(α-pinen-10â-yl)-15-oxokauran-18-oic acid, two news clerodane diterpenes, 3-oxo-15,16-epoxy-4α,12-dihydroxycleroda-13(16),14-diene and 15,16-epoxy-3α,4α,12-trihydroxycleroda-13(16),14-diene, one halimane-type diterpene, 15,16-epoxy-3α,12-dihydroxyhalima-5(10),13(16),14-triene and the mixture of steroids β-sitosterol and stigmasterol. From the ethanol extract of the roots, it was possible to isolate the flavonoids kaempferol 3-O-β-glucopyranoside and ombuine 3-O-β-rutinoside and the three new clerodane diterpenes 3α,4α,15,16-tetrahydroxyclerod-13-ene, 6-(β-D-glucopyranosyl)-3,12-dioxo-15,16-epoxi-4α-hydroxycleroda-13(16),14-dieno and 3-oxo-4α,12-dihydroxy-14,15,16-trinorclerodan-13-oic acid. Four aromatic derivatives amides from ent-kaur-16-en-18-oic acid were prepared through nucleophilic substitutive reactions. The corresponding methyl esters from the ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid were also obtained. Two new derivatives from 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno were prepared through reduction reaction and another one by the biotransformation of diterpene, made by the fungus Rhizopus stolonifer. Some isolated compounds and derivatives were submited to cytotoxic activity using ovarian (OVCAR-8), glioblastoma (SF-295) and colon (HCT-116) cell lines, and the compounds ent-kaur-16-en-15-oxo-18-oic acid and ent-17(α-pinen-10â-yl)-15-oxokauran-18-oic acid registered activity during preliminaries assays. The secondary metabolites were isolated through usual chromatography techniques, using thin layer chromatography, column chromatography, size exclusion chromatography and high performance liquid chromatography. The determination of the structure of the isolated compounds was performed through physical (melting point and optical rotation) and spectrometric techniques, such infrared (IR), high resolution mass spectrometry and nuclear magnetic resonance (NMR), including bidimensional experiments, and comparison with literature data.
O presente trabalho relata o estudo quÃmico do caule e das raÃzes de Croton limae, coletado no municÃpio de AndaraÃ-BA. A investigaÃÃo fitoquÃmica do extrato etanÃlico do caule levou ao isolamento de dois diterpenos do tipo caurano, Ãcido ent-caur-16-en-18-oico e Ãcido ent-caur-16-en-15-oxo-18-oico, dois diterpenos do tipo clerodano, 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e Ãcido 3-oxo-4α-hidroxi-13,14,15,16-tetranorclerodan-12-oico, e do flavonoide 3-O-β-D-glicopiranosilquercetina. A investigaÃÃo do extrato hexÃnico das raÃzes levou ao isolamento de um triterpeno, Ãcido acetilaleuritÃlico, do dÃmero inÃdito Ãcido ent-17(α-pinen-10â-il)-15-oxocauran-18-oico, de dois novos diterpenos clerodanos, 3-oxo-15,16-epoxi-4α,12-dihidroxicleroda-13(16),14-dieno e 15,16-epoxi-3α,4α,12-trihidroxicleroda-13(16),14-dieno, um diterpeno do tipo halimano, 15,16-epoxi-3α,12-dihidroxihalima-5(10),13(16),14-trieno, e da mistura dos esteroides β-sitosterol e estigmasterol. Do extrato etanÃlico das raÃzes foram isolados dois flavonoides, 3-O-β-D-glicopiranosilcanferol e ombuina-3-O-β-rutinosÃdeo, e trÃs diterpenos clerodanos inÃditos, 3α,4α,15,16-tetrahidroxicleroda-13-eno, 6-(β-D-glicopiranosil)-3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e Ãcido 3-oxo-4α,12-dihidroxi-14,15,16-trinorclerodan-13-oico. Foram preparadas quatro amidas aromÃticas derivadas do Ãcido ent-caur-16-en-18-oico e os respectivos Ãsteres metÃlicos dos Ãcidos ent-caur-16-en-18-oico e ent-caur-16-en-15-oxo-18-oico. Foram preparados dois derivados reacionais obtidos atravÃs de reaÃÃes de reduÃÃo do diterpeno clerodano 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e outro atravÃs da biotransformaÃÃo deste diterpeno pelo fungo Rhizopus stolonifer. Alguns compostos isolados e derivados foram submetidos a testes de atividade citotÃxica, utilizando linhagens de cÃlulas tumorais de ovÃrio (OVCAR-8), glioblastoma (SF-295) e colÃn (HCT-116), onde testes preliminares indicaram que os compostos ent-caur-16-en-15-oxo-18-oico e Ãcido ent-17(α-pinen-10â-il)-15-oxocauran-18-oico apresentaram atividade. Os metabÃlitos secundÃrios foram isolados atravÃs de tÃcnicas cromatogrÃficas usuais, utilizando cromatografia em camada delgada, cromatografia em coluna, cromatografia por exclusÃo molecular e cromatografia lÃquida de alta eficiÃncia. A determinaÃÃo estrutural foi realizada atravÃs de mÃtodos fÃsicos (ponto de fusÃo e rotaÃÃo Ãptica) e do uso de tÃcnicas espectroscÃpicas e espectromÃtricas como infravermelho (IV), espectrometria de massas de alta resoluÃÃo e ressonÃncia magnÃtica nuclear de hidrogÃnio (RMN 1H) e carbono-13 (RMN 13C), incluindo experimentos bidimensionais, alÃm de comparaÃÃo com dados da literatura.
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Monteiro, Ariadne Santana e. Neves. "Efeito do diterpeno Manool sobre a função vascular de ratos normotensos e hipertensos." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/17/17137/tde-29082016-095825/.
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Introdução: A hipertensão arterial sistêmica (HAS) é uma condição clínica multifatorial caracterizada por níveis elevados e sustentados de pressão arterial. Nos últimos anos, estudos demonstraram o efeito cardiovascular de diversos metabólitos originados de várias espécies de plantas. O diterpeno é um exemplo, o qual age por meio de diversos mecanismos farmacológicos. Sabendo que o Manool pertence a esta classe de compostos, isso o torna uma substância com potencial uso no tratamento da HAS, motivo pelo qual se propôs o desenvolvimento deste trabalho. Objetivos: 1) Avaliar in vivo o possível efeito vasodilatador de diferentes doses do Manool e o efeito sobre os níveis plasmáticos de óxido nítrico (NO), em animais normotensos e hipertensos e; 2) Verificar in vitro os mecanismos endoteliais envolvidos na resposta de relaxamento, em anéis de aorta de ratos. Material e métodos: Os animais foram divididos aleatoriamente em dois grupos: hipertenso e normotenso. Os animais do grupo hipertenso foram submetidos ao procedimento cirúrgico 2R1C para indução de hipertensão, enquanto os animais do grupo normotenso foram sham-operados. A pressão arterial (PA) não-invasiva, foi mensurada utilizando-se um manguito, conectado a um sensor para registro de PA, colocado em torno da cauda do animal. Para identificar os efeitos in vivo do composto, três doses do composto foram aplicadas nos animais, a monitorização invasiva da PA foi realizada por meio do MP System 100 A. Para a medida do óxido nítrico (NO) plasmático, foi utilizada a técnica de quimiluminescência NO/ozônio (O3). Com intuito de observar os mecanismos envolvidos no relaxamento induzido pelo composto, curvas concentração-resposta para o Manool, foram obtidas em anéis de aorta com e sem endotélio, na presença e ausência de L-NAME e ODQ. Resultados: Os resultados sobre a ?PAS mostrou que o Manool, promoveu redução da PAS tanto em normotensos quanto hipertensos. Os resultados das curvas dose-resposta mostraram que o manool promoveu relaxamento Resumo dependente do endotélio e este foi inibido na presença de L-NAME e ODQ. Não foi observado diferença na dosagem de NOx. Conclusão: Em resposta aos objetivos propostos para a presente investigação pode-se concluir que o Manool é uma droga hipotensora, possivelmente dependente em grande parte da função endotelial via NO/cGMP.Introduction: Systemic hypertension (SH) is a multifactorial clinical condition characterized by high and sustained levels of blood pressure. In recent years, studies have demonstrated the cardiovascular effect of various metabolites derived from many plant species. The diterpene is an example, which acts through different pharmacological mechanisms. The Manool belongs to this class of compounds, that makes a substance with potential use in the treatment of SH, which let us to propose the development of this work. Objectives: 1) To evaluate in vivo the possible vasodilator effect of different doses of Manool and the effect on the plasma levels of nitric oxide (NO) in normotensive and hypertensive animals; 2) Evaluate in vitro endothelial mechanisms involved in the relaxation response in rat aortic rings. Material and methods: The animals were randomly divided in two groups: normotensive and hypertensive. The animals of the hypertensive group underwent the surgical procedure 2K1C for hypertension induction, while the animals of the normotensive group were sham-operated. The blood pressure (BP) non-invasive, was measured using a cuff, connected to a sensor for registration BP, placed around the animal\'s tail. To identify the in vivo effects of the compound, three doses of the compound were applied in animals, invasive BP monitoring was performed using the System MP 100 A. For the measurement of NO plasma, we used the technique of chemiluminescence NO/ozone (O3). In order to observe the mechanisms involved in the relaxation induced by compound concentration-response curves for Manool were obtained in the aorta rings with and without endothelium in the presence and absence of L-NAME and ODQ. Results: The results on variation of systolic blood pressure (?SBP) showed that Manool, decreases the SBP in both normotensive as hypertensive. The results of the dose-response curves showed that the Manool promoted endothelium dependent relaxation and this was inhibited in the presence of L-NAME and ODQ. There was no difference in NOx dosage. Conclusion: In response to the proposed Abstract objectives for the present investigation may conclude that the Manool is a hypotensive drug, possibly dependent in large part on endothelial function NO / cGMP pathway.
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Togashi, Ricardo Hideo. "Atividade biolÃgica das lectinas de sementes de erythrina fusca e velutina, de algas marinhas hypnea musciformes, bryothamnion seaforthii e triquetrum e do produto natural diterpeno casbano, em culturas de pseudomonas aeruginosa." Universidade Federal do CearÃ, 2010. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=5455.
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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃNeste trabalho avaliamos a atividade biolÃgica de lectinas de sementes de Erythrina fusca e velutina, de algas marinhas Hypnea musciformes, Bryothamnion seaforthii e triquetrum e do diterpeno casbano, um produto natural isolado de Croton nepetaefolius, sobre Pseudomonas aeruginosa ATCC 10145. Foi comparada a aÃÃo in vitro das 5 lectinas e do diterpeno casbano, sobre colÃnias de P. aeruginosa, em placas de poliestireno. Investigada a aÃÃo das lectinas de alga marinha H.musciforme, de sementes de Erythrina velutina, e do diterpeno casbano, no processo de formaÃÃo do biofilme bacteriano de P.aeruginosa, em placas de poliestireno; e identificado entre as lectinas de E.velutina, H.musciforme e diterpeno casbano, aquele com maior potencial de aplicaÃÃo no controle do crescimento de colÃnias de P. aeruginosa. As lectinas testadas nÃo foram capazes de inibir o crescimento e a formaÃÃo de biofilme de Pseudomonas aeruginosa nas condiÃÃes experimentadas. Por outro lado, diterpeno casbano, na concentraÃÃo de 500 μg/mL em 18 horas, foi capaz de inibir o crescimento de P. aeruginosa em 40%, comparado ao controle positivo. Esta inibiÃÃo foi observada atà uma concentraÃÃo de 125 μg/mL. Entretanto, nÃo foi observada inibiÃÃo da formaÃÃo do biofilme da P. aeruginosa nas concentraÃÃes utilizadas neste estudo.
In this study the biological activity of seeds lectins from Erythrina velutina and fusca, marine algae Hypnea musciformis, Bryothamnion seaforthii and triquetrum and the diterpene casbane, a natural product isolated from Croton nepetaefolius was evaluated upon Pseudomonas aeruginosa ATCC 10145. We compared the in vitro effect of lectins and diterpene casbane on colonies of P. aeruginosa in microtiter plates. Investigated the action of lectins from marine algae H. musciforme of seeds of Erythrina velutina, and diterpeno casbano in the process of formation of P. aeruginosa biofilm on polystyrene plates, and identified among lectins: E. velutina, H. musciforme and diterpene casbane, the one with greater potential for application in controlling the growth of colonies of P. aeruginosa. The lectins tested were able to inhibit growth and biofilm formation of P. aeruginosa in the studied conditions. Moreover, diterpene casbane at a concentration of 500 mg/mL in 18 hours, was able to inhibit the growth of P. aeruginosa in 40%, compared to positive control. This inhibition was observed until a concentration of 125 mg/mL. However, the inhibition of biofilm formation of P. aeruginosa there was no observed at the concentrations used in this study.
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Fazanaro, Fabiano. "AvaliaÃÃo in vitro da interferÃncia de lectinas vegetais e do diterpeno casbano isolado de Croton nepataefolius sobre o crescimento de formas planctÃnicas e biofilmes de Pseudomonas aeruginosa." Universidade Federal do CearÃ, 2010. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=5702.
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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃEste trabalho mostra as atividades biolÃgicas de lectinas isoladas de sementes de Vatairea macrocarpa e de Vatairea guianensis e do composto vegetal diterpeno casbano, isolado do Croton nepetaefolius, sobre o crescimento de Pseudomonas aeruginosa (ATCC 9027), causadora de otite externa. Comparou-se a aÃÃo in vitro das duas lectinas e do composto vegetal diterpeno casbano sobre culturas de P. aeruginosa em placas de poliestireno. As cÃlulas bacterianas foram testadas tanto em sua forma planctÃnica como na de biofilme. As lectinas testadas nÃo foram capazes de inibir o crescimento da forma planctÃnica e a formaÃÃo de biofilme da P. aeruginosa nas condiÃÃes experimentais. Por outro lado, o diterpeno casbano foi capaz de inibir o crescimento de P. aeruginosa na forma planctÃnica, nas concentraÃÃes de 500, 250 e 125 Âg/mL. Entretanto, nÃo foi observada inibiÃÃo da formaÃÃo do biofilme da P. aeruginosa nas concentraÃÃes utilizadas neste estudo. O diterpeno casbano isolado de Croton nepetaefolius poderà ser utilizado, apÃs a realizaÃÃo de outros estudos, como ferramenta biotecnolÃgica antimicrobiana sobre as formas planctÃnicas de P. aeruginosa
This work shows the biological activities of lectins isolated from Vatairea macrocarpa and Vatairea guianensis seeds and the vegetable compound diterpen casban, isolated from Croton nepetaefolius on the growth of Pseudomonas aeruginosa (ATCC 9027) that causes otites externa. The in vitro activity of the two lectins and vegetable compound casbane diterpene were compared on cultures of P. aeruginosa in polystyrene microplates. The bacterial cells were tested such in planktonic as in biofilm forms. The lectins tested were not capable to inhibit the growth and biofilm production of P. aeruginosa in the experimental conditions. On the other hand, the casbane diterpene was capable to inhibit the growth of planctonic forms of P. aeruginosa at the concentrations of 500, 250 and 125 Âg/mL. However, the inhibition of biofilm production was not observed at the same concentrations. The casbane diterpene isolated from Croton nepetaefolius can be used, after the realization of other studies, as an antibiotic biotechnological tool on planktonic forms of P. aeruginosa
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Simplicio, Janaina Aparecida. "Avaliação do efeito cardiovascular do labdano ácido ent-3-acetóxi-labda-8(17),13-dieno-15-óico." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/17/17133/tde-27082013-180939/.
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A pesquisa e o uso de produtos naturais como agentes terapêuticos tem crescido muito nos últimos anos. Os diterpenos são os principais constituintes de extratos de plantas que são usadas na medicina popular no tratamento da hipertensão arterial. Diterpenos da classe dos labdanos exercem atividade inibitória sobre a contração vascular e induzem relaxamento desses tecidos. Nesse sentido, o presente estudo foi delineado de forma a investigar os mecanismos envolvidos no efeito cardiovascular do labdano ácido ent-3-acetóxi-labda-8(17),13-dieno-15-óico (labda-15-óico) em ratos. Os resultados mostraram que o labdano exerce seu efeito inibitório máximo sobre a contração vascular induzida pelo KCl após 30 min de incubação. O efeito inibitório do labda-15-óico sobre a contração induzida por KCl foi totalmente revertido 60 e 120 minutos após a remoção do diterpeno das preparações em anéis sem endotélio (E-) e com endotélio (E+), respectivamente. Os valores de Emax para as curvas de fenilefrina e serotonina foram reduzidos na presença do labda-15-óico em anéis de aorta de rato E+ e E-. O labda-15-óico reduziu a contração induzida pelo CaCl2 em anéis E- nas concentrações de 10, 50 e 100 mol/L. O labda-15-óico não alterou a mobilização do Ca2+ intracelular induzida por fenilefrina ou cafeína. O labdano induziu relaxamento em artérias aorta E+ ou E- pré-contraídas com fenilefrina ou KCl. Em anéis de aorta E+ pré-contraídos com fenilefrina, os valores de Emax para o relaxamento foram reduzidos na presença de L-NAME, ODQ, hemoglobina, 7-nitroindazol, Rp-8-Br-Pet, tapsigargina e tetraetilamônio. Por outro lado, indometacina, wortmanin, LY294002, H-89, SQ22,536, atropina e propranolol não afetaram o relaxamento induzido pelo labdano. O labdano aumentou os níveis de nitrato e GMPc em anéis E+, mas não alterou os níveis de AMPc. O composto em estudo elevou ainda, a intensidade de fluorescência emitida por amostras de células endoteliais marcadas com DAF-2DA, indicando um aumento dos níveis de NO citosólico. Além disso, o labda-15-óico (3 mg/Kg) induziu hipotensão em ratos não anesteziados. O L-NAME reduziu a resposta hipotensora induzida pelo labdano. Concluímos que o labdano exerce um efeito vasorelaxante in vitro e hipotensor in vivo. O labda-15-óico age no músculo liso vascular, onde bloqueia canais para Ca2+ sensíveis a voltagem e operados por receptores, levando à redução do influxo de Ca2+ extracelular. A resposta de relaxamento é parcialmente dependente do endotélio onde o labda-15-óico ativa a via de sinalização do NO-GMPc e promove abertura de canais para K+ no músculo liso vascular. Os estudos in vivo confirmam a participação do NO na resposta cardiovascular induzida pelo labda-15-óico.The research, development and use of natural compounds as therapeutic agents have been increasing in recent years. Diterpenoids are the main constituents of plant extracts that are used in folk medicine for the treatment of hypertension. Labdane-type diterpenes are described to exert antispasmodic and relaxant action in vascular tissues. The present investigation aimed to evaluate the mechanisms (in vitro and in vivo) underlying the cardiovascular effects displayed by the labdane ent-3-acetoxy-labda-8(17),13-dien-15-oic acid (labda-15-oic) in rats. Our findings show that labda-15-oic achieved its maximal inhibitory action on KCl-induced contraction at 30 min. The inhibitory effect on the the contraction induced KCl elicided by labda-15-oic was totally abolished 60 and 120 min after the removal of the labdane from the medium bath in endothelium-denuded (E-) rings and endothelium-intact (E+) rings. The Emax values for phenylephrine and serotonin in E+ and E- rings were reduced in the presence of labda-15-oic. The labda-15-oic inhibited the contraction induced CaCl2 in E- rings at 10, 50 and 100 mol/L. The labdane did not alter the intracellular Ca2+ mobilization induced by phenylephrine or caffeine. The labdane induced relaxation in E+ and E- rings pre-contracted with phenylephrine or KCl. In E+ rings pre-contracted with phenylephrine, labda-15-oic-induced relaxation was reduced in the presence of L-NAME, ODQ, haemoglobin and RP-8-Br-Pet. On the other hand, indomethacin, wortmannin, LY294002, H-89, SQ22,536, atropine, propranolol did not have a significant effect on the relaxation induced by the labdane. The labdane increased the levels of cGMP and nitrate but not cAMP in E+ rings. The compound studied also increased the intensity of fluorescence emitted by samples of endothelial cells labeled with DAF-2DA indicating an increase in the cytosolic levels of NO. Furthermore, labda-15-oic (3 mg/Kg) induced hypotension in unanesthezided rats and this effect was attenuated by L-NAME. Taken together, our results demonstrate that the labdane exerts a vasorelaxant effect in vitro and hypotensive effect in vivo. The labda-15-oic acts on vascular smooth muscle where it blocks Ca2+ influx through interference with both voltage and receptor-operated channels. The relaxant action of the labdane is also partly mediated by the activation of endothelial NO-cGMP pathway and the opening of K+ channels present in vascular smooth muscle. The studies in vivo confirm the role of NO in the cardiovascular response induced labda-15-oic acid.
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Cavalcanti, Bruno CoÃlho. "AvaliaÃÃo do potencial genotÃxico e mutagÃnico do Ãcido caurenÃico, um diterpeno isolado da planta Copaifera langsdorffi Desf. (LEGUMINOSAE)." Universidade Federal do CearÃ, 2006. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1400.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoFundaÃÃo de Amparo à Pesquisa do Estado do CearÃ
Kaurenoic acid (KA) is a diterpene presents in the oil-resin (copaiba oil) from plants belongs to Copaifera spp. As copaiba oil, KA also displayed a great variability of medicinal applications. In the present study, the genotoxic and mutagenic potential of KA from Copaifera langsdorffii on human lymphocytes, human leukemia cells (HL60) and bone marrow cells was evaluated. KA did not show selective action between lymphocytes and leukemia cells, has been induced apoptosis and DNA damage at same magnitude as valuated by bromide etidium/orange acridine and comet assay. Due to this observation, lymphocytes were selected for further experiments. According with comet assay results, more than 80% of lymphocytes DNA damage was repaired after 48 hours post-treatment. Lymphocytes treated with KA (30 and 60Âg/mL) showed increases on micronucleus frequencies in relation to negative control group. On the chromosome aberration test, lymphocytes treated at phse G1 and transition phase G1/S showed great sensibility (cytotoxicity and chromosomes aberrations) in comparison to cells treated at another phases of cell cycle. After treatment, any increase of polyploidy cells number was noted. Mices were treated with KA (25, 50 and 100mg/kg), and after 24 and 48 hours, they were sacrificed afterwards with the medulla extraction. This material was submitted to chromosomal damage observations (microniclei) in polychromatic erythrocytes (PCE). A great occurrence of micronucleated PCE was noted only at animals groups sacrificed 24 hours after treatment. The rate between PCE and NCE (normochromatic erythrocytes) was lower for animals sacrificed later. These observations indicating toxicity effects on the bone marrow cells. The mutagenic assay with yeast Saccharomyces cereviseae showed that the cytotoxic and mutagenic effects of KA were more pronounced during exponential growth phase, when the access to DNA is facilitated. KA induced locus and frameshift mutations. Frameshift mutations induced by DNA-intercalanting drugs have been correlated with DNA strand breaks induced by inhibition of DNA topoisomerases. On the DNA relaxation assay, KA inhibited the action of topoisomerase I. This inhibition effect seens to be related to the intercalanting ability of kaurenoic acid between DNA bases of pair. Thus, DNA strand breaks, the occurrence of micronucleated cells and frameshift mutations could be explained by the intercalanting action of kaurenoic acid. And the absence of polyploidy cells suggests that kaurenoic acid did not interfere on mitotic apparatus of cell. In conclusion, kaurenoic acid showed genotoxic and mutagenic effects on all the assays used
O Ãcido caurenÃico (AC) à um diterpeno presente no Ãleo resinoso de espÃcies de Copaifera. Assim como o Ãleo resinoso, o AC tambÃm apresenta uma ampla variabilidade de aplicaÃÃes medicinais. O presente trabalho teve como objetivo avaliar o potencial genotÃxico e mutagÃnico do AC isolado da planta Copaifera langsdorffii em linfÃcitos, cÃlulas leucÃmicas HL60 e em cÃlulas da medula Ãssea de camundongos. O AC nÃo mostrou seletividade entre linfÃcitos e HL60 tendo induzido apotose e danos ao DNA na mesma intensidade, avaliados pela coloraÃÃo diferencial por brometo de etÃdio/acridina laranja e pelo teste do cometa, respectivamente. De acordo com o teste do cometa, mais de 80% dos danos induzidos ao DNA de linfÃcitos foi reparada 48 horas apÃs o tratamento. LinfÃcitos tratados com AC apresentaram aumento, siginificativo, na freqÃÃncia de micronÃcleos e maior sensibilidade (citotoxicidade e aberraÃÃes cromossÃmicas) nas fases G1 e G1/S do ciclo celular, sem induzir aumento no nÃmero de cÃlulas poliplÃides. Camundongos foram tratados com AC nas doses de 25, 50 e 100mg/kg e apÃs 24 e 48 horas sacrificados, sendo, posteriormente, extraÃda a medula Ãssea, e o material submetido Ãs observaÃÃes de perdas cromossÃmicas (micronÃcleos) em eritrÃcitos policromÃticos. Uma maior incidÃncia de micronÃcleos ocorreu no grupo de animais sacrificados 24 horas apÃs o tratamento. A avaliaÃÃo da razÃo entre eritrÃcitos policromÃticos e normocromÃticos, foi menor para os animais sacrificados 48 horas apÃs o tratamento, indicando toxicidade em cÃlulas da medula. Nos ensaios de mutagÃnese com a levedura Saccharomyces cerevisea, o efeito citotÃxico e mutagÃnico do AC foi mais acentuado durante o crescimento exponencial da levedura, no qual o DNA està mais acessÃvel ao composto. O AC induziu mutaÃÃes lÃcus especÃficas e de deslocamento do quadro de leitura. MutaÃÃes do tipo deslocamento do quadro de leitura tendem a serem induzidas por agentes intercalantes de DNA e tÃm sido correlacionadas com as quebras de fitas de cadeia de DNA induzidas pela inibiÃÃo da aÃÃo de topoisomerase. No teste de relaxamento do DNA, o AC inibiu a aÃÃo da topoisomerase I. A inibiÃÃo da aÃÃo da topoisomerase I parece estar relacionada à intercalaÃÃo do AC no DNA. Assim, as quebras de fitas no DNA e induÃÃo de micronÃcleos e mutaÃÃes de deslocamento do quadro de leitura, podem estar relacionadas à aÃÃo intercalante do Ãcido caurenÃico. A ausÃncia de cÃlulas poliplÃides sugere que o Ãcido caurenÃico nÃo interfere no aparelho mitÃtico da cÃlula. Em conclusÃo, o Ãcido caurenÃico apresenta potencial genotÃxico e mutagÃnico nos modelos estudados.
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Matos, Dalyara Mendonça de. "Determinação do perfil farmacocinético e da biodisponibilidade sistêmica do ácido caurenoico em ratos." Universidade Federal de Juiz de Fora (UFJF), 2016. https://repositorio.ufjf.br/jspui/handle/ufjf/5627.
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O ácido caurenoico é um diterpeno caurânico encontrado em diversas espécies vegetais tais como Mikania glomerata (guaco), Copaifera langsdorffi (copaíba) e Smallanthus sonchifolia (yacon). Essa substância apresenta ação tripanocida, larvicida, antimicrobiana, analgésica, anti-inflamatória, relaxante da musculatura lisa, hipotensora, diurética, hipoglicêmica e citotóxica. Por tratar-se de uma molécula promissora para o desenvolvimento de novos fármacos, o objetivo de nosso estudo é determinar o perfil farmacocinético e a biodisponibilidade oral do ácido caurenoico em ratos. Foram utilizados Ratos Wistar (n=6), aos quais foram administrados 50 ou 100 mg/kg de ácido caurenóico por via IV ou oral. Os animais foram canulados pela veia jugular, permitindo a administração intravenosa do ácido caurenoico e coletas seriadas de sangue do tempo zero até 10 horas. A extração do ácido caurenoico do plasma foi realizada após acidificação com ácido acético 1% (v/v), seguida de precipitação de proteínas com acetonitrila. A quantificação do analito foi realizada utilizandose cromatografia líquida de alta eficiência com detecção ultravioleta (CLAE-UV), empregando-se as seguintes condições analíticas: coluna C18 (150 x 4.6 mm, 5 μm) mantida a 40°C, eluição isocrática com fase móvel composta por acetonitrila:água acidificada com ácido ortofosfórico 0,1% (70:30 v/v), fluxo de 1 mL/min, detecção em 200 nm e volume de injeção de 80 μL. A metodologia proposta foi validada e mostrou-se precisa, exata, robusta, confiável e linear entre 0,75 e 100 μg/mL. A partir do decaimento plasmático dos animais que receberam 50 mg/kg do ácido caurenoico por via intravenosa, foram determinados os seguintes parâmetros farmacocinéticos: Cmax = 22,2 ± 1,6 mg/L, Vd = 14,5 ± 1,5 L/kg, CL = 17,7 ± 1,5 mL/min/kg, ASC = 2859 ± 278 mg/L.h e T1/2 = 9,5 ± 0.6 h. Os resultados obtidos apontaram que o ácido caurenoico, administrado por via intravenosa, apresentou um comportamento cinético linear e bicompartimental na dose testada. Não foram encontrados níveis quantificáveis da substância nas amostras provenientes de ratos tratados com 50 ou 100 mg/kg de ácido caurenoico, por via oral, impossibilitando a definição de sua biodisponibilidade oral e sugerindo uma baixa absorção por esta via. Este é o primeiro estudo farmacocinético desta molécula e, esta avaliação, mesmo que pré-clínica, pode contribuir para o processo de desenvolvimento de novos medicamentos a partir desse diterpeno.
Kaurenoic acid is a kaurane-type diterpene found in several plant species such as Mikania glomerata (guaco), Copaifera langsdorffi (copaíba) and Smallanthus sonchifolia (yacon). Previous studies described several biological activities for this substance such as antitrypanosomal, antimicrobial, analgesic, anti-inflammatory, smooth muscle relaxant, hypotensive, diuretic, hypoglycemic and cytotoxic. As this molecule represents a lead compound for the development of new drugs, the aim of our study is to determine the pharmacokinetics profile and oral bioavailability of kaurenoic acid in rats. Wistar rats (n = 6) received 50 or 100 mg/kg of kaurenoic acid by intravenous or oral routes. The insertion of a cannula into the right external jugular vein of Wistar rats allowed intravenous administration of kaurenoic acid and collection of blood samples within predetermined time intervals. Extraction procedures from plasma consisted of acidification with 1% acetic acid (v/v), followed by precipitation of proteins with acetonitrile. The supernatant was submitted to highperformance liquid chromatography with UV detection (HPLC-UV) for quantification of kaurenoic acid. The established analytical conditions were: C18 column (150 x 4.6 mm, 5 μm) maintained at 40 ° C, isocratic elution with a mobile phase consisting of acetonitrile: acidified water with 0.1% orthophosphoric acid (70:30 v/v), a flow of 1 mL/min, UV detection at 200 nm and injection volume of 80 μL. The proposed methodology proved to be precise, accurate, robust and reliable. The linearity range is between 0.75 and 100 μg/mL. Plasma decay of animals receiving an intravenously dose of 50 mg/kg allowed the determination of the following pharmacokinetic parameters: Cmax = 22.2 ± 1.6 mg/L; Vd = 14.5 ± 1.5 L/kg; CL = 17.7 ± 1.5 mL/min/kg; AUC = 2859 ± 278 mg/L.h and T1/2 = 9.5 ± 0.6 h. Kaurenoic acid administered intravenously showed a linear and two-compartment kinetic behavior at the tested dose. As no measurable levels of substance were found in the samples from mice treated orally with kaurenoic acid, the determination of oral bioavailability was not possible, suggesting poor absorption through this route. This is the first pharmacokinetic study of this molecule and this preclinical assessment can contribute to the process of development of new drugs with this diterpene.
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Vasconcelos, Mayron Alves de. "Atividade de lectinas e metabÃlitos bioativos de plantas sobre biofilmes microbianos de interesse clÃnico." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=11809.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorBiofilmes sÃo comunidades microbianas que encontram-se irreversivelmente associadas a uma superfÃcie e estÃo inseridas em uma matriz polimÃrica produzida por elas mesmas. Os biofilmes estÃo comumente relacionados a infecÃÃes nosocomiais que apresentam maior resistÃncia a agentes antimicrobianos quando comparadas com cÃlulas planctÃnicas, dificultando assim seus tratamentos e limitando as opÃÃes terapÃuticas. Nesse sentido a busca por novas molÃculas com aÃÃo antimicrobiana e antibiofilme tornou-se uma Ãrea ativa na pesquisa cientÃfica. Os vegetais sÃo fontes de uma variedade de molÃculas com propriedades antimicrobianas, dentre estas podemos citar as lectinas e os metabÃlitos secundÃrios. Diversos estudos tÃm relatado a aÃÃo antimicrobiana e antibiofilme dessas classes de molÃculas como forma alternativa ao uso de antibiÃticos. Assim, o objetivo desse trabalho foi avaliar a aÃÃo antimicrobiana e antibiofilme de diversas lectinas isoladas de leguminosas e algas, bem como de dois metabÃlitos secundÃrios isolados de plantas, derriotusona A (isolado de Lonchocarpus obtusus) e diterpeno casbano (isolado de Croton nepetaefolius). Os resultados demonstraram que algumas das lectinas testadas foram capazes de inibir o crescimento planctÃnico e/ou a formaÃÃo de biofilme de determinados micro-organismos. A lectina isolada de Vaitarea macrocarpa (VML) mostrou ser a lectina mais promissora, mostrando forte aÃÃo sobre o crescimento planctÃnico e formaÃÃo de biofilmes de Staphylococcus aures e Staphylococcus epidermidis. Derriobstusona A mostrou uma potencial aÃÃo antibacteriana e antibiofilme sobre S. aureus, enquanto que, Escherichia coli apresentou menor sensibilidade ao composto. Em adiÃÃo, derriotusona A demonstrou uma potencial aÃÃo antioxidante. Em relaÃÃo ao diterpeno casbano, em geral o composto foi capaz de inibir o crescimento planctÃnico, formaÃÃo de biofilmes e causar danos nos biofilmes prÃ-formados de S.aures, S. epidermidis, Candida albicans e Candida glabrata, e mostrou ainda ser efetivo contra biofilmes formados pela associaÃÃo entre estas bactÃrias e leveduras. Em conclusÃo, os resultados mostraram que algumas lectinas, assim como os metabÃlitos secundÃrios utilizados nesse estudo, podem ser consideradas potenciais agentes antimicrobianas e antibiofilmes, sugerindo assim o uso dessas molÃculas no tratamento de infecÃÃes associadas a diferentes micro-organismos.
Biofilms are microbial communities that are irreversibly attached to a surface and are embedded in a polymeric matrix produced by them. Biofilms are commonly related to nosocomial infections that showing an enhanced resistance to antimicrobial agents compared to planktonic cells, thus hindering their treatments and limiting therapeutic options. In this context, the search for new molecules with antimicrobial and antibiofilm action has become an active area of research. The plants are sources of a variety of molecules with antimicrobial properties, among them we can mention the lectins and secondary metabolites. Several studies have reported the antimicrobial and antibiofilm action of these molecules classes as an alternative to antibiotics. Thus, the aim of this study was to evaluate the antimicrobial and antibiofilm of various lectins isolated from leguminous and algae, as well as two secondary metabolites isolated from plants , derriotusone A (isolated from Lonchocarpus obtusus) and casbane diterpene (isolated from Croton nepetaefolius). The results showed that some lectins tested were able to inhibit the planktonic growth and/or the biofilm formation of certain microorganisms. The lectin isolated from Vaitarea macrocarpa (VML) showed to be the most promising lectin, showing strong action on the planktonic growth and biofilm formation of Staphylococcus aures and Staphylococcus epidermidis. The derriobstusone A showed potential antibacterial and antibiofilm activite on S. aureus, whereas Escherichia coli showed lower sensitivity to the compound. In addition, derriotusone showed a potential antioxidant activity. Regarding to casbane diterpene, in general the compound was able to inhibit planktonic growth, formation of biofilms and disrupt the preformed biofilms of the S.aures, S. epidermidis, Candida albicans and Candida glabrata, and also showed to be effective against biofilms formed by the association between these bacteria and yeasts. In conclusion, the results showed that some lectins, as the secondary metabolites used in this study, may be considered as potential antimicrobial and antibiofilm agents, thus suggesting the use of these molecules in the treatment of infections associated with different microorganisms.
Books on the topic "Diterpeni"
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Seaman, Fred, Ferdinand Bohlmann, Christa Zdero, and Tom J. Mabry. Diterpenes of Flowering Plants. New York, NY: Springer New York, 1990. http://dx.doi.org/10.1007/978-1-4612-3274-2.
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F, Seaman, ed. Diterpenes of flowering plants: Compositae (Asteraceae). New York: Springer-Verlag, 1990.
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Zinkel, Duane F. Diterpene resin acids from the needle oleoresin of pinus strobus. [Madison, WI?: U.S. Forest Service, Forest Products Laboratory, 1987.
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Barton, D. H. R., J. R. Hanson, and R. A. Raphael. Tetracyclic Diterpenes. Elsevier Science & Technology Books, 2013.
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Rahman, A. U. Diterpenoid and Steroidal Alkaloids. Elsevier, 1990.
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Hong, Bor-Cherng. Synthesis of biologically active ingenol analogues via intramolecular photocycloaddition of dioxenones. 1993.
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Diterpenes of Flowering Plants: Compositae. Springer, 2014.
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Mabry, Tom J., Fred Seaman, Ferdinand Bohlmann, and Christa Zdero. Diterpenes of Flowering Plants: Compositae. Springer London, Limited, 2012.
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Mabry, Tom J., Fred Seaman, Ferdinand Bohlmann, and Christa Zdero. Diterpenes of Flowering Plants: Compositae. Springer, 2011.
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Bohlmann, F., T. J. Mabry, F. Seaman, and C. Zdero. Diterpenes of Flowering Plants: Composite, Asteraceae. Springer, 1990.
Find full textBook chapters on the topic "Diterpeni"
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Breitmaier, Eberhard. "Diterpene." In Terpene, 60–89. Wiesbaden: Vieweg+Teubner Verlag, 1999. http://dx.doi.org/10.1007/978-3-322-94727-7_4.
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Barriault, Louis. "Diterpenes." In From Biosynthesis to Total Synthesis, 279–95. Hoboken, NJ: John Wiley & Sons, Inc, 2016. http://dx.doi.org/10.1002/9781118754085.ch8.
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Seaman, Fred, Ferdinand Bohlmann, Christa Zdero, and Tom J. Mabry. "Diterpene Distribution: Compositae." In Diterpenes of Flowering Plants, 431–84. New York, NY: Springer New York, 1990. http://dx.doi.org/10.1007/978-1-4612-3274-2_4.
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Ramakrishna, Akula, and Gokare Aswathanarayana Ravishankar. "Diterpene Sweeteners (Steviosides)." In Natural Products, 3193–203. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-22144-6_137.
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Thomson, R. H. "Diterpenoid quinones." In Naturally Occurring Quinones IV, 650–710. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-009-1551-0_6.
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Hegazy, Mohamed-Elamir F., Tarik A. Mohamed, Abdelsamed I. Elshamy, Ahmed R. Hamed, Sara Abdelfatah, Soleiman E. Helaly, Nahla S. Abdel-Azim, et al. "Tanshinone Diterpenes." In Natural Medicines, 65–85. Boca Raton : Taylor & Francis, [2019]: CRC Press, 2019. http://dx.doi.org/10.1201/9781315187853-4.
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Atta-ur-Rahman and Viqar Uddin Ahmad. "Miscellaneous Diterpenes." In 13C-NMR of Natural Products, 622–80. Boston, MA: Springer US, 1992. http://dx.doi.org/10.1007/978-1-4615-3288-0_69.
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Seigler, David S. "Diterpenes and Sesterterpenes." In Plant Secondary Metabolism, 398–426. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-4913-0_22.
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Speer, K., A. Hruschka, T. Kurzrock, and I. Kölling-Speer. "Diterpenes in Coffee." In ACS Symposium Series, 241–51. Washington, DC: American Chemical Society, 2000. http://dx.doi.org/10.1021/bk-2000-0754.ch025.
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Seaman, Fred, Ferdinand Bohlmann, Christa Zdero, and Tom J. Mabry. "Introduction." In Diterpenes of Flowering Plants, 1–2. New York, NY: Springer New York, 1990. http://dx.doi.org/10.1007/978-1-4612-3274-2_1.
Full textConference papers on the topic "Diterpeni"
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Yunusov, M. S., E. M. Tsyrlina, S. A. Kryzhanovsky, I. B. Tsorin, and S. G. Yunusova. "ANTIARRHYTHMICS BASED ON DITERPENOID ALKALOIDS." In MedChem-Russia 2021. 5-я Российская конференция по медицинской химии с международным участием «МедХим-Россия 2021». Издательство Волгоградского государственного медицинского университета, 2021. http://dx.doi.org/10.19163/medchemrussia2021-2021-133.
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Kúsz, N., G. Sátori, A. Kincses, G. Spengler, Z. Barina, J. Hohmann, and D. Rédei. "Novel MDR-modulating Diterpenes from Euphorbia taurinensis." In GA 2017 – Book of Abstracts. Georg Thieme Verlag KG, 2017. http://dx.doi.org/10.1055/s-0037-1608146.
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Rijo, Patrícia. "Self-assembly nanoparticles of natural bioactive abietane diterpenes." In 7th International Electronic Conference on Medicinal Chemistry. Basel, Switzerland: MDPI, 2021. http://dx.doi.org/10.3390/ecmc2021-11351.
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Yamamura, Yoshimi. "Identification of key genes involved in scopadulane-type diterpene biosynthesis in Scoparia dulcis." In ASPB PLANT BIOLOGY 2020. USA: ASPB, 2020. http://dx.doi.org/10.46678/pb.20.107440.
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Sass, Daiane Cristina, Vladimir C. G. Heleno, Aline Nazaré Silva, Simone Cavalcante Silva, and Mauricio Gomes Constantino. "Synthesis of Pimarane-type Diterpenes from Constituents of Copaiba Oil." In 14th Brazilian Meeting on Organic Synthesis. São Paulo: Editora Edgard Blücher, 2013. http://dx.doi.org/10.5151/chempro-14bmos-r0132-2.
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Ribeiro, V., L. Oliveira, M. Santos, and S. Ambrósio. "Biotransformation of diterpenes from Brazilian Brown Propolis by Cunninghamella echinulata." In GA – 70th Annual Meeting 2022. Georg Thieme Verlag KG, 2022. http://dx.doi.org/10.1055/s-0042-1759256.
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Sousa, IP, MASC Chellegatti, RCS Veneziani, SR Ambrósio, and NAJC Furtado. "Biotransformation of diterpenes from Copaifera sp. oleoresins using filamentous fungi." In GA 2017 – Book of Abstracts. Georg Thieme Verlag KG, 2017. http://dx.doi.org/10.1055/s-0037-1608310.
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Pfeifer Barbosa, AL, A. Wenzel-Storjohann, JD Barbosa, C. Zidorn, C. Peifer, D. Tasdemir, and SS Ҫiçek. "Antimicrobial and cytotoxic properties of the Copaifera reticulata oleoresin and its major diterpene acids." In 67th International Congress and Annual Meeting of the Society for Medicinal Plant and Natural Product Research (GA) in cooperation with the French Society of Pharmacognosy AFERP. © Georg Thieme Verlag KG, 2019. http://dx.doi.org/10.1055/s-0039-3400134.
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Ҫiçek, SS, Barbosa AL Pfeifer, and U. Girreser. "Quantification of diterpene acids in copaiba oleoresin by UHPLC-ELSD and heteronuclear two-dimensional qNMR." In 67th International Congress and Annual Meeting of the Society for Medicinal Plant and Natural Product Research (GA) in cooperation with the French Society of Pharmacognosy AFERP. © Georg Thieme Verlag KG, 2019. http://dx.doi.org/10.1055/s-0039-3399704.
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Khusnutdinova, Nailya, Svetlana Meshcheryakova, and Rimma Sultanova. "The study of the antioxidant activity of 2-aminothiazoles containing a diterpene fragment by chemiluminescence." In MODERN SYNTHETIC METHODOLOGIES FOR CREATING DRUGS AND FUNCTIONAL MATERIALS (MOSM2020): PROCEEDINGS OF THE IV INTERNATIONAL CONFERENCE. AIP Publishing, 2021. http://dx.doi.org/10.1063/5.0068421.
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