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Reinhard Jetter - One of the best experts on this subject based on the ideXlab platform.
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oxidosqualene cyclases involved in the biosynthesis of Triterpenoids in quercus suber cork
Scientific Reports, 2020Co-Authors: Lucas Busta, Olga Serra, Ok Tae Kim, Marisa Molinas, Irene Perefossoul, Merce Figueras, Reinhard JetterAbstract:Cork is a water-impermeable, suberin-based material harboring lignin, (hemi)cellulose, and extractable small molecules (primarily Triterpenoids). Extractables strongly influence the properties of suberin-based materials. Though these previous findings suggest a key role for Triterpenoids in cork material quality, directly testing this idea is hindered in part because it is not known which genes control cork triterpenoid biosynthesis. Here, we used gas chromatography and mass spectrometry to determine that the majority (>85%) of non-polar extractables from cork were pentacyclic Triterpenoids, primarily betulinic acid, friedelin, and hydroxy-friedelin. In other plants, Triterpenoids are generated by oxidosqualene cyclases (OSCs). Accordingly, we mined Quercus suber EST libraries for OSC fragments to use in a RACE PCR-based approach and cloned three full-length OSC transcripts from cork (QsOSC1-3). Heterologous expression in Saccharomyces cerevisiae revealed that QsOSC1-3 respectively encoded enzymes with lupeol synthase, mixed α- and β-amyrin synthase, and mixed β-amyrin and friedelin synthase activities. These activities together account for the backbone structures of the major cork Triterpenoids. Finally, we analyzed the sequences of QsOSC1-3 and other plant OSCs to identify residues associated with specific OSC activities, then combined this with analyses of Q. suber transcriptomic and genomic data to evaluate potential redundancies in cork triterpenoid biosynthesis.
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composition of the epicuticular and intracuticular wax layers on kalanchoe daigremontiana hamet et perr de la bathie leaves
Phytochemistry, 2009Co-Authors: Clare Van Maarseveen, Reinhard JetterAbstract:Abstract Epicuticular and intracuticular waxes from both adaxial and abaxial surfaces of the leaves of Kalanchoe daigremontiana were analyzed. All wax mixtures were found to contain approximately equal amounts of Triterpenoids and very long chain fatty acid (VLCFA) derivatives. The triterpenoid fraction consisted of glutinol (8–19% of the total wax) and friedelin (4–9%), together with smaller amounts of glutanol, glutinol acetate, epifriedelanol, germanicol and β-amyrin. The VLCFA derivatives comprised C 27 –C 35 alkanes (19–37% of the total wax), C 32 –C 34 aldehydes (3–7%), C 32 and C 34 fatty acids (0.2–3%), C 26 –C 36 primary alcohols (4–8%), and C 42 –C 52 alkyl esters (2–9%). The wax layers were found to differ in triterpenoid amounts, with the intracuticular wax containing higher percentages of most Triterpenoids than the epicuticular wax. Friedelin, the only triterpenoid ketone present, showed the opposite distribution with higher proportions in the epicuticular wax. VLCFA derivatives also accumulated to higher percentages in the epicuticular than in the intracuticular wax layer. Epicuticular wax crystals were observed on both the adaxial and abaxial leaf surfaces.
Mondher El Jaziri - One of the best experts on this subject based on the ideXlab platform.
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comparative analysis of active constituents in centella asiatica samples from madagascar application for ex situ conservation and clonal propagation
Fitoterapia, 2007Co-Authors: Denis Randriamampionona, Billo Diallo, Francisco Rakotoniriana, Christian Rabemanantsoa, Kiban Cheuk, Annemarie Corbisier, Jacques Mahillon, Suzanne Ratsimamanga, Mondher El JaziriAbstract:A comparative quantitative analysis of the active Triterpenoids in Centella asiatica samples collected in different locations in Madagascar was carried out to evaluate the natural variability in triterpenoid content and to select elite samples for further ex situ germplasm conservation and clonal propagation. The highest asiaticoside content (6.42%) was measured in samples collected in Mangoro region. In vitro propagation of C. asiatica was successfully achieved in hormone-free medium. Although lower asiaticoside content was detected in 8-week-old vitro plants, the Mangoro sample still showed the highest content in this triterpenoid constituent (1.78%). Acetoxycentellynol, a C(15)-polyacetylene, was found to be accumulated up to 18 times more in in vitro plants as compared to plant material collected in situ.
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comparative analysis of active constituents in centella asiatica samples from madagascar application for ex situ conservation and clonal propagation
Fitoterapia, 2007Co-Authors: Denis Randriamampionona, Billo Diallo, Francisco Rakotoniriana, Christian Rabemanantsoa, Kiban Cheuk, Annemarie Corbisier, Jacques Mahillon, Suzanne Ratsimamanga, Mondher El JaziriAbstract:A comparative quantitative analysis of the active Triterpenoids in Centella asiatica samples collected in different locations in Madagascar was carried out to evaluate the natural variability in triterpenoid content and to select elite samples for further ex situ germplasm conservation and clonal propagation. The highest asiaticoside content (6.42%) was measured in samples collected in Mangoro region. In vitro propagation of C asiatica was successfully achieved in hormone-tree medium. Although lower asiaticoside content was detected in 8-week-old vitro plants, the Mangoro sample still showed the highest content in this triterpenoid constituent (1.78%). Acetoxycentellynol, a C-15-polyacetylene, was found to be accumulated up to 18 times more in in vitro plants as compared to plant material collected in situ. (c) 2007 Elsevier B.V All rights reserved.
Karen T Liby - One of the best experts on this subject based on the ideXlab platform.
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Triterpenoids cddo methyl ester or cddo ethyl amide and rexinoids lg100268 or nrx194204 for prevention and treatment of lung cancer in mice
Cancer Prevention Research, 2009Co-Authors: Karen T Liby, Mark M Yore, Renee Risingsong, Charlotte R Williams, Darlene B Royce, Michael B SpornAbstract:We tested members of two noncytotoxic classes of drugs, synthetic oleanane Triterpenoids and rexinoids, both as individual agents and in combination, for the prevention and treatment of carcinogenesis in a highly relevant animal model of lung cancer. Lung adenocarcinomas were induced in A/J mice by injection of the carcinogen vinyl carbamate. Mice were fed drugs in diet, beginning 1 week after the carcinogen challenge for prevention or 8 weeks later for treatment. The number, size, and severity of tumors in the lungs were then evaluated. In the prevention studies, the Triterpenoids CDDO-ethyl amide and CDDO-methyl ester reduced the average tumor burden (ATB) in the lungs 86% to 92%, respectively, compared with the controls, and the rexinoid LG100268 (268) reduced ATB by 50%. The combination of CDDO-ethyl amide and 268 reduced ATB by 93%. We show for the first time that these drugs also were highly effective for treatment of experimental lung cancer, and all triterpenoid and rexinoid combinations reduced ATB 85% to 87% compared with the control group. The Triterpenoids also potently inhibited proliferation of VC1 mouse lung carcinoma cells and directly interacted with key regulatory proteins in these cells. In contrast, the rexinoids had little antiproliferative activity in VC1 cells but were potent inhibitors of the toll-like receptor pathway in macrophage-like cells. Triterpenoids and rexinoids are multifunctional, well-tolerated drugs that target different signaling pathways and are thus highly effective for prevention and treatment of experimental lung cancer.
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pharmacodynamic characterization of chemopreventive Triterpenoids as exceptionally potent inducers of nrf2 regulated genes
Molecular Cancer Therapeutics, 2007Co-Authors: Melinda S Yates, Masafumi Tauchi, Fumiki Katsuoka, Kathleen C Flanders, Karen T Liby, Tadashi Honda, Gordon W Gribble, Delinda A Johnson, Jeffrey A Johnson, Neal C BurtonAbstract:Synthetic Triterpenoids have been developed, which are potent inducers of cytoprotective enzymes and inhibitors of inflammation, greatly improving on the weak activity of naturally occurring Triterpenoids. An imidazolide triterpenoid derivative, 1-[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im or TP235), has been previously shown to potently protect against hepatic tumorigenesis, acting in part by inducing cytoprotective genes through Keap1-Nrf2-antioxidant response element (ARE) signaling. In these studies, the pharmacodynamic activity of CDDO-Im is characterized in two distinct lines of ARE reporter mice and by measuring increases in Nqo1 transcript levels as a marker of cytoprotective gene induction. Oral administration of CDDO-Im induces ARE-regulated cytoprotective genes in many tissues in the mouse, including liver, lung, kidney, intestines, brain, heart, thymus, and salivary gland. CDDO-Im induces Nqo1 RNA transcripts in some organs at doses as low as 0.3 μmol/kg body weight (orally). A structure activity evaluation of 15 additional Triterpenoids ( a ) confirmed the importance of Michael acceptor groups on both the A and C rings, ( b ) showed the requirement for a nitrile group at C-2 of the A ring, and ( c ) indicated that substituents at C-17 dramatically affected pharmacodynamic action in vivo . In addition to CDDO-Im, other Triterpenoids, particularly the methyl ester CDDO-Me (TP155) and the dinitrile TP225, are extremely potent inducers of cytoprotective genes in mouse liver, lung, small intestine mucosa, and cerebral cortex. This pharmacodynamic characterization highlights the chemopreventive promise of several synthetic Triterpenoids in multiple target organs. [Mol Cancer Ther 2007;6(1):154–62]
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the synthetic Triterpenoids cddo and cddo imidazolide are potent inducers of heme oxygenase 1 and nrf2 are signaling
Cancer Research, 2005Co-Authors: Karen T Liby, Tadashi Honda, Thomas D Hock, Mark M Yore, Andrew E Place, Renee Risingsong, Charlotte R Williams, Darlene B Royce, Yukiko Honda, Gordon W GribbleAbstract:The synthetic triterpenoid 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid (CDDO) and its derivative 1-[2-cyano-3-,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im) are multifunctional molecules with potent antiproliferative, differentiating, and anti-inflammatory activities. At nanomolar concentrations, these agents rapidly increase the expression of the cytoprotective heme oxygenase-1 (HO-1) enzyme in vitro and in vivo. Transfection studies using a series of reporter constructs show that activation of the human HO-1 promoter by the Triterpenoids requires an antioxidant response element (ARE), a cyclic AMP response element, and an E Box sequence. Inactivation of one of these response elements alone partially reduces HO-1 induction, but mutations in all three sequences entirely eliminate promoter activity in response to the Triterpenoids. Treatment with CDDO-Im also elevates protein levels of Nrf2, a transcription factor previously shown to bind ARE sequences, and increases expression of a number of antioxidant and detoxification genes regulated by Nrf2. The Triterpenoids also reduce the formation of reactive oxygen species in cells challenged with tert-butyl hydroperoxide, but this cytoprotective activity is absent in Nrf2 deficient cells. These studies are the first to investigate the induction of the HO-1 and Nrf2/ARE pathways by CDDO and CDDO-Im, and our results suggest that further in vivo studies are needed to explore the chemopreventive and chemotherapeutic potential of the Triterpenoids.
Mo Wang - One of the best experts on this subject based on the ideXlab platform.
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De Novo Sequencing and Transcriptome Analysis of Wolfiporia cocos to Reveal Genes Related to Biosynthesis
2016Co-Authors: Of Triterpenoids, Mengchun Zhou, Xinmei Zhao, Bei Chen, Shaohua Shu, Haiyang Xia, Mo WangAbstract:Wolfiporia cocos Ryvarden et Gilbertson is a saprophytic fungus in the Basidiomycetes. Its dried sclerotium is widely used as a traditional crude drug in East Asia. Especially in China, the dried sclerotium is regarded as the silver of the Chinese traditional drugs, not only for its white color, but also its medicinal value. Furthermore, Triterpenoids from W. cocos are the main active compounds with antitumor and anti-inflammatory activity. Biosynthesis of the Triterpenoids has rarely been researched. In this study, the de novo sequencing of the mycelia and sclerotia of W. cocos were carried out by Illumina HiSeq 2000. A total of 3,484,996,740 bp from 38,722,186 sequence reads of mycelia, and 3,573,921,960 bp from 39,710,244 high quality sequence reads of sclerotium were obtained. These raw data were assembled into 60,354 contigs and 40,939 singletons, and 56,938 contigs and 37,220 singletons for mycelia and sclerotia, respectively. The transcriptomic data clearly showed that terpenoid biosynthesis was only via the MVA pathwayin W. cocos. The production of total Triterpenoids and pachymic acid was examined in the dry mycelia and sclerotia. The content of total Triterpenoids was 5.36 % and 1.43 % in mycelia and sclerotia, respectively, and the content of pachymic acid was 0.458 % and 0.174%. Some genes involved in the triterpenoid biosynthetic pathway were chosen to be verified by qRT-PCR. The unigenes encoding diphosphomevalonate decarboxylase (Unigene 20430), farnesyl diphosphate synthase (Unigene 14106 and 21656), hydroxymethylglutaryl-CoA reductase (NADPH) (Unigene 6395_All) and lanosterol synthase (Unigene28001_All) were upregulated in the mycelia stage
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de novo sequencing and transcriptome analysis of wolfiporia cocos to reveal genes related to biosynthesis of Triterpenoids
PLOS ONE, 2013Co-Authors: Bei Chen, Mengchun Zhou, Xinmei Zhao, Mo WangAbstract:Wolfiporia cocos Ryvarden et Gilbertson is a saprophytic fungus in the Basidiomycetes. Its dried sclerotium is widely used as a traditional crude drug in East Asia. Especially in China, the dried sclerotium is regarded as the silver of the Chinese traditional drugs, not only for its white color, but also its medicinal value. Furthermore, Triterpenoids from W. cocos are the main active compounds with antitumor and anti-inflammatory activity. Biosynthesis of the Triterpenoids has rarely been researched. In this study, the de novo sequencing of the mycelia and sclerotia of W. cocos were carried out by Illumina HiSeq 2000. A total of 3,484,996,740 bp from 38,722,186 sequence reads of mycelia, and 3,573,921,960 bp from 39,710,244 high quality sequence reads of sclerotium were obtained. These raw data were assembled into 60,354 contigs and 40,939 singletons, and 56,938 contigs and 37,220 singletons for mycelia and sclerotia, respectively. The transcriptomic data clearly showed that terpenoid biosynthesis was only via the MVA pathwayin W. cocos. The production of total Triterpenoids and pachymic acid was examined in the dry mycelia and sclerotia. The content of total Triterpenoids was 5.36% and 1.43% in mycelia and sclerotia, respectively, and the content of pachymic acid was 0.458% and 0.174%. Some genes involved in the triterpenoid biosynthetic pathway were chosen to be verified by qRT-PCR. The unigenes encoding diphosphomevalonate decarboxylase (Unigene 20430), farnesyl diphosphate synthase (Unigene 14106 and 21656), hydroxymethylglutaryl-CoA reductase (NADPH) (Unigene 6395_All) and lanosterol synthase (Unigene28001_All) were upregulated in the mycelia stage. It is likely that expression of these genes influences the biosynthesis of Triterpenoids in the mycelia stage.
Xing Hu - One of the best experts on this subject based on the ideXlab platform.
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determination of the five main terpenoids in different tissues of wolfiporia cocos
Molecules, 2018Co-Authors: Ming Fu, Boxia Deng, Xianyou Wang, Li Wang, Xing HuAbstract:Wolfiporia cocos is a fungus containing Triterpenoids and is widely used as an herbal medicine. However, it is unknown whether its main triterpenoid contents differ in different tissues. In this study, we identified dehydrotumulosic acid, polyporenic acid C, pachymic acid, dehydrotrametenolic acid, and dehydroeburicoic acid as the five main Triterpenoids in W. cocos. We also systematically profiled the contents and distribution of these main Triterpenoids in different tissues of W. cocos. High contents of all five Triterpenoids were found in the surface layer of W. cocos. Intriguingly, we noted that the highest contents of the five Triterpenoids were found in the surface layer of the sclerotium grown under pollution-controlled cultivation; the second-highest contents were found in the surface layer of the natural sclerotium. These results indicate that environmentally friendly cultivation of the sclerotium of W. cocos is a practical way to increase the productivity of W. cocos. In addition, our findings suggest that the Triterpenoids may contribute to the pharmacological activity of W. cocos, and the surface layer of sclerotium in W. cocos might be a promising raw material for applications in health care and the development of functional medical products.
