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Peilin Wu - One of the best experts on this subject based on the ideXlab platform.
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alkaloidal and other constituents from the root bark of clausena Excavata
Phytochemistry, 1999Co-Authors: Tian Shung Wu, Peilin Wu, Shiow Chyn Huang, Changsheng KuohAbstract:Ten new carbazole alkaloids, clausine-M, -N, -O, -P, -Q, -R, -S, -U, -V and clausenatine-A, together with 39 known compounds were isolated and identified from the acetone extract of the root bark of Clausena Excavata. Their structures have been elucidated by spectroscopic analyses. This is the first report of a decarboxylated carbazole alkaloid from a natural source. The presence of a C23-skeleton carbazole alkaloid in a plant of Clausena genus is also reported for the first time.
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lactonic carbazole alkaloids from the root bark of clausena Excavata
Chemical & Pharmaceutical Bulletin, 1998Co-Authors: Tian Shung Wu, Shiowchyn C Huang, Peilin WuAbstract:Examination of the extract from the root bark of Clausena Excavata, yielded four new lactonic carbaczole alkaloids, clausevatine-D (1), -E (2), -F (3), -G (4), as well as the known clausamine-A (5). Their structures were elucidated by spectroscopic analyses.
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two coumarins from the root bark of clausena Excavata
Phytochemistry, 1997Co-Authors: Shiowchyn C Huang, Peilin Wu, Tian Shung WuAbstract:Two new pyrano-coumarins, claucavatin-A and -B, together with eight known coumarins and two known flavonoids were isolated and identified from the acetone extract of the root bark of Clausena Excavata. Their structures were elucidated by the spectroscopic analyses.
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carbazole alkaloids from stem bark of clausena Excavata
Phytochemistry, 1996Co-Authors: Tian Shung Wu, Shiow Chyn Huang, Peilin WuAbstract:Abstract Four new carbazole alkaloids, clausines A, C, G and J were identified as 3-formyl-2-hydroxy-8-methoxycarbazole 3-carbomethoxy-7-methoxycarbazole, 3-carbomethoxy-1-hydroxy-6-methoxycarbazole and 3-formyl-1, 7-dihydroxy-6-methoxycarbazole, respectively, from a methanol extract of the stem bark of Clausena Excavata . Structures were established by spectroscopic analyses.
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carbazole pyranocoumarin dimer and binary carbazole alkaloid from clausena Excavata
Tetrahedron Letters, 1996Co-Authors: Tian Shung Wu, Shiow Chyn Huang, Peilin WuAbstract:Abstract Examination of the extract from the stem bark and root bark of Clausena Excavata , a binary carbazole alkaloid, clausenamine-A ( 1 ), and a carbazole-pyranocoumarin dimer, carbazomarin-A ( 2 ), were isolated, respectively. Their structures were elucidated by spectroscopic analyses.
Tian Shung Wu - One of the best experts on this subject based on the ideXlab platform.
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alkaloidal and other constituents from the root bark of clausena Excavata
Phytochemistry, 1999Co-Authors: Tian Shung Wu, Peilin Wu, Shiow Chyn Huang, Changsheng KuohAbstract:Ten new carbazole alkaloids, clausine-M, -N, -O, -P, -Q, -R, -S, -U, -V and clausenatine-A, together with 39 known compounds were isolated and identified from the acetone extract of the root bark of Clausena Excavata. Their structures have been elucidated by spectroscopic analyses. This is the first report of a decarboxylated carbazole alkaloid from a natural source. The presence of a C23-skeleton carbazole alkaloid in a plant of Clausena genus is also reported for the first time.
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lactonic carbazole alkaloids from the root bark of clausena Excavata
Chemical & Pharmaceutical Bulletin, 1998Co-Authors: Tian Shung Wu, Shiowchyn C Huang, Peilin WuAbstract:Examination of the extract from the root bark of Clausena Excavata, yielded four new lactonic carbaczole alkaloids, clausevatine-D (1), -E (2), -F (3), -G (4), as well as the known clausamine-A (5). Their structures were elucidated by spectroscopic analyses.
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two coumarins from the root bark of clausena Excavata
Phytochemistry, 1997Co-Authors: Shiowchyn C Huang, Peilin Wu, Tian Shung WuAbstract:Two new pyrano-coumarins, claucavatin-A and -B, together with eight known coumarins and two known flavonoids were isolated and identified from the acetone extract of the root bark of Clausena Excavata. Their structures were elucidated by the spectroscopic analyses.
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carbazole alkaloids from stem bark of clausena Excavata
Phytochemistry, 1996Co-Authors: Tian Shung Wu, Shiow Chyn Huang, Peilin WuAbstract:Abstract Four new carbazole alkaloids, clausines A, C, G and J were identified as 3-formyl-2-hydroxy-8-methoxycarbazole 3-carbomethoxy-7-methoxycarbazole, 3-carbomethoxy-1-hydroxy-6-methoxycarbazole and 3-formyl-1, 7-dihydroxy-6-methoxycarbazole, respectively, from a methanol extract of the stem bark of Clausena Excavata . Structures were established by spectroscopic analyses.
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carbazole pyranocoumarin dimer and binary carbazole alkaloid from clausena Excavata
Tetrahedron Letters, 1996Co-Authors: Tian Shung Wu, Shiow Chyn Huang, Peilin WuAbstract:Abstract Examination of the extract from the stem bark and root bark of Clausena Excavata , a binary carbazole alkaloid, clausenamine-A ( 1 ), and a carbazole-pyranocoumarin dimer, carbazomarin-A ( 2 ), were isolated, respectively. Their structures were elucidated by spectroscopic analyses.
Alastair G. B. Simpson - One of the best experts on this subject based on the ideXlab platform.
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comprehensive ultrastructure of kipferlia bialata provides evidence for character evolution within the fornicata Excavata
Protist, 2013Co-Authors: Naoji Yubuki, Alastair G. B. Simpson, Brian S LeanderAbstract:Carpediemonas-like organisms (CLOs) are important for understanding the evolutionary history of anaerobic excavates (e.g. diplomonads and parabasalids), especially their cytoskeletal traits and the functions of their modified mitochondria (e.g., hydrogenosomes and mitosomes). Kipferlia bialata is probably the most commonly encountered CLO and has an intriguing molecular phylogenetic position within the Fornicata; however, this species has yet to be described at the ultrastructural level. This study provides a comprehensive account of the ultrastructure of this excavate using light microscopy, SEM, and serial TEM sectioning. The pattern of flagellar transformation observed with SEM confirms that the posterior basal body is the ‘eldest’, enabling us to emend the numbering system and associated terminology of the flagellar apparatus in excavates. This revised terminology is fundamental for comparing the cytoskeletons of the Excavata supergroup with other eukaryotes. Moreover, K. bialata had several unusal features, such as a hood, a distinct gutter within the ventral groove, and hairs along a single flagellar vane. The ultrastractural data reported here significantly improve our understanding of fornicate morphology, and when placed within a molecular phylogenetic context, these data shed light onto patterns of character evolution within the Excavata.
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phylogenomic analyses support the monophyly of Excavata and resolve relationships among eukaryotic supergroups
Proceedings of the National Academy of Sciences of the United States of America, 2009Co-Authors: Vladimir Hampl, Joel B. Dacks, Franz B Lang, Alastair G. B. Simpson, Jessica W Leigh, Andrew J. RogerAbstract:Nearly all of eukaryotic diversity has been classified into 6 suprakingdom-level groups (supergroups) based on molecular and morphological/cell-biological evidence; these are Opisthokonta, Amoebozoa, Archaeplastida, Rhizaria, Chromalveolata, and Excavata. However, molecular phylogeny has not provided clear evidence that either Chromalveolata or Excavata is monophyletic, nor has it resolved the relationships among the supergroups. To establish the affinities of Excavata, which contains parasites of global importance and organisms regarded previously as primitive eukaryotes, we conducted a phylogenomic analysis of a dataset of 143 proteins and 48 taxa, including 19 excavates. Previous phylogenomic studies have not included all major subgroups of Excavata, and thus have not definitively addressed their interrelationships. The enigmatic flagellate Andalucia is sister to typical jakobids. Jakobids (including Andalucia), Euglenozoa and Heterolobosea form a major clade that we name Discoba. Analyses of the complete dataset group Discoba with the mitochondrion-lacking excavates or “metamonads” (diplomonads, parabasalids, and Preaxostyla), but not with the final excavate group, Malawimonas. This separation likely results from a long-branch attraction artifact. Gradual removal of rapidly-evolving taxa from the dataset leads to moderate bootstrap support (69%) for the monophyly of all Excavata, and 90% support once all metamonads are removed. Most importantly, Excavata robustly emerges between unikonts (Amoebozoa + Opisthokonta) and “megagrouping” of Archaeplastida, Rhizaria, and chromalveolates. Our analyses indicate that Excavata forms a monophyletic suprakingdom-level group that is one of the 3 primary divisions within eukaryotes, along with unikonts and a megagroup of Archaeplastida, Rhizaria, and the chromalveolate lineages.
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cytoskeletal organization phylogenetic affinities and systematics in the contentious taxon Excavata eukaryota
International Journal of Systematic and Evolutionary Microbiology, 2003Co-Authors: Alastair G. B. SimpsonAbstract:An overview of the controversial proposal for the major eukaryote taxon ‘Excavata’ is presented. Excavata is predicted to include at least ten distinct groups: jakobids, Malawimonas, Trimastix, Carpediemonas, retortamonads, diplomonads, Heterolobosea, oxymonads, parabasalids and Euglenozoa. These ‘excavates' have broadly similar flagellar apparatus organizations, for which a ‘universal’ terminology is provided. Most, but not all, of these organisms share a distinctive suspension-feeding groove, as well as some or all of a set of seven other proposed cytoskeletal apomorphies. Cladistic analyses of morphological data do not resolve high-level relationships within Excavata. Excavate-rich molecular phylogenies recover some robust clades, but do not support or strongly refute the monophyly of Excavata. A partial classification for excavates is presented, with phylogenetic diagnoses for Excavata and for two novel taxon names, Fornicata (Carpediemonas, retortamonads, diplomonads) and Preaxostyla (Trimastix, oxymonads).
Vladimir Hampl - One of the best experts on this subject based on the ideXlab platform.
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phylogenomic analyses support the monophyly of Excavata and resolve relationships among eukaryotic supergroups
Proceedings of the National Academy of Sciences of the United States of America, 2009Co-Authors: Vladimir Hampl, Joel B. Dacks, Franz B Lang, Alastair G. B. Simpson, Jessica W Leigh, Andrew J. RogerAbstract:Nearly all of eukaryotic diversity has been classified into 6 suprakingdom-level groups (supergroups) based on molecular and morphological/cell-biological evidence; these are Opisthokonta, Amoebozoa, Archaeplastida, Rhizaria, Chromalveolata, and Excavata. However, molecular phylogeny has not provided clear evidence that either Chromalveolata or Excavata is monophyletic, nor has it resolved the relationships among the supergroups. To establish the affinities of Excavata, which contains parasites of global importance and organisms regarded previously as primitive eukaryotes, we conducted a phylogenomic analysis of a dataset of 143 proteins and 48 taxa, including 19 excavates. Previous phylogenomic studies have not included all major subgroups of Excavata, and thus have not definitively addressed their interrelationships. The enigmatic flagellate Andalucia is sister to typical jakobids. Jakobids (including Andalucia), Euglenozoa and Heterolobosea form a major clade that we name Discoba. Analyses of the complete dataset group Discoba with the mitochondrion-lacking excavates or “metamonads” (diplomonads, parabasalids, and Preaxostyla), but not with the final excavate group, Malawimonas. This separation likely results from a long-branch attraction artifact. Gradual removal of rapidly-evolving taxa from the dataset leads to moderate bootstrap support (69%) for the monophyly of all Excavata, and 90% support once all metamonads are removed. Most importantly, Excavata robustly emerges between unikonts (Amoebozoa + Opisthokonta) and “megagrouping” of Archaeplastida, Rhizaria, and chromalveolates. Our analyses indicate that Excavata forms a monophyletic suprakingdom-level group that is one of the 3 primary divisions within eukaryotes, along with unikonts and a megagroup of Archaeplastida, Rhizaria, and the chromalveolate lineages.
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inference of the phylogenetic position of oxymonads based on nine genes support for metamonada and Excavata
Molecular Biology and Evolution, 2005Co-Authors: Vladimir Hampl, David S Horner, Patricia Dyal, Jaroslav Kulda, Jaroslav Flegr, Peter G Foster, Martin T EmbleyAbstract:: Circumscribing major eukaryote groups and resolving higher order relationships between them are among the most challenging tasks facing molecular evolutionists. Recently, evidence suggesting a new supergroup (the Excavata) comprising a wide array of flagellates has been collected. This group consists of diplomonads, retortamonads, Carpediemonas, heteroloboseans, Trimastix, jakobids, and Malawimonas, all of which possess a particular type of ventral feeding groove that is proposed to be homologous. Euglenozoans, parabasalids, and oxymonads have also been associated with Excavata as their relationships to one or more core excavate taxa were demonstrated. However, the main barrier to the general acceptance of Excavata is that its existence is founded primarily on cytoskeletal similarities, without consistent support from molecular phylogenetics. In gene trees, Excavata are typically not recovered together. In this paper, we present an analysis of the phylogenetic position of oxymonads (genus Monocercomonoides) based on concatenation of eight protein sequences (alpha-tubulin, beta-tubulin, gamma-tubulin, EF-1alpha, EF-2, cytosolic (cyt) HSP70, HSP90, and ubiquitin) and 18S rRNA. We demonstrate that the genes are in conflict regarding the position of oxymonads. Concatenation of alpha- and beta-tubulin placed oxymonads in the plant-chromist part of the tree, while the concatenation of other genes recovered a well-supported group of Metamonada (oxymonads, diplomonads, and parabasalids) that branched weakly with euglenozoans--connecting all four excavates included in the analyses and thus providing conditional support for the existence of Excavata.
Noorlidah Abdullah - One of the best experts on this subject based on the ideXlab platform.
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methanolic extract of clausena Excavata promotes wound healing via antiinflammatory and anti apoptotic activities
Asian pacific Journal of Tropical Biomedicine, 2020Co-Authors: Shaymaa Fadhel Abbas Albaayit, Abdullah Rasedee, Noorlidah Abdullah, Yusuf AbbaAbstract:Objective: To investigate the anti-inflammatory properties of methanolic extract of Clausena Excavata in lipopolysaccharide (LPS)-activated macrophages (J774A.1) and the effect on skin wound in a rat model through determining cytokine levels and gene expressions. Methods: The effects of methanolic extract of Clausena Excavata on in vitro viability and TNF-α, IL-6, IL-10, and nitric oxide release by LPS-activated J774A.1 cells were determined. In addition, relative expressions of BAX, BCL-2 and COX-2 genes were examined in healed wounds of rats. Results: The methanolic extract of Clausena Excavata was not toxic to J774A.1 cells at the highest dose of 400 μg/mL. It decreased levels of TNF-α and IL-6, while increasing IL-10 level in LPS- activated J774A.1 cells and in the healed wounds of rats. The methanolic extract of Clausena Excavata also inhibited nitric oxide production in LPS-activated J774A.1 cells. The BAX and COX-2 genes were downregulated while the BCL-2 gene was upregulated in the healed wound of rats. Conclusions: The methanolic extract of Clausena Excavata promotes wound healing via its anti-inflammatory and anti-apoptotic activities.
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Prophylactic effects of Clausena Excavata Burum. f. leaf extract in ethanol-induced gastric ulcers
Drug Design Development and Therapy, 2016Co-Authors: Shaymaa Fadhel Abbas Albaayit, Yusuf Abba, Rasedee Abdullah, Noorlidah AbdullahAbstract:Clausena Excavata is a natural herb with both antioxidant and anti-inflammatory properties. It has been used for decades in folkloric practice for the amelioration of various ailments. In this study, the gastroprotective activity of methanolic extract of C. Excavata leaves (MECE) was determined in the Sprague Dawley rat ethanol-induced gastric ulcer model. Rats were pretreated with a single dose of vehicle (5% Tween 20), 20 mg/mL omeprazole, 400 and 200 mg/mL of MECE dissolved in 5% Tween 20. Ulcer was induced with 5 mL/kg of ethanol and stomach tissue was obtained after 1 hour. Histological examination was done on hematoxylin and eosin, periodic acid-Schiff, and immunochemically stained gastric mucosal tissues. Prostaglandin E2, superoxide dismutase, catalase, glutathione peroxidase, and lipid peroxidation levels of the gastric tissue homogenates were also determined. Significantly (P
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Effect of Clausena Excavata Burm. f. (Rutaceae) leaf extract on wound healing and antioxidant activity in rats.
Drug Design Development and Therapy, 2015Co-Authors: Shaymaa Fadhel Abbas Albaayit, Abdullah Rasedee, Yusuf Abba, Noorlidah AbdullahAbstract:Clausena Excavata is a well-known plant used in folkloric medicine for the treatment of different ailments. This study aimed to determine the in vitro cytoxicity of its leaf solvent extracts as well as the in vivo wound healing and antioxidant activities of the methanolic extracts of C. Excavata (MECE). HaCaT (keratocyte) and Vero cell lines were used for evaluation of the in vitro cytotoxic effects, while the in vivo wound healing and antioxidant activities were determined in skin wounds inflicted on rats. Twenty adult male Sprague-Dawley rats were divided into five groups of four animals each. Approximately 3.14 cm2 excisional wound was inflicted on the nape of each rat following anesthesia. The treatment groups received topical application of MECE at 50 mg/mL (MECE-LD [low dose]), 100 mg/mL (MECE-MD [medium dose]), and 200 mg/mL (MECE-HD [high dose]), while the negative control group was treated with gum acacia in normal saline and the positive control group with intrasite gel. Wound contraction was evaluated on days 5, 10, and 15 after wound infliction, and tissue from wound area was collected at day 15 post-wound infliction for antioxidant enzyme evaluation and histopathological analyses. Generally, Vero cells were more resistant to the cytotoxic effects of the solvent extracts as compared with HaCaT cells. Chloroform (CH) and ethyl acetate (EA) extracts of C. Excavata were toxic to HaCaT cells at 200 and 400 µg/mL, but the same concentrations showed higher (P
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evaluation of antioxidant activity and acute toxicity of clausena Excavata leaves extract
Evidence-based Complementary and Alternative Medicine, 2014Co-Authors: Shaymaa Fadhel Abbas Albaayit, Yusuf Abba, Rasedee Abdullah, Noorlidah AbdullahAbstract:Clausena Excavata (Lour.), locally known as “Kemantu hitam,” is a common plant in Malaysian folklore medicine. This study evaluated the antioxidant properties of the solvent extracts of C. Excavata leaves and determined the acute toxicity of methanolic extract C. Excavata (MECE) leaves in Sprague-Dawley rats. Harvested leaves were dried and subjected to solvent extraction using petroleum ether, chloroform, ethyl acetate and methanol in succession. The antioxidant activity of each extract was determined using the ferric-reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picryl dihydrazyl (DPPH) radical scavenging activity. The total phenolic content (TPC) and total flavonoids content (TFC) were estimated by Folin-Ciocalteu and ethanolic aluminium chloride method, respectively. The chloroform extract was found to be highest in flavonoid content, while the methanolic extract showed the highest TPC and antioxidant activity. There was no mortality in rats treated with MECE leaves even at a high dose of 5000 mg/kg body weight. However, the MECE leaves produced mild to moderate pathological changes in the liver and kidneys, shown by mild degenerative changes and leucocyte infiltration. The extract did not affect the haematological parameters or relative weights of the liver or kidneys. Overall, the MECE leaves have potent antioxidant activity and are presumed safe to be used orally as health-promoting product at low to moderate doses.
