The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Yong-xian Cheng - One of the best experts on this subject based on the ideXlab platform.
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Commipholactam A, a cytotoxic sesquiterpenoidal lactam from Resina Commiphora.
Fitoterapia, 2019Co-Authors: Shao-xiang Wang, Cui Yang, Gan-peng Li, Yong-xian ChengAbstract:Abstract Diverse terpenoids including a novel sesquiterpenoidal lactam, commipholactam A (1), and a structurally related new cadinane sesquiterpenoid, Commiphorane H (2), a new eudesmane sesquiterpenoid, Commiphorane I (4), a new guaiane sesquiterpenoid, Commiphorane J (5), and two new nor-abietane diterpenoids, Commiphoranes K1 and K2 (6 and 7) along with two known terpenoids (3 and 8), were isolated from Resina Commiphora. Their structures with absolute configurations were characterized by spectroscopic methods and calculated electronic circular dichroism (ECD). Notably, commipholactam A represents the first example of cadinane sesquiterpene alkaloids isolated from Resina Commiphora. Biological assessment toward human cancer cells showed that the IC50 values of 1 against HepG2 and A549 cells were 21.73 μM and 128.50 μM, respectively.
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Commiphoratones a and b two sesquiterpene dimers from resina Commiphora
Organic Letters, 2018Co-Authors: Jing Yang, Yong-xian Cheng, Xifeng LuAbstract:Two sesquiterpene dimers, Commiphoratones A (1) and B (2), were isolated from Resina Commiphora. Their structures were elucidated by spectroscopic, computational, and crystallographic methods. Compounds 1 and 2 represent an unusual pattern of dimerization between two types of sesquiterpenes. Moreover, compound 1 has a saddle shape. The plausible biosynthetic pathway for 1 and 2 is presented. Bioassay showed that 1 and 2 significantly block lipid metabolism in a concentration-dependent manner.
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new terpenoids from resina Commiphora
Fitoterapia, 2017Co-Authors: Yong-xian Cheng, Lu Dong, Lizhi Cheng, Shumei WangAbstract:Abstract Three new eudesmane sesquiterpenoids, Commiphoranes E1–E3 (1–3), a new podocarpane diterpenoid, Commiphorane F (4), three new triterpenoids, Commiphoranes G1-G3 (5–7), and fourteen known terpenoids (8–21) were isolated from Resina Commiphora. The structures and relative configurations of new compounds were mainly assigned by spectroscopic methods. In particular, the absolute configuration of 3 was clarified by computational methods. Renoprotective effects of all these isolates were evaluated by using an ELISA assay in TGF-β1-induced rat kidney tubular epithelial cells. The present findings add new facets for chemical profiling of plant resins.
Katrin Bohninggaese - One of the best experts on this subject based on the ideXlab platform.
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consequences of frugivore diversity for seed dispersal seedling establishment and the spatial pattern of seedlings and trees
Oecologia, 2001Co-Authors: Barbel Bleher, Katrin BohninggaeseAbstract:Many plants depend on frugivorous animals for the dispersal of their seeds. However, it is only poorly known whether regional differences in frugivore diversity have consequences for seed dispersal, seedling establishment, and the spatial distribution of seedlings and trees. This comparative study of seed dispersal investigated the consequences of regional differences in frugivore diversity for two tree species of the genus Commiphora. C. harveyi was studied in South Africa where avian frugivore diversity is high, C. guillaumini was studied in Madagascar where the avian frugivore community is depauperate. At both study sites, the percentages of handled and dispersed seeds in Commiphora trees were quantified by fruit traps, and visitation rates, seed handling rates and dispersal rates were quantified for each animal species for two consecutive years. Seedlings were mapped and the spatial distribution of trees quantified. At both study sites, fruits were mainly eaten by birds. The total percentage of dispersed seeds in South Africa was significantly higher than in Madagascar (70.8% vs. 7.9%) because there was a lack of effective dispersers that swallowed seeds in Madagascar. Seed dispersal benefit, i.e. the increase in the probability of becoming established as a seedling away from parent trees due to dispersal was much higher in Madagascar (80 times higher probability) compared to South Africa (6 times higher). Corresponding with the different dispersal percentages, seedlings in South Africa were found at relatively large distances from the nearest Commiphora tree (median distance=21.0 m), whereas in Madagascar seedlings were found mostly under and close to the nearest Commiphora tree (median distance=0.9 m). Finally, Commiphora trees in the Malagasy study site were clumped, but were more randomly distributed in the South African study site. These results suggest that regional differences in frugivore diversity and behaviour strongly affect seed dispersal of trees, seedling establishment and the spatial distribution of seedlings and trees.
Chitang Ho - One of the best experts on this subject based on the ideXlab platform.
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isolation and characterization of several aromatic sesquiterpenes from Commiphora myrrha
Flavour and Fragrance Journal, 2003Co-Authors: Shuqun Sheng, Shengmin Sang, Robert T Rosen, Chitang HoAbstract:The purification and structure characterization of seven aromatic sesquiterpenes from scented Commiphora myrrha are reported. Their structures were determined on the basis of spectral data, especially of NMR evidence. Among them, compound 1 is a new furanosesquiterpene and compound 2 is identified as a new natural aroma found in Commiphora spp. All compounds except 4 were isolated, for the first time, from Commiphora myrrha. Copyright © 2003 John Wiley & Sons, Ltd.
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furanosesquiterpenoids of Commiphora myrrha
Journal of Natural Products, 2001Co-Authors: Hiroe Kikuzaki, Shuqun Sheng, Shengmin Sang, Robert T Rosen, Mohamed M Rafi, Mingfu Wang, Nobuji Nakatani, Robert S Dipaola, Chitang HoAbstract:An investigation on the gum exudates of Commiphora myrrha has led to the isolation of six sesquiterpenoids. On the basis of spectroscopic data interpretation, they were determined as two new furanosesquiterpenoids, rel-1S,2S-epoxy-4R-furanogermacr-10(15)-en-6-one (1) and rel-2R-methyl-5S-acetoxy-4R-furanogermacr-1(10)Z-en-6-one (2), and four known furanosesquiterpenoids, rel-3R-methoxy-4S-furanogermacra-1E,10(15)-dien-6-one (3), rel-2R-methoxy-4R-furanogermacr-1(10)E-en-6-one (4), furanogermacra-1(10)Z,4Z-dien-6-one, and curzerenone [6,7-dihydro-5β-isopropenyl-3,6β-dimethyl-6-vinylbenzofuran-4(5H)-one]. This is the first report of the relative stereochemistry for the known compounds 3 and 4. Compound 1 exhibited weak cytotoxic activity against a MCF-7 breast tumor cell line in a clonogenic assay, while the other five compounds were inactive in this assay.
Lu Dong - One of the best experts on this subject based on the ideXlab platform.
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new terpenoids from resina Commiphora
Fitoterapia, 2017Co-Authors: Yong-xian Cheng, Lu Dong, Lizhi Cheng, Shumei WangAbstract:Abstract Three new eudesmane sesquiterpenoids, Commiphoranes E1–E3 (1–3), a new podocarpane diterpenoid, Commiphorane F (4), three new triterpenoids, Commiphoranes G1-G3 (5–7), and fourteen known terpenoids (8–21) were isolated from Resina Commiphora. The structures and relative configurations of new compounds were mainly assigned by spectroscopic methods. In particular, the absolute configuration of 3 was clarified by computational methods. Renoprotective effects of all these isolates were evaluated by using an ELISA assay in TGF-β1-induced rat kidney tubular epithelial cells. The present findings add new facets for chemical profiling of plant resins.
Alvaro Viljoen - One of the best experts on this subject based on the ideXlab platform.
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the in vitro biological activity of selected south african Commiphora species
Journal of Ethnopharmacology, 2008Co-Authors: M P Paraskeva, S F Van Vuuren, Hajierah Davids, Alvaro ViljoenAbstract:Abstract Ten South African Commiphora (Burseraceae) species were investigated to validate their use in traditional healing rites. The leaf and stem extracts of each species were analysed for the anti-oxidant (ABTS and DPPH assays), antimicrobial (MIC and death kinetic assays), anti-inflammatory (5-LOX assay), anticancer (SRB assay) properties, as well as the cytotoxic effects (tetrazolium-based assay). The best anti-oxidant activity (ABTS assay) was observed for the stem extracts of Commiphora tenuipetiolata IC50 = 5.10 μg/ml), Commiphora neglecta (IC50 = 7.28 μg/ml) and Commiphora mollis (IC50 = 8.82 μg/ml). Extracts generally exhibited poor anti-oxidant activity in the DPPH assay, with the exception of Commiphora schimperi (stem), Commiphora neglecta (stem), Commiphora tenuipetiolata (stem and leaf), and Commiphora edulis (stem), with IC50 values ranging between 7.31 and 10.81 μg/ml. The stem extracts exhibited moderate to good 5-LOX inhibitory activity with Commiphora pyracanthoides (stem) displaying the greatest inhibitory effect (IC50 = 27.86 ± 4.45 μg/ml). For the antimicrobial (MIC) assay, a greater selectivity was exhibited by the extracts against the Gram-positive bacteria (0.01–8.00 mg/ml) and the yeasts (0.25–8.00 mg/ml) than against the Gram-negative bacteria (1.00–8.00 mg/ml). Using death kinetic studies (time–kill studies), the rate at which Commiphora marlothii (stem) kills Staphylococcus aureus over a 24 h period was determined. Mostly, a concentration-dependent antibacterial activity was observed beginning after ca. 30 min. All concentrations exhibited antibacterial activity, with complete bactericidal effect achieved by the 24th hour. The most active Commiphora species against the HT-29 cells (SRB anticancer assay) were Commiphora glandulosa (leaf and stem) and Commiphora marlothii (leaf). The MCF-7 cells (SRB anticancer assay) exhibited the highest sensitivity to indigenous Commiphora species, with Commiphora edulis (leaf and stem), Commiphora glandulosa (leaf and stem), Commiphora marlothii (leaf), Commiphora pyracanthoides (leaf and stem), Commiphora schimperi (stem), and Commiphora viminea (stem) all possessing a percentage inhibition greater than 80% at 100 μg/ml. Commiphora glandulosa (leaf and stem) and Commiphora pyracanthoides (leaf and stem) were the two most active species against the SF-268 cells (SRB anticancer assay), with IC50 values ranging between 68.55 ± 2.01 and 71.45 ± 1.24 μg/ml. The majority of the Commiphora extracts were largely non-cytotoxic against Graham human kidney epithelial cells when investigated in the MTT assay.