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Olaranont Y, Mas-Claret E, Cheek M, Prescott TA, Onana JM, Langat MK. Cytotoxic ent-abietane diterpenoids, banyangmbolides A-E, from the leaves of Suregada occidentalis. Heliyon 2024; 10:e25917. [PMID: 38371959 PMCID: PMC10873725 DOI: 10.1016/j.heliyon.2024.e25917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 02/02/2024] [Accepted: 02/05/2024] [Indexed: 02/20/2024] Open
Abstract
The chemical investigation of a leaf extract from a herbarium specimen of Suregada occidentalis collected in Banyang Mbo Wildlife Sanctuary, Southwest Region, Cameroon, yielded five undescribed ent-abietane diterpenoids, banyangmbolides A-E, (1-5), and four known diterpenoids, gelomulides A (6), B (7), D (8) and O (9). The structures of the isolated compounds were determined using NMR, IR, ECD and HRESIMS. Compounds 5, 7 and 8, showed 48-55% inhibition at 200 μM against FM-55-M1 human melanoma cells.
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Affiliation(s)
- Yanisa Olaranont
- Royal Botanic Gardens Kew, Richmond, TW9 3AE, Surrey, UK
- Department of Plant Science, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand
| | | | - Martin Cheek
- Royal Botanic Gardens Kew, Richmond, TW9 3AE, Surrey, UK
| | | | - Jean Michel Onana
- Department of Plant Biology, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon
- IRAD-National Herbarium of Cameroon, Yaoundé, PO Box 1601, Cameroon
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2
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Durrant A, Peron JMR, Langat MK, Robertson C, Le Gresley A. Modified PSYCHE NMR - The possibility for the direct semi-quantitation of components in mixtures. Talanta 2024; 268:125332. [PMID: 37890372 DOI: 10.1016/j.talanta.2023.125332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 10/18/2023] [Accepted: 10/21/2023] [Indexed: 10/29/2023]
Abstract
A series of commonly occurring biologically relevant compounds were analysed using internally referenced PSYCHE NMR and the accuracy/precision compared with that achieved using conventional qNMR. The effect of chemical shift, coupling constants, swept frequency pulse angle, excitation sculpting and the impact of signal overlap in mixtures was evaluated in terms of statistically significant variation between the two techniques. It is shown that suitably optimised PSYCHE NMR represents a potentially reliable method for the semi-quantitation of mixtures of compounds, whose spectroscopic signals overlap in conventional qNMR analysis and hence cannot be accurately quantified with that technique. This is of particular relevance for complex mixtures of natural products. Of particular note is the effect of the excitation sculpting block introduced to supress baseline artefacts.
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Affiliation(s)
- Arija Durrant
- School of Life Sciences Pharmacy and Chemistry, HSSCE Faculty, Kingston University, KT1 2EE, UK
| | - Jean-Marie R Peron
- School of Life Sciences Pharmacy and Chemistry, HSSCE Faculty, Kingston University, KT1 2EE, UK
| | | | - Cameron Robertson
- School of Life Sciences Pharmacy and Chemistry, HSSCE Faculty, Kingston University, KT1 2EE, UK
| | - Adam Le Gresley
- School of Life Sciences Pharmacy and Chemistry, HSSCE Faculty, Kingston University, KT1 2EE, UK.
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3
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Tcheuko AS, Hodjie BSF, Tadjong Tcho A, Mohammed FN, Ehawa Essoung FR, Isyaka MS, Mas-Claret E, Langat MK, Wansi JD, Kamdem AFW. A new 30-norfriedelane triterpnoid from Caloncoba lophocarpa (Oliv.) Gilg. (Achariaceae). Nat Prod Res 2023:1-8. [PMID: 37799106 DOI: 10.1080/14786419.2023.2263903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Accepted: 09/18/2023] [Indexed: 10/07/2023]
Abstract
The chemical investigation of the methanol extract of the roots of Caloncoba lophocarpa (Oliv.) Gilg. exhibited a new 30-norfriedelane triterpenoid, laphocarpanol (1), together with seven known compounds, caloncobalactone (2), friedelin (3), friedelanol (4), asperphernamate (5), stigmasterol (6), sitosterol (7) and sitosterol-3-O-β-D-glucopyranoside (8). The structures of the compounds were elucidated by extensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-MS) and by comparison with previously reported data. All the compounds were tested for their antifungal and antibacterial activities. Compound 1 displayed weak antibacterial effect with MIC value of 62.5 μg/mL against Shigella flexineri. All the isolates were found to be inactive against the tested fungal strains.
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Affiliation(s)
- Antoine Salvial Tcheuko
- Chemistry Laboratory, Department of Chemistry, Faculty of Science, University of Douala, Douala, Cameroon
| | | | - Alain Tadjong Tcho
- Department of Chemistry, University of Buea, Faculty of Sciences, Buea, Cameroon
| | - Foundikou Nsangou Mohammed
- Chemistry Laboratory, Department of Chemistry, Faculty of Science, University of Douala, Douala, Cameroon
| | | | - Mohammed S Isyaka
- Department of Chemical Sciences, Faculty of Science, Pen Resource University, Gombe, Nigeria
- Department of Chemical Sciences, Faculty of Science, Federal University of Kashere, Gombe, Nigeria
| | | | - Moses K Langat
- Department of Chemical Sciences, Faculty of Science, Pen Resource University, Gombe, Nigeria
- Royal Botanic Gardens Kew, Richmond, UK
| | - Jean Duplex Wansi
- Chemistry Laboratory, Department of Chemistry, Faculty of Science, University of Douala, Douala, Cameroon
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4
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Terefe EM, Okalebo FA, Derese S, Muriuki J, Mas-Claret E, Langat MK. Anti-HIV crotocascarin ω from Kenyan Croton dichogamus. Nat Prod Res 2023; 37:2809-2816. [PMID: 36278900 DOI: 10.1080/14786419.2022.2134998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 10/05/2022] [Accepted: 10/06/2022] [Indexed: 10/31/2022]
Abstract
An anti-HIV methanol-soluble fraction of a 1:1 CH2Cl2:CH3OH extract of twigs of a Kenyan Croton dichogamus yielded seven compounds, the new crotocascarin ω (1), the known β-oplopanone (2), dihydroconiferyl acetate (3), 3'(4''-hydroxyphenyl)-propyl benzoate (4), lupeol, sitosterol and stigmasterol. Crotocascarin ω (90%) inhibited HIV-1 replication with an IC50 value of 5.3 nM, and the compound was cytotoxic towards MT-4 cells presenting an IC50 value of 84 µM. In silico modelling showed that the anti-HIV activity for compound 1 could be through the HIV-1 protease inhibition.
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Affiliation(s)
- Ermias Mergia Terefe
- Department of Pharmacology and Pharmacognosy, School of Pharmacy and Health Sciences, United States International University-Africa, Nairobi, Kenya
- Department of Pharmacology and Pharmacognosy, College of Health Sciences, University of Nairobi, Nairobi, Kenya
| | - Faith A Okalebo
- Department of Pharmacology and Pharmacognosy, College of Health Sciences, University of Nairobi, Nairobi, Kenya
| | - Solomon Derese
- Department of Chemistry, University of Nairobi, Nairobi, Kenya
| | - Joseph Muriuki
- Centre for Virus Research, Kenya Medical Research Institute, Nairobi, Kenya
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Kemboi D, Langat MK, Siwe-Noundou X, Tshiwawa T, Krause RWM, Davison C, Smit CJ, de la Mare JA, Tembu VJ. 13-amino derivatives of dehydrocostus lactone display greatly enhanced selective toxicity against breast cancer cells and improved binding energies to protein kinases in silico. PLoS One 2022; 17:e0271389. [PMID: 35998145 PMCID: PMC9397875 DOI: 10.1371/journal.pone.0271389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 06/30/2022] [Indexed: 11/30/2022] Open
Abstract
The biological activities of dehydrocostus lactone and its analogues are suggested to be mediated by the lactone ring and α,β-methylene-γ-lactone. However, few studies exist on the structure-activity relationship of 13-amino derivatives of dehydrocostus latone. In this study new 13-amino derivatives of dehydrocostus lactone DHLC (1–4) were synthesized through Michael addition reactions, and were screened against three different breast cancer cell lines, namely hormone receptor positive breast cancer (MCF-7), triple-negative breast cancer (HCC70), and non-tumorigenic mammary epithelial (MCF-12A) cell lines. Dehydrocostus lactone (DHLC) exhibited IC50 values of 1.11 (selectivity index (SI) = 0.06), 24.70 (SI = 0.01) and 0.07 μM against HCC70, MCF-7 and MCF-12A cells, respectively. All the amino derivatives, except DHLC-3 displayed low micromolar IC50 values (ranging from 0.07–4.24 μM) against both breast cancer cell lines, with reduced toxicity towards MCF-12A non-tumorigenic mammary epithelial cells (SI values ranging from 6.00–126.86). DHLC-1 and DHLC-2 demonstrated the greatest selectivity for the MCF-7 cells (with SI of 121 and 126.86 respectively) over the MCF-12A cells. This reveals that, overall, the derivatives display greatly improved selectivity for breast cancer over non-tumorigenic mammary epithelial cells, with between 100-fold and 12 000-fold higher SI values. The improved docking scores were recorded for all the 13-amino dehydrocostus lactone derivatives for the enzymes analyzed. Compounds DHLC-4, and DHLC-3 recorded higher docking scores of -7.33 and -5.97 Kca/mol respectively, compared to the parent structure, dehydrocostus lactone (-5.34 Kca/mol) for protein kinase (PKC) theta (1XJD) and -6.22 and -5.88 Kca/mol, respectively for protein kinase iota (1RZR). The compounds further showed promising predicted adsorption, distribution, metabolisms and excretion (ADME) properties. Predicting the ADME properties of these derivatives is of importance in evaluating their drug-likeness, which could in turn be developed into potential drug candidates.
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Affiliation(s)
- Douglas Kemboi
- Department of Chemistry, Tshwane University of Technology, Pretoria, South Africa
- Department of Chemistry, Rhodes University, Makhanda (Grahamstown), South Africa
- * E-mail: (DK); (JT)
| | - Moses K. Langat
- Royal Botanic Gardens Kew, Kew Green, Richmond, Surrey, United Kingdom
| | - Xavier Siwe-Noundou
- Pharmaceutical Sciences Department, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | | | - Rui W. M. Krause
- Department of Chemistry, Rhodes University, Makhanda (Grahamstown), South Africa
| | - Candace Davison
- Department of Biochemistry and Microbiology, Rhodes University, Makhanda (Grahamstown), South Africa
| | - Christie Jane Smit
- Department of Biochemistry and Microbiology, Rhodes University, Makhanda (Grahamstown), South Africa
| | - Jo-Anne de la Mare
- Department of Biochemistry and Microbiology, Rhodes University, Makhanda (Grahamstown), South Africa
| | - Vuyelwa Jacqueline Tembu
- Department of Chemistry, Tshwane University of Technology, Pretoria, South Africa
- * E-mail: (DK); (JT)
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Langat MK, Kami T, Cheek M. Chemistry, taxonomy and ecology of the potentially chimpanzee-dispersed Vepris teva sp.nov. (Rutaceae) endangered in coastal thicket in the Congo Republic. PeerJ 2022; 10:e13926. [PMID: 36032959 PMCID: PMC9415428 DOI: 10.7717/peerj.13926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 07/30/2022] [Indexed: 01/19/2023] Open
Abstract
Continuing a survey of the chemistry of species of the largely continental African genus Vepris, we investigate a species previously referred to as Vepris sp. 1 of Congo. From the leaves of Vepris sp. 1 we report six compounds. The compounds were three furoquinoline alkaloids, kokusaginine (1), maculine (2), and flindersiamine (3), two acridone alkaloids, arborinine (4) and 1-hydroxy-3-methoxy-10-methylacridone (5), and the triterpenoid, ß-amyrin (6). Compounds 1-4 are commonly isolated from other Vepris species, compound 5 has been reported before once, from Malagasy Vepris pilosa, while this is the first report of ß-amyrin from Vepris. This combination of compounds has never before been reported from any species of Vepris. We test the hypothesis that Vepris sp. 1 is new to science and formally describe it as Vepris teva, unique in the genus in that the trifoliolate leaves are subsessile, with the median petiolule far exceeding the petiole in length. Similar fleshy-leathery four-locular syncarpous fruits are otherwise only known in the genus in Vepris glaberrima (formerly the monotypic genus Oriciopsis Engl.), a potential sister species, but requiring further investigation to confirm this phylogenetic position. We briefly characterise the unusual and poorly documented Atlantic coast equatorial ecosystem, where Vepris teva is restricted to evergreen thicket on white sand, unusual in a genus usually confined to evergreen forest. This endemic-rich ecosystem with a unique amphibian as well as plants, extends along the coastline from the mouth of the Congo River to southern Rio Muni, a distance of about 1,000 km, traversing five countries. We map and illustrate Vepris teva and assess its extinction risk as Endangered (EN B1ab(iii)+B2ab(iii)) using the IUCN, 2012 standard. Only three locations are known, and threats include port and oil refinery construction and associated activities, with only one protected location, the Jane Goodall Institute's Tchimpounga Reserve. Initial evidence indicates that the seeds of Vepris teva are dispersed by chimpanzees, previously unreported in the genus.
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Affiliation(s)
- Moses K. Langat
- Science, Royal Botanic Gardens, Kew, Richmond, United Kingdom
| | - Teva Kami
- Herbier National, Institut de Recherche National en Sciences Exactes et Naturelles (IRSEN), Brazzaville, Republic of Congo
| | - Martin Cheek
- Science, Royal Botanic Gardens, Kew, Richmond, United Kingdom
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7
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Terefe EM, Okalebo FA, Derese S, Muriuki J, Rotich W, Mas-Claret E, Sadgrove N, Padilla-González GF, Prescott TAK, Siddique H, Langat MK. Constituents of Croton megalocarpus with Potential Anti-HIV Activity. J Nat Prod 2022; 85:1861-1866. [PMID: 35709365 DOI: 10.1021/acs.jnatprod.1c01013] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Reported herein is an anti-HIV monochlorinated compound, 1β-acetoxy-3β-chloro-5α,6α-dihydroxycrotocascarin L (1), of the rare crotofolane diterpenoid class. Compound 1, a suspected artifact of extraction, along with the previously undescribed 11β-acetoxycrotocascarin L (2) and a known compound, crotocascarin K (3), were isolated from the bark of Croton megalocarpus, a Kenyan oil-producing seed crop. Compounds 1 and 3 inhibited HIV-1 replication with IC50 values of 28 and 5.5 nM, respectively. Furthermore, both compounds lacked cytotoxicity toward MT-4 cells and FM-55-M1 cells at concentrations of up to 50 μM. Compounds 1 and 3 were both found to inhibit HIV-1 protease.
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Affiliation(s)
- Ermias Mergia Terefe
- Department of Pharmacology and Pharmacognosy, School of Pharmacy and Health Sciences, United States International University-Africa, 14634-00800, Nairobi, Kenya
- Department of Pharmacology and Pharmacognosy, College of Health Sciences, University of Nairobi, 14634-00800, Nairobi, Kenya
| | - Faith A Okalebo
- Department of Pharmacology and Pharmacognosy, College of Health Sciences, University of Nairobi, 14634-00800, Nairobi, Kenya
| | - Solomon Derese
- Department of Chemistry, University of Nairobi, 30197-00100, Nairobi, Kenya
| | - Joseph Muriuki
- Centre for Virus Research, Kenya Medical Research Institute, 54628-00200, Nairobi, Kenya
| | - Winnie Rotich
- Sigowet-Soin Sub-County Hospital, Sondu-Kapsoit Road, Sigowet, Kericho County, 112-20200, Kericho, Kenya
| | - Eduard Mas-Claret
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey, TW9 3AE, U.K
| | - Nicholas Sadgrove
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey, TW9 3AE, U.K
| | | | | | - Holly Siddique
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey, TW9 3AE, U.K
| | - Moses K Langat
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey, TW9 3AE, U.K
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Koch H, Welcome V, Kendal-Smith A, Thursfield L, Farrell IW, Langat MK, Brown MJF, Stevenson PC. Host and gut microbiome modulate the antiparasitic activity of nectar metabolites in a bumblebee pollinator. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210162. [PMID: 35491601 PMCID: PMC9058528 DOI: 10.1098/rstb.2021.0162] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Antimicrobial nectar secondary metabolites can support pollinator health by preventing or reducing parasite infections. To better understand the outcome of nectar metabolite-parasite interactions in pollinators, we determined whether the antiparasitic activity was altered through chemical modification by the host or resident microbiome during gut passage. We investigated this interaction with linden (Tilia spp.) and strawberry tree (Arbutus unedo) nectar compounds. Unedone from A. unedo nectar inhibited the common bumblebee gut parasite Crithidia bombi in vitro and in Bombus terrestris gynes. A compound in Tilia nectar, 1-[4-(1-hydroxy-1-methylethyl)-1,3-cyclohexadiene-1-carboxylate]-6-O-β-d-glucopyranosyl-β-d-glucopyranose (tiliaside), showed no inhibition in vitro at naturally occurring concentrations but reduced C. bombi infections of B. terrestris workers. Independent of microbiome status, tiliaside was deglycosylated during gut passage, thereby increasing its antiparasitic activity in the hindgut, the site of C. bombi infections. Conversely, unedone was first glycosylated in the midgut without influence of the microbiome to unedone-8-O-β-d-glucoside, rendering it inactive against C. bombi, but subsequently deglycosylated by the microbiome in the hindgut, restoring its activity. We therefore show that conversion of nectar metabolites by either the host or the microbiome modulates antiparasitic activity of nectar metabolites. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.
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Affiliation(s)
- Hauke Koch
- Royal Botanic Gardens Kew, Kew Green, Richmond, Surrey TW9 3AE, UK
| | - Vita Welcome
- Royal Botanic Gardens Kew, Kew Green, Richmond, Surrey TW9 3AE, UK.,Imperial College, South Kensington, London SW7 2BX, UK
| | - Amy Kendal-Smith
- Royal Botanic Gardens Kew, Kew Green, Richmond, Surrey TW9 3AE, UK.,Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, UK
| | - Lucy Thursfield
- Royal Botanic Gardens Kew, Kew Green, Richmond, Surrey TW9 3AE, UK.,John Innes Centre, Norwich, Norfolk NR4 7UH, UK
| | - Iain W Farrell
- Royal Botanic Gardens Kew, Kew Green, Richmond, Surrey TW9 3AE, UK
| | - Moses K Langat
- Royal Botanic Gardens Kew, Kew Green, Richmond, Surrey TW9 3AE, UK
| | - Mark J F Brown
- Centre for Ecology, Evolution and Behaviour, Department of Biological Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
| | - Philip C Stevenson
- Royal Botanic Gardens Kew, Kew Green, Richmond, Surrey TW9 3AE, UK.,Natural Resources Institute, University of Greenwich, Greenwich, Kent ME4 4TB, UK
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Essombe Malolo FA, Bellier Tabekoueng G, Dongmo Tekapi Tsopgni W, Nguemdjo Chimeze VW, Kenmogne Kouam A, Mas-Claret E, Langat MK, Ndom JC, Frese M, Sewald N, Duplex Wansi J. Chemical Constituents of the Stem Bark of the Hybrid Plant Citrus × paradisi Macfad. (Rutaceae). Chem Biodivers 2022; 19:e202101033. [PMID: 35678514 DOI: 10.1002/cbdv.202101033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 05/17/2022] [Indexed: 11/06/2022]
Abstract
The stem bark of Citrus × paradisi Macfad. (Rutaceae) gave (23S)-isolimonexic acid (1), limonin (2), citracridone II (3), citpressine II (4), citpressine I (5), grandisine (6), 2-hydroxynoracronycine (7), citracridone I (8), 5-methoxyseselin (9), umbelliferone (10), scopoletin (11), naringenin (12), apigenin (13), friedelin (14), agrostophyllinone (15) and stigmasterol-3-O-β-D-glucopyranoside (16). The structures of the compounds were determined using NMR and MS spectroscopic data, and by comparison with published data. The relative configuration of 1 was proposed as (23S)-isolimonexic acid using NOE studies. Hydrogenation reaction of compound 3 led to the new derivative 3',4'-dihydrocitracridone II (3a). Cytotoxicity activities against the human adenocarcinoma alveolar basal epithelial cell lines A549 and the Caucasian prostate adenocarcinoma cell lines PC3, using the MTT assays showed that the methanol crude extract was significant with IC50 values of 30.1 and 31.7 μg/mL, respectively, with the positive control, doxorubicin giving an IC50 of 0.9 μM. In addition, compounds 3, 7 and 8 gave moderate cytotoxic activities with IC50 values of 33.1, 31.2 and 32.5 μM for A549 cells and 35.7, 33.8 and 34.9 μM for PC3 cells, respectively. The hydrogenated 3a was less active than 3, suggesting that the presence of the double bond in pyrans is important for structure-activity relationship.
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Affiliation(s)
| | - George Bellier Tabekoueng
- Department of Chemistry, Faculty of Sciences, University of Douala, P.O. Box 24157, Douala, Cameroon
| | | | | | - Ariane Kenmogne Kouam
- Department of Chemistry, Faculty of Sciences, University of Douala, P.O. Box 24157, Douala, Cameroon
| | - Eduard Mas-Claret
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey, TW9 3AE, UK
| | - Moses K Langat
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey, TW9 3AE, UK
| | - Jean Claude Ndom
- Department of Chemistry, Faculty of Sciences, University of Douala, P.O. Box 24157, Douala, Cameroon
| | - Marcel Frese
- Organic and Bioorganic Chemistry, Department of Chemistry, Bielefeld University, 33501, Bielefeld, Germany
| | - Norbert Sewald
- Organic and Bioorganic Chemistry, Department of Chemistry, Bielefeld University, 33501, Bielefeld, Germany
| | - Jean Duplex Wansi
- Department of Chemistry, Faculty of Sciences, University of Douala, P.O. Box 24157, Douala, Cameroon.,Organic and Bioorganic Chemistry, Department of Chemistry, Bielefeld University, 33501, Bielefeld, Germany
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Kemboi D, Langat MK, Siwe-Noundou X, Krause RWM, Isaacs ML, Tembu VJ. In vitro antibacterial and cytotoxic effects of Euphorbia grandicornis Blanc chemical constituents. BMC Complement Med Ther 2022; 22:90. [PMID: 35337309 PMCID: PMC8957186 DOI: 10.1186/s12906-022-03571-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 03/14/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Euphorbia grandicornis is widely utilized in traditional medicine for the treatment of microbial infections including sexually transmitted diseases such as syphilis, gonorrhoea and for healing of wounds. OBJECTIVE The aim of this work was to isolate and evaluate the antibacterial and anticancer activities of Euphorbia grandicornis chemical constituents. METHODS Chemical constituents were isolated and identified using various spectroscopic techniques such as IR, MS, and NMR. The single point growth inhibitory potential of the compounds was determined using a 96-well plate based assay. RESULTS The CH2Cl2 crude extracts exhibited potent antibacterial activity against Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 6538 with percentage growth of 94.90 ± 4.24 and 29.47 ± 4.89 respectively. Hence, the CH2Cl2 crude extract was further subjected to column chromatography which resulted in the isolation of methyl 2,5-dihydroxybenzoate (1), n-octyl benzoate (2), friedelanol (3), and germanicol (4) and identification of compounds 12-24 for the first time in the species based on the LC-MS/MS spectroscopic data. The purified compounds (1-4), and previously reported compounds (5-11) were evaluated for antibacterial activities against S. aureus and E. coli, as well as the cytotoxicity effects against HeLa cells. Of the purified compounds, methyl 2,5-dihydroxybenzoate (1), was the most active against E.coli and S. aureus with a percentage growth of 19.12 ± 0.65 and 23.32 ± 0.23 respectively. β-amyrin (6), and β-sitosterol (8), were active against S. aureus with percentage growth of 27.17 ± 0.07, and 47.79 ± 2.99 respectively. CONCLUSION The results obtained from this study indicate that E. grandicornis, is a rich source of chemical constituents that may provide new lead compounds for the development of antibacterial agents.
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Affiliation(s)
- Douglas Kemboi
- Department of Chemistry, Tshwane University of Technology, Pretoria, 0001, South Africa. .,Department of Chemistry, Rhodes University, Makhanda (Grahamstown), 6140, South Africa.
| | - Moses K Langat
- Royal Botanic Gardens Kew, Kew Green, Richmond, Surrey, TW9 3AE, UK
| | - Xavier Siwe-Noundou
- Pharmaceutical Sciences Department, School of Pharmacy, Sefako Makgatho Health Sciences University, Pretoria, 0204, South Africa
| | - Rui W M Krause
- Department of Chemistry, Rhodes University, Makhanda (Grahamstown), 6140, South Africa
| | - Michelle Louise Isaacs
- Department of Biochemistry and Microbiology, Rhodes University, Makhanda (Grahamstown),, 6140, South Africa
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11
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Ngah L, Tsopgni WDT, Nyobe JCN, Tcho AT, Langat MK, Ndom JC, Mas-Claret E, Sadgrove NJ, Waffo AFK, Phumthum M. A New Antimicrobial Phenylpropanol from the Leaves of Tabernaemontana inconspicua Stapf. (Apocynaceae) Inhibits Pathogenic Gram-Negative Bacteria. Antibiotics (Basel) 2022; 11:antibiotics11010121. [PMID: 35052998 PMCID: PMC8773313 DOI: 10.3390/antibiotics11010121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 11/21/2022] Open
Abstract
A chemical investigation of the leaves of Tabernaemontana inconspicua Stapf. led to the isolation of a new phenylpropanol derivative, namely irisdichototin G (1), together with nine known compounds, including one polyol derivative, dambonitol (2); three alkaloids, 10-hydroxycoronaridine (3), voacristine (4) and vobasine (5); two triterpenes lupeol (6), betulinic acid (7) and three sterols, sitosterol (8), sitosterol-3-O-β-D-glucopyranoside (9) and stigmasterol (10). The structure of the new compound, as well as those of the known ones, was established by means of spectroscopic methods: NMR analysis (1H and 13C NMR, 1H-1H-COSY, HSQC, HMBC and NOESY), high-resolution mass spectrometry (HR-ESI-MS) and comparisons with previously reported data. Among the known compounds, compound 2 was firstly reported from the family Apocynaceae. Compounds 1–5 were tested for their antimicrobial effects against three Gram-negative organisms associated with human wound and systemic infections, namely Haemophilus influenzae 9435337A, Klebsiella pneumoniae 17102005 and Pseudomonas aeruginosa 2137659B. Compounds 1, 3, and 5 showed significant antimicrobial effects with minimum inhibitory concentrations (MIC) of 62.5 μg/mL, 62.5 μg/mL and 7.81 μg/mL, respectively, against Haemophilus influenzae, whereas compounds 1 and 5 showed significant antimicrobial effects, with a MIC value of 31.25 μg/mL against Pseudomonas aeruginosa. In addition, compound 3 showed significant antimicrobial activity, with a MIC value of 31.25 μg/mL against Klebsiella pneumoniae.
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Affiliation(s)
- Lidwine Ngah
- Faculty of Sciences, Department of Chemistry, University of Douala, Douala P.O. Box 24157, Cameroon; (L.N.); (W.D.T.T.); (J.C.N.); (A.F.K.W.)
| | - Willifred Dongmo Tékapi Tsopgni
- Faculty of Sciences, Department of Chemistry, University of Douala, Douala P.O. Box 24157, Cameroon; (L.N.); (W.D.T.T.); (J.C.N.); (A.F.K.W.)
| | - Judith Caroline Ngo Nyobe
- Laboratory of Quality Control for Food, Pharmaceutical and Cosmetic Products, Department of Thermal Engineering and Energy, University Institute of Technology, University of Douala, Douala P.O. Box 8698, Cameroon;
| | - Alain Tadjong Tcho
- Department of Chemistry, Faculty of Sciences, University of Buea, Buea P.O. Box 63, Cameroon;
| | - Moses K. Langat
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey TW9 3AE, UK; (M.K.L.); (E.M.-C.); (N.J.S.)
| | - Jean Claude Ndom
- Faculty of Sciences, Department of Chemistry, University of Douala, Douala P.O. Box 24157, Cameroon; (L.N.); (W.D.T.T.); (J.C.N.); (A.F.K.W.)
| | - Eduard Mas-Claret
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey TW9 3AE, UK; (M.K.L.); (E.M.-C.); (N.J.S.)
| | - Nicholas John Sadgrove
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey TW9 3AE, UK; (M.K.L.); (E.M.-C.); (N.J.S.)
| | - Alain François Kamdem Waffo
- Faculty of Sciences, Department of Chemistry, University of Douala, Douala P.O. Box 24157, Cameroon; (L.N.); (W.D.T.T.); (J.C.N.); (A.F.K.W.)
| | - Methee Phumthum
- Royal Botanic Gardens, Kew, Kew Green, Richmond, Surrey TW9 3AE, UK; (M.K.L.); (E.M.-C.); (N.J.S.)
- Department of Pharmaceutical Botany, Faculty of Pharmacy, Mahidol University, Bangkok 10400, Thailand
- Correspondence:
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Magozwi DK, Peter X, Langat MK, Mhlanga R, Vukea N, Mare JADL, Siwe-Noundou X, Krause RW, Tembu VJ. In vitro cytotoxic effects of chemical constituents of Euphorbia grandicornis Blanc against breast cancer cells. Scientific African 2021. [DOI: 10.1016/j.sciaf.2021.e01002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
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Padilla-González GF, Sadgrove NJ, Rosselli A, Langat MK, Fang R, Simmonds MSJ. Cyanogenic Derivatives as Chemical Markers for the Authentication of Commercial Products of Bamboo Shoots. J Agric Food Chem 2021; 69:9915-9923. [PMID: 34425053 DOI: 10.1021/acs.jafc.1c02947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The authentication of bamboo shoots found in the marketplace is complex because the chemical profile of processed and unprocessed material is different. During processing, heat derivatives of the potentially toxic cyanogenic glycoside taxiphyllin are produced. Here, we report the isolation and structure elucidation of the two major diarylbutenedinitrile derivatives, which are cis and trans isomers of the rare 2,3-bis(4-hydroxyphenyl)but-2-enedinitrile from a commercial extract of bamboo shoots. These compounds, absent in fresh bamboo shoots, were produced by boiling the shoots of Bambusa vulgaris and were associated with a decrease in levels of taxiphyllin. Furthermore, (E)-2,3-bis(4-hydroxyphenyl)but-2-enedinitrile was quantified in all 16 of the commercial products tested. Its abundance was found to be highly variable, ranging from 1 to 3 mg/g in preserved bamboo shoots and from 10 to 160 mg/mL in commercial aqueous extracts. Of the 15 authenticated bamboo samples tested for taxiphyllin, it was found only in the shoots of B. vulgaris and Gigantochloa verticillata, which represent two edible bamboo species. Our results indicate that diarylbutenedinitriles can be used as markers for the authentication of boil-processed bamboo shoots obtained from taxiphyllin-containing edible species and organs.
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Affiliation(s)
| | | | | | - Moses K Langat
- Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, U.K
| | - Rui Fang
- Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, U.K
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Kemboi D, Siwe-Noundou X, Krause RWM, Langat MK, Tembu VJ. Euphorbia Diterpenes: An Update of Isolation, Structure, Pharmacological Activities and Structure-Activity Relationship. Molecules 2021; 26:5055. [PMID: 34443641 PMCID: PMC8399488 DOI: 10.3390/molecules26165055] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/12/2021] [Accepted: 08/16/2021] [Indexed: 01/22/2023] Open
Abstract
Euphorbia species have a rich history of ethnomedicinal use and ethnopharmacological applications in drug discovery. This is due to the presence of a wide range of diterpenes exhibiting great structural diversity and pharmacological activities. As a result, Euphorbia diterpenes have remained the focus of drug discovery investigations from natural products. The current review documents over 350 diterpenes, isolated from Euphorbia species, their structures, classification, biosynthetic pathways, and their structure-activity relationships for the period covering 2013-2020. Among the isolated diterpenes, over 20 skeletal structures were identified. Lathyrane, jatrophane, ingenane, ingenol, and ingol were identified as the major diterpenes in most Euphorbia species. Most of the isolated diterpenes were evaluated for their cytotoxicity activities, multidrug resistance abilities, and inhibitory activities in vitro, and reported good activities with significant half-inhibitory concentration (IC50) values ranging from 10-50 µM. The lathyranes, isopimaranes, and jatrophanes diterpenes were further found to show potent inhibition of P-glycoprotein, which is known to confer drug resistance abilities in cells leading to decreased cytotoxic effects. Structure-activity relationship (SAR) studies revealed the significance of a free hydroxyl group at position C-3 in enhancing the anticancer and anti-inflammatory activities and the negative effect it has in position C-2. Esterification of this functionality, in selected diterpenes, was found to enhance these activities. Thus, Euphorbia diterpenes offer a valuable source of lead compounds that could be investigated further as potential candidates for drug discovery.
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Affiliation(s)
- Douglas Kemboi
- Department of Chemistry, Faculty of Science, Tshwane University of Technology, Pretoria 0001, South Africa
- Department of Chemistry, Rhodes University, Makhanda 6140, South Africa;
| | | | - Rui W. M. Krause
- Department of Chemistry, Rhodes University, Makhanda 6140, South Africa;
| | - Moses K. Langat
- Jodrell Laboratory, Department of Unlocking Properties, Royal Botanic Gardens Kew, Richmond TW9 3DS, UK;
| | - Vuyelwa Jacqueline Tembu
- Department of Chemistry, Faculty of Science, Tshwane University of Technology, Pretoria 0001, South Africa
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Tsamo AT, Fodja Saah EP, Langat MK, Mkounga P, Kamdem Waffo AF, Nkengfack AE. Antimycobacterial cycloartane derivatives from the roots of Trichilia welwistchii C. DC (Meliaceae). Zeitschrift für Naturforschung B 2021. [DOI: 10.1515/znb-2021-0060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Chemical investigation of the roots of Trichilia welwitschii yielded a cycloartane type terpenoid 28,29-bis-norcycloart-24-en-3β,4α,6α-triol (1), isolated as pure compound for the first time, three coumarins and three sterols. New cycloartane derivatives (1a) and (1b+1c) were obtained by hemi-synthetic reaction of compound 1. The structures of 1a–c were established by spectroscopic methods including 1D and 2D-NMR analysis, HR-EIMS, chemical transformations and by comparison of these data with those of related compounds. Evaluated for their antimycobacterial potential, compound 1 and 1b+1c were determined to show significant activities against Mycobacterium tuberculosis MIC values of 6.25 μg mL−1 while compound 1a displayed weak activity showing MIC > 100 μg mL−1. Compounds 2–4 displayed moderate activity with MIC values range from 12.5 to 50 μg mL−1.
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Affiliation(s)
- Armelle Tontsa Tsamo
- Department of Organic Chemistry , University of Yaoundé I , P. O. Box 812 , Yaoundé , Cameroon
| | - Edwige P. Fodja Saah
- Department of Organic Chemistry , Faculty of Science, University of Yaoundé I , P. O. Box 812 , Yaoundé , Cameroon
| | - Moses K. Langat
- Jodrell Laboratory , Natural Capital and Plant Health , Royal Botanic Gardens, Kew , Richmond , TW9 3DS , UK
- Department of Chemistry , Faculty of Engineering and Physical Sciences, University of Surrey , Guildford , Surrey GU2 7XH , UK
| | - Pierre Mkounga
- Department of Organic Chemistry , Faculty of Science, University of Yaoundé I , P. O. Box 812 , Yaoundé , Cameroon
| | | | - Augustin Ephrem Nkengfack
- Department of Organic Chemistry , Faculty of Science, University of Yaoundé I , P. O. Box 812 , Yaoundé , Cameroon
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Sadgrove NJ, Padilla-González GF, Green A, Langat MK, Mas-Claret E, Lyddiard D, Klepp J, Legendre SVAM, Greatrex BW, Jones GL, Ramli IM, Leuner O, Fernandez-Cusimamani E. The Diversity of Volatile Compounds in Australia's Semi-Desert Genus Eremophila (Scrophulariaceae). Plants (Basel) 2021; 10:plants10040785. [PMID: 33923613 PMCID: PMC8073941 DOI: 10.3390/plants10040785] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/09/2021] [Accepted: 04/13/2021] [Indexed: 12/20/2022]
Abstract
Australia’s endemic desert shrubs are commonly aromatic, with chemically diverse terpenes and phenylpropanoids in their headspace profiles. Species from the genus Eremophila (Scrophulariaceae ex. Myoporaceae) are the most common, with 215 recognised taxa and many more that have not yet been described, widely spread across the arid parts of the Australian continent. Over the years, our research team has collected multiple specimens as part of a survey to investigate the chemical diversity of the genus and create leads for further scientific enquiry. In the current study, the diversity of volatile compounds is studied using hydrodistilled essential oils and leaf solvent extracts from 30 taxa. Several rare terpenes and iridoids were detected in chemical profiles widely across the genus, and three previously undescribed sesquiterpenes were isolated and are assigned by 2D NMR—E-11(12)-dehydroisodendrolasin, Z-11-hydroxyisodendrolasin and 10-hydroxydihydro-α-humulene acetate. Multiple sampling from Eremophila longifolia, Eremophila arbuscular, Eremophila latrobei, Eremophila deserti, Eremophila sturtii, Eremophila oppositifolia and Eremophila alternifolia coneys that species in Eremophila are highly chemovariable. However, taxa are generally grouped according to the expression of (1) furanosesquiterpenes, (2) iridoids or oxides, (3) mixtures of 1 and 2, (4) phenylpropanoids, (5) non-furanoid terpenes, (6) mixtures of 4 and 5, and less commonly (7) mixtures of 1 and 5. Furthermore, GC–MS analysis of solvent-extracted leaves taken from cultivated specimens conveys that many heavier ‘volatiles’ with lower vapour pressure are not detected in hydrodistilled essential oils and have therefore been neglected in past chemical studies. Hence, our data reiterate that chemical studies of the genus Eremophila will continue to describe new metabolites and that taxon determination has limited predictive value for the chemical composition.
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Affiliation(s)
- Nicholas J. Sadgrove
- Jodrell Science Laboratory, Royal Botanic Gardens Kew, Richmond TW9 3DS, UK; (G.F.P.-G.); (A.G.); (M.K.L.); (E.M.-C.)
- Correspondence: (N.J.S.); (E.F.-C.); Tel.: +44-785-756-9823 (N.J.S.); +420-224-382-183 (E.F.-C.)
| | - Guillermo F. Padilla-González
- Jodrell Science Laboratory, Royal Botanic Gardens Kew, Richmond TW9 3DS, UK; (G.F.P.-G.); (A.G.); (M.K.L.); (E.M.-C.)
| | - Alison Green
- Jodrell Science Laboratory, Royal Botanic Gardens Kew, Richmond TW9 3DS, UK; (G.F.P.-G.); (A.G.); (M.K.L.); (E.M.-C.)
| | - Moses K. Langat
- Jodrell Science Laboratory, Royal Botanic Gardens Kew, Richmond TW9 3DS, UK; (G.F.P.-G.); (A.G.); (M.K.L.); (E.M.-C.)
| | - Eduard Mas-Claret
- Jodrell Science Laboratory, Royal Botanic Gardens Kew, Richmond TW9 3DS, UK; (G.F.P.-G.); (A.G.); (M.K.L.); (E.M.-C.)
| | - Dane Lyddiard
- School of Science and Technology and School of Rural Medicine, University of New England, Armidale, NSW 2351, Australia; (D.L.); (J.K.); (S.V.A.-M.L.); (B.W.G.); (G.L.J.); (I.M.R.)
| | - Julian Klepp
- School of Science and Technology and School of Rural Medicine, University of New England, Armidale, NSW 2351, Australia; (D.L.); (J.K.); (S.V.A.-M.L.); (B.W.G.); (G.L.J.); (I.M.R.)
| | - Sarah V. A.-M. Legendre
- School of Science and Technology and School of Rural Medicine, University of New England, Armidale, NSW 2351, Australia; (D.L.); (J.K.); (S.V.A.-M.L.); (B.W.G.); (G.L.J.); (I.M.R.)
| | - Ben W. Greatrex
- School of Science and Technology and School of Rural Medicine, University of New England, Armidale, NSW 2351, Australia; (D.L.); (J.K.); (S.V.A.-M.L.); (B.W.G.); (G.L.J.); (I.M.R.)
| | - Graham L. Jones
- School of Science and Technology and School of Rural Medicine, University of New England, Armidale, NSW 2351, Australia; (D.L.); (J.K.); (S.V.A.-M.L.); (B.W.G.); (G.L.J.); (I.M.R.)
| | - Iskandar M. Ramli
- School of Science and Technology and School of Rural Medicine, University of New England, Armidale, NSW 2351, Australia; (D.L.); (J.K.); (S.V.A.-M.L.); (B.W.G.); (G.L.J.); (I.M.R.)
| | - Olga Leuner
- Department of Crop Sciences and Agroforestry, Faculty of Tropical AgriSciences, Czech University of Life Sciences Prague, Kamýcká 129, 16500 Prague, Czech Republic;
| | - Eloy Fernandez-Cusimamani
- Department of Crop Sciences and Agroforestry, Faculty of Tropical AgriSciences, Czech University of Life Sciences Prague, Kamýcká 129, 16500 Prague, Czech Republic;
- Correspondence: (N.J.S.); (E.F.-C.); Tel.: +44-785-756-9823 (N.J.S.); +420-224-382-183 (E.F.-C.)
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Abstract
The bulbs of the South African Drimia altissima (Asparagaceae or Hyacinthaceae sensu APGII) have yielded a range of previously undescribed bufadienolides, drimianins A-G (1-7), the known bufadienolides bovogenin A (8), 3β-O-β-d-glucopyranosylbovogenin A (9), scillaren F (10), and altoside (11), the known homoisoflavonoid (3S)-3-(4'-methoxybenzyl)-5,6,7-trimethoxychroman-4-one (urgineanin C), the sesquiterpenoids 1β,6α-dihydroxy-4(15)-eudesmene and 6α-hydroxy-4(15)-eudesmen-1-one, polybotrin, adenosine, and 9R-hydroxy-(10E,12Z)-octadecadienoic acid ethyl ester. The bufadienolides isolated were tested at 10 μM in the NCI-60 cancer cell screen, and nine of these were selected for further screening at five concentrations. Drimianins C (3) and E (5) showed activity at the nanomolar level against a number of human cancer cell lines in the NCI-60 screen.
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Affiliation(s)
- Linda Langat
- Natural Products Research Group, Department of Chemistry, University of Surrey, Guildford, GU2 7XH, United Kingdom
| | - Moses K Langat
- Natural Products Research Group, Department of Chemistry, University of Surrey, Guildford, GU2 7XH, United Kingdom
- Department of Chemistry, University of KwaZulu-Natal, Durban, 4041, South Africa
| | | | - Walter Knirsch
- Institute of Biology, NAWI Graz, University of Graz, 8010 Graz, Austria
| | - Dulcie A Mulholland
- Natural Products Research Group, Department of Chemistry, University of Surrey, Guildford, GU2 7XH, United Kingdom
- Department of Chemistry, University of KwaZulu-Natal, Durban, 4041, South Africa
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Langat MK, Mayowa Y, Sadgrove N, Danyaal M, Prescott TAK, Kami T, Schwikkard S, Barker J, Cheek M. Multi-layered antimicrobial synergism of ( E)-caryophyllene with minor compounds, tecleanatalensine B and normelicopine, from the leaves of Vepris gossweileri (I. Verd.) Mziray. Nat Prod Res 2021; 36:2447-2457. [PMID: 33719772 DOI: 10.1080/14786419.2021.1899176] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
An aromatic alkaloid-rich 'absolute' extract from Vepris gossweileri inhibited Saccharomyces cerevisiae at 62.5 μg.mL-1 and Bacillus subtilis at 500 μg.mL-1. A loss of activity upon fractionation indicated possible synergistic effects. Three new acridones, gossweicridone A (3), B (4) and C (5) and known compounds from the extract were inactive. Combinations of compounds showed that a sub-fraction containing mixtures of minor compounds with (Ε)-caryophyllene augmented activity by 50-folds, with MIC values of 19.6 μg.mL-1 for S. cerevisiae and 375.0 μg.mL-1 for B. subtilis, demonstrating potent ΣFIC values of 0.02 and 0.375 respectively. From the active sub-fraction, three compounds were assigned as tecleanatalensine B, 13S-hydroxy-9Z,11E,15E-octadecatrienoic acid and normelicopine. In combination with (Ε)-caryophyllene they separately demonstrated MIC values of 18 μg.mL-1, 34 μg.mL-1 and 16 μg.mL-1, respectively against S. cerevisiae. The synergistic combinations were more potent with addition of pheophytin A, suggesting that the synergistic antifungal effect of the extract is multi-layered.
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Affiliation(s)
- Moses K Langat
- Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, UK
| | - Yisau Mayowa
- Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, UK
| | - Nicholas Sadgrove
- Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, UK
| | - Mohammed Danyaal
- Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, UK.,School of Life Sciences, Pharmacy and Chemistry, Kingston University, London, UK
| | - Thomas A K Prescott
- Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, UK
| | - Teva Kami
- Herbier National, Institut National en Sciences Exactes et Naturelles, (IRSEN), Cité Scientifique de Brazzaville, Brazzaville, République du Congo
| | - Sianne Schwikkard
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, London, UK
| | - James Barker
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, London, UK
| | - Martin Cheek
- Identification and Naming Department, Herbarium, Royal Botanic Gardens, Richmond, Surrey, UK
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Langat MK, Dlova NC, Mulcahy-Ryan LE, Schwikkard SL, Opara EI, Crouch NR, Hiles JD, Mulholland DA. The effect of isolates from Cassipourea flanaganii (Schinz) alston, a plant used as a skin lightning agent, on melanin production and tyrosinase inhibition. J Ethnopharmacol 2021; 264:113272. [PMID: 32810622 DOI: 10.1016/j.jep.2020.113272] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 03/19/2020] [Accepted: 07/05/2020] [Indexed: 06/11/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The Zulu and Xhosa people of South Africa use the stem bark of Cassipourea flanaganii as a skin-lightning cosmetic. AIM OF THE STUDY To isolate and identify compounds responsible for the skin lightning properties from the stem bark of Cassipourea flanaganii and to evaluate their cytotoxicity towards skin cells. MATERIALS AND METHODS Extracts from the stem bark of Cassipourea flanaganii were isolated using chromatographic methods and structures were determined using NMR, IR and MS analysis. The tyrosinase inhibitory activity and the ability to inhibit the production of melanin were determined using human primary epidermal melanocyte cells. Cytoxicity was established using the same melanocytes and a neutral red assay. RESULTS One previously undescribed compound, ent-atis-16-en-19-al (1) along with the known ent-atis-16-en-19-oic acid (2), ent-atis-16-en-19-ol (3), ent-kaur-16-en-19-oic acid (4), ent-kaur-16-en-19-al (5), ent-manoyl oxide (6), guinesine A (7), guinesine B (8), guinesine C (9), lichenxanthone (10), 2,4-dihydroxy-3,6-dimethyl benzoic acid methyl ester (11), lynoside (12), lupeol (13), β-amyrin (14), docosyl ferulate (15), stigmasterol, sitosterol and sitosterol-O-glucoside were isolated in this investigation. An impure fraction containing compound 3 was acetylated to obtain 19-acetoxy-ent-atis-16-ene (3a). Compounds 10 and 11 are usually isolated from lichen, hence they are possible contaminants of lichen harvested with the bark. Compounds 1, 3a, 5-14 were not significantly cytotoxic to the primary epidermal melanocyte cells (P > 0.05) when compared to the negative and positive controls (DMSO, 0.1% and hydrogen peroxide, 30 wt% in water). Inhibition of tyrosinase was significantly greater with respect to the negative control (P < 0.001) for compounds 3a, 5-8 and 9-10 at 10 μM and for compounds 5-8 and 9-10 at 100 μM. Compared to hydroquinone (the positive control) at 10 μM, the level of inhibition was comparable or to that of compounds 3a, 5, 6, and 8-10 at 10 μM, with 9 and 10 showing a greater level of inhibition. Inhibition of melanin was both concentration and time dependent for all compounds tested with higher melanin content at 24 h compared to 48 h s and at 10 mM compared to100 mM at both time points; melanin content was significantly lower for hydroquinone at both time points and concentrations. CONCLUSIONS Compounds 1, 5-14, isolated from Cassipourea flanaganii and the derivative 3a showed low cytotoxicity. All compounds had a clear time and concentration dependent effect on melanin content which did not appear to be dependent on their inhibition of tyrosinase.
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Affiliation(s)
- Moses K Langat
- Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3DS, United Kingdom; Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, United Kingdom; School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa.
| | - Ncoza C Dlova
- Department of Dermatology, Nelson R Mandela School of Medicine, University of KwaZulu-Natal, Private Bag X 7, Congella, 4013, Durban, South Africa
| | - Lauren E Mulcahy-Ryan
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, London, Kingston, KT1 2EE, United Kingdom
| | - Sianne L Schwikkard
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, London, Kingston, KT1 2EE, United Kingdom
| | - Elizabeth I Opara
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, London, Kingston, KT1 2EE, United Kingdom
| | - Neil R Crouch
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa; Biodiversity Research, Monitoring and Assessment, South African National Biodiversity Institute, PO Box 52099, Berea Road, 4007, Durban, South Africa
| | - Jacob D Hiles
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, United Kingdom; School of Life Sciences, Pharmacy and Chemistry, Kingston University, London, Kingston, KT1 2EE, United Kingdom
| | - Dulcie A Mulholland
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, United Kingdom; School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa
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Foster K, Oyenihi O, Rademan S, Erhabor J, Matsabisa M, Barker J, Langat MK, Kendal-Smith A, Asemota H, Delgoda R. Selective cytotoxic and anti-metastatic activity in DU-145 prostate cancer cells induced by Annona muricata L. bark extract and phytochemical, annonacin. BMC Complement Med Ther 2020; 20:375. [PMID: 33302945 PMCID: PMC7727144 DOI: 10.1186/s12906-020-03130-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 10/22/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Annona muricata L. was identified as a popular medicinal plant in treatment regimens among cancer patients in Jamaica by a previously conducted structured questionnaire. Ethnomedically used plant parts, were examined in this study against human prostate cancer cells for the first time and mechanisms of action elucidated for the most potent of them, along with the active phytochemical, annonacin. METHODS Nine extracts of varying polarity from the leaves and bark of A. muricata were assessed initially for cytotoxicity using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on PC-3 prostate cancer cells and the ethyl acetate bark (EAB) extract was identified as the most potent. EAB extract was then standardized for annonacin content using High-performance Liquid Chromatography - Mass Spectrometry (HPLC-MS) and shown to be effective against a second prostate cancer cell line (DU-145) also. The mode of cell death in DU-145 cells were assessed via several apoptotic assays including induction of increased reactive oxygen species (ROS) production, reduction of mitochondrial membrane potential, activation of caspases and annexin V externalization combined with morphological observations using confocal microscopy. In addition, the potential to prevent metastasis was examined via inhibition of cell migration, vascular endothelial growth factor (VEGF) and angiogenesis using the chorioallantoic membrane assay (CAM). RESULTS Annonacin and EAB extract displayed selective and potent cytotoxicity against the DU-145 prostate carcinoma cells with IC50 values of 0.1 ± 0.07 μM and 55.501 ± 0.55 μg/mL respectively, without impacting RWPE-1 normal prostate cells, in stark contrast to chemotherapeutic docetaxel which lacked such selectivity. Docetaxel's impact on the cancerous DU-145 was improved by 50% when used in combination with EAB extract. Insignificant levels of intracellular ROS content, depolarization of mitochondrial membrane, Caspase 3/7 activation, annexin V content, along with stained morphological evaluations, pointed to a non-apoptotic mode of cell death. The extract at 50 μg/mL deterred cell migration in the wound-healing assay, while inhibition of angiogenesis was displayed in the CAM and VEGF inhibition assays for both EAB (100 μg /mL) and annonacin (0.5 μM). CONCLUSIONS Taken together, the standardized EAB extract and annonacin appear to induce selective and potent cell death via a necrotic pathway in DU-145 cells, while also preventing cell migration and angiogenesis, which warrant further examinations for mechanistic insights and validity in-vivo.
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Affiliation(s)
- Kimberley Foster
- Natural Products Institute, University of the West Indies, Mona, Kingston 7, Jamaica
- Biotechnolgy Centre, University of the West Indies, Mona, Kingston 7, Jamaica
| | - Omolola Oyenihi
- Pharmacology Department, School of Clinical Medicine, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Sunelle Rademan
- Pharmacology Department, School of Clinical Medicine, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Joseph Erhabor
- Pharmacology Department, School of Clinical Medicine, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Motlalepula Matsabisa
- Pharmacology Department, School of Clinical Medicine, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - James Barker
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston-upon-Thames, Surrey, UK
| | - Moses K Langat
- Jodrell Laboratory, Department of Natural Capital and Plant Health, Royal Botanic Gardens, Kew, Richmond, TW9 3DS, UK
| | - Amy Kendal-Smith
- Jodrell Laboratory, Department of Natural Capital and Plant Health, Royal Botanic Gardens, Kew, Richmond, TW9 3DS, UK
- Faculty of Biological Sciences, University of Leeds, Leeds, England
| | - Helen Asemota
- Biotechnolgy Centre, University of the West Indies, Mona, Kingston 7, Jamaica
| | - Rupika Delgoda
- Natural Products Institute, University of the West Indies, Mona, Kingston 7, Jamaica.
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21
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Munissi JJE, Isyaka SM, Mas-Claret E, Brabner M, Langat MK, Nyandoro SS, Mulholland DA. Ent-clerodane and ent-trachylobane diterpenoids from Croton dictyophlebodes. Phytochemistry 2020; 179:112487. [PMID: 32847772 DOI: 10.1016/j.phytochem.2020.112487] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 08/07/2020] [Accepted: 08/10/2020] [Indexed: 06/11/2023]
Abstract
The stem bark and root bark extracts of Croton dictyophlebodes (Euphorbiaceae) yielded seven undescribed ent-clerodanes: 15,16-epoxy-17,12(S)-olide-ent-cleroda-1,3,13(16),14-tetraen-18-oic acid methyl ester (crotodictyo A), 3β,4β:15,16-diepoxy-ent-cleroda-13(16),14-dien-20-al (crotodictyo B), 3β,4β:15,16-diepoxy-ent-cleroda-13(16),14-dien-19,20-dioic acid (crotodictyo C), 3β,4β:15,16-diepoxy-ent-cleroda-13(16),14-dien-20,19-olide (crotodictyo D), 3β,4β:15,16-diepoxy-20,12(R)-olide ent-cleroda-13(16),14-dien-19-oic acid methyl ester (crotodictyo E), 15,16-epoxy-ent-cleroda-3,13(16),14-trien-12-oxo-18-oic acid (crotodictyo F) and 15,16-epoxy-ent-cleroda-1,3,13(16),14-tetraen-12-oxo-18-oic acid (crotodictyo G), in addition to 15,16-epoxy- ent-cleroda-3,13(16),14-trien-12-oxo-18-oic acid methyl ester (crotodictyo H), reported previously as a synthetic derivative, and acetyl aleuritolic acid. The root extract yielded two ent-trachylobanes, ent-trachylobane-18,19-diol, the undescribed ent-trachylobane-2α,19-diol, along with ent-kaur-16-en-19-oic acid and 2-methoxybenzyl benzoate. Compounds were evaluated against the NCI 60 panel of human tumour cell lines at a single dose of 10-5 M, but showed no significant activity.
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Affiliation(s)
- Joan J E Munissi
- Chemistry Department, College of Natural and Applied Sciences, University of Dar es Salaam, P.O.Box 35061, Dar es Salaam, Tanzania
| | - Sani M Isyaka
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Eduard Mas-Claret
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Molly Brabner
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Moses K Langat
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK; Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3DS, United Kingdom
| | - Stephen S Nyandoro
- Chemistry Department, College of Natural and Applied Sciences, University of Dar es Salaam, P.O.Box 35061, Dar es Salaam, Tanzania.
| | - Dulcie A Mulholland
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK; School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa.
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22
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Isyaka SM, Mas-Claret E, Langat MK, Hodges T, Selway B, Mbala BM, Mvingu BK, Mulholland DA. Cytotoxic diterpenoids from the leaves and stem bark of Croton haumanianus (Euphorbiaceae). Phytochemistry 2020; 178:112455. [PMID: 32692659 DOI: 10.1016/j.phytochem.2020.112455] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/01/2020] [Accepted: 07/03/2020] [Indexed: 06/11/2023]
Abstract
The leaf extract of Croton haumanianus J. Léonard (Euphorbiaceae) yielded twenty-six compounds, including eight previously reported ent-kauranes and an ent-labdane and eight undescribed ent-kauranes, ent-16R-kauran-17-al, ent-3β-hydroxy-16R-kauran-17-al, ent-16S,17-epoxykauran-19-ol, ent-16S,17-epoxykauran-3β-ol, ent-17-palmityloxykaurane-3β,16β-diol, ent-17-palmityloxykauran-16β-ol, ent-3α,18-cyclokaurane-16β,17-diol and 19-nor-16α,17-dihydroxy-ent-kaur-4(18)-ene and three undescribed ent-clerodanes, dimethyl ent-15,16-epoxy-6β-hydroxy-1,3,13(16),14-clerodatetraen-20,12S-olide-18,19-dioate (saniolide A), dimethyl ent-15,16-epoxy-6β-hydroxy-1,3,13(16),14-clerodatetraen-20,12R-olide-18,19-dioate (12-epi-saniolide A), methyl ent-15,16-epoxy-1,3,13(16),14-clerodatetraen-18,6R:20,12S-diolide-19-oate (saniolide B). The stem bark extract yielded the ent-clerodane crotocorylifuran, and five undescribed ent-isopimaranes, ent-isopimara-8(14),15-dien-18-al, ent-18-hydroxyisopimara-8(14),15-dien-7-one, ent-isopimara-7,15-dien-18-oic acid, ent-isopimara-7,15-dien-18-ol and ent-isopimara-8,15-dien-7-oxo-18-oic acid. Three compounds, ent-kaurane-3β,16β,17-triol, ent-17-palmityloxykaurane-3β,16β-diol and ent-17-palmityloxykauran-16β-ol, showed selective activity against three of the NCI 60 cancer cell lines, the colon (HCT-116), the melanoma (M14) and the renal (786-0) cancer cell lines at a concentration of 10-5 M.
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Affiliation(s)
- Sani M Isyaka
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Eduard Mas-Claret
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Moses K Langat
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK; Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3DS, United Kingdom
| | - Thomas Hodges
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Bethany Selway
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Blaise M Mbala
- Departement de Chimie et Industry, Faculte des Sciences, Universite de Kinshasa, B.P.190 Kin XI, Democratic Republic of the Congo
| | - Bienvenu K Mvingu
- Departement de Chimie et Industry, Faculte des Sciences, Universite de Kinshasa, B.P.190 Kin XI, Democratic Republic of the Congo
| | - Dulcie A Mulholland
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK; School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa.
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23
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Bissim SM, Kenmogne SB, Lobe JS, Atangana AF, Bissoue AN, Langat MK, Isyaka SM, Lateef M, Emmanuel NH, Wansi JD, Ali MS, Waffo AFK. The chemistry and biological activities of Citrus clementina Hort. Ex Tanaka (Rutaceae), a vegetatively propagated species. Nat Prod Res 2020; 35:4839-4842. [PMID: 32091235 DOI: 10.1080/14786419.2020.1731740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
We report the chemistry and biological activities of a Cameroonian Citrus clementina Hort. Ex Tanaka, a vegetatively propagated species. The compounds isolated from this plant were determined to be the known 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone (1), tangerine (3), nobilletin (4), 5,7,8,4'-tetramethoxyflavone (5), citracridone I (6), 5-hydroxynoracronycine (7), citracridone III (8), xanthyletin (10), suberosin (9), E-suberenol (11), E-methoxysuberenol (13), 6-formylumbelliferone (12), aurantiamide acetate (2), limonin (14), stigmasterol, β-sitosterol and β-sitosterol-3-O-β-D-glucoside. The structures of the compounds were established on the basis of their NMR spectroscopic data and comparison with published data. Methanol leaf extract and compounds 1, 2, 4, 6, 7 and 10 were evaluated for their anti-inflammatory, antioxidant, urease and anti-diabetic effects. Compound 10 showed antioxidant activity, anti-inflammatory effect, urease activity and anti-diabetic activity with IC50 values of 47.3 µM, 33.5 µM, 25.2 µM and 33.9 µM respectively, values that were comparable to the respective positive standards.
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Affiliation(s)
- Samuel Magloire Bissim
- Chemistry Laboratory, Faculty of Sciences, University of Douala, Douala, Cameroon.,H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi, Pakistan
| | | | - Jules Songue Lobe
- Chemistry Laboratory, Faculty of Sciences, University of Douala, Douala, Cameroon
| | | | - Achile Nouga Bissoue
- Chemistry Laboratory, Faculty of Sciences, University of Douala, Douala, Cameroon
| | - Moses K Langat
- Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, UK
| | - Sani M Isyaka
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, UK
| | - Mehreen Lateef
- Pakistan Council of Scientific and Industrial Research, Karachi, Pakistan.,Multi-Disciplinary Research Laboratory, Bahria University Medical and Dental College, Karachi, Pakistan
| | | | - Jean Duplex Wansi
- Chemistry Laboratory, Faculty of Sciences, University of Douala, Douala, Cameroon
| | - Muhammad Shaiq Ali
- H.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences (ICCBS), University of Karachi, Karachi, Pakistan
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24
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Isyaka SM, Langat MK, Mas-Claret E, Mbala BM, Mvingu BK, Mulholland DA. Ent-abietane and ent-pimarane diterpenoids from Croton mubango (Euphorbiaceae). Phytochemistry 2020; 170:112217. [PMID: 31812109 DOI: 10.1016/j.phytochem.2019.112217] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 11/21/2019] [Accepted: 11/22/2019] [Indexed: 06/10/2023]
Abstract
Twelve ent-abietane and two ent-pimarane diterpenoids were isolated from the leaves of Croton mubango Müll. Arg. (Euphorbiaceae) collected in the Democratic Republic of the Congo. 2β-Hydroxy-ent-abieta-7,13-dien-3-one, 15-hydroxy-ent-abieta-7,13-dien-3-one, 13α,15-dihydroxy-ent-abieta-8(14)-en-3-one, 2β,9,13-trihydroxy-ent-abieta-7-en-3-one, 2β,7β-dihydroxy-ent-abieta-8,11,13-trien-3-one, 15-hydroxy-ent-abieta-8,11,13-trien-3-one and ent-pimara-8(14),15-dien-3-one and the ent-forms of the previously reported normal series diterpenoids, ent-abieta-8,11,13-trien-3-one, 7β-hydroxy-ent-abieta-8,11,13-trien-3-one, 3α-hydroxy-ent-abieta-8,11,13-triene, 15-hydroxy-ent-abieta-8,11,13-triene and 6β-hydroxy-ent-abieta-8,11,13-triene are reported here for the first time. Structures were established using HRESIMS, FTIR, NMR, DP4+ probability calculations and by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. Ent-pimara-8(14), 15-dien-3-one, showed antiproliferative activity against melanoma (MALME-3M), renal (UO-31) and ovarian cancer cell lines (IGROV1) at a concentration of 10-5 M in the NCI 60 screen.
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Affiliation(s)
- Sani M Isyaka
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Moses K Langat
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK; Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3DS, United Kingdom; School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa
| | - Eduard Mas-Claret
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK
| | - Blaise M Mbala
- Departement de Chimie et Industry, Faculte des Sciences, Universite de Kinshasa, B.P.190 Kin XI, Congo
| | - Bienvenu K Mvingu
- Departement de Chimie et Industry, Faculte des Sciences, Universite de Kinshasa, B.P.190 Kin XI, Congo
| | - Dulcie A Mulholland
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, UK; School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa.
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25
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Koch H, Woodward J, Langat MK, Brown MJ, Stevenson PC. Flagellum Removal by a Nectar Metabolite Inhibits Infectivity of a Bumblebee Parasite. Curr Biol 2019; 29:3494-3500.e5. [DOI: 10.1016/j.cub.2019.08.037] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 08/13/2019] [Accepted: 08/15/2019] [Indexed: 12/21/2022]
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26
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Takou DM, Waffo AFK, Langat MK, Wansi JD, Mulcahy-Ryan LE, Schwikkard SL, Opara EI, Mas-Claret E, Mulholland DA. Melanin Production Inhibitors from the West African Cassipourea congoensis. ACTA ACUST UNITED AC 2019. [DOI: 10.1055/a-1006-2880] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Abstract
Cassipourea congoensis (syn. Cassipourea malosana) is used in African countries as a skin-lightening agent. Two previously unreported cycloartane triterpenoids, 26-hydroxy-3-keto-24-methylenecycloartan-30-oic acid 1 and 24-methylenecycloartan-3β,26,30-triol 2 along with the known mahuannin B 3, 7-methoxymahuannin B 4, 7-methoxygeranin A 5, methyl-3-(4-hydroxy-3-methoxyphenyl)-2E-propenoate, glycerol-1-alkanoate, (E)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enal 6
, (-)-syringaresinol 7, and stigmast-5-en-3-O-β-D-glucoside, were isolated from the roots of C. congoensis. The crude extract and compounds 1 and 5 were found to inhibit the production of melanin at 10 µM with low cytotoxicity validating the ethnomedicinal use of this plant.
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Affiliation(s)
- Dieudonné M. Takou
- Department of Chemistry, Faculty of Science, University of Douala, Douala, Cameroon
| | - Alain F. Kamdem Waffo
- Department of Chemistry, Faculty of Science, University of Douala, Douala, Cameroon
- Department of Chemistry, Natural Products Research Group, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, United Kingdom
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, South Africa
| | - Moses K. Langat
- Department of Chemistry, Natural Products Research Group, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, United Kingdom
- Natural Capital and Plant Health Department, Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey, United Kingdom
| | - Jean D. Wansi
- Department of Chemistry, Faculty of Science, University of Douala, Douala, Cameroon
| | - Lauren E. Mulcahy-Ryan
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, London, Kingston, United Kingdom
| | - Sianne L. Schwikkard
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, London, Kingston, United Kingdom
| | - Elizabeth I. Opara
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, London, Kingston, United Kingdom
| | - Eduard Mas-Claret
- Department of Chemistry, Natural Products Research Group, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, United Kingdom
| | - Dulcie A. Mulholland
- Department of Chemistry, Natural Products Research Group, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, United Kingdom
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, South Africa
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27
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Tabekoueng GB, Mvot Akak C, Langat MK, Azebaze AGB, Waffo AFK, Choudhary MI, Vardamides JC. Chemical constituents from Penianthus camerounensis Dekker (Menispermaceae). Zeitschrift für Naturforschung B 2019. [DOI: 10.1515/znb-2019-0072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The phytochemical study of the roots, leaves and twigs of Penianthus camerounensis Dekker (Menispermaceae) has led to the isolation and the characterization of 20 compounds. A ceramide, camerounamide (1), and a furoclerodanediterpenoid, camerounin (2), have not been described previously, while the compounds xylopic acid (3), syringaresinol (4), iso-propylmethylcyclohexa-1,4-diol (5), 1-(28-hydroxyoctacosanoyl)glycerol (6), scoparone (7), friedelin (8), friedelanol (9) and betulinic acid (10) are being reported for the first time from the genus Penianthus alongside 10 known compounds (11–20). Chemical structures were determined using 1D- and 2D-NMR spectroscopy, MS and chemical analysis. Their chemotaxonomic importance is discussed.
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Affiliation(s)
- Georges Bellier Tabekoueng
- Department of Chemistry, Faculty of Science , University of Douala , PO Box 24157 , Douala , Cameroon
- Hussain Ebrahim Jamal Research Institute of Chemistry, University of Karachi , Karachi 75270 , Pakistan
| | - Carine Mvot Akak
- Department of Organic Chemistry, Faculty of Science , University of Yaoundé I , PO Box 812 , Yaoundé , Cameroon
| | - Moses K. Langat
- Jodrell Laboratory, Natural Capital and Plant Health Department, Royal Botanic Gardens, Kew, Richmond , Surrey TW9 3DS , UK
- Department of Chemistry , University of Surrey , Guildford, Surrey GU2 7XH , UK
| | | | | | - Muhammad Iqbal Choudhary
- Hussain Ebrahim Jamal Research Institute of Chemistry, University of Karachi , Karachi 75270 , Pakistan
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28
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Schwikkard S, Whitmore H, Sishtla K, Sulaiman RS, Shetty T, Basavarajappa HD, Waller C, Alqahtani A, Frankemoelle L, Chapman A, Crouch N, Wetschnig W, Knirsch W, Andriantiana J, Mas-Claret E, Langat MK, Mulholland D, Corson TW. The Antiangiogenic Activity of Naturally Occurring and Synthetic Homoisoflavonoids from the Hyacinthaceae ( sensu APGII). J Nat Prod 2019; 82:1227-1239. [PMID: 30951308 PMCID: PMC6771261 DOI: 10.1021/acs.jnatprod.8b00989] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Excessive blood vessel formation in the eye is implicated in wet age-related macular degeneration, proliferative diabetic retinopathy, neovascular glaucoma, and retinopathy of prematurity, which are major causes of blindness. Small molecule antiangiogenic drugs are strongly needed to supplement existing biologics. Homoisoflavonoids have been previously shown to have potent antiproliferative activities in endothelial cells over other cell types. Moreover, they demonstrated a strong antiangiogenic potential in vitro and in vivo in animal models of ocular neovascularization. Here, we tested the antiangiogenic activity of a group of naturally occurring homoisoflavonoids isolated from the family Hyacinthaceae and related synthetic compounds, chosen for synthesis based on structure-activity relationship observations. Several compounds showed interesting antiproliferative and antiangiogenic activities in vitro on retinal microvascular endothelial cells, a disease-relevant cell type, with the synthetic chromane, 46, showing the best activity (GI50 of 2.3 × 10-4 μM).
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Affiliation(s)
- Sianne Schwikkard
- School of Life Sciences, Pharmacy and Chemistry,
Kingston University, Kingston-upon-Thames, KT1 2EE, UK
- Natural Products Research Group, Department of
Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey,
Guildford, GU2 7XH, United Kingdom
| | - Hannah Whitmore
- Natural Products Research Group, Department of
Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey,
Guildford, GU2 7XH, United Kingdom
| | - Kamakshi Sishtla
- Eugene and Marilyn Glick Eye Institute, Department
of Ophthalmology, Indiana University School of Medicine, 1160 W. Michigan St.,
Indianapolis, IN 46202, U.S.A
| | - Rania S. Sulaiman
- Eugene and Marilyn Glick Eye Institute, Department
of Ophthalmology, Indiana University School of Medicine, 1160 W. Michigan St.,
Indianapolis, IN 46202, U.S.A
- Department of Pharmacology and Toxicology,
Indiana University School of Medicine, 1160 W. Michigan St., Indianapolis, IN 46202,
U.S.A
- Department of Biochemistry, Faculty of Pharmacy,
Cairo University, Cairo, Egypt
| | - Trupti Shetty
- Eugene and Marilyn Glick Eye Institute, Department
of Ophthalmology, Indiana University School of Medicine, 1160 W. Michigan St.,
Indianapolis, IN 46202, U.S.A
- Department of Pharmacology and Toxicology,
Indiana University School of Medicine, 1160 W. Michigan St., Indianapolis, IN 46202,
U.S.A
| | - Halesha D. Basavarajappa
- Eugene and Marilyn Glick Eye Institute, Department
of Ophthalmology, Indiana University School of Medicine, 1160 W. Michigan St.,
Indianapolis, IN 46202, U.S.A
- Department of Biochemistry and
Molecular Biology, Indiana University School of Medicine, 1160 W. Michigan St.,
Indianapolis, IN 46202, U.S.A
| | - Catherine Waller
- Natural Products Research Group, Department of
Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey,
Guildford, GU2 7XH, United Kingdom
| | - Alaa Alqahtani
- Natural Products Research Group, Department of
Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey,
Guildford, GU2 7XH, United Kingdom
| | - Lennart Frankemoelle
- School of Life Sciences, Pharmacy and Chemistry,
Kingston University, Kingston-upon-Thames, KT1 2EE, UK
| | - Andy Chapman
- School of Life Sciences, Pharmacy and Chemistry,
Kingston University, Kingston-upon-Thames, KT1 2EE, UK
| | - Neil Crouch
- Biodiversity Economy, South African National
Biodiversity Institute, P.O. Box 52099, 4007 Berea Road, Durban, South Africa
- School of Chemistry and Physics, University of
KwaZulu-Natal, Durban, 4041, South Africa
| | | | - Walter Knirsch
- Institute of Biology, NAWI Graz, University of Graz,
8010 Graz, Austria
| | - Jacky Andriantiana
- Parc Botanique et Zoologique de Tsimbazaza, Rue
Fernand Kassanga, Antananarivo 101, Madagascar
| | - Eduard Mas-Claret
- Natural Products Research Group, Department of
Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey,
Guildford, GU2 7XH, United Kingdom
| | - Moses K Langat
- Natural Products Research Group, Department of
Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey,
Guildford, GU2 7XH, United Kingdom
- School of Chemistry and Physics, University of
KwaZulu-Natal, Durban, 4041, South Africa
| | - Dulcie Mulholland
- Natural Products Research Group, Department of
Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey,
Guildford, GU2 7XH, United Kingdom
- School of Chemistry and Physics, University of
KwaZulu-Natal, Durban, 4041, South Africa
| | - Timothy W. Corson
- Eugene and Marilyn Glick Eye Institute, Department
of Ophthalmology, Indiana University School of Medicine, 1160 W. Michigan St.,
Indianapolis, IN 46202, U.S.A
- Department of Pharmacology and Toxicology,
Indiana University School of Medicine, 1160 W. Michigan St., Indianapolis, IN 46202,
U.S.A
- Department of Biochemistry and
Molecular Biology, Indiana University School of Medicine, 1160 W. Michigan St.,
Indianapolis, IN 46202, U.S.A
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Aziz AN, Ismail NH, Halim SNA, Looi CY, Anouar EH, Langat MK, Mulholland D, Awang K. Laevifins A-G, clerodane diterpenoids from the Bark of Croton oblongus Burm.f. Phytochemistry 2018; 156:193-200. [PMID: 30316148 DOI: 10.1016/j.phytochem.2018.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 09/30/2018] [Accepted: 10/02/2018] [Indexed: 06/08/2023]
Abstract
A phytochemical investigation of the stem barks of the Malaysian Croton oblongus Burm.f. (Syn. Croton laevifolius Blume) (Euphorbiaceae) yielded seven previously undescribed ent-neo-clerodane diterpenoids, laevifins A - G and the known crovatin (3). Structures were established by a combination of spectroscopic methods including HRESIMS, NMR spectroscopy and X-ray crystallography. The absolute configuration of crovatin and laevifins A-G was established by comparison of experimental ECD and theoretical TDDFT ECD calculated spectra. This is the first report on the occurrence of the sesquiterpenoid cryptomeridiol in a Croton species. In vitro cytotoxicity assays on laevifins A, B and G showed moderate activities against the MCF-7 cancer cell line (IC50 102, 115 and 106 μM, respectively) while β-amyrin and acetyl aleuritolic acid showed good anti-inflammatory activity on the LPS-induced NF-κB translocation inhibition in RAW 264.7 cells assay with IC50 values of 23.5 and 35.4 μg/mL, respectively.
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MESH Headings
- Animals
- Anti-Inflammatory Agents, Non-Steroidal/chemistry
- Anti-Inflammatory Agents, Non-Steroidal/isolation & purification
- Anti-Inflammatory Agents, Non-Steroidal/pharmacology
- Antineoplastic Agents, Phytogenic/chemistry
- Antineoplastic Agents, Phytogenic/isolation & purification
- Antineoplastic Agents, Phytogenic/pharmacology
- Cell Proliferation/drug effects
- Croton/chemistry
- Diterpenes, Clerodane/chemistry
- Diterpenes, Clerodane/isolation & purification
- Diterpenes, Clerodane/pharmacology
- Dose-Response Relationship, Drug
- Drug Screening Assays, Antitumor
- Humans
- Lipopolysaccharides/antagonists & inhibitors
- Lipopolysaccharides/pharmacology
- MCF-7 Cells
- Mice
- Molecular Conformation
- NF-kappa B/antagonists & inhibitors
- NF-kappa B/metabolism
- Plant Bark/chemistry
- Plant Extracts/chemistry
- Plant Extracts/isolation & purification
- Plant Extracts/pharmacology
- Quantum Theory
- RAW 264.7 Cells
- Structure-Activity Relationship
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Affiliation(s)
- Ahmad Nazif Aziz
- School of Fundamental Science, Universiti Malaysia Terengganu, 21030, Kuala Nerus, Terengganu, Malaysia; Atta-ur-Rahman Institute for Natural Products Discovery, Level 9, FF3, Universiti Teknologi MARA Puncak Alam Campus, 42300, Bandar Puncak Alam, Selangor, Malaysia
| | - Nor Hadiani Ismail
- Atta-ur-Rahman Institute for Natural Products Discovery, Level 9, FF3, Universiti Teknologi MARA Puncak Alam Campus, 42300, Bandar Puncak Alam, Selangor, Malaysia.
| | - Siti Nadiah Abdul Halim
- Department of Chemistry, Faculty of Science, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Chung Yeng Looi
- Department of Pharmacology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia; Faculty of Health and Medical Sciences, School of Biosciences, Taylor's University Lakeside Campus, 47500, Subang Jaya, Malaysia
| | - El Hassane Anouar
- Chemistry Department, College of Sciences and Humanities, Prince Sattam Bin Abdulaziz University, P.O. Box 83, 11942, Al Kharj, Saudi Arabia
| | - Moses K Langat
- Natural Products Research Group, Department of Chemistry, University of Surrey, Guildford, GU2 7XH, Surrey, United Kingdom; School of Chemistry and Physics, University of Natal, Durban, 4041, South Africa
| | - Dulcie Mulholland
- Natural Products Research Group, Department of Chemistry, University of Surrey, Guildford, GU2 7XH, Surrey, United Kingdom; School of Chemistry and Physics, University of Natal, Durban, 4041, South Africa
| | - Khalijah Awang
- Department of Chemistry, Faculty of Science, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
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30
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Langat MK, Helfenstein A, Horner C, Tammela P, Hokkanen H, Izotov D, Mulholland DA. Pumilol, a Diterpenoid with a Rare Strobane Skeleton fromPinus pumila(Pinaceae). Chem Biodivers 2018; 15:e1800056. [DOI: 10.1002/cbdv.201800056] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Accepted: 07/02/2018] [Indexed: 11/11/2022]
Affiliation(s)
- Moses K. Langat
- Natural Products Research Group; Department of Chemistry; Faculty of Engineering and Physical Sciences; University of Surrey; Guildford GU2 7XH UK
- School of Chemistry and Physics; University of KwaZulu-Natal; Durban 4041 South Africa
| | - Andreas Helfenstein
- Centre for Drug Research; Division of Pharmaceutical Biosciences; Faculty of Pharmacy; University of Helsinki; FI-00014 Helsinki Finland
| | - Claire Horner
- Natural Products Research Group; Department of Chemistry; Faculty of Engineering and Physical Sciences; University of Surrey; Guildford GU2 7XH UK
| | - Päivi Tammela
- Centre for Drug Research; Division of Pharmaceutical Biosciences; Faculty of Pharmacy; University of Helsinki; FI-00014 Helsinki Finland
| | - Heikki Hokkanen
- Department of Agricultural Sciences; University of Helsinki; FI-00014 Helsinki Finland
| | - Denis Izotov
- Sector of Biologically Active Substances; Department of Forestry; Far East Forestry Research Institute; Khabarovsk Vo-lochaevskaya 71 Russia
| | - Dulcie A. Mulholland
- Natural Products Research Group; Department of Chemistry; Faculty of Engineering and Physical Sciences; University of Surrey; Guildford GU2 7XH UK
- School of Chemistry and Physics; University of KwaZulu-Natal; Durban 4041 South Africa
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31
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Schwikkard SL, Whitmore H, Corson TW, Sishtla K, Langat MK, Carew M, Mulholland DA. Antiangiogenic Activity and Cytotoxicity of Triterpenoids and Homoisoflavonoids from Massonia pustulata and Massonia bifolia. Planta Med 2018; 84:638-644. [PMID: 29490386 PMCID: PMC6467464 DOI: 10.1055/a-0577-5322] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The Hyacinthaceae family (sensu APGII), with approximately 900 species in around 70 genera, plays a significant role in traditional medicine in Africa as well as across Europe and the Middle and Far East. The dichloromethane extract of the bulbs of Massonia pustulata (Hyacinthaceae sensu APGII) yielded two known homoisoflavonoids, (R)-5-hydroxy-3-(4-hydroxybenzyl)-7-methoxy-4-chromanone 1: and 5-hydroxy-3-(4-hydroxybenzyl)-7-methoxy-4-chromone 2: and four spirocyclic nortriterpenoids, eucosterol 3: , 28-hydroxyeucosterol 4: and two previously unreported triterpenoid derivatives, (17S,23S)-17α,23-epoxy-3β,22β,29-trihydroxylanost-8-en-27,23-olide 5: , and (17S, 23S)-17α,23-epoxy-28,29-dihydroxylanost-8-en-3-on-27,23-olide 6: . Compounds 1, 2, 3: , and 5: were assessed for cytotoxicity against CaCo-2 cells using a neutral red uptake assay. Compounds 1, 2: , and 5: reduced cell viability by 70% at concentrations of 30, 100, and 100 µM, respectively. Massonia bifolia yielded three known homoisoflavonoids, (R)-(4'-hydroxy)-5-hydroxy-7-methoxy-4-chromanone 1: , (R)-(4'-hydroxy)-5,7-dihydroxy-4-chromanone 7: and (R)-(3'-hydroxy-4'-methoxy)-5,7-dihydroxy-4-chromanone 9: , two previously unreported homoisoflavonoids, (E)-3-benzylidene-(3',4'-dihydroxy)-5-hydroxy-7-methoxy-4-chromanone 8: and (R)-(3',4'-dihydroxy)-5-hydroxy-7-methoxy-4-chromanone 10,: and a spirocyclic nortriterpenoid, 15-deoxoeucosterol 11: . Compounds 1, 1AC, 7, 8, 9,: and 10: were screened for antiangiogenic activity against human retinal microvascular endothelial cells. Some compounds showed dose-dependent antiproliferative activity and blocked endothelial tube formation, suggestive of antiangiogenic activity.
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Affiliation(s)
- Sianne L Schwikkard
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, Kingston-upon-Thames, United Kingdom
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, United Kingdom
| | - Hannah Whitmore
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, United Kingdom
| | - Timothy W Corson
- Eugene and Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, U. S. A
| | - Kamakshi Sishtla
- Eugene and Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, U. S. A
| | - Moses K Langat
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, United Kingdom
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, South Africa
| | - Mark Carew
- School of Life Sciences, Pharmacy and Chemistry, Kingston University, Kingston-upon-Thames, United Kingdom
| | - Dulcie A Mulholland
- Eugene and Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, U. S. A
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, South Africa
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Mangisa M, Tembu VJ, Fouche G, Nthambeleni R, Peter X, Langat MK. Ent-abietane diterpenoids from Suregada zanzibariensis Baill. (Euphorbiaceae), their cytotoxic and anticancer properties. Nat Prod Res 2018; 33:3240-3247. [PMID: 29741101 DOI: 10.1080/14786419.2018.1470628] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The stem bark extract of Suregada zanzibariensis afforded a previously undescribed ent-abietane diterpenoid trivially named mangiolide (1) and a known jolkinolide B (2) via anticancer bioassay-guided fractionation. The CH2Cl2:MeOH extract of S. zanzibariensis was initially analysed for its anticancer properties against three cancer cell lines, renal (TK10), melanoma (UACC62), and breast (MCF7) and was found to be potent at low μg/mL ranges. Compound 1, 6α-acetoxy-14-keto-ent-abieta-7(8),13(15)-diene-16,12-olide (mangiolide) inhibited the growth of renal (TK10) with a GI50 of 0.02 μg/mL; a GI50 of 0.03 μg/mL for melanoma (UACC62) and a GI50 of 0.05 μg/mL for breast (MCF7) cancer cell lines. Compound 2, 8,13-diepoxy-13,15-ent-abietene-16,12-olide (jolkinolide B) inhibited the growth (GI50) of the cell lines at 3.31 μg/mL for renal (TK10), 0.94 μg/mL for melanoma (UACC62) and 2.99 μg/mL for the breast (MCF7). The structures were established on the basis of their spectroscopic analysis and the absolute stereostructures assigned using electronic circular dichroism (ECD).
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Affiliation(s)
- Mandisa Mangisa
- Department of Chemistry, Tshwane University of Technology , Pretoria , South Africa
| | - Vuyelwa J Tembu
- Department of Chemistry, Tshwane University of Technology , Pretoria , South Africa
| | - Gerda Fouche
- Biosciences, Council for Scientific and Industrial Research , Pretoria , South Africa
| | - Rudzani Nthambeleni
- Biosciences, Council for Scientific and Industrial Research , Pretoria , South Africa
| | - Xolani Peter
- Defence, Peace, Safety and Security, Council for Scientific and Industrial Research , Pretoria , South Africa
| | - Moses K Langat
- Natural Products Research Group, Faculty of Engineering and Physical Sciences, Department of Chemistry, University of Surrey , Guildford, Surrey , UK
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Aldhaher AH, Langat MK, Knirsch W, Andriantiana JL, Mulholland DA. Isoquinoline alkaloids from three Madagascan Crinum (Amaryllidaceae) species. BIOCHEM SYST ECOL 2018. [DOI: 10.1016/j.bse.2017.12.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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34
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Thuerig B, James EE, Schärer HJ, Langat MK, Mulholland DA, Treutwein J, Kleeberg I, Ludwig M, Jayarajah P, Giovannini O, Markellou E, Tamm L. Reducing copper use in the environment: the use of larixol and larixyl acetate to treat downy mildew caused by Plasmopara viticola in viticulture. Pest Manag Sci 2018; 74:477-488. [PMID: 28905481 DOI: 10.1002/ps.4733] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/23/2017] [Accepted: 09/08/2017] [Indexed: 05/14/2023]
Abstract
BACKGROUND Plant extracts might provide sustainable alternatives to copper fungicides, which are still widely used despite their unfavourable ecotoxicological profile. Larch bark extract and its constituents, larixyl acetate and larixol, have been shown to be effective against grapevine downy mildew (Plasmopara viticola) under semi-controlled conditions. The aim of this study was to reduce the gap between innovation and the registration of a marketable product, namely to develop scalable extraction processes and to evaluate and optimise the performance of larch extracts under different conditions. RESULTS Toxicologically and technically acceptable solvents like ethanol were used to extract the active compounds larixyl acetate and larixol from bark in sufficient amounts and their combined concentration could be increased by up to 39% by purification steps. The combined concentration of larixyl acetate and larixol from larch turpentine could be increased by up to 66%. The Minimal Inhibitory Concentration (MIC100 ) against P. viticola in vitro (6-23 µg mL-1 ) and the Effective Concentration (EC50 ) in planta under semi-controlled conditions (0.2-0.4 mg mL-1 ) were promising compared with other plant extracts. In vineyards, efficacies of larch extracts reached up to 68% in a stand-alone strategy and 84% in low-copper strategies. CONCLUSION Larch extracts represent valid candidates for copper reduction in organic vineyards, and their development into a sustainable plant protection product might be feasible. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Barbara Thuerig
- Research Institute of Organic Agriculture FiBL, Frick, Switzerland
| | - Emily E James
- Natural Products Research Group, Department of Chemistry, University of Surrey, UK
| | | | - Moses K Langat
- Natural Products Research Group, Department of Chemistry, University of Surrey, UK
| | - Dulcie A Mulholland
- Natural Products Research Group, Department of Chemistry, University of Surrey, UK
| | | | | | - Mathias Ludwig
- Research Institute of Organic Agriculture FiBL, Frick, Switzerland
| | - Praveen Jayarajah
- Natural Products Research Group, Department of Chemistry, University of Surrey, UK
| | - Oscar Giovannini
- Fondazione Edmund Mach di San Michele all'Adige FEM, S. Michele all'Adige, Italy
| | | | - Lucius Tamm
- Research Institute of Organic Agriculture FiBL, Frick, Switzerland
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35
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Njue AW, Omolo JO, Cheplogoi PK, Langat MK, Mulholland DA. Cytotoxic ergostane derivatives from the edible mushroom Termitomyces microcarpus (Lyophyllaceae). BIOCHEM SYST ECOL 2018. [DOI: 10.1016/j.bse.2017.11.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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36
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Waratchareeyakul W, Hellemann E, Gil RR, Chantrapromma K, Langat MK, Mulholland DA. Application of Residual Dipolar Couplings and Selective Quantitative NOE to Establish the Structures of Tetranortriterpenoids from Xylocarpus rumphii. J Nat Prod 2017; 80:391-402. [PMID: 28121439 DOI: 10.1021/acs.jnatprod.6b00906] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Nine triterpenoid derivatives were isolated from the heartwood of Xylocarpus rumphii and were identified as xylorumphiins E (1), C (2), L (3), and M-R (4-9). Compounds 4-9 have a hemiacetal group in the triterpenoid side chain, making them impossible to purify. Purification was achieved after acetylation and subsequent separation of the epimeric mixtures of acetates; however differentiaition of the R and S epimers was not possible using standard NMR techniques. In one case, the relative configuration of a remotely located stereocenter with respect to the stereocenters in the main skeleton was unambiguously determined using residual dipolar couplings. Dipolar couplings were collected from the sample oriented in compressed poly(methyl methacrylate) gels swollen in CDCl3. In another case, the relative configuration was determined using 1D selective quantitative NOE experiments. Xylorumphiin K (10), xyloccensin E, taraxer-14-en-3β-ol, (22S)-hydroxytirucalla-7,24-diene-3,23-dione, and 25-hydroxy-(20S,24S)-epoxydammaran-3-one were isolated from the bark of the same plant. Compounds 3-10 are new compounds. Compounds 1-6 and xyloccensin E were tested at one concentration, 1 × 10-5 M, in the NCI59 cell one-dose screen but did not show significant activity.
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Affiliation(s)
- Watcharee Waratchareeyakul
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey , Guildford GU2 7XH, U.K
- Department of Chemistry, Faculty of Science and Technology, Rambhai Barni Rajabhat University , Chanthaburi 22000, Thailand
| | - Erich Hellemann
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Roberto R Gil
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Kan Chantrapromma
- Faculty of Science and Technology, Hatyai University , Songkhla 90110, Thailand
| | - Moses K Langat
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey , Guildford GU2 7XH, U.K
- School of Chemistry and Physics, University of KwaZulu-Natal , Durban 4041, South Africa
| | - Dulcie A Mulholland
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey , Guildford GU2 7XH, U.K
- School of Chemistry and Physics, University of KwaZulu-Natal , Durban 4041, South Africa
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37
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Schwikkard S, Alqahtani A, Knirsch W, Wetschnig W, Jaksevicius A, Opara EI, Langat MK, Andriantiana JL, Mulholland DA. Phytochemical Investigations of Three Rhodocodon (Hyacinthaceae Sensu APG II) Species. J Nat Prod 2017; 80:30-37. [PMID: 28051316 DOI: 10.1021/acs.jnatprod.6b00240] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The genus Rhodocodon (Hyacinthaceae sensu APG II) is endemic to Madagascar, and its phytochemistry has not been described previously. The phytochemistry of three species in this genus has been investigated, and eight compounds, including three bufadienolides (compounds 1, 4, and 5), a norlignan (2), and four homoisoflavonoids (compounds 3 and 6-8), have been isolated and identified. Compounds 1-3 and 6-8 have not been described previously. The COX-2 inhibitory activity of compound 6 and compound 7 acetate (compound 7A) was investigated on isolated colorectal cancer cells. Compounds 6 and 7A inhibited COX-2 by 10% and 8%, respectively, at a concentration of 12.5 μM compared to 12% for 1 mM aspirin (the positive control).
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Affiliation(s)
- Sianne Schwikkard
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey , Guildford, GU2 7XH, United Kingdom
- School of Life Sciences, Pharmacy and Chemistry, Faculty of Science, Engineering and Computing, Kingston University , Penrhyn Road, Kingston Upon Thames, KT1 2EE, United Kingdom
| | - Alaa Alqahtani
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey , Guildford, GU2 7XH, United Kingdom
| | - Walter Knirsch
- Institute of Plant Sciences, NAWI Graz, Karl-Franzens-University Graz , Holteigasse 6, A-8010, Graz, Austria
| | - Wolfgang Wetschnig
- Institute of Plant Sciences, NAWI Graz, Karl-Franzens-University Graz , Holteigasse 6, A-8010, Graz, Austria
| | - Andrius Jaksevicius
- School of Life Sciences, Pharmacy and Chemistry, Faculty of Science, Engineering and Computing, Kingston University , Penrhyn Road, Kingston Upon Thames, KT1 2EE, United Kingdom
| | - Elizabeth I Opara
- School of Life Sciences, Pharmacy and Chemistry, Faculty of Science, Engineering and Computing, Kingston University , Penrhyn Road, Kingston Upon Thames, KT1 2EE, United Kingdom
| | - Moses K Langat
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey , Guildford, GU2 7XH, United Kingdom
- School of Chemistry and Physics, University of KwaZulu-Natal , Durban, 4041, South Africa
| | - Jackie L Andriantiana
- Parc Botanique et Zoologique de Tsimbazaza , Rue Kasanga Fernand, Antananarivo 101, Madagascar
| | - Dulcie A Mulholland
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey , Guildford, GU2 7XH, United Kingdom
- School of Chemistry and Physics, University of KwaZulu-Natal , Durban, 4041, South Africa
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38
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Sihra JK, Langat MK, Crouch NR, Nuzillard JM, Plainchont B, Mulholland DA. Novel triterpenoid derivatives from Eucomis bicolor Bak. (Hyacinthaceae: Hyacinthoideae). RSC Adv 2017. [DOI: 10.1039/c6ra28584h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The bulbs of Eucomis bicolor (Hyacinthoideae) yielded fourteen novel compounds, including (17S)-3-oxo-24,25,26,27,28-pentanorlanost-8-en-23,17α-olide, whose structure was determined using the Logic for Structure Determination Program.
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Affiliation(s)
- Jaspreet K. Sihra
- Department of Chemistry
- Faculty of Engineering and Physical Sciences
- University of Surrey
- Guildford
- UK
| | - Moses K. Langat
- Department of Chemistry
- Faculty of Engineering and Physical Sciences
- University of Surrey
- Guildford
- UK
| | - Neil R. Crouch
- School of Chemistry and Physics
- University of KwaZulu-Natal
- Durban
- South Africa
- Biodiversity Economy Unit
| | - Jean-Marc Nuzillard
- Université de Reims Champagne-Ardenne
- Institut de Chimie Moléculaire de Reims
- CNRS UMR 7312
- SFR CAP-Santé
- 51687 Reims Cedex 02
| | - Bertrand Plainchont
- Université de Reims Champagne-Ardenne
- Institut de Chimie Moléculaire de Reims
- CNRS UMR 7312
- SFR CAP-Santé
- 51687 Reims Cedex 02
| | - Dulcie A. Mulholland
- Department of Chemistry
- Faculty of Engineering and Physical Sciences
- University of Surrey
- Guildford
- UK
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Ndunda B, Langat MK, Mulholland DA, Eastman H, Jacob MR, Khan SI, Walker LA, Muhammad I, Kerubo LO, Midiwo JO. New ent-Clerodane and Abietane Diterpenoids from the Roots of Kenyan Croton megalocarpoides Friis & M. G. Gilbert. Planta Med 2016; 82:1079-1086. [PMID: 27286332 DOI: 10.1055/s-0042-108857] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The roots of the endangered medicinal plant Croton megalocarpoides collected in Kenya were investigated and twenty-two compounds isolated. Among them were twelve new ent-clerodane (1-12) and a new abietane (13) diterpenoids, alongside the known crotocorylifuran (4 a), two known abietane and four known ent-trachylobane diterpenoids, and the triterpenoids, lupeol and acetyl aleurotolic acid. The structures of the compounds were determined using NMR, HRMS and ECD. The isolated compounds were evaluated against a series of microorganisms (fungal and bacteria) and also against Plasmodium falciparum, however no activity was observed.
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Affiliation(s)
- Beth Ndunda
- Department of Chemistry, University of Nairobi, Nairobi, Kenya
| | - Moses K Langat
- Department of Chemistry, University of Surrey, Guildford, Surrey, United Kingdom
| | - Dulcie A Mulholland
- Department of Chemistry, University of Surrey, Guildford, Surrey, United Kingdom
| | - Harry Eastman
- Department of Chemistry, University of Surrey, Guildford, Surrey, United Kingdom
| | - Melissa R Jacob
- National Centre for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, MS, USA
| | - Shabana I Khan
- National Centre for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, MS, USA
| | - Larry A Walker
- National Centre for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, MS, USA
| | - Ilias Muhammad
- National Centre for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, MS, USA
| | | | - Jacob O Midiwo
- Department of Chemistry, University of Nairobi, Nairobi, Kenya
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Adjapmoh MFE, Toze FAA, Songue JL, Langat MK, Kapche GDWF, Hameed A, Lateef M, Shaiq MA, Mbaze LM, Wansi JD, Kamdem AFW. A New Ceramide and Biflavonoid from the Leaves of Parinari hypochrysea (Chrysobalanaceae). Nat Prod Commun 2016. [DOI: 10.1177/1934578x1601100515] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A new ceramide and a new biflavonoid named parinaramide (1) and sparinaritin (2), respectively, have been isolated along with ten known compounds, kaempferol, quercetin, taxifolin, taxifolin-3- O-rhamnoside, lupeol, betulinic acid, ursolic acid, 2α-hydroxy-ursolic acid, 2,3-dihydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone, and sucrose, from the leaves of Parinari hypochrysea (Chrysobalanaceae). Structures were determined using 1D- and 2D-NMR, MS and by chemical analysis. The methanol extract of leaves, stem bark and roots of P. hypochrysea were screened for their antioxidant and lipoxygenase inhibition potential and found to be inactive.
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Affiliation(s)
- Martial F. E. Adjapmoh
- Department of Chemistry, Faculty of Science, University of Douala, P.O. Box: 24157 Douala, Cameroon
- H.E.J. Research Institute of Chemistry, University of Karachi, 75270, Karachi, Pakistan
| | - Flavien A. A. Toze
- Department of Chemistry, Faculty of Science, University of Douala, P.O. Box: 24157 Douala, Cameroon
| | - Jules L. Songue
- Department of Chemistry, Faculty of Science, University of Douala, P.O. Box: 24157 Douala, Cameroon
| | - Moses K. Langat
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, United Kingdom
| | - Gilbert D. W. F. Kapche
- Department of Chemistry, Higher Teachers’ Training College, University of Yaoundé I, P.O. Box 47 Yaoundé, Cameroon
| | - Abdul Hameed
- H.E.J. Research Institute of Chemistry, University of Karachi, 75270, Karachi, Pakistan
| | - Mehreen Lateef
- Pharmaceutical Research Center, Pakistan Council of Scientific & Industrial Research Complex, Karachi, Pakistan
| | - Muhammad A. Shaiq
- H.E.J. Research Institute of Chemistry, University of Karachi, 75270, Karachi, Pakistan
| | - Luc M. Mbaze
- Department of Chemistry, Faculty of Science, University of Douala, P.O. Box: 24157 Douala, Cameroon
| | - Jean D. Wansi
- Department of Chemistry, Faculty of Science, University of Douala, P.O. Box: 24157 Douala, Cameroon
| | - Alain F. W. Kamdem
- Department of Chemistry, Faculty of Science, University of Douala, P.O. Box: 24157 Douala, Cameroon
- Natural Products Research Group, Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, GU2 7XH, United Kingdom
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Adjapmoh MFE, Toze FAA, Songue JL, Langat MK, Kapche GDWF, Hameed A, Lateef M, Shaiq MA, Mbaze LM, Wansi JD, Kamdem AFW. A New Ceramide and Biflavonoid from the Leaves of Parinari hypochrysea (Chrysobalanaceae). Nat Prod Commun 2016; 11:615-620. [PMID: 27319132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023] Open
Abstract
A new ceramide and a new biflavonoid named parinaramide (1) and sparinaritin (2), respectively, have been isolated along with ten known compounds, kaempferol, quercetin, taxifolin, taxifolin-3-O-rhamnoside, lupeol, betulinic acid, ursolic acid, 2α-hydroxy-ursolic acid, 2,3-dihydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone, and sucrose, from the leaves of Parinari hypochrysea (Chrysobalanaceae). Structures were determined using 1D- and 2D-NMR, MS and by chemical analysis. The methanol extract of leaves, stem bark and roots of P. hypochrysea were screened for their antioxidant and lipoxygenase inhibition potential and found to be inactive.
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Sihra JK, Thumser AE, Langat MK, Crouch NR, Mulholland DA. Constituents of Bulbs of three Species of the Hyacinthaceae (Hyacinthoideae): Eucomis vandermerwei, E. zambesiaca and Resnova humifusa. Nat Prod Commun 2015; 10:1207-1209. [PMID: 26411012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023] Open
Abstract
Phytochemical analyses of the bulbs of Eucomis vandermerwei and E. zambesiaca yielded homoisoflavonoids and triterpenoid derivatives. A new (17S*23S*)-epoxy-3β,15β,29-trihydroxy-27-norlanost-8-en-24-one) was isolated from E. zambesiaca. Resnova humifusa yielded homoisoflavonoids, and a tetrahydropyran derivative, 2-methyl-3-(4S*,5R *,7S*-trihydroxy-8S*-hydroxymethyltetrahydro-6H-4-pyranyl)-2-propenoic acid. All compounds were assayed for COX-2 inhibition of cyclooxygenase; 3,5,7-trihydroxy-3-(4'-methoxybenzyl)-4-chromanone was found to have significant activity.
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Sihra JK, Thumser AE, Langat MK, Crouch NR, Mulholland DA. Constituents of Bulbs of three Species of the Hyacinthaceae (Hyacinthoideae): Eucomis vandermerwei, E. zambesiaca and Resnova humifusa. Nat Prod Commun 2015. [DOI: 10.1177/1934578x1501000718] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Phytochemical analyses of the bulbs of Eucomis vandermerwei and E. zambesiaca yielded homoisoflavonoids and triterpenoid derivatives. A new (17 S*,23 S*)-epoxy-3β,15β,29-trihydroxy-27-norlanost-8-en-24-one) was isolated from E. zambesiaca. Resnova humifusa yielded homoisoflavonoids, and a tetrahydropyran derivative, 2-methyl-3-(4 S*,5 R*,7 S*-trihydroxy-8 S*-hydroxymethyltetrahydro-6H-4-pyranyl)-2-propenoic acid. All compounds were assayed for COX-2 inhibition of cyclooxygenase; 3,5,7-trihydroxy-3-(4′-methoxybenzyl)-4-chromanone was found to have significant activity.
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Affiliation(s)
- Jaspreet K. Sihra
- Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey, GU2 7XH, UK
| | - Alfred E. Thumser
- Division of Biochemical Sciences, Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey, GU2 7XH, UK
| | - Moses K. Langat
- Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey, GU2 7XH, UK
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa
| | - Neil R. Crouch
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa
- Ethnobotnany Unit, National Botanical Institute, P.O. Box 52099, Berea Road, Durban, South Africa
| | - Dulcie A. Mulholland
- Department of Chemistry, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey, GU2 7XH, UK
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa
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Ndunda B, Langat MK, Midiwo JO, Omosa LK. Diterpenoid Derivatives of Kenyan Croton sylvaticus. Nat Prod Commun 2015. [DOI: 10.1177/1934578x1501000403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Kenyan Croton sylvaticus Hochst. ex Krauss gave four clerodane diterpenoids, the new ent–3,13 E-clerodadiene-15-formate (1), the known 15-acetoxy- ent-3,13 E-clerodadiene (2), ent-3,13 E-clerodadien-15-ol (3) and hardwickiic acid (4), two known halimane diterpenoids, penduliflaworosin (5) and crotohalimaneic acid (6) and one labdane diterpenoid, labda-13 E-ene-8α,15-diol (7). The compounds, when tested for their anti-microbial activities against Bacillus subtilis, Xanthomonas campestris and Candida albicans, were found to be inactive.
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Affiliation(s)
- Beth Ndunda
- Department of Chemistry, School of Physical Sciences, University of Nairobi, PO Box 30197-00100, Nairobi, Kenya
- Department of Chemistry, FEPS, University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom
| | - Moses K. Langat
- Department of Chemistry, FEPS, University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom
| | - Jacob O. Midiwo
- Department of Chemistry, School of Physical Sciences, University of Nairobi, PO Box 30197-00100, Nairobi, Kenya
| | - Leonidah K. Omosa
- Department of Chemistry, School of Physical Sciences, University of Nairobi, PO Box 30197-00100, Nairobi, Kenya
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Ndunda B, Langat MK, Midiwo JO, Omosa LK. Diterpenoid derivatives of Kenyan Croton sylvaticus. Nat Prod Commun 2015; 10:557-558. [PMID: 25973474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023] Open
Abstract
Kenyan Croton sylvaticus Hochst. ex Krauss gave four clerodane diterpenoids, the new ent-3,13E-clerodadiene-15-formate (1), the known 15-acetoxy-ent-3,13E-clerodadiene (2), ent-3,13E-clerodadien-15-ol (3) and hardwickiic acid (4), two known halimane diterpenoids, penduliflaworosin (5) and crotohalimaneic acid (6) and one labdane diterpenoid, labda-13E-ene-8a,15-diol (7). The compounds, when tested for their anti-microbial activities against Bacillus subtilis, Xanthomonas campestris and Candida albicans, were found to be inactive.
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Tembu VJ, Langat MK, Crouch NR, Mulholland DA. Use of circular dichroism to determine the absolute configuration of a pimarane diterpenoid from the southern African Sclerocroton integerrimus (Euphorbiaceae). Nat Prod Commun 2014; 9:1131-1133. [PMID: 25233590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023] Open
Abstract
From the stem bark and leaves of Sclerocroton integerrimus, eight compounds, including 17-hydroxy-ent-pimara-8(14),15-dien-3-one (1), were isolated. The structures of the compounds were determined on the basis of spectroscopic analysis. The absolute configuration of 17-hydroxy-ent-pimara-8(14),15-dien-3-one was confirmed from electronic circular dichroism studies.
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Tembu VJ, Langat MK, Crouch NR, Mulholland DA. Use of Circular Dichroism to Determine the Absolute Configuration of a Pimarane Diterpenoid from the Southern African Sclerocroton integerrimus (Euphorbiaceae). Nat Prod Commun 2014. [DOI: 10.1177/1934578x1400900818] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
From the stem bark and leaves of Sclerocroton integerrimus, eight compounds, including 17-hydroxy- ent-pimara-8(14),15-dien-3-one (1), were isolated. The structures of the compounds were determined on the basis of spectroscopic analysis. The absolute configuration of 17-hydroxy- ent-pimara-8(14),15-dien-3-one was confirmed from electronic circular dichroism studies.
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Affiliation(s)
- Vuyelwa J. Tembu
- Natural Products Research Group, Department of Chemistry, FEPS, University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa
| | - Moses K. Langat
- Natural Products Research Group, Department of Chemistry, FEPS, University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa
| | - Neil R. Crouch
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa
- Ethnobotany Unit, South African National Biodiversity Institute, PO Box 52099, Berea Road 4007, Durban, South Africa
| | - Dulcie A. Mulholland
- Natural Products Research Group, Department of Chemistry, FEPS, University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom
- School of Chemistry and Physics, University of KwaZulu-Natal, Durban, 4041, South Africa
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Ndunda B, Langat MK, Wanjohi JM, Midiwo JO, Kerubo LO. Alienusolin, a new 4α-deoxyphorbol ester derivative, and crotonimide C, a new glutarimide alkaloid from the Kenyan Croton alienus. Planta Med 2013; 79:1762-1766. [PMID: 24356872 DOI: 10.1055/s-0033-1351044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Two novel compounds, alienusolin, a 4α-deoxyphorbol ester (1), crotonimide C, a glutarimide alkaloid derivative (2), and ten known compounds, julocrotine (3), crotepoxide (4), monodeacetyl crotepoxide (5), dideacetylcrotepoxide, (6), β-senepoxide (7), α-senepoxide (8), (+)-(2S,3R-diacetoxy-1-benzoyloxymethylenecyclohex-4,6-diene (9), benzyl benzoate (10), acetyl aleuritolic (11), and 24-ethylcholesta-4,22-dien-3-one (12) were isolated from the Kenyan Croton alienus. The structures of the compounds were determined using NMR, GCMS, and HRESIMS studies.
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Affiliation(s)
- Beth Ndunda
- Department of Chemistry, Nairobi University, Nairobi, Kenya
| | - Moses K Langat
- Department of Chemistry, FEPS, University of Surrey, Guildford, Surrey, United Kingdom
| | - John M Wanjohi
- Department of Chemistry, Nairobi University, Nairobi, Kenya
| | - Jacob O Midiwo
- Department of Chemistry, Nairobi University, Nairobi, Kenya
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Waller CP, Thumser AE, Langat MK, Crouch NR, Mulholland DA. COX-2 inhibitory activity of homoisoflavanones and xanthones from the bulbs of the Southern African Ledebouria socialis and Ledebouria ovatifolia (Hyacinthaceae: Hyacinthoideae). Phytochemistry 2013; 95:284-290. [PMID: 23859260 DOI: 10.1016/j.phytochem.2013.06.024] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 06/13/2013] [Accepted: 06/17/2013] [Indexed: 06/02/2023]
Abstract
The bulbs of Ledebouria socialis (Hyacinthaceae) yielded the benzocyclobutene homoisoflavonoid, (R)-2',5-dihydroxy-3',4',7-trimethoxyspiro{2H-1-benzopyran-3-(4H)-9-bicyclo[4.2.0]octa[1,3,5]triene}-4-one, socialinone (1). Ledebouria ovatifolia yielded (2ε,3R)-2,5-dihydroxy-7-methoxyspiro[2H-1-benzopyran-3(4H), 5'(6'H)-cyclobuta[f][1,3]benzodioxol]-4-one (2) and the homoisoflavanone, (E)-3-(3',4'-dihydroxybenzylidene)-5,7-dihydroxychroman-4-one, ovatifolionone (5), the dihydrochalcone, 4,4'-dihydroxy-2',6'-dimethoxydihydrochalcone (3), and xanthone, 1,6-dihydroxy-2,3,5-trimethoxy-8-methyl-9H-xanthen-9-one (4) along with 21 known compounds. Structures were determined using spectroscopic techniques. The anti-inflammatory activities of the homoisoflavonoids and xanthones isolated were evaluated against cyclooxygenase-1 and -2 isoenzymes. (R)-3-(3',4'-Dihydroxybenzyl)-7-hydroxy-5-methoxychroman-4-one (7), (E)-3-(3',4'-dihydroxybenzylidene)-7-hydroxy-5-methoxychroman-4-one (10), 1,3,6-trihydroxy-2-methoxy-8-methylxanthen-9-one (6) and ovatifolionone acetate (5Ac) exhibited significant activity against cyclooxygenase-2 at <10μM.
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Affiliation(s)
- Catherine P Waller
- Natural Products Research Group, Department of Chemistry, University of Surrey, Guildford, GU2 7XH Surrey, UK
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Tsamo A, Langat MK, Nkounga P, Kamdem Waffo AF, Nkengfack AE, Mulholland DA. Limonoids from the West African Trichilia welwitschii (Meliaceae). BIOCHEM SYST ECOL 2013. [DOI: 10.1016/j.bse.2013.04.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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