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Dulcie A. Mulholland - One of the best experts on this subject based on the ideXlab platform.
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Antiproliferative Bufadienolides from the Bulbs of Drimia altissima.
Journal of natural products, 2021Co-Authors: Linda C. Langat, Moses K. Langat, Wolfgang Wetschnig, Walter Knirsch, Dulcie A. MulhollandAbstract: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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Phytochemical Investigations of Three Rhodocodon (Hyacinthaceae Sensu APG II) Species
2017Co-Authors: Sianne Schwikkard, Moses K. Langat, Wolfgang Wetschnig, Walter Knirsch, Jl Andriantiana, Alaa Alqahtani, Andrius Jaksevicius, Elizabeth I. Opara, Dulcie A. MulhollandAbstract: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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the chemistry and biological activity of the Hyacinthaceae
Natural Product Reports, 2013Co-Authors: Sianne Schwikkard, Dulcie A. Mulholland, Neil R. CrouchAbstract:Covering: 1914 to 2012 The Hyacinthaceae (sensu APGII), with approximately 900 species in about 70 genera, can be divided into three main subfamilies, the Hyacinthoideae, the Urgineoideae and the Ornithogaloideae, with a small fourth subfamily the Oziroeoideae, restricted to South America. The plants included in this family have long been used in traditional medicine for a wide range of medicinal applications. This, together with some significant toxicity to livestock has led to the chemical composition of many of the species being investigated. The compounds found are, for the most part, subfamily-restricted, with homoisoflavanones and spirocyclic nortriterpenoids characterising the Hyacinthoideae, bufadienolides characterising the Urgineoideae, and cardenolides and steroidal glycosides characterising the Ornithogaloideae. The phytochemical profiles of 38 genera of the Hyacinthaceae will be discussed as well as any biological activity associated with both crude extracts and compounds isolated. The Hyacinthaceae of southern Africa were last reviewed in 2000 (T. S. Pohl, N. R. Crouch and D. A. Mulholland, Curr. Org. Chem., 2000, 4, 1287–1324; ref. 1); the current contribution considers the family at a global level.
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homoisoflavanones from pseudoprospero firmifolium of the monotypic tribe pseudoprospereae Hyacinthaceae hyacinthoideae
Phytochemistry, 2007Co-Authors: Chantal Koorbanally, Neil R. Crouch, Dulcie A. Mulholland, Sarisha Sewjee, Anthony P DoldAbstract:Five 3-hydroxy-type homoisoflavonoids, 3,5-dihydroxy-7,8-dimethoxy-3-(3',4'-dimethoxybenzyl)-4-chromanone, 3,5-dihydroxy-7-methoxy-3-(3',4'-dimethoxybenzyl)-4-chromanone, 3,5-dihydroxy-7,8-dimethoxy-3-(3'-hydroxy-4'-methoxybenzyl)-4-chromanone, 3,5,6-trihydroxy-7-methoxy-3-(3'-hydroxy-4'-methoxybenzyl)-4-chromanone and 3,5,7-trihydroxy-3-(3'-hydroxy-4'methoxybenzyl)-4-chromanone in addition to the nortriterpenoid, 15-deoxoeucosterol, have been isolated from the dichloromethane extract of the bulbs of Pseudoprospero firmifolium, the sole representative of the tribe Pseudoprospereae of the subfamily Hyacinthoideae of the Hyacinthaceae.
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Bufadienolides from Drimia macrocentra and Urginea riparia (Hyacinthaceae: Urgineoideae)
Phytochemistry, 2007Co-Authors: Nivan Moodley, Neil R. Crouch, Dulcie A. MulhollandAbstract:The bufadienolides, rubellin and riparianin were isolated from the bulbs of Drimia macrocentra and Urginea riparia (Hyacinthaceae) respectively. Rubellin and riparianin contain a carbohydrate moiety doubly linked to the bufadienolide aglycone at the C-2 and C-3 positions. Riparianin showed moderate activity when tested against MCF7 (breast), TK10 (renal) and UACC62 (melanoma) cell lines.
Neil R. Crouch - One of the best experts on this subject based on the ideXlab platform.
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the chemistry and biological activity of the Hyacinthaceae
Natural Product Reports, 2013Co-Authors: Sianne Schwikkard, Dulcie A. Mulholland, Neil R. CrouchAbstract:Covering: 1914 to 2012 The Hyacinthaceae (sensu APGII), with approximately 900 species in about 70 genera, can be divided into three main subfamilies, the Hyacinthoideae, the Urgineoideae and the Ornithogaloideae, with a small fourth subfamily the Oziroeoideae, restricted to South America. The plants included in this family have long been used in traditional medicine for a wide range of medicinal applications. This, together with some significant toxicity to livestock has led to the chemical composition of many of the species being investigated. The compounds found are, for the most part, subfamily-restricted, with homoisoflavanones and spirocyclic nortriterpenoids characterising the Hyacinthoideae, bufadienolides characterising the Urgineoideae, and cardenolides and steroidal glycosides characterising the Ornithogaloideae. The phytochemical profiles of 38 genera of the Hyacinthaceae will be discussed as well as any biological activity associated with both crude extracts and compounds isolated. The Hyacinthaceae of southern Africa were last reviewed in 2000 (T. S. Pohl, N. R. Crouch and D. A. Mulholland, Curr. Org. Chem., 2000, 4, 1287–1324; ref. 1); the current contribution considers the family at a global level.
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homoisoflavanones from pseudoprospero firmifolium of the monotypic tribe pseudoprospereae Hyacinthaceae hyacinthoideae
Phytochemistry, 2007Co-Authors: Chantal Koorbanally, Neil R. Crouch, Dulcie A. Mulholland, Sarisha Sewjee, Anthony P DoldAbstract:Five 3-hydroxy-type homoisoflavonoids, 3,5-dihydroxy-7,8-dimethoxy-3-(3',4'-dimethoxybenzyl)-4-chromanone, 3,5-dihydroxy-7-methoxy-3-(3',4'-dimethoxybenzyl)-4-chromanone, 3,5-dihydroxy-7,8-dimethoxy-3-(3'-hydroxy-4'-methoxybenzyl)-4-chromanone, 3,5,6-trihydroxy-7-methoxy-3-(3'-hydroxy-4'-methoxybenzyl)-4-chromanone and 3,5,7-trihydroxy-3-(3'-hydroxy-4'methoxybenzyl)-4-chromanone in addition to the nortriterpenoid, 15-deoxoeucosterol, have been isolated from the dichloromethane extract of the bulbs of Pseudoprospero firmifolium, the sole representative of the tribe Pseudoprospereae of the subfamily Hyacinthoideae of the Hyacinthaceae.
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Bufadienolides from Drimia macrocentra and Urginea riparia (Hyacinthaceae: Urgineoideae)
Phytochemistry, 2007Co-Authors: Nivan Moodley, Neil R. Crouch, Dulcie A. MulhollandAbstract:The bufadienolides, rubellin and riparianin were isolated from the bulbs of Drimia macrocentra and Urginea riparia (Hyacinthaceae) respectively. Rubellin and riparianin contain a carbohydrate moiety doubly linked to the bufadienolide aglycone at the C-2 and C-3 positions. Riparianin showed moderate activity when tested against MCF7 (breast), TK10 (renal) and UACC62 (melanoma) cell lines.
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bufadienolides from the southern african drimia depressa Hyacinthaceae urgineoideae
Phytochemistry, 2007Co-Authors: Neil R. Crouch, Dulcie A. Mulholland, A LangloisAbstract:Two bufadienolides, 3beta,16beta-dihydroxy-5beta-bufa-20,22-dienolide and 16beta-hydroxy-5beta-bufa-20,22-dienolide-3beta-O-beta-d-galactoside, have been isolated from bulbs of the poisonous South African geophyte Drimia depressa (Hyacinthaceae).
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3 benzyl 4 chromanones homoisoflavanones from bulbs of the ethnomedicinal geophyte ledebouria revoluta Hyacinthaceae
South African Journal of Botany, 2006Co-Authors: Nivan Moodley, Neil R. Crouch, Dulcie A. Mulholland, Desmond Slade, Daneel FerreiraAbstract:Abstract Ledebouria revoluta (Hyacinthaceae: Hyacinthoideae), used widely as an ethnomedicinal in southern Africa, has been characterised phytochemically for the first time. Four homoisoflavanones (3-benzyl-4-chromanones) were isolated from the bulbs and their absolute configuration at C-3 determined using CD spectroscopy. The chemotaxonomic and ethnopharmacological significance of the presence of 3-benzyl-4-chromanones is discussed.
Sianne Schwikkard - One of the best experts on this subject based on the ideXlab platform.
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the antiangiogenic activity of naturally occurring and synthetic homoisoflavonoids from the Hyacinthaceae sensu apgii
PMC, 2019Co-Authors: Sianne Schwikkard, Alaa Alqahtani, Hannah Whitmore, Kamakshi Sishtla, Rania S Sulaiman, Trupti Shetty, Halesha D Basavarajappa, Catherine Waller, Lennart FrankemoelleAbstract: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, ...
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The Antiangiogenic Activity of Naturally Occurring and Synthetic Homoisoflavonoids from the Hyacinthaceae (sensu APGII)
2019Co-Authors: Sianne Schwikkard, Alaa Alqahtani, Hannah Whitmore, Kamakshi Sishtla, Rania S Sulaiman, Trupti Shetty, Halesha D Basavarajappa, Catherine Waller, Lennart Frankemoelle, Andy ChapmanAbstract: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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Phytochemical Investigations of Three Rhodocodon (Hyacinthaceae Sensu APG II) Species
2017Co-Authors: Sianne Schwikkard, Moses K. Langat, Wolfgang Wetschnig, Walter Knirsch, Jl Andriantiana, Alaa Alqahtani, Andrius Jaksevicius, Elizabeth I. Opara, Dulcie A. MulhollandAbstract: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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the chemistry and biological activity of the Hyacinthaceae
Natural Product Reports, 2013Co-Authors: Sianne Schwikkard, Dulcie A. Mulholland, Neil R. CrouchAbstract:Covering: 1914 to 2012 The Hyacinthaceae (sensu APGII), with approximately 900 species in about 70 genera, can be divided into three main subfamilies, the Hyacinthoideae, the Urgineoideae and the Ornithogaloideae, with a small fourth subfamily the Oziroeoideae, restricted to South America. The plants included in this family have long been used in traditional medicine for a wide range of medicinal applications. This, together with some significant toxicity to livestock has led to the chemical composition of many of the species being investigated. The compounds found are, for the most part, subfamily-restricted, with homoisoflavanones and spirocyclic nortriterpenoids characterising the Hyacinthoideae, bufadienolides characterising the Urgineoideae, and cardenolides and steroidal glycosides characterising the Ornithogaloideae. The phytochemical profiles of 38 genera of the Hyacinthaceae will be discussed as well as any biological activity associated with both crude extracts and compounds isolated. The Hyacinthaceae of southern Africa were last reviewed in 2000 (T. S. Pohl, N. R. Crouch and D. A. Mulholland, Curr. Org. Chem., 2000, 4, 1287–1324; ref. 1); the current contribution considers the family at a global level.
Wolfgang Wetschnig - One of the best experts on this subject based on the ideXlab platform.
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Antiproliferative Bufadienolides from the Bulbs of Drimia altissima.
Journal of natural products, 2021Co-Authors: Linda C. Langat, Moses K. Langat, Wolfgang Wetschnig, Walter Knirsch, Dulcie A. MulhollandAbstract: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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Phytochemical Investigations of Three Rhodocodon (Hyacinthaceae Sensu APG II) Species
2017Co-Authors: Sianne Schwikkard, Moses K. Langat, Wolfgang Wetschnig, Walter Knirsch, Jl Andriantiana, Alaa Alqahtani, Andrius Jaksevicius, Elizabeth I. Opara, Dulcie A. MulhollandAbstract: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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the scilla plumbea puzzle present status of the genus scilla sensu lato in southern africa and description of spetaea lachenaliiflora a new genus and species of massonieae Hyacinthaceae
Taxon, 2003Co-Authors: Wolfgang Wetschnig, Martin PfosserAbstract:We have studied a taxon from South Africa that has been hidden for more than 150 years within Scilla plumbea (Hyacinthaceae). However, phylogenetic reconstruction based on trnL-F data, morphological evidence (including seed characters), and karyology suggest independent status. DNA data place it close to the Daubenya alliance but not close to any particular genus of Massonieae previously included within Scilla s.l. Unique characters of seeds indicate that this taxon does not belong to the Daubenyaclade. Analysis of the iconotype of Scilla plumbea Lindl., on the other hand, reveals morphological details suggesting membership in the Scilla natalensis clade (= genus Merwillain the recent classification of Speta). Merwilla, however, occupies a basal position among Massonieae and is not related to the Daubenyaclade. Based on all data, we describe this taxon as a new genus and species Spetaea lacheneliifloraWetschnig & Pfosser.
Mustafa Kucukoduk - One of the best experts on this subject based on the ideXlab platform.
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muscari turcicum liliaceae Hyacinthaceae a new species from south anatolia turkey
Botanical Journal of the Linnean Society, 2007Co-Authors: Tuna Uysal, Huseyin Dural, Kuddisi Ertuğrul, Mustafa KucukodukAbstract:Muscari turcicum Uysal, Ertugrul & Dural (Liliaceae/Hyacinthaceae) is described and illustrated from south Anatolia, Turkey. This species grows on alpine steppe in the Middle Taurus (C4 Konya Province). Muscari turcicum, an endemic confined to the Middle Taurus, is closely related to M. discolor Boiss. & Hausskn. and M. anatolicum Cowley & Ozhatay. Diagnostic morphological characters are discussed and compared with those of closely related taxa. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 154, 233–236.
