Isolation and characterization of cytotoxic compounds from Anthosperum hispidulum and Eriocephalus tenuifolius.

Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.Cancer is a human tragedy that strikes and kills the lives of our beloved people. With a limited number of effective anticancer drugs from natural resources currently in use, there is a real need for new, safe, cheap and effective anticancer drugs to combat this dreaded and formidable disease. Plants have a long history of use in the treatment of cancer. Several plant-derived anticancer agents including taxol, vinblastine, vincristine, the camptothecin derivatives, topotecan and irinotecan and etoposide derived from epi- podophyllotoxin are in clinical use all over the world. In this study, two endemic plant species from the Rubiaceae and Asteraceae families, namely Anthospermum hispidulum E.Mey. ex Sond. and Eriocephalus tenuifolius DC. were investigated for their anticancer properties. The organic (methanol/dichloromethane, 1:1 v/v) extracts of both plant species were found to have moderate anticancer activity against a panel of three human cancer cell lines namely, breast MCF7, renal TK10 and melanoma UACC62 at the CSIR anticancer screen. Bioassay-guided fractionation of the organic extracts of Anthospermum hispidulum led to the isolation of an active compound which was characterised as ursolic acid. Another compound, namely scopoletin was also isolated. The compounds isolated here are known compounds, but have not previously been reported as present in the genus Anthospermum. Bioassay-guided fractionation of the organic extracts of Eriocephalus tenuifolius resulted in the isolation of 8-O-isobutanoylcumambrin B as the active constituent. This compound is reported to have been isolated from related plant species; however its biological activity is not known. The compounds pectolinagenin, hispidulin, friedelinol and tetracosanoic acid were also isolated, but did not show any significant anticancer activity. The structures of all compounds isolated in this study were elucidated using nuclear magnetic resonance spectroscopy, mass spectroscopy and also by comparison with data reported in the literature

Apollonius and Callimachus on Heracles and Theiodamas: A Metapoetical Interpretation

Apollonius of Rhodes’ digression on Heracles and Theiodamas (Arg. 1.1211-20) alludes to Callimachus’ version of the story in his Aetia (fr. 24-5 Pf.). This article provides a metapoetical interpretation of the intertextual contact. The ways in which both poets deal with Heracles reveal the similar but different reactions of these “Callimachean” poets to the heroic-epic literary tradition

Ethnomedicinal and phytochemical properties of sesquiterpene lactones from Dicoma (Asteraceae) and their anticancer pharmacological activities : a review

Dicoma species belonging to the Asteraceae family are commonly utilized as traditional medicine in Southern Africa. Dicoma anomala, Dicoma capensis, Dicoma schinzii and Dicoma zheyeri are the most common ethnomedicinal plant species used in Southern Africa. The plant species of Dicoma genus are identified as the main source of sesquiterpene lactones. Dicoma species are associated with pharmacological properties such as antiviral, antibacterial, antihelminthic, antispasmodic antiplasmodial, as analgesic, antiinflammatory, , anticancer, , and wound healing properties. The plant species of Dicoma genus are identified as the main source of sesquiterpene lactones. In this review, the authors report the ethnomedicinal and phytochemical properties, and pharmacology of sesquiterpene lactones from the genus Dicoma from 1978 to 2020. There are over eighty (80) reported sesquiterpene lactones isolated from Dicoma species including, germacronolides, eudesmanolides, melampolides, guaianolides and pseudoguaianolides. Sesquiterpene lactones possess antimalarial, anticancer and antiinflammation activities due to their structural diversity. The diagnostic search on phytochemistry of sesquiterpene lactones from Dicoma carried out in the 70’s has limited pharmacological screening activities; hence these may need to be revisited and explored. Furthermore, the literature search conducted in this review showed that out of the 35 Dicoma species, seven species were investigated, and their medicinal uses, pharmacology and photochemistry reported. The recommendation drawn is that Dicoma species that are not investigated and not fully exploited should be studied for their phytochemicals and efficacy. The information compiled in this review on the pharmacological, phytochemistry and ethnomedicinal activities of genus Dicoma was obtained from relevant literature sources, including books, book chapters, websites, theses, reviews and research articles from databases such as Web of Science, Scopus, Science Direct, BioMed Central, Springer link, PubMed, and Google Scholar.The South African National Research foundation (NRF)http://www.elsevier.com/locate/sciafhj2022Chemistr

Additional file 4: of Anti-aging potential of extracts from Sclerocarya birrea (A. Rich.) Hochst and its chemical profiling by UPLC-Q-TOF-MS

Negative mode BPI chromatogram of quinic acid pure standard overlaid with that of Marula stem ethanol extract. A comparison of the retention time of quinic acid pure standard with that of peak 1 identified a quinic acid in Marula stem ethanol extract. (PPTX 85 kb

Additional file 11: of Anti-aging potential of extracts from Sclerocarya birrea (A. Rich.) Hochst and its chemical profiling by UPLC-Q-TOF-MS

MS/MS fragmentation pattern of epicatechin gallate pure standard overlaid with MS/MS fragmentation of peak 7. A comparison of the MS/MS fragmentation pattern of epicatechin gallate pure standard to that of peak 7 identified as epicatechin gallate in Marula stem ethanol extract. (PPTX 84 kb

<i>Ent</i>-abietane diterpenoids from <i>Suregada zanzibariensis</i> Baill. (Euphorbiaceae), their cytotoxic and anticancer properties

<p>The stem bark extract of <i>Suregada zanzibariensis</i> afforded a previously undescribed <i>ent</i>-abietane diterpenoid trivially named mangiolide (<b>1</b>) and a known jolkinolide B (<b>2</b>) via anticancer bioassay-guided fractionation. The CH₂Cl₂:MeOH extract of <i>S. zanzibariensis</i> 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 <b>1</b>, 6α-acetoxy-14-keto-<i>ent</i>-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 <b>2</b>, 8,13-diepoxy-13,15-<i>ent</i>-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).</p

Structure-Activity Relationship Study of Sesquiterpene Lactones and Their Semi-Synthetic Amino Derivatives as Potential Antitrypanosomal Products

Sesquiterpene lactones (STLs) are natural products that have potent antitrypanosomal activity in vitro and, in the case of cynaropicrin, also reduce parasitemia in the murine model of trypanosomiasis. To explore their structure-antitrypanosomal activity relationships, a set of 34 natural and semi-synthetic STLs and amino-STLs was tested in vitro against T. b. rhodesiense (which causes East African sleeping sickness) and mammalian cancer cells (rat bone myoblast L6 cells). It was found that the α-methylene-γ-lactone moiety is necessary for both antitrypanosomal effects and cytotoxicity. Antitrypanosomal selectivity is facilitated by 2-(hydroxymethyl)acrylate or 3,4-dihydroxy-2-methylenebutylate side chains, and by the presence of cyclopentenone rings. Semi-synthetic STL amines with morpholino and dimethylamino groups showed improved in vitro activity over the native STLs. The dimethylamino derivative of cynaropicrin was prepared and tested orally in the T. b. rhodesiense acute mouse model, where it showed reduced toxicity over cynaropicrin, but also lost antitrypanosomal activity

Protective Roles of Monsonia angustifolia and Its Active Compounds in Experimental Models of Alzheimer’s Disease

Alzheimer’s disease (AD), a progressive neurodegenerative disorder, is characterized by the accumulation of neurotoxic β-amyloid (Aβ) peptides, which consequently affects cognitive decline and memory impairment. Current research on AD treatment is actively focusing on the prevention of neurotoxic Aβ peptide accumulation. Monsonia angustifolia is reported to be consumed as an indigenous vegetable in Tanzania. In this study, we investigated the effect of the ethanol (EtOH) extract of M. angustifolia dried ground material on Aβ production and spatial learning ability as protection against AD. The formation of Aβ peptides was significantly reduced in HeLa cells stably transfected with the Swedish mutant form of β-amyloid precursor protein (APPsw) after treatment with a 60% EtOH extract of M. angustifolia. We next examined the cognitive-improving effects of the EtOH extract in vivo. Tg2576 mice were treated with extract for 6 months and subjected to Morris water maze and novel object recognition tests. The results showed that the 60% EtOH extract of M. angustifolia significantly ameliorated behavioral deficits of the AD transgenic mice and reduced the level of insoluble Aβ42 in the cerebral cortex and hippocampus. We further found that the 60% EtOH extract was effective for memory function recovery after shorter treatment (4 months). In addition, we isolated and identified several single compounds, justicidin A, 5-methoxyjusticidin A, chinensinaphthol, retrochinensinaphthol methyl ether, and suchilactone, from M. angustifolia and tested these compounds. Among them, justicidin A potently decreased the formation of Aβ in APPsw-transfected cells. These data suggest that the 60% EtOH extract of M. angustifolia has the potential to be developed as a treatment of AD. Furthermore, justicidin A may contribute, at least partially, to the Aβ alteration observed with the extract treatment