Saponin with antibacterial activity from the roots of Albizia adianthifolia

AbstractAn unprecedented saponin is being reported herein together with five known compounds from the methanol extract of the roots of Albizia adianthifolia. The metabolites were obtained over repe...

Cytotoxicity of the bisphenolic honokiol from Magnolia officinalis against multiple drug-resistant tumor cells as determined by pharmacogenomics and molecular docking.

A main problem in oncology is the development of drug-resistance. Some plant-derived lignans are established in cancer therapy, e.g. the semisynthetic epipodophyllotoxins etoposide and teniposide. Their activity is, unfortunately, hampered by the ATP-binding cassette (ABC) efflux transporter, P-glycoprotein. Here, we investigated the bisphenolic honokiol derived from Magnolia officinalis. P-glycoprotein-overexpressing CEM/ADR5000 cells were not cross-resistant to honokiol, but MDA-MB-231 BRCP cells transfected with another ABC-transporter, BCRP, revealed 3-fold resistance. Further drug resistance mechanisms analyzed study was the tumor suppressor TP53 and the epidermal growth factor recepto…

Furoquinolines and dihydrooxazole alkaloids with cytotoxic activity from the stem bark of Araliopsis soyauxii.

Abstract Two new furoquinoline alkaloids, maculine B (1) and kokusaginine B (2) and one new dihydrooxazole alkaloid, veprisazole (3), along with four known compounds namely, N13-methyl-3-methoxyrutaecarpine (4), flindersiamine (5), skimmianine (6) and tilianin (7) were isolated from the methanol extract of the stem bark of Araliopsis soyauxii Engl. by various chromatographic methods. Their structures were determined using spectrometry and spectroscopic techniques including NMR and MS. The cytotoxicity of the new compounds compared to that of doxorubicin, the reference anticancer compound, was determined on a panel of nine cancer cell lines including sensitive and drug resistant phenotypes. …

Bioactivity of fractions and constituents of Piper capense fruits towards a broad panel of cancer cells.

Abstract Ethnopharmacological relevance Piper capense is a medicinal spice whose fruits are traditionally used as aqueous decoction to heal several ailments such as trypanosomiasis, helminthic infections, and cancer. Aim of the study. (1) To perform phytochemical investigation of the methanol extract of Piper capense; (2) to evaluate the cytotoxicity of botanicals (PCF, fractions PCFa-e), isolated phytochemicals on a broad panel of animal and human cancer cell lines; (3) to evaluate the induction of apoptosis of the most active samples. Material and methods Resazurin reduction assay (RRA) was used to determine the cytotoxicity of the studied samples. Cell cycle distribution (PI staining), a…

Anticancer activities of six selected natural compounds of some Cameroonian medicinal plants.

BACKGROUND: Natural products are well recognized as sources of drugs in several human ailments. In the present work, we carried out a preliminary screening of six natural compounds, xanthone V(1) (1); 2-acetylfuro-1,4-naphthoquinone (2); physcion (3); bisvismiaquinone (4); vismiaquinone (5); 1,8-dihydroxy-3-geranyloxy-6-methylanthraquinone (6) against MiaPaCa-2 pancreatic and CCRF-CEM leukemia cells and their multidrug-resistant subline, CEM/ADR5000. Compounds 1 and 2 were then tested in several other cancer cells and their possible mode of action were investigated. METHODOLOGY/FINDINGS: The tested compounds were previously isolated from the Cameroonian medicinal plants Vismia laurentii (1,…

Unprecedented new nonadecylpara-hydroperoxycinnamate isolated fromErythrina excelsaand its cytotoxic activity

A new unprecedented cinnamate derivative (1) was obtained from Erythrina excelsa (Leguminosae) and identified as nonadecyl para-hydroperoxycinnamate. This compound was isolated together with three known compounds, namely lupeol (2), mixture of sitosterol and stigmasterol (3), and isoneorautenol (4). Their structures were established on the basis of NMR and mass spectroscopic data in conjunction with those reported in the literature. Compound 1 was evaluated for its capability of inhibiting cancer cell lines and growth of a panel of microbial strains. It turned out that 1 is moderately to significantly cytotoxic against six cancer cell lines and shows weak to no antimicrobial activity.

Coumarins and Related Compounds from the Medicinal Plants of Africa

Coumarins (1-benzopyran-2-one) are chemical compounds in the benzopyrone class of organic compounds found in many plants. Coumarins possess a variety of biological properties, including antimicrobial, antiviral, antiinflammatory, antidiabetic, antioxidant, and enzyme inhibitory activity. This chapter gives an overview of the isolation, structural features, and pharmacological actions of variety of coumarins produced by the African plants. The biosynthetic pathway of coumarins is also discussed in this chapter. We identify 117 coumarins in African plants, of which 48 are new. The pharmacological activities of 54 of these coumarins are reported and documented in this chapter.

Cytotoxicity of compounds from Xylopia aethiopica towards multi-factorial drug-resistant cancer cells.

Abstract Introduction Multidrug resistance (MDR) in cancer represent a major hurdle in chemotherapy. Previously, the methanol extract of the medicinal spice Xylopia aethiopica displayed considerable cytotoxicity against multidrug resistant (MDR) cancer cell lines. Methods The present study was designed to assess the cytotoxicity of compounds, 16 α -hydroxy- ent -kauran-19-oic acid ( 2 ), 3,4′,5-trihydroxy-6″,6″-dimethylpyrano[2,3-g]flavone ( 3 ), isotetrandrine ( 5 ) and trans -tiliroside ( 6 ) derived from the methanol crude extract of Xylopia aethiopica against 9 drug-sensitive and -resistant cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of these c…

Cytotoxicity of seven naturally occurring phenolic compounds towards multi-factorial drug-resistant cancer cells

Abstract Introduction In medical oncology, multi-drug resistance (MDR) of cancer cells continues to be a major impediment. We are in quest of novel anti-proliferative agents to overcome drug-resistant tumor cells. Methods In the present study, we investigated the cytotoxicity of 7 naturally occurring phenolic compounds including two isoflavonoids alpinumisoflavone ( 1 ) and laburnetin ( 2 ), one biflavonoid amentoflavone ( 3) , three lignans pycnanthulignene A ( 4 ), pycnanthulignene B ( 5 ), and syringaresinol ( 7 ) and one xanthone, euxanthone ( 6 ) against 9 drug-sensitive and MDR cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of these compounds, w…

Polyacanthoside A, a new oleanane-type triterpenoid saponin with cytotoxic effects from the leaves of Acacia polyacantha (Fabaceae)

The chemical investigation of the leaves and stem bark of Acacia polyacantha (Fabaceae) led to the isolation of a new oleanane-type triterpenoid saponin named polyacanthoside A 1 together with fifteen known compounds. Their structures were established from spectral , mainly HRESIMS, 1D NMR and 2D NMR and by comparison with literature data. The cytotoxicity of compound 1 and the analogues 8 as well as doxorubicin was determined in a panel of 9 cancer cell lines including sensitive and drug resistant phenotypes. Unlike the analogue 8, compound 1 as well as doxorubicin displayed cytotoxic effects in all the 9 tested cancer cell lines with IC50 values ranged from 8.90 μM (towards CCRF-CEM leuke…

Synthesis and Cytotoxicity of 1,4-Dihydropyridines and an Unexpected 1,3-Oxazin-6-one

Eight heterocycles have been prepared in a one-pot reaction manner based on the Hantzsch dihydropyridine synthesis. The synthesis afforded seven dihydropyridines (DHP) and one unexpected 1,3-oxazin-6-one. Their structures were confirmed based on NMR spectroscopy and mass spectrometry. The obtained products have been evaluated for their cytotoxicity against eight cancer cell lines and one normal cell line. Two halogenated DHPs (7 and 8) displayed cytotoxicity toward all the nine tested cancer cell lines with IC50 values from 4.10 to 58.90 μm, while others showed selective activities. DHPs (7 and 8) bearing a Me group at C(2) and C(6) as well as a halogenated substituent at C(4′) were more an…

Cytotoxic flavonoids from two Lonchocarpus species

A new isoflavone, 4′-prenyloxyvigvexin A (1) and a new pterocarpan, (6aR,11aR)-3,8-dimethoxybitucarpin B (2) were isolated from the leaves of Lonchocarpus bussei and the stem bark of Lonchocarpus eriocalyx, respectively. The extract of L. bussei also gave four known isoflavones, maximaisoflavone H, 7,2′-dimethoxy-3′,4′-methylenedioxyisoflavone, 6,7,3′-trimethoxy-4′,5′-methylenedioxyisoflavone, durmillone; a chalcone, 4-hydroxylonchocarpin; a geranylated phenylpropanol, colenemol; and two known pterocarpans, (6aR,11aR)-maackiain and (6aR,11aR)-edunol. (6aR,11aR)-Edunol was also isolated from the stem bark of L. eriocalyx. The structures of the isolated compounds were elucidated by spectrosco…

Caffeate and piperidine-3-ol derivatives from the stem bark of Cassia sieberiana

A new caffeate derivative from the ethanol extract of the stem bark of Cassia sieberiana DC. is described herein along with the known secondary metabolites spectaline (2), iso-6-cassine (3), 3-O-methyl-chiro-inositol (4), monobehenin (5), octyl nonadecyloate (6), β-sitosterol (7), stigmasterol (8) and sitosterol 3-O-β-D-glucopyranoside (9). The chemical structures were elucidated by means of various spectroscopic and spectrometric techniques. Extract and isolated compounds were devoid of inhibitory action against the herein selected bacterial strains (MICs > 256 μg/mL) but showed capacities to reduce 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical (EC50 50 6.47 ± 0.48 μg/mL).

Cytotoxicity and Modes of Action of the Methanol Extracts of Six Cameroonian Medicinal Plants against Multidrug-Resistant Tumor Cells

Introduction. The present study aims at evaluating the cytotoxicity of twelve parts from six Cameroonian medicinal plants on sensitive and drug-resistant cancer cell lines. We also studied the mode of action of the most active plants, Gladiolus quartinianus, Vepris soyauxii, and Anonidium mannii. Methods. The cytotoxicity of the extracts was determined using a resazurin assay. Flow cytometry was used for cell-cycle analysis and detection of apoptosis, analysis of mitochondrial membrane potential (MMP), and measurement of reactive oxygen species (ROS). Results. At 40 g/mL, three extracts showed a growth of CCRF-CEM leukemia cells by less than 50%. This includes the extracts from G. quartinia…

Pharmacogenomics of Cameroonian traditional herbal medicine for cancer therapy

Abstract Ethnopharmacological relevance A socio-economic burden associated with cancers is reported in Africa. Ethnopharmacological usages such as immune and skin disorders, inflammatory, and others chould be considered when selecting plants used to treat cancer, since these reflect disease states bearing relevance to cancer or a cancer symptoms. Materials and methods Documented compounds of Cameroonian medicinal plants were used as keywords in the National Cancer Institute (NCI) database to establish a library of cytotoxic compounds. Cellular and pharmacogenomic profiling was then performed for the 10 most cytotoxic natural products. By COMPARE and hierarchical cluster analyses, candidate …

Cytotoxicity of the crude extract and constituents of the bark of Fagara tessmannii towards multi-factorial drug resistant cancer cells.

Abstract Ethnopharmacological relevance Fagara tessmannii Engl. is an African medicinal plant used in Cameroonian traditional medicine to treat various types of cancers. Aim of the study This work was designed to determine the cytotoxicity of the crude extract (FTB), fractions (FTBa-d) and compounds isolated from the bark of Fagara tessmannii, namely lupeol (1), fagaramide (2), zanthoxyline (3), hesperidin (4), nitidine chloride (5), fagaridine chloride (6), and β-sitosterol-3-O-β-D-glucopyranoside (7). The study was extended to the mode of induction of apoptosis by FTB, compounds 5 and 6. Materials and methods The resazurin reduction assay was used to evaluate the cytotoxicity of samples. …

Unprecedented new nonadecyl para-hydroperoxycinnamate isolated from Erythrina excelsa and its cytotoxic activity

A new unprecedented cinnamate derivative (1) was obtained from Erythrina excelsa (Leguminosae) and identified as nonadecyl para-hydroperoxycinnamate. This compound was isolated together with three known compounds, namely lupeol (2), mixture of sitosterol and stigmasterol (3), and isoneorautenol (4). Their structures were established on the basis of NMR and mass spectroscopic data in conjunction with those reported in the literature. Compound 1 was evaluated for its capability of inhibiting cancer cell lines and growth of a panel of microbial strains. It turned out that 1 is moderately to significantly cytotoxic against six cancer cell lines and shows weak to no antimicrobial activity.

Cytotoxicity of three naturally occurring flavonoid derived compounds (artocarpesin, cycloartocarpesin and isobavachalcone) towards multi-factorial drug-resistant cancer cells.

Abstract Introduction Cancer remains an aggressive deadly disease, if drug resistance develops. This problem is aggravated by the fact that multiple rather than single mechanisms are involved in resistance and that multidrug resistance (MDR) phenomena cause inefficacy of many clinical established anticancer drugs. We are seeking for novel cytotoxic phytochemicals to combat drug-resistant tumour cells. Methods In the present study, we investigated the cytotoxicity of three naturally occurring flavonoids including two flavones artocarpesin (1) and cycloartocarpesin (2) and one chalcone, isobavachalcone (3) against 9 drug-sensitive and MDR cancer cell lines. The resazurin reduction assay was u…

Cytotoxicity and modes of action of four naturally occuring benzophenones: 2,2′,5,6′-Tetrahydroxybenzophenone, guttiferone E, isogarcinol and isoxanthochymol

Abstract Introduction The emergence of drug-resistant cancer cells drastically reduces the efficacy of many antineoplasic agents and, consequently, increases the frequency of therapeutic failure. Benzophenones are known to display many pharmacological properties including cytotoxic activities. The present study was aimed at investigating the cytotoxicity and the modes of action of four naturally occurring benzophenones 2,2′,5,6′-tetrahydroxybenzophenone ( 1 ), isogarcinol ( 2 ), isoxanthochymol ( 3 ) and guttiferone E ( 4 ) on a panel of eleven cancer cell lines including various sensitive and drug-resistant phenotypes. Methods The cytotoxicity of the compounds was determined using a resazu…

Cytotoxicity and modes of action of four Cameroonian dietary spices ethno-medically used to treat cancers: Echinops giganteus, Xylopia aethiopica, Imperata cylindrica and Piper capense.

Abstract Ethnopharmacological relevance. Echinops giganteus , Imperata cylindrica , Piper capense and Xylopia aethiopica are four medicinal spices used in Cameroon to treat cancers. Aim of the study The above plants previously displayed cytotoxicty against leukemia CCRF-CEM and CEM/ADR5000 cell lines as well as human pancreatic MiaPaCa-2 cells. The present study aims at emphasizing the study of the cytotoxicity and the modes of action of the above plants on a panel of ten cancer cell lines including various sensitive and drug-resistant phenotypes. The study has been extended to the isolation of the bioactive constituents from Echinops giganteus . Materials and methods The cytotoxicity of th…

Harmful and Protective Effects of Phenolic Compounds from African Medicinal Plants

Phenolic phytochemicals include flavonoids, phenolic acids, tannins, lignans, coumarins, quinones, xanthones, cucurmin, and several other plant compounds owing hydroxyl group bonded directly to an aromatic hydrocarbon group. In plants, they play a variety of protective effects against abiotic stresses like UV light or biotic stresses such as predator and pathogen attacks. This role is exploited by humans to treat several ailments including bacterial, fungal, protozoal and viral infections, inflammation, cancer, and diabetes. Numbers of them are known to display direct protection on cells or organs in humans and animals. In contrast, some of others rather have harmful or toxic effects. In th…

Cytotoxicity of a naturally occurring furoquinoline alkaloid and four acridone alkaloids towards multi-factorial drug-resistant cancer cells

Abstract Introduction Chemotherapy is one of the preferred mode of treatment of malignancies, but is complicated by the expression of diverse resistance mechanisms of cancer cells. Methods In the present study, we investigated the cytotoxicity of five alkaloids including a furoquinoline montrofoline (1) and four acridones namely 1-hydroxy-4-methoxy-10-methylacridone (2), norevoxanthine (3), evoxanthine (4), 1,3-dimethoxy-10-methylacridone (5) against 9 drug-sensitive and multidrug-resistant (MDR) cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of these compounds, whilst caspase-Glo assay was used to detect caspase activation. Cell cycle, mitochondrial …

Antiproliferative Potential of African Medicinal Plants

Increasingly, cancer is recognized as a critical public health problem in Africa. Medicinal plants constitute a good alternative treatment, considering the rich biodiversity of the continent. Scientific evidence of the antiproliferative activity of African medicinal plants is more and more common. The most prominent results reported include the cytotoxic effects of plants of the families Moraceae, Guttiferae, Fabaceae, as well as compounds of the groups of terpenoids and phenolics derived from African plants.

Donellanic acids A–C: new cyclopropanic oleanane derivatives from Donella ubanguiensis (Sapotaceae)

Abstract Three new cyclopropanic oleanane triterpenoids and ten known compounds were obtained from Donella ubanguiensis using chromatographic methods. The structures were established on the basis of mass spectrometric and NMR data and by comparison with values reported in the literature. The structures of the new compounds were confirmed by X-ray crystallography. A part of the isolated compounds was evaluated for cytotoxic and antimicrobial activities.

Cytotoxicity of 18 Cameroonian medicinal plants against drug sensitive and multi-factorial drug resistant cancer cells

Abstract Ethnopharmacological relevance Cameroonian medicinal plants are traditionally used to treat many ailments, including cancer and related diseases. Cancer is characterized as a condition with complex signs and symptoms. It has been recommended that ethnopharmacological usages such as immune and skin disorders, inflammatory, infectious, parasitic and viral diseases should be taken into account when selecting plants for anticancer screenings, since these reflect disease states bearing relevance to cancer or cancer-like symptoms. Aim of the study The present study aims at investigating 20 methanol extracts from 15 Cameroonian medicinal plants on a panel of human cancer cell lines, inclu…

Caffeate and piperidine-3-ol derivatives from the stem bark of Cassia sieberiana

A new caffeate derivative from the ethanol extract of the stem bark of Cassia sieberiana DC. is described herein along with the known secondary metabolites spectaline (2), iso-6-cassine (3), 3-O-methyl-chiro-inositol (4), monobehenin (5), octyl nonadecyloate (6), β-sitosterol (7), stigmasterol (8) and sitosterol 3-O-β-D-glucopyranoside (9). The chemical structures were elucidated by means of various spectroscopic and spectrometric techniques. Extract and isolated compounds were devoid of inhibitory action against the herein selected bacterial strains (MICs > 256 μg/mL) but showed capacities to reduce 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical (EC50 < 3 μg/mL) considerably better than the …

Microwave-Assisted Synthesis of New Selenazole Derivatives with Antiproliferative Activity

New aryl-hydrazinyl-1,3-selenazole and aroyl-hydrazonyl-1,3-selenazoles were synthesized via Hantzsch type condensation reactions of selenosemicarbazides with α-halogenocarbonyl derivatives, under classical versus microwave heating conditions. Excellent yields and shorter reaction times were obtained under irradiation conditions. The structures of the synthesized compounds were assigned based on spectroscopic data (FT-IR, 1 H-NMR), MS and elemental analysis. Selenazole derivatives were screened for their anti-proliferative effects against two leukemia cell lines (CCRF-CEM and HL60) and three carcinoma cell lines (MDA-MB231, HCT116 and U87MG).

Omphalocarpoidone, a new lanostane-type furano-spiro-γ-lactone from the wood of Tridesmostemon omphalocarpoides Engl. (Sapotaceae)

Abstract Phytochemical studies of the wood and the stem bark of Tridesmostemon omphalocarpoides Engl. (Sapotaceae) led to the isolation of omphalocarpoidone (1), a new lanostane-type furano-spiro-γ-lactone together with β-amyrin acetate (2), taraxerol (3), spinasterol (4), lichexanthone (5), epi-catechin (6), spinasterol 3-O-β- d -glucopyranoside (7), tormentic acid (8), and 1,2,3,4-tetrahydronorharman-1-one (9). Their structures were established on the basis of extensive NMR studies, mass spectrometry, and by comparison of the data with those previously reported in the literature. The structure of the new secondary metabolite was later confirmed by X-ray crystallography. Except for spinast…

Cytotoxic benzylbenzofuran derivatives from Dorstenia kameruniana

Abstract Chromatographic separation of the extract of the roots of Dorstenia kameruniana (family Moraceae) led to the isolation of three new benzylbenzofuran derivatives, 2-(p-hydroxybenzyl)benzofuran-6-ol (1), 2-(p-hydroxybenzyl)-7-methoxybenzofuran-6-ol (2) and 2-(p-hydroxy)-3-(3-methylbut-2-en-1-yl)benzyl)benzofuran-6-ol(3) (named dorsmerunin A, B and C, respectively), along with the known furanocoumarin, bergapten (4). The twigs of Dorstenia kameruniana also produced compounds 1–4 as well as the known chalcone licoagrochalcone A (5). The structures were elucidated by NMR spectroscopy and mass spectrometry. The isolated compounds displayed cytotoxicity against the sensitive CCRF-CEM and …

Cytotoxicity of an unprecedented brominated oleanolide and a new furoceramide from the Cameroonian spice, Echinops giganteus

A preliminary study on Echinops giganteus (Asteraceae) showed that the methanolic extract has interesting cytotoxicities against a panel of cancer cell lines. From this extract, a lignan, a flavonoid and a polyacetylenic thiophene identified were three times less cytotoxic than the extract. In the search of the metabolites responsible for the bioactivity, a new harvested E. giganteus was subjected to a phytochemical study using chromatographic methods. In the course of the work, two new compounds: a brominated oleanolide (1) and a tetrahydrofurano-ceramide (2) were obtained along with β-amyrin acetate (3), 2-(penta-1,3-diynyl)-5-(4-hydroxybut-1-ynyl)-thiophene (4), 2-(penta-1,3-diynyl)-5-(3…

Cytotoxicity of a naturally occuring spirostanol saponin, progenin III, towards a broad range of cancer cell lines by induction of apoptosis, autophagy and necroptosis

Abstract This study was aimed to investigate the cytotoxic potential of a natural compound, progenin III on a broad range of cancer cell lines, including various sensitive and drug-resistant phenotypes. The cytotoxicity, progenin III-induced autophagic, ferroptotic and necroptotic cell death were evaluated by the resazurin reduction assay (RRA). Spectrophotometric analysis of caspases activity was performed using caspase-Glo assay. Flow cytometry was applied for cell cycle analysis (PI staining), apoptosis (annexin V/PI staining), mitochondrial membrane potential (MMP) (JC-1) and reactive oxygen species (ROS) (H2DCFH-DA). Progenin III and the reference molecule, doxorubicin exerted cytotoxi…

A new polyketide from the bark of Hypericum roeperianum Schimp. (Hypericaceae)

The isolation and spectroscopic data of a hitherto undescribed polyketide (1) from Hypericum roeperianum Schimp. (Hypericaceae) together with six known compounds (2–7) is herein reported. The structure elucidation is based on extensive 1D- and 2D-NMR, infrared, UV and MS experiments. The structures of the known compounds were confirmed by comparison of their spectroscopic data with those of similar reported compounds in the literature. Some of the isolated compounds had a significant activity against a panel of multidrug-resistant bacterial strains.

Cytotoxicity and modes of action of three naturally occurring xanthones (8-hydroxycudraxanthone G, morusignin I and cudraxanthone I) against sensitive and multidrug-resistant cancer cell lines

Abstract Background Resistance of cancer to chemotherapy remains a challenging issue for scientists as well as physicians. Naturally occurring xanthones possess a variety of biological activities such as anti-inflammatory, anti-bacterial, and anti-cancer effects. The present study was aimed at investigating the cytotoxicity and the modes of action of three naturally occurring xanthones namely, morusignin I (1), 8-hydroxycudraxanthone G (2) and cudraxanthone I (3) against a panel of nine cancer cell lines, including various sensitive and drug-resistant phenotypes. Methods The cytotoxicity of the compounds was determined using a resazurin reduction assay, whereas the caspase-Glo assay was use…

Cytotoxic Compounds from the Fruits of Uapaca togoensis towards Multifactorial Drug-Resistant Cancer Cells

Cancer cells may rapidly acquire multidrug resistance, mainly due to the presence of adenosine triphosphate-binding cassette transporters, epidermal growth factor receptor, or mutations in the p53 tumor suppressor gene. This work was designed to assess the cytotoxicity of the methanol crude extracts and compounds from the fruits of Uapaca togoensis, namely, β-amyryl acetate (1), 11-oxo-α-amyryl acetate (2), lupeol (3), pomolic acid (4), futokadsurin B (5), arborinin (6), and 3-O-β-D-glucopyranosyl sitosterol (7) against nine drug sensitive and multidrug-resistant cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of the fruits of U. togoensis and compound…

Potential of Central, Eastern and Western Africa Medicinal Plants for Cancer Therapy: Spotlight on Resistant Cells and Molecular Targets

Cancer remains a major health hurdle worldwide and has moved from the third leading cause of death in the year 1990 to second place after cardiovascular disease since 2013. Chemotherapy is one of the most widely used treatment modes; however, its efficiency is limited due to the resistance of cancer cells to cytotoxic agents. The present overview deals with the potential of the flora of Central, Eastern and Western African (CEWA) regions as resource for anticancer drug discovery. It also reviews the molecular targets of phytochemicals of these plants such as ABC transporters, namely P-glycoprotein (P-gp), multi drug-resistance-related proteins (MRPs), breast cancer resistance protein (BCRP,…

Cytotoxic phytochemicals from the crude extract of Tetrapleura tetraptera fruits towards multi-factorial drug resistant cancer cells.

Abstract Ethnopharmacological relevance Tetrapleura tetraptera is an African medicinal spice used in traditional medicine to treat several ailments including cancer. Aim of the study The present study was designed to evaluate the cytotoxicity of the dichloromethane-methanol (1:1) extract of the fruits of Tetrapleura tetraptera (TTF) and its constituents: (3R, 4S)-3,4-dimethyloxetan-2-one (1), luteolin (2), stigmasterol (4), 3-O-[6′-O-undecanoyl-β-D-glucopyranosyl]stigmasterol (6), olean-12-en-3-β-O-D-glucopyranoside (7), 3-O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosylurs-12-en-28-oic acid (8), 3-O-β-D-glucopyranosyl-(1 → 3)-β-D-glucopyranosyl-27-hydroxyolean-12-ene-28-oic acid (9), methyl…

Botanicals and phytochemicals from the bark of Hypericum roeperianum (Hypericaceae) had strong antibacterial activity and showed synergistic effects with antibiotics against multidrug-resistant bacteria expressing active efflux pumps

Abstract Ethnopharmacological relevance Infections due to multidrug-resistant (MDR) bacteria constitute a real problem in the public health worldwide. Hypericum roeperianum Schimp. ex A. Rich (Hypericaceae) is used traditionally for treatment of various ailments such as abdominal pains, constipation, diarrhea, indigestion, nausea, and bacterial diseases. Aim of the study This study was aimed at investigating the antibacterial and antibiotic-modifying activity of the crude methanol extracts (HRB), ethyl-acetate soluble fraction (HRBa), residual material (HRBb), and 11 compounds from the bark of Hypericum roeperianum against multi-drug resistant (MDR) bacteria expressing active efflux pumps. …

Cytotoxicity of 91 Kenyan indigenous medicinal plants towards human CCRF-CEM leukemia cells.

Abstract Ethnopharmacological relevance Plants from Kenyan flora are traditionally used against many ailments, including cancer and related diseases. Cancer is characterized as a condition with complex signs and symptoms. Recently there are recommendations that ethnopharmacological usages such as immune and skin disorders, inflammatory, infectious, parasitic and viral diseases should be taken into account when selecting plants that treat cancer. Aim The present study was aimed at investigating the cytotoxicity of a plethora of 145 plant parts from 91 medicinal plants, most of which are used in the management of cancer and related diseases by different communities in Kenya, against CCRF-CEM …

Activity of three cytotoxic isoflavonoids from Erythrina excelsa and Erythrina senegalensis (neobavaisoflavone, sigmoidin H and isoneorautenol) toward multi-factorial drug resistant cancer cells

Abstract Introduction Resistance of cancer cells to chemotherapy has become a worldwide concern. Naturally occuring isoflavonoids possess a variety of biological activities including anti-cancer effects. The present study was aimed at investigating the cytotoxicity and the modes of action of three naturally occuring isoflavonoids, neobavaisoflavone ( 1 ), sigmoidin H ( 2 ) and a pterocarpan that is a special type of isoflavonoid, isoneorautenol ( 3 ) against a panel of nine cancer cell lines, including various sensitive and drug-resistant phenotypes. Methods The cytotoxicity of the compounds was determined using a resazurin reduction assay, whereas the caspase-Glo assay was used to detect t…

Cytotoxicity of some Cameroonian spices and selected medicinal plant extracts

Abstract Ethnopharmacological relevance Several medicinal plants and spices are used traditionally to treat cancers in Cameroon. Aim Methanol extracts from thirty-four spices and plants, with related ethnobotanical use were investigated for their in vitro cytotoxicity on the human pancreatic cancer cell line MiaPaCa-2, leukemia CCRF-CEM cells and their multidrug resistant (MDR) subline CEM/ADR5000, and the normal human umbilical vein endothelial cells (HUVECs). In addition the anti-angiogenic properties of the most active extracts were investigated. Material and methods The MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay was used for cyto…

Quinones and Benzophenones from the Medicinal Plants of Africa

In this chapter, we discuss the chemistry of quinones and benzophenones: classification, nomenclature, biosynthesis, biological activity, and their distribution in nature. Genera such as Newbouldia, Kigelia, Aloe, Euclea, Diospyros, Bulbine, Rumex, and Kniphofia are rich sources of quinines, while the Guttiferae are rich in polyprenylated benzophenones. Most of these African species offer novel derivatives with interesting biological activities, suggesting that these species are potential sources of new drug candidates if properly investigated.

Cytotoxicity and modes of action of five Cameroonian medicinal plants against multi-factorial drug resistance of tumor cells

Abstract Ethnopharmacological relevance Beilschmiedia acuta Kosterm, Clausena anisata (Willd) Hook, Fagara tessmannii Engl., Newbouldia laevis Seem., and Polyscias fulva (Hiern) Harms. are medicinal plants used in Cameroonian traditional medicine in the treatment of various types of cancers. The present study aims at investigating 11 methanolic extracts from the above Cameroonian medicinal plants on a panel of human cancer cell lines, including various drug-resistant phenotypes. Possible modes of action were analyzed for two extracts from Beilschmiedia acuta and Polyscia fulva and alpha-hederin, the representative constituent of Polyscia fulva. Materials and methods Cytotoxicity was determi…

Saponin with antibacterial activity from the roots of Albizia adianthifolia

An unprecedented saponin is being reported herein together with five known compounds from the methanol extract of the roots of Albizia adianthifolia. The metabolites were obtained over repeated open column chromatography methods and spectroscopic followed by spectrometric techniques. The isolated compounds were tested against eleven Gram-negative bacteria including multidrug resistant strains. The results revealed considerable inhibition of the new saponin against the studied bacteria with MIC values ranging from 16 to 128 μg/mL.

8,8-bis-(Dihydroconiferyl)-diferulate displayed impressive cytotoxicity towards a panel of human and animal cancer cells

Abstract Background Recalcitrant cancers appear as a major obstacle to chemotherapy, prompting scientists to intensify the search for novel drugs to tackle the cell lines expressing multi-drug resistant (MDR) phenotypes. Purpose The purpose of this study was to evaluate the antiproliferative potential of a ferrulic acid derivative, 8,8-bis-(dihydroconiferyl)-diferulate (DHCF2) on a panel of 18 cancer cell lines, including various sensitive and drug-resistant phenotypes, belonging to human and animals. The mode of induction of cell death by this compound was further studied. Methods The antiproliferative activity, autophagy, ferroptotic and necroptotic cell death were evaluated by the resazu…

Cytotoxicity of ungeremine towards multi-factorial drug resistant cancer cells and induction of apoptosis, ferroptosis, necroptosis and autophagy

Abstract Background Successful cancer chemotherapy is hampered by resistance of cancer cells to established anticancer drugs. Numerous natural products reveal cytotoxicity towards tumor cells. Purpose The present study was aimed to determine the cytotoxicity of a betaine-type alkaloid, ungeremine, towards 9 cancer cell lines including various sensitive and drug-resistant phenotypes. The mode of action of this compound was further investigated. Methods The cytotoxicity, ferroptotic and necroptotic cell death were determined by the resazurin reduction assay. Caspase activation was evaluated using the caspase-Glo assay. Flow cytometry was applied for the analysis of cell cycle analysis (PI sta…

Cameroonian Medicinal Plants: Pharmacology and Derived Natural Products

Many developing countries including Cameroon have mortality patterns that reflect high levels of infectious diseases and the risk of death during pregnancy and childbirth, in addition to cancers, cardiovascular diseases and chronic respiratory diseases that account for most deaths in the developed world. Several medicinal plants are used traditionally for their treatment. In this review, plants used in Cameroonian traditional medicine with evidence for the activities of their crude extracts and/or derived products have been discussed. A considerable number of plant extracts and isolated compounds possess significant antimicrobial, anti-parasitic including antimalarial, anti-proliferative, a…

Prospecting for cytotoxic and antiprotozoal 4-aryl-4H-chromenes and 10-aryldihydropyrano[2,3-f]chromenes.

Different studies reported that genetic predisposition or metabolic dysfunction are the risk factors for cancer. Infectious parasitic diseases were listed among factors that predispose to cancer. Because of the resemblance between the life cycle of cancer cells and some parasites, this study aimed to prepare pyran derivatives with cytotoxic and antiprotozoal potencies. Therefore, 7 chromenes, 10 pyranocoumarins, and an unexpected intermediate were obtained from a multi-reagent one-pot reaction. These compounds were evaluated for their cytotoxicity on sensitive and resistant leukemia cancer cells lines and against two protozoan parasites, namely Trypanosoma cruzi and Leishmania amazonensis a…

Cytotoxicity, anti-angiogenic, apoptotic effects and transcript profiling of a naturally occurring naphthyl butenone, guieranone A

Abstract Background Malignant diseases are responsible of approximately 13% of all deaths each year in the world. Natural products represent a valuable source for the development of novel anticancer drugs. The present study was aimed at evaluating the cytotoxicity of a naphtyl butanone isolated from the leaves of Guiera senegalensis, guieranone A (GA). Results The results indicated that GA was active on 91.67% of the 12 tested cancer cell lines, the IC50 values below 4 μg/ml being recorded on 83.33% of them. In addition, the IC50 values obtained on human lymphoblastic leukemia CCRF-CEM (0.73 μg/ml) and its resistant subline CEM/ADR5000 (1.01 μg/ml) and on lung adenocarcinoma A549 (0.72 μg/m…

Cytotoxicity of botanicals and isolated phytochemicals from Araliopsis soyauxii Engl. (Rutaceae) towards a panel of human cancer cells.

Abstract Ethnopharmacological relevance Araliopsis soyauxii Engl. (Rutaceae) is a Cameroonian medicinal plant traditionally used to treat lung diseases, malaria, and gonorrhea. It has been demonstrated that infectious disease contribute to about 20% of all human tumours. Aims of the study (1) To perform a phytochemical investigation of the dichloromethane-methanol 1:1 extracts of the bark (ASB), roots (ASR), and leaves (ASL) from Araliopsis soyauxii; (2) to evaluate the cytotoxicity of extracts and isolated compounds; (3) to determine the mode of induction of apoptosis of ASB and kihadanin B (12). Materials and methods Fourteen constituents of the crude extracts were isolated by column chro…

Cytotoxicity of epunctanone and four other phytochemicals isolated from the medicinal plants Garcinia epunctata and Ptycholobium contortum towards multi-factorial drug resistant cancer cells.

Abstract Introduction Resistance of cancer cells is a serious impediment to chemotherapy and several phytochemicals are active against multi-drug resistant (MDR) phenotypes. The cytotoxicity of five naturally occurring compounds: betulin (1), mundulea lactone (2), seputhecarpan A (3), seputheisoflavone (4) and epunctanone (5) was evaluated on a panel of 9 cancer cell lines including various sensitive and drug-resistant cell lines. The modes of action of compound 5 were further investigated. Methods The resazurin reduction assay was used to evaluate cytotoxicity of samples and ferroptotic cell death induced by compound 5; caspase-Glo assay was used to detect the activation of caspases in CCR…

Antibacterial activity and cytotoxicity of selected Egyptian medicinal plants.

Medicinal plants have been used as a source of remedies since ancient times in Egypt. The present study was designed to investigate the antibacterial activity and the cytotoxicity of the organic extracts from 16 selected medicinal plants of Egypt. The study was also extended to the isolation of the antiproliferative compound jaeschkeanadiol p-hydroxybenzoate (FH-25) from Ferula hermonis. The microbroth dilution was used to determine the minimal inhibitory concentration (MIC) of the samples against twelve bacterial strains belonging to four species, Providencia stuartii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli, while a resazurin assay was used to assess the cytoto…

Cytotoxicity of isoflavones and biflavonoids from Ormocarpum kirkii towards multi-factorial drug resistant cancer.

Abstract Background While incidences of cancer are continuously increasing, drug resistance of malignant cells is observed towards almost all pharmaceuticals. Several isoflavonoids and flavonoids are known for their cytotoxicity towards various cancer cells. Purpose The aim of this study was to determine the cytotoxicity of isoflavones: osajin (1), 5,7-dihydroxy-4ˈ-methoxy-6,8-diprenylisoflavone (2) and biflavonoids: chamaejasmin (3), 7,7″-di-O-methylchamaejasmin (4) and campylospermone A (5), a dimeric chromene [diphysin(6)] and an ester of ferullic acid with long alkyl chain [erythrinasinate (7)] isolated from the stem bark and roots of the Kenyan medicinal plant, Ormocarpum kirkii. The m…

Biopiracy of natural products and good bioprospecting practice

Made available in DSpace on 2018-11-26T16:27:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-02-15 Deutsche Forschungsgemeinschaft Background: Biopiracy mainly focuses on the use of biological resources and/or knowledge of indigenous tribes or communities without allowing them to share the revenues generated out of economic exploitation or other non-monetary incentives associated with the resource/knowledge. Methods: Based on collaborations of scientists from five continents, we have created a communication platform to discuss not only scientific topics, but also more general issues with social relevance. This platform was termed 'PhytCancer -Phytotherapy to Fight Cancer' (www.phy…

A naturally occuring triterpene saponin ardisiacrispin B displayed cytotoxic effects in multi-factorial drug resistant cancer cells via ferroptotic and apoptotic cell death

WOS: 000432722700010

Cytotoxicity of two naturally occurring flavonoids (dorsmanin F and poinsettifolin B) towards multi-factorial drug-resistant cancer cells.

Abstract Introduction The expression of diverse resistance mechanisms in cancer cells is one of the major barriers to successful cancer chemotherapy. Methods In the present study, we assessed the cytotoxicity of two naturally occurring flavonoids dorsmanin F ( 1 , a flavanone) and poinsettifolin B ( 2 , a chalcone) against 9 drug-sensitive and multidrug-resistant (MDR) cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of these compounds, whilst caspase-Glo assay was used to detect caspase activation. Cell cycle, mitochondrial membrane potential (MMP) and levels of reactive oxygen species (ROS) were all analysed via flow cytometry. Results Compounds 1 and…

Collateral sensitivity of drug-resistant ABCB5- and mutation-activated EGFR overexpressing cells towards resveratrol due to modulation of SIRT1 expression.

Abstract Background In the drug discovery field, natural products deemed a precious source of novel lead compounds. They have the ability to bypass or overcome multidrug resistance (MDR) in cancer cells. Purpose In this study, the natural polyphenolic stilbene resveratrol (RES) has been studied for its cytotoxic activity toward MDR cancer cells. Methods Resazurin assay was used to investigate the cytotoxicity of RES not only against a panel of drug-resistant cancer cells overexpressing P-glycoprotein/ABCB1, BCRP/ABCG2, ABCB5 (ATP-binding cassette transporters), but also mutation-activated EGFR. The assessment of proteins expression was done by Western blot analysis. COMPARE and hierarchical…

Cytotoxic flavonoids from two Lonchocarpus species

A new isoflavone, 4′-prenyloxyvigvexin A (1) and a new pterocarpan, (6aR,11aR)-3,8-dimethoxybitucarpin B (2) were isolated from the leaves of Lonchocarpus bussei and the stem bark of Lonchocarpus eriocalyx, respectively. The extract of L. bussei also gave four known isoflavones, maximaisoflavone H, 7,2′-dimethoxy-3′,4′-methylenedioxyisoflavone, 6,7,3′-trimethoxy-4′,5′-methylenedioxyisoflavone, durmillone; a chalcone, 4-hydroxylonchocarpin; a geranylated phenylpropanol, colenemol; and two known pterocarpans, (6aR,11aR)-maackiain and (6aR,11aR)-edunol. (6aR,11aR)-Edunol was also isolated from the stem bark of L. eriocalyx. The structures of the isolated compounds were elucidated by spectrosco…

N-acetylglycoside of oleanolic acid (aridanin) displays promising cytotoxicity towards human and animal cancer cells, inducing apoptotic, ferroptotic and necroptotic cell death

Abstract Background The discovery of novel phytochemicals represents a reasonable approach to fight malignancies, especially those which are resistant to standard chemotherapy. Purpose We evaluated the cytotoxic potential of a naturally occurring N-acetylglycoside of oleanolic acid, aridanin, on 18 cancer cell lines, including sensitive and drug-resistant phenotypes mediated by P-glycoprotein, BCRP, p53 knockout, deletion-mutated EGFR, or BRAF mutations. Furthermore, metastasizing B16/F10 cells, HepG2 hepatocarcinoma and normal AML12 hepatocytes were investigated. The mechanisms of aridanin-induced cell death was further investigated. Methods The resazurin reduction assay (RRA) was applied …

Cytotoxicity and modes of action of 4'-hydroxy-2',6'-dimethoxychalcone and other flavonoids toward drug-sensitive and multidrug-resistant cancer cell lines.

Abstract Introduction Resistance of cancer to chemotherapy is a main cause in treatment failure. Naturally occurring chalcones possess a wide range of biological activities including anti-cancer effects. In this work, we evaluated the antiproliferative activity of three chalcones [4′-hydroxy-2′,6′-dimethoxychalcone ( 1 ), cardamomin ( 2 ), 2′,4′-dihydroxy-3′,6′-dimethoxychalcone ( 3 )], and four flavanones [( S )-(–)-pinostrobin ( 4 ), ( S )-(–)-onysilin ( 5 ) and alpinetin ( 6 )] toward nine cancer cell lines amongst which were multidrug resistant (MDR) types. Methods The resazurin reduction assay was used to detect the antiproliferative activity of the studied samples whilst flow cytometr…

Harmful and Protective Effects of Terpenoids from African Medicinal Plants

Terpenoids represent the most widespread group of natural products and can be found in all classes of living things. Many defensive compounds include sesquiterpenoids and diterpenoids from angiosperm species. Several terpenoids are biologically active and are exploited in the fight against cancer, malaria, inflammation, and a variety of infectious diseases. Nonetheless, some compounds of this group showed toxic effects causing gastrointestinal problems or central nervous system manifestations among others. Several bioactive terpenoids were identified in African medicine with numbers of them having organ-protective effects while few are known for their nonbeneficial properties for humans. In…

Synthesis of Functionalized 1‐Aryl‐3‐phenylthiazolylpropanoids and Their Potential as Anticancer Agents

A new polyketide from the bark of Hypericum roeperianum Schimp. (Hypericaceae)

The isolation and spectroscopic data of a hitherto undescribed polyketide (1) from Hypericum roeperianum Schimp. (Hypericaceae) together with six known compounds (2–7) is herein reported. The struc...

Collateral sensitivity of natural products in drug-resistant cancer cells

Cancer chemotherapy is frequently hampered by drug resistance. Concepts to combine anticancer drugs with different modes of action to avoid the development of resistance did not provide the expected success in the past, because tumors can be simultaneously non-responsive to many drugs (e.g. the multidrug resistance phenotype). However, tumors may be specifically hypersensitive to other drugs - a phenomenon also termed collateral sensitivity. This seems to be a general biological mechanism, since it also occurs in drug-resistant Escherichia coli and Saccharomyces cerevisiae. Here, we give a timely and comprehensive overview on hypersensitivity in resistant cancer cells towards natural produc…

Biopiracy versus One-World Medicine-From colonial relicts to global collaborative concepts.

Abstract Background Practices of biopiracy to use genetic resources and indigenous knowledge by Western companies without benefit-sharing of those, who generated the traditional knowledge, can be understood as form of neocolonialism. Hypothesis The One-World Medicine concept attempts to merge the best of traditional medicine from developing countries and conventional Western medicine for the sake of patients around the globe. Study design Based on literature searches in several databases, a concept paper has been written. Legislative initiatives of the United Nations culminated in the Nagoya protocol aim to protect traditional knowledge and regulate benefit-sharing with indigenous communiti…

Steroidal saponins from Raphia vinifera and their cytotoxic activity

Abstract Phytochemical analysis of the fruits of Raphia vinifera led to the isolation of four new steroidal saponins (1–4), along with six known secondary metabolites (6–10). The structures of the isolated compounds were determined based on the analyses of NMR and mass spectrometric data, and chemical degradation reactions. Among the compounds tested, 1 and 4 showed the most promising cytotoxic activity against the drug-sensitive CCRF-CEM leukemia cell lines, with IC50 values of 3.55 µM and 7.14 µM, respectively.

Oridonin Targets Multiple Drug-Resistant Tumor Cells as Determined by in Silico and in Vitro Analyses

Drug resistance is one of the main reasons of chemotherapy failure. Therefore, overcoming drug resistance is an invaluable approach to identify novel anticancer drugs that have the potential to bypass or overcome resistance to established drugs and to substantially increase life span of cancer patients for effective chemotherapy. Oridonin is a cytotoxic diterpenoid isolated from Rabdosia rubescens with in vivo anticancer activity. In the present study, we evaluated the cytotoxicity of oridonin toward a panel of drug-resistant cancer cells overexpressing ABCB1, ABCG2, or ΔEGFR or with a knockout deletion of TP53. Interestingly, oridonin revealed lower degree of resistance than the control dr…

Pharmacogenomic and molecular docking studies on the cytotoxicity of the natural steroid wortmannin against multidrug-resistant tumor cells

Wortmannin is a cytotoxic compound derived from the endophytic fungi Fusarium oxysporum, Penicillium wortmannii and Penicillium funiculosum that occurs in many plants, including medicinal herbs. The rationale to develop novel anticancer drugs is the frequent development of tumor resistance to the existing antineoplasic agents. Therefore, it is mandatory to analyze resistance mechanisms of novel drug candidates such as wortmannin as well to bring effective drugs into the clinic that have the potential to bypass or overcome resistance to established drugs and to substantially increase life span of cancer patients. In the present project, we found that P-glycoprotein-overexpressing tumor cells…

The alkaloid, soyauxinium chloride, displays remarkable cytotoxic effects towards a panel of cancer cells, inducing apoptosis, ferroptosis and necroptosis.

Abstract The cytotoxic potential of a naturally occurring indoloquinazoline alkaloid, soyauxinium chloride (SCHL), was determined on a broad panel of animal and human cancer cell lines, including various sensitive and drug-resistant phenotypes. The cytotoxicity, SCHL-induced autophagic, ferroptotic, and necroptotic cell death were evaluated by the resazurin reduction assay (RRA). Caspase-Glo assay was used to detect the activity of caspases using spectrophotometric analysis. Flow cytometry was applied for cell cycle analysis (PI staining), apoptosis (annexin V/PI staining), mitochondrial membrane potential (MMP) (JC-1) and reactive oxygen species (ROS) (H2DCFH-DA). SCHL and doxorubicin (ref…

&lt;b&gt;ANTIMICROBIAL DITERPENOID ALKALOIDS FROM &lt;i&gt;ERYTHROPHLEUM SUAVEOLENS&lt;/i&gt; (GUILL. &amp; PERR.) BRENAN&lt;/b&gt;

An investigation of the stem bark of Erythrophleum suaveolens (Guill. & Perr.) Brenan yielded the known amide norcassaide ( 1 ) and a new diterpenoid alkaloid named norerythrosuaveolide ( 2 ) which was characterized as 7β-hydroxy-7-deoxo-6-oxonorcassaide. The structures were established on the basis of one and two-dimensional 1 H and 13 C NMR spectral data. The compounds showed potent antimicrobial activities against bacteria and yeasts. KEY WORDS: Erythrophleum suaveolens (Guill. & Perr.) Brenan, Norcassaide, Diterpenoid alkaloid, Norerythrosuaveolide, Antimicrobial activities, Bacteria, Yeasts Bull. Chem. Soc. Ethiop. 2005, 19(2), 221-226.

Cytotoxicity and mode of action of a naturally occurring naphthoquinone, 2-acetyl-7-methoxynaphtho[2,3-b]furan-4,9-quinone towards multi-factorial drug-resistant cancer cells

Abstract Introduction Malignacies are still a major public concern worldwide and despite the intensive search of new chemotherapeutic agents, treatment still remains a challenging issue. The present study was designed to evaluate the cytotoxicity of 2-acetyl-7-methoxynaphtho[2,3-b]furan-4,9-quinone (AMNQ) isolated from the bark of Milletia versicolor towards a panel of drug-sensitive and multidrug-resistant (MDR) cancer cell lines. Methods The resazurin reduction assay was used to evaluate the cytotoxicity of AMNQ against 9 drug-sensitive and multidrug-resistant (MDR) cancer cell lines. Cell cycle, mitochondrial membrane potential (MMP) and levels of reactive oxygen species were all analyze…

CCDC 942767: Experimental Crystal Structure Determination

Related Article: Chi G. Fru, Louis P. Sandjo, Victor Kuete, Johannes C. Liermann, Dieter Schollmeyer, Samuel O. Yeboah, Renameditswe Mapitse, Berhanu M. Abegaz, Bonaventure T. Ngadjui, Till Opatz|2013|Phytochem.Lett.|6|676|doi:10.1016/j.phytol.2013.08.017