0000000001182675
AUTHOR
Gabin Thierry M. Bitchagno
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...
Constituents of Peperomia vulcanica Baker & C. H. Wright (Piperaceae) with antiparasitic activity
Abstract The investigation of the CH2Cl2-MeOH (1:1) extract of Peperomia vulcanica which showed antileishmanial activity during preliminary screening led to the isolation of two previously unknown compounds named peperolignan (1) and peperotannin (2) along with 13 known compounds. Their structures were determined on the basis of their spectroscopic data. The isolated compounds were assessed in vitro for their antileishmanial and antiplasmodial activities against Leishmania donovani 1S (MHOM/SD/62/1S) promastigotes and the Plasmodium falciparum chloroquine-sensitive 3D7 strain (Pf3D7), respectively. They were also assessed for their cytotoxicity on Raw 264.7 macrophage cells. The mixture of …
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…
A new ceramide from the leaves of Lannea schimperi (Hochst. ex A.Rich.) Engl.
A new ceramide is being reported herein together with six known compounds from the methanol extract of the leaves of Lannea schimperi (Hochst. ex A.Rich.) Engl. The metabolites were obtained through repeated open column chromatography and were characterized by spectroscopic and spectrometric techniques. The radical-scavenging activity of the crude extract and isolated compounds was evaluated using the DPPH radical. The obtained results suggest the studied species as prominent candidate to fight reactive oxygen species (ROS).
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).
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 …
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.
Neo-clerodane diterpenoids from Conyza pyrrhopappa Sch.Bip. ex A.Rich
Two hitherto unknown neo-clerodane-type diterpenoids along with twelve known compounds have been isolated from Conyza pyrrhopappa Sch.Bip. ex A.Rich, a medicinal plant traditionally used across tropical Africa to relieve fever. The structures of isolates have been elucidated by a combination of spectroscopic techniques. The crude extract and the isolated compounds were evaluated in the Hela-S3 cell line and in a panel of microorganisms (bacteria and fungi) at concentrations up to 50 ��g/mL. The new compounds were inactive while the pentamethylated flavonoids showed low to significant activity against the cancer cell line used. However, none of the samples showed any activity against the tes…
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. …
Chemical constituents, total phenolic content, antioxidant activity and bactericidal effect of Dicliptera verticillate (Acanthaceae)
Abstract This study investigated the phytochemical constituents and evaluated the total phenolic content, it also determined the antioxidant and antibacterial activities of the ethanol (EtOH) extract of the whole plant of Dicliptera verticillata. The phytochemical study was carried out using repeated silica gel column chromatography followed by Sephadex LH-20 to purify the extract which afforded three known compounds: lutein (1), shikimic acid (2) and guaiacylglycerol (3). The structures of these compounds were identified after analyses of their NMR and MS data and comparison of these data with those reported in the literature. The antioxidant and antibacterial activities were evaluated by …
Neo-clerodane diterpenoids from Conyza pyrrhopappa Sch.Bip. ex A.Rich
Two hitherto unknown neo-clerodane-type diterpenoids along with twelve known compounds have been isolated from Conyza pyrrhopappa Sch.Bip. ex A.Rich, a medicinal plant traditionally used across tropical Africa to relieve fever. The structures of isolates have been elucidated by a combination of spectroscopic techniques. The crude extract and the isolated compounds were evaluated in the Hela-S3 cell line and in a panel of microorganisms (bacteria and fungi) at concentrations up to 50 µg/mL. The new compounds were inactive while the pentamethylated flavonoids showed low to significant activity against the cancer cell line used. However, none of the samples showed any activity against the test…
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…
New Alkenylresorcinols with Cytotoxic and Antimicrobial Activities from the Leaves of Embelia schimperi.
AbstractA phytochemical study of the methanol extract of the leaves of Embelia schimperi resulted in the isolation of three new alkenylresorcinols, 1 – 3, together with the known analogs 4 – 7. Their structures were established by a combination of spectroscopic techniques. Compounds 1 – 7 exhibited moderate cytotoxic activity against human cervical cancer cells HeLa-S3 and more pronounced antimicrobial properties towards bacteria and filamentous fungi. The present study falls into an ongoing research project on the characterization of bioactive phenolic lipids from plants of the family Primulaceae.
C-28/C-30 oxidized cycloartanes from the leaves and twigs of Caloncoba dusenii Gilg
Abstract Four hitherto unreported cycloartane-type triterpenes (1-4) with C-28/C-30 oxidized methyl groups together with two known compounds (5-6) have been obtained from the leaves and twigs of Caloncoba dusenii Gilg. The compounds were isolated through extraction and silica gel column chromatography. Their structures and relative stereochemistry were determined by extensive use of spectroscopic techniques including IR, 1D and 2D-NMR as well as mass spectrometry. This is the first report of C-28/C-30 oxidized positions in cycloartanes from nature.
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...
A new ceramide from the leaves of Lannea schimperi (Hochst. ex A.Rich.) Engl.
A new ceramide is being reported herein together with six known compounds from the methanol extract of the leaves of Lannea schimperi (Hochst. ex A.Rich.) Engl. The metabolites were obtained through repeated open column chromatography and were characterized by spectroscopic and spectrometric techniques. The radical-scavenging activity of the crude extract and isolated compounds was evaluated using the DPPH radical. The obtained results suggest the studied species as prominent candidate to fight reactive oxygen species (ROS).