Alchornea Floribunda Research Articles

The best African plant-derived antibacterial products for clinical perspectives: The state-of-the-art

Background: The global burden of bacterial infections remains a serious health concern. In the present review, we have summarized the best botanicals and phytochemicals from the flora of Africa that deserve clinical studies to develop novel antibacterial drugs to combat enterobacteria, Pseudomonas aeruginosa, Gram-positive bacteria, and mycobacteria. Methods: Data were retrieved from scientific databases such as PubMed, Scopus, ScienceDirect, Google Scholar, and Web of Science using the keywords “African country and plant and antibacterial” and plants or phytochemicals with outstanding antibacterial activities following established cutoff point standards were selected. Results: The identified botanicals were from Acacia polyacantha, Alchornea floribunda, Artemisia abyssinica, Beilschmiedia acuta, Eriosema glomeratum, Harungana madagascariensis, Macaranga capensis, Macaranga conglomerata, Macaranga kilimandscharica, Mangifera indica, Piper nigrum, Piptadeniastrum africanum, and Uapaca togoensis. The phytochemicals identified included 2-(4-hydroxyphenyl)-ethyltriacontanoate (1), 1,3,5,6-tetrahydroxyxanthone (2), 1,3,5,7-tetrahydroxyxanthone (3), 8,8-bis-(dihydroconiferyl) diferulate (4), 2-hydroxy-3-methoxy-9,10-dioxo-9,10-dihydroanthracene-1-carbaldehyde (5), allanxanthone D (6), angusticornin B (7), bartericin A (8), diospyrone (9), dorsmanin C (10), gancaonin Q (11), isobavachalcone (12), isoliquiritigenin (13), laburnetin (14), O1-demethyl-3',4'-deoxy-psorospermi-3',4' diol (15), plumbagin (16), and vismiaquinone (17). Conclusion: These plant-derived products deserve clinical investigations to develop novel antibacterial agents to combat bacterial infections.

Species Composition and Structure of Habitats Exploited by Elephants (Loxodonta Africana Cyclotis) in the Campo Maan Forest, South Region, Cameroon

Purpose: The main objective of this study was to determine the species composition and structure of habitats exploited by elephants in the Campo Maan Forest.
 Methodology: Using the transect methods, purposively, 1km transects were laid along identified feeding tracts in various habitats. 15 transects with each having 4 quadrates of 30x30m were established at interval of 220m summing up to a total of 5.4 hectares of land covered for the study within which data was collected. In the quadrates, all vascular plants with dbh >10cm (diameter at breast height about 1.3m above the ground) were measured and identified. In each quadrate, four subplots of 15mx15m were placed at the corners to sample understory and herbs.
 Findings: Results reveal a total of 1113 individual trees with DBH of ≥ 10 cm identified and measured belong to 49 species from 24 families. Fabaceae was the most dominant family of plants with 425 individual trees counted with Caesalpinioideae being the dominant specie type (116); followed by Calpocalyx heitzii (92). Lowland evergreen forest (Casalpinioideae) recorded the highest number of tree species counted (462, 41.5%) of the total tree species. Trees DBH varies between 10 and 64 cm with mean values of 29.45±11.48 cm, 23.3±7.759 cm, 27.69±9.189 cm and 25.75±14.056 cm for Lowland evergreen forest (Casalpinioideae), Lowland evergreen forest (mixed), Coastal forest (Sacoglotis gabonensis) and Coastal forest (mixed) respectively. A large number of trees recorded heights of above 30m though it was higher for Lowland evergreen forest (mixed), Coastal forest (Sacoglotis gabonensis) and the Coastal forest (mixed). For the understory, the dominant specie types are Scaphopetalum blackii, Palisota ambigua, Asystasia macrophylla, Podococcus barteri, Microdesmis puberula, Heistera pavifora, Haumania danckelmaniana, Alchornea floribunda all counting 9 and 10 individual Trees). Results revealed highly positive and significant correlations between trees DBH and height (r=0.84, p=0.000). The Shannon’s diversity index indicates that the tree diversity for all habitats are fairly even with Coastal forest (Sacoglotis gabonensis) having a value of 4.73. The Coastal forest (mixed) shows the highest rate of basal area (76.39); followed by Coastal forest (Sacoglotis gabonensis) (41.50) and Lowland evergreen forest (Casalpinioideae) (32.26), all indicating high basal areas.
 Recommendation: Further studies on habitat fragmentation are needed to assess its effects on elephant movement within the area.

<i>Alchornea floribunda</i> (Müll. Arg.) - A review of its phytochemistry and biological activities

Alchornea floribunda is an evergreen plant that grows up to 32 feet tall and belongs to the family of Euphorbiaceae. It is found mainly in African forest undergrowth. In Nigeria, its leaves, stems and roots are widely used in folkloric medicine to manage ailments and diseases. The pharmacological activity of A. floribunda depends mainly on the part used. A previous study showed that the leaves have antiinflammatory, antimicrobial, antioxidant and anti-cancer activities, while its roots and stem possess antibacterial activity. Thus, this review takes a critical look at previously reported findings and information about the phytochemistry, biological activities and various isolated bioactive constituents from the leaf, root and stem of Alchornea floribunda.
 Keywords: Alchornea floribunda, Phytochemistry, Inflammatory, Antimicrobial, Antioxidant, Anti-cancer

English

Respiratory syncytial virus (RSV) causes viral infection of a global proportion. Currently, there is no approved vaccine or useful antiviral drug against it. Natural products hold potential for discovery of anti-RSV agents. The present study assessed the anti-RSV activities of Alchornea cordifolia (AC) (Shumach. and Thonn.) MÏ‹ll. Arg. and Alchornea floribunda (AF) MÏ‹ll. Arg., Antiviral activities of AC and AF leaf extracts were evaluated by a modified viral plaque reduction assay. Parallel assays for effect of the antiviral agents on cell viabilities were carried out the cells using the 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) reduction assays. Mechanism of anti-RSV action of the extracts was done based on time-of-addition assay. Extracts of AC and AF, showed anti-RSV activities with IC50 = 5.64 ± 1.16, and 75.62 ± 3.38 µg/ml, respectively while the cell cytotoxic effect of extracts were TC50 = 103.14 ± 3.98, and 333.82 ± 6.32 µg/ml, respectively. Time-of-addition assay results suggested that AC and AF interfere with viral replication at a viral post-entry step. The extracts of AC and AF exhibited profound anti-RSV activities warranting their development for further possible clinical utility against RSV. Key words: Alchornea cordifolia, Alchornea floribunda, respiratory syncytial virus (RSV), antiviral, time-of-addition, cell culture. &nbsp

In vitro and in vivo antioxidant potentials of Alchornea floribunda leaf extract, fractions and isolated bioactive compounds.

Alchornea floribunda leaves are widely used in ethnomedicine for the management of immuno-inflammatory disorders. We investigated the in vivo and in vitro antioxidant activity of the leaf extract, fractions and isolated compounds of A. floribunda. The ethyl acetate fraction of the methanol leaf extract was subjected to several chromatographic separations to isolate compounds 1-4. The structures of the isolated compounds were elucidated by a combination of 1D and 2D NMR and mass spectrometry. Oxidative stress was induced with carbon tetrachloride (CCl4). Further analysis on the isolated phenolic compounds were done using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and hydrogen peroxide scavenging activity tests. The ethyl acetate fraction at 200 mg/kg produced significant (p<0.05) elevations of catalase enzyme activity and a significant (p<0.05) reduction in serum malondialdehyde. The chemical investigation of the ethyl acetate fraction led to the isolation of three flavans, (-) cathechin (1), (-) epicathechin (2), (+) epicathechin (3) and a flavanone, 2R, 3R dihydroquercitin (4). In hydrogen peroxide scavenging assay, (-) epicathechin exhibited an EC50 value of 8 μg/ml, similar to the standard ascorbic acid (EC50 = 8 μg/ml). (-) epicathechin showed scavenging of DPPH radical with EC50 value of 19 μg/ml while in the FRAP assay, it had EC50 value of 46 μg/ml which was lower than that of the standard, ascobic acid (EC50 = 66 μg/ml). The medicinal uses of A. floribunda may be due to the antioxidant activities of its phenolic compounds.

Cytotoxicity of methanol extracts of Annona muricata, Passiflora edulis and nine other Cameroonian medicinal plants towards multi-factorial drug-resistant cancer cell lines.

Background Cancer cells rapidly acquire resistance leading to treatment failures. In the present study, we have evaluated the cytotoxicity of 17 methanol extracts from 11 Cameroonian medicinal plants against the sensitive leukemia CCRF–CEM cells and the best ones were further tested on a panel of 8 other human cancer cell lines, including various MDR phenotypes as well as against the normal AML12 hepatocytes.MethodsThe cytotoxicity of the extracts was determined using a resazurin reduction assay meanwhile flow cytometry was used to measure cell cycle, apoptosis, mitochondrial membrane potential (MMP), and reactive oxygen species.ResultsIn an initial screening using leukemia CCRF–CEM cells, ten extracts from five plants namely Alchornea floribunda, Annona muricata, Euphorbia prostata, Pachypodanthium staudtii and Passiflora edulis displayed IC50 values below 20 µg/mL. They were further tested in 8 other cell lines as well as in normal AML12 hepatocytes. All selected extracts were active against leukemia CEM/ADR5000 cells with IC50 value below 40 µg/mL. IC50 values ranging from 10.13 µg/mL (towards CEM/ADR5000 cells) to 72.01 µg/mL [towards resistant colon carcinoma HCT116 (p53−/−) cells] for Pachypodanthium staudtii roots and from 0.11 µg/mL (towards CCRF–CEM cells) to 108 µg/mL (towards P-glycoprotein-over-expressing CEM/ADR5000 cells) for doxorubicin were obtained in the eight other cancer cell lines studied. Extracts from Annona muricata leaves (AML) and seeds (AMS), and Passiflora edulis fruit (PEF) had IC50 values below 1 µg/mL against CCRF–CEM cells and below 10 µg/mL against its MDR subline CEM/ADR5000 cells. AML, AMS and PEF induced MMP-loss-mediated apoptosis in CCRF–CEM cells.ConclusionsResults of the present study suggest that some of the tested plants namely Alchornea floribunda, Annona muricata, Euphorbia prostata, Pachypodanthium staudtii and Passiflora edulis represent a source of anticancer drugs. Annona muricata and Passiflora edulis are good cytotoxic plants that could be exploited to develop phytomedicine to fight mostly hematological cancers including MDR phenotypes.

Modulation of intracellular expression of IFNγ and IL-2 in culture of splenic T lymphocytes by some flavonoid glycosides of Alchornea floribunda

Context Alchornea floribunda Müll. Arg. (Euphorbiaceae) leaves are widely used in ethnomedicine for the management of rheumatism, arthritis and toothache.Objective In this study, flavonoid glycosides isolated from Alchornea floribunda were screened for their effect on the intracellular expression of interferon-gamma (IFNγ) and interleukin-2 (IL-2) type-1 cytokines.Materials and methods Chromatographic purification of the ethyl acetate fraction of the methanol leaf extract led to the isolation of seven flavonoid glycosides (1–7). Their structures were elucidated by 1D and 2D nuclear magnetic resonance and mass spectrometry. Splenocytes were treated with graded concentrations of the compounds (6.25–25 μg/mL) and incubated for 24 h. Thereafter, their effect on the expression of IFNγ and IL-2 by CD4+ and CD8+ T-lymphocytes was evaluated using intracellular cytokine staining and FACS analysis.Results Compounds 1–7 (6.25–25 μg/mL) caused the up-regulation of activated CD8+ (57.85–72.45% versus 57.85% for untreated control) and, to a lesser extent, activated CD4+ (3.21–7.21% versus 2.75% for the untreated control) T-lymphocytes that were both largely interferon-gamma-releasing in treated mouse T lymphocytes relative to untreated control. FACS data analysis showed that stimulation with all the compounds increased the proportion of CD8+/IFNγ+ and CD4+/IFNγ+ T lymphocytes up to two-fold when compared with the cells in untreated control wells. Intracellular IL-2 secretion by treated T cells was not detected.Conclusion This recorded T-lymphocyte-specific immune-modulatory property may contribute to explain in part the dynamics associated with the ethnomedicine of Alchornea floribunda, and may find relevance as a necessary cellular immune response precursor to infection-associated disease management.

Antibacterial activities of plants from Central Africa used traditionally by the Bakola pygmies for treating respiratory and tuberculosis-related symptoms

Ethnopharmacological relevanceThe antibacterial activities of 18 plants from 10 different families were investigated for their antimicrobial efficacy, based on the traditional uses of these species by Bakola pygmies living in Central Africa, especially along the Ngoyang area in Cameroon for the treatment of respiratory and tuberculosis-related symptoms. The aim of the study is to test the antimicrobial efficacy of these plants against some pathogens associated with respiratory disease and to determine if there is any validation for the traditional use against Mycobacterium species. Materials and methodsMedium polar extracts were prepared in MeOH/DCM (1:1, v/v) from the plant parts of each species used traditionally and were assayed against pathogens associated with respiratory tract ailments [Staphylococcus aureus (ATCC 25923), Klebsiella pneumoniae (ATCC 13883) and Morexella cattarhalis (ATCC 14468)] using the minimum inhibitory concentration (MIC) method. Two additional faster growing Mycobacterium strains [Mycobacterium smegmatis (ATCC 23246) and Mycobacterium aurum (NCTC 10437)] were included in the assay as predictive test organisms for the more pathogenic strain Mycobacterium tuberculosis. ResultsSome plant species, such as Alchornea floribunda, Musanga cecropioides (both leaves and stem bark), Tetracera potatoria and Xylopia aethiopica (stem bark), were effective in inhibiting Morexella cattarhalis, having MIC values between 65 and 250μg/mL. Some noteworthy antimycobacterial inhibition (MIC≤200μg/mL and as low as MIC 6.5µg/mL) for 54% of the extracts were observed. ConclusionWhile moderate activity was shown for pathogens causing respiratory tract infections, these plant species seems to be selectively targeting Mycobacteria spp. suggesting that the traditional use for treating tuberculosis related symptoms may be indeed be accurate.

Antibacterial activity of the roots, stems and leaves of Alchornea floribunda

Ethnopharmacological relevanceAlchornea floribunda Müll. Arg. is used in traditional medicine across Africa for the treatment of bacterial, fungal, parasitic and inflammatory disorders. Aim of the studyTo evaluate the antibacterial activity of the crude extracts of different plant parts in order to provide a scientific rationale for the proposed broad efficacy of Alchornea floribunda in the treatment of bacterial infections. Materials and methodsExtracts of roots, stems and leaves were prepared using solvents of various polarities in order to extract a wide range of phytochemicals. The antibacterial activity of these crude extracts was evaluated by micro-dilution assay, against Gram-positive (i.e. Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus and Staphylococcus saprophyticus) as well as Gram-negative (i.e. Escherichia coli, Klebsiella pneumoniae, Moraxella catarrhalis and Proteus mirabilis) bacteria. ResultsGenerally, the ethanol (EtOH), methanol (MeOH), ethyl acetate (EtOAc) and chloroform (CHCl3) extracts demonstrated the best activities, with the leaves exhibiting the highest average activity for six of the eight pathogens. Of these, the ethanolic leaf extract was the most active against Staphylococcus aureus with an MIC value of 50µg/mL. Some other notable activity was observed for the ethyl acetate and chloroform root extracts against Staphylococcus aureus (50µg/mL), and for selected stem extracts against Staphylococcus aureus (50µg/mL), Klebsiella pneumoniae (63µg/mL) and Staphylococcus saprophyticus (63µg/mL). ConclusionThis study demonstrates the promising antibacterial activity of Alchornea floribunda against both Gram-positive and Gram-negative bacteria responsible for gastrointestinal, skin, respiratory and urinary ailments, and validates its use in the ethnopharmacology of the region.

Antioxidant phenolic compounds from Alchornea floribunda leaves

Alchornea floribunda leaves have been previously shown to posses potent anti-inflammatory compounds1 – 3. Further chemical investigation of a flavonoid sub-fraction of the methanol leaf extract of Alchornea floribunda led to the isolation of three flavans (-) catechin (+) catechin (-) epicatechin and a flavanone (2R, 3R) dihydroquercitin. The structures of these compounds were elucidated by 1 D and 2 D NMR spectroscopy and Liquid Chromatography- Electrospray Ionization Mass Spectrometry (LC-ESIMS). All the isolated compounds were assessed for their anti-oxidant potential in vitro using DPPH free radical scavenging and Ferric reducing ability4. In the DPPH model, (-) epicatechin, (+) epicatechin and (2R, 3R) dihydroquercitin showed high free radical scavenging activity with IC50 values of 19, 40 and 46 µg/mL respectively with the activity of (-) epicathechin comparable to that of the standard, chlorogenic acid (IC50 = 22 µg/mL). (-) catechin showed only mild activity with IC50 value of 88 µg/mL. In the Ferric reducing test, (-) catechin, (-) epicatechin and (+) epicatechin exhibited IC50 values of 46, 68 and 88 22 µg/mL respectively with the activity of (-) epicathechin higher than that of the standar, ascobic acid (IC50 = 66 µg/mL). (2R, 3R) dihydroquercitin showed poor Ferric reducing activity (IC50 > 100 µg/mL). The observed antioxidant activities of the isolated flavans may explain the efficacy of the extract of Alchornea floribunda leaves in the ethnomedicinal management of diseases associated with oxidative stress.

Plant selection for nest building by western lowland gorillas in Cameroon

We examined 834 nests built by western lowland gorillas in Cameroon between July 2008 and July 2011 to identify the plant species used in their construction. Preference for each plant species for nesting was assessed using a 'preference index' calculated by combining information on the occurrence of each species in the forest and in the nests. Forty-six plant species representing about 15 % of the total number of species in the forest and 26 % of species used for nest building were frequently used by gorillas. Preference levels significantly varied among these species. Nests were mostly built with herbs of the families Marantaceae and Zingiberaceae and woody species such as Manniophyton fulvum (liana) and Alchornea floribunda (shrub). As observed in other gorilla populations, suitability for nest building and availability of gorilla food in stems were the likely determinants of plant selection. The total number of species used per nest ranged from 1 to 11, with an average of 4.9. This is high compared to other sites, emphasizing variability in the availability of nest building materials and habitat differences across the range of the western gorilla. Seasonal changes in the use of different habitat types for nesting did not appear to influence plant use for nest building as there was little variation in plant selection across seasons or the composition of nests. Our findings suggest that gorillas non-randomly select plant species to build nests, and use a particular set of species combined at varying proportions, with no clear seasonal or spatial patterns.

Topical anti-inflammatory constituents of lipophilic leaf fractions of Alchornea floribunda and Alchornea cordifolia

The leaves of Alchornea floribunda and Alchornea cordifolia are used traditionally as topical anti-inflammatory agents. In this study, two highly lipophilic fractions AFLF and ACLF isolated from A. floribunda and A. cordifolia leaves respectively were investigated for topical anti-inflammatory effects using xylene-induced mice ear oedema as a model of inflammation. AFLF and ACLF at 5 mg per ear showed significant (p < 0.01) topical anti-inflammatory effect with oedema inhibitions of 64.0% and 79.0% at 2 h, respectively. When compared to indomethacin (5 mg per ear), these fractions showed significantly (p < 0.05) higher topical anti-inflammatory effect. Gas chromatography–mass spectrometry analysis revealed that AFLF is composed mainly of long chain saturated and unsaturated hydrocarbons (18.78%) and their oxygenated derivatives (1.89%); while ACLF is rich in volatile oils eugenol (21.26%) and cadinol (4.76%), and other constituents like, nanocosaine (36.86%) and steroid derivatives, ethyl iso-allocholate (4.59%) and 3-acetoxy-7,8-epoxylanostan-1-ol (15.86%). Analysis of the volatile oil (ACV) extracted from the fresh leaves of A. cordifolia revealed the presence of high concentrations of eugenol (41.7%), cadinol (2.46%), Caryophylene (1.04%), Linalool (30.59%) and (E)-α-bergamotene (4.54%). These compounds could be contributing to the topical anti-inflammatory effects of A. floribunda and A. cordifolia leaf extracts.

A new anti-inflammatory flavonol glycoside from Alchornea floribunda leaves

Alchornea floribunda leaves are widely used in African ethnomedicine for the management of acute and chronic inflammatory disorders. In the present study, bioactivity-guided fractionation of the ethyl acetate fraction of the methanol leaf extract of the plant material led to the isolation of a new flavonol glycoside (AFF1). The anti-inflammatory activity of this novel compound was evaluated using egg albumen-induced rat paw oedema as a model of inflammation. AFF1 showed significant inhibition of the rat paw oedema in a dose-dependent manner. The activity of AFF1 (50 mg kg−1) was higher than that of the standard anti-inflammatory drug, aspirin (100 mg kg−1). The compound also significantly (p < 0.001) inhibited heat-induced haemolysis of human erythrocytes in vitro. The structure of AFF1 was elucidated as 3,5,7,3′-tetrahydroxyflavone-3-O-α-L-rhamnoside, using a combination of UV, IR, 1D and 2D (COSY) 1H-NMR spectroscopy. This compound, in part, accounts for the anti-inflammatory effect of A. floribunda leaves.

Preliminary anti-microbial and phytochemical investigation of the extracts and column fractions of &lt;i&gt;Alchornea Floribunda&lt;/i&gt; leaves

The leaves of Alchornea floribunda were collected, identified and reduced to coarse powder. Using various solvent treatments, the powdered drug leaf was fractionated into A1, A2, B, C and D. The fractions were subjected to anti-microbial screening and phytochemical analysis. Phytochemical analysis of the extracts showed the presence of terpenes, sterols, flavonoids, tannins, carbohydrate, glycoside, saponins and alkaloids. Only fraction A2 (the terpenoid fraction) showed promising antimicrobial activity against Pseudomonas aeruginosa (IZD 42 mm) Salmonella keitambii (IZD 34mm) and Bacillus subtilis (IZD 32mm). A2 was further separated into 14 major column chromatographic fractions. The fractions were subjected toanti-microbial and phytochemical investigation. Fraction Af7, Af9, Af12 and Af13 (all terpenoids) showed mild activity against Pseudomonas aeruginosa and Salmonella keitambii. In conclusion, the anti-microbial activity of Alchornea floribunda leaves can be attributed to the presence of the terpenoids which may interact synergistically to causeinhibition of the sensitive bacteria.

Anti-inflammatory and Membrane-stabilizing Stigmastane Steroids fromAlchornea floribundaLeaves

Alchornea floribunda (Euphorbiaceae) leaves are widely used in African ethnomedicine for the management of acute and chronic inflammatory disorders. In the present study, bioactivity-guided fractionation led to the isolation of two known (1 and 3) and one new (2) stigmastane steroids from the hexane extract of Alchornea floribunda leaves. The anti-inflammatory activities of these compounds were evaluated using IN VITRO and IN VIVO animal models. The compounds 1, 2, and 3 at 50 and 100 microg/ear significantly (p < 0.05) inhibited xylene-induced ear edema in mice in a dose-dependent manner. The topical anti-inflammatory effect of 1 and 2 are significantly (p < 0.05) higher than that of indomethacin and prednisolone. At 20 mg/kg (i. p.), all the compounds significantly (p < 0.05) inhibited acute inflammation induced by subplantar injection of egg albumen in rats. Compound 1 exhibited an anti-inflammatory effect (50.9 % edema inhibition) comparable (p < 0.05) to that of prednisolone (48.0 % edema inhibition) at 3 h. Compounds 1, 2, and 3 (50 microg/mL) significantly (p < 0.05) inhibited heat-induced haemolysis of human erythrocytes in vitro, but had no effect on hypotonicity-induced hemolysis. The compounds were elucidated as (24R)-5alpha-stigmast-3,6-dione ( 1), 5alpha-stigmast - 23-ene-3,6-dione ( 2), and 3beta-hydroxy-5alpha-stigmast-24-ene ( 3) by spectral analysis. The results of this study show that these compounds may, in part, account for the anti-inflammatory effect of Alchornea floribunda leaves. This is the first report on the isolation and structure elucidation of these anti-inflammatory steroids from Alchornea floribunda leaves.

Topical anti-inflammatory effect of lipophilic constituents from Alchornea floribunda and Alchornea cordifolia leaves

The leaves of Alchornea floribunda and Alchornea cordifolia are used traditionally as topical anti-inflammatory agents. Several studies have shown that the hexane extracts of the plant materials exhibited significant anti-inflammatory activity [1,2,3]. In the present study, we subjected the hexane extracts of Alchornea floribunda and Alchornea cordifolia leaves to column chromatographic separation and isolated two highly lipophilic fractions AFLF and ACLF respectively. The anti-inflammatory effects of these fractions were investigated using xylene – induced oedema as a model of inflammation. AFLF and ACLF at 5mg/ear showed significant (P&lt;0.001) topical anti-inflammatory effect with oedema inhibitions of 64.0 and 79.0% at 2h respectively. These fractions showed significantly higher topical anti-inflammatory effect than 5mg/ear indomethacin (oedema inhibition of 48% at 2h). GC/MS analysis of these fractions revealed that AFLF is composed mainly of long chain saturated and unsaturated hydrocarbons (18.78%) and their oxygenated derivatives (1.89%), long chain carboxylic (fatty) acids (2.72%) and their esters (5.53%); while ACFL is rich in volatile oils euginol (21.26%) and cadinol (4.76%) and other constituents like long chain primary alcohols (4.78%), long chain saturated hydrocarbon, nanocosane (36.86) and steroid derivatives, ethyl iso-allocholate (4.59%) and 3-acetoxy-7,8-epoxylanostan-1-ol (15.86%). These constituents are highly lipophilic and can easily permeate lipoidal layers of skin. They may contribute significantly to the observed topical anti-inflammatory effect of Alchornea floribunda and Alchornea cordifolia leaf extracts.

Three anti-inflammatory stigmastane steroids from Alchornea floribunda leaves

The anti-inflammatory activity of Alchornea cordifolia has been reported in previous studies [1,2,3]. In the present study, bioactivity – guided fractionation led to the isolation of three stigmastane steroids from Alchornea floribunda leaves. The anti-inflammatory activities of these compounds were evaluated using in vitro and in vivo animal models. The compounds, 1, 2 and 3 at 5mg/ear inhibited xylene – induced ear edema in mice, with edema inhibitions of 59.9, 51.5 and 51.54% respectively. At 20mg/kg (ip), all the compounds significantly (p&lt;0.05) inhibited acute inflammation induced by subplanta injection of undiluted egg albumen in rats' paw. Compound 1 exhibited a higher anti-inflammatory effect (% edema inhibition=50. 0) than prednisolone (% edema inhibition=48.0) at 3h. 1 and 3 at concentrations of 50 and 100µg/ml significantly (p&lt;0.05) stabilized heat-induced haemolysis of human erythrocytes in vitro, but have no effect on hypotonicity-induced haemolysis. Spectral analysis elucidated the compounds as stigmastane –3, 6– dione (1), stigmastane –22– ene –3, 6– dione (2) and 3– hydroxystigmastane –22– ene (3). These compounds may, in part, account for the anti-inflammatory effect of Alchornea floribunda leaves. This is the first report on the isolation and structure elucidation of anti-inflammatory steroids from Alchornea floribunda leaves.

Some ethnopharmacological notes on African hallucinogens

This paper provides a short overview of ritual African hallucinogens. In addition to examples already listed by Schultes and Hofmann in their classic text books, Boophane disticha, Alchornea floribunda, Monadenium lugardae, Mostuea spp. and Voacanga bracteata are identified as African botanicals with proven or alleged hallucinogenic potential.