Arboreasides A-E, triterpene saponins from the bark of Cussonia arborea

Evaluation of Antimalarial Activity of Ethanolic Extract of Annona muricata L.: An in vivo and an in silico Approach

In Nigeria, Annona muricata L. has been used to treat a variety of ailments. The mechanism of the antimalarial activity of ethanolic leaf extract of Annona muricata (EEAML) was investigated using both an in vivo and an in silico approach. The experimental mice were divided into five groups: A-F. The mice in groups B-F were inoculated with Plasmodium berghei NK-65 and treated accordingly. Groups A and B are the negative and positive controls (infected and untreated), respectively. Group C received 10 mg/kg chloroquine (standard drug), whereas groups D-F received 100, 200, and 300 mg/kg body weight of the extract orally respectively. The mice were euthanized eight days after infection, and their liver and blood were collected and used in biochemical tests. Molecular docking was performed using the extract's HPLC compounds and Plasmodium falciparum proteins. In the suppressive, prophylactic, and curative tests, there was a significant decrease (p < 0.05) in parasitemia levels in groups treated with the extract compared to the positive control and standard drug. When compared to the positive control, there was a significant (p < 0.05) reduction in liver MDA, total cholesterol, and total triglyceride levels. The binding energies of luteolin and apigenin-pfprotein complexes were significantly (p < 0.05) higher compared to their respective references. The anti-plasmodial activity of the extract may result from its hypolipidemic effect, which deprives the parasite of essential lipid molecules needed for parasite growth, as well as from the inhibitory effects of apigenin and luteolin on specific proteins required for the Plasmodium metabolic pathway.

Manniosides B-F, five new triterpenoid saponins from the leaves of Schefflera mannii (Hook.f.) Harms

Fifteen triterpenoid saponins including five new compounds (Mannioside B: 3β-[(β-d-glucopyranosyl)oxy]urs-12-en-28-oic acid α-l-rhamnopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl ester (1), mannioside C: 3β-[(β-d-glucopyranosyl)23-dioxy]urs-12-en-28-oic acid α-l-rhamnopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl ester (2), mannioside D: 3β,23-dihydroxyurs-12-en-28-oic acid β-d-glucopyranosyl-(1 → 6)- β-d-glucopyranosyl ester (3), mannioside E: 3β-hydroxy-23-oxolup-20(29)-en-28-oic acid α-l-rhamnopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl ester (4) and mannioside F: (22S)-27β-[(β-d-glucopyranosyl)oxy]-22-hydroxyprotosta-12,24-dien-3β-yl β-d-glucopyranoside (5)) were isolated from the leaves of Schefflera mannii (Hook.f.) Harms. Their structures were established on the basis of 1D and 2D NMR data, mass spectrometry and chemical methods. The major isolated compounds were tested for their antiproliferative activity on human malignant epithelial (HeLa) cells but were not efficient at the concentration of 33 mM.

Immunomodulatory activities of isolated compounds from the root-bark of Cussonia arborea

CONTEXT

Cussonia arborea Hochst. ex A. Rich (Araliaceae) is a folk medicine used to treat various diseases. However, there is no report of the root phytochemistry.

OBJECTIVE

This study isolates and identifies the immunomodulatory compounds from root-bark of C. arborea.

MATERIALS AND METHODS

The methanol extract (18 g) was subjected to repeated column chromatography resulting in isolation of five compounds (1-5). Structure determination was achieved by analysis of their 1 D and 2 D NMR, and mass spectroscopy. The compounds (100-1.0 μg/mL) were examined immunomodulatory for effect on production of reactive oxygen species (ROS) from whole blood phagocytes and on proliferation of T-cells. The compounds cytotoxicity (100-1.0 μg/mL) was evaluated on NIH-3T3 normal fibroblast cells.

RESULTS

Three pentacyclic triterpenoids [3, 23-dihydroxy-12-oleanen-28-oic acid (1), 3β-hydroxylolean-12-en-28-oic (2) and 23-hydoxy-oxo-urs-12-en-28-oic acid (5)], two phytosterols: [stigmasterol (3)] and [3-O-β-d-glucopyranosyl stigmasterol (4)] were all isolated from the methanol soluble extract. All the tested compounds (1-4) were found to be nontoxic on NIH-3T3 cells. Compound 1 and 2 moderately inhibited the production of ROS (IC₅₀ = 24.4 ± 4.3 and 37.5 ± 0.1 μg/mL, respectively) whereas compound 2 exhibited the highest inhibitory effect (IC₅₀ = 12.6 ± 0.4 μg/mL) on proliferation of phytoheamagglutinin (PHA) activated T-cells.

CONCLUSIONS

The isolated compounds (1-5) are reported for the first time from this species. In addition, compound 2 with suppressive potential on production of intracellular ROS and proliferation of T-cells could be of immense value in control of autoimmune diseases as well as in immune compromised patients.

Triterpenoids

This review covers the isolation and structure determination of triterpenoids, including squalene derivatives, protostanes, lanostanes, holostanes, cycloartanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, serratanes and saponins; 278 references are cited.

Steroidal saponins from two species of Dracaena

Four new steroidal saponins (1-4) were isolated from the stem and bark of two species of Dracaena: deistelianosides A and B (1 and 2) from D. deisteliana and arboreasaponins A and B (3 and 4) from D. arborea. Six known saponins and one known sapogenin were also isolated. The structures of 1-4 were established as diosgenin 3-O-[3-O-sulfate-alpha-l-rhamnopyranosyl-(1-->4)]-beta-d-glucopyranoside (1), 1-O-beta-d-xylopyranosyl-(1-->2)-[alpha-l-rhamnopyranosyl-(1-->3)]-beta-d-fucopyranosyl(23S,24S)-spirosta-5,25(27)-diene-1beta,3beta,23alpha,24alpha-tetrol 24-O-alpha-l-arabinopyranoside (2), pennogenin-3-O-alpha-l-rhamnopyranosyl-(1-->2)-[alpha-l-rhamnopyranosyl-(1-->3)]-[6-O-acetyl]-beta-d-glucopyranoside (3), and 24alpha-hydroxypennogenin 3-O-alpha-l-rhamnopyranosyl-(1-->2)-[alpha-l-rhamnopyranosyl-(1-->3)]-beta-d-glucopyranoside (4) using extensive 1D and 2D NMR spectroscopic analyses and mass spectrometry. Cytotoxic activity of several of these compounds was evaluated against the HT-29 and HCT 116 human colon cancer cell lines.

Antimicrobial and antimalarial activity of Cussonia species (Araliaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

Cussonia species are used in African traditional medicine mainly against pain, inflammation, gastro-intestinal problems, malaria and sexually transmitted diseases.

AIM OF THE STUDY

To summarise ethnomedicinal uses of Cussonia and to find scientific evidence in support of selected main uses.

MATERIALS AND METHODS

Using the minimum inhibitory concentration (MIC) method, leaves of 13 Cussonia species, Schefflera umbellifera and Seemannaralia gerrardii were tested against pathogens associated with diarrhoea (Enterococcus faecalis and Escherichia coli), sexually transmitted infections (Neisseria gonorrhoeae and Trichomonas vaginalis) and general infectious diseases (Staphylococcus aureus and Pseudomonas aeruginosa). Antimalarial sensitivity was studied using Plasmodium falciparum and the [(3)H]-hypoxanthine incorporation assay. Cytotoxic effects on a T-cell leukaemia (Jurkat) cell line were determined using the tetrazolium-based cellular toxicity assay.

RESULTS

Methanolic extracts were active against Pseudomonas aeruginosa (MIC of 1.0-1.5 mg/mL), Trichomonas vaginalis (MIC of 0.8-1.3 mg/mL) and Staphylococcus aureus (Cussonia arborea, 1.8 mg/mL). All samples were active against Neisseria gonorrhoeae (MIC of 0.02-0.7 mg/mL). The methanol extract of Cussonia arborea was the most active against Plasmodium falciparum (13.68 microg/mL) and showed anticancer properties (5.60 microg/mL).

CONCLUSIONS

The traditional use of Cussonia species to treat sexually transmitted diseases and Plasmodium infections appears to have a scientific basis.