Medicinal foodstuffs. XXVII. Saponin constituents of gotu kola (2): structures of new ursane- and oleanane-type triterpene oligoglycosides, centellasaponins B, C, and D, from Centella asiatica cultivated in Sri Lanka.
Ursane- and oleanane-type triterpene oligoglycosides, centellasaponins B, C, and D, were isolated from the aerial parts of Centella asiatica (L.) Urban cultivated in Sri Lanka together with madecassoside, asiaticoside, asiaticoside B, and sceffoleoside A. The chemical structures of centellasaponins B, C, and D were determined on the basis of chemical and physicochemical evidence to be madecassic acid 28-O-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside, madasiatic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyra noside, and 3beta,6beta,23-trihydroxyolean-12-en-28-oic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyra noside, respectively. (+info)
Antiproliferative constituents from Umbelliferae plants VII. Active triterpenes and rosmarinic acid from Centella asiatica.
The antiproliferative constituents in the MeOH extract from the aerial parts of Centella asiatica were investigated. Activity-guided fractionation of MeOH extract resulted in the isolation of ursolic acid lactone, ursolic acid, pomolic acid, 2alpha,3alpha-dihydroxyurs-12-en-28-oic acid, 3-epimaslinic acid, asiatic acid, corosolic acid, and rosmarinic acid. Antiproliferative activity of the isolated compounds against human gastric adenocarcinoma (MK-1), human uterine carcinoma (HeLa), and murine melanoma (B16F10) cells was estimated. (+info)
Hepatotoxicity associated with the ingestion of Centella asiatica.
BACKGROUND: Hepatotoxicity due to herbal remedies is being increasingly recognized. Centella asiatica (Centella asiatica Linn Urban) is commercialized for multiple conditions. Its active principles are pentacyclic triterpenic saponosides (asiaticoside, madecassoside). CLINICAL CASE STUDIES: We present three women (61, 52 and 49 years old) who developed jaundice after taking Centella asiatica for 30, 20 and 60 days. Respective laboratory tests: ALT: 1193, 1694 and 324 U/L; ALP: 503, 472 and 484 U/L; bilirubin: 4.23, 19.89 and 3.9 mg/dl. The first patient also had ASMA 1/160 and AMA 1/320. Respective pathological diagnoses: granulomatous hepatitis with marked necrosis and apoptosis; chronic hepatitis with cirrhotic transformation and intense necroinflammatory activity, and granulomatous hepatitis. All patients improved with Centella asiatica discontinuation, and ursodeoxycholic acid 10 mg/kg/day. The first patient took Centella asiatica again, with recurrence of the damage. The second one had taken this herb a year before. CONCLUSIONS: Many plants synthesize hepatotoxic compounds. Germander, Skullcap and Glycyrrhizin contain di- or triterpenic active principles, which can produce hepatic injury by promoting apoptosis and altering cell membranes. We hypothesize that these mechanisms may have resulted in injuries associated with Centella asiatica. The presence of autoantibodies and granulomas also favors an immune-mediated mechanism. Ursodeoxycholic acid has anti-apoptotic properties, but we cannot rule out that Centella asiatica discontinuation alone may have resulted in patient improvement. (+info)
Cloning and expression of a farnesyl diphosphate synthase in Centella asiatica (L.) Urban.
A cDNA encoding farnesyl diphosphate synthase (FPS; EC220.127.116.11/EC18.104.22.168) was isolated from Centella asiacita (L.) Urban, using degenerate primers based on two highly conserved domains. A full-length cDNA clone was subsequently isolated by rapid amplification of cDNA ends (RACE) PCR. The sequence of the CaFPS (C. asiatica farnesyl diphosphate synthase) cDNA contains an open reading frame of 1029 nucleotides encoding 343 amino acids with a molecular mass of 39.6 kDa. The deduced CaFPS amino acid sequence exhibits 84, 79, and 72%, identity to the FPSs of Artemisia annua, Arabidopsis thaliana, and Oryza sativa, respectively. Southern blot analysis suggested that the C. asiatica genome contains only one FPS gene. An artificially expressed soluble form of the CaFPS was identified by SDS-PAGE. It had high specific activity and produced farnesyl diphosphate as the major isoprenoid. (+info)
Immunomodulatory activities of Centella asiatica and Rhinacanthus nasutus extracts.
Centella asiatica (CA) and Rhinacanthus nasutus (RN )have been used for treatment of various illnesses, but the mechanisms of action remain largely unknown. This study focused on the influence of CA and RN extracts on cell-mediated and humoral immune responses. In human peripheral blood mononuclear cells (PBMCs), CA (water extract) and RN (water and ethanol extracts) significantly increased proliferation and the production of IL-2 and TNF-alpha. In contrast, an ethanol extract of CA inhibited human PBMC mitogenesis and the production of IL-2 and TNF-alpha. BALB/c mice treated with CA extracts (100 mg/kg bw) showed higher responses to both primary and secondary antibodies against BSA when compared with non-treated group. Only the secondary antibody response was increased in RN extract-treated mice. The present study revealed immunomodulating activity of CA and RN extracts with regard to both non-specific cellular and humoral immune responses. The data available to date suggest that they may have chemopreventive or anticancer potential. (+info)
In vitro screening of five local medicinal plants for antibacterial activity using disc diffusion method.
Medicinal plants have many traditional claims including the treatment of ailments of infectious origin. In the evaluation of traditional claims, scientific research is important. The objective of the study was to determine the presence of antibacterial activity in the crude extracts of some of the commonly used medicinal plants in Malaysia, Andrographis paniculata, Vitex negundo, Morinda citrifolia, Piper sarmentosum, and Centella asiatica. In this preliminary investigation, the leaves were used and the crude extracts were subjected to screening against five strains of bacteria species, Methicillin Resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli, using standard protocol of Disc Diffusion Method (DDM). The antibacterial activities were assessed by the presence or absence of inhibition zones and MIC values. M. citrifolia, P. sarmentosum and C. asiatica methanol extract and A. paniculata (water extract) have potential antibacterial activities to both gram positive S. aureus and Methicillin Resistant S. aureus (MRSA). None of the five plant extracts tested showed antibacterial activities to gram negative E. coli and K. pneumoniae, except for A. paniculata and P. sarmentosum which showed activity towards P. aeruginosa. A. paniculata being the most potent at MIC of 2 g/disc. This finding forms a basis for further studies on screening of local medicinal plant extracts for antibacteria properties. (+info)
The anti-thrombotic active constituents from Centella asiatica.
The in vitro effects of a methanol extract from the aerial parts of Centella asiatica on shear-induced platelet activation and coagulation were assessed after oral administration to rats, by subjecting non-anticoagulated blood to haemostatometry. 3,5-Di-O-caffeoyl quinic acid, 1,5-di-O-caffeoyl quinic acid, 3,4-di-O-caffeoyl quinic acid, 4,5-di-O-caffeoyl quinic acid, and chlorogenic acid, together with asiaticoside, kaempferol, quercetine, kaempferol-3-O-beta-D-glucoside and quercetin-3-O-beta-D-glucoside were all isolated from the methanol extract. Amongst these, only 3,5-di-O-caffeoylquinic acid showed significant inhibition of shear-induced platelet activation and dynamic coagulation. The reactive curve of the inhibitory effect on the platelet reaction and the dynamic coagulation showed a bell-shape. (+info)
Dechlorophyllation by electrocoagulation.
Electrocoagulation was used for dechlorophyllation of alcoholic extracts from five plants. The results showed that for every plant extract studied, electrocoagulation was more efficient than the classical solvent extraction method in removing plant pigments, while not affecting the important secondary metabolites in those extracts. (+info)