Saponinas de ilex taubertiana

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Gastroprotective Mechanism and Ulcer Resolution Effect of Cyrtocarpa procera

Gastric ulcers are a worldwide health problem and their poor healing is one of the most important causes for their recurrence. We have previously reported the remarkable gastroprotective and anti-Helicobacter pylori activities of the methanolic extract (CpMet) of Cyrtocarpa procera bark. This work investigates, in a murine model, the CpMet gastroprotective mechanism and establishes its preclinical efficacy in the resolution of ethanol-induced gastric ulcers. The results showed that the gastroprotective activity of CpMet is mainly associated with endogenous NO and prostaglandins, followed by sulfhydryl groups and KATP channels. Furthermore, CpMet (300 mg/kg, twice a day) orally administered during 20 consecutive days promoted an ulcer area reduction of 62.65% at the 20th day of the treatment. The effect was confirmed macroscopically by the alleviation of gastric mucosal erosions and microscopically by an increase in mucin content and a reduction in the inflammatory infiltration at the site of the ulcer. No clinical symptoms or signs of toxicity were observed in the treated animals. The results indicate the safety and efficacy of CpMet in promoting high quality of ulcer healing by different mechanisms, but mostly through cytoprotective and anti-inflammatory effects, making it a promising phytodrug for ulcer treatment

Phytochemical screening, antioxidant activity and toxicity of the orchids Prosthechea cochleata and Prosthechea livida-A preliminary study

Phytochemical composition, antioxidant, and toxic effects of two orchid (Prosthechea cochleata and Prosthechea livida) were examined in their different hexane and dichloromethane/methanol extracts of leaves, pseudobulbs, rhizome and roots.  Phytochemical screening reveals the presence of alkaloids, coumarins, flavonoids, saponins, steroids and terpenes except for anthracene derivatives in P. livida and tannins in both species. Results showed exhibited significant toxicity against brine shrimp with an LC50 values ranged from 3 to 54 µg/ml in 24 h.  Finally, the results of the antioxidant test in yeast (Saccharomyces cerevisiae) showed that CH2Cl2:MeOH extract of P. cochleata root extract presented the most efficient protective antioxidant percentage (%PA), with 20 µg/mL, displaying a cell viability of 68.58%. In P. livida case, rhizome extract presented the most efficient %PA, with 1000 µg/mL, with a cell viability of 65.82%.  The results evidenced the toxicity of  Prosthechea cochleata and Prosthechea livida and reveals potential antioxidative of extracts

Cytotoxic activity and chemical composition of the root extract from the mexican species Linum scabrellum: mechanism of action of the active compound 6-Methoxypodophyllotoxin

12 p.-6 fig.-1 tab.The cytotoxic activity and the chemical composition of the dichloromethane/methanol root extract of Linum scabrellum Planchon (Linaceae) were analyzed. Using NMR spectra and mass spectrometry analyses of the extract we identified eight main constituents: oleic acid (1), octadecenoic acid (2), stigmasterol (3), α-amyrin (4), pinoresinol (5), 6 methoxypodophyllotoxin (6), coniferin (7), and 6-methoxypodophyllotoxin-7-O-β-D-glucopyranoside (8). By using the sulforhodamine B assay, an important cytotoxic activity against four human cancer cell lines, HF6 colon (IC50 = 0.57 μg/mL), MCF7 breast (IC50 = 0.56 μg/mL), PC3 prostate (IC50 = 1.60 μg/mL), and SiHa cervical (IC50 = 1.54 μg/mL), as well as toward the normal fibroblasts line HFS-30 IC50 = 1.02 μg/mL was demonstrated. Compound 6 (6-methoxypodophyllotoxin) was responsible for the cytotoxic activity exhibiting an IC50 value range of 0.0632 to 2.7433 µg/mL against the tested cell lines. Cell cycle studies with compound 6 exhibited a cell arrest in G2/M of the prostate PC3 cancer cell line. Microtubule disruption studies demonstrated that compound 6 inhibited the polymerization of tubulin through its binding to the colchicine site (binding constant K b = 7.6 × 10(6) M(-1)). A dose-response apoptotic effect was also observed. This work constitutes the first investigation reporting the chemical composition of L. scabrellum and the first study determining the mechanism of action of compound 6.Ivonne Alejandre-Garc´ıa acknowledges fellowship 226354 from CONACYT. The authors thank Dr. Alfonso Lejia from Centro de Ciencias Genomicas, UNAM, for technical ´assistance. The authors are indebted to Dr. T Fitzgerald from Florida A&M University for his kind gift of the colchicine analog 2-methoxy-5-(2,3,4-trimethoxyphenyl)-2,4,6-cycloheptatrien-1-one (MTC). Partial support from CONACYT (Grants CB 156276 and 222714) is acknowledged.The authors thank Laboratorio Nacional de Estructura de Macromoleculas (Conacyt 251613) for the spectroscopic and ´mass analyses and support given to J. F. D. from BIPPED2 and BIO2013-42984R from the Ministry of Economy of Spain.Peer reviewe

Saponinas de ilex pseudobuxus reissek

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Saponinas de ilex brevicuspis reissek

51

Saponinas de ilex pseudobuxus reissek

57

Determinação do amargor para diferentes espécies de ilex

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Determinação do amargor para diferentes espécies de ilex

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