Quantification of polyphenols and flavonoid content and evaluation of anti-inflammatory and antimicrobial activities of Stenocereus stellatus extracts.

The hexanic, ethyl acetate and methanolic extracts from branches of Stenocereus stellatus were tested in both the 12-O-tetradecanoylphorbol-13-acetate (TPA) - induced ear oedema model and antimicrobial activity assay. The % of oedema inhibition, the Minimum Inhibitory Concentration (MIC), as well as the polyphenolic and flavonoid content were determined. Also, extracts were analysed by gas chromatography-mass spectrometry (GC-MS). In TPA model, the three extracts showed moderate oedema inhibition. In the antimicrobial activity assay, methanolic extract shows better MIC against all strains. The lowest MICs were for Candida albicans (31 µg/mL) and Rhizopus sp. (15 µg/mL). Also, 50.78 mg eq. of gallic acid/g extract of polyphenol and 115.12 mg eq. of catequine/g extract of flavonoids content were founded in ethyl acetate extract. In the chromatographic analysis, ß-sitosterol, ß-amyrine, betulin and some other molecules were identified. The results show that S. stellatus possess antimicrobial activities against some fungus species.

Anti-ulcer activity of Cyrtocarpa procera analogous to that of Amphipterygium adstringens, both assayed on the experimental gastric injury in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: The bark of Amphipterygium adstringens (Aa) is commonly mixed or adulterated with the bark of Cyrtocarpa procera (Cp) and sold in Mexican markets. Aa is a well known species in Mexico used as decoction to relieve ulcers. Scientific reports reinforcing the anti-ulcer activity of Aa have been previously described, but those describing the anti-ulcer properties of Cp as a substitute for Aa in folk medicine are scarce. AIM OF THE STUDY: To investigate anatomical and phytochemical differences between these species, as well as to assess the anti-ulcer effect of Cp extracts in comparison to the Aa extracts. MATERIAL AND METHODS: Anatomical micro-technique and physical and spectroscopic data were used to analyze differences between Cp and Aa. Regard to the pharmacological activity, it was assessed by using the ethanol-induced gastric damage model in rats. RESULTS: Whereas the bark anatomy of Aa was characterized by vertical canals in the periderm and the rare occurrence of fibers in its phloem, a periderm without vertical canals and abundant fibers in the phloem were distinctive features of Cp. Phytochemical analysis allowed the identification of tirucallane, masticadienonic and 3α-hydroxymasticadienonic acids as major components in Aa, while ß-amyrin and ß-sitosterol were obtained from Cp. Gastric lesions observed in the control group decreased in the presence of 100mg/kg of hexane, ethyl acetate and methanol extracts from the normal or regenerated bark of Cp, thus resembling the anti-ulcer effect of Aa. Nevertheless, major anti-ulcer potency was observed with the most active methanol extract from Cp obtained from normal [the effective dose fifty ED(50)=45.54 mg/kg] or regenerated (ED(50)=36.68 mg/kg) bark in comparison to Aa (ED(50)=115.64 mg/kg). CONCLUSION: Chemical and anatomical differences were found between these species, but since the anti-ulcer activity of Cp is similar to that shown by Aa our results reinforce the use of both species for the relief of gastric ulcer in folk medicine.

Bioactivity-guided isolation of beta-sitosterol and some fatty acids as active compounds in the anxiolytic and sedative effects of Tilia americana var. mexicana.

Tilia species have been used as anxiolytics for many years. In a previous study anxiolytic-like effects of a hexane extract of Tilia americana var. mexicana inflorescences were observed in experimental models in mice. To get additional insights into the neuroactive actions of this particular Tilia species, in this study we report a bioactivity guided-fractionation of the extract and separation by column chromatographic methods to isolate three fatty acids and a triterpene identified as beta-sitosterol as major constituents. Our results revealed that the crude extract at 10 and 30 mg/kg I. P. and some pooled fractions at the same dosages potentiated sodium pentobarbital-induced sleeping time and caused a significant increase in the time spent at the open-arm sides in the plus-maze test. A reduction in the exploratory behavioral pattern manifested as ambulatory activity, as well as head dipping and rearing tests was also observed. Further fractionation and purification yielded four major fractions containing fatty acids and beta-sitosterol as the active compounds. A dose-response curve of beta-sitosterol in the range 1 to 30 mg/kg doses indicated that this compound produced an anxiolytic-like action from 1 to 10 mg/kg and a sedative response when the dose was increased to 30 mg/kg, these effects resemble those produced by diazepam (0.1 mg/kg). Our results suggest that hexane extract of Tilia americana var. mexicana produces depressant actions on the central nervous system, at least in part, because of the presence of beta-sitosterol and some fatty acids that remain to be identified.