Isolation of (-)(2S)-5,6,7,3',5'-pentahydroxyflavanone-7-O-ß-D-glucopyranoside, from Lippia graveolens H.B.K. var. berlandieri Schauer, a new anti-inflammatory and cytotoxic flavanone.

A new flavanone glycoside, (-)(2S)-5,6,7,3',5'-pentahydroxyflavanone-7-O-ß-D-glucopyranoside (1), was isolated from the stems of Lippia graveolens H.B.K. (Verbenaceae). The structure of 1 was elucidated based on spectral analysis and chemical transformations. The treatment of 1 with acetic anhydride and pyridine afforded the corresponding per-acetylated derivative 2, while an acid hydrolysis reaction of 1 afforded a 5,6,7,3',5'-pentahydroxy flavanone (3). Additionally, the anti-inflammatory and cytotoxic activities of 1, 2 and 3 were determined.

Pharmacological evaluation of the anxiolytic and sedative effects of Tilia americana L. var. mexicana in mice.

The anxiolytic and sedative effects of Tilia americana L. var. mexicana (Schltdl.) Hardin inflorescence extracts and its acute toxicity were tested. Sodium pentobarbital (SP)-induced hypnosis potentiation (SPP), as well as ambulatory activity and anti-anxiety response in three different experimental models were evaluated with hexane and methanol extracts in mice. In order to determine the proper timing of assessments and to identify the most active extract, a 100mg/kg dosage of hexane, ethyl acetate and methanol crude extracts were tested on SPP after 15, 30 and 60min of the administration. Then a dose-response curve was made for the hexane (10-1000mg/kg) and methanol (10-300mg/kg) extracts in all experimental models. Both extracts produced a significant and dose-dependent lengthening in the time of SP, with the methanol extract being more potent than the hexane extract at 60min after administration. Moreover, a significant and dose-dependent attenuation in the anxiety-response in the plus-maze test and exploratory cylinder activity, but also a diminution in the ambulatory activity and in the head dipping response were observed resembling the response to diazepam. Acute toxicity was observed with less dose of methanol extract (LD(50)=375mg/kg) in comparison to the hexane extract (LD(50)>2900mg/kg). Results of the present study shows that Tilia americana var. mexicana possesses depressant activity on the CNS similar to the better-studied species of European Tilia and reinforces its use as anxiolytic and sedative in traditional medicine.

High-performance liquid chromatography-mass spectrometric analysis of alkaloids extracted from seeds of Erythrina herbacea.

A sensitive, reverse-phase HPLC-MS method for the analysis of the alkaloids of Erythrina has been developed. The method is based on the use small amounts of crude extracts (20 mg) and is sufficiently sensitive to detect the presence of the typical alkaloids, such as erysodine, erysovine, erythraline, erysopine and the hexoside of erysopine, that are representative of the title species.

Principles of the bark of Amphipterygium adstringens (Julianaceae) with anti-inflammatory activity.

Despite the fact that Amphipterygium adstringens (usually known as "cuachalalate") is used intensively in traditional medicine throughout México, there are, to our knowledge, no previous studies concerning the actual therapeutic, anti-inflammatory properties of this species. This lack of data prompted us to evaluate the aqueous (AE) and hexane (HE) extracts from A. adstringens in two models of acute inflammation: 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema and carrageenan-induced paw edema. The results showed that HE possesses dose-dependent activity, while AE showed no anti-inflammatory effect on TPA-induced edema. Reverse effects were found in the carrageenan test, wherein AE showed a 73.5% of inhibition of edema, while HE showed only a 14.4% activity at 100 mg/kg body weight. These results could indicate that AE and HE possess different anti-inflammatory mechanisms of action. On the other hand, it is known that masticadienonic (1) and 3alpha-hydroxymasticadienonic (2) acids are the main constituents of the organic extract of A. adstringens bark. Because of this knowledge, we tested 1 and 2 in the same experimental models. The results showed that 2 possesses a dose-dependent effect, while 1 does not show a dose-dependent response in TPA-induced edema. In carrageenan-induced edema tests, both 1 and 2 showed almost the same activity (approximately 44% inhibition at 100 mg/kg body weight). In order to determine whether the anti-inflammatory activities of AE, HE, 1 and 2 are involved in the alteration of inducible nitric oxide synthase (iNOS) activity, we evaluated these substances by examining nitric oxide generation in lipopolysaccharide (LPS)-activated peritoneal macrophages. The results showed that 1 presented the highest activity (93.3%), followed by 2 (86.5%), while AE (57%) and HE (33.6%) showed the lowest. In the cytotoxic MTT assay, however only 1 and 2 showed any activity whatsoever.

[Monoclonal antibodies to dengue virus 4: the spectrum of the reactivity to 4 serotypes of dengue]. / Anticuerpos monoclonales al virus dengue 4: espectro de reactividad a los 4 serotipos del dengue.

These types of monoclonal antibodies 8E8, 3F7 and 1E9 to dengue 4 virus H-241 strain. These monoclonal antibodies show various patterns of reactivity to the four dengue serotypes and different antigen preparations of serotype 4 when they were tested in various serological methods. The monoclonal antibody 8E8 exhibited a specificity of serotype (D-2; by hemagglutination inhibition); subcomplex (D-2 and D-4 by immunofluorescence) and complex (by immunoperoxidase technique). It was able to neutralize by 80% homologous virus and it turned out to be the only reactive monoclonal antibody in the complement fixation test. The monoclonal 3F7 did not react to by hemagglutination inhibition, recognized serotypes D-1, D-2, D-3 and D-4 by immunofluorescence and only serotypes D1 and D4 by immunoperoxidase technique but it was unable to neutralize the homologous virus. The 1E9 antibody was reactive to serotypes D1, D-2, D-3 and D-4 only by hemagglutination inhibition and neutralized serotype D-4. All the monoclonal antibodies were able to react to various dengue antigens through an ELISA of double antibody and showed fluorescent activity against 38th pass in Beagle dog kidney culture; however, they could not react to a D-4 recombinant antigen.

Effect of crude extracts of Erythrina americana Mill. on aggressive behavior in rats.

Three alkaloid fractions were obtained from seeds of Erythrina americana: free alkaloids in hexane, free alkaloids in methanol and liberated alkaloids. The pharmacological evaluation of these fractions on rats showed that, administered in a dose of 3 mg/kg, the three fractions diminished the aggressive behavior. This is comparable when diazepam is used as a control. An interaction between the cholinergic and GABAergic system could be suggested.

Phytochemical study of cuachalalate (Amphiptherygium adstringens, Schiede ex Schlecht).

Cuachalalate is an endemic plant of Mexico and belongs to the Julianiaceae family. It is a resinous and dioecious plant and is a medicinal plant commonly used in Mexico. Its curative properties are: cholesterol lowering, anti-inflammatory, antiulcerous agent. The collection site is in Barranca Honda, Morelos, Mexico. Three samplings were made during the research period. A decortication of four trees per sex was carried out. An additional collection of resin was made during the last sampling, in order to verify the presence of the compounds of interest. Masticadienonic, alpha-hydroxymasticadienonic and masticadienonic/isomasticadienonic acid mixtures were isolated and identified. Major accumulations of masticadienonic, alpha-hydroxymasticadienonic acids and masticadienonic/isomasticadienonic acid mixtures were related to female plants and a mixture of alpha-hydroxymasticadienonic acid and an unknown compound with male plants. Major accumulation of masticadienonic acid occurred in February, and alpha-hydroxymasticadienonic was mainly found in November. An anti-inflammatory test with the alpha-hydroxymasticadienonic acid was made and strong inhibition of the inflammation was observed in a preliminary test.

Erythrina alkaloids: isolation and characterisation of alkaloids from seven erythrina species.

The alkaloids present in the seeds of seven ERYTHRINA species, E. FUSCA Lour, E. COSTARICENCIS M. Micheli, E. LEPTORHIZA A. DC., E. SPECIOSA Andrews, E. VARIEGATA L., E.MELANACANTHA Taubert ex Harms, and E. BERTEROANA Urban, have been screened by gas chromatography-mass spectrometry (GC/MS). The novel alkaloid erythrartine N-oxide has been isolated from E. BERTEROANA and characterized as an N-oxide of theknown alkaloid, erythrartine.