Bioactive extracts of red seaweeds Pterocladiella capillacea and Osmundaria obtusiloba (Floridophyceae: Rhodophyta) with antioxidant and bacterial agglutination potential.

OBJECTIVE: To evaluate the antioxidant, antibacterial and bacterial cell agglutination activities of the hexane (Hex) and 70% ethanol (70% EtOH) extracts of two species of red seaweeds Pterocladiella capillacea (P. capillacea) and Osmundaria obtusiloba. METHODS: In vitro antioxidant activity was determined by DPPH radical scavenging assay, ferric-reducing antioxidant power assay, ferrous ion chelating assay, ß-carotene bleaching assay and total phenolic content quantification. Antimicrobial activity was tested using the method of disc diffusion on Mueller-Hinton medium. The ability of algal extracts to agglutinate bacterial cells was also tested. RESULTS: The 70% EtOH extract of the two algae showed the highest values of total phenolic content compared to the Hex extract. The results of DPPH for both extracts (Hex, 70% EtOH) of Osmundaria obtusiloba (43.46% and 99.47%) were higher than those of P. capillacea (33.04% and 40.81%) at a concentration of 1000 µg/mL. As for the ferrous ion chelating, there was an opposite behavior, extracts of P. capillacea had a higher activity. The extracts showed a low ferric-reducing antioxidant power, with optical density ranging from 0.054 to 0.180. Antioxidant activities of all extracts evaluated for ß-carotene bleaching were above 40%. There was no antibacterial activity against bacterial strains tested. However, the extracts of both species were able to agglutinate bacterial Gram positive cells of Staphylococcus aureus and Gram negative cells of Escherichia coli, multidrug-resistant Salmonella and Vibrio harveyi. CONCLUSIONS: This is the first report of the interaction between these algal extracts, rich in natural compounds with antioxidant potential, and Gram positive and Gram negative bacterial cells.

Anti-inflammatory and antinociceptive effects of hydroalcoholic extract from Pseudobombax marginatum inner bark from caatinga potiguar.

ETHNOPHARMACOLOGICAL RELEVANCE: The Pseudobombax marginatum (St Hil) Rob., Malvaceae, is mentioned in ethnobotanical studies. It is used as anti-inflammatory, for ulcers and gastritis, and back pain. To evaluate anti-inflammatory and antinociceptive activities a hydroalcoholic extract (HE) from inner bark was prepared. MATERIALS AND METHODS: For the anti-inflammatory activity, carrageenan-induced paw edema and peritonitis models, and also myeloperoxidase assay were used. For the antinociceptiva activity acetic acid-induced writhing, hot plate and formalin tests were employed. RESULTS: The HE extract exhibited an intense inhibition in carrageenan-induced edema model and also in myeloperoxidase activity at the doses of 100 and 300 mg/kg. The leukocyte migration into the peritoneal cavity was also inhibited at the doses of 30, 100 and 300 mg/kg. A similar profile was observed against acid-induced abdominal contortions and in formalin second phase test at the doses of 30 and 100 mg/kg, but this treatment did not affect the behavior of animals in the hot plate test. CONCLUSIONS: The experimental data of the HE from Pseudobombax marginatum show anti-inflammatory and antinociceptiva activities, confirming the indication from traditional medicine; however further studies are required to define and isolate the active anti-inflammatory and antinociceptiva components from this active specie.

1H and 13C NMR assignments for two new cordiaquinones from roots of Cordia leucocephala.

From the roots of Cordia leucocephala (Boraginaceae), two new meroterpenoid naphthoquinones, 6-[10-(12,12-dimethyl-13alpha-hydroxy-16-methenyl-cyclohexyl)ethyl]-1,4-naphthalenedione (cordiaquinone L) and 5-methyl-6-[10-(12,12-dimethyl-13beta-hydroxy-16-methenyl-cyclohexyl)methyl-1,4-naphthalenedione (cordiaquinone M) were isolated. Their structures were elucidated after detailed 1D and 2D NMR (COSY, HSQC, HMBC and NOESY) data analyses and comparison with literature data for analogous compounds.

Larvicidal and nematicidal activities of the leaf essential oil of Croton regelianus.

The chemical composition of the leaf essential oil of Croton regelianus collected from wild plants growing in two different sites at Ceará State (Brazil) was analyzed by GC/MS and GC-FID. Twenty monoterpenoids, representing more than 96% of the chemical composition of the oils, were identified and quantified. The oils showed similar chemical composition but considerable variation in the levels of each constituent. Ascaridole (33.9-17.0%), p-cymene (22.3-21.6%), and camphor (13.0-3.1%) were the predominant constituents. The monoterpene ascaridole was isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti and Artemia sp. larvae, and the root knot nematode Meloidogyne incognita. The bioassay results show that the essential oil of C. regelianus and ascaridole were moderately active against the M. incognita, but strongly effective against both A. aegypti and Artemia sp. larvae.

Avaliação do potencial fungicida de extratos etanólicos de Senna alata contra Monosparacus cannonballus / Evaluation of the fungicide potential of ethanolic extracts of Senna alata against Monosporascus cannonballus

Objetivou-se, neste trabalho, avaliar in vitro a atividade dos extratos alcoólicos de Senna alata (L.) Roxb. sobre Monosporascus cannonballus. O delineamento experimental foi inteiramente casualizado com esquema fatorial 3 x 6 + 1, sendo constituído por três partes da planta (caule, raiz e vagem), por seis concentrações (0,25; 0,50; 50; 75; 250; 500 ppm ) mais a testemunha, com quatro repetições por tratamento. As variáveis avaliadas foram: taxa de crescimento micelial (TCM), inibição do crescimento micelial (ICM) e área abaixo da curva do crescimento micelial (AACCM). A concentração de 500 ppm foi a mais eficiente, nas três partes vegetais avaliadas. O porcentual de inibição na referida concentração foi de 28,60 por cento, 36,70 por cento e 27,99 por cento para caule, raiz e vagem respectivamente. Diante dos resultados, observa-se que os extratos de S. alata indicam um forte potencial de controle para o fungo Monosporascus cannonballus.

The aim of this work was to evaluate the activity in vitro of the ethanolic extracts of Senna alata (L.) Roxb. over Monosporascus cannonballus. The experimental design was entirely randomized with factorial scheme 3 x 7 + 1, being constituted by three parts of the plant (root, stalk and green bean) for six different concentrations (0.25; 0.50, 50, 75, 250,500 ppm) plus the control, with four repeatitons for treatment. The available variables were: rate of micelial growth (TCM), inhibition of the growth micelial (ICM) and area under the curve of the growth micelial (AACCM). The concentration of 500 ppm was the most efficient ,in the three available vegetal parts. The percentual of inhibition in the concentration was of 28.60 percent, 36.70 percent e 27.99 percent for stalk, root and green bean respectively. Before of the results, the extracts of S. alata display high control potential for Monosporascus cannonballus fungi.

1H and 13C NMR spectral data of new saponins from Cordia piauhiensis.

Two new bidesmoside triterpenoid saponins were isolated from stems of Cordia piauhiensis. Their structures, characterized as 3-O-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl pomolic acid 28-O-beta-D-glucopyranosyl ester (1) and 3-O-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl ester (2), were unequivocally established after extensive NMR (1H, 13C, DEPT 135 degrees, COSY, HSQC, HMBC, TOCSY, and NOESY) studies.

Characterization of two minor saponins from Cordia piauhiensis by 1H and 13C NMR spectroscopy.

A careful NMR analysis with full assignment of the 1H and 13C spectral data for two minor saponins isolated from stems of Cordia piauhiensis is reported. These saponins were isolated by high-performance liquid chromatography and characterized as 3beta-O-[alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl]pomolic acid 28-O-[beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl] ester (1) and 3beta-O-[alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl]oleanolic acid 28-O-[beta-D-xylopyranosyl-(1 --> 2)-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranosyl] ester (2). Their structures were established using a combination of 1D and 2D (1H, 1H-COSY, TOCSY, NOESY, gs-HMQC and gs-HMBC) NMR techniques, electrospray ionization mass spectrometry and chemical evidence.

Complete 1H and 13C NMR assignments for two new monodesmoside saponins from Pentaclethra macroloba (Willd.) Kuntze.

A detailed NMR study and full assignments of the 1H and 13C spectral data for two novel triterpenoid saponins isolated from the stem bark of Pentaclethra macroloba (Willd.) Kuntze are described. Their structures were established using a combination of 1D and 2D NMR techniques including 1H,1H-COSY, TOCSY, NOESY, gs-HMQC and gs-HMBC, and also electrospray ionization mass spectrometry and chemical methods. The structures were established as 3beta-O-([O-beta-D-glucopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)]-[O-beta-D-glucopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)])-alpha-L-arabinopyranosylhederagenin (1) and 3beta-O-)[O-beta-D-glucopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)]-[O-beta-D-glucopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)])-alpha-L-arabinopyranosyloleanolic acid (2).