Evaluation of anti-Mycobacterium tuberculosis activity of Campomanesia adamantium (Myrtaceae)

The anti-Mycobacterium tuberculosis activity of Campomanesia adamantium fruits extracts were evaluated. Six compounds, identified as flavanones and chalcones were quantified by HPLC-DAD-UV. Promising antitubercular activity was observed with ethyl acetate extract (MIC 62.5 µg/mL) and their fractions (MIC values ranging from 39 to above 250 µg/mL). The better MIC result of 39 µg/mL was associated with two fractions that contain bigger amounts of 5,7-dihydroxy-6, 8-di-C-methylflavanone and 2',4'-dihydroxy-3',5'-dimethyl-6'-methoxychalcone. These compounds exhibited MICs >250 and 62.5 µg/mL, respectively, while their mixtures showed values ranging from 62.5 to 7.8 µg/mL, demonstrating a synergism between them.

Constituintes químicos e atividade antioxidante de extratos das folhas de Terminalia fagifolia Mart. et Zucc

Phytochemical investigation of ethanolic leaves extracts of T. fagifolia led to the isolation of (+)-catechin, sitosterol-3-O-β-D-glucopyranoside, α- and β-tocopherol, a mixture of lupeol, α- and β-amyrin, sitosterol and a mixture of glicosid flavonoids (CP-13). The structures of these compounds were identified by ¹H and 13C NMR spectral analysis and comparison with literature data. Absolute configuration of the catechin was determinate by circular dichroism. Antioxidant activity (EC50), evaluated by 2,2-diphenyl-1-picrylhidrazyl (DPPH) assay system, decreased in the order: (+)-catechin > hydroalcoholic fraction > CP-13 > aqueous fraction > EtOH extract.

Metabólitos secundários da família bromeliaceae

This review describes aspects of the Bromeliaceae family dealing the traditional applications, biological activities and distribution of secondary metabolites in distinct subfamilies. Some species are used with medicinal purposed in the treatment of respiratory, diabetes or inflammation diseases, and gastrointestinal disorders. Special emphasis on cycloartane triterpenoids and flavonoids, typical metabolites of this family, are presented. Bromeliaceae is unique amongst the monocotyledons in the frequency and variety of flavonoids with hydroxylation or methoxylation at the 6-position. Other compound classes as steroids, hidroxycinnamic acids, phenylpropane diglycerides, lignans, are presented.

Toxicidade e atividade antioxidante de flavonoides das cascas das raízes de Lonchocarpus filipes

The phytochemical investigation of dichloromethane extract from root bark of Lonchocarpus filipes Benth (Leguminosae) afforded four flavonoids including three dibenzoylmethane derivatives rarely found in nature. The structures were established based on their spectral data (¹H and 13C NMR, 2D-NMR) as being: lanceolatin B (1), pongamol (2), (E)-7-O-methylpongamol (3) and (E)-9-O-methylpongamol (4). Compound (4) is described herein for the first time as a natural product. The extracts and the isolated compounds (1), (2) and (3) displayed high toxicity in the brine shrimp lethality assay. Only compound (2) showed antioxidant activity using a DPPH radical scavenging assay. This is the first report on the phytochemical study of Lonchocarpus filipes.

Enriquecimento de compostos fenólicos de folhas de Inga edulis por extração em fase sólida: quantificação de seus compostos majoritários e avaliação da capacidade antioxidante

A phenolic fraction was obtained from of the acetone-water-acetic acid extract of Inga edulis leaves, by liquid-liquid partition and SPE-C18 cartridges. This method provided an increase of 108, 66, 51, 50 and 36% of flavonols, proanthocyanidins, total polyphenols, gallotannins and flavanols, respectively. The major phenolics in purified fraction were procyanidin B2, catechin and myricetin-3-O-α-L-rhamnopyranoside, which achieved increases of 111, 47 and 45%, respectively, after SPE. Acid hydrolysis confirmed the presence of procyanidins, prodelphinidins and glycosylated flavonoids.

Otimização de metodologia analítica para o doseamento de flavonoides de Bauhinia cheilantha (Bongard) Steudel

The present study examined the optimization of stabilization and extraction processes of the flavonoids of Bauhinia cheilantha (Bongard) Steudel. Four drying temperatures (room temperature, 40, 60 and 80 ºC) and seven extraction systems (distilled water, 100% methanol, 80% methanol, 100% ethanol, 80% ethanol, 80% acetone and 60% acetone) were examined. The results demonstrated a reduction in flavonoid levels with increasing drying temperatures; and 80% acetone, 80% ethanol, and methanol p.a extraction systems were found to be most efficient and its weren't differents statisticaly (p<0.05).

Aromatic compounds from three Brazilian Lauraceae species

Phytochemical investigations on three Brazilian Lauraceae species from the Cerrado region of São Paulo State, Ocotea corymbosa (Meins) Mez., O. elegans Mez. and Persea pyrifolia Nees & Mart. ex Nees resulted in the isolation of flavonoids, an ester of the 4-O-E-caffeoylquinic acid, an aromatic sesquiterpene besides furofuran lignans. This is the first chemical study on the leaves of Ocotea elegans and O. corymbosa as well as the first report of non-volatile compounds from Persea pyrifolia.

Feoforbídeo (etoxi-purpurina-18) isolado de Gossypium mustelinum (Malvaceae)

The phaeophorbide ethyl ester named Purpurin-18 and the flavonoids quercetin and kaempferol were obtained by chromatographic procedures from the chloroform fraction of aerial parts of Gossypium mustelinum. The structure of these compound was determined by NMR, IR and mass spectra data analysis. This is the first occurrence of this compound in Angiosperm.

In vitro study of antioxidant and scavenger properties of phenolic compounds from Lychnophora species

This paper describes the antioxidant effects of thirteen phenolic compounds isolated from plants of the genus Lychnophora. Two assays were performed to evaluate these effects: a cellular test that measured the luminol-enhanced chemiluminescence produced by neutrophils stimulated with opsonized zymosan and a cell-free test involving horseradish peroxidase-H2O2-luminol. In both assays, the antioxidant activity of the phenolic compounds was dependent on their concentration and chemical structure. Our results suggest that the ability of phenolic compounds from Lychnophora species to scavenge and inhibit the generation of ROS may be a mechanism underlying the anti-inflammatory activity of extracts from Lychnophora spp.

Blainvillea rhomboidea: constituintes químicos e atividade citotóxica

The phytochemical investigation of the ethanol extract from the aerial parts of Blainvillea rhomboidea (Asteraceae) resulted in the isolation and characterization of 8β-tigloyloxy-grazielia acid, together with the flavonoids derrone, acacetin, luteolin and luteolin 7-methyl ether, and p-(1-methyl-ethan-1-ol)-phenol. The structures of all compounds were determined by spectroscopic methods (¹H and 13C NMR and HREIMS) and comparison with published spectral data. The flavonoids luteolin and 7-O-metyl-luteolin, isolated from the active dichloromethane fraction, showed moderate cytotoxic activity.

Determination of rutin and narcissin in marigold extract and topical formulations by liquid chromatography: applicability in skin penetration studies

A chromatographic technique for determination of rutin and narcissin in marigold extract and topical formulations was developed and validated. The method shows linearity over the concentration range of 0.2 - 6.0 μg/mL of rutin (r = 0.9986) and 0.8 - 12.0 μg/mL of narcissin (r = 0.9951). The values obtained for precision and accuracy are in agreement with ICH guidelines. Both the formulation excipients and the porcine ear skin samples did not interfere with the flavonoids determination. The recovery of rutin and narcissin in skin samples added with marigold extract was 81.41% and 83.35%, respectively, which demonstrate the applicability of this method to perform skin penetration studies.

Flavonoides e outras substâncias de Lippia sidoides e suas atividades antioxidantes

The chemical investigation of the ethanol extracts of stems, roots and leaves of Lippia sidoides led to the isolation of: steroid β-sitosterol, naphthoquinone tecomaquinone, monoterpene carvacrol, flavonoid 4',5,7-trihydroxyflavanone (naringenin), 3',4',5,7-tetrahydroxyflavanone and 4',5,7-trihydroxy-6-methoxyflavone flavonoids mixture, and 3,4,4',6'-tetrahydroxydihydrochalcone-2'-O-β-D-glucopyranoside and 4,4',6'-trihydroxydihydrochalcone-2'-O- β-D-glucopyranoside dihydrochalcones mixture. Their structures were characterized on the basis of spectral data, mainly ¹H and 13C NMR (1D and 2D) and mass spectra. The ethanol extract and isolated compounds were evaluated for their antioxidative properties using the method of inhibition of free radical DPPH (2,2-diphenyl-1-picrylhydrazyl).

Lychnophorinae (asteraceae): a survey of its chemical constituents and biological activities

This work reviews the current literature about the chemical constituents and the biological activities of the subtribe Lychnophorinae (Vernonieae, Asteraceae). The notable secondary metabolites are sesquiterpene lactones of furanoheliangolide (goyazensolide and eremantholide types) and flavonoids. Some of its most investigated activities include its anti-inflammatory, analgesic, antimicrobial and cytotoxic activities, specially for the Lychnophora and Eremanthus species. The data presented on this paper not only displayed the role played by the Lychnophorinae species as a source of bioactive compounds, but also reinforced the need of further studies involving the species of such subtribe.

Flavonoides de Lonchocarpus campestris (Leguminosae)

A new flavone named 3,4',5,6-tetramethoxy-[2'',3'':7,8]furanoflavone besides the known flavonoids (2S,3R,4S)-3,4,5,8-tetramethoxy-[2'',3'':6,7]-furanoflavan, 3,6-dimethoxy-2'',2''-dimethylcromene-[2'',3'':7,8] -flavone, 3,5,6-trimethoxy-[2'',3'':7,8]-furanoflavone, 2,4',4,5-tetramethoxy-[2'',3'':6,7]-furanodihydroaurone, (2R,3S,4S)-3,4,5,6-tetramethoxy-[2'',3'':7,8]-furanoflavan and 3',4'-methylenodioxy-5,6-dimethoxy-[2'',3'':7,8]-furanoflavone were isolated from the root barks of Lonchocarpus campestris. The complete ¹H and 13C NMR assignments of the new furan flavonoid was performed using 1D and 2D pulse sequences, including COSY, HMQC and HMBC experiments.

Glicoalcaloides antifúngicos, flavonoides e outros constituintes químicos de Solanum asperum

Two glycoalkaloids: solamargine and solasonine; three flavonoids: tiliroside, 7-O-α-L-ramnopyranosyl-kaempferol and 3-O-[ß-D-glucopyranosyl-(1→6)-α-L-ramnopyranosyl]-7- O-α-L-ramnopyranosyl-kaempferol, in addition to the tripeptide Leu-Ile-Val, the aminoacid proline and the eicosanoic acid were isolated from Solanum asperum (Solanaceae). The structures of all compounds were determined by interpretation of their spectra (IR, MS, ¹H and 13C NMR) and comparison with the literature data. All compounds, except the glycoalkaloids, are being reported for the first time for S. asperum. Solasonine showed strong activity (MIC < 0.24 μg/mL) against four filamentous fungi species of the genera Microsporum and Trichophyton.