Phytochemical study of Gypsophila trichotoma wend. (Caryophyllaceae)

Phytochemical studies of ethyl acetate extracts from the roots and aerial parts of Gypsophila trichotoma revealed the presence of stigmast-7-en-3-ol, stigmasta-7,22-dien-3-ol (spinasterol), ergost-7-en-3-ol, stigmasta-3,5dien7-one, β-sitosterol, 22,23-dihydrospinasterone, vitexin, orientin, homoorientin and hyperoside. The structures of the compounds were determined by GC/MS and HPLC analyses.

Constituintes químicos de Vernonia chalybaea mart.

The chemical investigation of the hexane and ethanol extracts from aerial parts of Vernonia chalybaea conducted to the isolation and characterization of a new aliphatic tetrahydroxyl ether, along with a series of known compounds such as 4 α,10 α-epoxyaromadendrane, friedelin, taraxasteryl acetate, pseudotaraxasteryl acetate, lupeyl acetate, lupeol, α-amiryn, β-amiryn, β-sitosterol, stigmasterol, 2,3-dimethyl-1,2,3-tri-hydroxybuthanol, angophorol, angophorol-7-O-glucoside, angophorol-7-O-rutinoside, 3,7-dimethoxy-5,3',4'-trihydroxyflavone and acacetin. The structures of all compounds were determined by spectroscopic analysis and comparison with published spectral data.

Constituintes químicos de Sebastiania macrocarpa Muell. Arg. (Euphorbiaceae)

The chemical investigation of the methanolic extract of the aerial part of Sebastiania macrocarpa allowed the isolation of the mixture of steroids β-sitosterol and stigmasterol, gallic acid, and scopoletin. The hexane extract of the roots allowed the isolation of the triterpene lupeol and of the macrociclic diterpene (+)-tonantzitlolone. The structures of all compounds isolated were identified on the basis of their spectral data and by comparison of their spectral data with values described in the literature. This is the first report involving the chemical investigation of this species.

Estudos químicos e biológicos de Microgramma vacciniifolia (Langsd. & Fisch.) Copel (Polypodiaceae)

Chemical studies with aerial parts of Microgramma vacciniifolia (Langsd. & Fisch.) Copel. afforded ²-sitosterol, hopan-22-ol, 6-metoxiapinenin-7-O-²-D-allopyranoside and a mixture containing ethyl esters of carboxilic acids. The structures of the coumpounds were elucidated by spectroscopy and GC-MS analysis. The total phenolics contents of the crude extract and fractions were determined by Folin-Ciocalteau method. The antioxidant activity was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH). The AcOEt fraction showed better activity in DPPH assay (9.9 ± 0.03 µg/mL), and presented also higher contents of the total phenolic (93.60 ± 1.11 µg/mg). Antimicrobial and allelopathic effects of the crude etanolic extract and fractions also were evaluated. In addition, the combination of biological activities was discussed.

Antifungal iridoids, triterpenes and phenol compounds from Alibertia myrciifolia Sprunge Ex. Schum

The new iridoid glucoside 10-O-vanilloyl-geniposidic acid has been isolated from the aerial parts of Alibertia myrciifolia along with hydroxyhopanone, 3α,22-dihydroxyhopane, ursolic acid, luteolin-3´,4´-dimethyl ether, caffeic acid and geniposidic acid. The structures of the isolated compounds were determined by means of mass spectrometry and nuclear magnetic resonance spectral analyses. The antifungal activities of the iridoids 10-O-vanilloyl-geniposidic acid and geniposidic acid were evaluated against the phytopathogenic fungi strains Colletotrichum gloeosporioides, Fusarium solani and Aspergillus niger.

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.

Caldensinic acid, a benzoic acid derivative and others compounds from Piper carniconnectivum

A benzoic acid derivative - caldensinic acid; E-phytyl hexadecanoate; β-sitosterol and stigmasterol mixture and phaeophytin a were isolated from the aerial parts of Piper carniconnectivum. The structures of these compounds were established unambiguously by IR, MS, 1D and 2D NMR analysis.

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.

Identificação de alguns constituintes químicos de Indigofera hirsuta Linn. (Fabaceae) por CLAE-IES-EM (TOF) e avaliação da atividade antirradicalar

A rapid analytical approach, suitable to characterize the compounds present in the aqueous and methanol extracts prepared from the aerial parts of Indigofera hirsute, was developed. The method based on high-performance liquid chromatography coupled to mass spectrometry, electrospray positive ionization and detection by time of flight (HPLC-ESI-MS-TOF) identified, tryptophan, uracil, rutin, kaempferol-3-O-β-D-glucopyranoside, gallic acid and methyl gallate. The antiradical activity of this extract was evaluated using DPPH assay, with gallic acid as antiradical pattern. The study revealed the antiradical activity of methyl galatte (EC50 = 5 ± 0.3 µg mL-1) galic acid (EC50 = 5 ± 0.2 µg mL-1) and rutin (EC50 = 21.6 ± 0.6 µg m L-1), isolated from methanol extract (EC50 = 67.7 ± 0.9 µg mL-1), which showed strong antiradical activity.

Phenolic compounds from Sidastrum micranthum (A. St.-Hil.) fryxell and evaluation of acacetin and 7,4'-Di-O-methylisoscutellarein as motulator of bacterial drug resistence

From the aerial parts of Sidastrum micranthum (A. St.-Hil.) Fryxell (Malvaceae) were isolated m-methoxy-p-hydroxy-benzaldehyde, o-hydroxy-benzoic acid, acacetin, quercetin, 7,4′-Di-O-methylisoscutellarein, genkwanin and tiliroside. These compounds were identified by data analyses of spectroscopic methods. Although acacetin and 7,4′-Di-O-methylisoscutellarein did not display relevant antibacterial activity (MIC = 256 µg/mL), they modulated the activity of antibiotics, i.e. in combination with antibiotics at 64 µg/mL (¼ MIC), a two-fold reduction in the MIC was observed for norfloxacin and ethidium bromide; regarding tetracycline and erythromycin a two-fold reduction in the MIC was observed only with 7,4′-Di-O-methylisoscutellarein.

Phaeophytins from Thyrsacanthus ramosissimus Moric. with inhibitory activity on human dna topoisomerase II-α

Our study reports the extraction and isolation of a new phaeophytin derivative 15¹-hydroxy-(15¹-S)-porphyrinolactone, designated anamariaine (1) herein, isolated from the chloroform fraction of aerial parts of Thyrsacanthus ramosissimus Moric. along with the known 15¹-ethoxy-(15¹-S)-porphyrinolactone (2). These compounds were identified by usual spectroscopic methods. Both compounds were subjected to in vitro (inhibitory activity) tests by means of supercoiled DNA relaxation techniques and were shown to display inhibitory activity against human DNA topoisomerase II-α at 50 µM. Interconversion of these two pigments under the mild conditions of the isolation techniques should be highly unlikely but cannot be entirely ruled out.

Constituintes químicos de Vernonia scorpioides (Lam) Pers. (Asteraceae)

The chemical investigation of hexane and ethanol extracts from the aerial parts of Vernonia scorpioides resulted in the isolation and characterization of a new polyacetylene lactone, rel-4-dihydro-4β-hydroxy-5a-octa-2,4,6-triynyl-furan-2-(5H)-one, along with the new ethyl 3,4-dihydroxy-6,8,10-triynyl-dodecanoate, and seven known compounds: taraxasteryl acetate, lupeyl acetate, lupeol, lupenone, β-sitosterol, stigmasterol and luteolin. The structure of all compounds was determined by spectrometric techniques (HR-ESI-MS, ¹H and 13C NMR and IV) and comparison with published spectral data.

Isolamento do verbacosídeo e validação de método analítico para padronização do extrato bruto das partes aéreas de Buddleja stachyoides Cham. & Schltdl. (Scrophulariaceae)

Phenylpropanoid glycoside verbascoside was isolated and identified from the ethyl acetate fraction of the aerial parts of Buddleja stachyoides Cham. & Schltdl. by 1H-NMR. A method using high-performance liquid chromatography has been developed and validated for determination of verbascoside in alcoholic crude extract of the aerial parts of B. stachyoides. Analysis was performed on a Phenomenex® Gemini-NX C18 analytical column (250 mm × 4.6 mm; 5 µm) using a mobile phase (pump A - aqueous solution containing H2SO4 (0.01 M), H3PO4 (0.4%), and (C2H5)2NH (0.4%); pump B - methanol:aqueous (95:5) solution containing H2SO4 (0.05 M), H3PO4 (2%), and (C2H5)2NH (0.2%); pump C - acetonitrile:aqueous (90:10) solution containing H2SO4 (0.05 M) and H3PO4 (2%)) and a diode array detector at 325 nm. The method was validated in accordance with ANVISA guidelines and may be applied to quality control of herbal medicine with aerial parts of B. stachyoides.

Actividad insecticida sobre Spodoptera frugiperda (Lepidóptera: Noctuidae) de los compuestos aislados de la parte aérea de Piper septuplinervium (Miq.) c. dc. y las inflorescencias de Piper subtomentosum Trel. & Yunck. (Piperaceae)

The bioassay-guided purification of ethanolic extracts from inflorescences of Piper subtomentosum Trel. & Yunck and aerial part of Piper septuplinervium (Miq. ) C. DC. led to isolation of five flavonoids, uvangoletin (1), galangin (2), chrysin (5), 5-hydroxy-4',7-dimethoxy-flavone (6), pinostrobin (7); one amide, N-p-coumaroil-tyramine (4); one acylglycerol, monopalmitin (3); one derivative of acid, protocatechuic acid (8); and glycosydated sterol, daucosterol (9). Their structures were elucidated on the basis of spectroscopy and spectrometry data and by comparison with data reported in the literature. The isolated compounds were tested against Spodoptera frugiperda. The results showed galangin and protocatechuic acid to be the most active (LC 50 13.63 and 17.16 ppm, respectively).

HPLC-DAD based method for the quantification of flavonoids in the hydroethanolic extract of Tonina fluviatilis Aubl. (Eriocaulaceae) and their radical scavenging activity

This article describes the isolation and identification of flavonoids in the hydroethanolic extract of the aerial parts from Tonina fluviatilis and evaluation of their antiradical activity. A method based on HPLC-DAD was developed and validated for detecting and quantifying flavonoids in hydroethanolic extracts. The flavonoids identified and quantified in the extract were 6,7-dimethoxyquercetin-3-O-β-D-glucopyranoside (1), 6-hydroxy-7-methoxyquercetin-3-O-β-D-glucopyranoside (2), and 6-methoxyquercetin-3-O-β-D-glucopyranoside (3). The developed method presented good validation parameters, showing that the results obtained are consistent and can be used in ensuring the quantification of these constituents in the extracts. Compounds 2 and 3 showed strong antiradical activity when compared with the positive controls (quercetin and gallic acid).