Triagem fitoquímica, atividade antioxidante e antimicrobiana in vitro de Leonotis nepetifolia / Phytochemical Screening, in vitro Antioxidant and Antibacterial Activities of Leonotis nepetifolia

Leonotis nepetifolia é uma planta popularmente conhecida como “cordão-de-frade” e pertence à família Lamiaceae. Originário da África e naturalizado no estado do Rio Grande do Sul, é utilizado na medicina popular e ayurvédica para o tratamento de diversas doenças como infecções de pele, reumatismo, tosse, dores de estômago, sedativos e outros. Diante disso, justifica-se a escolha desta planta como alvo deste estudo. O objetivo deste trabalho foi obter extrato bruto (EBFoLn), n-hexano (FHFoLn) e frações de acetato de etila (FAFoLn) de folhas de L. nepetifolia, para realizar a análise fitoquímica e avaliação in vitro de antibacteriano e antioxidante. atividades de extrato e frações. O extrato bruto (rendimento de 15%) foi obtido por maceração em metanol por 7 dias, sendo evaporado à secura e fracionado com n-hexano e acetato de etila para obtenção de FHFoLn e FAFoLn. O extrato e as frações foram analisados por meio de testes fitoquímicos qualitativos, os quais indicaram a presença de cumarinas, taninos, alcalóides, terpenos e flavonóides. A atividade antioxidante foi realizada pelo método de eliminação de radicais livres 2,2-difenil-1-picrilidrazila (DPPH), e a atividade antimicrobiana pela técnica de microdiluição em caldo contra Proteus mirabilis, Pseudomonas aeruginosa, Shigella sonnei, Klebsiella pneumonia, Salmonella typhimurium, Bacillus cereus, Enterobacter aerogenes e Morganella morganii. O extrato bruto e a fração acetato de etila apresentaram maior atividade antirradical no ensaio DPPH, com valores de IC50 de 75,88 mg / mL e 72,46 mg / mL, respectivamente. Na avaliação da atividade antibacteriana, as frações n-hexano e acetato de etila apresentaram bons resultados contra as bactérias testadas, principalmente a fração acetato de etila, com CIMs50 de 31,25 mg / mL e 62,5 mg / mL para as bactérias Enterobacter aerogenes e Klebsiella pneumoniae, respectivamente. Esses resultados demonstram que a fração acetato de etila possui metabólitos capazes de contribuir com a atividade antioxidante e antibacteriana, o que é promissor para futuros estudos que investiguem a composição química desta fração

(R)-(-)-carvone and (1R, 4R)-trans-(+)-dihydrocarvone from poiretia latifolia vogel

The essential oils of Poiretia latifolia Vogel, native and cultivated leaves (Samples A and B, respectively) and native flowers (sample C), were obtained by hydrodistillation and analyzed by GC, GC/MS and chiral phase gas chromatography (CPGC). Twenty-four compounds were identified, representing 99.25, 99.26 and 99.23% of the oils, respectively. The major constituents of the oils were the monoterpenes (S)-(-)-limonene (16.05, 27.60, 15.60%, respectively), (1R, 4R)-trans-(+)-dihydrocarvone (18.05, 0.66 and 77.80%, respectively) and (R)-(-)-carvone (61.05, 64.20 and 4.50%, respectively). The essential oils were evaluated against some strains of Gram (+) and Gram (-) bacteria, and yeast, but displayed only modest antimicrobial activity

Absolute configuration of clemateol

The present study reports the determination of absolute stereochemistry of clemateol, an irregular monoterpene containing an epoxy group, which was isolated as the main component from the essential oil of Calea clematidea (Asteraceae). Its absolute stereochemistry was unambiguously established on the basis of detailed nuclear magnetic resonance (NMR) spectroscopic evidence (3JH-H analysis, derivatization as Mosher's esters and nuclear Overhauser effect (NOESY) spectrum) and also by resonance scattering effects in the single crystal X-ray diffraction (XRD) resolution of its (R)-mandelic acid ester derivative.Fil: Pedroso, Marcelo. Universidade Federal de Santa Maria; BrasilFil: Gehn, Adriana Z.. Universidade Federal de Santa Maria; BrasilFil: Stivanin, Mateus L.. Universidade Federal de Santa Maria; BrasilFil: Larghi, Enrique Leandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Burrow, Robert A.. Universidade Federal de Santa Maria; BrasilFil: Resende, Jackson A. L. C.. Universidade Federal Fluminense; BrasilFil: Da Silva, Ubiratan F.. Universidade Federal de Santa Maria; BrasilFil: Mostardeiro, Marco A.. Universidade Federal de Santa Maria; BrasilFil: Dalcol, Ionara I.. Universidade Federal de Santa Maria; BrasilFil: Morel, Ademir F.. Universidade Federal de Santa Maria; Brasi

Chemical composition and antimicrobial activity of the essential oil from Aeolanthus suaveolens Mart. ex Spreng

The essential oils from leaves (sample A) and flowers (sample B) of Aeolanthus suaveolens Mart. ex Spreng were obtained by hydrodistillation and analyzed by GC, GC-MS, and chiral phase gas chromatography (CPGC). Six compounds have been identified from the essential oils, representing ca 94.3 and 93% of the oils corresponding to samples A and B, respectively. The major constituents of samples A and B essential oils were respectively, linalool (34.2%/34.9%), (-)-massoialactone (25.9%/17.0%) and (E)-beta-farnesene (25.4%/29.1%). The enantiomeric distribution of the monoterpene linalool was established by analysis on heptakis- (6-O-methyl-2,3-di-O-pentyl)-beta-cyclodextrin capillary column. The antimicrobial activity of the essential oil from leaves and isolated compounds was also evaluated

Sesquiterpenoids from Nectandra megapotamica (Lauraceae)

Five sesquiterpenoid oxides, named nectandrene A, B, C, D, and E, were isolated from the essential oil of the leaves of Nectandra megapotamica. Their structures were elucidated by spectroscopic analysis, and the relative configurations were proposed by their nuclear Overhauser effect (NOESY) spectrum. Three of these isolated compounds displayed significant antimicrobial activity; the compound most active had minimal inhibitory concentration (MIC) values between 3.12 and 25.0 μg mL -1 against some tested bacteria, and antifungal activity with MIC values between 12.5 and 25.0 μg mL -1

Absolute Configuration of Franganine

The absolute configuration of franganine (<b>1</b>), a cyclopeptide alkaloid isolated from the methanol root bark extract of <i>Discaria americana</i>, was established on the basis of detailed NMR spectroscopic data and X-ray diffraction analysis of its salt (<b>2</b>)