ABSTRACT
A protocol was developed for the micropropagation of Plumbago scandens L. from the shoot tip and node explants.The best response of shoot elongation (10.18±2.01 mm) was observed on MS basal medium supplemented with 0.02 mg/L IAA – 0.02 mg/L GA3. The maximum number of root induction (10.0±2.21) and shoot elongation (8.24±3.24 mm) was observed on medium containing 0.01 mg/L IBA and 0.01 mg/L GA3. The in vitro propagated plants were transferred to soil with 80% survival rate. Profuse compact callus was induced and proliferated from several explants (cotyledons, internodes, hypocotyls and roots) cultured on MS medium supplemented with all the combinations of 2,4-D – GA3 or 2,4-D alone and combinations of IAA – BAP or IAA alone, and the highest percentage of friable callus (90%) were induced in the sections of compact callus using 2.0 mg/L IAA – 0.02 mg/L BAP – 0.5 mg/L GA3.The qualitative determination of chemical constituents in the extracts was evaluated by a gas chromatography coupled to a mass spectrometry, and it was verified the presence of plumbagin only in root extracts but not in in vitro plantlets.The antibacterial activity of root extracts against various pathogenic bacteria, and the minimum inhibitory concentrations (MICs) was determined. Chloroform extracts showed good antibacterial activity against Neisseria gonorrhoeae between 0.4 to 1.0 mg/L with 20.4 to 30.0 mm (diameter zone of inhibition); inhibition against Staphylococcus aureus was moderate, and lower against Escherichia coli. Chloroform extracts had the lowest MICs for N. gonorrhoeae (<0.1 mg/mL per disc), and the activities against S. aureus (MIC 0.2 mg/mL) and E. coli (MIC 0.4 mg/mL) were less pronounced.
ABSTRACT
The aim of this work was to study the phytochemical and antifungal activity of anthraquinones and root and leaf extracts of Coccoloba mollis on phytopathogens. The chemical analysis of ethanolic extracts showed a mixture of long-chain hydrocarbons, carboxyl esters and 3-taraxerone in the leaf extract. Two anthraquinones (emodin and physcion) were isolated and identified from the root extract. Phytochemical screening using the pharmacognostic methods revealed the presence of flavonoids and tannins in the leaves and roots. Anthraquinones were only found in the root extract, no alkaloids, coumarins, saponins and simple phenolics were present. The antifungal activity of C. mollis extracts and anthraquinones isolated from the root of this plant against Botryospheria ribis, B. rhodina, Lasiodiplodia theobromae and Fusarium sp showed promising results for their use as fungicides, where emodin was the most active compound, which inhibited the microorganisms tested up to 44 percent.
ABSTRACT
The present study describes the chemical composition and antimicrobial activity of essential oils obtained by hydrodistillation from the leaves of Pimenta pseudocaryophyllus (1.0 percent w/w) and Tynanthus micranthus (1.1 percent w/w). GC and GC/MS analysis demonstrated that eugenol was the only component in the T. micranthus essential oil (99.9 percent) and the major component in the P. pseudocaryophyllus essential oil (92.59 percent), which also presented methyleugenol, terpinen-4-ol, o-cymene and (E)-caryophyllene, among others. Both the oils presented antimicrobial activity against bacteria, yeast and filamentous fungi tested.The Bioautography test revealed that eugenol was the bioactive component in both the oils against Cladosporium herbarum. This is the first report about the T. micranthus essential oil, and the antifungal activity of P. pseudocaryophyllus. The results confirmed the potential of eugenol-rich essential oils not only as a source of flavor compounds, but also of use as antimicrobial agent in agriculture and in pharmaceutical and food products.
O presente trabalho descreve a análise da composição química e a avaliação da atividade antimicrobiana dos óleos essenciais obtidos por hidrodestilação das folhas de Pimenta pseudocaryophyllus (1.0 por cento m/m) e de Tynanthus micranthus (1.1 por cento m/m). As análises por CG e CG-EM demonstraram que o óleo essencial de P. pseudocaryophyllus apresenta o eugenol como componente principal (92.6 por cento ), além de outros constituintes como methyleugenol, tepinen-4-ol, O-cimeno e (E)-cariofileno. O óleo de T. micranthus contém o eugenol como único constituinte (99.9 por cento). Ambos os óleos apresentaram atividade contra bactérias, leveduras e fungos filamentosos. O teste de bioautografia revelou o eugenol como a substância responsável pela atividade contra o Cladosporium herbarum dos óleos das duas espécies. Este é o primeiro estudo sobre o óleo essencial de T. micranthus e o primeiro relato sobre a atividade antifúngica do óleo essencial de P. pseudocaryophyllus. Os resultados obtidos confirmaram o potencial de óleos essenciais ricos em eugenol para uso como agentes antimicrobianos na agricultura e na preparação de produtos alimentícios e farmacêuticos.
ABSTRACT
The chemical study of Spathodea campanulata (Bignoniaceae) roots peels afforded an iridoid glucoside(ajugol) and two phenolic derivatives (p-hydroxy-benzoic acid and methyl p-hydroxy-benzoate). Thecompounds were characterized upon spectral data interpretation. Bioactivities of the constituents wereevaluated against fungus Cladosporium herbarum.
O estudo químico das cascas das raízes de Spathodea campanulata (Bignoniaceae) conduziu ao isolamentode um irióide glicosilado (ajugol) e dois derivados fenólicos (ácido p-hidroxi-benzóico e p-hidroxi-benzoato demetila). Os compostos foram identificados com base na interpretação dos seus dados espectrais. A atividadebiológica destes constituintes foi avaliada contra o fungo Cladosporium herbarum