Natural Phenolic Compounds with Antithrombotic and Antiplatelet Effects: A Drug-likeness Approach.

BACKGROUND: Thrombosis is one of the major causes of morbidity and mortality in a wide range of vessel diseases. Several studies have been conducted to identify antithrombotic agents from medicinal plants, and phenolic compounds (PCs) have been shown to effectively inhibit plasma coagulation and platelet aggregation. OBJECTIVES: This study aimed to conduct a survey of the natural PCs with proven antithrombotic and antiplatelet activities, as well as to evaluate by computational modeling the physicochemical and toxicological properties of these compounds using drug-likeness approaches. METHODS: The data were collected from the scientific database: 'Web of Science', 'Scifinder', 'Pubmed', 'ScienceDirect' and 'Google Scholar', the different classes of PCs with antithrombotic or antiplatelet effects were used as keywords. These molecules were also evaluated for their Drug-Likeness properties and toxicity to verify their profile for being candidates for new antithrombotic drugs. RESULTS: In this review, it was possible to register 85 lignans, 73 flavonoids, 28 coumarins, 21 quinones, 23 phenolic acids, 8 xanthones and 8 simple phenols. Activity records for tannins were not found in the researched databases. Of these 246 compounds, 213 did not violate any of Lipinski's rules of five, of which 125 (59%) showed non-toxicity, being promising candidates for new potential antithrombotic drugs. CONCLUSION: This review arouses interest in the isolation of phenolic compounds that may allow a new approach for the prevention of both arterial and venous thrombosis, with the potential to become alternatives in the prevention and treatment of cardiovascular diseases.

Avaliação in vitro da atividade fotoprotetora do extrato hexânicode Psidium araçá (Psidium guineense sw) / In vitro evaluation of photoprotective activity of hexanic extract of Psidium araçá (Psidium guineense sw) / Evaluación in vitro de la actividad fotoprotectiva del extracto hexanico de Psidium araçá (Psidium guineense sw)

A radiação ultravioleta (UV) é um potente carcinógeno, principalmente a UV-B, capaz de provocar danos ao DNA, relacionado a formação de radiação livres. A excessiva exposição solar e sem prevenção contra os raios UV representa um grande risco para o desenvolvimento de patologias com malignidade, dentre elas o câncer de pele. O emprego de extratos vegetais brasileiros com potencial fotoprotetor é sem dúvida um caminho inovador. O araçá ou araçá-do-campo por exemplo, da família Myrtaceae, espécie Psidium guineense Sw., possui grande potencial para exploração econômica e tem boa aceitação in natura, Dessa forma, o presente estudo tem por objetivo avaliar a atividade fotoprotetora do extrato hexânico do Psidium guineense Sw. Foram realizadas varreduras de 290 a 320nm (com intervalos de 5nm) em concentrações de 50, 100, 500 e 1000µg/mL em amostras de 2,0 mL. Os dados foram aplicados à equação de Mansur para aferir o FPS in vitro. Os resultados dessa pesquisa demonstraram que o extrato hexânico de Psidium guineense Sw. apresenta significativa atividade fotoprotetora nas concentrações de 500 e 1000 µg/mL mostrando-se superior ao FPS necessário. Assim, os resultados sugerem que possa ser utilizado como alternativa fitocosmética, tornando-se uma opção mais acessível(AU)

Ultraviolet radiation (UV) is a potent carcinogen, mainly UV-B, capable of causing damage to DNA, related to the formation of free radiation. Excessive sun exposure and without prevention against UV rays represents a great risk for the development of pathologies with malignancy, including skin cancer. The use of Brazilian plant extracts with photoprotective potential is undoubtedly an innovative path. The araçá or araçá-do-campo, for example, of the Myrtaceae family, Psidium guineense Sw., Has great potential for economic exploitation and has good acceptance in natura. Thus, the present study aims to evaluate the photoprotective activity of the hexane extract of Psidium guineense Sw. Scans of 290 to 320nm (with 5nm intervals) were performed in concentrationsof 50, 100, 500 and 1000µg / mL in samples of 2.0 mL. The data were applied to Mansur equation to measure SPF in vitro. The results of this research demonstrated that the hexanic extract of Psidium guineense Sw. Has significant photoprotective activity at concentrations of 500 and 1000 µg / mL, showing itself to be superior to the necessary SPF. Thus, the results suggest that it can be used as a phytocosmetic alternative, making it a more accessible option(AU)

La radiación ultravioleta (UV) es un potente carcinógeno, principalmente UV-B, capaz de causar daño al ADN, relacionado con la formación de radiación libre. La exposición excesiva al sol y sin prevención contra los rayos UV representa un gran riesgo para el desarrollo de patologías con malignidad, incluido el cáncer de piel. El uso de extractos de plantas brasileñas con potencial fotoprotector es, sin duda, un camino innovador. El araçá o araçá-do-campo, por ejemplo, de la familia Myrtaceae, Psidiumguineense Sw., Tiene un gran potencial para la explotación económica y tiene una buena aceptación en la naturaleza. Por lo tanto, el presente estudio tiene como objetivo evaluar la actividad fotoprotectora del hexano de Psidium guineense Sw. Se realizaron exploraciones de 290 a 320 nm (con intervalos de 5 nm) en concentraciones de 50, 100, 500 y 1000 µg / ml en muestras de 2,0 ml. Los datos se aplicaron a la ecuación de Mansurpara medir SPF in vitro. Los resultados de esta investigación demostraron que el extracto hexánico de Psidium guineense Sw. Tiene una actividad fotoprotectora significativa a concentraciones de 500 y 1000 µg / ml, demostrando ser superior al SPF necesario. Por lo tanto, los resultados sugieren que puede usarse como una alternativa fitocosmética, por lo que es una opción más accesible(AU)

Phytochemical study of Pilosocereus pachycladus and antibiotic-resistance modifying activity of syringaldehyde

ABSTRACT Pilosocereus pachycladus F. Ritter, Cactaceae, popularly known as "facheiro", is used as food and traditional medicine in Brazilian caatinga ecoregion. The plant is used to treat prostate inflammation and urinary infection. The present work reports the first secondary metabolites isolated from P. pachycladus. Therefore, the isolated compound 4-hydroxy-3,5-dimethoxy benzaldehyde (syringaldehyde) was evaluated as modulator of Staphylococcus aureus pump efflux-mediated antibiotic resistance. The isolation of compounds was performed using chromatographic techniques and the structural elucidation was carried out by spectroscopic methods. In order to evaluate syringaldehyde ability to modulate S. aureus antibiotic resistance, its minimum inhibitory concentrations (µg/ml) was first determinate, then, the tested antibiotics minimum inhibitory concentrations were determined in the presence of the syringaldehyde in a sub-inhibitory concentration. The chromatographic procedures led to isolation of twelve compounds from P. pachycladus including fatty acids, steroids, chlorophyll derivatives, phenolics and a lignan. The syringaldehyde did not show any antibacterial activity at 256 µg/ml against S. aureus. On the other hand the compound was able to reduce the antibiotic concentration (tetracycline, norfloxacin, ethidium bromide) required to inhibit the growth of drug-resistant bacteria, showing the ability of syringaldehyde of inhibiting the efflux pump on these bacteria.

Alkaloids and Phenolic Compounds from Sida rhombifolia L. (Malvaceae) and Vasorelaxant Activity of Two Indoquinoline Alkaloids.

The follow-up of phytochemical and pharmacological studies of Sida rhombifolia L. (Malvaceae) aims to strengthen the chemosystematics and pharmacology of Sida genera and support the ethnopharmacological use of this species as hypotensive herb. The present work reports phytoconstituents isolated and identified from aerial parts of S. rhombifolia by using chromatographic and spectroscopic methods. The study led to the isolation of scopoletin (1), scoporone (2), ethoxy-ferulate (3), kaempferol (4), kaempferol-3-O-ß-d-glycosyl-6''-α-d-rhamnose (5), quindolinone (6), 11-methoxy-quindoline (7), quindoline (8), and the cryptolepine salt (9). The alkaloids quindolinone (6) and cryptolepine salt (9) showed vasorelaxant activity in rodent isolated mesenteric arteries.

Phytoconstituents from Sidastrum micranthum (A. St.-Hil.) Fryxell (Malvaceae) and antimicrobial activity of pheophytin a

abstract Sidastrum micranthum (A. St.-Hil.) Fryxell, a member of the Malvaceae family, is called malva preta in Brazil. As this species is commonly used to treat bronchitis, cough, and asthma, better knowledge of its chemical compounds is important. The phytochemical study of its hexane extract, using chromatographic techniques, led to isolation of six compounds: the triterpene isoarborinol, a mixture of sitosterol and stigmasterol, sitosterol-3-O-β-D-glucopyranoside, pheophytin a, and 132-hydroxy-(132-S)-pheophytin a. Structural identification of these compounds was carried out using spectroscopic methods such as IR and 1D and 2D NMR (HOMOCOSY, HMQC, HMBC, and NOESY). Compounds isolated from S. micranthum were screened for their in vitro antifungal and antibacterial activity against twenty fungal and bacterial standard strains. Pheophytin a exhibited antimicrobial action against all microorganisms tested.

resumo Sidastrum micranthum (A. St.-Hil.) Fryxell, pertencente à família Malvaceae, é conhecida no Brasil como "malva preta". A espécie é popularmente usada contra bronquite, tosse e asma, mostrando a relevância de conhecer melhor sua composição química. O estudo fitoquímico do extrato hexânico da espécie, utilizando técnicas cromatográficas, conduziu ao isolamento de seis compostos: o triterpeno isoarborinol, mistura de sitosterol e estigmasterol, sitosterol-3-O-β-D-glicopiranosídeo, feofitina a e de 132-hidroxi-(132-S)-feofitina a. A identificação estrutural destes compostos foi realizada com base em métodos espectroscópicos, tais como IV, RMN 1D e 2D (HOMOCOSY, HMQC, HMBC e NOESY). As substâncias isoladas de Sidastrum micranthum foram avaliadas quanto às suas atividades antimicrobianas in vitro, contra vinte cepas fúngicas e bacterianas. A feofitina a mostrou ação antimicrobiana contra todos os microrganismos testados.