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1.
Fitoterapia ; 173: 105820, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38211642

RESUMO

In this study, we specifically focused on the crude methanolic leaf extract of Byrsonima coccolobifolia, investigating its antifungal potential against human pathogenic fungi and its antiviral activity against COVID-19. Through the use of high-performance liquid chromatography coupled with electrospray ionization ion trap tandem mass spectrometry, direct infusion electrospray ionization ion trap tandem mass spectrometry, and chromatographic dereplication procedures, we identified galloyl quinic acid derivatives, catechin derivatives, proanthocyanidins, and flavonoid glycosides. The broth dilution assay revealed that the methanolic leaf extract of B. coccolobifolia exhibits antifungal activity against Cryptococcus neoformans (IC50 = 4 µg/mL). Additionally, docking studies were conducted to elucidate the interactions between the identified compounds and the central residues at the binding site of biological targets associated with COVID-19. Furthermore, the extract demonstrated an in vitro half-maximum effective concentration (EC50 = 7 µg/mL) and exhibited significant selectivity (>90%) toward SARS-CoV-2.


Assuntos
COVID-19 , Extratos Vegetais , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antifúngicos , Estrutura Molecular , SARS-CoV-2 , Espectrometria de Massas por Ionização por Electrospray/métodos , Metanol , Antivirais/farmacologia , Cromatografia Líquida de Alta Pressão/métodos
2.
Appl Microbiol Biotechnol ; 107(19): 6103-6120, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37561179

RESUMO

Bacillus subtilis species complex is known as lipopeptide-producer with biotechnological potential for pharmaceutical developments. This study aimed to identify lipopeptides from a bacterial isolate and evaluate their antifungal effects. Here, we isolated and identified a lipopeptide-producing bacterium as a species of Bacillus subtilis complex (strain UL-1). Twenty lipopeptides (six iturins, six fengycins, and eight surfactins) were identified in the crude extract (CE) and fractions (F1, F2, F3, and F4), and the highest content of total lipopeptides was observed in CE and F2. The chemical quantification data corroborate with the hemolytic and antifungal activities that CE and F2 were the most hemolytic and inhibited the fungal growth at lower concentrations against Fusarium spp. In addition, they caused morphological changes such as shortening and/or atypical branching of hyphae and induction of chlamydospore-like structure formation, especially in Fusarium solani. CE was the most effective in inhibiting the biofilm formation and in disrupting the mature biofilm of F. solani reducing the total biomass and the metabolic activity at concentrations ≥ 2 µg/mL. Moreover, CE significantly inhibited the adherence of F. solani conidia on contact lenses and nails as well as disrupted the pre-formed biofilms on nails. CE at 100 mg/kg was nontoxic on Galleria mellonella larvae, and it reduced the fungal burden in larvae previously infected by F. solani. Taken together, the lipopeptides obtained from strain UL-1 demonstrated a potent anti-Fusarium effect inducing morphological alterations and antibiofilm activities. Our data open further studies for the biotechnological application of these lipopeptides as potential antifungal agents. KEY POINTS: • Lipopeptides inhibit Fusarium growth and induce chlamydospore-like structures. • Lipopeptides hamper the adherence of conidia and biofilms of Fusarium solani. • Iturins, fengycins, and surfactins were associated with antifungal effects.


Assuntos
Antifúngicos , Bacillus subtilis , Bacillus subtilis/metabolismo , Antifúngicos/química , Esporos Fúngicos/metabolismo , Biofilmes , Lipopeptídeos/metabolismo , Peptídeos Cíclicos/metabolismo , Doenças das Plantas/microbiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-37003647

RESUMO

The identification of new drugs with few or no adverse effects is of great interest worldwide. In cancer therapy, natural products have been used as chemopreventive and chemotherapeutic agents. Plants from the Brazilian savannah belonging to the Byrsonima genus are popularly known as muricis and have attracted much attention due to their various pharmacological activities. However, there are currently no data on these plants concerning their use as chemopreventive or chemotherapeutic agents in human cell lines. The present study assessed the potential of B. correifolia, B. verbascifolia, B. crassifolia, and B. intermedia extracts as natural alternatives in the prevention and/or treatment of cancer. The chemical constituents present in each extract were analyzed by electrospray ionization-mass spectrometry (ESI-MSN). The mutagenic/antimutagenic (micronucleus assay), genotoxic/antigenotoxic (comet assay), apoptotic/necrotic (acridine orange/ethidium bromide uptake), and oxidative/antioxidative (CM-H2DCFDA) effects of the extracts and their influence on gene expression (RTqPCR) were investigated in nonmetabolizing gastric (MNP01) and metabolizing hepatocarcinoma (HepG2) epithelial cells to evaluate the effects of metabolism on the biological activities of the extracts. The genotoxicity, mutagenicity, and apoptotic effects observed in HepG2 cells with B. correifolia and B. verbascifolia extracts are probably associated with the presence of proanthocyanidins and amentoflavone. In MNP01 cells, none of the four extracts showed mutagenic effects. B. crassifolia and B. intermedia extracts exhibited strong antimutagenicity and enhanced detoxification in HepG2 cells and antioxidant capacities in both types of cells, possibly due to the presence of gallic and quinic acids, which possess chemopreventive properties. This study identifies for the first time B. correifolia and B. verbascifolia extracts as potential agents against hepatocarcinoma and B. crassifolia and B. intermedia extracts as putative chemopreventive agents.


Assuntos
Anticarcinógenos , Antimutagênicos , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Brasil , Plantas , Antioxidantes/farmacologia , Mutagênicos/toxicidade , Instabilidade Genômica , Antimutagênicos/farmacologia
4.
Biomolecules ; 10(4)2020 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-32290371

RESUMO

:Machaerium hirtum (Vell.) Stellfeld (Fabaceae) known in Brazil as "jacaranda de espinho" or "espinheira santa nativa" is a medicinal plant commonly used in folk medicine to treat ulcers, cough and diarrhea. This study aimed to investigate the anti-inflammatory and antinociceptive effects of hydroalcoholic extracts from M. hirtum twig (HEMh) using in vivo experimental models of nociception through the involvement of transient receptor potential channels, acid-sensing ion channel (ASIC), nitrergic, opioidergic, glutamatergic, and supraspinal pathways. Our results revealed an antinociceptive effect of HEMh mediated by the opioidergic, L-arginine-nitric oxide and glutamate systems, as well as by interactions with TRPA1/ASIC channels. The anti-inflammatory effect of HEMh evaluated with a xylene-induced ear edema and by the involvement of arachidonic acid and prostaglandin E2 (PGE2) showed involvement of the COX pathway, based on observed decreases in PGE2 levels. A phytochemical investigation of the HEMh led to the isolation of α-amyrin, ß-amyrin, allantoin, apigenin-7-methoxy-6-C-ß-D-glucopyranoside, and apigenin-6-C-ß-D-glucopyranosyl-8-C-ß-D-xylopyranoside. In conclusion, the acute oral administration of HEMh inhibits the nociceptive behavioral response in animals through the nitrergic, opioid, glutamatergic pathways, and by inhibition of the TRPA1 and ASIC channels, without causing locomotor dysfunction. In addition, its anti-inflammatory effect is associated with the COX pathway and decreased PGE2 levels.


Assuntos
Dor Aguda/tratamento farmacológico , Fabaceae/química , Inflamação/tratamento farmacológico , Dor Aguda/complicações , Analgésicos Opioides/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Ácido Araquidônico , Arginina/metabolismo , Peso Corporal/efeitos dos fármacos , Dinoprostona/metabolismo , Edema/tratamento farmacológico , Etanol , Feminino , Formaldeído , Glutamatos/metabolismo , Indometacina/efeitos adversos , Inflamação/complicações , Canais Iônicos/metabolismo , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Óxido Nítrico/metabolismo , Nociceptividade/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/toxicidade , Testes de Toxicidade Aguda , Úlcera/induzido quimicamente , Úlcera/complicações , Úlcera/tratamento farmacológico , Xilenos
5.
Nat Prod Res ; 34(6): 884-888, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30453777

RESUMO

The analysis by HPLC-PDA of the hydroalcoholic extract of the leaves of M. eriocarpum together with the injection of the fractions containing the already identified metabolites allowed the detection of at least 5 flavonoids, of which two are derived from apigenin and three from luteolin. After isolating larger amounts of isovitexin (I), assays were performed to evaluate the allelopathic activity together with the crude extract. The results show that the initial inhibition indexes were very similar to those observed in the treatments with F17 (Fraction enriched in isovitexin) and F18 (isovitexin), mainly in the concentrations of 500 and 1000 mg L-1. The index of the number of lateral roots, an increase of the inhibitory effect is observed with the increase of the concentration of M. eriocarpum extract.


Assuntos
Alelopatia , Fabaceae/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Apigenina/isolamento & purificação , Apigenina/farmacologia , Cromatografia Líquida de Alta Pressão , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Luteolina/química , Extratos Vegetais/química , Raízes de Plantas
6.
Biomed Pharmacother ; 111: 1112-1123, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30841424

RESUMO

Byrsonima intermedia is a species of bush popularly used to treat gastrointestinal disorders, such as gastric ulcers, gastritis, and diarrhea. Previous studies have revealed that the methanolic crude extract of B. intermedia leaves has gastroprotective and healing properties. In this new study, we specifically investigated two purified partitions, ethyl acetate (EtOAc) and water (AcoAq), obtained from the crude extract to characterize the antiulcer effects of these two partitions and the mechanisms of action of this medicinal plant. The healing effects of these partitions on the gastric and duodenal mucosa were assessed after ischemia-reperfusion (I/R) or acetic acid-induced injury. The involvement of tumor necrosis factor-alpha (TNF-alpha), interleukin 1ß (IL-1ß), interleukin 10 (IL-10), and myeloperoxidase (MPO) activity and glutathione (GSH) levels were determined. The antibacterial activity against Helicobacter pylori was evaluated using microdilution methods. The phytochemical analysis of AcoAq revealed a predominance of oligomeric proanthocyanidins and galloyl quinic esters, whereas EtOAc was found to contain concentrated flavonoids. Both partitions led to a significant reduction in gastric lesions, but AcoAq was more effective than EtOAc with regard to anti-Helicobacter pylori activity in addition to protecting the gastric mucosa against ethanol, non-steroidal anti-inflammatory drugs (NSAIDs) and duodenal mucosal damage induced by cysteamine. Additionally, both partitions were associated with a significant increase in gastric and duodenal healing and increased gastric mucosal GSH content after damage induced by acetic acid. On the other hand, after 6 days of treatment, EtOAc was more effective than AcoAq in ameliorating gastric damage upon initiation of the gastric I/R, which was accompanied by a significant reduction in the activity of gastric mucosal MPO, IL 1-ß and TNF-alpha, as well as an elevation in IL-10 and GSH content. These results demonstrate that the oligomeric proanthocyanidins and galloyl quinic esters present in AcoAq were more effective in the prevention of gastric and duodenal ulcers due to the antioxidant effects of these compounds, whereas the flavonoids present in EtOAc were more effective due to their anti-inflammatory activity on the gastric and duodenal tissue. All these results confirm that the rich phytochemical diversity of B. intermedia contributes to the pharmacological actions of this medicinal plant on the gastrointestinal tract in addition to its activity against H. pylori.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Malpighiaceae/química , Úlcera Péptica/tratamento farmacológico , Animais , Antiulcerosos/farmacologia , Flavonoides/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Gastrite/tratamento farmacológico , Gastrite/metabolismo , Glutationa/metabolismo , Masculino , Medicina Tradicional/métodos , Úlcera Péptica/metabolismo , Compostos Fitoquímicos/farmacologia , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Plantas Medicinais/química , Ratos , Ratos Wistar , Estômago/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
7.
Rev. bras. farmacogn ; 26(4): 427-432, July-Aug. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-792697

RESUMO

ABSTRACT Operculina macrocarpa (L.) Urb., Convolvulaceae, is used by the population as a laxative. In this work we described the isolation of the three phenolic acids present in the hydroethanolic extract of the O. macrocarpa roots. The quantification of the caffeic, chlorogenic acids and of the new caffeic dimer in the hydroethanolic and infusion extracts was performed by high-performance liquid chromatography coupled photodiode array detector. These analyses showed the higher content of the chlorogenic, caffeic and the new 3,4'-dehydrodicaffeic acid in hydroethanolic and hydroethanolic extracts without resin in which infusion. The acid found in greater quantity is caffeic acid followed by the 3,4'-dehydrodicaffeic acid. The laxative activity was evaluated by different experimental models of intestinal transit with the hydroethanolic and infusion extracts, and the resin fraction, caffeic, chlorogenic and ferulic acids. The results showed all extracts and compounds tested had significant activity in the experimental model tested. These results obtained are essential for the future development of a pharmaceutical product with safety and efficacy.

8.
Cytotechnology ; 68(6): 2729-2744, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27344148

RESUMO

Brazilian flora biodiversity has been widely investigated to identify effective and safe phytotherapeutic compounds. Among the investigated plant species, the Byrsonima genus exhibits promising biological activities. This study aimed at evaluating the cytotoxicity of B. correifolia, B. verbascifolia, B. fagifolia and B. intermedia extracts using different assays in two cell lines (primary gastric and HepG2 cells). The different extract concentrations effects on cell viability were assayed using the MTT, aquabluer, neutral red and LDH assays. Non-cytotoxic concentrations were selected to generate cell proliferation curves and to assess cell cycle kinetics by flow cytometry. Byrsonima extracts differentially affected cell viability depending on the metabolic cellular state and the biological parameter evaluated. B. fagifolia and B. intermedia extracts exhibited lower cytotoxic effects than B. correifolia and B. verbascifolia in all assays. The results obtained with LDH and flow cytometry assays were more reliable, suggesting that they can be useful in the screening for herbal medicine and to further characterize these extracts as phytotherapeutic compounds.

9.
Mutagenesis ; 31(2): 147-60, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26314304

RESUMO

Machaerium hirtum (Vell.) Stellfeld (M.hirtum) is a plant known as 'jacarandá-bico-de-pato' whose bark is commonly used against diarrhea, cough and cancer. The aim of this study was to phytochemically characterise the hydroethanolic extract of this plant, investigate its antimutagenic activities using the Ames test and evaluate its effects on cell viability, genomic instability, gene expression and cell protection in human hepatocellular carcinoma cells (HepG2). Antimutagenic activity was assessed by simultaneous pre- and post-treatment with direct and indirect mutagens, such as 4-nitro-o-phenylenediamine (NPD), mitomycin C (MMC), benzo[a]pyrene (B[a]P) and aflatoxin B1 (AFB1), using the Ames test, cytokinesis blocking micronucleus and apoptosis assays. Only 3 of the 10 concentrations evaluated in the MTT assay were cytotoxic in HepG2 cells. Micronucleated or apoptotic cells were not observed with any of the tested concentrations, and there were no mutagenic effects in the bacterial system. However, the Nuclear Division Index and flow cytometry data showed a decrease in cell proliferation. The extract showed an inhibitory effect against direct (NPD) and indirect mutagens (B[a]P and AFB1). Furthermore, pre- and post-treated cells showed significant reduction in the number of apoptotic and micronucleated cells. This effect is not likely to be associated with the modulation of antioxidant genes, as shown by the RT-qPCR results. Six known flavonoids were identified in the hydroethanolic extract of Machaerium hirtum leaves, and their structures were elucidated by spectroscopic and spectrophotometric methods. The presence of the antioxidants apigenin and luteolin may explain these protective effects, because these components can inhibit the formation of reactive species and prevent apoptosis and DNA damage. In conclusion, the M.hirtum extract showed chemopreventive potential and was not hazardous at the tested concentrations in the experiments presented here. Moreover, this extract should be investigated further as a chemopreventive agent.


Assuntos
Antimutagênicos/farmacologia , Fabaceae/química , Extratos Vegetais/farmacologia , Antimutagênicos/química , Antimutagênicos/toxicidade , Apoptose/efeitos dos fármacos , Apoptose/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Flavonoides/química , Flavonoides/farmacologia , Flavonoides/toxicidade , Citometria de Fluxo , Expressão Gênica , Humanos , Micronúcleos com Defeito Cromossômico , Testes para Micronúcleos , Testes de Mutagenicidade , Mutação/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética
10.
J Chem Ecol ; 41(8): 716-23, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26271673

RESUMO

Harvestmen have a pair of scent glands that open through ozopores. The literature suggests a link between the morphology of the ozopore area and the emission of a defensive secretion. A previous study on a species that aggregates in open areas, where individuals are probably more easily spotted by predators, showed that this defensive secretion causes conspecifics to flee. However, it is unknown whether this behavior occurs in species that aggregate in sheltered areas, where prey are harder to find. Herein, we describe the morphology of the ozopore area, the mode of emission of the defensive secretion, and its chemical composition in the harvestman Discocyrtus pectinifemur. We also tested if the defensive secretion is used as an alarm pheromone. We found that D. pectinifemur releases the defensive secretion in different ways, one of them being as a jet. Emission as a jet contrasts with that known for all congeners previously studied, and is in accord with the expected morphology of the ozopore. We found that the defensive secretion of D. pectinifemur does not function as an alarm pheromone. The composition of the defensive secretion, a mixture of quinones, is congruent with those already described for the clade that includes Discocyrtus. Our results support the link between the morphology of the scent glands area and the emission behavior of the defensive secretion, and they suggest that the alarm pheromone function in harvestmen may be dependent on ecological factors.


Assuntos
Aracnídeos/fisiologia , Animais , Aracnídeos/anatomia & histologia , Aracnídeos/química , Feminino , Masculino , Feromônios/análise , Glândulas Odoríferas/anatomia & histologia , Glândulas Odoríferas/química , Glândulas Odoríferas/fisiologia
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