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1.
Nat Prod Res ; 36(11): 2907-2912, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34034579

RESUMO

Spiranthera odoratissima A. St.-Hil. (Rutaceae) has been popularly used against abdominal pain and rheumatism. This study aimed at extracting hexane from S. odoratissima (HE-SO) leaves to identify and quantify its volatile compounds by GC-MS and GC-FID and to evaluate its antifungal, antileishmanial and antibacterial activities in vitro. HE-SO exhibited antileishmanial activity against promastigote forms of Leishmania (Leishmania) amazonensis (IC50 = 38.16 µg/mL) and was moderately active against Xylella fastidiosa (MIC = 100 µg/mL). HE-SO also showed remarkable antifungal potential against six strains of Candida species, i. e., C. albicans, C. glabrata, C. parapsilosis, C. krusei, C. tropicalis and C. orthopsilosis. The lowest MIC values were between 31.25 and 250 µg/mL. Spathulenol (20.2%), τ-cadinol (11.7%), α-cadinol (9.4%), caryophyllene oxide (9.2%) and isoaromadendrene epoxide (8.2%) were the major components identified in HE-SO. Therefore, results showed that HE-SO has promising antileishmanial and antifungal actions.


Assuntos
Antiprotozoários , Leishmania mexicana , Leishmania , Óleos Voláteis , Rutaceae , Antifúngicos/química , Antiprotozoários/farmacologia , Candida , Candida glabrata , Hexanos , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Folhas de Planta/química , Xylella
2.
Int J Biol Macromol ; 185: 494-512, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34197854

RESUMO

Snakebite envenoming is the cause of an ongoing health crisis in several regions of the world, particularly in tropical and neotropical countries. This scenario creates an urgent necessity for new practical solutions to address the limitations of current therapies. The current study investigated the isolation, phytochemical characterization, and myotoxicity inhibition mechanism of gallic acid (GA), a myotoxin inhibitor obtained from Anacardium humile. The identification and isolation of GA was achieved by employing analytical chromatographic separation, which exhibited a compound with retention time and nuclear magnetic resonance spectra compatible with GA's commercial standard and data from the literature. GA alone was able to inhibit the myotoxic activity induced by the crude venom of Bothrops jararacussu and its two main myotoxins, BthTX-I and BthTX-II. Circular dichroism (CD), fluorescence spectroscopy (FS), dynamic light scattering (DLS), and interaction studies by molecular docking suggested that GA forms a complex with BthTX-I and II. Surface plasmon resonance (SPR) kinetics assays showed that GA has a high affinity for BthTX-I with a KD of 9.146 × 10-7 M. Taken together, the two-state reaction mode of GA binding to BthTX-I, and CD, FS and DLS assays, suggest that GA is able to induce oligomerization and secondary structure changes for BthTX-I and -II. GA and other tannins have been shown to be effective inhibitors of snake venoms' toxic effects, and herein we demonstrated GA's ability to bind to and inhibit a snake venom PLA2, thus proposing a new mechanism of PLA2 inhibition, and presenting more evidence of GA's potential as an antivenom compound.


Assuntos
Anacardium/química , Ácido Gálico/farmacologia , Miotoxicidade/tratamento farmacológico , Inibidores de Fosfolipase A2/farmacologia , Fosfolipases A2/metabolismo , Venenos de Serpentes/enzimologia , Animais , Modelos Animais de Doenças , Ácido Gálico/química , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Miotoxicidade/enzimologia , Miotoxicidade/etiologia , Inibidores de Fosfolipase A2/química , Fosfolipases A2/química , Caules de Planta/química , Proteínas de Répteis/química , Proteínas de Répteis/metabolismo , Ressonância de Plasmônio de Superfície
3.
Toxicon X ; 7: 100049, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32613196

RESUMO

A bioactive compound isolated from the stem extract of Aristolochia sprucei through High Performance Liquid Chromatography (HPLC) was identified via Nuclear Magnetic Resonance (NMR) as the aristolochic acid (AA). This compound showed an inhibitory effect over the myotoxic activity of Bothrops jararacussu and Bothrops asper venoms, being also effective against the indirect hemolytic activity of B. asper venom. Besides, AA also inhibited the myotoxic activity of BthTX-I and MTX-II with an efficiency greater than 60% against both myotoxins. Docking predictions revealed an interesting mechanism, through which the AA displays an interaction profile consistent with its inhibiting abilities, binding to both active and putative sites of svPLA2. Overall, the present findings indicate that AA may bind to critical regions of myotoxic Asp 49 and Lys49-PLA2s from snake venoms, highlighting the relevance of domains comprising the active and putative sites to inhibit these toxins.

4.
Z Naturforsch C J Biosci ; 75(11-12): 377-387, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-32628640

RESUMO

This study aimed to evaluate the antibacterial and antibiotic-enhancing effects of the essential oil obtained from Ocimum gratissimum L. (OEOg) alone or in association with light-emitting diodes (LED) lights. The essential oil was obtained by hydrodistillation and its chemical composition analysed by gas chromatography coupled to mass spectrometry. The antibacterial and antibiotic-enhancing activities against multiresistant strains of Staphylococcus aureus and Escherichia coli were evaluated by the gaseous contact method. The analysis of the photoinductive effect on the antibacterial activity of the OEOg and antibiotics was assessed through exposure to different LED lights (red, blue and yellow). The phytochemical analysis identified five compounds, including eugenol, as the major constituent. The OEOg caused a significant inhibition of the halo, indicating a direct antibacterial effect. Exposure to the LED lights significantly enhanced the activity of the OEOg against E. coli. On the other hand, the action of the essential oil against S. aureus was enhanced by exposure to both blue and yellow lights. The effects of LED light exposure on the activity of conventional antibiotics varied significantly according to the drug and the bacterial strain. However, most combinations of LED lights and the OEOg presented synergistic effects against resistant bacterial strains, indicating enhanced antibacterial activity. Thus, these in vitro findings suggest that both OEOg and LED lights have promising antibacterial effects. Nevertheless, further research is required to evaluate in vivo the potential of these therapies for the treatment of infectious skin diseases.


Assuntos
Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana/genética , Ocimum/química , Óleos Voláteis/farmacologia , Antibacterianos/farmacologia , Anti-Infecciosos/química , Farmacorresistência Bacteriana/efeitos dos fármacos , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade
5.
J Sci Food Agric ; 99(14): 6199-6208, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31250455

RESUMO

BACKGROUND: The Cerrado occupies 23% of Brazil. A. othonianum is a native Cerrado species that presents differently colored pseudofruits. This report describes the morphometric properties, physicochemical characterization, and phenolic and flavonoid compound compositions of 30 accessions of A. othonianum. RESULTS: The morphometric properties show that an average fruit had 21.97 mm length, 18.61 mm width, and 11.13 mm thickness, with 2.52 g mass. The pseudofruits had 28.84 mm apex width with 12.83 g of mass. The hue parameters of the pseudofruits were 18.67 ± 2.00 and 83.32 ± 1.97° (P < 0.05), reflecting their red to yellow color. The titratable acidity of the accessions was 0.91 ± 0.09 to 3.02 ± 0.02% (P < 0.05), soluble solid content was 9.60 ± 0.17 to 13.47 ± 0.38 °Brix (P < 0.05), and pH ranged from 2.83 ± 0.06 to 3.83 ± 0.06 (P < 0.05). Fourteen flavonoid compounds were identified. The most common compounds in the accessions were vitexin (93% of the accessions), hesperidin (57% of the accessions), epicatechin (34% of the accessions), and kaempferol-3-O-glucoside (30% of the accessions). Cluster analysis generated four groups with the traits ΔE, °h, C, soluble solid content, titratable acidity, pH, total flavonoids, and their identified compounds. CONCLUSIONS: Although all accessions are A. othonianum, there the chemical composition and the physical characteristics of these fruits vary. This is the first report in the literature using wild accessions. Greater disclosure of the species characteristic is interesting because it can increase income for the local population. © 2019 Society of Chemical Industry.


Assuntos
Anacardium/química , Frutas/química , Extratos Vegetais/química , Brasil , Cor , Flavonoides/química , Concentração de Íons de Hidrogênio , Fenóis/química
6.
Chem Biodivers ; 16(1): e1800365, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30371987

RESUMO

This study aimed to isolate and identify flavonoids with hypoglycemic activity in Costus spiralis leaves. The methanolic extract (ME) was rich in flavonoids, while the powdered leaves (PL) contained considerable amounts of macro- and microelements. Oral acute treatment of streptozotocin (STZ)-induced diabetic rats for 18 h with the C. spiralis PL, ME and isolated guaijaverin (GUA) lowered glycemia, improved oral glucose tolerance and inhibited liver lipid peroxidation. GUA and ME lowered plasma levels of low-density and non-high density lipoproteins; GUA also lowered total cholesterol levels. PL, ME and GUA did not significantly alter the plasma levels of triglycerides, high-density lipoproteins, very low-density lipoproteins, creatinine and aspartate transaminase, and the total protein levels in the kidney and liver tissues. Therefore, C. spiralis leaves are promising raw materials and rich sources of bioactive flavonoids for the development of novel antidiabetic drugs due to their hypoglycemic, antidyslipidemic and antioxidant actions.


Assuntos
Glicemia/análise , Costus/química , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Flavonoides/uso terapêutico , Hipoglicemiantes/uso terapêutico , Lipídeos/sangue , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Animais , Antioxidantes/uso terapêutico , Aspartato Aminotransferases/sangue , Creatinina/sangue , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Teste de Tolerância a Glucose , Hipolipemiantes/uso terapêutico , Testes de Função Renal , Testes de Função Hepática , Masculino , Metanol/química , Ratos Wistar , Estreptozocina
7.
Artigo em Inglês | MEDLINE | ID: mdl-23737820

RESUMO

The antihyperglycemic effects of several plant extracts and herbal formulations which are used as antidiabetic formulations have been described and confirmed to date. The main objective of this work was to evaluate the hypoglycemic activity of the aqueous extract of Anacardium humile. Although the treatment of diabetic animals with A. humile did not alter body weight significantly, a reduction of the other evaluated parameters was observed. Animals treated with A. humile did not show variation of insulin levels, possibly triggered by a mechanism of blood glucose reduction. Levels of ALT (alanine aminotransferase) decreased in treated animals, suggesting a protective effect on liver. Levels of cholesterol were also reduced, indicating the efficacy of the extract in reestablishing the balance of nutrients. Moreover, a kidney protection may have been achieved due to the partial reestablishment of blood glucose homeostasis, while no nephrotoxicity could be detected for A. humile. The obtained results demonstrate the effectiveness of A. humile extracts in the treatment of alloxan-induced diabetic rats. Therefore, A. humile aqueous extract, popularly known and used by diabetic patients, induced an improvement in the biochemical parameters evaluated during and following treatment of diabetic rats. Thus, a better characterization of the medicinal potential of this plant will be able to provide a better understanding of its mechanisms of action in these pathological processes.

8.
Pharm Biol ; 50(3): 366-75, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22133075

RESUMO

CONTEXT: Sapindus saponaria L. (Sapindaceae) bark, root, and fruits are used as sedatives and to treat gastric ulcer and also demonstrate diuretic and expectorant effects. OBJECTIVE: The anti-snake venom properties of callus of S. saponaria are investigated here for the first time. MATERIALS AND METHODS: In vitro cultivated callus of Sapindus saponaria were lyophilized, and the extracts were prepared with different solvents, before submitting to phytochemical studies and evaluation of the anti-ophidian activity. Crude extracts were fractionated by liquid-liquid partition and the fractions were monitored by thin layer chromatography (TLC). Subsequently, anti-ophidian activities were analyzed toward Bothrops jararacussu Lacerda (Viperidae), B. moojeni Hoge (Viperidae), B. alternates Duméril (Viperidea) and Crotalus durissus terrificus Lineu (Viperidae) venoms and isolated myotoxins and phospholipase A(2) (PLA(2)). RESULTS: Fractions A1, A2 and the extract in MeOH:H(2)O (9:1) significantly inhibited the toxic and pharmacological activities induced by snake venoms and toxins, when compared to other extracts and fractions. The lethal, clotting, phospholipase, edema-inducing, hemorrhagic and myotoxic activities were partially inhibited by the different extracts and fractions. TLC profiles of the crude extracts (B and C) and fractions (A1 and A2) showed ß-sitosterol and stigmasterol as their main compounds. Stigmasterol exhibited inhibitory effects on enzymatic and myotoxic activities of PLA(2). DISCUSSION AND CONCLUSION: Sapindus saponaria extracts and fractions presented anti-ophidian activity and could be used as an adjuvant to serum therapy or for its supplementation, and in addition, as a rich source of potential inhibitors of enzymes involved in several pathophysiological human and animal diseases.


Assuntos
Antivenenos/farmacologia , Extratos Vegetais/farmacologia , Sapindus/química , Venenos de Víboras/antagonistas & inibidores , Animais , Antivenenos/isolamento & purificação , Bothrops , Cromatografia em Camada Fina , Crotalus , Masculino , Camundongos , Fosfolipases A2/metabolismo , Sitosteroides/isolamento & purificação , Sitosteroides/farmacologia , Estigmasterol/isolamento & purificação , Estigmasterol/farmacologia , Venenos de Víboras/toxicidade
9.
Curr Top Med Chem ; 11(20): 2566-77, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21682680

RESUMO

Four compounds (isoquercitrin, myricetin-3-O-glucoside, catechin and gallocatechin) were isolated from lyophilized aqueous extract of Schizolobium parahyba leaves by chromatography on Sephadex LH-20, followed by semipreparative HPLC using a C-18 column, and identified by 1H and 13C NMR. The compounds were then, tested against hemorrhagic and fibrinogenolytic activities of Bothrops crude venoms and isolated metalloproteinases. The inhibitors neutralized the biological and enzymatic activities of Bothrops venoms and toxins isolated from B. jararacussu and B. neuwiedi venoms. The results showed that gallocatechin and myricetin-3-O-glucoside are good inhibitors of hemorrhagic and fibrinogenolytic activities of metalloproteinases, respectively. Gallocatechin also inhibited the myotoxic activity of both B. alternatus venom and BnSP-6 (Lys49 PhospholipaseA2 from B. neuwiedi). Circular dichroism and docking simulation studies were performed in order to investigate the possible interaction between BnSP-6 and gallocatechin. This is the first time these compounds and their anti-ophidian properties are reported for S. parahyba species. Forthcoming studies involving X-ray co-crystallization, will be of great importance for the development of new therapeutic agents for the treatment of ophidian accidents and for the better understanding of the structure/function relationship of venom toxins.


Assuntos
Antivenenos/farmacologia , Bothrops/fisiologia , Venenos de Crotalídeos/antagonistas & inibidores , Fabaceae/química , Flavonoides/farmacologia , Hemorragia/tratamento farmacológico , Metaloproteases/antagonistas & inibidores , Inibidores de Fosfolipase A2 , Mordeduras de Serpentes , Animais , Antivenenos/química , Antivenenos/isolamento & purificação , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Venenos de Crotalídeos/química , Venenos de Crotalídeos/enzimologia , Venenos de Crotalídeos/isolamento & purificação , Venenos de Crotalídeos/toxicidade , Fibrinolíticos/química , Fibrinolíticos/isolamento & purificação , Fibrinolíticos/toxicidade , Flavonoides/química , Flavonoides/isolamento & purificação , Hemorragia/patologia , Hemorragia/prevenção & controle , Espectroscopia de Ressonância Magnética , Masculino , Metaloproteases/química , Metaloproteases/isolamento & purificação , Metaloproteases/toxicidade , Camundongos , Modelos Moleculares , Músculos/efeitos dos fármacos , Músculos/patologia , Fosfolipases A2/química , Fosfolipases A2/isolamento & purificação , Fosfolipases A2/toxicidade , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta/química
10.
Rev. bras. farmacogn ; 20(4): 519-528, ago.-set. 2010. ilus
Artigo em Inglês | LILACS | ID: lil-557940

RESUMO

The purpose of this study was to investigate the crude extract of Serjania erecta Radlk., Sapindaceae, and its bioactive agents as preventive or inhibitor of memory loss in rodents, as well as other factors correlated with Alzheimer's syndrome: antioxidant and anticholinesterase activity, mainly as plant adaptogen - low toxicity and regulation action. The blocking cholinergic reversion activity (scopolamine) in the test of the passive avoidance was detected by measuring latency in young and adult animals. It presented low toxicity, with protective effect as shown by biochemical analysis (hypoglycemic/hypotriglyceridemic). Elevated levels (above 83 percent) of antioxidant activity were detected. AchE and BuChE inhibition were also detected in the chromatographic fractions, which were active both orally and directly on CNS (ICV).


O objetivo deste estudo foi pesquisar o extrato bruto de Serjania erecta Radlk., Sapindaceae, e seus bioativos como preventivos ou inibidores de perda de memória em roedores, e outros fatores correlacionados com a síndrome de Alzheimer: atividade antioxidante e anticolinesterásicas, principalmente como planta adaptógena, baixa toxicidade e ação regulatória. A reversão do bloqueador colinérgico (escopolamina) no teste da esquiva passiva foi detectada pela latência mensurada em animais jovens e adultos. Apresentou baixa toxicidade, com efeito protetor na análise bioquímica (hipoglicemia/hipotrigliceridemia). Índices elevados (acima 83 por cento) na atividade antioxidante foram observados. A inibição da AChE e BuChE foi perceptível nas frações cromatográficas, confirmando as ações via oral e diretamente no SNC.

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