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1.
J Agric Food Chem ; 69(29): 8081-8089, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34279926

RESUMO

Bryophyllum pinnatum (Lam) Pers. (Crassulaceae) is widely used in folk medicine as leaf juice, aqueous, or hydro-ethanolic extracts. It is also listed as a medicinal plant in several countries such as France and Brazil. The main reported constituents are flavone glycosides, especially those with the rare 3-O-α-l-arabinopyranosyl-(1 → 2)-α-l-rhamnopyranoside moiety. Despite several phytochemical screenings indicating the presence of cyanide derivatives or alkaloids, there are no reports of nitrogenous metabolite characterization from this plant species. Nevertheless, the occurrence and the type of such compounds are of particular interest, as they may account for some of the numerous biological activities and ethnomedicinal uses described for B. pinnatum and could be regarded as chemical/taxonomic markers. Consequently, a hydro-ethanolic extract of B. pinnatum was investigated by using UHPLC-HRMS/MS and the nitrile glucoside sarmentosin was detected for the first time within the genus Bryophyllum/Kalanchoe. Considering the wide use of B. pinnatum and its closely related species for health purposes, the target metabolite was isolated by a combination of centrifugal partition chromatography in elution/extrusion mode and MPLC in order to confirm its structure. A linear, selective, precise, fast, and reliable 1H NMR quantitation method was then developed and validated and may become a tool for easy quality assessment of the plant species. The amount of sarmentosin was determined as 2.07% of the examined sample. Sarmentosin was also detected in Kalanchoe laciniata, confirming the occurrence of this compound within the genus.


Assuntos
Kalanchoe , Brasil , França , Glicosídeos , Nitrilas , Extratos Vegetais , Folhas de Planta , Espectroscopia de Prótons por Ressonância Magnética
2.
Front Microbiol ; 12: 613155, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33692765

RESUMO

Commiphora leptophloeos (Burseraceae) is a medicinal plant native to Brazil which is popularly used for treating oral and vaginal infections. There has been no scientific evidence pointing to its efficacy in the treatment of these infections. Thus, this study sought to investigate the cytotoxic, antifungal, and antibiofilm activity of C. leptophloeos against Candida spp. and to isolate, identify, and quantify the content of B-type oligomeric procyanidins (BDP) in the extract of C. leptophloeos stem bark. The extract and the n-butanol fraction were obtained by maceration and liquid-liquid partition, respectively. Phytochemical analysis performed by HPLC-PDA/ELSD and FIA-ESI-IT-MS/MS allowed the identification and quantification of BDP in the samples. The application of centrifugal partition chromatography helped isolate BDP, which was identified by 1H NMR and MS analyses. Candida spp. reference strains and clinical isolates (including fluconazole-resistant strains) derived from the blood cultures of candidemic patients and the vaginal secretion of patients with vulvovaginal candidiasis were used for evaluating the antifungal and antibiofilm effects. Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) were determined by the microdilution technique, and biofilm inhibition was evaluated through crystal violet and XTT assays. The combined action of BDP with fluconazole was determined by the checkerboard method. The extract, the n-butanol fraction, and the BDP exhibited antifungal activity with MIC values ranging from 312.5 to 2500 µg/mL and were found to significantly reduce the biofilm formed in all the Candida strains investigated. BDP showed a fungicidal potential against strains of Candida spp. (especially against fluconazole-resistant strains), with MIC and MFC values ranging from 156.2 to 2500 µg/mL. In addition, the combined application of BDP and fluconazole produced synergistic antifungal effects against resistant Candida spp. (FICI = 0.31-1.5). The cytotoxic properties of the samples evaluated in human erythrocytes through hemolytic test did not show hemolytic activity under active concentrations. The findings of the study show that C. leptophloeos has antifungal and antibiofilm potential but does not cause toxicity in human erythrocytes. Finally, BDP, which was isolated for the first time in C. leptophloeos, was found to exhibit antifungal effect against Candida spp. either when applied alone or in combination with fluconazole.

3.
J Pharm Biomed Anal ; 193: 113682, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33166841

RESUMO

Bryophyllum pinnatum (Lam.) Oken (Crassulaceae) is widely used as leaf juice or extracts in traditional medicine all over tropical areas, especially in Brazil, to relieve inflammation-associated symptoms. Flavonol glycosides with unusual sugar moiety are among the major metabolites. Nevertheless, there are not enough quality control studies that can contribute to authentication of B. pinnatum and determination of their markers. As it is also used as medicinal plant in several countries, it is necessary to provide data related to safety, efficacy and quality. In this context, this work aims to isolate the major flavonoids from B. pinnatum hydroethanolic extract, to validate a method to quantify the content of chemical markers and to evaluate their xanthine oxidase inhibition and antioxidant activity. The extract was submitted to centrifugal partition chromatography (CPC). The solvents system CyHex-EtOAc-EtOH-H2O, 0.5:9:3:5.5, v/v/v/v was selected by shake-flask method. Four flavonoids (quercetin 3-O-α-L-arabinopyranosyl-(1→2)-O-α-L-rhamnopyranoside (1), kaempferol 3-O-α-L-arabinopyranosyl-(1→2)-O-α-L-rhamnopyranoside (2), quercetin 3-O-α-L-rhamnopyranoside (3) and kaempferol 3-O-α-L-rhamnopyranoside (4)) were isolated in a single and fast CPC run and their structures were confirmed by NMR analysis. An UPLC-DAD quantification method was established for the first time with validation of required parameters, according to RDC 166/2017. The calibration curves were linear with correlation coefficient ranging from 0.9996 to 0.9997 while the values of LOD (0.0077-1.984 ng.mL-1), LOQ (0.0263-6.012 ng.mL-1), recovery (≥ 80.7 %) and inter-day (%RSD ≤ 3.581) and intra-day precision (%RSD ≤ 2.628) were satisfactory. Quantitative analysis of these compounds showed that the proportion of 1, 2 and 3 were 2.43, 0.25 and 0.33 % (24.3 mg.g-1, 0.25 mg.g-1 and 0.33 mg.g-1 of extract), respectively. Moreover, in vitro xanthine oxidase (XO), DPPH and ABTS inhibition were evaluated for the extract and the major flavonoids. Compounds 2 (168 µM) and 3 (124 µM) moderately inhibited XO, while compounds 1 and 3 displayed average radical scavenging activity. In conclusion, our results suggest the flavonoid 1 as a specific marker which may be used for quality control of B. pinnatum hydroethanolic leaves extract.


Assuntos
Kalanchoe , Brasil , Flavonoides , Extratos Vegetais/farmacologia , Folhas de Planta
4.
Pharm Biol ; 58(1): 490-497, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32478640

RESUMO

Context: Mitrephora sirikitiae Weeras., Chalermglin & R.M.K. Saunders (Annonaceae) is a plant endemic to Thailand. Its constituents and their biological activities are unknown.Objective: Isolation and identification of the compounds in the leaves and stems of M. sirikitiae and determination of their cytotoxicity.Materials and methods: Methanol extracts of the leaves and stems of M. sirikitiae were separated by chromatography, and spectroscopic methods were used to determine the structures of the components. The cytotoxicity of the extracts and pure compounds was evaluated using the sulforhodamine B assay with several cell lines. The cells were treated with the compounds at concentrations of 0.16-20 µg/mL for 48 or 72 h.Results: The investigation of the extracts of M. sirikitiae leaves and stems resulted in the isolation of a new lignan, mitrephoran, and 15 known compounds. Among these compounds, 2-(3,4-dimethoxyphenyl)-6-(3,5-dimethoxyphenyl)-3,7-dioxabicyclo[3.3.0]octane, ciliaric acid, 6-methoxymarcanine A, and stepharanine were isolated from this genus for the first time. The alkaloids liriodenine and oxoputerine exhibited strong cytotoxicity against all tested cells (IC50 values of 6.59-11.02 µM). In contrast, magnone A, 3',4-O-dimethylcedrusin, and 6-methoxymarcanine A inhibited the growth of some of the tested cells (IC50 values of 2.03-19.73 µM). Magnone A and 6-methoxymarcanine A showed low toxicity for Hek 293 cells (IC50 >20 µM).Discussion and conclusions: M. sirikitiae is a source of cytotoxic lignans and alkaloids. Among the cytotoxic compounds, magnone A and 6-methoxymarcanine A are potentially useful lead compounds for the further development of anticancer agents because of their selective inhibitory effects on cancer cell lines.


Assuntos
Annonaceae , Antineoplásicos Fitogênicos/toxicidade , Citotoxinas/toxicidade , Extratos Vegetais/toxicidade , Folhas de Planta , Células A549 , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Citotoxinas/isolamento & purificação , Relação Dose-Resposta a Droga , Células HEK293 , Células HT29 , Humanos , Células MCF-7 , Extratos Vegetais/isolamento & purificação , Ratos , Espectrometria de Massas por Ionização por Electrospray/métodos , Tailândia
5.
Toxicon ; 172: 53-60, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31704310

RESUMO

"Chiniy-tref" (CT) is a traditional preparation used in folk medicine in Martinique Island (French West Indies) that is nowadays mainly taken orally to prevent or act against any "manifestation of evil". CT is easily prepared at home by macerating larvae of the endemic swallowtail Battus polydamas (ssp.) cebriones (Dalman, 1823), sometimes accompanied by a leaf of its host-plant Aristolochia trilobata L., in commercial rum. We have previously reported the detection of nephrotoxic and carcinogenic aristolochic acids (AAs) I and II in CT, leading the Regional Health Agency (ARS) of Martinique to issue an alert regarding the potential risks associated with its consumption in 2015. In order to complete the toxicity risk assessment for oral consumption of CT, a full qualitative analysis of AAs and their analogues (AAAs) was performed, as well as a quantitative determination of the major AAs, namely AAs I and II. The phytochemical profiling of AAAs present in CT, that also corresponds to that of B. polydamas cebriones larvae feeding on A. trilobata, has been established for the first time by ultra-high performance liquid chromatography/electrospray ionization quadrupole time of-flight tandem mass spectrometry. AAs I and II were quantified in a small panel of tinctures by using a validated UHPLC/UV method, allowing us to estimate the probable daily intakes of these toxins by CT consumers. The results proved the existence of a real risk of renal toxicity and carcinogenicity associated with the chronic oral consumption of CT in Martinique, and more generally of similar "snake bottles" throughout the Caribbean.


Assuntos
Aristolochia/química , Ácidos Aristolóquicos/análise , Borboletas/química , Medicina Tradicional , Animais , Ácidos Aristolóquicos/química , Larva/química , Martinica , Toxinas Biológicas/análise , Toxinas Biológicas/química
6.
J Ethnopharmacol ; 231: 217-229, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30412750

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Previous ethnobotanical surveys from the north Andean part of Chile, where different ethnic groups are co-existing, with the preeminence of Aymara and Atacama traditions, revealed an extensive domestic use of the local flora. In these communities, traditional medicinal uses are mainly related to the treatment of respiratory, gastro-intestinal and urinary disorders, pain and inflammation, which is closely linked to epidemiological observations. AIM OF THE STUDY: As these symptoms may be related to infectious diseases, a bioguided evaluation of antibacterial and antifungal activity was conducted on eighteen species selected with the Taira community, in Ollague. MATERIALS AND METHODS: Screening was performed using a large panel of pathogenic germs involved in the main community acquired infectious diseases, represented by Gram positive and Gram negative bacteria of clinical interest and by human pathogenic fungi, using a bioguided approach. RESULTS AND CONCLUSIONS: Gram positive strains of clinical interest were highly sensitive to Aloysia deserticola (Verbenaceae) and Krameria lappacea (Krameriaceae) extracts. The bioguided approach led us to identify the isolated neolignan from K. lappacea conocarpan (1), and triterpenoids form A. deserticola (oleanolic acid (6) and ursolic acid (10)), as the main bioactive compounds.


Assuntos
Anti-Infecciosos/farmacologia , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Lignanas/farmacologia , Magnoliopsida , Triterpenos/farmacologia , Chile , Fungos/crescimento & desenvolvimento , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Medicina Tradicional , Plantas Medicinais
7.
Sci Rep ; 8(1): 13520, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30202067

RESUMO

Tinospora crispa is a popular traditional herbal plant commonly used throughout the world for treatment of various diseases, in particular type 2 diabetes mellitus. We report here a new case of toxic hepatitis in a 57-year old male patient in the French West Indies following the consumption of two aqueous extracts of fresh Tinospora crispa stems. It thus differs from two previously reported cases that concerned the chronic intake of powdered dry stems delivered in solid oral dosage forms (i.e. pellets and tablets). Liquid Chromatography-Diode Array Detection-Mass Spectrometry (LC/DAD/MS) analyses were performed on an aqueous extract of the offending sample that mimics the swallowed preparation. They revealed the presence of species-specific molecular marker borapetoside C (1) and thus enabled an unambiguous phytochemical identification. The exploration of tandem MS/MS data obtained by ultra-high performance liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry (UHPLC-ESI-QTOF-HRMS) allowed the identification of 17 additional cis-clerodane-type furanoditerpenoid lactones, analogues of 1. These results support the hypothesis that the mechanisms underlying hepatotoxicity of Tinospora crispa are the same as those encountered with furanoditerpenoids-containing plants such as Teucrium chamaedrys or Dioscorea bulbifera. In the context of type 2 diabetes treatment, we recommend that Tinospora crispa intake should be more closely monitored for signs of hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Diterpenos Clerodânicos/toxicidade , Extratos Vegetais/efeitos adversos , Tinospora/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Caules de Planta/química , Caules de Planta/toxicidade , Tinospora/química
8.
J Chromatogr A ; 1513: 149-156, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28754247

RESUMO

A purification sequence including a Gilson CPC 250 PRO device coupled to PrepHPLC hyphenated with a MS triggering fraction collector was applied to isolate secoiridoid glycosides from a complex methanolic extract of Centaurium erythraea. This species is widely used for ethnomedicinal purposes around the Mediterranean Sea. The solvent system ethyle acetate/ethanol/water 7.5/3/5 was determined using shake-flask method targeting swertiamarin, the major secoiridoid of the extract. Optimization of CPC experimental parameters enabled the injection of 4g of extract with a flow rate of 40mL/min at 3000rpm to provide a secoiridoid glycosides enriched fraction. 130mg of this latter was submitted to a second step of purification by preparative HPLC (gradient water/formic acid (19:1) (A) and methanol (B) as follows: 0min, 85% A; 8min, 60% A; 12min, 55% A; 35min, 55% A; 40min, 10% A; 50min, 10% A; 52min, 85% A; 55min, 85% A) to give swertiamarin (36mg, yield 27.7%, purity 98.2%). Other secoiridoid glycosides (sweroside, gentiopicroside, secologanol, secoxyloganin) were also isolated in minor amounts. As these monoterpene derivatives are responsible for several biological activities, their quick recovery with high yield and purity may serve as a model for further scale-up and industrial development.


Assuntos
Centaurium/química , Centrifugação/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Glicosídeos Iridoides/análise , Espectrometria de Massas/métodos , Glicosídeos Iridoides/química , Glicosídeos Iridoides/isolamento & purificação , Mar Mediterrâneo , Metanol/química , Extratos Vegetais/química , Solventes/química , Raios Ultravioleta
9.
Fitoterapia ; 118: 1-5, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28167052

RESUMO

A heme-binding assay based on mass spectrometry was performed on P. monodiana Maire (Asteraceae) extracts to identify metabolites able to form adducts with heminic part of haemoglobin, as potential antimalarial drugs. Main adducts were characterized and their stability was measured. Isolation of main constituents of P. monodiana Maire lead to identification of the two methoxyflavones 3'-O-methyleupatorin (7) and artemetin (8) involved in the adducts formation. Four seco-tanapartholides (1-4), a guaianolide (5), a germacranolide (6) and two other methoxyflavones (9, 10) were also characterized. Evaluation of isolated compounds on P. falciparum and T. brucei brucei showed a moderate antiprotozoal activity of the two methoxyflavones.


Assuntos
Antiprotozoários/química , Asteraceae/química , Flavonas/química , Hemoglobinas/química , Argélia , Antiprotozoários/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Flavonas/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Espectrometria de Massas , Estrutura Molecular , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Plasmodium falciparum/efeitos dos fármacos , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/isolamento & purificação , Trypanosoma brucei brucei/efeitos dos fármacos
10.
Planta Med ; 81(17): 1604-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26393938

RESUMO

The aim of this study was to investigate the species Symphonia globulifera, a source of polycyclic polyprenylated acyl phloroglucinols such as guttiferone A, which is known to exhibit a variety of biological activities including noticeable antileishmanial properties. Our goal was the identification and the quantification of guttiferone A in different renewable parts of S. globulifera and its preparative isolation. To the best of our knowledge, there is no data concerning its mechanism of action. Consequently, it is particularly interesting to isolate it in gram quantities in order to establish structure activity relationship studies. After performing high-performance liquid chromatography profiles detecting the presence of guttiferone A and proceeding to its quantification, a centrifugal partition chromatography methodology using a two-phase solvent system of cyclohexane/ethyl acetate/methanol/water (20 :  1 :  20 : 1, v/v/v/v) was applied to each extract. In conclusion, a centrifugal partition chromatography system has been developed to ensure a fast, reliable, and scalable way to isolate, with a high level of purity, guttiferone A from five renewable parts of S. globulifera. Moreover, this methodology can be extended to the isolation of other polycyclic polyprenylated acyl phloroglucinols such as guttiferones B, C, and D.


Assuntos
Benzofenonas/isolamento & purificação , Centrifugação com Gradiente de Concentração/métodos , Clusiaceae/química , Benzofenonas/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular
11.
J Mass Spectrom ; 50(3): 495-512, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25800186

RESUMO

Acronychia-type acetophenones (AtA) is a chemical group of compounds of important structural and biological interest, abundant in Acronychia species. However, there are no data available for their characterization using mass spectrometry. In the current work, AtA have been investigated by multistage high resolution mass spectrometry and both electrospray ionization and atmospheric pressure chemical ionization, in positive and negative mode, were utilized for their structure elucidation and identification. The analysis of AtA using a linear ion trap-Orbitrap analyzer enabled the structural determination of key fragment ions and cleavages, which can be used for the structural characterization thereof. A systematic nomenclature based on protonated and deprotonated fragment ions under collision-induced dissociation conditions and decision trees for the structural determination of AtA are proposed. Furthermore, taking advantage of the characteristic fragmentation patterns, a selective Ultra High Performance Liquid Chromatography Electrospray Ionization multistage Mass Spectrometry (UHPLC-ESI(-)-MS(n)) method was developed and successfully applied for the dereplication of known AtA and the identification of potentially new ones in Acronychia extracts. Despite the structure similarity and the presence of isomers, accurate characterization of known and unknown AtA derivatives was possible.


Assuntos
Acetofenonas/análise , Acetofenonas/química , Cromatografia Líquida/métodos , Rutaceae/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Íons/análise , Íons/química , Modelos Moleculares , Casca de Planta/química , Extratos Vegetais/química
12.
Eur J Med Chem ; 93: 93-100, 2015 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-25659770

RESUMO

A series of 16 flavonoids were isolated and prepared from bud exudate of Gardenia urvillei and Gardenia oudiepe, endemic to New Caledonia. Most of them are rare polymethoxylated flavones. Some of these compounds showed noticeable activity against Leishmania (Leishmania) amazonensis, Plasmodium falciparum and Trypanosoma brucei gambiense, in addition to tubulin polymerization inhibition at low micromolar concentration. We also provide a full set of NMR data as some of the flavones were incompletely described.


Assuntos
Inibidores da Angiogênese/farmacologia , Antiparasitários/farmacologia , Flavonoides/farmacologia , Gardenia/química , Extratos Vegetais/química , Inibidores da Angiogênese/síntese química , Inibidores da Angiogênese/química , Inibidores da Angiogênese/isolamento & purificação , Animais , Antiparasitários/síntese química , Antiparasitários/química , Antiparasitários/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desenho de Fármacos , Flavonoides/síntese química , Flavonoides/química , Flavonoides/isolamento & purificação , Flores/química , Humanos , Leishmania/efeitos dos fármacos , Estrutura Molecular , Nova Caledônia , Plasmodium falciparum/efeitos dos fármacos , Relação Estrutura-Atividade , Trypanosoma brucei gambiense/efeitos dos fármacos
13.
Nat Prod Res ; 29(19): 1820-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25665945

RESUMO

A new 3,4-seco-cycloartane, identified as (24R,25S)-dihydroxy-26-O-nonadecylcarbonyloxy-3,4-secocycloarta-4(28)-en-3-oic acid (1), has been isolated from the leaves of Hopea odorata Roxb. (Dipterocarpaceae), together with the rare 3,4-seco-cycloart-4(28),24-diene-3,26-dioic acid (2 or abiesatrine J) and six other known compounds (3-8). Their structures were elucidated on the basis of both chemical and spectroscopic methods.


Assuntos
Dipterocarpaceae/química , Folhas de Planta/química , Triterpenos/química , Estrutura Molecular , Plantas Medicinais/química , Secoesteroides/química , Secoesteroides/isolamento & purificação , Tailândia , Triterpenos/isolamento & purificação
14.
Planta Med ; 81(2): 95-107, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25590372

RESUMO

Symphonia globulifera has been widely used in traditional medicine and has therefore been subjected to several phytochemical studies in the American and African continents. Interestingly, some disparities have been observed concerning its metabolic profile. Several phytochemical studies of S. globulifera have led to the identification of more than 40 compounds, including several polycyclic polyprenylated acylphloroglucinols. Biological evaluations have pointed out the promising biological activities of these secondary metabolites, mostly as antiparasitic or antimicrobial, confirming the traditional use of this plant. The purpose of this review is to describe the natural occurrence, botanical aspects, ethnomedicinal use, structure, and biogenesis, as well as biological activities of compounds isolated from this species according to their provenance.


Assuntos
Anti-Infecciosos/farmacologia , Clusiaceae/química , Extratos Vegetais/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Vias Biossintéticas , Medicina Tradicional , Metabolômica , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Metabolismo Secundário
15.
Molecules ; 19(4): 4369-79, 2014 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-24722590

RESUMO

Genista species are sources of antioxidant phenolic compounds such as O- and C-glycosylflavonoids and isoflavonoids. A combination of a DPPH scavenging assay with HPTLC-MS, a fast and efficient method for identification of bioactive compounds, has been applied for evaluation of the radical scavenging activity of metabolites from Genista saharae Coss. & Dur. Different organs collected at various periods have been compared. Identification of antioxidant compounds was obtained by elution of the major DPPH-inhibition zones. The resulting HPTLC-MS analysis under moderately polar conditions, coupled to the DPPH results led to the putative identification of two antioxidant isoflavone aglycones: 3',4',5,7-tetrahydroxyisoflavone (1) and ficuisoflavone (3), whereas polar migration conditions led to the identification of the glycosides 5-methoxy-4',7-trihydroxy-8-glucopyranosylisoflavone (4) and 4',5-dihydroxy-7-methoxyisoflavone-4'-O-ß-D-gluco-pyranoside (5). Evaluation of percentage of inhibition of DPPH radical by the purified isoflavone 4 from the root extract showed that it affords a moderate contribution to the total radical scavenging activity of the extract.


Assuntos
Compostos de Bifenilo/antagonistas & inibidores , Sequestradores de Radicais Livres/química , Genista/química , Glicosídeos/química , Isoflavonas/química , Picratos/antagonistas & inibidores , Cromatografia em Camada Fina/métodos , Sequestradores de Radicais Livres/isolamento & purificação , Glicosídeos/isolamento & purificação , Isoflavonas/isolamento & purificação , Espectrometria de Massas , Extratos Vegetais/química , Raízes de Plantas/química
16.
J Nat Prod ; 77(3): 441-5, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24568174

RESUMO

The dialdehydes oleacein (2) and oleocanthal (4) are closely related to oleuropein (1) and ligstroside (3), the two latter compounds being abundant iridoids of Olea europaea. By exploiting oleuropein isolated from the plant leaf extract, an efficient procedure has been developed for a one-step semisynthesis of oleacein under Krapcho decarbomethoxylation conditions. Highlighted is the fact that 5-lipoxygenase is a direct target for oleacein with an inhibitory potential (IC50: 2 µM) more potent than oleocanthal (4) and oleuropein (1). This enzyme catalyzes the initial steps in the biosynthesis of pro-inflammatory leukotrienes. Taken together, the methodology presented here offers an alternative solution to isolation or total synthesis for the procurement of oleacein, thus facilitating the further development as a potential anti-inflammatory agent.


Assuntos
Aldeídos/síntese química , Aldeídos/isolamento & purificação , Anti-Inflamatórios/síntese química , Araquidonato 5-Lipoxigenase/metabolismo , Inibidores de Lipoxigenase/farmacologia , Olea/química , Fenóis/síntese química , Fenóis/isolamento & purificação , Aldeídos/química , Aldeídos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Monoterpenos Ciclopentânicos , Glucosídeos/metabolismo , Humanos , Glucosídeos Iridoides , Iridoides/análise , Iridoides/metabolismo , Estrutura Molecular , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/metabolismo , Piranos/metabolismo
17.
Fitoterapia ; 85: 49-56, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23305777

RESUMO

From the leaves of Miliusa mollis Pierre (Annonaceae), five new dihydrobenzofuran neolignans, namely miliumollin, 7-methoxymiliumollin, 3'-methoxymiliumollin, 4'-O-methylmiliumollin and miliumollinone, and a new 8-O-4' neolignan named miliusamollin were isolated, and their structures were elucidated through analysis of spectroscopic data. Miliumollin, 3'-methoxymiliumollin, miliumollinone and decurrenal exhibited weak cytotoxicity against KB, MCF7 and NCI-H187 cells. Miliumollinone possessed weak inhibitory effects against herpes simplex virus types 1 and 2. None of the isolates displayed inhibitory activity against avian influenza H5N1 neuraminidase.


Assuntos
Annonaceae/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antivirais/isolamento & purificação , Lignanas/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Testes de Sensibilidade Microbiana , Estrutura Molecular , Folhas de Planta/química
18.
Nat Prod Res ; 27(2): 137-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22493952

RESUMO

A new pentacyclic triterpenoid and three new derivatives based on the taraxer-14-ene skeleton with a C-28 attached a carboxylic acid group have been isolated from the stem bark of Hypodaphnis zenkeri, together with six known compounds. The new product was identified as 2α,3α-dihydroxytaraxer-14-en-28-oic acid (1). Its derivatives, 2α,3α-diacetyltaraxer-14-en-28-oic acid (2), 2α,3α-di-O-carbonyl-2α,3α-dihydroxytaraxer-14-en-28-oic acid (3) and 2α,3α-dipropionyltaraxer-14-en-28-oic acid (4) were obtained by semisynthesis. The known compounds were identified as 3ß-hydroxytaraxer-14-en-28-oic acid or aleuritolic acid (5) (McPhail, A.T., McPhail, D.R., Wani, M.C., Wall, M.E. & A.W., Nicholas, A.W. (1989). Identity of maprounic acid with aleuritolic acid. Revision of the structure of maprounic acid: X-ray crystal structure of p-bromobenzyl acetylmaprounate. Journal Natural Products, 52, 212), 3α-hydroxytaraxer-14-en-28-oic acid or isoaleuritolic acid (6), 3α-acetyltaraxer-14-en-28-oic acid acetate or aleuritolic acid acetate (7) (Chaudhuri, S.K., Fullas, F., Brown, D.M., Wani, M.C., Wall, M.E., Cai, L., … Kinghorn, A.D. (1995). Isolation and structural elucidation of pentacyclic triterpenoids from Maprounea africana. Journal of Natural Products, 58, 1-9), 3-oxo-taraxer-14-ene or taraxerone (8) ß-sitosterol (9) and stigmasterol (10) (Kamboj & Saluja, 2011), together with fatty acids. Their structures were established on the basis of spectroscopic studies and chemical transformations.


Assuntos
Lauraceae/química , Casca de Planta/química , Extratos Vegetais/análise , Triterpenos/análise , Cristalografia por Raios X , Metanol , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Triterpenos/isolamento & purificação
19.
Chem Pharm Bull (Tokyo) ; 60(8): 1072-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22863713

RESUMO

From the methanol extract of the stem bark of Ficus exasperata, a new sphingolipid named Ficusamide, (2S,3S,4R,11E)-2-[(2',3'-dihydroxyhexacosanoylamino)]-11-octadecene-1,3,4-triol (1), along with three known furanocoumarins, (S)-(-) oxypeucedanin hydrate (2), (R)-(+) oxypeucedanin hydrate (3), bergapten (5-methoxypsoralen) and six other known compounds, were isolated. Their structures were characterized basing on spectroscopic methods and chemical evidence. Compounds (1-3) were analyzed for their antimicrobial activity. Ficusamide (1) showed wick activity (minimal inhibitory concentration (MIC)=312.5 µg/mL) against Escherichia coli, while the furanocoumarins (2) and (3) showed significant activity (MIC=9.76 µg/mL) against Bacillus cereus, Candida albicans and Microsporum audouinii.


Assuntos
Ficus/química , Furocumarinas/farmacologia , Esfingolipídeos/farmacologia , Bacillus cereus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Furocumarinas/química , Furocumarinas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Microsporum/efeitos dos fármacos , Estrutura Molecular , Casca de Planta/química , Extratos Vegetais/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Esfingolipídeos/química , Esfingolipídeos/isolamento & purificação
20.
Nat Prod Commun ; 7(7): 891-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22908574

RESUMO

A series of 3,3-dimethyl-3Hbenzothieno[3,2-f][1]-benzopyran analogues modified at the pyran 1,2-double bond were synthesized. The corresponding dihydro and (+/-)-cis-diol derivatives were converted into diacetate and cyclic carbonate upon acylation. The title compounds were characterized by spectroscopic analysis and screened for their antimicrobial activity in vitro.


Assuntos
Anti-Infecciosos/síntese química , Anti-Infecciosos/farmacologia , Benzopiranos/síntese química , Benzopiranos/farmacologia , Enxofre/química , Anti-Infecciosos/química , Benzopiranos/química , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular
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