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1.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361759

RESUMO

Croton ferrugineus Kunth is an endemic species of Ecuador used in traditional medicine both for wound healing and as an antiseptic. In this study, fresh Croton ferrugineus leaves were collected and subjected to hydrodistillation for extraction of the essential oil. The chemical composition of the essential oil was determined by gas chromatography equipped with a flame ionization detector and gas chromatography coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against three Gram-positive bacteria, one Gram-negative bacterium and one dermatophyte fungus. The radical scavenging properties of the essential oil was evaluated by means of DPPH and ABTS assays. The chemical analysis allowed us to identify thirty-five compounds representing more than 99.95% of the total composition. Aliphatic sesquiterpene hydrocarbon trans-caryophyllene was the main constituent with 20.47 ± 1.25%. Other main compounds were myrcene (11.47 ± 1.56%), ß-phellandrene (10.55 ± 0.02%), germacrene D (7.60 ± 0.60%), and α-humulene (5.49 ± 0.38%). The essential oil from Croton ferrugineus presented moderate activity against Candida albicans (ATCC 10231) with an MIC of 1000 µg/mL, a scavenging capacity SC50 of 901 ± 20 µg/mL with the ABTS method, and very strong antiglucosidase activity with an IC50 of 146 ± 20 µg/mL.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Croton/química , Inibidores Enzimáticos/química , Óleos Voláteis/química , Folhas de Planta/química , Monoterpenos Acíclicos/química , Monoterpenos Acíclicos/isolamento & purificação , Alcenos/química , Alcenos/isolamento & purificação , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Benzotiazóis/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Monoterpenos Cicloexânicos/química , Monoterpenos Cicloexânicos/isolamento & purificação , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Sesquiterpenos Monocíclicos/química , Sesquiterpenos Monocíclicos/isolamento & purificação , Picratos/antagonistas & inibidores , Sesquiterpenos Policíclicos/química , Sesquiterpenos Policíclicos/isolamento & purificação , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/isolamento & purificação , Ácidos Sulfônicos/antagonistas & inibidores , alfa-Glucosidases/química
2.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361766

RESUMO

Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography-gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the principal constituent in male (28.24 and 25.90%) and female (26.47 and 23.90%) essential oil. Other main compounds were methyl chavicol, germacrene D, methyl eugenol, and α-pinene. Female essential oil presented a strong activity against Klebsiella pneumoniae (ATCC 9997) with an minimum inhibitory concentration (MIC) of 500 µg/mL and a scavenging capacity SC50 of 800 µg/mL.


Assuntos
Antibacterianos/química , Antioxidantes/química , Monoterpenos Cicloexânicos/química , Magnoliopsida/química , Óleos Voláteis/química , Derivados de Alilbenzenos/química , Derivados de Alilbenzenos/isolamento & purificação , Anisóis/química , Anisóis/isolamento & purificação , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Arthrodermataceae/efeitos dos fármacos , Arthrodermataceae/crescimento & desenvolvimento , Benzotiazóis/antagonistas & inibidores , Monoterpenos Bicíclicos/química , Monoterpenos Bicíclicos/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Monoterpenos Cicloexânicos/isolamento & purificação , Equador , Eugenol/análogos & derivados , Eugenol/química , Eugenol/isolamento & purificação , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Magnoliopsida/metabolismo , Masculino , Testes de Sensibilidade Microbiana , Picratos/antagonistas & inibidores , Folhas de Planta/química , Plantas Medicinais , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/isolamento & purificação , Fatores Sexuais , Ácidos Sulfônicos/antagonistas & inibidores
3.
Chem Biodivers ; 18(8): e2100260, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34139055

RESUMO

The phytochemistry of Cynophalla mollis (Kunth) J. Presl and Colicodendron scabridum (Kunth), both belonging to the family Capparaceae, were investigated in this study for the first time. Lupeol, betulin, lutein, stachydrine and quercetin-3,4'-di-O-rhamnoside were isolated from C. mollis, whereas C. scabridum afforded lupeol, lutein, stachydrine, ß-sitosterol, stigmasterol, betonicine and narcissoside. All these compounds were purified by preparative liquid chromatography, in both open column and instrumental (MPLC) separation systems. Preparative TLC was also applied. They were all identified by 1 H- and 13 C-NMR experiments. The complete structure of the very rare flavonoid quercetin-3,4'-di-O-rhamnoside was fully elucidated through DEPT-135, COSY, HMQC and HMBC experiments, together with UV/VIS and FT-IR spectrophotometry. Complete NMR data for quercetin-3,4'-di-O-rhamnoside in deuterated methanol were presented here for the first time. All the extracts did not exert antioxidant activity at the maximum tested dose of 1 mg/mL. Three out of the nine isolated compounds exerted a good spectrum of antioxidant capacity, being narcissoside the most active against ABTS radicals, with SC50 =12.43 µM. It was followed by lutein and quercetin-3,4'-di-O-rhamnoside, with 40.92 µM and 46.10 µM, respectively.


Assuntos
Capparaceae/química , Flavonoides/química , Sequestradores de Radicais Livres/química , Quercetina/química , Capparaceae/metabolismo , Equador , Flavonoides/isolamento & purificação , Sequestradores de Radicais Livres/isolamento & purificação , Espectroscopia de Ressonância Magnética , Conformação Molecular , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Quercetina/isolamento & purificação
4.
Plants (Basel) ; 10(2)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578706

RESUMO

Piper carpunya Ruiz & Pav. is an aromatic shrub native to Ecuador, the leaves of which are used to prepare the traditional beverage Guaviduca. Different health benefits are attributed to the guaviduca beverage, which is consumed as a traditional and folk medicine. In this study, fresh P. carpunya leaves were collected in the winter and summer and subjected to hydrodistillation for the extraction of the essential oil. The guaviduca beverage was prepared by infusion in water and the volatile compounds were isolated by liquid-liquid extraction. Chemical composition and enantioselective analyses were performed by gas chromatography. The antibacterial activity was assayed against Gram-positive and Gram-negative bacteria. The scavenging radical properties of the essential oil was evaluated by 2,2-diphenyl-1-picrylhydryl (DPPH) and 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. The acetylcholinesterase inhibitory activity was measured using the spectrophotometric method. The chemical analysis allowed us to identify more than 98% of the compounds in all samples. The main constituent of the essential oil was 1,8-cineole (25.20 ± 1.31%) in P. carpunya collected in winter and (17.45 ± 2.33%) in P. carpunya collected in summer, while in the beverage, there was 14 mg/L. Safrole was identified in the essential oil (PCW 21.91 ± 2.79%; PCS 13.18 ± 1.72%) as well as in the beverage (2.43 ± 0.12 mg/L). Enantioselective analysis was used to investigate the enantiomeric ratio and excess of four chiral components. The essential oil presented a strong activity against Klebsiella pneumoniae with a MIC of 500 µg/mL and a very strong anticholinesterase activity with an IC50 of 36.42 ± 1.15 µg/mL.

5.
Plants (Basel) ; 9(12)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33256174

RESUMO

Essential oils are highly demanded substances worldwide. They can be used without modification due to their different chemical and biological properties or as natural sources of chemical compounds. The limit in the use of these metabolites is their low yield. In the present investigation, the essential oil of fruits from Dacryodes peruviana collected in the Ecuadorian Amazon was extracted and studied. The essential oil was released from the plant matrix and isolated by hydrodistillation. The yields obtained were 4.8 ± 0.2% and 11.3 ± 0.2% for fresh and dried fruits, respectively, one of the highest yields on record to date. Twenty-five chemical compounds were identified by GC/MS and GC/FID techniques. The principal constituent was α-phellandrene, with 50.32 ± 3.32%. The antimicrobial activity of the oil was assayed against five Gram negative bacteria, two Gram positive bacteria and two fungi. The essential oil exerted a moderate activity against Staphylococcus aureus. The repellent activity of the oil was assayed against mosquitoes (Diptera: Culicidae); the samples with 3%, 2% and 1% essential oil were class 4, and the sample with 0.5% showed to be class 3. The essential oil showed a weak antioxidant activity through the DPPH and ABTS methods.

6.
Nat Prod Res ; : 1-6, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32851854

RESUMO

In the present research, the essential oil from Piper ecuadorense was analysed by GC/MS and GC/FID techniques. A total of forty-four chemical compounds were identified which represent 98.65% of the essential oil composition. The main compounds were bicyclogermacrene (12.98%), 3-thujopsanone (11.59%), α-phellandrene (6.89%), (E)-nerolidol (6.88%), δ-elemene (6.83%) and shyobunol (5.79%). The essential oil from P. ecuadorense exerted a strong activity against Gram-positive bacterium Staphylococcus aureus (ATCC 25923) with an MIC of 250 µg/mL, and a very strong activity against Trichophyton rubrum (ATCC 28188) and Trichophyton mentagrophytes (ATCC 28185) with an MIC of 62.5 µg/mL in both cases. The antioxidant activity of essential oil was explored using DPPH and ABTS method, through ABTS assay. The oils showed an IC50 of 1.81 ± 0.09 mg/mL. This is the first report on the chemical composition and biological activity of essential oil from this species.

7.
Microorganisms ; 8(5)2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32466301

RESUMO

Naegleria fowleri is an opportunistic pathogenic free-living amoeba which is able to rapidly colonize the central nervous system (CNS) and causes a lethal infection known as primary amoebic meningoencephalitis (PAM). Furthermore, more than 98% of the known cases of PAM are fatal and affect mainly children under 12 and young adults. Until now, no fully effective therapeutic agents against N. fowleri are available and hence the urgent need to find novel agents to treat PAM. At present, PAM therapy is based on the combination of amphotericin B, miltefosine, among others, with unwanted toxic effects. Recently, our team isolated various indolocarbazoles (ICZs) from the culture of a mangrove strain of Streptomyces sanyensis which showed activity against kinetoplastids and the Acanthamoeba genus. Hence, in this study, the activity of the previously isolated ICZs, staurosporine (STS), 7-oxostaurosporine (7OSTS), 4'-demethylamino-4'-oxostaurosporine, and streptocarbazole B, was evaluated against two type strains of N. fowleri. Furthermore, the performed activity assays revealed that STS was the most active ICZ presenting an inhibitory concentration 50 (IC50) of 0.08 ± 0.02 µM (SI 109.3). Moreover, STS induced programmed cell death (PCD) in the treated amoebae by triggering DNA condensation, mitochondrial disfunction, cell membrane disruption, and reactive oxygen species (ROS) generation. Therefore, STS could be a promising therapeutic agent against PAM.

8.
Biomolecules ; 10(4)2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32344693

RESUMO

Chagas disease and leishmaniasis are neglected tropical diseases caused by kinetoplastid parasites of Trypanosoma and Leishmania genera that affect poor and remote populations in developing countries. These parasites share similar complex life cycles and modes of infection. It has been demonstrated that the particular group of phosphorylating enzymes, protein kinases (PKs), are essential for the infective mechanisms and for parasite survival. The natural indolocarbazole staurosporine (STS, 1) has been extensively used as a PKC inhibitor and its antiparasitic effects described. In this research, we analyze the antikinetoplastid activities of three indolocarbazole (ICZs) alkaloids of the family of staurosporine STS, 2-4, and the commercial ICZs rebeccamycin (5), K252a (6), K252b (7), K252c (8), and arcyriaflavin A (9) in order to establish a plausive approach to the mode of action and to provide a preliminary qualitative structure-activity analysis. The most active compound was 7-oxostaurosporine (7OSTS, 2) that showed IC50 values of 3.58 ± 1.10; 0.56 ± 0.06 and 1.58 ± 0.52 µM against L. amazonensis; L. donovani and T. cruzi, and a Selectivity Index (CC50/IC50) of 52 against amastigotes of L. amazonensis compared to the J774A.1 cell line of mouse macrophages.


Assuntos
Antiprotozoários/farmacologia , Carbazóis/farmacologia , Kinetoplastida/efeitos dos fármacos , Streptomyces/química , Animais , Antiprotozoários/química , Bioensaio , Carbazóis/química , Carbazóis/toxicidade , Morte Celular/efeitos dos fármacos , Linhagem Celular , Concentração Inibidora 50 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Metaboloma , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Moleculares , Parasitos/efeitos dos fármacos , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia , Testes de Toxicidade
9.
Molecules ; 24(23)2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31771116

RESUMO

Gaiadandendron punctatum G.Don. (violeta de campo) is a plant used in traditional medicine by the Saraguro people, an ancient indigenous group that lives in southern Ecuador. From samples collected in the region, six glycoside flavonoids, five with quercetin and one with kaempferol as aglycon, were isolated and characterized from hydroalcoholic extracts of leaves and flowers. Rutin (2) was found in flowers and leaves, nicotiflorin (1) was found in flowers, artabotryside A (3) was found in leaves, and three novel quercetin flavonoid glycosides were isolated, elucidated, and characterized via 1D and 2D NMR experiments (1H, 13C, COSY, DEPT, HMBC, HSQC, TOCSY, NOESY, ROESY), acid hydrolysis-derivatization-GC-MS analysis, HPLC-MS, IR, UV, and optical rotation. The new quercetin flavonoid glycosides were named hecpatrin (4) (isolated from leaves), gaiadendrin (5) (isolated from leaves), and puchikrin (6) (isolated from flowers). The hydroalcoholic extracts of the leaves presented antimicrobial activity against Micrococcus luteus, Staphylococcus aureus, and Enterococcus faecalis and the hydroalcoholic extract of the flowers was active against Micrococcus luteus. However, glycoside flavonoids presented scarce antimicrobial activity against bacteria. Hydroalcoholic extracts from leaves and flowers and their secondary metabolites showed inhibition against the α-glucosidase enzyme at different concentrations. Rutin, gaiadendrin, and nicotiflorin showed competitive α-glucosidase inhibition, while hecpatrin presented non-competitive inhibition.


Assuntos
Anti-Infecciosos/isolamento & purificação , Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Loranthaceae/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Equador , Enterococcus faecalis/efeitos dos fármacos , Flavonoides/química , Flavonoides/farmacologia , Flores/química , Cromatografia Gasosa-Espectrometria de Massas , Glicosídeos/química , Glicosídeos/farmacologia , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Quercetina , Staphylococcus aureus/efeitos dos fármacos
10.
Mar Drugs ; 17(10)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627366

RESUMO

Indolocarbazoles are a family of natural alkaloids characterized by their potent protein kinase and topoisomerase I inhibitory activity. Among them, staurosporine (1) has exhibited promising inhibitory activity against parasites. Based on new insights on the activity and mechanism of action of STS in Acanthamoeba parasites, this work reports the isolation, identification, and the anti-Acanthamoeba activity of the minor metabolites 7-oxostaurosporine (2), 4'-demethylamino-4'-oxostaurosporine (3), and streptocarbazole B (4), isolated from cultures of the mangrove strain Streptomyces sanyensis. A clear correlation between the antiparasitic activities and the structural elements and conformations of the indolocarbazoles 1-4 was observed. Also, the study reveals that 7-oxostaurosporine (2) affects membrane permeability and causes mitochondrial damages on trophozoites of A. castellanii Neff.


Assuntos
Acanthamoeba/efeitos dos fármacos , Antiparasitários/farmacologia , Streptomyces/metabolismo , Alcaloides/farmacologia , Carbazóis/farmacologia , Indóis/farmacologia , Mitocôndrias/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia
11.
Sci Rep ; 9(1): 11651, 2019 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-31406269

RESUMO

Recently, the search for novel therapeutic agents against Acanthamoeba species has been focused on the evaluation of natural resources. Among them, marine microorganisms have risen as a source of bioactive compounds with the advantage of the ability to obtain unlimited and constant amounts of the compounds in contrast to other natural sources such as plants. Furthermore, marine actinomycetes have recently been reported as highly rich in bioactive agents including salinosporamides, xiamycines, indolocarbazoles, naphtyridines, phenols, dilactones such as antimycines and macrolides among others. In this study, staurosporine (STS) was isolated from a strain of Streptomyces sanyensis and tested against Acanthamoeba to characterize the therapeutic potential of STS against this protozoan parasite. We have established that STS is active against both stages of the Acanthamoeba life cycle, by the activation of Programmed Cell Death via the mitochondrial pathway of the trophozoite. We have also established that STS has relatively low toxicity towards a macrophage cell line. However, previous studies have highlighted higher toxicity levels induced on other vertebrate cell lines and future research to lower these toxicity issues should be developed.


Assuntos
Acanthamoeba castellanii/efeitos dos fármacos , Amebicidas/farmacologia , Organismos Aquáticos/química , Estaurosporina/farmacologia , Streptomyces/química , Acanthamoeba castellanii/citologia , Amebíase/tratamento farmacológico , Amebíase/parasitologia , Amebicidas/isolamento & purificação , Amebicidas/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Humanos , Macrófagos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Estaurosporina/isolamento & purificação , Estaurosporina/uso terapêutico , Testes de Toxicidade Aguda , Trofozoítos/citologia , Trofozoítos/efeitos dos fármacos
12.
J Ethnopharmacol ; 225: 319-326, 2018 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-30030122

RESUMO

ETHNOBOTANICAL AND ETHNOMEDICINAL RELEVANCE: The importance given in Ecuador to the rescue of traditional knowledge and nutritional value of ancestral foods and drinks, has stimulated our investigation of the chemical composition and some biological activities of M. fragrans ('arrayán') essential oil, a natural aromatic additive used in the preparation of the traditional fruit-juice 'colada morada', which is typically drunk in the Day of the Dead or All Soul´s Day. MATERIAL AND METHODS: Different essential oils of Myrcianthes fragrans (Sw.) McVaught were obtained by hydrodistillation of the aerial parts of the plant collected in Cerro Villonaco (Loja-Ecuador) at three different phenological growth stages, i.e., during foliation (Fo), flowering (Fl) and fruiting (Fr) stages. The chemical compositions of the essential oils were determined by GC/MS and GC/FID techniques. The antimicrobial activities were determined by the broth microdilution method and reported as minimal inhibitory concentration (MIC, ug/mL). AIMS OF THE STUDY: i) to investigate the traditional uses of arrayán (M. fragrans) in the South region of Ecuador; ii) to identify the main components of the essential oils isolated at different phenological stages; iiì) to test the antimicrobial activity of the essential oils against bacteria and yeasts causing human ailments and a yeast causing food spoilage. RESULTS: 37, 46 and 38 compounds, representing 96.5%, 96.2%, and 95.6% of the three essential oils (Fo, Fl and Fr), respectively, have been identified. Oxygenated monoterpenes (OM) were the major components with percentages of 63.1 (Fo), 49.4 (Fl), and 61.9% (Fr), respectively. The main constituents of the essential oils were the monoterpene aldehydes geranial (1) and neral (2), the content of which varied, depending on the phenological development stage of the plant, spanning from 31.1% and 23.6% (Fo), to 23.6% and 17.8% (Fl), and 29.7% and 24.3% (Fr), respectively. In vitro antimicrobial tests showed that the essential oils from M. fragrans exhibited good activity against the Gram-negative bacteria, K. pneumoniae, and against the yeasts, C. albicans and S. cerevisiae. CONCLUSIONS: The oil is characterized by a high concentration of the monoterpene aldehydes geranial and neral (citral), that make the aroma of colada morada prepared in southern Ecuador quite different from the beverage made in other regions of the country, where other types of myrtles (Myrtaceae spp.) are used. Moreover, the oil may become a new rich source of the important industrial chemical citral. The pleasant aromatic properties and the good in vitro antimicrobial activity of arrayán oil suggest a plausible scientific explanation for the traditional uses of the plant not only as a natural aromatizer of a traditional beverage but also as a natural anti-infective and anti-yeast agent.


Assuntos
Anti-Infecciosos , Myrtaceae , Óleos Voláteis , Anti-Infecciosos/análise , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Bebidas , Equador , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia
13.
Molecules ; 23(1)2018 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-29324657

RESUMO

The phytochemical investigation of both volatile and fixed metabolites of Clinopodium taxifolium (Kunth) Govaerts (Lamiaceae) was performed for the first time. It allowed the isolation and characterization of the essential oil and six known compounds: carvacrol (1), squalane (2), uvaol (3), erythrodiol (4), ursolic acid (5), and salvigenin (6). Their structures were identified and characterized by Nuclear Magnetic Resonance (NMR) and Gas Chromatography coupled to Mass Spectroscopy (GC-MS), and corroborated by literature. The essential oil of the leaves was obtained by hydrodistillation in two different periods and analyzed by GC-MS and GC coupled to Flame Ionization Detector (GC-FID). A total of 54 compounds were detected, of which 42 were identified (including trace constituents). The major constituents were carvacrol methyl ether (18.9-23.2%), carvacrol (13.8-16.3%) and, carvacryl acetate (11.4-4.8%). The antibacterial activities were determined as Minimum Inhibition Concentration (MIC) against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa and Micrococcus luteus. The hexane and methanol extracts exhibited activity only against Klebsiella pneumoniae (250 and 500 µg/mL respectively), while the ethyl acetate extract was inactive. The hypoglycemic activity was evaluated by the in vitro inhibition of α-glucosidase. The ethyl acetate (EtOAc) extract showed strong inhibitory activity with IC50 = 24.88 µg/mL, however methanolic and hexanic extracts showed weak activity. As a pure compound, only ursolic acid showed a strong inhibitory activity, with IC50 = 72.71 µM.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Lamiaceae/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , alfa-Glucosidases/química , Bactérias/efeitos dos fármacos , Lamiaceae/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Metabolismo Secundário
14.
Pharmaceuticals (Basel) ; 10(4)2017 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-29088082

RESUMO

This study investigated the chemical composition, physical proprieties, biological activity, and enantiomeric analysis of the essential oil from the aerial parts of Niphogeton dissecta (culantrillo del cerro) from Ecuador, obtained by steam distillation. The qualitative and quantitative analysis of the essential oil was realized by gas chromatographic and spectroscopic techniques (GC-MS and GC-FID). Acorenone B was identified by GC-MS and NMR experiments. The enantiomeric distribution of some constituents has been assessed by enantio-GC through the use of a chiral cyclodextrin-based capillary column. We identified 41 components that accounted for 96.46% of the total analyzed, the major components were acorenone B (41.01%) and (E)-ß-ocimene (29.64%). The enantiomeric ratio of (+)/(-)-ß-pinene was 86.9:13.1, while the one of (+)/(-)-sabinene was 80.9:19.1. The essential oil showed a weak inhibitory activity, expressed as Minimal Inhibitory Concentration (MIC), against Enterococcus faecalis (MIC 10 mg/mL) and Staphylococcus aureus (MIC 5 mg/mL). Furthermore, it inhibited butyrylcholinesterase with an IC50 value of 11.5 µg/mL. Pure acorenone B showed inhibitory activity against both acetylcholinesterase and butyrylcholinesterase, with IC50 values of 40.8 µg/mL and 10.9 µg/mL, respectively.

15.
Nat Prod Commun ; 12(4): 533-535, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30520590

RESUMO

Two phenols, bakuchiol (1) and 3-hydroxybakuchiol (2), and two isoflavone glycosides, daidzin (3) and genistin (4) were isolated from Otholobium mexicanum J. W. Grimes (Fabaceae). Moreover, the ability of the raw extract and isolated metabolites to inhibit the enzymes α-amylase and α-glucosidase was evaluated in vitro. In the α-amylase assay, the methanolic extract exhibited a moderate inhibitory activity with an IC50 of 470 µg/mL, while inhibition percentages of bakuchiol (1), 3-hydroxybakuchiol (2), and daidzin (3) were less than 25% at the maximum dose tested (1 µM). Genistin (4) exhibited a poor activity with an IC50 of 805 µM. In the α-glucosidase assay, the methanolic extract exhibited a strong inhibitory activity with an IC50 value of 32 µg/mL, while 3-hydroxybakuchiol (2) exhibited a moderate inhibitory activity with an IC50 of 345 µM. Daidzin (3) and genistin (4) exhibited lower inhibitory activity with IC50 values of 564 µM and 913 µM, respectively. Bakuchiol (1) exhibited a poor inhibitory activity with an inhibition percentage less than 10% at the maximum dose tested (1 mM).


Assuntos
Inibidores Enzimáticos/química , Fabaceae/química , Hipoglicemiantes/química , Isoflavonas/química , Extratos Vegetais/química , Animais , Inibidores Enzimáticos/isolamento & purificação , Hipoglicemiantes/isolamento & purificação , Isoflavonas/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Suínos , alfa-Amilases/química , alfa-Glucosidases/química
16.
Molecules ; 21(11)2016 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-27827864

RESUMO

The phytochemical investigation of Muehlenbeckia tamnifolia, collected in Loja-Ecuador, led to the isolation of nine known compounds identified as: lupeol acetate (1); cis-p-coumaric acid (2); lupeol (3); ß-sitosterol (4) trans-p-coumaric acid (5); linoleic acid (6) (+)-catechin (7); afzelin (8) and quercitrin (9). The structures of the isolated compounds were determined based on analysis of NMR and MS data, as well as comparison with the literature. The hypoglycemic activity of crude extracts and isolated compounds was assessed by the ability to inhibit α-amylase and α-glucosidase enzymes. The hexane extract showed weak inhibitory activity on α-amylase, with an IC50 value of 625 µg·mL-1, while the other extracts and isolated compounds were inactive at the maximum dose tested. The results on α-glucosidase showed more favorable effects; the hexanic and methanolic extracts exhibited a strong inhibitory activity with IC50 values of 48.22 µg·mL-1 and 19.22 µg·mL-1, respectively. Four of the nine isolated compounds exhibited strong inhibitory activity with IC50 values below 8 µM, much higher than acarbose (377 uM). Linoleic acid was the most potent compound (IC50 = 0.42 µM) followed by afzelin, (+)-catechin and quercitrin.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polygonaceae/química , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases , Ativação Enzimática/efeitos dos fármacos , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Concentração Inibidora 50 , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia
17.
Pharm Biol ; 53(12): 1826-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25880141

RESUMO

CONTEXT: Marine natural products are a rich source of potent, selective, and structurally novel compounds. Marine bacteria are considered the most promising source of biologically active compounds which can be applied to treat a wide range of diseases. OBJECTIVE: The current study was designed to establish the bases for a future marine exploration in the Ecuadorian coast based on the molecular identification of a marine bacterium and its potential use as an antibacterial or cytotoxic compounds source. MATERIALS AND METHODS: Isolation and characterization of the marine bacterium were carried out through microbiological methods from desiccated sediment. Molecular identification was made by means of 16S rDNA analysis. MIC was measured by the microdilution broth method against six pathogenic bacteria: two Gram positive and four Gram negative strains. Cytotoxicity was evaluated by Crystal violet assay against breast adenocarcinoma (MCF7) and ductal carcinoma (T47D and ZR-75-30). RESULTS: Our present study has shown that EtOAc extract and fraction A1 obtained from marine Streptomyces sp. revealed the maximal antibacterial and cytotoxic activity. Enterococcus faecalis was found to be more sensitive strain (MIC 0.78 µg/ml) than the other five bacteria tested. ZR-75-30 and T47D cell lines were found to be more sensitive (IC50 value, 31.88 ± 0.05 and 68.35 ± 0.12 µg/ml) than adenocarcinoma MCF7 (IC50 value was 83.65 ± 0.06 µg/ml). DISCUSSION AND CONCLUSION: The results obtained herein indicate that EtOAc extract of Streptomyces sp. has shown a strong antibacterial activity as well as moderate cytotoxic activity which make it a good candidate for metabolite isolation.


Assuntos
Antibacterianos/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Citotoxinas/isolamento & purificação , Sedimentos Geológicos/análise , Streptomyces , Antibacterianos/farmacologia , Produtos Biológicos/farmacologia , Citotoxinas/farmacologia , Sedimentos Geológicos/microbiologia , Humanos , Testes de Sensibilidade Microbiana/métodos , Filogenia
18.
J Nanosci Nanotechnol ; 13(3): 1717-26, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23755579

RESUMO

Amoxicillin (AMOX) was successfully encapsulated at different concentrations into poly(epsilon-caprolactone) (PCL) by the electrospinning technique, and mats of non-woven fibers were obtained and characterized in terms of morphology, in vitro release and antibacterial properties. The scanning electron microscopy evidenced the nanofibrous structure of the pristine PCL, composed of individual, uniform, and randomly oriented fibres with an average diameter ranging around 0.8 micron. The addition of amoxicillin at different concentrations (3, 5 and 7 wt%) did not evidence change in the fiber morphology. The release curves, for all samples, present mainly two stages: a first stage, quick as a "burst," is followed by a second slow stage. The burst was analyzed as a function of amoxicillin concentration and thickness of the membranes, and values corresponding to absence of burst were individuated. In the second stage the release was found very slow extending up to months for the most concentrated sample. The antibacterial activity of the electrospun fibers was effective to inhibit in different proportions Staphylococcus aureus, Enterococcus faecalis and Escherichia coli. The properties of the filled membranes and their capability for local delivery of antibiotics make them suitable for biomedical applications.


Assuntos
Amoxicilina/administração & dosagem , Antibacterianos/administração & dosagem , Poliésteres/química , Amoxicilina/química , Amoxicilina/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Preparações de Ação Retardada , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Staphylococcus aureus/efeitos dos fármacos , Resistência à Tração , Difração de Raios X
19.
Rev. bras. farmacogn ; 23(2): 370-373, Mar.-Apr. 2013. ilus, tab
Artigo em Inglês | LILACS-Express | LILACS | ID: lil-669511

RESUMO

The MeOH extract of Piper ecuadorense Sodiro, Piperaceae, was chosen for metabolite isolation and elucidation due to the strong antifungal activity exhibited, measured by means of the broth microdilution method. Two known flavonoids: pinostrobin (1) and pinocembrin (2) were isolated from 4.16 g. of dichloromethane extract by column chromatography, using a gradient of hexane/EtOAc. A total of 20 mg of 1 were obtained from the fraction eluted with hexane-EtOAc 95:5 v/v, and 100 mg of 2 were obtained from the fraction eluted with hexane-EtOAc 85:15 v/v. The MIC values of the MeOH extract was 31.25 µg/mL for Trichophyton mentagrophytes ATCC® 28185 and 62.5 µg/mL for Trichophyton rubrum ATCC® 28188. The MIC value of pinocembrin was 125 µg/mL for Trichophyton mentagrophytes ATCC® 28185 and Trichophyton rubrum ATCC® 28188. Pinostrobin in antifungal test was not active against fungi tested.

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