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1.
Molecules ; 29(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38398567

RESUMO

Asteraceae (Compositae), commonly known as the sunflower family, is one of the largest plant families in the world and includes several species with pharmacological properties. In the search for new antiviral candidates, an in vitro screening against dengue virus (DENV) was performed on a series of dichloromethane and methanolic extracts prepared from six Asteraceae species, including Acmella bellidioides, Campuloclinium macrocephalum, Grindelia pulchella, Grindelia chiloensis, Helenium radiatum, and Viguiera tuberosa, along with pure phytochemicals isolated from Asteraceae: mikanolide (1), eupatoriopicrin (2), eupahakonenin B (3), minimolide (4), estafietin (5), 2-oxo-8-deoxyligustrin (6), santhemoidin C (7), euparin (8), jaceidin (9), nepetin (10), jaceosidin (11), eryodictiol (12), eupatorin (13), and 5-demethylsinensetin (14). Results showed that the dichloromethane extracts of C. macrocephalum and H. radiatum and the methanolic extracts prepared from C. macrocephalum and G. pulchella were highly active and selective against DENV-2, affording EC50 values of 0.11, 0.15, 1.80, and 3.85 µg/mL, respectively, and SIs of 171.0, 18.8, >17.36, and 64.9, respectively. From the pool of phytochemicals tested, compounds 6, 7, and 8 stand out as the most active (EC50 = 3.7, 3.1, and 6.8 µM, respectively; SI = 5.9, 6.7, and >73.4, respectively). These results demonstrate that Asteraceae species and their chemical constituents represent valuable sources of new antiviral molecules.


Assuntos
Asteraceae , Sesquiterpenos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Asteraceae/química , Cloreto de Metileno , Compostos Fitoquímicos/farmacologia , Antivirais/farmacologia , Sesquiterpenos/química
2.
Chem Biodivers ; 18(6): e2100064, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33950577

RESUMO

Baccharis dracunculifolia DC. and Baccharis microdonta DC. (Asteraceae) are woody species morphologically similar growing in Uruguay, where not taxonomists people often confuse them in field conditions. As the essential oil of B. dracunculifolia ('vassoura' oil) is highly prized by the flavor and fragrance industry, the correct differentiation of the two species is a key factor in exploiting them profitably and reasonably. To differentiate both Baccharis species, in this work their volatile expression profiles were studied as an alternative tool to determine authenticity and quality. Volatile organic compounds (VOCs) were monthly extracted during an entire year from aerial parts of wild populations by simultaneous distillation extraction (SDE), and studied by gas chromatography/mass spectrometry (GC/MS; identification) and conventional gas chromatography (GC-FID; component abundances determination). Enantioselective gas chromatography/mass spectrometry (Es-GC/MS) was applied in the search of parameters able to ensure genuineness of each species extract. Qualitative VOCs profiles were found to be similar for both species, being ß-pinene, limonene, spathulenol, caryophyllene oxide, and viridiflorol the main components. However, the abundance of those VOCs were two to ten times higher in B. dracunculifolia than in B. microdonta during the year of study. These Baccharis spp. showed species-specific patterns of VOCs expression according to the seasonality, and interestingly, oxygenated compounds (trans-pinocarveol and myrtenal) increased their abundances at full-flowering stages. The enantiomeric distribution of selected monoterpenes (α- and ß-pinenes, limonene, linalool, terpinen-4-ol, and α-terpineol) presented differential values for both Baccharis spp., meaning that Es-GC might be a useful tool for differentiating chemically both species in Uruguay for genuineness determination purposes.


Assuntos
Baccharis/química , Óleos Voláteis/isolamento & purificação , Estações do Ano , Compostos Orgânicos Voláteis/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/química , Compostos Orgânicos Voláteis/química
3.
Molecules ; 26(9)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066562

RESUMO

The Stevia genus (Asteraceae) comprises around 230 species, distributed from the southern United States to the South American Andean region. Stevia rebaudiana, a Paraguayan herb that produces an intensely sweet diterpene glycoside called stevioside, is the most relevant member of this genus. Apart from S. rebaudiana, many other species belonging to the Stevia genus are considered medicinal and have been popularly used to treat different ailments. The members from this genus produce sesquiterpene lactones, diterpenes, longipinanes, and flavonoids as the main types of phytochemicals. Many pharmacological activities have been described for Stevia extracts and isolated compounds, antioxidant, antiparasitic, antiviral, anti-inflammatory, and antiproliferative activities being the most frequently mentioned. This review aims to present an update of the Stevia genus covering ethnobotanical aspects and traditional uses, phytochemistry, and biological activities of the extracts and isolated compounds.


Assuntos
Antioxidantes/farmacologia , Diterpenos do Tipo Caurano/química , Glucosídeos/química , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química , Stevia/química , Edulcorantes/química , Animais , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Etnobotânica , Etnofarmacologia , Flavonoides/análise , Células HeLa , Humanos , Concentração Inibidora 50 , Medicina Tradicional , Camundongos , Extratos Vegetais/química , Ratos
4.
Molecules ; 25(9)2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32344932

RESUMO

The sesquiterpene lactones eupatoriopicrin, estafietin, eupahakonenin B and minimolide have been isolated from Argentinean Astearaceae species and have been found to be active against Trypanosoma cruzi epimastigotes. The aim of this work was to evaluate the activity of these compounds by analyzing their effect against the stages of the parasites that are infective for the human. Even more interesting, we aimed to determine the effect of the most active and selective compound on an in vivo model of T. cruzi infection. Eupatoriopicrin was the most active against amastigotes and tripomastigotes (IC50 = 2.3 µg/mL, and 7.2 µg/mL, respectively) and displayed a high selectivity index. This compound was selected to study on an in vivo model of T. cruzi infection. The administration of 1 mg/kg/day of eupatoriopicrin for five consecutive days to infected mice produced a significant reduction in the parasitaemia levels in comparison with non-treated animals (area under parasitaemia curves 4.48 vs. 30.47, respectively). Skeletal muscular tissues from eupatopicrin-treated mice displayed only focal and interstitial lymphocyte inflammatory infiltrates and small areas of necrotic; by contrast, skeletal tissues from T. cruzi infected mice treated with the vehicle showed severe lymphocyte inflammatory infiltrates with necrosis of the adjacent myocytes. The results indicate that eupatoriopicrin could be considered a promising candidate for the development of new therapeutic agents for Chagas disease.


Assuntos
Asteraceae/química , Lactonas/farmacologia , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Tripanossomicidas/farmacologia , Animais , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Doença de Chagas/patologia , Humanos , Lactonas/química , Camundongos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Sensibilidade e Especificidade , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Tripanossomicidas/química , Tripanossomicidas/isolamento & purificação , Trypanosoma cruzi/efeitos dos fármacos
5.
Molecules ; 24(7)2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30925657

RESUMO

Sesquiterpene lactones are naturally occurring compounds mainly found in the Asteraceae family. These types of plant metabolites display a wide range of biological activities, including antiprotozoal activity and are considered interesting structures for drug discovery. Four derivatives were synthesized from estafietin (1), isolated from Stevia alpina (Asteraceae): 11ßH,13-dihydroestafietin (2), epoxyestafietin (3a and 3b), 11ßH,13-methoxyestafietin, (4) and 11ßH,13-cianoestafietin. The antiprotozoal activity against Trypanosoma cruzi and Leishmania braziliensis of these compounds was evaluated. Epoxyestafietin was the most active compound against T. cruzi trypomastigotes and amastigotes (IC50 values of 18.7 and 2.0 µg/mL, respectively). Estafietin (1) and 11ßH,13-dihydroestafietin (2) were the most active and selective compounds on L. braziliensis promastigotes (IC50 values of 1.0 and 1.3 µg/mL, respectively). The antiparasitic activity demonstrated by estafietin and some of its derivatives make them promising candidates for the development of effective compounds for the treatment of Chagas disease and leihsmaniasis.


Assuntos
Leishmania braziliensis/efeitos dos fármacos , Sesquiterpenos de Guaiano/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Antiparasitários/química , Antiparasitários/farmacologia , Antiprotozoários/química , Antiprotozoários/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Morte Celular/efeitos dos fármacos , Chlorocebus aethiops , Espectroscopia de Prótons por Ressonância Magnética , Sesquiterpenos de Guaiano/química , Trypanosoma cruzi/crescimento & desenvolvimento , Células Vero
6.
Antonie Van Leeuwenhoek ; 108(5): 1047-57, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26342699

RESUMO

The main secondary metabolite of Senecio nutans is 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone (4HMBA). The antifungal activity of this compound and three derivatives was assessed using Candida albicans. 4HMBA exhibited the highest antifungal activity among the assayed compounds. The Fractional Inhibitory Concentration (FIC = 0.133) indicated a synergistic fungicidal effect of 4HMBA (5 mg L(-1)) and fluconazole (FLU) (0.5 mg L(-1)) against the C. albicans reference strain (ATCC 10231). Microscopy showed that 4HMBA inhibits filamentation and reduces cell wall thickness. Our findings suggest that 4HMBA is an interesting compound to diminish resistance to commercial fungistatic drugs such as fluconazole.


Assuntos
Acetofenonas/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Acetofenonas/química , Antifúngicos/química , Candida albicans/ultraestrutura , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Relação Dose-Resposta a Droga , Viabilidade Microbiana/efeitos dos fármacos
7.
Nat Prod Res ; 38(4): 690-695, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36938813

RESUMO

Chagas disease is an infection caused by the protozoan Trypanosoma cruzi, affecting 6-8 million people worldwide. Only two drugs are available for its treatment, having a limited efficacy and adverse side-effects. Estafietin is a sesquiterpene lactone isolated from Stevia alpina with in vitro activity against T. cruzi and low cytotoxicity against mammalian cells. The aim of this work was to predict the toxicologic profile of estafietin by in silico methods and assess its in vivo activity on a murine model of Chagas disease. Estafietin showed low toxicity according to pkCSM web tool and passed the PAINS filter from PAINS-remover web server. The treatment of infected mice with 1 mg/Kg/day of estafietin for five consecutive days administrated by intraperitoneal route significatively decreased parasitemia levels and reduced inflammatory infiltrates and myocyte damage on muscle tissue. These results suggest that estafietin had effect both on acute and chronic stages of the infection.


Assuntos
Doença de Chagas , Stevia , Tripanossomicidas , Trypanosoma cruzi , Humanos , Camundongos , Animais , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Doença de Chagas/tratamento farmacológico , Sesquiterpenos de Guaiano/farmacologia , Parasitemia/tratamento farmacológico , Lactonas/farmacologia , Lactonas/uso terapêutico , Mamíferos
8.
Nat Prod Res ; : 1-6, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579277

RESUMO

Fusarium graminearum causes destructive ear rot diseases in maize and wheat. New antifungals are essential to combat this pathogen, and aerial parts of Justicia species (Acanthaceae) are a potential source. We investigated the antifungal activity of extracts from stems and leaves of five Justicia species native to Northwest Argentina. The aerial parts were subjected to sequential extractions with dichloromethane, ethyl acetate, and methanol. The resulting extracts were tested by the disc diffusion method against F. graminearum strains. Only the leaf and stem extracts from J. xylosteoides displayed inhibitory effects, with the dichloromethane leaf extract as the most active. The compounds involved were identified as the lignans hinokinin, savinin, and isohibalactone. Both the dichloromethane extract and hinokinin synergised with tebuconazole, and inhibited deoxynivalenol biosynthesis. The identified compounds warrant further research as additives to azole fungicides for F. graminearum control.

9.
Pharmaceutics ; 16(3)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38543309

RESUMO

Chagas disease, caused by the protozoan Trypanosoma cruzi, affects 6-7 million people worldwide. The dichloromethane extract obtained from the aerial parts of Gymnocoronis spilanthoides var subcordata showed trypanocidal activity in vitro. The fractionation of the dewaxed organic extract via column chromatography led to the isolation of three diterpenoids: ent-9α,11α-dihydroxy-15-oxo-kaur-16-en-19-oic acid or adenostemmoic acid B, (16R)-ent-11α-hydroxy-15-oxokauran-19-oic acid and ent-11α-hydroxy-15-oxo-kaur-16-en-19-oic acid. These compounds showed IC50 values of 10.6, 15.9 and 4.8 µM against T. cruzi epimastigotes, respectively. When tested against amastigotes, the diterpenoids afforded IC50 values of 6.1, 19.5 and 60.6 µM, respectively. The cytotoxicity of the compounds was tested on mammalian cells using an MTT assay, resulting in CC50s of 321.8, 23.3 and 14.8 µM, respectively. The effect of adenostemmoic acid B on T. cruzi was examined at the ultrastructural level using transmission microscopy. Treatment with 20 µM for 48 h stimulated the formation of abnormal cytosolic membranous structures in the parasite. This compound also showed an anti-inflammatory effect in murine macrophages stimulated with LPS and other TLR agonists. Treatment of macrophages with adenostemmoic acid B was able to reduce TNF secretion and nitric oxide production, while increasing IL-10 production. The combination of adenostemmoic acid B with benznidazole resulted in greater inhibition of NF-kB and a decrease in nitrite concentration. The administration of adenostemmoic acid B to mice infected with trypomastigotes of T. cruzi at the dose of 1 mg/kg/day for five days produced a significant decrease in parasitemia levels and weight loss. Treatment with the association with benznidazole increased the survival time of the animals. In view of these results, adenostemmoic acid B could be considered a promising candidate for further studies in the search for new treatments for Chagas disease.

10.
Chem Biodivers ; 10(2): 251-61, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23418172

RESUMO

The aerial parts of lemon verbena (Aloysia citriodora PALÁU) are worldwide used due to their medicinal and aromatic properties. The essential-oil and acteoside contents have been proposed as the main quality markers for their pharmacological and organoleptic features. The northwestern region of Argentina has been repeatedly proposed as the place of origin for this species. For this reason, the essential-oil yields and chemical compositions of leaves of 25 populations of lemon verbena from both wild collections and experimental crops from this region were studied. Plants from six different collections were subsequently grown on the same experimental parcel located at Cerrillos, Salta province, during more than seven years. In addition, the acteoside contents determined in all the samples collected in 2010 showed significant variations (from 0.5 to 4.0%). Large differences were observed in the essential-oil composition and yields, which ranged from 0.4 to 2.1% (v/w). Nevertheless, most of the samples complied with the European Pharmacopoeia specifications. A remarkable chemical diversity with at least four clearly defined chemotypes was detected in this region. Therefore, it would be urgent to encourage actions to protect these genotypes of lemon verbena in the northwestern Argentina.


Assuntos
Glucosídeos/análise , Óleos Voláteis/análise , Fenóis/análise , Verbena/química , Argentina , Variação Genética , Genótipo , Verbena/genética
11.
Pharmaceutics ; 15(2)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36839969

RESUMO

Stevia species (Asteraceae) have been a rich source of terpenoid compounds, mainly sesquiterpene lactones, several of which show antiprotozoal activity. In the search for new trypanocidal compounds, S. satureiifolia var. satureiifolia and S. alpina were studied. Two sesquiterpene lactones, santhemoidin C and 2-oxo-8-deoxyligustrin, respectively, were isolated. These compounds were assessed in vitro against Trypanosoma cruzi stages, showing IC50 values of 11.80 and 4.98 on epimastigotes, 56.08 and 26.19 on trypomastigotes and 4.88 and 20.20 µM on amastigotes, respectively. Cytotoxicity was evaluated on Vero cells by the MTT assay. The effect of the compounds on trypanothyone reductase (TcTR), Trans-sialidase (TcTS) and the prolyl oligopeptidase of 80 kDa (Tc80) as potential molecular targets of T. cruzi was investigated. Santhemoidin C inhibited oligopeptidase activity when tested against recombinant Tc80 using a fluorometric assay, reaching an IC50 of 34.9 µM. Molecular docking was performed to study the interaction between santhemoidin C and the Tc80 protein, reaching high docking energy levels. Plasma membrane shedding and cytoplasmic vacuoles, resembling autophagosomes, were detected by transmission microscopy in parasites treated with santhemoidin C. Based on these results, santhemoidin C represents a promising candidate for further studies in the search for new molecules for the development of trypanocidal drugs.

12.
Fitoterapia ; 167: 105499, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37019368

RESUMO

Chagas disease, African trypanosomiasis and Leishmaniasis are neglected parasitic diseases which affect millions of people worldwide. In a previous work, we report the antiprotozoal activity of the dichloromethane extract of Mikania periplocifolia Hook. & Arn. (Asteraceae). The aim of this work was to isolate and identify the bioactive compounds present in the extract. The fractionation of the dichloromethane extract has led to the isolation of the sesquiterpene lactone miscandenin and the flavonoid onopordin, together with the sesquiterpene lactones mikanolide, dihydromikanolide and deoxymikanolide, which have previously shown antiprotozoal activity. Miscandenin and onopordin were assayed in vitro against Trypanosoma cruzi, T. brucei and Leishmania braziliensis. Miscandenin was active against T. cruzi trypomastigotes and amastigotes with IC50 values of 9.1 and 7.7 µg/ml, respectively. This sesquiterpene lactone and the flavonoid onopordin showed activity against T. brucei trypomastigotes (IC50 = 0.16 and 0.37 µg/ml) and L. braziliensis promastigotes (IC50 = 0.6 and 1.2 µg/ml), respectively. The CC50 values on mammalian cells were 37.9 and 53.4 µg/ml for miscandenin and onopordin, respectively. Besides, the pharmacokinetic and physicochemical properties of miscandenin were assessed in silico, showing a good drug-likeness profile. Our results highlight this compound as a promising candidate for further preclinical studies in the search of new drugs for the treatment of trypanosomiasis and leishmaniasis.


Assuntos
Antiprotozoários , Asteraceae , Leishmaniose , Mikania , Sesquiterpenos , Trypanosoma cruzi , Animais , Humanos , Asteraceae/química , Mikania/química , Cloreto de Metileno/uso terapêutico , Extratos Vegetais/química , Estrutura Molecular , Antiprotozoários/farmacologia , Leishmaniose/tratamento farmacológico , Flavonoides/farmacologia , Lactonas , Mamíferos
13.
ScientificWorldJournal ; 2012: 121253, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22919289

RESUMO

The aim of this study was to investigate the antiprotozoal and antiviral activities of four Argentinean Mikania species. The organic and aqueous extracts of Mikania micrantha, M. parodii, M. periplocifolia, and M. cordifolia were tested on Trypanosoma cruzi epimastigotes, Leishmania braziliensis promastigotes, and dengue virus type 2. The organic extract of M. micrantha was the most active against T. cruzi and L. braziliensis exhibiting a growth inhibition of 77.6 ± 4.5% and 84.9 ± 6.1%, respectively, at a concentration of 10 µg/ml. The bioguided fractionation of M. micrantha organic extract led to the identification of two active fractions. The chromatographic profile and infrared analysis of these fractions revealed the presence of sesquiterpene lactones. None of the tested extracts were active against dengue virus type 2.


Assuntos
Antiprotozoários/farmacologia , Antivirais/farmacologia , Mikania/química , Extratos Vegetais/farmacologia , Cromatografia Líquida de Alta Pressão , Vírus da Dengue/efeitos dos fármacos , Técnicas In Vitro , Leishmania braziliensis/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Trypanosoma cruzi/efeitos dos fármacos
14.
Artigo em Inglês | MEDLINE | ID: mdl-33628303

RESUMO

The dewaxed dichloromethane extract of Urolepis hecatantha and the compounds isolated from it were tested for their in vitro activity on Trypanosoma cruzi epimastigotes and Leishmania infantum promastigotes. The extract of U. hecatantha showed activity against both parasites with IC50 values of 7 µg/mL and 31 µg/mL, respectively. Fractionation of the dichloromethane extract led to the isolation of euparin, jaceidin, santhemoidin C, and eucannabinolide. The sesquiterpene lactones eucannabinolide and santhemoidin C were active on T. cruzi with IC50 values of 10 ± 2 µM (4.2 µg/mL) and 18 ± 3 µM (7.6 µg/mL), respectively. Euparin and santhemoidin C were the most active on L. infantum with IC50 values of 18 ± 4 µM (3.9 µg/mL) and 19 ± 4 µM (8.0 µg/mL), respectively. Eucannabinolide has also shown drug-like pharmacokinetic and toxicity properties.

15.
J Sci Food Agric ; 90(3): 385-90, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20355057

RESUMO

BACKGROUND: The present study describes the chemical analysis of the essential oil and oleoresins from caraway, which have been studied by using GC-MS. The paper also explains the importance of the extracted oil and oleoresins in the antioxidant activities of target plant species. RESULTS: GC-MS analysis of caraway essential oil showed 51 compounds representing about 96.6% of the total weight. The major components were dillapiole (44.6%), germacrene-beta (14.1%), nothoapiole (8.3%), and beta-selinene (6.8%), along with many other components in minor amounts. Major components in ethyl acetate and iso-octane oleoresins are dillapiole, nothoapiole and germacrene-beta, whereas in ethanol oleoresin contains dillapiole (25%), sitosterol (21.3%) stigmasterol (9.5%) and nothoapiole (8.1%). The antioxidant activity was evaluated by various antioxidant assays such as peroxide, thiobarbituric acid and p-anisidine values. These experiments were further supported by other complementary antioxidant assays such as ferric thiocyanate method in linoleic acid system, reducing power, and scavenging effects on 1,1'-diphenyl-2-picrylhydrazyl (DPPH). Both the caraway volatile oil and its oleoresins showed strong antioxidant activity in comparison with butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). CONCLUSION: This study provides additional information about the chemistry and antioxidant activity of caraway. Hence, caraway may be used as natural food preservatives.


Assuntos
Antioxidantes/farmacologia , Carum/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Antioxidantes/química , Frutas/química , Óleos Voláteis/química , Extratos Vegetais/química
16.
Int J Food Microbiol ; 305: 108242, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31176953

RESUMO

Fusarium meridionale and F. boothii cause Gibberella Ear Rot (GER) in maize. This study determined the effects of temperature (5-35 °C) and water activity (0.90-0.995 aw) on the growth, and deoxynivalenol (DON) and nivalenol (NIV) production of F. meridionale and F. boothii strains in maize grains. Fusarium graminearum sensu stricto strains from wheat were also tested. The three Fusarium species grew best at 0.995 aw and 25 °C. Growth was absent or marginal at 0.90 aw regardless of temperature. F. meridionale and F. boothii were sensitive to 30 °C and more affected by water stress than F. graminearum sensu stricto. The highest DON levels were at 0.995-0.97 aw and 30 °C and at 0.97 aw and 20 °C for F. graminearum sensu stricto, and at 0.995-0.97 aw and 20 °C for F. boothii. Fusarium meridionale reached maximum NIV accumulation at 0.995 aw and 20 °C. This produced DON at negligible levels compared to the other two Fusarium species. Growth of F. meridionale and F. boothii was well adapted to the usual autumn high humidity and mild temperatures associated with GER in northwest Argentina. Control strategies during grain development should be taken into account to reduce the risk of the presence of DON and NIV in the harvested grains.


Assuntos
Fusarium/metabolismo , Doenças das Plantas/microbiologia , Tricotecenos/metabolismo , Água/análise , Zea mays/microbiologia , Argentina , Fusarium/classificação , Fusarium/crescimento & desenvolvimento , Fusarium/isolamento & purificação , Umidade , Estações do Ano , Temperatura , Tricotecenos/análise , Triticum/química , Triticum/microbiologia , Água/metabolismo , Zea mays/química
17.
J Nat Prod ; 71(6): 967-71, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18500843

RESUMO

The agreement between theoretical and experimental vibrational circular dichroism curves of (4R,9R,10R)-(+)-african-1(5)-ene-2,6-dione (1) and (4R,9S,10R)-lippifoli-1(6)-en-5-one (2), isolated from the widely used plant Lippia integrifolia, allowed the determination of the conformation and absolute configuration of 1 and confirmed both structural features for 2. Molecular modeling of 1 and 2 was carried out by means of a systematic and a Monte Carlo search protocol followed by geometry optimization employing density functional theory calculations with the B3LYP/6-31G(d), B3LYP/DGDZVP, and/or B3PW91/DGDZVP2 functionals/basis sets. Validation of the minimum energy conformations for both tricyclic substances was achieved by comparison of the experimental and theoretical vicinal (1)H-(1)H NMR coupling constants obtained by DFT-GIAO calculations.


Assuntos
Dicroísmo Circular , Lippia/química , Plantas Medicinais/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Estereoisomerismo
18.
Food Chem Toxicol ; 46(10): 3295-302, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18706468

RESUMO

The essential oil and oleoresins (ethanol, methanol, CCl(4) and isooctane) of Zingiber officinale were extracted respectively by hydrodistillation and Soxhlet methods and subjected to GC-MS analysis. Geranial (25.9%) was the major component in essential oil; eugenol (49.8%) in ethanol oleoresin, while in the other three oleoresins, zingerone was the major component (33.6%, 33.3% and 30.5% for, methanol, CCl(4) and isooctane oleoresins, respectively). The antioxidant activity of essential oil and oleoresins were evaluated against mustard oil by peroxide, anisidine, thiobarbituric acid (TBA), ferric thiocyanate (FTC) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging methods. They were found to be better antioxidants than butylated hydroxyanisole (BHA). The antimicrobial properties were also studied using various food-borne pathogenic fungal and bacterial species. The essential oil and CCl(4) oleoresin showed 100% zone inhibition against Fusarium moniliforme. For other tested fungi and bacteriae, the essential oil and all oleoresins showed good to moderate inhibitory effects. Though, both essential oil and oleoresins were found to be effective, essential oil was found to be better than the oleoresins.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Zingiber officinale/química , Antibacterianos/química , Antifúngicos/química , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fungos/efeitos dos fármacos , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
19.
Food Chem Toxicol ; 45(9): 1650-61, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17408833

RESUMO

The antioxidant, antifungal and antibacterial potentials of volatile oils and oleoresin of Cinnamomum zeylanicum Blume (leaf and bark) were investigated in the present study. The oleoresins have shown excellent activity for the inhibition of primary and secondary oxidation products in mustard oil added at the concentration of 0.02% which were evaluated using peroxide, thiobarbituric acid, p-anisidine and carbonyl values. Moreover, it was further supported by other complementary antioxidant assays such as ferric thiocyanate method in linoleic acid system, reducing power, chelating and scavenging effects on 1,1'-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals. In antimicrobial investigations, using inverted petriplate and food poison techniques, the leaf and bark volatile oils has been found to be highly effective against all the tested fungi except Aspergillus ochraceus. However, leaf oleoresin has shown inhibition only for Penicillium citrinum whereas bark oleoresin has caused complete mycelial zone inhibition for Aspergillus flavus and A. ochraceus along with Aspergillus niger, Aspergillus terreus, P. citrinum and Penicillium viridicatum at 6 microL. Using agar well diffusion method, leaf volatile oil and oleoresin have shown better results in comparison with bark volatile oil, oleoresin and commercial bactericide, i.e., ampicillin. Gas chromatographic-mass spectroscopy studies on leaf volatile oil and oleoresin resulted in the identification of 19 and 25 components, which accounts for the 99.4% and 97.1%, respectively of the total amount and the major component was eugenol with 87.3% and 87.2%, respectively. The analysis of cinnamon bark volatile oil showed the presence of 13 components accounting for 100% of the total amount. (E)-cinnamaldehyde was found as the major component along with delta-cadinene (0.9%), whereas its bark oleoresin showed the presence of 17 components accounting for 92.3% of the total amount. The major components were (E)-cinnamaldehyde (49.9%), along with several other components.


Assuntos
Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Aspergillus/efeitos dos fármacos , Aspergillus/crescimento & desenvolvimento , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Relação Dose-Resposta a Droga , Eugenol , Cromatografia Gasosa-Espectrometria de Massas/métodos , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise , Óleos Voláteis/química , Penicillium/efeitos dos fármacos , Penicillium/crescimento & desenvolvimento , Extratos Vegetais/análise , Especificidade da Espécie , Fatores de Tempo
20.
Nat Prod Res ; 31(12): 1464-1467, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27879146

RESUMO

The composition of essential oils from leaves of Kazakhstan medicinal plants was analysed by GC-MS. The major compounds identified were 1,8-cineole (34.2%), myrcene (19.1%) and α-pinene (9.4%) in Ajania fruticulosa; 1,8-cineole (21.0%), ß-thujone (11.0%), camphor (8.5%), borneol (7.3%) and α-thujone (6.5%), in Achillea nobilis; camphor (47.3%), 1,8-cineole (23.9%), camphene (9.8%) and ß-thujone (6.0%) in Artemisia terrae-albae; 1,8-cineole(55.8%) and ß-pinene (6.2%) in Hyssopus ambiguus; α-thuyene(46.3%) and δ-cadinene(6.3%) in Juniperus sibirica; sabinene (64%) in Juniperus sabina; and α-pinene (51.5%), ß-phellandrene (11.2%) and δ-cadinene (6.3%) in Pinus sibirica. The essential oils did not show antifungal effect (MIC > 1.20 mg/mL) on Aspergillus carbonarius and Aspergillus niger, while the oils from A. nobilis, A. terrae-albae, H. ambiguus and J. sabina exhibited moderate and moderate to weak antimicrobial activities on Fusarium verticillioides (MIC = 0.60 mg/mL) and Fusarium graminearum (MIC = 0.60-1.20 mg/mL), respectively. A principal component analysis associated the antifungal activity (r2 > 0.80, p = 0.05) with the presence of borneol, camphor, camphene, 1,8-cineole,α- and ß-thujone, and of the oxygenated monoterpenes.


Assuntos
Antifúngicos/farmacologia , Óleos Voláteis/farmacologia , Plantas Medicinais/química , Cazaquistão , Folhas de Planta/química , Análise de Componente Principal
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