Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-38035540

RESUMO

Carotenoids, such as lycopene and ß-carotene, have been widely recognized for their antioxidant properties and potential health benefits. Accurate quantification of carotenoids in plant extracts is essential for nutritional assessment, quality control, and research investigations. This study introduces an innovative method for quantifying lycopene and ß-carotene, in plant extracts and aims to bridge the gap between complex and expensive carotenoid quantification techniques and the need for accessible methods that can be widely adopted. The primary difference between HPLC and HPTLC lies in the medium used for separation. HPLC employs a liquid phase within columns, while HPTLC utilizes a thin layer of adsorbent on a plate. This distinction impacts factors like equipment, cost, and analysis time. The VisionCats software, combined with the CAMAG Visualizer-2, allows the semi-quantification of metabolites using an image-based evaluation method enabling the simultaneous assessment of qualitative and semi-quantitative information from the HPTLC images. Sample preparation involves washing and drying the vegetal material, followed by dichloromethane extraction. HPTLC analysis is performed using the CAMAG Advanced Herbal System, and the validation studies include establishing calibration curves and determining the detection threshold and minimum quantification threshold for lycopene and ß-carotene. Specificity and precision were evaluated to ensure accurate identification and repeatability of the method. Data analysis involves selecting the regression method based on the nature of the data and assessing the goodness of fit using the R2 value. The results showed distinct peaks corresponding to lycopene and ß-carotene in the chromatograms of the plant extract samples. The visualizer-based method demonstrates good specificity and precision, with no interfering peaks observed and low relative standard deviation. The method shows promising results regarding specificity, precision, and reliability. It has the potential for broader implementation in carotenoid research and rapid monitoring of carotenoid content in various agricultural and food products, particularly in resource-limited settings. Further optimization and validation on a wider range of samples would enhance the applicability of this method in carotenoid research. Sample preparation involves washing and drying the vegetal material, followed by dichloromethane extraction. HPTLC analysis is performed using the CAMAG Advanced Herbal System, and the validation studies include establishing calibration curves and determining the detection threshold and minimum quantification threshold for lycopene and ß-carotene. Specificity and precision were evaluated to ensure accurate identification and repeatability of the method. Data analysis involves selecting the regression method based on the nature of the data and assessing the goodness of fit using the R2 value. The results showed distinct peaks corresponding to lycopene and ß-carotene in the chromatograms of the plant extract samples. The visualizer-based method demonstrates good specificity and precision, with no interfering peaks observed and low relative standard deviation. The method shows promising results regarding specificity, precision, and reliability. It has the potential for broader implementation in carotenoid research and for rapid screening and monitoring of carotenoid content in various agricultural and food products, particularly in resource-limited settings. Further optimization and validation on a wider range of samples would enhance the applicability of this method in carotenoid research.


Assuntos
Solanum lycopersicum , beta Caroteno , Licopeno , beta Caroteno/análise , Reprodutibilidade dos Testes , Cloreto de Metileno/análise , Carotenoides , Extratos Vegetais
2.
J Ethnopharmacol ; 301: 115840, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36257342

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Approximately 80% of people in developing countries depend on medicinal plants for their health care. Tridax procumbens (T. procumbens) and Allium sativum (A. sativum) have beneficial effects against parasitic and bacterial diseases. On the other side, the biological activity of the oxylipin (3S)-16,17-didehydrofalcarinol isolated from T. procumbens against the parasite Leishmania mexicana has been verified. AIM OF THE STUDY: To evaluate the acute oral toxicity of the methanolic extract of T. procumbens, the aqueous extract of A. sativum, their mixture, and pure oxylipin (3S)-16,17-didehydrofalcarinol in BALB/c mice. MATERIALS AND METHODS: Doses of 2000 and 5000 mg/kg of the methanolic extract of T. procumbens, the aqueous extract of A. sativum, and their mixture (1:1), and doses of 300 and 500 mg/kg of pure oxylipin were administered orally to female mice of the strain BALB/c, which were observed for 72 h in search of signs of toxicity. After 14 days, the animals were euthanized, blood was extracted for the measurement of transaminases, and the livers were recovered and stained with hematoxylin/eosin for histopathological analysis. RESULTS: No clinical signs of toxicity were observed in any of the animals dosed with T. procumbens and A. sativum extracts, while the majority of the animals dosed with pure oxylipin showed signs of toxicity and died. There was no difference in the weight index in most of the animals, except for the animals treated with T. procumbens at doses of 2000 mg/kg who presented an increase in the weight index, nor was there a correlation between the dose of A. sativum and the mixture and food consumption; however, a direct proportional correlation was observed between T. procumbens dose and food consumption. In none of the animals dosed with T. procumbens, A. sativum, and the mixture there was a difference in the levels of transaminases. In the histopathology study, slight lesions were observed in the hepatocytes of the mice treated with T. procumbens, A. sativum, and their mixture at doses of 2000 and 5000 mg/kg. On the other side, moderate injuries were observed in animals treated with pure oxylipin and it was considered as toxic due to almost all the animals died. CONCLUSION: The extracts of T. procumbens and A. sativum evaluated and applied orally did not cause signs of acute toxicity or severe liver damage, suggesting to evaluate their chronic toxicity including other biochemical parameters in the future. However, pure oxylipin caused signs of acute toxicity and death so it is recommended to work with lower doses.


Assuntos
Asteraceae , Alho , Camundongos , Animais , Camundongos Endogâmicos BALB C , Oxilipinas , Extratos Vegetais/toxicidade , Antioxidantes , Transaminases
3.
Pathogens ; 9(10)2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33050398

RESUMO

Fusarium equiseti strain FCHE and Fusarium oxysporum strain FCHJ were isolated from the roots of wilting habanero pepper (Capsicum chinense Jacq.) seedlings with root rot. Toward developing a biorational control of these serious phytopathogenic strains, ethanolic (EE) and aqueous (AE) extracts of different vegetative parts of 40 tropical native plants of the Yucatán Peninsula were screened for antifungal activity. Extracts of six out of 40 assayed plants were effective, and the most inhibitory extracts were studied further. EEs from Mosannona depressa (bark from stems and roots), Parathesis cubana (roots), and Piper neesianum (leaves) inhibited mycelial growth of both strains. Each active EE was then partitioned between hexane and acetonitrile. The acetonitrile fraction from M. depressa stem bark (MDT-b) had the lowest minimum inhibitory concentration of 1000 µg/mL against both pathogens and moderate inhibitory concentration (IC50) of 462 against F. equiseti and 472 µg/mL against F. oxysporum. After 96 h treatment with EE from M. depressa stem bark, both strains had distorted hyphae and conidia and collapsed conidia in scanning electron micrographs. Liquid chromatography-ultraviolet-high resolution mass spectrometry analysis revealed that the major component of the fraction was α-asarone. Its antifungal effect was verified using a commercial standard, which had an IC50 of 236 µg/mL against F. equiseti and >500 µg/mL against F. oxysporum. Furthermore, the P. cubana hexane fraction and P. neesianum acetonitrile fraction had antifungal activity against both Fusarium pathogens. These compounds provide new options for biorational products to control phytopathogenic fungi.

4.
Phytochem Anal ; 31(2): 183-190, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31343078

RESUMO

INTRODUCTION: (3S)-16,17-Didehydrofalcarinol (1) has been isolated from Tridax procumbens and has proved to have notorious bioactivity against Leishmania mexicana. In this study, hexane fractions obtained from the methanol extract of each plant part (roots, stems, leaves, flowers, and fruits) of T. procumbens collected monthly during a year were analysed in order to determine the quantity of 1 associated with biotic variables. OBJECTIVE: The aim of this study was to find the season of the year in which the bioactive metabolite 1 is at the highest concentration and to correlate it with temperature, length of day light, and rainfall. METHODS: Hexane fractions were obtained by liquid-liquid extraction and an accurate quantitation of 1 was performed using gas chromatography with a flame ionisation detector (GC-FID) employing pelargonic acid vanillyl amide (2) as internal standard. Partial validation was based on linearity and precision. RESULTS: Our results indicated that the total content of 1 has significant variation (P ≤ 0.05) during the different collecting months. The total content of the metabolite reached its highest level in the roots of the plant during June in the rainfall season (0.0358 ± 0.001 mg/g), and its lowest values in February and March during the drought season (0.0015 ± 0.000 and 0.0008 ± 0.000 mg/g, respectively). CONCLUSION: Our study provided evidence that the content of 1 in roots is strongly influenced by the variables of the harvesting season, also indicating that the biosynthesis of the active metabolite is enhanced during the warm and rainy months.


Assuntos
Extratos Vegetais , Polímero Poliacetilênico , Di-Inos , Álcoois Graxos , Estações do Ano , Distribuição Tecidual
5.
Rev Soc Bras Med Trop ; 52: e20180505, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31271620

RESUMO

INTRODUCTION: The microscopic examination of microhematocrit tubes (mHCT) has been proposed as the gold standard for acute and congenital Chagas disease diagnosis. We compared different mHCT methodologies detecting T. cruzi parasites in the blood. METHODS: The rotating method, water mount, and immersion oil methods were compared for their suitability, sensitivity, and specificity. RESULTS: The rotating method was easier, faster, and more sensitive than the others with 100% specificity. CONCLUSIONS: The rotating method is feasible for laboratory technicians with standard training in microscopic techniques and is recommended for the diagnosis of acute Chagas disease in primary health care facilities.


Assuntos
Tubo Capilar , Centrifugação/métodos , Doença de Chagas/diagnóstico , Hematócrito/métodos , Parasitemia/diagnóstico , Trypanosoma cruzi/isolamento & purificação , Animais , Doença de Chagas/sangue , Doença de Chagas/parasitologia , Serviços de Laboratório Clínico , Humanos , Parasitemia/parasitologia , Sensibilidade e Especificidade
6.
Rev. Soc. Bras. Med. Trop ; 52: e20180505, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1041570

RESUMO

Abstract INTRODUCTION: The microscopic examination of microhematocrit tubes (mHCT) has been proposed as the gold standard for acute and congenital Chagas disease diagnosis. We compared different mHCT methodologies detecting T. cruzi parasites in the blood. METHODS: The rotating method, water mount, and immersion oil methods were compared for their suitability, sensitivity, and specificity. RESULTS: The rotating method was easier, faster, and more sensitive than the others with 100% specificity. CONCLUSIONS: The rotating method is feasible for laboratory technicians with standard training in microscopic techniques and is recommended for the diagnosis of acute Chagas disease in primary health care facilities.


Assuntos
Humanos , Animais , Trypanosoma cruzi/isolamento & purificação , Centrifugação/métodos , Doença de Chagas/diagnóstico , Parasitemia/diagnóstico , Tubo Capilar , Hematócrito/métodos , Sensibilidade e Especificidade , Doença de Chagas/parasitologia , Doença de Chagas/sangue , Parasitemia/parasitologia , Serviços de Laboratório Clínico
7.
Parasite ; 21: 15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24717526

RESUMO

We tested a mixture of Tridax procumbens, known for its direct action against Leishmania mexicana, and Allium sativum, known for its immunomodulatory effect, as an alternative to treat cutaneous leishmaniasis. Acute oral toxicity was tested with the Up-and-Down Procedure (UDP) using a group of healthy mice administered with either T. procumbens or A. sativum extracts and compared with a control group. Liver injury and other parameters of toxicity were determined in mice at day 14. The in vivo assay was performed with mice infected with L. mexicana promastigotes and treated with either a mixture of T. procumbens and A. sativum or each extract separately. The thickness of the mice's footpads was measured weekly. After the 12-week period of infection, blood samples were obtained by cardiac puncture to determine the total IgG, IgG1 and IgG2a immunoglobulins by a noncommercial indirect ELISA. We showed that the mixture of T. procumbens and A. sativum extracts was better at controlling L. mexicana infection while not being toxic when tested in the acute oral toxicity assay in mice. An increase in the ratio of IgG2a/IgG1 indicated a tendency to raise a Th1-type immune response in mice treated with the mixture. The mixture of T. procumbens and A. sativum extracts is a promising natural treatment for cutaneous leishmaniasis and its healing effects make it a good candidate for a possible new phytomedicine.


Assuntos
Antiprotozoários/uso terapêutico , Asteraceae , Alho , Fatores Imunológicos/uso terapêutico , Leishmania mexicana/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Administração Oral , Animais , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/imunologia , Antiprotozoários/administração & dosagem , Antiprotozoários/isolamento & purificação , Antiprotozoários/toxicidade , Peso Corporal/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Avaliação Pré-Clínica de Medicamentos , Feminino , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/toxicidade , Leishmania mexicana/imunologia , Leishmaniose Cutânea/parasitologia , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Tamanho do Órgão/efeitos dos fármacos , Fitoterapia/efeitos adversos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/toxicidade , Baço/efeitos dos fármacos , Baço/patologia
8.
J Ethnopharmacol ; 132(1): 303-8, 2010 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-20728517

RESUMO

AIM OF THE STUDY: Since one of the main health problems of the indigenous population are infectious bowel diseases, we decided to test Mayan medicinal potions used to treat these conditions against some of the causal agents. MATERIALS AND METHODS: Thirty-one herbal formulations used for the treatment of infectious bowel diseases were prepared according to the collected ethnobotanical data. Their activities were tested against some of the causal agents of diarrheic symptoms, such as Entamoeba histolytica, Giardia lamblia, Escherichia coli, Klebsiella pneumoniae, Salmonella typhi and Shigella flexneri. RESULTS: Nine formulations were active against bacteria (MIC=0.5 mg/ml), four on Entamoeba histolytica, and seven on Giardia lamblia (IC(50)≤20 µg/ml). CONCLUSIONS: This work supports the use of the traditional Mayan formulations against some infectious bowel diseases, and it is the first step towards their study.


Assuntos
Anti-Infecciosos/uso terapêutico , Disenteria/tratamento farmacológico , Medicina Tradicional , Preparações de Plantas/uso terapêutico , Plantas Medicinais/química , Anti-Infecciosos/isolamento & purificação , Disenteria/microbiologia , Disenteria/parasitologia , Etnobotânica , Humanos , Indígenas Norte-Americanos , México , Preparações de Plantas/isolamento & purificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA