RESUMEN
AIM: To evaluate the antifungal activity of extracts of Chamaecostus cuspidatus against Candida and Trichophyton species. METHODS AND RESULTS: Crude ethanol extracts of leaves, stems and rhizomes were prepared and evaluated for antimicrobial activity. Only the rhizomes extract (RE) showed antifungal activity but had no inhibitory effect against bacteria (Staphylococcus aureus and Escherichia coli). The RE was then submitted to liquid-liquid partition with hexane (Hex), dichloromethane, chloroform, ethyl acetate and water. The Hex fraction (Hex Fr) from the RE was found to have the best antifungal effect. Three known saponins were isolated from the Hex Fr, of which two (dioscin and aferoside A) showed good antifungal activity. In addition, Hex Fr and the two bioactive compounds had no antibacterial effect, but exhibited fungicidal activity, caused significant changes in the morphology of the fungal cells and showed anti-Candida albicans biofilm activity. Finally, the bioactive plant products presented greater selectivity for fungal cells over normal human cells. CONCLUSIONS: The rhizomes of C. cuspidatus have bioactive saponins that function as effective antifungals against Candida and Trichophyton species, and have antibiofilm activity against C. albicans. SIGNIFICANCE AND IMPACT OF THE STUDY: Chamaecostus cuspidatus REs may have potential clinical application towards the management of superficial mycoses caused by Candida and Trichophyton species.
Asunto(s)
Antifúngicos/farmacología , Candida/efectos de los fármacos , Saponinas/farmacología , Trichophyton/efectos de los fármacos , Zingiberales/química , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/farmacología , Rizoma/química , Saponinas/química , Saponinas/aislamiento & purificaciónRESUMEN
Urban air contains many mutagenic pollutants. This research aimed to investigate the presence of mutagens in the air by short-term mutagenicity tests using bacteria, human cells and plants. Inflorescences of Tradescantia were exposed to air in situ for 6h, once a month from January to May, to monitor volatile compounds and micronuclei frequency was computed. On the same days PM10 was collected continuously for 24h. Half of each filter was extracted with organic solvents and studied by means of the Ames test, using Salmonella typhimurium TA98 and TA100 strains, and the comet assay on human leukocytes. A quarter of each filter was extracted with distilled water in which Tradescantia was exposed. PM10 concentration was particularly high in the winter season (> 50 µg/m(3)). In situ exposure of inflorescences to urban air induced a significant increase in micronuclei frequency at all the sites considered, but only in January (p < 0.01). Aqueous extracts collected in January and February induced genotoxic effects in Tradescantia exposed in the laboratory (p < 0.01). Ames test showed that organic extracts of winter urban air were able to induce genetic mutations in S. typhimurium TA98 strain (± S9), but not in TA100 strain, with a revertants/plate number nine times higher than the negative control. Comet assay showed that winter extracts were more toxic and genotoxic than spring extracts. All the mutagenicity tests performed confirmed that urban air in North Italy in winter contains both volatile and non-volatile genotoxic substances able to induce genetic damage in bacteria, human cells and plants.
Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Mutágenos/análisis , Contaminantes Atmosféricos/toxicidad , Ensayo Cometa , Humanos , Italia , Leucocitos/química , Leucocitos/efectos de los fármacos , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Mutágenos/toxicidad , Mutación Puntual/efectos de los fármacos , Polen/química , Polen/efectos de los fármacos , Salmonella typhimurium/química , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Tradescantia/química , Tradescantia/efectos de los fármacosRESUMEN
Hypnophilin and panepoxydone, terpenoids isolated from Lentinus strigosus, have significant inhibitory activity on Trypanosoma cruzi trypanothione reductase (TR). Although they have similar TR inhibitory activity at 10 µg/mL (40.3 µM and 47.6 µM for hypnophilin and panepoxydone, respectively; ~100%), hypnophilin has a slightly greater inhibitory activity (~71%) on T. cruzi amastigote (AMA) growth in vitro as well as on in vitro phytohemagglutinin (PHA)-induced peripheral blood mononuclear (PBMC) proliferation (~70%) compared to panepoxydone (69% AMA inhibition and 91% PBMC inhibition). Hypnophilin and panepoxydone at 1.25 µg/mL had 67% inhibitory activity onLeishmania (Leishmania) amazonensis amastigote-like (AMA-like) growth in vitro. The panepoxydone activity was accompanied by a significant inhibitory effect on PHA-induced PBMC proliferation, suggesting a cytotoxic action. Moreover, incubation of human PBMC with panepoxydone reduced the percentage of CD16(+) and CD14(+) cells and down-regulated CD19(+), CD4(+) and CD8(+) cells, while hypnophilin did not alter any of the phenotypes analyzed. These data indicate that hypnophilin may be considered to be a prototype for the design of drugs for the chemotherapy of diseases caused by Trypanosomatidae.
Asunto(s)
Antiprotozoarios/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Leishmania/efectos de los fármacos , Lentinula/química , Extractos Vegetales/farmacología , Sesquiterpenos/farmacología , Trypanosoma cruzi/efectos de los fármacos , Antígenos CD/efectos de los fármacos , Compuestos Bicíclicos Heterocíclicos con Puentes/aislamiento & purificación , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Sesquiterpenos/aislamiento & purificaciónRESUMEN
Hypnophilin and panepoxydone, terpenoids isolated from Lentinus strigosus, have significant inhibitory activity onTrypanosoma cruzi trypanothione reductase (TR). Although they have similar TR inhibitory activity at 10 μg/mL (40.3 μM and 47.6 μM for hypnophilin and panepoxydone, respectively; ~100 percent), hypnophilin has a slightly greater inhibitory activity (~71 percent) on T. cruzi amastigote (AMA) growth in vitro as well as on in vitro phytohemagglutinin (PHA)-induced peripheral blood mononuclear (PBMC) proliferation (~70 percent) compared to panepoxydone (69 percent AMA inhibition and 91 percent PBMC inhibition). Hypnophilin and panepoxydone at 1.25 μg/mL had 67 percent inhibitory activity onLeishmania (Leishmania) amazonensis amastigote-like (AMA-like) growth in vitro. The panepoxydone activity was accompanied by a significant inhibitory effect on PHA-induced PBMC proliferation, suggesting a cytotoxic action. Moreover, incubation of human PBMC with panepoxydone reduced the percentage of CD16+ and CD14+ cells and down-regulated CD19+, CD4+ and CD8+ cells, while hypnophilin did not alter any of the phenotypes analyzed. These data indicate that hypnophilin may be considered to be a prototype for the design of drugs for the chemotherapy of diseases caused by Trypanosomatidae.
Asunto(s)
Humanos , Antiprotozoarios/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Leishmania/efectos de los fármacos , Lentinula/química , Extractos Vegetales/farmacología , Sesquiterpenos/farmacología , Trypanosoma cruzi/efectos de los fármacos , Antígenos CD/efectos de los fármacos , Compuestos Bicíclicos Heterocíclicos con Puentes/aislamiento & purificación , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos , Leucocitos Mononucleares/efectos de los fármacos , Sesquiterpenos/aislamiento & purificaciónRESUMEN
BACKGROUND/AIMS: The aims were to estimate among patients with hepatitis C virus (HCV) infection the prevalence of alcohol and coffee intake and smoking habit, the reliability of these self-reported data and the possible change of patients' habit after their first contact with a Viral Hepatitis Service. METHODS: 229 patients were initially interviewed personally at the Viral Hepatitis Service and after 6 months they were re-interviewed by phone in regard to their alcohol, coffee drinking and smoking habits. RESULTS: Alcohol drinkers were 55.5% of males and 35.3% of females. Most subjects drank coffee daily, both men (90.0%) and women (84.9%). The proportion of current smokers was higher in males (43.6%) than females (26.9%). We found a fair to good reliability of self-reported data regarding patients' habits, alcohol and coffee intake, and number of cigarettes smoked daily. We observed a statistically significant decrease in alcohol and coffee intake and cigarettes smoked between baseline and follow-up interviews. CONCLUSION: We found a fairly high proportion of HCV-infected patients who regularly drink alcohol and coffee beverages and smoke cigarettes, especially among males. The reliability of self-reported data on these habits seems satisfactory. More decisive action to modify these habits, especially alcohol intake, is required in these patients.
Asunto(s)
Consumo de Bebidas Alcohólicas , Café , Hepatitis C/fisiopatología , Estilo de Vida , Fumar , Adulto , Anciano , Consumo de Bebidas Alcohólicas/efectos adversos , Café/efectos adversos , Progresión de la Enfermedad , Femenino , Humanos , Italia , Masculino , Persona de Mediana Edad , Fumar/efectos adversos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Piperaceae is a family of tropical plants known to have antifungal, antibacterial, tumour-inhibitory, antiviral, antioxidant, molluscicidal and leishmanicidal activities. In this work, extracts and fractions from aerial parts of Piper abutiloides (Piperaceae), a traditional medicinal plant, were evaluated against the fungal species Candida albicans, C. parapsilosis, C. krusei, C. glabrata, C. tropicalis, Cryptococcus neoformans and Sporothrix schenckii. The results have shown that the antifungal activity of this plant can be concentrated in the hexanic fraction after partitioning its hydroalcoholic extract between hexane and 90% aqueous methanol. The chromatographic fractionation of the bioactive part was monitored with a bioautographic assay using C. glabrata, and allowed the isolation of three antifungal compounds: pseudodillapiol, eupomatenoid-6 and conocarpan. These compounds presented different potencies against the fungi tested, with the strongest effect being observed for eupomatenoid-6 against C. glabrata, which presented a minimal inhibitory concentration value of 0.3 microg spot(-1). Conocarpan showed antifungal activity without apparent cytotoxic effect on normal human lymphocytes, as assessed by the proliferation assay with human peripheral blood mononuclear cells stimulated with phytohaemaglutinin. This work reveals for the first time the occurrence of these compounds in P. abutiloides and justifies further studies to clarify their mechanisms of action.
Asunto(s)
Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Cryptococcus neoformans/efectos de los fármacos , Piper/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Sporothrix/efectos de los fármacos , Adulto , Antifúngicos/toxicidad , Benzofuranos/aislamiento & purificación , Benzofuranos/farmacología , Benzofuranos/toxicidad , Fraccionamiento Químico/métodos , Cromatografía/métodos , Femenino , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Masculino , Pruebas de Sensibilidad Microbiana , Fenoles/aislamiento & purificación , Fenoles/farmacología , Fenoles/toxicidad , Extractos Vegetales/toxicidad , Adulto JovenRESUMEN
In the last few years chlorine dioxide has been increasingly used for disinfecting drinking water in many countries. Although it does not react with humic substances, chlorine dioxide added to water is reduced primarily to chlorite and chlorate ions, compounds that are under investigation for their potential adverse effects on human health. The aim of this research was to study the genotoxicity of chlorite and chlorate and their mixtures. The end-points included two plant tests (chromosomal aberration test in Allium cepa and micronucleus assay in Tradescantia, carried out at different times of exposure) and two genotoxicity tests in human HepG2 cells (comet assay and cytokinesis-blocked micronucleus test). Preliminary toxicity tests were carried out for both plant and HepG2 assays. The results showed that chlorite and chlorate are able to induce chromosomal damage to plant systems, particularly chromosomal aberrations in A. cepa root tip cells, even at concentrations lower than the limit established by Italian normative law and WHO guidelines. In HepG2 cells increased DNA damage was only observed for chlorate at the lowest concentration. No increase in micronuclei frequency was detected in any of the samples tested in human HepG2 cells.
Asunto(s)
Cloratos/toxicidad , Cloruros/toxicidad , Daño del ADN , Bioensayo/métodos , Línea Celular Tumoral , Cromosomas de las Plantas/efectos de los fármacos , Cromosomas de las Plantas/genética , Ensayo Cometa/métodos , Humanos , Pruebas de Micronúcleos/métodos , Pruebas de Mutagenicidad/métodos , Cebollas/efectos de los fármacos , Cebollas/genética , Tradescantia/efectos de los fármacos , Tradescantia/genéticaRESUMEN
The Allium cepa assay is an efficient test for chemical screening and in situ monitoring for genotoxicity of environmental contaminants. The test has been used widely to study genotoxicity of many pesticides revealing that these compounds can induce chromosomal aberrations in root meristems of A. cepa. Pesticide residues can be present in fruit and vegetables and represent a risk for human health. The mutagenic and carcinogenic action of herbicides, insecticides and fungicides on experimental animals is well known. Several studies have shown that chronic exposure to low levels of pesticides can cause birth defects and that prenatal exposure is associated with carcinogenicity. This study evaluated the potential application of plant genotoxicity tests for monitoring mutagens in edible vegetables. The presence of pesticides and genotoxic compounds extracted from 21 treated vegetables and eight types of grapes sampled from several markets in Campania, a region in Southern Italy, was monitored concurrently. The extracts were analysed for pesticides by gas chromatography and high-performance liquid chromatography, and for genotoxicity using two plant tests: the micronucleus test and the chromosomal aberration test in A. cepa roots. Thirty-three pesticides were detected, some of which are not approved. Genotoxicity was found in some of the vegetables and grapes tested. Allium cepa tests proved to be sensitive in monitoring genotoxicity in food extracts. The micronucleus test in interphase cells gave a much higher mutagenicity than the chromosomal aberration test in anaphase-telophase cells.
Asunto(s)
Aberraciones Cromosómicas/inducido químicamente , Contaminación de Alimentos/análisis , Cebollas/genética , Residuos de Plaguicidas/toxicidad , Pruebas de Micronúcleos/métodos , Cebollas/efectos de los fármacos , Residuos de Plaguicidas/análisis , Plaguicidas , Extractos Vegetales/toxicidad , Verduras/química , Vitis/químicaRESUMEN
Disinfection of surface drinking water, in particular water chlorination, results in many by-products with potential genotoxic and/or carcinogenic activity. In the present study, we evaluated the genotoxicity of surface water after treatment with different disinfectants by means of in situ plant genotoxicity assays (micronucleus and chromosomal aberration tests) which can detect both clastogenic and aneugenic effects. The study was carried out at a pilot plant using lake water after sedimentation and filtration. This water supplied four stainless steel basins: three basins were disinfected with sodium hypochlorite, chlorine dioxide, and peracetic acid and the fourth basin containing untreated lake water was used as a control. Plants were exposed in situ in the basins. The study was carried out using water collected in different seasons over a period of about 1 year in order to assess the treatments in different physical and chemical lake water conditions. The micronucleus test in root cells of Vicia faba (Vicia faba/MCN test) revealed genotoxicity in many samples of disinfected water. The micronucleus test in Tradescantia pollen cells and the chromosome aberration test in root cells of Allium cepa showed genotoxic effects only in some disinfected samples, but also revealed genotoxicity in raw water. The results of the study indicated that the Vicia faba/MCN test was the most sensitive plant assay for disinfected water and that peracetic acid disinfection produced similar or lower genotoxicity than sodium hypochlorite or chlorine dioxide treatment.
Asunto(s)
Desinfectantes/efectos adversos , Agua Dulce/química , Pruebas de Mutagenicidad/métodos , Compuestos de Cloro/efectos adversos , Aberraciones Cromosómicas , Cromatografía de Gases y Espectrometría de Masas/métodos , Pruebas de Micronúcleos , Cebollas/efectos de los fármacos , Óxidos/efectos adversos , Ácido Peracético/efectos adversos , Raíces de Plantas/efectos de los fármacos , Plantas/efectos de los fármacos , Plantas/genética , Hipoclorito de Sodio/efectos adversos , Tradescantia/efectos de los fármacos , Tradescantia/genética , Vicia faba/efectos de los fármacos , Vicia faba/genética , Purificación del Agua/métodosRESUMEN
This study monitored the release of mutagenic/carcinogenic compounds into mineral water (natural and carbonated) from polyethylene terephthalate (PET) bottles, using a plant mutagenicity test which reveals micronuclei formation in Tradescantia pollen cells (Trad/MCN test), a DNA damage assay (Comet assay) on human leukocytes and gas chromatography/mass spectrometry (GC/MS) for the characterisation of migrants. The water samples were collected at a bottling plant and stored in PET bottles for a period ranging from 1 to 12 months. Every month some samples were randomly collected and lyophilised, the residual powders were extracted with organic solvents and then analysed by GC/MS and tested for DNA damage in human leukocytes, or reconstituted with distilled water to obtain concentrates for the exposure of Tradescantia inflorescences. Micronuclei increase in pollen was found only in natural mineral water stored for 2 months. DNA-damaging activity was found in many of the natural and carbonated water samples. Spring water was negative in the plant micronuclei test and the Comet assay, whereas distributed spring water showed DNA-damaging effects, suggesting a possible introduction of genotoxins through the distribution pipelines. GC/MS analysis showed the presence in mineral water of di(2-ethylhexyl)phthalate, a nongenotoxic hepatocarcinogenic plasticizer, after 9 months of storage in PET bottles.
Asunto(s)
Carcinógenos/análisis , Aguas Minerales , Mutágenos/análisis , Tereftalatos Polietilenos/química , Embalaje de Productos , Ensayo Cometa , Commelinaceae/genética , Daño del ADN , Cromatografía de Gases y Espectrometría de Masas , Humanos , Leucocitos , PolenRESUMEN
Polygonum punctatum (Polygonaceae) is an herb known in some regions of Brazil as "erva-de-bicho" and is used to treat intestinal disorders. The dichloromethane extract of the aerial parts of this plant showed strong activity in a bioautographic assay with the fungus Cladosporium sphaerospermum. The bioassay-guided chemical fractionation of this extract afforded the sesquiterpene dialdehyde polygodial as the active constituent. The presence of this compound with antibiotic, anti-inflammatory and anti-hyperalgesic properties in "erva-de-bicho" may account for the effects attributed by folk medicine to this plant species.
Asunto(s)
Antifúngicos/farmacología , Cladosporium/efectos de los fármacos , Polygonum/química , Sesquiterpenos/farmacología , Antifúngicos/química , Brasil , Extractos Vegetales/química , Extractos Vegetales/farmacología , Sesquiterpenos/químicaRESUMEN
In this study, we screened sixty medicinal plant species from the Brazilian savanna ("cerrado") that could contain useful compounds for the control of tropical diseases. The plant selection was based on existing ethnobotanic information and interviews with local healers. Plant extracts were screened for: (a) molluscicidal activity against Biomphalaria glabrata, (b) toxicity to brine shrimp (Artemia salina L.), (c) antifungal activity in the bioautographic assay with Cladosporium sphaerospermum and (d) antibacterial activity in the agar diffusion assay against Staphylococcus aureus, Escherichia coli, Bacillus cereus and Pseudomonas aeruginosa. Forty-two species afforded extracts that showed some degree of activity in one or more of these bioassays.
Asunto(s)
Antibacterianos/aislamiento & purificación , Antifúngicos/aislamiento & purificación , Moluscocidas/aislamiento & purificación , Plantas Medicinales/química , Animales , Artemia/efectos de los fármacos , Biomphalaria/efectos de los fármacos , Brasil , Cladosporium/efectos de los fármacos , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Extractos Vegetales/uso terapéuticoRESUMEN
An extract of the aerial parts from Alomia myriadenia Schultz-Bip. ex Baker (Asteraceae) showed significant cytotoxicity against a panel of human cancer cell lines in a screening of extracts from Brazilian Atlantic Forest plant species. Employing a bioassay-linked HPLC-electrospray/MS method, followed by semi-preparative HPLC, the active component was isolated and characterized as a mixture of epimers of the labdane diterpene 12S,16-dihydroxy-ent-labda-7,13-dien-15,16-olide.
Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Asteraceae/química , Diterpenos/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Cromatografía Líquida de Alta Presión , Diterpenos/química , Diterpenos/farmacología , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Extractos Vegetales/química , Hojas de la Planta/química , Células Tumorales CultivadasRESUMEN
The Tradescantia/micronuclei test (TRAD/MCN) is a well-validated test for monitoring environmental genotoxicants. These pollutants induce at the early meiotic stage of pollen mother cells chromosome fragments which become micronuclei at the tetrad stage. The standard test protocol requires some hours of exposure of the inflorescences and a recovery time of about 24 hours to reach the early tetrad stage. Since the recovery period represents a critical step of the TRAD/MCN, experiments were performed to establish its length in plants of clone #4430 of the hybrid T. hirsutiflora x T. subacaulis which is widely used in environmental monitoring. The aim of the present research was to ascertain the exact duration of recovery time in order to improve the sensitivity of the TRAD/MCN test. First, studies were performed to select the flowers at the beginning of the meiosis, and then anthers were sampled and studied for a period of 48-86 hours. The complete meiosis in the plants examined required about 80 hours. Second, exposure to genotoxic substances followed by different recovery times was carried out to demonstrate that effectiveness of the TRAD/MCN test is closely related to the duration of the recovery time. The test was carried out by exposing inflorescences to known mutagens (sodium azide and maleic hydrazide) for six hours followed by different recovery times (24-72 hours). The results showed that the frequency of micronuclei in the pollen mother cells increased with the length of the recovery time.
Asunto(s)
Monitoreo del Ambiente/métodos , Contaminantes Ambientales/farmacología , Liliaceae/genética , Pruebas de Micronúcleos , Polen/efectos de los fármacos , Cromosomas/efectos de los fármacos , Contaminantes Ambientales/análisis , Liliaceae/efectos de los fármacos , Meiosis , Polen/citología , Reproducibilidad de los ResultadosRESUMEN
The dichloromethane-methanol extract from the fresh leaves of Trixis vauthieri DC (Asteraceae) afforded trixol, a new cyclohexadecane derivative. The structural elucidation of this new compound, with a novel skeleton, was based on NMR studies of the natural product nd its derivatives.
Asunto(s)
Asteraceae/química , Hidrocarburos Cíclicos/síntesis química , Espectroscopía de Resonancia Magnética , Extractos Vegetales/química , Hojas de la Planta/químicaRESUMEN
Ethanol extracts of 83 plants species belonging to the Asteraceae (Compositae) family, collected in the State of Minas Gerais, Brazil, were tested for larvicidal activity against the mosquito Aedes fluviatilis--Diptera: Culicidae). The extract from Tagetes minuta was the most active with a LC90 of 1.5 mg/l and LC50 of 1.0 mg/l. This plant has been the object of several studies by other groups and its active components have already been identified as thiophene derivatives, a class of compounds present in many Asteraceae species. The extract of Eclipta paniculata was also significantly active, with a LC90 of 17.2 mg/l and LC50 of 3.3 mg/l and no previous studies on its larvicidal activity or chemical composition could be found in the literature. Extracts of Achryrocline satureoides, Gnaphalium spicatum, Senecio brasiliensis, Trixis vauthieri, Tagetes patula and Vernonia ammophila were less active, killing more than 50% of the larvae only at the higher dose tested (100 mg/l).
Asunto(s)
Aedes/efectos de los fármacos , Larva/efectos de los fármacos , Control de Mosquitos/métodos , Extractos Vegetales/farmacología , AnimalesRESUMEN
The hexane extract from leaves of Vernonia brasiliana (L.) Druce (Compositae) was active in vitro against Plasmodium falciparum and in vivo in mice infected with Plasmodium berghei. This extract was subjected to a bioassay-guided fractionation protocol based on the in vitro model. Lupeol was identified as a compound responsible for the activity, inhibiting the P.falciparum growth by 45% when tested at 25 micrograms/ml. However, this triterpene was inactive in vivo when 15 mg/kg were administered per os during four consecutive days to mice infected with P.berghei. beta-Amyrin and germanicol, isolated from the same fraction that yielded lupeol, were inactive in the in vitro assay.
Asunto(s)
Antimaláricos/farmacología , Plantas/química , Triterpenos/farmacología , Animales , Antimaláricos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Femenino , Ratones , Plasmodium berghei/efectos de los fármacos , Plasmodium falciparum/efectos de los fármacos , Triterpenos/aislamiento & purificaciónRESUMEN
The diterpene ent-kaur-16-en-19-oic acid (1) was identified as the trypanocidal component of the ethanolic extract from Mikania obtusata D. C. (Asteraceae). This compound presents an IC50 of 0.5 mg/ml (1.66 mM) against the trypomastigote blood form of the Trypanosoma cruzi, the causative agent of Chagas' disease (American trypanosomiasis).
Asunto(s)
Diterpenos/farmacología , Plantas/química , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , RatonesRESUMEN
With the aim of finding an acceptable method for selecting plant extracts to be assayed against the infective blood form of Trypanosoma cruzi, the causative agent of Chagas' disease (American trypanosomiasis), two different strategies were compared: a) screening only medicinal species and b) pre-screening random collected species in the brine shrimp lethality assay (BSLA). Fifty-two plants belonging to the Asteraceae family, including eighteen medicinal species, were collected and their ethanol extracts assayed against both T. cruzi and Artemia salina (brine shrimp). The proportion of trypanocidal extracts among the medicinal species and among the random collection did not differ significantly. On the other hand, the proportion of trypanocidal extracts among those that presented LC(50) of less than 100 ppm to A. salina was four times higher than among the medicinal species.