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1.
Pest Manag Sci ; 76(11): 3693-3701, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32453460

RESUMO

BACKGROUND: Disease vector insects are barriers for human development. The use of synthetic chemicals to control these vectors has caused damage to the environment and contributed to the arising of resistant insect populations. This has led to an increased search for plant-derived molecules with insecticidal activity or that show synergistic effects with known insecticidal substances, such as protease inhibitors. Thus, we aimed to evaluate the effect of Enterolobium contortisiliquum trypsin inhibitor (EcTI) on Aedes aegypti development as well as its effect on insecticidal activity of Bacillus thuringiensis toxins. RESULTS: EcTI showed an apparent molecular mass about of 20 kDa in SDS-PAGE and was able to inhibit in vitro the activity of trypsin and proteases from midgut of Ae. aegypti larvae. EcTI was not able to cause acute toxicity on mosquito larvae even at 1000 µg mL-1 , however it promoted a delay in larval development after prolonged exposure. The zymogram results for EcTI-treated larvae (from 50 to 200 µg mL-1 ) showed an increase of midgut proteases activity as a larvae defense mechanism, however no changes in the enzyme profile was observed. These same concentrations were able to enhance up to three fold the insecticidal activity of B. thuringiensis toxins without causing toxicity to Artemia sp. nauplii, a non-target organism. CONCLUSIONS: The results offer a novel approach by combining EcTI and B. thuringiensis toxins for combating Ae. aegypti larvae. © 2020 Society of Chemical Industry.


Assuntos
Aedes , Bacillus thuringiensis , Animais , Larva , Mosquitos Vetores , Sementes , Inibidores da Tripsina/farmacologia
2.
J Toxicol Environ Health A ; 83(4): 135-152, 2020 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-32114934

RESUMO

Triplaris gardneriana Wedd. is a tree used in folk medicine to treat venereal diseases and inflammation as well as a source of biological compounds with antioxidant capacity. In order to assess the safety of these bioactive compounds, the present study aimed to determine the toxicity of an ethanolic extract of T. gardneriana, (EETg). Toxicological tests included hemolytic activity, toxicity toward the brine shrimp Artemia, cytotoxicity against breast cancer cells (MCF7) and acute oral toxicity in rodents. In addition, toxicogenomics techniques were used to determine genome expression in MCF7 cells exposed to EETg. The results showed that the extract exhibits approximately 60% of hemolytic activity at the highest tested concentration (64 µg/ml) and toxicity against nauplii of Artemia sp. (LC50 of 67.85 µg/ml). Further, EETg appears to be cytotoxic to MCF7 (cell viability reduced to 40% at 250 µg/ml after 24 hr). Genomic data demonstrated differential expression of 14 genes. Data analysis indicated possible altered pathways (e.g., xenobiotic metabolism), possible adverse health risks (e.g., hepatotoxicity), and drugs with similar gene expression profile (e.g., antimicrobials). The investigation provides important information on potentially adverse aspects of EETg, which need to be considered prior to the therapeutic utilization of this plant.Abbreviations: EETg: ethanolic extract of T. gardneriana seeds; MCF7: michigan cancer foundation-7 which refers to a human breast cell line (adenocarcinoma); NGS: next-generation sequencing; edgeR: empirical analysis of digital gene expression data in R; Consensus: consensus path database; FDR: false discovery rate; NCBI: national center for biotechnology information; KEGG: kyoto encyclopedia of genes and genomes; Ingenuity: ingenuity pathway analysis software; CMAP: connectivity map; OECD: organization for economic co-operation and development; HL-60: human promyelocytic leukemia cells; PC3: prostate cancer cells.


Assuntos
Hemólise/efeitos dos fármacos , Extratos Vegetais/toxicidade , Polygonaceae/química , Sementes/química , Adulto , Animais , Artemia , Sobrevivência Celular/efeitos dos fármacos , Etanol/química , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos , Extratos Vegetais/química , Transcriptoma , Aumento de Peso/efeitos dos fármacos , Adulto Jovem
3.
Environ Toxicol ; 35(8): 849-860, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32170993

RESUMO

The zebrafish (Danio rerio) is a small teleost fish that is becoming increasingly popular in laboratories worldwide and several attributes have also placed the zebrafish under the spotlight of (eco)toxicological studies. Since the 1990s, international organizations such as ISO and OECD have published guidelines for the use of zebrafish in ecotoxicological assessment of environmental toxicants such as the Fish Embryo Acute Toxicity (FET) test, OECD n° 236 guideline. This protocol uses 3,4-dichloroaniline (DCA), an aniline pesticide whose toxicity to fish species at early life stages is well known, as a positive control. Despite its use, little is known about its molecular mechanisms, especially in the context of the FET test. Therefore, this study aimed to investigate such changes in zebrafish larvae exposed to DCA (4 mg/L) for 96 hours using gel-free proteomics. Twenty-four proteins detected in both groups were identified as significantly affected by DCA exposure, and, when considering group-specific entities, 48 proteins were exclusive to DCA (group-specific proteins) while 248 were only detected in the control group. Proteins modulated by DCA treatment were found to be involved in metabolic processes, especially lipids and hormone metabolism (eg, Apoa1 and Apoa1b and vitelogenins), as well as proteins important for developmental processes and organogenesis (eg, Myhc4, Acta2, Sncb, and Marcksb). The results presented here may therefore provide a better understanding of the relationships between molecular changes and phenotype in zebrafish larvae treated with DCA, the reference compound of the FET test.


Assuntos
Compostos de Anilina/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ecotoxicologia , Embrião de Mamíferos , Embrião não Mamífero/metabolismo , Larva , Proteômica , Testes de Toxicidade Aguda , Peixe-Zebra/metabolismo
4.
Molecules ; 22(2)2017 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-28208654

RESUMO

Moringa oleifera has been used in traditional medicine to treat diabetes. However, few studies have been conducted to relate its antidiabetic properties to proteins. In this study, a leaf protein isolate was obtained from M. oleifera leaves, named Mo-LPI, and the hypoglycemic and antioxidant effects on alloxan-induced diabetic mice were assessed. Mo-LPI was obtained by aqueous extraction, ammonium sulphate precipitation and dialysis. The electrophoresis profile and proteolytic hydrolysis confirmed its protein nature. Mo-LPI showed hemagglutinating activity, cross-reaction with anti-insulin antibodies and precipitation after zinc addition. Single-dose intraperitoneal (i.p.) administration of Mo-LPI (500 mg/kg·bw) reduced the blood glucose level (reductions of 34.3%, 60.9% and 66.4% after 1, 3 and 5 h, respectively). The effect of Mo-LPI was also evidenced in the repeated dose test with a 56.2% reduction in the blood glucose level on the 7th day after i.p. administration. Mo-LPI did not stimulate insulin secretion in diabetic mice. Mo-LPI was also effective in reducing the oxidative stress in diabetic mice by a decrease in malondialdehyde level and increase in catalase activity. Mo-LPI (2500 mg/kg·bw) did not cause acute toxicity to mice. Mo-LPI is a promising alternative or complementary agent to treat diabetes.


Assuntos
Antioxidantes/farmacologia , Hipoglicemiantes/farmacologia , Moringa oleifera/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Proteínas de Plantas/farmacologia , Aloxano/efeitos adversos , Animais , Antioxidantes/química , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Hemaglutinação/efeitos dos fármacos , Hipoglicemiantes/química , Insulina/sangue , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Proteínas de Plantas/química , Coelhos
5.
Bioengineered ; 6(6): 323-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26513483

RESUMO

Insecticidal Cry proteins from Bacillus thuringiensis (Bt) have been exploited in the development of genetically modified (GM) crops for pest control. However, several pests are still difficult to control such as the coleopteran boll weevil Anthonomus grandis. By applying in vitro molecular evolution to the cry8Ka1 gene sequence, variants were generated with improved activity against A. grandis. Among them, Cry8Ka5 mutant protein showed coleoptericidal activity 3-fold higher (LC50 2.83 µg/mL) than that of the original protein (Cry8Ka1). Cry8Ka5 has been used in breeding programs in order to obtain coleopteran-resistant cotton plants. Nevertheless, there is some concern in relation to the food safety of transgenic crops, especially to the heterologously expressed proteins. In this context, our research group has performed risk assessment studies on Cry8Ka5, using the tests recommended by Codex as well as tests that we proposed as alternative and/or complementary approaches. Our results on the risk analysis of Cry8Ka5 taken together with those of other Cry proteins, point out that there is a high degree of certainty on their food safety. It is reasonable to emphasize that most safety studies on Cry proteins have essentially used the Codex approach. However, other methodologies would potentially provide additional information such as studies on the effects of Cry proteins and derived peptides on the indigenous gastrointestinal microbiota and on intestinal epithelial cells of humans. Additionally, emerging technologies such as toxicogenomics potentially will offer sensitive alternatives for some current approaches or methods.


Assuntos
Proteínas de Bactérias/genética , Endotoxinas/genética , Gossypium/genética , Gossypium/parasitologia , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/parasitologia , Animais , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/toxicidade , Endotoxinas/toxicidade , Inocuidade dos Alimentos , Proteínas Hemolisinas/toxicidade , Humanos , Resistência a Inseticidas , Conhecimento , Controle Biológico de Vetores , Medição de Risco , Gorgulhos/patogenicidade
6.
Nutrients ; 7(7): 6038-54, 2015 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-26205163

RESUMO

The biochemical and nutritional attributes of two soybean (Glycine max (L.) Merr.) cultivars, one susceptible (Seridó) and the other resistant (Seridó-RCH) to stem canker, were examined to assess whether the resistance to pathogens was related to levels of antinutritional and/or defense proteins in the plant and subsequently affected the nutritional quality. Lectin, urease, trypsin inhibitor, peroxidase and chitinase activities were higher in the resistant cultivar. Growing rats were fed with isocaloric and isoproteic diets prepared with defatted raw soybean meals. Those on the Seridó-RCH diet showed the worst performance in terms of protein quality indicators. Based on regression analysis, lectin, trypsin inhibitor, peroxidase and chitinase appear to be involved in the resistance trait but also in the poorer nutritional quality of Seridó-RCH. Thus, the development of cultivars for disease resistance may lead to higher concentrations of antinutritional compounds, affecting the quality of soybean seeds. Further research that includes the assessment of more cultivars/genotypes is needed.


Assuntos
Ração Animal/análise , Glycine max/metabolismo , Proteínas de Soja/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta , Regulação da Expressão Gênica de Plantas/fisiologia , Masculino , Valor Nutritivo , Ratos , Ratos Wistar , Proteínas de Soja/genética , Proteínas de Soja/farmacologia , Glycine max/genética , Aumento de Peso
7.
Food Chem Toxicol ; 83: 1-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26032632

RESUMO

Mo-CBP3 is an antifungal protein produced by Moringa oleifera which has been investigated as potential candidate for developing transgenic crops. Before the use of novel proteins, food safety tests must be conducted. This work represents an early food safety assessment of Mo-CBP3, using the two-tiered approach proposed by ILSI. The history of safe use, mode of action and results for amino acid sequence homology using the full-length and short contiguous amino acids sequences indicate low risk associated to this protein. Mo-CBP3 isoforms presented a reasonable number of alignments (>35% identity) with allergens in a window of 80 amino acids. This protein was resistant to pepsin degradation up to 2 h, but it was susceptible to digestion using pancreatin. Many positive attributes were presented for Mo-CBP3. However, this protein showed high sequence homology with allergens and resistance to pepsin digestion that indicates that further hypothesis-based testing on its potential allergenicity must be done. Additionally, animal toxicity evaluations (e.g. acute and repeated dose oral exposure assays) must be performed to meet the mandatory requirements of several regulatory agencies. Finally, the approach adopted here exemplified the importance of performing an early risk assessment of candidate proteins for use in plant transformation programs.


Assuntos
Antígenos de Plantas/efeitos adversos , Proteínas Alimentares/efeitos adversos , Alimentos Geneticamente Modificados/efeitos adversos , Modelos Moleculares , Moringa oleifera/metabolismo , Proteínas de Plantas/efeitos adversos , Sementes/metabolismo , Alérgenos/efeitos adversos , Alérgenos/química , Alérgenos/genética , Alérgenos/metabolismo , Ração Animal/efeitos adversos , Ração Animal/microbiologia , Animais , Antígenos de Plantas/química , Antígenos de Plantas/genética , Antígenos de Plantas/metabolismo , Brasil , Quitina/metabolismo , Proteínas Alimentares/química , Proteínas Alimentares/metabolismo , Digestão , Hipersensibilidade Alimentar/etiologia , Hipersensibilidade Alimentar/prevenção & controle , Alimentos Geneticamente Modificados/microbiologia , Humanos , Ligantes , Fungos Mitospóricos/crescimento & desenvolvimento , Moringa oleifera/genética , Controle Biológico de Vetores/métodos , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/efeitos adversos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Isoformas de Proteínas/efeitos adversos , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Medição de Risco , Sementes/genética , Homologia de Sequência de Aminoácidos
8.
An Acad Bras Cienc ; 84(1): 185-90, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22441608

RESUMO

Chagasin may be considered a potential plant-incorporated protectant (PIP) protein due to its deleterious effects on insect pests. However, extensive safety studies with PIP's are necessary before introducing them into the target plant. Thus, a short-term feeding trial in rats with high doses of r-chagasin was conducted to provide evidences about its safety. Three test diets containing casein + r-chagasin (0.25, 0.5 and 1% of total protein) were offered to rats (10 days). The test diets did not show adverse effects upon the development, organ weight, hematological parameters and serum protein profiles of rats, providing preliminary information on the safety of r-chagasin.


Assuntos
Ração Animal/toxicidade , Proteínas de Insetos/toxicidade , Tamanho do Órgão/efeitos dos fármacos , Animais , Proteínas de Insetos/administração & dosagem , Masculino , Modelos Animais , Controle Biológico de Vetores , Ratos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/toxicidade , Testes de Toxicidade/métodos , Aumento de Peso
9.
An. acad. bras. ciênc ; 83(3): 1045-1058, Sept. 2011. tab
Artigo em Inglês | LILACS | ID: lil-595533

RESUMO

This study assessed the antiproliferative and cytotoxic potential against tumor lines of ethanolic seed extracts of 21 plant species belonging to different families from Northeastern Brazil. In addition, some underlying mechanisms involved in this cytotoxicity were also investigated. Among the 21 extracts tested, the MTT assay after 72 h of incubation demonstrated that only the ethanolic extract obtained from Myracrodruon urundeuva seeds (EEMUS), which has steroids, alkaloids and phenols, showed in vitro cytotoxic activity against human cancer cells, being 2-fold more active on leukemia HL-60 line [IC50 value of 12.5 (9.5-16.7) μg/mL] than on glioblastoma SF-295 [IC50 of 25.1 (17.3-36.3) μg/mL] and Sarcoma 180 cells [IC50 of 38.1 (33.5-43.4) μg/mL]. After 72h exposure, flow cytometric and morphological analyses of HL-60-treated cells showed that EEMUS caused decrease in cell number, volume and viability as well as internucleosomal DNA fragmentation in a dose-dependent way, suggesting that the EEMUS triggers apoptotic pathways of cell death.


Este estudo avaliou o potencial antiproliferativo e citotóxico contra linhagens de células tumorais de extratos etanólicos de sementes de vinte e uma espécies vegetais pertencentes a diferentes famílias do Nordeste brasileiro. Além disso, alguns mecanismos subjacentes envolvidos nesta citotoxidade também foram investigados. Dentre os 21 extratos testados pelo ensaio do MTT após 72 h de incubação, apenas o extrato etanólico obtido a partir de sementes de Myracrodruon urundeuva (EEMUS), o qual apresentou traços de esteróides, alcalóides e fenóis em sua composição, demonstrou atividade citotóxica in vitro contra células tumorais humanas, sendo 2 vezes mais ativo sobre a linhagem leucêmica HL-60 [IC50 valor de 12,5 (9,5-16,7) μg/mL] do que sobre células de glioblastoma SF-295 [IC50 de 25,1 (17,3-36,3) μg/mL] e de sarcoma 180 [IC50 de 38,1 (33,5-43,4) μg/mL]. Após 72 h de exposição, as análises morfológicas e por citometria de fluxo de células HL-60 tratadas com EEMUS mostraram diminuição no número de células, seu volume e viabilidade, assim como fragmentação internucleosomal do DNA de forma dose-dependente, sugerindo que a ação antiproliferativa de EEMUS pode ser ativada por vias apoptóticas.


Assuntos
Animais , Humanos , Camundongos , Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Brasil , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Plantas Medicinais/classificação , Sementes/química
10.
An Acad Bras Cienc ; 83(3): 1045-58, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21779655

RESUMO

This study assessed the antiproliferative and cytotoxic potential against tumor lines of ethanolic seed extracts of 21 plant species belonging to different families from Northeastern Brazil. In addition, some underlying mechanisms involved in this cytotoxicity were also investigated. Among the 21 extracts tested, the MTT assay after 72 h of incubation demonstrated that only the ethanolic extract obtained from Myracrodruon urundeuva seeds (EEMUS), which has steroids, alkaloids and phenols, showed in vitro cytotoxic activity against human cancer cells, being 2-fold more active on leukemia HL-60 line [IC(50) value of 12.5 (9.5-16.7) µg/mL] than on glioblastoma SF-295 [IC(50) of 25.1 (17.3-36.3) µg/mL] and Sarcoma 180 cells [IC(50) of 38.1 (33.5-43.4) µg/mL]. After 72h exposure, flow cytometric and morphological analyses of HL-60-treated cells showed that EEMUS caused decrease in cell number, volume and viability as well as internucleosomal DNA fragmentation in a dose-dependent way, suggesting that the EEMUS triggers apoptotic pathways of cell death.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Brasil , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Humanos , Camundongos , Plantas Medicinais/classificação , Sementes/química
11.
An. acad. bras. ciênc ; 82(3): 585-594, Sept. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-556794

RESUMO

This study assessed the toxicity of seed water extracts of 15 leguminous species upon Aedes aegypti larvae. A partial chemical and biochemical characterization of water extracts, as well as the assessment of their acute toxicity in mice, were performed. The extracts of Amburana cearensis, Anadenanthera macrocarpa, Dioclea megacarpa, Enterolobium contortisiliquum and Piptadenia moniliformis caused 100 percent of mortalit y after 1 to 3 h of exposure. They showed LC50 and LC90 values ranging from 0.43 ± 0.01 to 9.06 ± 0.12 mg/mL and from 0.71 ± 0.02 to 13.03 ± 0.15 mg/mL, respectively. Among the secondary metabolite constituents, the seed water extracts showed tannins, phenols, flavones, favonols, xanthones, saponins and alkaloids. The extracts also showed high soluble proteins content (0.98 to 7.71 mg/mL), lectin (32 to 256 HU/mL) and trypsin inhibitory activity (3.64 = 0.43 to 26.19 = 0.05 gIT/kg of flour) The electrophoretic profiles showed a great diversity of protein bands, many of which already described as insecticide proteins. The extracts showed low toxicity to mice (LD50 > 0.15 = 0.01 g/kg body weight), but despite these promising results, further studies are necessary to understand the toxicity of these extracts and their constituentsfrom primary and secondary metabolism upon Ae. aegypti.


Este trabalho objetivou avaliar a toxicidade dos extratos aquosos de sementes de 15 espécies de leguminosas contra larvas de Aedes aegypti. Foi realizada uma caracterização química e bioquímica parcial dos extratos aquosos e a avaliação da toxicidade aguda em camundongos. Os extratos de Amburana cearensis, Anadenanthera macrocarpa, Dioclea megacarpa, Enterolobium contortisiliquum e Piptadenia moniliformis causaram 100 por cento de mortalidade depois de 1 a 3 h de exposição e mostraram valores de CL50 e CL90 entre 0,43 = 0,01 e 9,06 ± 0,12 e entre 0,71 = 0,02 e 13,03 = 0,15 mg/mL, respectivamente. Dentre os constituintes do metabolismo secundário, os extratos das sementes apresentaram taninos, fenóis, flavonas, flavonóis, xantonas, saponinas e alcalóides. Os extratos apresentaram alto teor de proteínas solúveis (0,98 to 7,71 mg/mL), lectina (32 to 256 UH/mL) e inibidor de tripsina (3,64 ± 0,43 to 26,19 = 0,05 gIT/kg de farinha). O perfil eletroforéticomostrou uma grande diversidade de proteínas, muitas dasquais já descritas como inseticidas. Os extratos mostraram baixa toxicidade ao camundongo (DL50 > 0,15 = 0,01 g/kg peso corporal), porém apesar desses resultados promissores, estudos posteriores são necessários para compreender a toxicidade desses extratos e de seus constituintes do metabolismo primário e secundário sobre Ae. aegypti.


Assuntos
Animais , Camundongos , Aedes/efeitos dos fármacos , Fabaceae , Inseticidas , Extratos Vegetais , Sementes , Fabaceae/química , Fabaceae/classificação , Larva/efeitos dos fármacos , Sementes/química , Testes de Toxicidade Aguda
12.
An Acad Bras Cienc ; 82(3): 585-94, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21562687

RESUMO

This study assessed the toxicity of seed water extracts of 15 leguminous species upon Aedes aegypti larvae. A partial chemical and biochemical characterization of water extracts, as well as the assessment of their acute toxicity in mice, were performed. The extracts of Amburana cearensis, Anadenanthera macrocarpa, Dioclea megacarpa, Enterolobium contortisiliquum and Piptadenia moniliformis caused 100% of mortalit y after 1 to 3 h of exposure. They showed LC(50) and LC(90) values ranging from 0.43 ± 0.01 to 9.06 ± 0.12 mg/mL and from 0.71 ± 0.02 to 13.03 ± 0.15 mg/mL, respectively. Among the secondary metabolite constituents, the seed water extracts showed tannins, phenols, flavones, favonols, xanthones, saponins and alkaloids. The extracts also showed high soluble proteins content (0.98 to 7.71 mg/mL), lectin (32 to 256 HU/mL) and trypsin inhibitory activity (3.64 = 0.43 to 26.19 = 0.05 gIT/kg of flour) The electrophoretic profiles showed a great diversity of protein bands, many of which already described as insecticide proteins. The extracts showed low toxicity to mice (LD(50) > 0.15 = 0.01 g/kg body weight), but despite these promising results, further studies are necessary to understand the toxicity of these extracts and their constituents from primary and secondary metabolism upon Ae. aegypti.


Assuntos
Aedes/efeitos dos fármacos , Fabaceae , Inseticidas , Extratos Vegetais , Sementes , Animais , Fabaceae/química , Fabaceae/classificação , Larva/efeitos dos fármacos , Camundongos , Sementes/química , Testes de Toxicidade Aguda
13.
J Am Mosq Control Assoc ; 25(3): 386-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19852234

RESUMO

Aedes aegypti is the major vector of 1 of the most concerning arboviruses of the world, the dengue fever. The only effective way of reducing the incidence of dengue fever is to control the vector mosquito, mainly by application of insecticides to its breeding places. This study was aimed at assessing the insecticidal activity of sodium anacardate, isolated from Brazilian cashew nut shell liquid (CNSL), against the eggs, 3rd instars or pupae of Ae. aegypti. In addition, the acute toxicity of sodium anacardate to mice was also investigated. Sodium anacardate showed toxicity against Ae. aegypti eggs (median effective concentration [EC50] = 162.93 +/- 29.93 microg/ml), larvae (median lethal concentration [LC50] = 55.47 +/- 3.0 microg/ml) and pupae (LC50 = 369.78 - 52.30 microg/ml). On the other hand, even at high dose (0.3 g/kg body weight), this compound did not cause any adverse effects on mice, suggesting that this compound is safe to mammals. Therefore, sodium anacardate may be a viable low-cost alternative to help combat Ae. aegypti.


Assuntos
Aedes/efeitos dos fármacos , Ácidos Anacárdicos/química , Ácidos Anacárdicos/farmacologia , Anacardium/química , Inseticidas/química , Inseticidas/farmacologia , Ácidos Anacárdicos/efeitos adversos , Animais , Relação Dose-Resposta a Droga , Inseticidas/efeitos adversos , Larva/efeitos dos fármacos , Camundongos , Óvulo/efeitos dos fármacos , Pupa/efeitos dos fármacos
14.
An Acad Bras Cienc ; 81(2): 207-16, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19488625

RESUMO

In this work, biological effects of the water extract of Moringa oleifera seeds (WEMOS) were assessed on eggs and 3rd instar larvae of Aedes aegypti and on its toxicity upon laboratory animals (Daphnia magna, mice and rats). Crude WEMOS showed a LC50 value of 1260microg/mL, causing 99.2 +/- 2.9% larvae mortality within 24 h at 5200microg/mL, though this larvicidal activity has been lost completely at 80 masculineC/10 min. WEMOS did not demonstrate capacity to prevent egg hatching. After extensive dialyses of the crude WEMOS into watersoluble dialyzable (DF) and nondyalizable (NDF) fractions, only DF maintained its efficacy to kill larvae. Acute toxicity evaluations on daphnids (EC50 of 188.7microg/mL) and mice (LD50 of 446.5 mg/kg body weight) pointed out to low toxicity. Despite the thymus hypertrophy, WEMOS revealed to be harmless in orally and subacutelytreated rats. In conclusion, WEMOS has thermostable bioactive compounds against Ae. aegypti larvae with apparent molecular mass lower than 12 kDa and moderately toxic potential.


Assuntos
Aedes/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Moringa oleifera/química , Extratos Vegetais/farmacologia , Animais , Larva/efeitos dos fármacos , Dose Letal Mediana , Camundongos , Óvulo/efeitos dos fármacos , Extratos Vegetais/toxicidade , Ratos , Ratos Wistar , Sementes/química , Fatores de Tempo
15.
An. acad. bras. ciênc ; 81(2): 207-216, June 2009. tab
Artigo em Inglês | LILACS | ID: lil-514655

RESUMO

In this work, biological effects of the water extract of Moringa oleifera seeds (WEMOS) were assessed on eggs and 3rd instar larvae of Aedes aegypti and on its toxicity upon laboratory animals (Daphnia magna, mice and rats). Crude WEMOS showed a LC50 value of 1260µg/mL, causing 99.2 ± 2.9 percent larvae mortality within 24 h at 5200µg/mL, though this larvicidal activity has been lost completely at 80ºC/10 min. WEMOS did not demonstrate capacity to prevent egg hatching. After extensive dialyses of the crude WEMOS into watersoluble dialyzable (DF) and nondyalizable (NDF) fractions, only DF maintained its efficacy to kill larvae. Acute toxicity evaluations on daphnids (EC50 of 188.7µg/mL) and mice (LD50 of 446.5 mg/kg body weight) pointed out to low toxicity. Despite the thymus hypertrophy, WEMOS revealed to be harmless in orally and subacutelytreated rats. In conclusion, WEMOS has thermostable bioactive compounds against Ae. aegypti larvae with apparent molecular mass lower than 12 kDa and moderately toxic potential.


Neste trabalho, o extrato aquoso das sementes de Moringaoleifera (EASMO) foi avaliado quanto aos seus efeitos biológicos sobre ovos e larvas de Aedes aegypti no 3ºestágio de desenvolvimento e sua toxicidade sobre animais de laboratório(Daphnia magna, camundongos e ratos). O EASMO bruto revelou uma CL50 de 1.260 µg/mL, causando 99, 2 ± 2, 9 por cento de mortalidade em 24 h na concentração de 5.200 µg/mL, embora o mesmo não tenha sido capaz de impedir a eclosão dos ovos. A atividade larvicida extinguiu-se após aquecimento do extrato a 80ºC/10 min. Diálises sucessivas do EASMO bruto resultaram em duas frações solúveis em água (Fração dializável, FD; Fração nãodializável, FND), dentre as quais apenas a FD mostrou ação larvicida. Testes de toxicidade aguda realizadosem dáfnias (CE50 de 188, 7 µg/mL) e camundongos (DL50 de446,5 mg/kg de peso corpóreo) evidenciaram baixa toxicidade. Apesar da hipertrofia tímica, o EASMO mostrou ser atóxicoapós tratamento subagudo via oral em ratos. Conclui-se, portanto, que o EASMO apresenta substâncias com capacida de larvicida contra Ae. aegypti, as quais possuem massa molecular aparente menor que 12 kDa e potencial tóxico moderado.


Assuntos
Animais , Camundongos , Ratos , Aedes/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Moringa oleifera/química , Extratos Vegetais/farmacologia , Larva/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Extratos Vegetais/toxicidade , Ratos Wistar , Sementes/química , Fatores de Tempo
16.
Rev. bras. farmacogn ; 19(2b): 586-591, abr.-jun. 2009. tab
Artigo em Português | LILACS | ID: lil-531828

RESUMO

Caesalpinia ferrea Mart. (jucá ou pau-ferro) é uma espécie da família Leguminosae cuja ocorrência estende-se da região Nordeste ao Estado do Rio de Janeiro. Trata-se de uma espécie bastante utilizada na medicina popular pelas suas inúmeras propriedades terapêuticas tais como antiinflamatória, analgésica, antimicrobiana e antitérmica as quais indicam a presença de compostos de interesse farmacológico. Contudo, muitos estudos em plantas também investigam a presença de compostos de interesse industrial. Com base nas propriedades terapêuticas e atividades já descritas para essa espécie, esse trabalho objetivou pesquisar atividades biológicas no extrato de sementes de C. ferrea na busca por compostos de interesse industrial e farmacológico. Os resultados indicaram a presença das atividades celulásica, amilásica, anticoagulante e larvicida contra A. aegypti no extrato aquoso das sementes de C. ferrea, entretanto, não foram observadas as atividades tóxica aguda, hemolítica, heparinásica, antibacteriana e antifúngica.


Caesalpinia ferrea Mart. is a species belonging to Leguminosae family commonly known in Brazil as "jucá" or "pau-ferro". It occurs in Brazil from the Northeast Region to the State of Rio de Janeiro and it is widely utilized in folk medicine due to its several therapeutic properties such as anti-inflammatory, analgesic, antimicrobial and antithermic, which indicate the presence of compounds of pharmacological interest. Besides, many studies with plants look for the presence of compounds with industrial applications. Based upon the therapeutic and bioactive properties described for this species so far, this work aimed to investigate several biological activities in the water extract of C. ferrea seeds. The results indicated the presence of the following activities: cellulase, amylase, anticoagulant and larvicide against A. aegypti in the water extract of C. ferrea seeds. Nevertheless, the extract did not show the other activities assayed: acute toxic activity, hemolytic, heparinasic, antibacterial and antifungal activities.

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