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1.
Ecotoxicol Environ Saf ; 182: 109448, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31398781

RESUMO

The electrocoagulation (EC) technique is an alternative method of isolating natural products with the advantage of minimizing the amounts of organic solvents required for this process, which are often harmful to the environment. In this research, the EC and the conventional solvent extraction methods were used in the isolation of Stemona alkaloids from the aerial parts of Stemona aphylla. A comparison was made between the amounts of the isolated alkaloids and the solvents used. The isolated alkaloids were evaluated for their larvicidal, ovicidal and oviposition-deterrent activities against the dengue vector, Aedes aegypti. The morphology and histopatology of the alkaloid treated larvae were also investigated. Two Stemona alkaloids, (2'S)-hydroxystemofoline and stemofoline, were isolated from both the EC and the conventional method. The amounts of (2'S)-hydroxystemofoline from the EC method was about the same as that obtained from the conventional method. However, the amounts of stemofoline obtained from the EC method were about two times larger than those obtained from the conventional method. Importantly, the EC method required six times less total organic solvents. The larvicidal activity assays of (2'S)-hydroxystemofoline and stemofoline showed that these were highly effective against Aedes aegypti larvae with LC50 values of 3.91 µg/ml and 4.35 µg/ml, respectively. Whereas, the crude EC extract (LC50 = 11.86 µg/ml) showed greater larvicidal activity than the crude extract obtained from the conventional extraction method (LC50 = 53.40 µg/ml). The morphological observations of the (2'S)-hydroxystemofoline and the stemofoline treated larvae revealed that the anal gills were the sites of aberrations. A histopathological study showed that larvae treated with these alkaloids had cytopathological alterations to the epithelial cells of the midgut. At a concentration 40 µg/ml (2'S)-hydroxystemofoline showed 100% ovicidal activity on 24 h old eggs while stemofoline showed 97.2%. Furthermore, the oviposition-deterrent effects of (2'S)-hydroxystemofoline and stemofoline, at a concentration of 80 µg/ml were 99.5% and 97.2%, respectively.


Assuntos
Aedes/efeitos dos fármacos , Alcaloides/toxicidade , Controle de Mosquitos/métodos , Componentes Aéreos da Planta/química , Extratos Vegetais/toxicidade , Stemonaceae/química , Animais , Dengue/transmissão , Vetores de Doenças , Eletrocoagulação , Feminino , Compostos Heterocíclicos de 4 ou mais Anéis , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Mosquitos Vetores , Oviposição/efeitos dos fármacos
2.
Bol. latinoam. Caribe plantas med. aromát ; 18(4): 359-377, jul. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1008174

RESUMO

Plant species have been used for therapeutic purposes since ancient times and are still in use today since these products represent a source of raw material for the production of phytotherapeutic formulations. Screening and investigation of plants with pharmacological potential require the evaluation of characteristics related to their action, efficacy and safety in different steps. Among these steps, pre- clinical trials are used to evaluate the properties of the test product in in vitro experiments, such as cytotoxicity assays. Within this context, this study consists of a bibliometric analysis of some in vitro cytotoxicity and toxicity assays in erythrocytes used during bioprospecting of medicinal plants. The results demonstrated the wide application of erythrocytes to evaluate the biological effects of medicinal plant extracts. The methods were found to be valid and effective for the preliminary investigation of the in vitro cytotoxicity and toxicity of plant products.


El uso de especies vegetales para fines terapéuticos es una práctica histórica y todavía bastante actual, ya que estos productos pueden representar una fuente de materia prima para la producción de formulaciones fitoterápicas. En investigación de plantas con potencial farmacológico requiere la evaluación de su acción, eficacia y seguridad, a través de diferentes etapas. Entre estas, en los ensayos preclínicos se evalúan las propiedades del producto-prueba en experimentos in vitro, tales como ensayos de citotoxicidad, entre otros. En este aspecto, el presente estudio consiste en un análisis bibliométrico acerca de algunas pruebas de citotoxicidad y toxicidad in vitro en eritrocitos realizados en los ensayos de bioprospección de plantas medicinales. Los resultados evidencian la amplia utilización de eritrocitos para la evaluación de los efectos biológicos de extractos de plantas medicinales, apuntándolos como métodos válidos y eficaces para la investigación preliminar de la citotoxicidad y toxicidad in vitro de productos vegetales.


Assuntos
Bioensaio/métodos , Extratos Vegetais/toxicidade , Eritrócitos/efeitos dos fármacos , Antioxidantes/toxicidade , Fragilidade Osmótica , Estresse Oxidativo , Eritrócitos/citologia , Bioprospecção , Hemólise/efeitos dos fármacos
3.
J Agric Food Chem ; 67(31): 8668-8676, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31271028

RESUMO

This study investigated the effect of Chlorella vulgaris (C. vulgaris) on genotoxicity, cytotoxicity, and apoptosis in Caco-2 and HT-29 cells. C. vulgaris significantly induced DNA damage in both cell lines at a concentration of 200 µg dry matter/mL (comet tail intensity CTI: 24.6 ± 4.7% for Caco-2, 16.6 ± 0.9% for HT-29). The application of processing (sonication, ball-milling) did not affect the genotoxicity negatively and lowered the lipid peroxidation in C. vulgaris preparations. C. vulgaris-induced intracellular formation of reactive oxygen species in human cell lines and might be responsible for the genotoxic effect. A solid fraction mainly triggered the observed DNA damage (CTI: 41.5 ± 1.9%), whereas a hydrophilic (CTI: 7.9 ± 1.7%) and lipophilic (CTI: 10.2 ± 2.1%) fraction revealed a significantly lower tail intensity. C. vulgaris significantly induced DNA damage in both cell lines possibly through intracellular formation of reactive oxygen species; however, it was repaired after a 2 h recovery time or was even avoided at lower concentrations. In addition, none of the preparations indicated an adverse effect on cell proliferation or revealed apoptotic activity.


Assuntos
Chlorella vulgaris/química , Dano ao DNA/efeitos dos fármacos , Células Epiteliais/citologia , Mutagênicos/toxicidade , Extratos Vegetais/toxicidade , Apoptose/efeitos dos fármacos , Processos Autotróficos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Chlorella vulgaris/crescimento & desenvolvimento , Chlorella vulgaris/efeitos da radiação , Ensaio Cometa , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Luz , Peroxidação de Lipídeos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
4.
Food Chem Toxicol ; 131: 110534, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31150781

RESUMO

Acute and subacute toxicities of the ethanol extract from Epigynum auritum (EAE) wereperformed by oral administration in pathogen-free mice. Acute toxicity study was performed at a single dose of 5000 mg/kg for 14 consecutive days, while subacute toxicity test was conducted by daily oral administration of EAE at doses of 312, 625, 1250, and 2500 mg/kg for 28 days. Acute toxicity study showed that LD50 of EAE was over 5000 mg/kg. The results of subacute toxicity showed no significant adverse effect of EAE at 312 mg/kg. Moreover, EAE exhibited toxicities to liver, spleen and kidney in mice determined by hematological, serum biochemical and histological analyses during daily oral administration of 1250 mg/kg and 2500 mg/kg EAE. The results revealed that the dose of EAE lower than 625 mg/kg can be regarded as safe.


Assuntos
Apocynaceae/química , Componentes Aéreos da Planta/química , Extratos Vegetais/toxicidade , Administração Oral , Animais , Relação Dose-Resposta a Droga , Etanol/química , Feminino , Rim/patologia , Fígado/patologia , Pulmão/patologia , Masculino , Camundongos Endogâmicos ICR , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Potássio/sangue , Sódio/sangue , Baço/patologia , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
5.
Food Chem Toxicol ; 131: 110538, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31152790

RESUMO

Dioscorea hispida var. daemona (Roxb) Prain & Burkill (DH), also known a tropical yam or intoxicating yam is a bitter wild tuber which is consumed as a staple food and traditionally used as a remedy in Malaysia. However, DH is also notorious for its intoxicating effects and there is currently a dearth of study of possible effects of DH on liver and placental tissues and hence its safe consumption warrants in-depth investigation. This study was therefore designed to investigate into the effect of DH on liver and placenta of pregnant rat via histopathological examination. Thirty pregnant Sprague-Dawley rats were randomly divided into five groups consisting of a control (distilled water) and four DH aqueous extract groups (250, 500, 1000 and 2000 mg/kg body weight). The extracts were administered via oral gavage daily throughout the study and animals were sacrificed on day 21. Paraffin-embedded, hematoxylin and eosin stained sections of placenta and liver were examined. Significant changes (p < 0.05) were observed on relative liver and placental weights of animals treated with 2000 mg/kg body weight DH extract. The placental numbers were decreased with the increased of DH extract concentration. Liver histological examination in all treated groups showed that tissues underwent degeneration characterized by hepatocyte swelling, cytoplasmic vacuolation, cytolysis, margination and clumping of nucleus chromatin. Changes of the basal and labyrinth zone were observed in placental tissues in all treated groups. Glycogen cells were reduced with fibrin deposition in the basal zone, while irregular vessel formation was demonstrated in the labyrinth zone. UHPLC-ESI-MS analysis showed the presence four steroidal saponins DH. In conclusion, DH aqueous extract exert hepatotoxicity and adverse effects on the placenta of rats. However, the underlying mechanism and phytochemicals inducing the observed toxicity require further investigation.


Assuntos
Dioscorea/química , Fígado/efeitos dos fármacos , Placenta/efeitos dos fármacos , Extratos Vegetais/toxicidade , Plantas Medicinais/química , Administração Oral , Animais , Feminino , Fígado/patologia , Tamanho do Órgão/efeitos dos fármacos , Placenta/patologia , Extratos Vegetais/administração & dosagem , Gravidez , Ratos Sprague-Dawley
6.
Food Chem Toxicol ; 131: 110535, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31154083

RESUMO

This study endeavours to investigate the phytochemical composition, biological properties and in vivo toxicity of methanol and dichloromethane extracts of Zaleya pentandra (L.) Jeffrey. Total bioactive contents, antioxidant (phosphomolybdenum and metal chelating, DPPH, ABTS, FRAP and CUPRAC) and enzyme inhibition (cholinesterases, tyrosinase α-amylase, and α-glucosidase) potential were assessed utilizing in vitro bioassays. UHPLC-MS phytochemical profiling was carried out to identify the essential compounds. The methanol extract was found to contain highest phenolic (22.60 mg GAE/g) and flavonoid (31.49 mg QE/g) contents which correlate with its most significant radical scavenging, reducing potential and tyrosinase inhibition. The dichloromethane extract was most potent for phosphomolybdenum, ferrous chelation, α-amylase, α-glucosidase, and cholinesterase inhibition assays. UHPLC-MS analysis of methanol extract unveiled to identify 11 secondary metabolites belonging to five sub-groups, i.e., phenolic, alkaloid, carbohydrate, terpenoid, and fatty acid derivatives. Additionally, in vivo toxicity was conducted for 21 days and the methanol extract at different doses (150, 200, 250 and 300 mg/kg) was administered in experimental chicks divided into five groups each containing five individuals. Different physical, haematological and biochemical parameters along with the absolute and relative weight of visceral body organs were studied. Overall, no toxic effect was noted for the extract at tested doses.


Assuntos
Aizoaceae/química , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Administração Oral , Animais , Galinhas , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/toxicidade , Depuradores de Radicais Livres/administração & dosagem , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/farmacologia , Depuradores de Radicais Livres/toxicidade , Metanol/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química
7.
Food Chem Toxicol ; 131: 110586, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31202939

RESUMO

Ginkgo biloba extract (GBE) is a popular botanical dietary supplement used worldwide and the safety of use is a public health concern. While GBE is a complex mixture, the terpene trilactones and flavonol glycosides are believed to elicit the pharmacological and/or toxicological effects of GBE. In a National Toxicology Program (NTP) 2-year rodent bioassay with GBE, hepatotoxicity was observed in rodents (≥100 mg/kg in rats, ≥ 200 mg/kg in mice). Subsequently, questions arose about whether or not the GBE used in NTP studies was representative of other GBE products and how rodent doses are related to human doses. To address these, we generated systemic exposure data for terpene trilactones in male rats following oral administration of 30, 100, and 300 mg/kg GBE test article from the 2-year bioassay. Dose-normalized Cmax and AUC∞ for terpene trilactones from the current study were within 5-fold of published rodent studies using a standardized GBE preparation. Comparison of our rat systemic exposure data at 100 mg/kg GBE to published human data following ingestion of 240 mg GBE-containing product showed that the rat/human exposure multiple was 3-22, for terpene trilactones. These data demonstrate the relevance of NTP rodent toxicity data to humans.


Assuntos
Ginkgo biloba/química , Extratos Vegetais/farmacocinética , Administração Oral , Animais , Flavonóis/sangue , Ginkgolídeos/sangue , Humanos , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/metabolismo , Extratos Vegetais/toxicidade , Ratos Endogâmicos F344 , Toxicocinética
8.
An Acad Bras Cienc ; 91(2): e20180468, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31241699

RESUMO

This study evaluates the antibacterial, cytotoxic activities, and phytochemical composition, of Callistemon citrinus, Hibiscus rosa-sinensis and Plumbago auriculata leaves and flowers, three ornamental plants in Mexico. However, in other countries offers a range of other uses. Ethanol extracts of C. citrinus leaf and flower presented stronger antibacterial activity than the extracts obtained from the other two plants. C. citrinus leaf showed low cytotoxicity (LC50 <600 µg/mL) on the brine shrimp test, whereas the ethanol extracts of H. rosa-sinensis and P. auriculata leaves showed no cytotoxic activity. Flower extracts obtained from the three plants did no exhibit cytotoxicity. GC-MS analysis revealed that the ethanol extract of P. auriculata leaf contained lupeol triterpene and lupeol acetate, neither of them have been previously reported in this genus. Gamma sitosterol was present in the leaf and flower extracts of P. auriculata. Higher contents of linoleic and linolenic acids were found in extracts of H. rosa-sinensis leaves and flowers. The ability of the ethanol extracts of C. citrinus leaves and flowers to inhibit the growth of Gram-positive and Gram-negative bacteria indicates a potentially broad antimicrobial spectrum. Moreover, the absence of cytotoxicity suggests the potential use of this plant to treat microbial infections.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hibiscus/química , Myrtaceae/química , Extratos Vegetais/farmacologia , Plumbaginaceae/química , Animais , Antibacterianos/toxicidade , Artemia/efeitos dos fármacos , México , Testes de Sensibilidade Microbiana , Extratos Vegetais/toxicidade , Testes de Toxicidade
9.
BMC Complement Altern Med ; 19(1): 150, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31242939

RESUMO

BACKGROUND: Traditional medicine remedies are commonly used for treatment of diverse ailments including bacterial infections. The activity against resistant bacteria and safety of some remedies sold as anti-infective treatments in market places in Buea, Southwest Cameroon were investigated as potential alternative treatment to counter increasing antibiotic resistance. METHODS: Ten remedies were purchased, their components documented and microbial load estimated. Methanol extracts of the remedies were tested for antibacterial activity by disc diffusion and microdilution. Cytotoxicity was evaluated on monkey kidney epithelial cells (LLC-MK2) while acute oral toxicity was done in BALB/c mice for the bactericidal extract. Extracts were further analysed using phytochemical tests. RESULTS: All the remedies had microbial loads above the acceptable limit of 105 CFU/g. The highest activity was produced by extracts of four remedies (TP 1, 2, 4, 6a, 6b) against all clinical isolates among which three were active against four control strains. Zones of inhibition ranged from 8 to 27 mm. Two of the four extracts produced zones ≥20 mm against multidrug resistant clinical isolates of Citrobacter freundii and Escherichia coli but were less active compared to Gentamycin positive control (P < 0.0001-0.0014). The most active extracts also recorded minimum inhibitory concentrations of 1 to 4 mg/mL. One of them (TP2) was bactericidal against a clinical isolate of methicillin-resistant Staphylococcus aureus with a minimum bactericidal concentration of 8 mg/mL. Extracts of six remedies did not show cytotoxicity and no mortality or adverse effect was recorded in the acute oral toxicity test. Phytochemical screening showed the most active extracts contained relatively high amounts of alkaloids and flavonoids. CONCLUSION: Only four of the eight remedies tested showed activity against multidrug resistant bacteria suggesting some of these remedies may not be effective against bacterial infections. Production and handling methods should be improved and the product quality controlled to ensure biosecurity. The remedies which were both active and non-toxic should be further investigated including in vivo experiments to assess their efficacy.


Assuntos
Antibacterianos/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/toxicidade , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Camarões , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Feminino , Humanos , Medicina Tradicional , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/toxicidade , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Plantas Medicinais/microbiologia
10.
BMC Complement Altern Med ; 19(1): 152, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253153

RESUMO

BACKGROUND: The leaves of Gongronema latifolium Benth. have long been recognized traditionally as a remedy for a variety of ailments in Africa. This study was conducted to evaluate the safety profile of the ethanolic extract of G. latifolium (GLES) leaves through a repeated dose 90-day oral toxicity study in male and female of Sprague Dawley rats. METHODS: GLES was orally administered at doses of 250, 500 and 1000 mg/kg/day consecutively for 90 days. RESULTS: No behavioral or physiological changes and mortality were observed. GLES did not have a marked impact on general hematological parameters and did not precipitate nephrotoxicity. However, compared to the control, serum triglycerides, total cholesterol and low-density lipoprotein levels were lower and white adipose tissue paired retroperitoneal fat depots were depleted in male rats treated with GLES3 by the end of the experiment. The liver was significantly enlarged in GLES-treated rats of both sexes. Negative gender-specific alterations were observed with the highest dose. Adverse risk was evident in the female rats mainly due to marked body weight gain and cerebrum weight reduction. CONCLUSION: Further research is needed to reach more specific conclusions about to the safety of ingesting high doses of GLES for long periods of time.


Assuntos
Apocynaceae/química , Extratos Vegetais/administração & dosagem , Tecido Adiposo Branco/efeitos dos fármacos , Administração Oral , Animais , Feminino , Fígado/efeitos dos fármacos , Masculino , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Folhas de Planta/química , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade
11.
BMC Complement Altern Med ; 19(1): 105, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31113420

RESUMO

BACKGROUND: The therapeutic use of Helleborus niger L. is manifold due to its specific phytochemical composition. Two compound groups, the ranunculin derivates including protoanemonin and the steroidal saponins, are also associated with toxicity (genotoxicity, disintegration of membrane structures). Therefore, in vitro investigations were performed on safety aspects of a Helleborus niger aqueous fermented extract (HNE). In addition its therapeutic potential against various cancer cell lines was assessed to gain insight into the respective mechanisms of action. METHODS: To evaluate the safe use of HNE, Ames and hemolytic tests were carried out. Two angiogenesis assays in 2D and 3D design were conducted to assess the anti-angiogenetic potential, for which human umbilical vein endothelial cells (HUVEC) were chosen. A panel of tumor cell lines was used in 2D and 3D proliferation assays as well in the migration- and invasion-assay. All investigations were performed with HNE compared to reference substances. The 2D proliferation assay was additionally performed with isolated compounds of HNE (characteristic steroidal saponins). RESULTS: HNE did not exhibit any genotoxic potential. Concentrations up to 10 µl/ml were classified as non-hemolytic. HNE exerted anti-angiogenetic effects in HUVEC and anti-proliferative effects in five cancer cell lines, whereas hellebosaponin A and D as well macranthosid I did not show comparable effects neither singly nor in combination. Due to the inherent instability of protoanemonin in isolated form, parallel investigations with protoanemonin could not be performed. HNE (600-1000 µg/ml) inhibited the migration of certain cancer cells by > 80% such as Caki-2, DLD-1 and SK-N-SH. CONCLUSION: HNE exhibit neither genotoxic nor hemolytic potential. The present investigations verify the anti-angiogenetic effects on HUVEC, the anti-proliferative effects and migration-inhibiting properties on tumor cells. The lower effect of the relevant steroidal saponins compared to the whole extract underlines the fact that the latter is more effective than a blend of isolated pharmacologically active components.


Assuntos
Antineoplásicos , Helleborus/química , Extratos Vegetais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Saponinas
12.
BMC Vet Res ; 15(1): 162, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31118023

RESUMO

BACKGROUND: Diarrhoea, a global economically important disease burden affecting swine and, especially piglets, is commonly caused by infection with entero-toxigenic E. coli (ETEC). Adherence of ETEC to porcine intestinal epithelial cells following infection, is necessary for its pathogenesis. While antimicrobials are commonly given as therapy or as feed additives for prophylaxis against microbial infections, the concern over increased levels of antimicrobial resistance necessitate the search for safe and effective alternatives in livestock feed. Attention is shifting to natural products including plants as suitable alternatives to antimicrobials. The activity of acetone crude leaf extracts of nine under-explored South African endemic plants from the Myrtaceae family with good antimicrobial activity were tested against pathogenic E. coli of porcine origin using a microplate serial dilution method. Bioautography, also with p-iodonitrotetrazolium violet as growth indicator was used to view the number of bioactive compounds in each extract. In vitro toxicity of extracts was determined against Caco-2 cells using the 3-(4,5-dimethythiazolyl-2)-2,5-diphenyltetrazolium bromide reduction assay. The antimicrobial susceptibility of E. coli isolates was tested on a panel of antimicrobials using the Kirby-Bauer agar diffusion method while the anti-adherence mechanism was evaluated using a Caco-2 cell enterocyte anti-adhesion model. RESULTS: The MIC of the extracts ranged from 0.07-0.14 mg/mL with S. legatii having the best mean MIC (0.05 mg/mL). Bioautography revealed at least two active bands in each plant extract. The 50% lethal concentration (LC50) values ranged between 0.03-0.66 mg/mL. Eugenia zeyheri least cytotoxic (LC50 = 0.66 mg/ml) while E. natalitia had the highest cytotoxicity (LC50 = 0.03 mg/mL). All the bacteria were completely resistant to doxycycline and colistin sulphate and many of the plant extracts significantly reduced adhesion of E. coli to Caco-2 cells. CONCLUSIONS: The extracts of the plants had good antibacterial activity as well as a protective role on intestinal epithelial cells against enterotoxigenic E. coli bacterial adhesion. This supports the potential use of these species in limiting infection causes by E. coli. Some of these plants or extracts may be useful as phytogenic feed additives but it has to be investigated by animal feed trials.


Assuntos
Antibacterianos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Eugenia/química , Extratos Vegetais/farmacologia , Syzygium/química , Acetona/química , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Humanos , Dose Letal Mediana , Testes de Sensibilidade Microbiana , Extratos Vegetais/toxicidade , Folhas de Planta/química
13.
Ecotoxicol Environ Saf ; 180: 565-574, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31129435

RESUMO

Natural pesticides are considered a good alternative to synthetic pesticides to reduce environmental impacts. However, biopesticides may have unknown effects on the environment, and can affect non-target organisms. In this study, the ecotoxicological effects of an aqueous extract (hydrolate) from Spanish populations of Artemisia absinthium (var. Candial) showing a promising biopesticide activity, were evaluated on non-target soil organisms from different trophic levels (natural microbial communities characterized through 16S rRNA gene sequencing, the earthworm Eisenia fetida and the plant Allium cepa). The hydrolate usually was considered as a by-product of the distillation to obtain essential oils. However, recently has been found to have nematicide properties. The hydrolate caused acute toxicity at values of LC50 of 3.87% v/v for A. cepa and 0.07 mL/g for E. fetida. All the concentrations except for the most diluted (1% v/v) reduced the bacterial physiological activity compared to controls (LC50 = 25.72% v/v after 24 h of exposure). The hydrolate also slightly altered the ability of the microbial community to degrade carbon substrates. These results indicate that the hydrolate from A. absinthium may affect the survival and metabolic abilities of key soil organisms.


Assuntos
Artemisia absinthium , Agentes de Controle Biológico/toxicidade , Praguicidas/toxicidade , Solo , Allium/efeitos dos fármacos , Animais , Bactérias/efeitos dos fármacos , Cadeia Alimentar , Nematoides , Oligoquetos/efeitos dos fármacos , Extratos Vegetais/toxicidade , RNA Ribossômico 16S/genética , Solo/química , Microbiologia do Solo
14.
Food Chem Toxicol ; 130: 142-153, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31112705

RESUMO

In this study five types of herbal teas were used to quantify the effect of comminution of the leaves on resulting PA exposure. Results show that PA levels extracted from intact leaves were consistently lower than from comminuted tea leaves. The Margin of Exposure (MOE) approach was applied to evaluate the consequences of this difference for the associated risks in the scenario of lifetime exposure. Furthermore, we considered medicinal use of these teas for shorter-than-lifetime exposure scenarios, and also analysed the risks of shorter-than-lifetime use of eight herbal medicines and 19 previously analysed plant food supplements. This analysis revealed that shorter-than-lifetime use resulted in MOE values < 10,000 upon use for 40-3450 weeks during a lifetime, with for only a limited number of herbal teas and medicines use of two weeks a year (150 weeks during a 75 year lifetime) would still raise a concern. It is concluded that taking more realistic conditions into account markedly reduces the concerns raised for these herbal preparations. These results also illustrate the need for development of a generally accepted method for taking short term exposure into account in risk assessment of compounds that are genotoxic and carcinogenic.


Assuntos
Preparações de Plantas/química , Preparações de Plantas/toxicidade , Alcaloides de Pirrolizidina/toxicidade , Chás de Ervas/análise , Chás de Ervas/toxicidade , Carcinógenos , Humanos , Modelos Biológicos , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Folhas de Planta/química , Plantas Medicinais/química , Alcaloides de Pirrolizidina/química , Fatores de Risco
15.
Fa Yi Xue Za Zhi ; 35(2): 224-229, 2019 Apr.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-31135119

RESUMO

Abstract: Objective To compare the differences of cardiotoxicity of alcohol extract from root, stem and leaf of Chloranthus serratus in the rats, and discuss preliminarily its mechanism of toxicity. Methods Rats were randomly divided into four groups: blank, root alcohol, stem alcohol and leaf alcohol, with 8 in each group. After 14 days of continuous intragastric administration, the body mass change curves were drawn. The cardiac coefficient was calculated. The contents of creatine kinase (CK), creatine kinase isoenzyme (CK-MB), lactate dehydrogenase (LDH) and α-hydroxybutyrate dehydrogenase (α-HBDH) as well as the content changes of oxidative stress indexes - total superoxide dismutase (T-SOD) and malondialdehyde (MDA) in the serum of rats were detected. The cardiac pathomorphology changes in the rats were observed. The expression of intercellular adhesion molecule (ICAM-1) and heme oxygenase (HO-1) in myocardial tissue was detected. Results Body mass growth rate: stem alcohol group was the smallest, followed by leaf alcohol group. The difference of cardiac coefficient of every group had no statistical significance (P>0.05). The myocardial tissues of stem alcohol group suffered the most serious damage, followed by the leaf alcohol group. The contents of CK, CK-MB, LDH and α-HBDH in stem alcohol group increased (P<0.05). The increase of MDA content and decrease of T-SOD content in stem alcohol group had statistical significance compared with the blank group and root alcohol group, while the leaf alcohol group only had statistical significance in the decrease of T-SOD content compared with the blank group (P<0.05). The positive expression of ICAM-1 enhanced and the expression of HO-1 protein decreased in every group after the intervention of different extracts. The change trend was stem alcohol > leaf alcohol > root alcohol group. Conclusion The alcohol extract from the stem has the highest cardiotoxicity, followed by the leaf extract, and its mechanism of toxicity may be related to oxidative stress.


Assuntos
Cardiotoxicidade , Coração/efeitos dos fármacos , Miocárdio/metabolismo , Estresse Oxidativo/fisiologia , Extratos Vegetais/toxicidade , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , Animais , Etanol , Malondialdeído , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
16.
BMC Vet Res ; 15(1): 178, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31142304

RESUMO

BACKGROUND: Avian infectious bronchitis (IB) is a disease that can result in huge economic losses in the poultry industry. The high level of mutations of the IB virus (IBV) leads to the emergence of new serotypes and genotypes, and limits the efficacy of routine prevention. Medicinal plants, or substances derived from them, are being tested as options in the prevention of infectious diseases such as IB in many countries. The objective of this study was to investigate extracts of 15 selected medicinal plants for anti-IBV activity. RESULTS: Extracts of S. montana, O. vulgare, M. piperita, M. officinalis, T. vulgaris, H. officinalis, S. officinalis and D. canadense showed anti-IBV activity prior to and during infection, while S. montana showed activity prior to and after infection. M. piperita, O. vulgare and T. vulgaris extracts had > 60 SI. In further studies no virus plaques (plaque reduction rate 100%) or cytopathogenic effect (decrease of TCID50 from 2.0 to 5.0 log10) were detected after IBV treatment with extracts of M. piperita, D. canadense and T. vulgaris at concentrations of extracts ≥0.25 cytotoxic concentration (CC50) (P < 0.05). Both PFU number and TCID50 increased after the use of M. piperita, D. canadense, T. vulgaris and M. officinalis extracts, the concentrations of which were 0.125 CC50 and 0.25 CC50 (P < 0.05). Real-time PCR detected IBV RNA after treatment with all plant extracts using concentrations of 1:2 CC50, 1:4 CC50 and 1:8 CC50. Delta cycle threshold (Ct) values decreased significantly comparing Ct values of 1:2 CC50 and 1:8 CC50 dilutions (P < 0.05). CONCLUSIONS: Many extracts of plants acted against IBV prior to and during infection, but the most effective were those of M. piperita, T. vulgaris and D. canadense .


Assuntos
Antivirais/farmacologia , Vírus da Bronquite Infecciosa/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais , Animais , Antivirais/toxicidade , Cercopithecus aethiops , Testes de Sensibilidade Microbiana , Extratos Vegetais/toxicidade , Reação em Cadeia da Polimerase em Tempo Real , Células Vero , Ensaio de Placa Viral
17.
Chin J Nat Med ; 17(4): 291-297, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31076132

RESUMO

Eight new annonaceous acetogenins, squamotin A-D (1-4), annosquatin IV-V (5 and 6), muricin O (7) and squamosten B (8), together with four known ones (9-12) were isolated from the seeds of Annona squamosa. Their structures were elucidated by chemical methods and spectral data. The inhibitory activities of compound 1-9 against three multidrug resistance cell lines were evaluated. All tested compounds showed strong cytotoxicity.


Assuntos
Acetogeninas/toxicidade , Annona/química , Sobrevivência Celular/efeitos dos fármacos , Sementes/química , Acetogeninas/química , Acetogeninas/isolamento & purificação , Acetogeninas/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/toxicidade , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade
18.
Regul Toxicol Pharmacol ; 105: 36-41, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30935955

RESUMO

Food-borne alkenylbenzenes are potential risks for human health because they are known to induce liver tumors in rodent bioassays at high dose levels. This carcinogenicity is ascribed to the conversion of their 1'-hydroxymetabolites to the ultimate DNA reactive and carcinogenic 1'-sulfoxymetabolites. The aim of this study was to investigate the in vitro genotoxicity of some botanical extracts used as Plant Food Supplements (PFS) and to compare it with the individual substances, estragole, safrole and their 1'-hydroxy-derivative activity. The genotoxicity of the PFSs was evaluated in HepG2 cell line by comet and micronucleus assays. Unlike the 1'-hydroxy derivatives, PFS extracts and parent alkenylbenzenes did not show genotoxicity at any of the tested concentrations. The sulfotransferase inhibitor pentachlorophenol (PCP) reduced the 1'-hydroxy compound-induced response in the comet and micronucleus assays, thus confirming that the formation of sulfoxy-metabolites is essential for inducing genotoxic effects. When the cells were treated with hydroxylated alkenylbenzenes in the presence of PFSs, a reduction in genotoxic activity of synthetic compounds was observed.


Assuntos
Anisóis/toxicidade , Derivados de Benzeno/toxicidade , Extratos Vegetais/toxicidade , Safrol/toxicidade , Derivados de Benzeno/química , Ensaio Cometa , Células Hep G2 , Humanos , Testes para Micronúcleos , Mutagênicos/toxicidade , Extratos Vegetais/química
19.
Regul Toxicol Pharmacol ; 105: 77-85, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30991075

RESUMO

Citrus sinensis contains glycoside hesperetin-7-rhamnoglucoside (hesperidin) which harbor an array of therapeutic potentials including antioxidant, anticancer, and anti-inflammatory. However, a systematic examination of safety is needed before its utilization. Hence, the present investigation is aimed to evaluate acute and sub-chronic toxicity of hesperidin isolated from the citrus fruit. Hesperidin (73%) was isolated from a methanolic extract of dried peel of the citrus fruit, characterized using FTIR, and standardized by HPLC. Its acute oral toxicity (AOT) and sub-chronic toxicity studies were carried out in Sprague-Dawley rats. Hesperidin (5000 mg/kg) showed 10% mortality in AOT. In sub-chronic toxicity study, hesperidin (250 and 500 mg/kg) did not induce any abnormalities in body weight, food consumption, clinical signs, ophthalmological and neurological observations, urine analysis, hematology, clinical chemistry, organ weights, and gross pathology. However, hesperidin (1000 mg/kg) showed significant (p < 0.05) alterations in body and organ weights, hematology, clinical chemistry, and tissue histopathology. To conclude, hesperidin has median lethal dose (LD50) of 4837.5 mg/kg, and Low Observed Adverse Effect Level (LOAEL) at 1000 mg/kg for both male and female Sprague-Dawley rats. Thus, hesperidin isolated from citrus fruit showed a good safety profile in animal study.


Assuntos
Antioxidantes/toxicidade , Citrus sinensis/química , Hesperidina/toxicidade , Extratos Vegetais/toxicidade , Administração Oral , Animais , Antioxidantes/administração & dosagem , Antioxidantes/isolamento & purificação , Relação Dose-Resposta a Droga , Feminino , Hesperidina/administração & dosagem , Hesperidina/isolamento & purificação , Dose Letal Mediana , Masculino , Metanol/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Subcrônica/métodos
20.
Molecules ; 24(7)2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934947

RESUMO

In this work, we explore the current knowledge about the phytochemistry and in vitro and in vivo evaluations of the extracts and, where appropriate, the main active components characterized and isolated from the Allamanda cathartica. Of the 15 Allamanda species, most phytochemical, pharmacological, and toxicological studies have focused on A. cathartica. These plants are used for the treatment of various health disorders. Numerous phytochemical investigations of plants from the A. cathartica have shown the presence of hydrocarbons, alcohols, esters, ethers, aldehydes, ketones, fatty acids, phospholipids, volatile compounds, phenolic compounds, flavonoids, alkaloids, steroids, terpenes, lactones, and carbohydrates. Various studies have confirmed that extracts and active substances isolated from the A. cathartica have multiple pharmacological activities. The species A. cathartica has emerged as a source of traditional medicine used for human health. Further studies on the phytochemical, pharmacological, and toxicological properties and their mechanisms of action, safety, and efficacy in the species of A. cathartica is recommended.


Assuntos
Apocynaceae/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Biotecnologia/métodos , Etnofarmacologia/métodos , Medicina Tradicional , Estrutura Molecular , Compostos Fitoquímicos/toxicidade , Extratos Vegetais/toxicidade , Plantas Medicinais/química , Toxicologia/métodos
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