RESUMEN
Rhipicephalus microplus (Ixodidae, canestrini, 1888) is an invasive ectoparasite of cattle which causes high economic losses in emerging countries such as Brazil. Phytochemical compounds have been tested as an alternative to synthetic acaricides due to potentially lower mammalian toxicity. This study evaluated the acaricidal activity against R. microplus of the 2-methoxy-clovan-9-ol rich fraction obtained from Eugenia copacabanensis Kiaersk.leaves, a little known Myrtaceae species from the Brazilian Atlantic Forest. This fraction was obtained by maceration with methanol, partition with n-hexane and purification by normal-phase column chromatography. GC-MS, 1H and 13C NMR and IR analysis contributed to the identification of a major compound as the sesquiterpene 2-methoxy-clovan-9-ol, reported for the first time for the Myrtaceae family. The fraction was tested against R. microplus unfed larvae and engorged females and a 93% larval mortality was observed at the concentration of 50 mg mL-1. Lower concentrations of the solution tested demonstrated a significant difference in egg mass weight, hatching and control percentage. Experiments with 50.0 mg mL-1 showed significative results, with lower concentration and maximum efficacy for both assays. The IC50 values for unfed larvae and engorged females were 21.76 and 11.13 mg mL-1, respectively. These results were similar to those obtained in other studies with isolated botanical compounds and essential oils. The lower IC50 for engorged females than for unfed R. microplus larvae had also been described for other plant materials, including plants from the same Myrtaceae family. The present result suggested different mechanisms of action of the compound on the reproductive biology of engorged females, improving its effect against egg viability. These results are important for tick control, suggesting that 2-methoxy-clovan-9-ol could be a potential natural acaricidal product against both R. microplus unfed larvae and engorged females.
Asunto(s)
Acaricidas , Eugenia , Ixodidae , Myrtaceae , Rhipicephalus , Femenino , Animales , Bovinos , Acaricidas/farmacología , Larva , Extractos Vegetales/farmacología , MamíferosRESUMEN
Leaves of Croton argyrophyllus contain essential oil with promising active components for the development of drugs and botanical insecticides. In this study, we evaluated the enzymatic pretreatment process to increase the extraction of essential oil from fresh and dried leaves of C. argyrophyllus. Pretreatment was carried out using a crude multienzymatic extract obtained via solid-state fermentation of forage palm by Aspergillus niger, and the extraction was performed by hydrodistillation. A Doehlert matrix was used to optimize the enzymatic pretreatment variables temperature and enzymatic extract. The effect of pretreatment time was also investigated. At optimum experimental conditions, 41.34°C, 140 min, and 130.73 mL of enzyme in 369.27 mL of water, the essential oil yield from fresh leaves subjected to enzymatic pretreatment increased by 9.35% and that from dry leaves by 6.77%. Based on chromatographic analysis (GC-MS), no compound was degraded in the extraction process. Micromorphological analysis confirmed the rupture of the glandular trichomes, favoring essential oil release. Therefore, enzymatic pretreatment associated with hydrodistillation increased the essential oil yield and is a promising application to obtain essential oil for therapeutic purposes without altering its composition.
Asunto(s)
Croton , Aceites Volátiles , Aceites Volátiles/análisis , Aceites Volátiles/química , Aceites Volátiles/farmacología , Croton/química , Aspergillus niger , Hojas de la Planta/química , Extractos Vegetales/químicaRESUMEN
Trypanosoma cruzi is the causative agent of Chagas disease which affects 8 million people in Latin America. The parasite possesses high capacity to evade host immune system and the available drugs to treat Chagas disease present low efficacy combined to serious side effects to patients. Therefore, the identification of alternative therapeutics is essential. Brazilian flora exhibits an immense diversity of metabolites with great potential to be developed into new drugs. We investigated the action of 2â³,3â³-dihydroochnaflavone a biflavonoid extracted from Luxemburgia nobilis Eichler ex Engl. (Ochnaceae) against T. cruzi (Y strain). Our experiments showed that this compound is effective against parasite epimastigote forms, presenting IC50 value of (2.5 ± 0.1) µM after 96 h of treatment. Ultrastructure alterations were also detected in treated epimastigotes especially mitochondrial enlargement at the kinetoplast region. At the concentration of 30 µM, the compound killed (61.6 ± 3.37)% of the parasite in its amastigote form. In addition, at the same concentration, the compound killed all trypamastigotes growing within murine macrophages after 7-9 days of infection. Nonetheless, the biflavonoid concentrations were harmless to murine enriched population of lymphocytes and peritoneal macrophages. These results indicate that 2â³,3â³- dihydroochnaflavone presents activity against T. cruzi.
Asunto(s)
Biflavonoides/farmacología , Ochnaceae/química , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Linfocitos/efectos de los fármacos , Macrófagos Peritoneales/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Extractos Vegetales/química , Extractos Vegetales/farmacología , Pruebas de ToxicidadRESUMEN
In this study, sacha inchi oil (SIO) (Plukenetia volubilis L.) was microencapsulated via complex coacervation of ovalbumin (OVA) and sodium alginate (AL), and the microcapsule properties were characterized. The omega-3 content in the SIO was evaluated after in vitro gastric simulation and microencapsulation. The coacervate complex between OVA and AL was evaluated based on electrostatic interactions and developed for use as a wall material via the SIO microencapsulation process. The best mass ratio for the biopolymers (OVA:AL) was 4:1 at pH 3.8, and the complex exhibited a thermal resistance at 189.86⯰C. The SIO microcapsules showed a high encapsulation efficiency of approximately 94.12% in the ratio (OVA:AL) of 1:1. Furthermore, microencapsulated SIO presented resistance under gastric conditions with a low release of acyl (ω-3) units. These results demonstrate that it is possible to use OVA:AL as encapsulating agents to protect bioactive compounds and to improve the thermal behavior of microcapsules.
Asunto(s)
Composición de Medicamentos/métodos , Euphorbiaceae/metabolismo , Aceites de Plantas/química , Alginatos/química , Rastreo Diferencial de Calorimetría , Cápsulas/química , Euphorbiaceae/química , Ácidos Grasos Omega-3/química , Concentración de Iones de Hidrógeno , Ovalbúmina/química , Electricidad EstáticaRESUMEN
Medicinal plants with antimicrobial action have been investigated for uses against biofilms, among which, Cymbopogon nardus, citronella, stands out as a promising species. The present study aims to evaluate the antimicrobial and antibiofilm action of the essential oil of C. nardus (EOCN) and geraniol on Gram-negative and positive bacteria from the determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration and inhibition of biofilms. In the results, the EOCN produced a 41 mm halo on S. aureus, which was susceptible with MIC values of 0.5 and 0.25 mg/mL for the EOCN and geraniol respectively, both with bactericidal effect. The antibiofilm action was confirmed, the EOCN and geraniol reduced the biofilm biomass of S. aureus up to 100% between 0.5 and 4 mg/mL concentrations. The reduction of cell viability was 0.25 and 1 mg/mL, of EOCN and geraniol, respectively. EOCN and geraniol were shown to be promising antibiotic against S. aureus.
RESUMEN
A phytochemical study of leaves and twigs of Psychotria nuda resulted in 19 compounds, including five indole alkaloids, N,N,N-trimethyltryptamine, lyaloside, strictosamide, strictosidine, and 5α-carboxystrictosidine; two flavonolignans, cinchonain Ia and cinchonain Ib; an iridoid, roseoside; a sugar, lawsofructose; a coumarin, scopoletin; a diterpene, phytol; three triterpenes, pomolic acid, spinosic acid, and rotungenic acid; and five steroids, sitosterol, stigmasterol, campesterol, ß-sitosterol-3-O-ß-d-glucoside, and ß-stigmasterol-3-O-ß-d-glucoside. Some compounds were evaluated for their in vitro activity against Mycobacterium tuberculosis and their ability to inhibit NO production by macrophages stimulated by lipopolysaccharide (LPS). The compounds pomolic acid, spinosic acid, strictosidine, and 5α-carboxystrictosidine displayed antimycobacterial activity with minimum inhibitory concentrations ranging from 7.1 to 19.2 µg/mL. These compounds showed promising inhibitory activity against NO production (IC50 3.22 to 25.5 µg/mL). 5α-carboxystrictosidine did not show cytotoxicity against macrophages RAW264.7 up to a concentration of 100 µg/mL. With the exception of strictosamide, this is the first report of the occurrence of these substances in P. nuda.
Asunto(s)
Alcaloides/análisis , Antibacterianos/análisis , Antioxidantes/análisis , Psychotria/química , Triterpenos/análisis , Alcaloides/farmacología , Animales , Antibacterianos/farmacología , Antioxidantes/farmacología , Lipopolisacáridos/efectos adversos , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Espectroscopía de Resonancia Magnética , Ratones , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Mycobacterium tuberculosis/efectos de los fármacos , Óxido Nítrico/metabolismo , Extractos Vegetales/química , Hojas de la Planta/química , Células RAW 264.7 , Triterpenos/farmacologíaRESUMEN
Twenty compounds were isolated from the hydroethanolic extract of the stems of Siolmatra brasiliensis, five flavonoids, two lignans, one glucosyl phytosterol, seven nor-cucurbitacins, one new phenolic derivative named siolmatrin (1) and four new dammarane-type saponins named siolmatrosides II-V (2-5), the structures of the compounds were assigned by means of 1D and 2D NMR experiments and HRESIMS of the natural compounds and some acetyl derivatives. The effects of the crude hydroethanolic extract (SbExt) and the ethyl acetate fraction (SbEtAc) of Siolmatra brasiliensis stems on the formation of advanced glycation end-products (AGEs) were also investigated. In the in vitro model system of protein glycation using bovine serum albumin (BSA) and glucose, addition of SbExt or SbEtAc inhibited the formation of fluorescent AGEs, in parallel to minor levels of fructosamine (SbEtAc) and markers of tyrosine and tryptophan oxidation (SbExt and SbEtAc). Protein crosslinking, which represents changes of late stages of protein glycation, was reduced in the presence of SbExt and SbEtAc. Siolmatra brasiliensis stems seem to be a promising source of compounds having ability to prevent glycoxidation changes, arising as an interesting option to be studied as a complementary therapy for complications of diabetes.
Asunto(s)
Cucurbitaceae/química , Flavonoides/farmacología , Fenoles/farmacología , Fitosteroles/farmacología , Saponinas/farmacología , Flavonoides/aislamiento & purificación , Productos Finales de Glicación Avanzada/metabolismo , Glicosilación , Estructura Molecular , Oxidación-Reducción , Fenoles/aislamiento & purificación , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Fitosteroles/aislamiento & purificación , Extractos Vegetales/química , Tallos de la Planta/química , Saponinas/aislamiento & purificaciónRESUMEN
The study aimed to evaluate in vitro antioxidant, anticholinesterase and antidiabetic properties of Ouratea hexasperma (A. St.-Hil.) Baill. The inflorescence methanol extract and the ethyl acetate fraction of leaves and stems reported the highest Relative Antioxidant Capacity Index (RACI), whereas the dichloromethane fraction of leaves was the best inhibitor of α-amylase and α-glucosidase. Trans-3-O-methyl-resveratrol-2-C-ß-glucoside, lithospermoside, 2,5-dimethoxy-p-benzoquinone, lup-20(30)-ene-3ß,28-diol, 7-O-methylgenistein, apigenin and luteolin and amentoflavone were isolated from O. hexasperma. Resveratrol derivative was isolated for the first time in Ochnaceae family. Luteolin, followed by apigenin, reported the highest Relative Antioxidant Capacity Index and they were also the best inhibitors of α-glucosidase enzyme.
Asunto(s)
Antioxidantes/farmacología , Inhibidores de la Colinesterasa/farmacología , Hipoglucemiantes/farmacología , Ochnaceae/química , Antioxidantes/química , Apigenina/aislamiento & purificación , Apigenina/farmacología , Inhibidores de la Colinesterasa/química , Evaluación Preclínica de Medicamentos/métodos , Inhibidores de Glicósido Hidrolasas/farmacología , Hipoglucemiantes/química , Luteolina/aislamiento & purificación , Luteolina/farmacología , Metanol/química , Extractos Vegetales/química , Hojas de la Planta/química , alfa-Amilasas/antagonistas & inhibidoresRESUMEN
The aim of this work was to studied the formation, stability and characterization of oil-in-water emulsions formed by Sacha Inchi oil (SIO) 8% (w/w) with either ovalbumin (Ova) or Tween 80 (Tw80), as emulsifiers at 0.5%-2.0% (w/w) and stabilized with pectin (Pec) at 1.0%-3.0% (w/w) or xanthan gum (XG) at 0.25%-1.0% (w/w). The emulsions were evaluated at 0, 1, 7 and 14â¯days after preparation and kept at a temperature of 25⯱â¯1⯰C for the ζ-potential, particle size distribution, polydispersion, and emulsion stability index measurements. The emulsions were characterized by optical microscopy, viscosity and rheological behavior. It was observed that it is possible to form oil-in-water emulsions with SIO-Ova and Pec that are stable at 25⯰C for at least 14â¯days with a polydispersion value between 0.2 and 0.5. However, the emulsions with SIO-Ova and XG are stable at several concentrations of XG but are more viscous and can form aggregates. The presence of a biopolymer is essential for the kinetic stability of the emulsions containing Ova as the emulsifier. For the emulsions containing Tw80, this conclusion applies only to emulsions with XG concentrations of 0.5% to 1.0%, in which the stability mechanism is distinct.
Asunto(s)
Emulsiones/química , Pectinas/química , Polisacáridos Bacterianos/química , Reología , Aceites/química , Ovalbúmina/química , Polisorbatos/química , Viscosidad , Agua/químicaRESUMEN
This study evaluated the acaricidal activity of the methanol extract of Acmella oleracea with 0.187% of spilanthol against immature stages of Amblyomma sculptum. The packet test was used to evaluate the extract's activity on unengorged larvae and nymphs, testing concentrations of 0.4 to 50â¯mg/mL for larvae and 12.5 to 200.0â¯mg/mL for nymphs. For the engorged stages, the immersion test was used, at concentrations of 0.4 to 50â¯mg/mL for larvae and 12.5 to 200.0â¯mg/mL for nymphs. The methanol extract caused 100% mortality of the unengorged larvae and nymphs starting at concentrations of 12.5 and 200.0â¯mg/mL, respectively. For engorged larvae and nymphs, the mortality was 100% starting from concentrations of 12.5 and 150.0â¯mg/mL, respectively. The LC50 for unengorged larvae was 3.2â¯mg/mL, while for engorged larvae it was 6.6â¯mg/mL. For unengorged nymphs, the LC50 was 38.5â¯mg/mL, but it was not possible to calculate the corresponding value for engorged nymphs because the data did not fit the probit model. These results demonstrate that the methanol extract of A. oleracea has acaricidal activity against different immature stages of A. sculptum.
Asunto(s)
Acaricidas , Asteraceae/química , Ixodidae , Extractos Vegetales , Alcamidas Poliinsaturadas , Animales , Ixodidae/crecimiento & desarrollo , Larva/crecimiento & desarrollo , Ninfa/crecimiento & desarrolloRESUMEN
BACKGROUND: The emergence of multidrug-resistant bacteria is a worldwide concern and in order to find an alternative to this problem, the occurrence of antimicrobial compounds in Plectranthus amboinicus essential oil was investigated. Thus, this study aims to determine susceptibility of Staphylococcus aureus isolated from food to antibiotics, P. amboinicus essential oil (PAEO) and carvacrol. METHODS: Leaves and stem of P. amboinicus were used for extraction of essential oil (PAEO) by hydrodistillation technique and EO chemical analysis was performed by gas chromatography coupled to a mass spectrometer. S. aureus strains (n = 35) isolated from food and S. aureus ATCC 6538 were used to evaluate the antimicrobial and antibiofilm activity of PAEO and carvacrol. All strains (n = 35) were submitted to antimicrobial susceptibility profile by disk diffusion method. Determination of MIC and MBC was performed by microdilution technique and antibiofilm activity was determined by microtiter-plate technique with crystal violet assay and counting viable cells in Colony Forming Units (CFU). RESULTS: Carvacrol (88.17%) was the major component in the PAEO. Antibiotic resistance was detected in 28 S. aureus strains (80%) and 12 strains (34.3%) were oxacillin and vancomycin-resistant (OVRSA). From the 28 resistant strains, 7 (25%) showed resistance plasmid of 12,000 bp. All strains (n = 35) were sensitive to PAEO and carvacrol, with inhibition zones ranging from 16 to 38 mm and 23 to 42 mm, respectively. The lowest MIC (0.25 mg mL-1) and MBC (0.5 mg mL-1) values were observed when carvacrol was used against OVRSA. When a 0.5 mg mL-1 concentration of PAEO and carvacrol was used, no viable cells were found on S. aureus biofilm. CONCLUSION: The antibacterial effect of carvacrol and PAEO proves to be a possible alternative against planktonic forms and staphylococcal biofilm.
Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Farmacorresistencia Bacteriana , Monoterpenos/farmacología , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Plectranthus/química , Staphylococcus aureus/efectos de los fármacos , Cimenos , Humanos , Oxacilina/farmacología , Hojas de la Planta/química , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/fisiología , Vancomicina/farmacologíaRESUMEN
In this study, sacha inchi oil (SIO) was microencapsulated by emulsion-based systems using ovalbumin (Ova), pectin (Pec), and xanthan gum (XG), followed by freeze-drying. The microencapsulation was confirmed using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The stability of omega-3 in SIO alone as well as in microencapsulated SIO was assessed by nuclear magnetic resonance (1H NMR) spectroscopy after human gastric simulation (HGS). The SEM results revealed distinct structures for the two types of microcapsules. The thermograms showed that the thermal resistance was increased in the microencapsulated SIO, indicating that the emulsion-based system may be a way to protect the omega-3 in the SIO. In addition, the microencapsulation conferred an increased crystallinity degree, indicating a higher structural organization. Moreover, this method did not affect the stability of SIO, as confirmed by 1H NMR. The release of omega-3 acyl units from the SIO was correlated with the decrease of the methynic proton (sn, 2 position) of triacylglycerol (TAG). In contrast, the increase of 1,3-diglycerides was negatively correlated with the decrease of glyceryl groups (sn, 1,3 positions). The HGS conditions did not significantly alter the stability of the omega-3 of SIO over 180min. The SIO-Ova microcapsules had a similar behavior to the SIO, and the presence of Ova was not enough to prevent the decrease of omega-3 content over 180min. The SIO-Ova-Pec and SIO-Ova-XG microcapsules were shown to protect the omega-3 content effectively. In conclusion, the microcapsules developed in this study can be used to transport nutraceutical compounds because they are resistant to the human gastric conditions tested in vitro.
Asunto(s)
Portadores de Fármacos/química , Composición de Medicamentos/métodos , Aceites de Plantas/química , Cápsulas , Suplementos Dietéticos , Emulsiones , Ácidos Grasos Omega-3/química , Liofilización , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Difracción de Rayos XRESUMEN
OBJECTIVE: Annona tomentosa R.E.Fr is a species not endemic to Brazil that belongs to the phytogeographic areas of the Amazon, Cerrado and Pantanal. Popularly known as "araticum rasteiro" or "araticum de moita", A. tomentosa is edible and tea made from the leaves has been used as an anti-inflammatory by native communities. There is no scientific evidence for these uses of A. tomentosa, especially those related to the control of pain and inflammation. For this reason, in the present study we evaluated the antinociceptive and anti-inflammatory activities of partitions from the methanolic extract of A. tomentosa leaves (A. tomentosa leaf methanolic extract (ATFM) in hexane partition: ATFM-H; ATFM in dichloromethane partition: ATFM-D; ATFM in ethyl acetate partition: ATFM-Ac; ATFM in butanol partition: ATFM-B) in mice. METHODS: The antinociceptive effects of leaf extracts from A. tomentosa were evaluated by abdominal writhing and tail-flick tests, while the anti-inflammatory effects were evaluated by paw oedema and air-pouch tests. The locomotor activity was evaluated with the open-field test. Furthermore, we evaluated the possible action mechanism of A. tomentosa, using naloxone, nitro-L-arginine methyl ester, glibenclamide, atropine, naltrindole and norbinaltorphimine in tail-flick tests. The productions of tumor necrosis factor α (TNF-α) and interleukin (IL)-1ß were also evaluated. RESULTS: The chromatographic fractionation of the partitions of the methanolic extract from the leaves of A. tomentosa revealed the presence of diterpenes, flavonoids, and steroids compounds. From the analysis of the hexane partition kaurenoic acid was identified as the major component. ATFM-H and ATFM-D had a significant antinociceptive effect in acute pain models in mice. The ATFM-H showed central antinociceptive effect from the involvement of the δ opioid receptors, without causing alterations in the locomotor activity of the mice, while ATFM-D was effective in decreasing paw oedema and TNF-α and IL-1ß production. CONCLUSION: These results demonstrate that leaf extracts from A. tomentosa present antinociceptive and anti-inflammatory effects that can to be used in relieving algesic and inflammatory conditions.
Asunto(s)
Analgésicos/farmacología , Annona , Antiinflamatorios/farmacología , Extractos Vegetales/farmacología , Animales , Annona/química , Masculino , Ratones , Hojas de la Planta/químicaRESUMEN
We evaluated the acaricidal activity of Acmella oleracea methanol extract and spilanthol on Rhipicephalus microplus and Dermacentor nitens. The extract was made through maceration with methanol. From this extract, a dichloromethane fraction with 99% spilanthol was obtained and tested on R. microplus larvae and engorged females and D. nitens larvae. For evaluation against larvae, the modified larval packet test was used, and both the methanol extract and dichloromethane fraction were tested at concentrations of 0.2-50mg/mL. The modified larval packet test was also used in the lethal time (LT) test, with the methanol extract at a concentration of 12.5mg/mL and the percentage mortality was assessed after 15, 30, 45, 60, 75, 90, 120min and 24h. The 50% lethal time calculation (LT50) was performed in this test. The engorged female test was performed with R. microplus only, at concentrations of 25-200mg/mL for methanol extract and 2.5-20.0mg/mL for spilanthol. The methanol extract caused 100% mortality of the R. microplus and D. nitens larvae at concentrations of 3.1 and 12.5mg/mL, respectively. Spilanthol resulted in 100% mortality of R. microplus larvae at concentration of 1.6mg/mL and of D. nitens at 12.5mg/mL. In the lethal time assay using the methanol extract, the mortality rate was 100% for R. microplus and D. nitens larvae after 120min and 24h, with LT50 values of 38 and 57min, respectively. In the test of females, the egg mass weight and the hatching percentage of the groups treated with concentrations equal to or higher than 50.0mg/mL of methanol extract were significantly reduced (p<0.05), while for spilanthol, the reduction of the egg mass weight and hatching percentage occurred from concentrations of 10.0mg/mL and 2.5mg/mL, respectively. Females treated with 200.0mg/mL of extract died before starting oviposition, resulting in 100% effectiveness, while the best efficacy for spilanthol was 92.9% at a concentration of 20.0mg/mL. Thus we conclude that the methanol extract of A. oleracea and spilanthol have acaricidal activity against R. microplus and D. nitens.
Asunto(s)
Acaricidas/farmacología , Amidas/farmacología , Asteraceae/química , Enfermedades de los Bovinos/tratamiento farmacológico , Dermacentor/efectos de los fármacos , Extractos Vegetales/farmacología , Rhipicephalus/efectos de los fármacos , Infestaciones por Garrapatas/veterinaria , Acaricidas/química , Acaricidas/aislamiento & purificación , Amidas/química , Amidas/aislamiento & purificación , Animales , Brasil , Bovinos , Enfermedades de los Bovinos/parasitología , Femenino , Flores/química , Larva/efectos de los fármacos , Metanol , Oviposición/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Tallos de la Planta/química , Alcamidas Poliinsaturadas , Infestaciones por Garrapatas/tratamiento farmacológico , Infestaciones por Garrapatas/parasitologíaRESUMEN
For control of Aedes aegypti, the main vector of dengue, botanical insecticides can be a viable alternative. Herein, we evaluated the chemical composition and insecticidal activity of the essential oils of the leaves of Croton tetradenius on Ae. aegypti larvae and adults. We also evaluated the acute toxicity in Mus musculus. The essential oil chemical analysis was performed using chromatography coupled with mass spectrometry and flame ionization detection. Female mice were used for assessing toxicity according to the Organization for Economic Cooperation and Development's Test Guideline 423/2001. Doses administered to mice orally and intraperitoneally were 5, 50, 300, and 2000 mg kg(-1). There was a greater toxic effect on larvae (LC50 = 0.152 mg mL(-1) and LC90 = 0.297 mg mL(-1)) and on adults (LC50 = 1.842 mg mL(-1) and LC90 = 3.156 mg mL(-1)) of Ae. aegypti after 24 h of exposure, when compared to other periods of exposure. Chemical analysis revealed 26 components, with camphor (25.49 %) as the major component. The acute toxicity via the intraperitoneal route identified an LD50 = 200 mg kg(-1) and by the oral route an LD50 = 500 mg kg(-1). Thus, the essential oil of C. tetradenius presents insecticidal potential for Ae. aegypti and has high safety threshold at the concentrations evaluated in this study.
Asunto(s)
Aedes/efectos de los fármacos , Croton/química , Insecticidas/toxicidad , Aceites Volátiles/toxicidad , Extractos Vegetales/toxicidad , Aedes/crecimiento & desarrollo , Animales , Femenino , Insecticidas/aislamiento & purificación , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Ratones , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/químicaRESUMEN
This study aimed at assessing the combined effect of thymol, carvacrol and (E)-cinnamaldehyde on Amblyomma sculptum and Dermacentor nitens larvae. The effects resulting from treatments were evaluated by means of the modified larval packet test. In order to determine the LC50, components of essential oils, the monoterpenes thymol, carvacrol and phenylpropanoid (E)-cinnamaldehyde were individually tested at different concentrations. After determining the LC50, each essential oil component was separately evaluated and then combined with another substance at a 1:1 proportion at the LC50 concentration and at 1/2 and 1/4 of the LC50. For A. sculptum, the lowest LC50 value was obtained for (E)-cinnamaldehyde (1.40 mg/ml), followed by thymol (2.04 mg/ml) and carvacrol (3.49 mg/ml). The same order of effectiveness was observed for D. nitens, with values of 1.68, 2.17 and 3.33 mg/ml, respectively. In the evaluation of component associations of essential oils against A. sculptum larvae, only the combinations between carvacrol and thymol (LC50) and carvacrol and (E)-cinnamaldehyde (1/4 LC50) presented a moderate synergetic effect. In turn, for D. nitens larvae, the combinations between thymol and carvacrol (LC50 and 1/2 LC50) presented a synergetic effect, while the others presented an additive or antagonistic effect. Therefore, it can be concluded that the combination of thymol and carvacrol (LC50) has a moderate synergetic effect against A. sculptum larvae, while thymol, combined with carvacrol (LC50 and 1/2 LC50), has a synergetic effect against D. nitens larvae.
Asunto(s)
Acroleína/análogos & derivados , Ixodidae/efectos de los fármacos , Monoterpenos/farmacología , Timol/farmacología , Acroleína/administración & dosificación , Acroleína/química , Acroleína/farmacología , Animales , Cimenos , Quimioterapia Combinada , Larva/efectos de los fármacos , Monoterpenos/administración & dosificación , Monoterpenos/química , Aceites Volátiles/administración & dosificación , Aceites Volátiles/química , Aceites Volátiles/farmacología , Aceites de Plantas/administración & dosificación , Aceites de Plantas/química , Aceites de Plantas/farmacología , Timol/administración & dosificación , Timol/químicaRESUMEN
Lophanthera lactescens is a medicinal plant commonly used in traditional medicine to relieve fever and pain in inflammatory processes. In the present study, the in vivo antinociceptive and anti-inflammatory effects of the methanolic extract from L. lactescens have been investigated. Antinociceptive activity was evaluated through writhing, formalin, and tail flick tests, while the anti-inflammatory activity was evaluated through paw oedema and air pouch tests in mice. A phytochemical analysis was performed. The extract produced significant inhibition on nociception induced by acetic acid-induced abdominal writhing, formalin, and tail flick tests, and on inflammation induced by oedema and air pouch tests. The previous administration of atropine and glibenclamide reduced the antinociceptive effect produced by the methanolic extract from L. lactescens on the tail flick test in 89% and 66%, respectively. The methanolic extract had no significant effect in the open field test. No intoxication symptoms were observed in the animals administered orally at increasing doses up to 2000 mg/kg. The methanolic extract from the stem bark of L. lactescens possesses antinociceptive properties on models of acute pain induced by chemical and thermal stimuli as well as in models of inflammation and further suggests that this anti-inflammatory activity might involve inhibition of the proinflammatory cytokines, and the antinociceptive activity might involve participation of the cholinergic system and adenosine triphosphate-dependent K+ channel.
Asunto(s)
Analgésicos/aislamiento & purificación , Antiinflamatorios/aislamiento & purificación , Malpighiaceae/química , Extractos Vegetales/farmacología , Plantas Medicinales/química , Analgésicos/farmacología , Animales , Antiinflamatorios/farmacología , Brasil , Masculino , Metanol , Ratones , Estructura Molecular , Corteza de la Planta/química , Tallos de la Planta/químicaRESUMEN
Clusia nemorosa has been widely used in folk medicine to treat various ailments, including headaches and inflammation. Investigation of the fruits of Clusia nemorosa (Clusiaceae) led to the isolation and characterization of a new phloroglucinol derivative, named 6S,8S,28S-nemorosic acid (1), together with seven known compounds: friedelin (2), ß-sitosterol (3), stigmasterol (4), ß-sitosterol glycoside (5), kaempferol (6), quercetin (7) and dimethyl citrate (8). The structures were determined by extensive 1D- and 2D-NMR, CD and MS spectroscopic analyses.
Asunto(s)
Clusiaceae/química , Floroglucinol/química , Flavonoides/química , Flavonoides/aislamiento & purificación , Frutas/química , Imagen por Resonancia Magnética , Medicina Tradicional , Resonancia Magnética Nuclear Biomolecular , Floroglucinol/aislamiento & purificaciónRESUMEN
This study aimed at the characterization of blends of Sacha Inchi oil (SIO) with different ratios of SO (soybean oil) and CO (corn oil) by nuclear magnetic resonance ((1)H NMR), compared with the data obtained by gas chromatography with a flame ionization detector (GC-FID). The (1)H NMR and GC-FID data from different ratios of SIO were adjusted by a second order polynomial equation. The two techniques were highly correlated (R(2) values ranged from 0.995 to 0.999), revealing that (1)H NMR is an efficient methodology for the quantification of omega-3 fatty acids in oils rich in omega-6 fatty acids or vice versa such as SO and CO and, on the other hand, can be used to quantify ω-6 in oils rich in ω-3, such as SIO.
Asunto(s)
Cromatografía de Gases/métodos , Euphorbiaceae/química , Ácidos Grasos/química , Aceites de Plantas/química , Espectroscopía de Protones por Resonancia Magnética/métodos , Aceite de Maíz/química , Semillas/química , Aceite de Soja/químicaRESUMEN
The leaves of Myrcia ovata, popularly known as "laranjinha do mato", are frequently used as an infusion in folk medicine. The essential oil obtained from these leaves is rich in citral, a mixture of neral and geranial isomers, known for its analgesic effect. Male Swiss mice (20-22 g) were tested in models of acute pain (acetic acid-induced abdominal writhing, tail flick, and formalin tests) and acute inflammation (paw oedema and air pouch tests) as well as in a model for evaluation of spontaneous motor performance (open-field test). The essential oil from M. ovata was administered orally at doses of 50-300 mg/kg. In addition, water, vehicle, morphine (5.01 mg/kg for evaluation of pain and motor performance), acetyl salicylic acid (200 mg/kg in the formalin test), and dexamethasone (2.25 mg/kg for evaluation of oedema formation, leukocyte extravasation, and quantification of cytokines) were administered. The essential oil showed a significant effect at doses of 200 and 300 mg/kg in the acute pain and acute inflammation tests. The effect of the essential oil was reduced by pretreatment with naloxone. The essential oil did not induce motor impairment. The extract was not toxic after oral administration (LD50 > 3000 mg/kg). These data provide initial evidence that the traditional use of M. ovata can be effective in reducing pain and inflammation.