RESUMEN
The chemical composition and antibacterial activity of essential oils from 10 commonly consumed herbs: Citrus aurantium, C. limon, Lavandula angustifolia, Matricaria chamomilla, Mentha piperita, M. spicata, Ocimum basilicum, Origanum vulgare, Thymus vulgaris and Salvia officinalis have been determined. The antibacterial activity of these oils and their main components; i.e. camphor, carvacrol, 1,8-cineole, linalool, linalyl acetate, limonene, menthol, a-pinene, b-pinene, and thymol were assayed against the human pathogenic bacteria Bacillus subtilis, Enterobacter cloacae, Escherichia coli O157:H7, Micrococcus flavus, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella enteritidis, S. epidermidis, S. typhimurium, and Staphylococcus aureus. The highest and broadest activity was shown by O. vulgare oil. Carvacrol had the highest antibacterial activity among the tested components.
Asunto(s)
Antibacterianos/farmacología , Aceites Volátiles/farmacología , Plantas Medicinales/química , Monoterpenos Acíclicos , Antibacterianos/química , Bacillus subtilis/efectos de los fármacos , Monoterpenos Bicíclicos , Compuestos Bicíclicos con Puentes/química , Compuestos Bicíclicos con Puentes/farmacología , Alcanfor/química , Alcanfor/farmacología , Citrus/química , Ciclohexanoles/química , Ciclohexanoles/farmacología , Ciclohexenos/química , Ciclohexenos/farmacología , Cimenos , Enterobacter cloacae/efectos de los fármacos , Escherichia/efectos de los fármacos , Eucaliptol , Lavandula/química , Limoneno , Matricaria/química , Mentha piperita/química , Mentha spicata/química , Mentol/química , Mentol/farmacología , Micrococcus luteus/efectos de los fármacos , Monoterpenos/química , Monoterpenos/farmacología , Aceites Volátiles/química , Origanum/química , Proteus mirabilis/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Salmonella enteritidis/efectos de los fármacos , Salvia officinalis/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos , Terpenos/química , Terpenos/farmacología , Timol/química , Timol/farmacología , Thymus (Planta)/químicaRESUMEN
The soybean phytoestrogen, genistein, is increasingly consumed as an alternative therapeutic for age-related diseases, namely cardiovascular conditions, cancer and osteoporosis. However, despite the beneficial effects on health, concern has been raised that this isoflavone also acts as an endocrine-disrupting chemical. The aim of this study was to examine the effects of genistein on immunohistomorphometric features of pituitary adrenocorticotropic cells (ACTH) and blood concentrations of ACTH and corticosterone in orchidectomized middle-aged male rats. Sixteen-month-old Wistar rats were divided into sham-operated (SO), orchidectomized (Orx) and genistein-treated orchidectomized (Orx+G) groups. Genistein (30mg/kg/day) was administered subcutaneously for three weeks, while the control groups received the vehicle alone. ACTH cells were identified by the peroxidase-antiperoxidase (PAP) immunohistochemical procedure. Circulating concentrations of ACTH and corticosterone were measured by immunoassay. Orchidectomy reduced (p<0.05) the cell volume and the relative volume of ACTH cells in comparison to SO rats. Genistein treatment further decreased (p<0.05) these morphometric parameters and reduced (p<0.05) circulating ACTH and corticosterone concentrations by more than 20% in comparison to both Orx and SO rats. In conclusión, genistein modulated the immunohistomorphometric features of ACTH cells and decreased blood ACTH and corticosterone levels, which supports evidence that this isoflavone affects the hypothalamic-pituitary-adrenal axis and suppresses glucocorticoid hormone secretion.
Asunto(s)
Hormona Adrenocorticotrópica/sangre , Andropausia , Corticosterona/sangre , Genisteína/farmacología , Adenohipófisis/efectos de los fármacos , Animales , Inmunoensayo , Inmunohistoquímica , Masculino , Modelos Animales , Orquiectomía , Adenohipófisis/citología , Adenohipófisis/metabolismo , Ratas , Ratas WistarRESUMEN
The potential antifungal effects of Thymus vulgaris L., Thymus tosevii L., Mentha spicata L., and Mentha piperita L. (Labiatae) essential oils and their components against 17 micromycetal food poisoning, plant, animal and human pathogens are presented. The essential oils were obtained by hydrodestillation of dried plant material. Their composition was determined by GC-MS. Identification of individual constituents was made by comparison with analytical standards, and by computer matching mass spectral data with those of the Wiley/NBS Library of Mass Spectra. MIC's and MFC's of the oils and their components were determined by dilution assays. Thymol (48.9%) and p-cymene (19.0%) were the main components of T. vulgaris, while carvacrol (12.8%), a-terpinyl acetate (12.3%), cis-myrtanol (11.2%) and thymol (10.4%) were dominant in T. tosevii. Both Thymus species showed very strong antifungal activities. In M. piperita oil menthol (37.4%), menthyl acetate (17.4%) and menthone (12.7%) were the main components, whereas those of M. spicata oil were carvone (69.5%) and menthone (21.9%). Mentha sp. showed strong antifungal activities, however lower than Thymus sp. The commercial fungicide, bifonazole, used as a control, had much lower antifungal activity than the oils and components investigated. It is concluded that essential oils of Thymus and Mentha species possess great antifungal potential and could be used as natural preservatives and fungicides.
Asunto(s)
Antifúngicos/química , Antifúngicos/farmacología , Mentha/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Thymus (Planta)/química , Animales , Hongos/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , HumanosRESUMEN
Ethanol solutions of essential oil of Ocimum basilicum and its main component, linalool (both isomer forms), all in three concentrations, as well as botanical standard Bioneem (0.5%), were tested for their toxicity and antifeedant activity against the second instar gypsy moth larvae in the laboratory bioassay. The essential oil of O. basilicum was subjected to gas chromatography analysis, and totally 37 compounds were detected, of which linalool was predominantly present. All tested solutions showed low to moderate larvicidal effect in both residual toxicity test and in chronic larval mortality bioassay. Chronic mortality tests showed that obtained mortality was a consequence of starving rather than ingestion of treated leaves. However, antifeedant index achieved by application of tested solutions in feeding choice assay was remarkable. Foliar application of all tested compounds deterred feeding by L2 in the same percent as Bioneem. Antifeedant index was relatively high at all tested treatments (85-94%); moreover, the larval desensitization to repelling volatiles has not occurred after five days of observation. Low toxic and high antifeedant properties make these plant-derived compounds suitable for incorporation in integrated pest management programs, especially in urban environments.
Asunto(s)
Control de Insectos/métodos , Insecticidas/toxicidad , Monoterpenos/toxicidad , Mariposas Nocturnas/efectos de los fármacos , Ocimum/toxicidad , Monoterpenos Acíclicos , Animales , Bioensayo , Cromatografía de Gases , Relación Dosis-Respuesta a Droga , Etanol/química , Isomerismo , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Limoninas/toxicidad , Mariposas Nocturnas/crecimiento & desarrollo , Estándares de Referencia , Solventes/químicaRESUMEN
Nutritional supplements containing soybean phytoestrogens, the isoflavones genistein (G) and daidzein (D), are increasingly used as alternative therapy for osteoporosis, cancer, and cardiovascular and other diseases with a frequency that increases with advancing age. In this study we examined the effects of subcutaneous administration of either G or D on serum lipid levels in orchidectomized (Orx) and intact (IA) middle-aged male rats, which are experimental models of andropause. Sixteen-month-old Wistar rats were treated with 10 mg/kg and 30 mg/kg of either G or D. The control groups received testosterone, estradiol, or vehicle for 3 weeks, after which the total serum cholesterol (TC), low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), and total triglycerides (TT) were measured. Compared with the matching vehicle-treated controls, the higher doses of G and D and testosterone treatment significantly (P < 0.05) lowered the TC and lipoprotein cholesterol levels. The greatest effect was observed regarding LDL-C in both Orx and IA males after G and D treatments, in which LDL-C decreased by more than 30%. The lower isoflavone doses induced a significant cholesterol-lowering effect (P < 0.05) only in the Orx group. Like the estradiol treatment, the higher doses of G and D increased the TT levels in both rat models by more than 50% (P < 0.05). The lower doses of isoflavones increased TT only in the Orx group. In male middle-aged rats, injections of higher doses of G and D decreased the serum cholesterol levels, as did testosterone injection, and brought about an increase in serum triglycerides similar to that observed after estradiol treatment.
Asunto(s)
Colesterol/sangre , Genisteína/administración & dosificación , Isoflavonas/administración & dosificación , Fitoestrógenos/administración & dosificación , Triglicéridos/sangre , Factores de Edad , Animales , Colesterol/metabolismo , Genisteína/farmacología , Inhibidores de Crecimiento/administración & dosificación , Inhibidores de Crecimiento/farmacología , Inyecciones Subcutáneas , Isoflavonas/farmacología , Masculino , Orquiectomía , Fitoestrógenos/farmacología , Ratas , Ratas Wistar , Testosterona/administración & dosificación , Testosterona/farmacología , Triglicéridos/metabolismoRESUMEN
Nowadays, the Colebrook equation is used as a mostly accepted relation for the calculation of fluid flow friction factor. However, the Colebrook equation is implicit with respect to the friction factor (λ). In the present study, a noniterative approach using Artificial Neural Network (ANN) was developed to calculate the friction factor. To configure the ANN model, the input parameters of the Reynolds Number (Re) and the relative roughness of pipe (ε/D) were transformed to logarithmic scales. The 90,000 sets of data were fed to the ANN model involving three layers: input, hidden, and output layers with, 2, 50, and 1 neurons, respectively. This configuration was capable of predicting the values of friction factor in the Colebrook equation for any given values of the Reynolds number (Re) and the relative roughness (ε/D) ranging between 5000 and 10(8) and between 10(-7) and 0.1, respectively. The proposed ANN demonstrates the relative error up to 0.07% which had the high accuracy compared with the vast majority of the precise explicit approximations of the Colebrook equation.
Asunto(s)
Fricción , Hidrodinámica , Redes Neurales de la ComputaciónRESUMEN
About 80 years have passed since the first cases of organophosphate induced delayed polyneuropathy (OPIDP), as the consequence of human poisoning with certain organophosphorus compounds, were described in the literature. OPIDP is a relatively rare neurodegenerative disorder in humans characterized by loss of function, ataxia and paralysis of distal parts of sensory and motor axons in peripheral nerves and ascending and descending tracts of spinal cord appearing 2-3 weeks after exposure or later. The molecular target for OPIDP is considered to be an enzyme in the nervous system known as neuropathy target esterase (NTE). This review discusses OPIDP in man with emphasis on clinical presentation, pathogenesis, molecular mechanisms, and possibilities for prevention/therapy.
Asunto(s)
Síndromes de Neurotoxicidad/etiología , Organofosfatos/toxicidad , Polineuropatías/inducido químicamente , Animales , Esterasas/metabolismo , Humanos , Síndromes de Neurotoxicidad/diagnóstico , Síndromes de Neurotoxicidad/tratamiento farmacológico , Fosforilación , Polineuropatías/diagnóstico , Polineuropatías/tratamiento farmacológico , Polineuropatías/enzimologíaRESUMEN
A sensitive and accurate method, combining Soxhlet extraction, solid-phase extraction and capillary gas chromatography, is described for the quantitative determination of four new diterpenes (ent-trachyloban-3beta-ol, ent-18-hydroxy-trachyloban-3-one, ent-trachyloban-3-one and isopimara-7,15-dien-3beta-ol) from the leaves of Croton zambesicus. This is the first method describing the quantification of trachylobane diterpenes in a crude extract. It has been fully validated in order to be able to compare the diterpene composition in other samples of C. zambesicus, which is an important source of trachylobanes.
Asunto(s)
Cromatografía de Gases/métodos , Croton/química , Diterpenos/análisis , Diterpenos/química , Hojas de la Planta/química , Estructura Molecular , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
The soybean phytoestrogen, genistein, is increasingly consumed as an alternative therapeutic for age-related diseases, namely cardiovascular conditions, cancer and osteoporosis. However, despite the beneficial effects on health, concern has been raised that this isoflavone also acts as an endocrine-disrupting chemical. The aim of this study was to examine the effects of genistein on immunohistomorphometric features of pituitary adrenocorticotropic cells (ACTH) and blood concentrations of ACTH and corticosterone in orchidectomized middle-aged male rats. Sixteen-month-old Wistar rats were divided into sham-operated (SO), orchidectomized (Orx) and genistein-treated orchidectomized (Orx+G) groups. Genistein (30mg/kg/day) was administered subcutaneously for three weeks, while the control groups received the vehicle alone. ACTH cells were identified by the peroxidase-antiperoxidase (PAP) immunohistochemical procedure. Circulating concentrations of ACTH and corticosterone were measured by immunoassay. Orchidectomy reduced (p<0.05) the cell volume and the relative volume of ACTH cells in comparison to SO rats. Genistein treatment further decreased (p<0.05) these morphometric parameters and reduced (p<0.05) circulating ACTH and corticosterone concentrations by more than 20 percent in comparison to both Orx and SO rats. In conclusión, genistein modulated the immunohistomorphometric features of ACTH cells and decreased blood ACTH and corticosterone levels, which supports evidence that this isoflavone affects the hypothalamic-pituitary-adrenal axis and suppresses glucocorticoid hormone secretion.