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1.
《Saudi Journal of Biological Sciences》2017,24(2):355-361
Evaluations of the therapeutic potential of medicinal plants and their components have been the subject of many studies. Furthermore, the biological activities of various plant species have been reported in various pieces of literature. Hyptis martiusii Benth (Lamiaceae), popularly known as “mad balm” is commonly found in the North, Southeast, and Northeast of Brazil. Its leaves are used ethnobiologically as antiulcerogenic, antimicrobial, antitumor and as insecticide. This study aimed to analyze the chemical composition of the essential oil of H. martiusii Benth (OEHM) by GC/MS as well as its possible topical activity as an antiedematogenic. This is verified by the models of ear edema induced by single (acute edema) and multiple (chronic edema) applications of croton oil topically, and systemically verified through the model of paw edema induced by carrageenan 1%. Doses of 50, 75 and 100 mg/kg OEHM were used in all tests. Chemical analysis of the oil revealed the 1,8-cineole (34.58%) and δ-carene (21:58%) as major components present in the essential oil. On the model of ear edema, acute and chronic OEHM in all the tested doses showed no significant antiedematogenic activity (p < 0.05). The systemic model of paw edema induced by carrageenin showed that a dose of 100 mg/kg effectively reduced swelling by 55.37% in the second hour evaluation when compared to the saline group. The anti-inflammatory systemic effect can give greater bioavailability of the components present in the essential oil and your interference in cytokines and leukotriene, thromboxane and prostaglandin biosynthesis. It is therefore concluded that OEHM presents systemic antiedematogenic activity but not topical activity at these doses. 相似文献
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《Saudi Journal of Biological Sciences》2017,24(4):875-882
The antimicrobial properties of essential oil from various Santolina species have not been investigated enough in the previous studies dealing with the biological activities of medicinal plants. In Tunisia, Santolina chamaecyparissus L. (Asteraceae) is the only Santolina species recorded and is used as vermifuge and emmenagogue. The chemical composition, antibacterial and antifungal properties of essential oils from the flowerheads and roots of spontaneous S. chamaecyparissus growing in Tunisia and the chemical composition which leads to the Tunisian chemotype are investigated here for the first time. Essential oils isolated by hydro distillation from flowerheads and roots of S. chamaecyparissus were analyzed by GC and GC/MS. Two methods served for antimicrobial assays of the essential oils: diffusion in a solid medium and micro-well dilution assay. Antifungal tests were carried out by the agar incorporation method. Sixty-seven constituents were identified from the essential oil of the flowerhead. The major constituents were: 1,8-cineole and β-eudesmol. Two non identified compounds were present at the highest concentration in root oil. Flowerhead oil was characterized by high contents in monoterpenes and sesquiterpenes oxygenated compounds. The flowerhead essential oil demonstrated potent of antibacterial properties against Pseudomonas aeruginosa ATCC and Enterococcus faecalis ATCC, with MIC of 0.625 μg/ml. These findings demonstrate that the flowerhead essential oils of S. chamaecyparissus have excellent antibacterial properties and for this reason they could contribute to decrease the problem of microbial resistance to antibiotics. 相似文献
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With the increasing popularity and use of medicinal herbs, their global demand has gained momentum. Developing countries, including China, India and South East Asian (SEA) countries, are the centres of origin and major global suppliers for most of these traditionally used medicinal herbs. One of the factors affecting the quality of these herbs is the contamination of heavy metals, mycotoxins, pesticide residues, polycyclic aromatic hydrocarbons (PAHs) and fumigants. These contaminants can accumulate during the cultivation, storage and processing of herbs and may have adverse effects on consumer health. There have been various reports regarding the presence of these contaminants in medicinal herbs. This review discusses the important contaminants of medicinal herbs, the frequency and magnitude of their occurrences, the potential causes of contamination and their regulatory limits in medicinal herbs. The major challenge in the international trade of medicinal herbs is the lack of common guidelines, regulatory measures and monitoring body to strictly enforce their regulation. 相似文献
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Maria Weinert Tharakeswari Selvakumar Travis S. Tierney Kambiz N. Alavian 《Journal of visualized experiments : JoVE》2015,(96)
Degeneration of mesencephalic dopaminergic (mesDA) neurons is the pathological hallmark of Parkinson’s diseae. Study of the biological processes involved in physiological functions and vulnerability and death of these neurons is imparative to understanding the underlying causes and unraveling the cure for this common neurodegenerative disorder. Primary cultures of mesDA neurons provide a tool for investigation of the molecular, biochemical and electrophysiological properties, in order to understand the development, long-term survival and degeneration of these neurons during the course of disease. Here we present a detailed method for the isolation, culturing and maintenance of midbrain dopaminergic neurons from E12.5 mouse (or E14.5 rat) embryos. Optimized cell culture conditions in this protocol result in presence of axonal and dendritic projections, synaptic connections and other neuronal morphological properties, which make the cultures suitable for study of the physiological, cell biological and molecular characteristics of this neuronal population. 相似文献
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Variations in the chemical composition of the essential oils of Minthostachys mollis Griseb. (Lamiaceae) collected in their natural habitat in Argentina were determined using GC-FID-MS analysis. Seventy five samples collected out of 40 wild plant populations in the Central and Northwestern Argentina during four years sampling, were analyzed. Principal Component Analysis was made on the chemical data showing that samples from Córdoba and San Luis belonged to the typical menthone – pulegone chemotype in accordance with previous reports; meanwhile samples from Tucumán, Salta and Catamarca showed the presence of different compositions, some previously unreported, mainly those detected in Tucumán province. In addition, cluster analysis was applied using Euclidean distance to measure the dissimilarity in the relative composition of samples from Tucumán, Salta and Catamarca, using Ward's method as the agglomeration technique. Five groups were retained with less than 10% of information loss: i) dihydrocarvone-carvone, ii) pulegone with absence of menthone, iii) carvacryl acetate-carvacrol, iv) limonene and v) linalool.It is worth mentioning that the compositions of the different chemotypes remained constant throughout the four years of collection and despite the highly diverse pattern of compositions revealed in this search, the typical chemotype was not found present northwards Córdoba and San Luis provinces. This is the first report of a deep study on natural populations of peperina throughout the whole distribution area in Argentina with consecutive sampling repetitions of the same populations during several years. 相似文献
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Abstract. Anopheles stephensi mosquitoes which had fed upon mice infected with Plasmodium yoelii nigeriensis malaria parasites produced significantly fewer eggs than mosquitoes fed on an uninfected mouse. Fecundity reduction was more pronounced when the bloodmeal contained malaria gametocytes and the mosquitoes developed oocysts. Egg production and haematin excretion were correlated for uninfected bloodfed mosquitoes; the presence of P.y. nigeriensis in the blood affected this relationship. Reduced fecundity was associated with a significant reduction of bloodmeal size (measured by haematin excretion) in mosquitoes which ingested gametocytaemic blood. The bloodmeal size in mosquitoes fed on parasitaemic blood without gametocytes was not significantly reduced. The use of haematin assays for determination of bloodmeal size in mosquitoes is discussed. 相似文献