RESUMO
The uptake of stable cesium (133Cs) by Calla palustris was evaluated from four different substrates: water, soil, keramzit (a clay granule) and water with the addition of a potassium compound, after an eight days exposure to a solution of 0.5mM cesium chloride. Stable cesium was used because it is commonly supposed that its uptake by plants is the same of that of radiocesium (137Cs). The plants were differentiated in their parts (roots, healthy leaves, dead leaves and flowers) and analyzed with ICP-MS. The lowest average concentration of absorbed Cs was found in plants exposed in soil (0.7mg/kg, S.D.=96.8), while the highest in plants exposed in water (147mg/kg, S.D.=51.7). During the experiment the water planted plants removed 31.6% of provided Cs while those planted in soil removed only 0.06%. The addition of potassium to water was tested because of the competition effect that arises between these two elements: this effect was confirmed with the result that the average uptake in the presence of potassium was lower (41mg/kg in exposed plants, S.D.=76.1). The uptake was also lower in the solid-based substrates (soil and keramzit), because of the known tendency of Cs to bind with soil particles, thus becoming less available to plants. There was no evidence that the different parts of the plant showed different uptake effectiveness, or that the health of the plant (evaluated with a qualitative method) had any effect on the uptake of Cs.
Assuntos
Calla (Planta)/metabolismo , Césio/metabolismo , Poluentes Ambientais/metabolismo , Componentes Aéreos da Planta/metabolismo , Biodegradação Ambiental , Césio/farmacologia , Cloretos/farmacologia , Minerais , Raízes de Plantas/metabolismo , Potássio/metabolismo , Potássio/farmacologia , Solo , ÁguaRESUMO
Context The increasing problem of drug-resistant strains has led to the failure of current treatment regimens of Helicobacter pylori (HP) infection. Recently, a new treatment strategy has been developed to overcome the problem by using natural products in combination with antibiotics to enhance the treatment efficacy. Objective The antimicrobial combinatory effect of the aqueous extract of Hibiscus sabdariffa L. (Malvaceae) (AEHS) with antibiotics (clarithromycin, CLA; amoxicillin, AMX; metronidazole, MTZ) has been evaluated in vitro against HP strains. Materials and methods Hibiscus calyces (35 g) were brewed in 250 mL of boiled water for 30 min, and minimum inhibitory concentrations (MICs) were determined by agar dilution method. The checkerboard assay was used to evaluate the antimicrobial combinatory effect according to the sum of fractional inhibitory concentration (∑FIC) indices. Results In this study, AEHS exerted remarkable bacteriostatic effect against all HP strains tested with MICs values ranging from 9.18 to 16.68 µg/mL. Synergy effect of AEHS with CLA or MTZ was obtained against four of seven HP strains tested with ∑FIC ranging from 0.21 to 0.39. The additive effect of AEHS with AMX was obtained against five of seven HP strains tested with ∑FIC ranging from 0.61 to 0.91. Conclusion This study presents AEHS as a potent therapeutic candidate alone, or in combination with antibiotics for the treatment of HP infection.
Assuntos
Antibacterianos/farmacologia , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Amoxicilina/farmacologia , Antibacterianos/isolamento & purificação , Claritromicina/farmacologia , Sinergismo Farmacológico , Quimioterapia Combinada , Flores , Infecções por Helicobacter/microbiologia , Helicobacter pylori/crescimento & desenvolvimento , Helicobacter pylori/isolamento & purificação , Hibiscus/química , Humanos , Metronidazol/farmacologia , Testes de Sensibilidade Microbiana , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas MedicinaisRESUMO
UNLABELLED: In the last few decades, Hibiscus sabdariffa L. (Malvaceae; H. sabdariffa) has gained much attention in research field because of its potentially useful bioactivity as well as a great safety and tolerability. For decades, microbial, parasitic and cancer diseases remain a serious threat to human health and animals as well. To treat such diseases, a search for new sources such as plants that provide various bioactive compounds useful in the treatment of several physiological conditions is urgently needed, since most of the drugs currently used in the therapy have several undesirable side effects, toxicity, and drug resistance. In this paper, we aim to present an updated overview of in vitro and in vivo studies that show the significant therapeutic properties of the crude extracts and phytochemicals derived from H. sabdariffa as antimicrobial, antiparasitic, and anticancer agents. The future directions of the use of H. sabdariffa in clinical trials will be discussed. KEY WORDS: Hibiscus sabdariffa L. antimicrobial agents cancer preventive agents antiparasitic drugs natural products.
Assuntos
Anti-Infecciosos/uso terapêutico , Antineoplásicos/uso terapêutico , Hibiscus , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/uso terapêutico , Animais , Anti-Infecciosos/análise , Antineoplásicos/análise , Humanos , Compostos Fitoquímicos/análise , Fitoterapia , Extratos Vegetais/análiseRESUMO
Since the problem of bacterial resistance has become a serious problem worldwide, it was necessary to search for new active substances that can overcome the problem and enhance the treatment efficacy of bacterial infections. Numerous plant-derived essential oils exhibited significant antibacterial activities. This review aimed to summarize the most promising essential oils that exhibited remarkable antibacterial activities against various bacterial infections, including staphylococcal infections, Helicobacter pylori infections, skin infections, tuberculosis infection and dental bacterial infection. The synergy effect of essential oils in combination with antibiotics, as well as their role in the treatment of bacterial infections have been discussed. Essential oils can be used as models for further studies in vivo and clinical trials.
Assuntos
Antibacterianos/farmacologia , Óleos Voláteis/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
Since the problem of bacterial resistance has become a serious problem worldwide, it was necessary to search for new active substances that can overcome the problem and enhance the treatment efficacy of bacterial infections. Numerous plant-derived essential oils exhibited significant antibacterial activities. This review aimed to summarize the most promising essential oils that exhibited remarkable antibacterial activities against various bacterial infections, including staphylococcal infections, Helicobacter pylori infections, skin infections, tuberculosis infection and dental bacterial infection. The synergy effect of essential oils in combination with antibiotics, as well as their role in the treatment of bacterial infections have been discussed. Essential oils can be used as models for further studies in vivo and clinical trials.
Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Óleos Voláteis/uso terapêutico , Sinergismo Farmacológico , Fitoterapia , Plantas/químicaRESUMO
OBJECTIVES: In this review, we highlight and summarise the most promising extracts, fractions and pure compounds as potential anti-herpes simplex virus (HSV) agents derived from microorganisms, marine organisms, fungi, animals and plants. The role of natural products in the development of anti-HSV drugs will be discussed. KEY FINDINGS: Herpes simplex viruses (HSV-1 and -2) are common human pathogens that remain a serious threat to human health. In recent years, a great interest has been devoted to the search for integrated management of HSV infections. Acyclovir and related nucleoside analogues have been licensed for the therapy that target viral DNA polymerase. Although these drugs are currently effective against HSV infections, the intensive use of these drugs has led to the problem of drug-resistant strains. Therefore, the search for new sources to develop new antiherpetic agents has gained major priority to overcome the problem. SUMMARY: Natural products as potential, new anti-HSV drugs provide several advantages such as reduced side effects, less resistance, low toxicity and various mechanisms of action. This paper aims to provide an overview of natural products that possess antiviral activity against HSV.