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61.
A method for the extraction of valuable compounds from plants and flowers (viz. laurel, rosemary, thyme, oregano and tuberose) is proposed. The dynamic approach allows go-and-backward circulation of the extractant (ethanol) through the solid sample subjected to the action of an ultrasound probe (thus reducing sample amount and avoiding overpressure). A multivariate optimisation study and application of the optimum values of the variables to kinetics studies show that 10 min is sufficient to obtain extraction efficiencies that greatly surpass those provided by steam distillation for essential oils or superheated liquid extraction for these oils and other valuable compounds, with lower costs and higher quality of the extract. The extraction time of the proposed method is 176–165 min shorter than steam distillation and 31–20 min shorter than superheated liquid extraction, depending on the target compound.  相似文献   
62.
Medicinal plants have been the main remedy to treat various ailments for a long time and nowadays, many drugs have been developed from traditional medicine. This paper reviews some medicinal plants and their main constituents which possess anti-inflammatory activities useful for curing joint inflammation, inflammatory skin disorders, cardiovascular inflammation and other inflammatory diseases. Here, we provide a brief overview of quick and easy reading on the role of medicinal plants and their main constituents in these inflammatory diseases. We hope that this overview will shed some light on the function of these natural anti-inflammatory compounds and attract the interest of investigators aiming at the design of novel therapeutic approaches for the treatment of various inflammatory conditions.  相似文献   
63.
Higher plants are different from animals in many aspects, but the important difference may be that plants are more easily influenced by environment. Plants have a series of fine mechanisms for responding to environmental changes, which has been established during their long-period evolution and artificial domestication. The relationship between higher plants and environment is influenced mutually. The component in environment provides higher plants with nutrients for shaping themselves and higher plants simultaneously bring photosynthetic products and metabolites to surroundings, which is the most important part of natural circle. Photosynthetic products are realized mainly by physiological mechanisms, and microbiological aspects in environment (for instance, soil environment) impact the above processes greatly. The complete understanding of the relationship will extremely promote the sustainable utilization of plant resources and make the best use of its current potential under different scales.  相似文献   
64.
植物中酞酸酯的分析测定研究   总被引:5,自引:0,他引:5  
建立了二氯甲烷超声提取、小粒径硅胶住色谱项分离、UV-HPLC测定植物中酞酸酯的方法,简便、快速,可使酞酸酯与杂质有效分离,回收率为85%~101%。用于实际植物样品中酞酸酯的测定,结果满意。  相似文献   
65.
Two lichens and 12 green plants growing at a former arsenic roasting facility in Austria were analyzed for total arsenic by ICP–MS, and for 12 arsenic compounds (arsenous acid, arsenic acid, dimethylarsinic acid, methylarsonic acid, arsenobetaine, arsenocholine, trimethylarsine oxide, the tetramethylarsonium cation and four arsenoriboses) by HPLC–ICP–MS. Total arsenic concentrations were in the range of 0.27 mg As (kg dry mass)−1 (Vaccinium vitis idaea) to 8.45 mg As (kg dry mass)−1 (Equisetum pratense). Arsenic compounds were extracted with two different extractants [water or methanol/water (9:1)]. Extraction yields achieved with water [7% (Alectoria ochroleuca) to 71% (Equisetum pratense)] were higher than those with methanol/water (9:1) [4% (Alectoria ochroleuca) to 22% (Deschampsia cespitosa)]. The differences were caused mainly by better extraction of inorganic arsenic (green plants) and an arsenoribose (lichens) by water. Inorganic arsenic was detected in all extracts. Dimethylarsinic acid was identified in nine green plants. One of the lichens (Alectoria ochroleuca) contained traces of methylarsonic acid, and this compound was also detected in nine of the green plants. Arsenobetaine was a major arsenic compound in extracts of the lichens, but except for traces in the grass Deschampsia cespitosa, it was not detected in the green plants. In contrast to arsenobetaine, trimethylarsine oxide was found in all samples. The tetramethylarsonium cation was identified in the lichen Alectoria ochroleuca and in four green plants. With the exception of the needles of the tree Larix decidua the arsenoribose (2′R)‐dimethyl[1‐O‐(2′,3′‐dihydroxypropyl)‐5‐deoxy‐β‐D ‐ribofuranos‐5‐yl]arsine oxide was identified at the low μg kg−1 level or as a trace in all plants investigated. In the lichens an unknown arsenic compound, which did not match any of the standard compounds available, was also detected. Arsenocholine and three of the arsenoriboses were not detected in the samples. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
66.
67.
This plastic waste degrades into nanoparticles, which are referred to as nanoplastics (NPs) pollutants, due to faulty reuse and recycling processes. These micro and nano plastic pollutants have the ability to absorb and interact with common pollutants and have a high surface area to volume ratio, which causes serious effects on the environment, especially plants. The size of pollutants is so small that they can cross the biological barriers and affect the cellular and molecular levels. Exposure to nanoplastics in photosynthetic species affects the growth and photosynthesis mechanism of the plants. Nanoplastics also affect humans through intake of the exposed plant materials. These pollutants can be plastic pellets, personal care products, marine coatings, synthetic textiles, etc. Plastic pollutants may enter the human body mainly through contaminated food and water. This review incorporates the toxicity of such pollutant and how their remediation is being done. The focus is also on the advancement of detection and remediation techniques.  相似文献   
68.
Herbs are an important part of traditional medicine in Poland. Therefore, the aim of this study was the determination of polonium 210Po in 48 selected medicinal herb samples from the Polish market. The activity concentrations of 210Po were measured using alpha spectrometry. The activity concentration of 210Po was in the range from 0.3?±?0.1 to 28.2?±?0.4 Bq kg–1. The obtained results were compared with corresponding studies conducted worldwide. A higher 210Po activity concentration was observed in the above-ground part of plants. The obtained results show that the highest 210Po activity concentration was observed in evergreen plants and winter-hardy plants. Yet even infusions with 2 g of the most contaminated herbs examined were considered to be radiologically safe.  相似文献   
69.
脉冲电场介导的植物空气负离子发射的倍增效应及其意义   总被引:4,自引:0,他引:4  
介绍了空气负离子(NAI)的物理概念及其在空气净化中的作用,讨论了正常生态条件下空气中NAI的来源.通过实验结果说明了脉冲电场可以使植物产生NAI发射的倍增效应,分析了其产生的机理.  相似文献   
70.
Zizyphus lotus L. (Desf.) (Z. lotus) is a medicinal plant largely distributed all over the Mediterranean basin and is traditionally used by Moroccan people to treat many illnesses, including kidney failure. The nephrotoxicity of gentamicin (GM) has been well documented in humans and animals, although the preventive strategies against it remain to be studied. In this investigation, we explore whether the extract of Zizyphus lotus L. (Desf.) Fruit (ZLF) exhibits a protective effect against renal damage produced by GM. Indeed, twenty-four Wistar rats were separated into four equal groups of six each (♂/♀ = 1). The control group was treated orally with distilled water (10 mL/kg); the GM treated group received distilled water (10 mL/kg) and an intraperitoneal injection of GM (80 mg/kg) 3 h after; and the treated groups received ZLF extract orally at the doses 200 or 400 mg/kg and injected intraperitoneally with the GM. All treatments were given daily for 14 days. At the end of the experiment, the biochemical parameters and the histological observation related the kidney function was explored. ZLF treatment has significantly attenuated the nephrotoxicity induced by the GM. This effect was indicated by its capacity to decrease significantly the serum creatinine, uric acid, urea, alkaline phosphatase, gamma-glutamyl-transpeptidase, albumin, calcium, sodium amounts, water intake, urinary volume, and relative kidney weight. In addition, this effect was also shown by the increase in the creatinine clearance, urinary creatinine, uric acid, and urea levels, weight gain, compared to the rats treated only with the GM. The hemostasis of oxidants/antioxidants has been significantly improved with the treatment of ZLF extract, which was shown by a significant reduction in malondialdehydes levels. Histopathological analysis of renal tissue was correlated with biochemical observation. Chemical analysis by HPLC-DAD showed that the aqueous extract of ZLF is rich in phenolic compounds such as 3-hydroxycinnamic acid, catechin, ferulic acid, gallic acid, hydroxytyrosol, naringenin, p- coumaric Acid, quercetin, rutin, and vanillic acid. In conclusion, ZLF extract improved the nephrotoxicity induced by GM, through the improvement of the biochemical and histological parameters and thus validates its ethnomedicinal use.  相似文献   
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