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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
2.
《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
3.
4.
Silkworm hemolymph contains unique proteins that exhibit anti-apoptotic activity in mammalian cells. Among them, 30 K protein, which is one of the major anti-apoptotic molecules in silkworm hemolymph, has been well investigated. However, little is known about the biological functions of storage protein 1 (SP1), another main protein in silkworm hemolymph. In this study, the anti-apoptotic and anti-oxidative activities of SP1 were analyzed. A stable cell line expressing SP1 was constructed, which showed strong anti-apoptotic effect induced by staurosporine treatment. In addition, the cell line exhibited resistance to oxidative stress caused by hydrogen peroxide. For practical applications of SP1, recombinant SP1 was produced in Escherichia coli, and the supplementation of recombinant SP1 into culture medium exhibited anti-apoptotic and anti-oxidative activities. In addition, SP1 was found to be a cell-penetrating protein and localized in the cytosol as well as on the plasma membrane. The findings showed that SP1 itself is not an anti-oxidant; rather, it mediates intracellular anti-oxidative activity. In conclusion, the cellular resistance of SP1 to apoptosis and oxidative stress will provide a new strategy that could be utilized in the bio-industry for the production of biologics as well as for the development of anti-aging cosmetics. 相似文献
5.
Norhypersampsone A (1), a novel degraded polycyclic polyprenylated acylphloroglucinol (PPAP) derivative, 3-(2-hydroxy-7-methyl-3-methyleneoct-6-enyl)-5-isoprenyl-2,4,6-trihydroxybenzophenone (2), a new polyprenylated benzophenone derivative, and nine known compounds (3–11) were isolated from Hypericum sampsonii. Their structures were elucidated by comprehensive spectroscopic techniques. Compound 1 represents a novel cyclohexenone monocyclic-PPAP formed by losing the fragment of C-2–C-4 and the side chains at C-3 and C-5 in the phloroglucinol ring. The results of the inhibitory effects of compounds 1–11 on the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW 264.7 macrophages showed that compounds 1, 6–8, and 10 exhibited weak activities with IC50 values in the range of 20.3–37.1 μM. 相似文献
6.
Six pregnane alkaloids were isolated from the root of Sarcococca ruscifolia. The structures of three new alkaloids, namely, sarcorucinine E–G (1–3), were elucidated using spectroscopic methods, while three known alkaloids, namely, epipachysamine D, pachysamine M, and sarcovagine D, were identified by comparing their spectral data with those of the compounds reported earlier. All compounds were evaluated for their inhibitory activities against multiple types of cancer cells. 相似文献
7.
V.N. Pavlenko 《Journal of Russian & East European Psychology》2016,53(4):15-27
The article examines the problem of the relationship between universal and specific forms of cultural–historical development of mental processes. From different methodological approaches, the author prefers an activity approach which emphasizes genetic primacy of external practical activity. This approach allows, according to the author, universality of internalization and at the same time ethnic uniqueness of mental processes. The article clarifies the problem of internalization through two practical examples: 1) the development of mental counting actions and 2) the process of human goal setting. 相似文献
8.
《Bioorganic & medicinal chemistry》2014,22(3):1201-1207
Human rhinoviruses (HRVs) are the most common cause of viral respiratory infections and their complications. So far, no anti-viral agent has been approved for prevention or treatment of HRV infections. Pursuing our researches on small molecules with anti-rhinovirus activity, in this paper we describe the synthesis and in vitro anti-HRV 1B and 14 properties of new [2-(2H-chromen-3-yl)vinyl]pyridines and 3-[2-(pyridinyl)vinyl]-4H-chromen-4-ones. Generally, the synthesized compounds interfered with the replication of both serotypes at the micromolar or submicromolar concentrations. Preliminary results on their mechanism of action, performed on selected (E)-2-[2-(2H-chromen-3-yl)vinyl]pyridine, indicate an interference with the early step(s) of HRV 1B and 14 replication, probably at the uncoating level. 相似文献
9.
After a 2 h exposure of intact soybean nodules to high concentrations of NaCl (100mol m?3) or oxygen (8OkPa O2), morphometric computations carried out using an image analysis technique on semi-thin sections showed that both treatments induced a decrease in the area of the inner-cortex cells, which were then characterized by a tangential elongation. In contrast, no significant change in area occurred in the middle-cortex cells although their elongation decreased. Electron microscopic observations showed that in the inner-cortex cells changes included the presence of wall infoldings, an enlarged periplasmic space and a lobate nucleus whose chromatin distribution differed from that of the control. Structural changes also occurred in the endoplasmic reticulum, microbodies, mitochondria and plastids. From several of these changes, which are similar to those noted in osmocontractil cells in response to external stimuli, it can be hypothesized that the inner cortex may provide a potential mechanism for the control of oxygen diffusion through the nodules. 相似文献
10.
Biomass estimation models and allocation patterns of 14 shrub species in Mountain Luya,Shanxi, China 总被引:1,自引:0,他引:1 下载免费PDF全文
《植物生态学报》2017,41(1):115
Aims Shrub species have evolved specific strategies to regulate biomass allocation among various organs or between above- and belowground biomass and shrub biomass model is an important approach to estimate biomass allocation among different shrub species. This study was designed to establish the optimal estimation models for each organ (leaf, stem, and root), aboveground and total biomass of 14 common shrub species in Mountain Luya, Shanxi Province, China. Furthermore, we explored biomass allocation characteristics of these shrub species by using the index of leaf biomass fraction (leaf to total biomass), stem biomass fraction (stem to total biomass), root biomass fraction (root to total biomass), and root to shoot mass ratio (R/S) (belowground to aboveground biomass).
Methods We used plant height, basal diameter, canopy diameter and their combination as variables to establish the optimal biomass estimation models for each shrub species. In addition, we used the ratios of leaf, stem, root to total biomass, and belowground to aboveground biomass to explore the difference of biomass allocation patterns of 14 shrub species.
Important findings Most of biomass estimation models could be well expressed by the exponential and linear functions. Biomass for shorter shrub species with more stems could be better estimated by canopy area; biomass for taller shrub species with less stems could be better estimated by the sum of the square of total base diameter multiply stem height; and biomass for the rest shrub species could be better estimated by canopy volume. The averaged value for these shrub species was 0.61, 0.17, 0.48, and 0.35 for R/S, leaf biomass fraction, stem biomass fraction, and root biomass fraction, respectively. Except for leaf biomass fraction, R/S, stem biomass fraction, and root biomass fraction for shrubs with thorn was significantly greater than that for shrubs without thorn. 相似文献
Methods We used plant height, basal diameter, canopy diameter and their combination as variables to establish the optimal biomass estimation models for each shrub species. In addition, we used the ratios of leaf, stem, root to total biomass, and belowground to aboveground biomass to explore the difference of biomass allocation patterns of 14 shrub species.
Important findings Most of biomass estimation models could be well expressed by the exponential and linear functions. Biomass for shorter shrub species with more stems could be better estimated by canopy area; biomass for taller shrub species with less stems could be better estimated by the sum of the square of total base diameter multiply stem height; and biomass for the rest shrub species could be better estimated by canopy volume. The averaged value for these shrub species was 0.61, 0.17, 0.48, and 0.35 for R/S, leaf biomass fraction, stem biomass fraction, and root biomass fraction, respectively. Except for leaf biomass fraction, R/S, stem biomass fraction, and root biomass fraction for shrubs with thorn was significantly greater than that for shrubs without thorn. 相似文献