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1.
从唐古特瑞香(Daphne tangutica Maxim)95%乙醇提取物石油醚部分分离得到14个化合物,通过波谱学方法鉴定为β-谷甾醇(1)、β-胡萝卜苷(2)、2,4-二羟基-3,6-二甲基苯甲酸甲酯(3)、蛇床子素(4)、植物醇(5)、软脂酸(6)、stigmast-5-ene-3β,7α-diol(7)、(-)-lariciresinol(8)、daphnetin(9)、daphnoretin(10)、(-)-丁香树脂醇(11)、( )-medioresinol(12)、daphnelicin(13)和咖啡酸二十二酯(14)。  相似文献   

2.
本文对分布于日本的Agropyron tsukushiense(Honda)Ohwi var. transiense(Hack.)Ohwi(2n=6X=42)和分布于中国的Roegneria kamoji Ohwi(2n=6X=42)及其杂种F1(2n=6x=42)进行了形态学及细胞学的研究,并同时探讨了亲本种的亲缘关系。总体来看,亲本材料之间在形态上虽有差异但并不十分显著。杂种F1的形态特征介于其父、母本之间。在减数分裂过程中,亲本种和杂种F1的染色体配对行为均十分正常。但在检查了大量的成熟花粉和穗状花序之后,发现杂种F1有部份不育现象。上述研究结果表明A.tsuku-shiense var.transiens的三个染色体组与R.kamoji的三个染色体组同源。结合形态学和育性等方面的研究资料,作者认为上述两个材料仍应属于同一分类等级。但必须指出,由于长期的地理隔离,他们之间产生了一定的形态变异和生殖障碍。按照国际植物命名法规(ICBN)上述两个材料应组合:Roegneria tsukushiensis(Honda)B.R.Lu,Yen et J.L.Yang 及其变种var.transiens(Hack.)B.R.Lu,Yen et J.L.Yang comb.nov.  相似文献   

3.
Food Biophysics - In this research, the capability of different oleogelators (beeswax, rice bran wax and sunflower wax, stearic acid, octadecanol, γ-oryzanol+β-sitosterol mixture and...  相似文献   

4.
The phytochemical investigation of Sigmatanthus trifoliatus Huber ex Emmerich (Rutaceae) allowed the isolation and identification of the coumarins seselin, osthol, coumurrayin and braylin, besides the furoquinoline alkaloids evolitrine, dictamnine, γ-fagarine and skimmianine. Their chemical structures were determined based on MS, NMR analyses, and supported by comparison with those reported in the literature. The essential oils composition of leaves, roots, and trunk were also analyzed, showing the compounds b-Caryophyllene (33.2%), germacrene-D (28.1%) and bornyl acetate (14.7%) as main components, respectively. The chemotaxonomic significance of the isolated compounds was discussed.  相似文献   

5.
Oil sources characterized of increasing viscosity and polarity (flax-seed oil, sunflower oil, extra virgin olive oil, triolein, castor oil) were gelled by using mixtures of β-sitosterol and γ-oryzanol (5, 10 and 20 % w/w). The gelling time, thermal properties as well as structure characteristics were determined. As the oil viscosity increased the gelling time increased. The effect of oil type resulted more evident as the structurant concentration decreased. Samples containing 5 % of the most viscous and polar castor oil did not gelled over the entire experiment. When gels were formed, the firmness of samples decreased in concomitance with modifications of thermal data as the oil viscosity increased. During storage at 20 °C the gels became stronger as consequence of the progression of the aggregation among sterol-sterol ester assemblages. Once again, less structurants were in the mixture more evident was the influence of oil type. These results were attributed to the increase of the difficulty of β-sitosterol and γ-oryzanol molecules to pack together as the oil viscosity increased.  相似文献   

6.
Oxidative stress caused by neutrophils is an important pathogenic factor in trauma/hemorrhagic (T/H)-induced acute lung injury (ALI). Osthol, a natural coumarin found in traditional medicinal plants, has therapeutic potential in various diseases. However, the pharmacological effects of osthol in human neutrophils and its molecular mechanism of action remain elusive. In this study, our data showed that osthol potently inhibited the production of superoxide anion (O2•−) and reactive oxidants derived therefrom as well as expression of CD11b in N-formylmethionylleucylphenylalanine (FMLP)-activated human neutrophils. However, osthol inhibited neutrophil degranulation only slightly and it failed to inhibit the activity of subcellular NADPH oxidase. FMLP-induced phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (Akt) was inhibited by osthol. Notably, osthol increased the cAMP concentration and protein kinase A (PKA) activity in activated neutrophils. PKA inhibitors reversed the inhibitory effects of osthol, suggesting that these are mediated through cAMP/PKA-dependent inhibition of ERK and Akt activation. Furthermore, the activity of cAMP-specific phosphodiesterase (PDE) 4, but not PDE3 or PDE7, was significantly reduced by osthol. In addition, osthol reduced myeloperoxidase activity and pulmonary edema in rats subjected to T/H shock. In conclusion, our data suggest that osthol has effective anti-inflammatory activity in human neutrophils through the suppression of PDE4 and protects significantly against T/H shock-induced ALI in rats. Osthol may have potential for future clinical application as a novel adjunct therapy to treat lung inflammation caused by adverse circulatory conditions.  相似文献   

7.
Eight linear furocoumarins and three coumarins were isolated and identified from Thamnosma texana. They were xanthotoxin, imperatorin, bergapten, alloimperatorin methyl ether epoxide, heraclenin, isopimpinellin, psoralen, oxypeucedanin, and the coumarins herniarin, osthol and thamnosmin. The linear furocoumarins appear to be agents that account for the known photosensitizing properties of Thamnosma texana, and consequently its colloquial name, ‘blisterweed.’ This is the first report on the occurrence of imperatorin, heraclenin, oxypeucedanin, herniarin or osthol in any Thamnosma species.  相似文献   

8.
Abstract  Hexane, petroleum ether, chloroform, ethyl acetate, methanol and water extracts of Clausena anisata [(Willd.) Hook F. Ex Benth] leaves and roots were evaluated against Helicoverpa armigera (Hübner) for antifeedant activities. Antifeedant activity was confirmed, and was found to be higher in root extracts than those of the leaf. Chloroform and petroleum ether extracts of the root showed strongest antifeedant activities (DC50s [concentration (C) causing 50% deterrence compared with the control] 0.014% and 0.016% respectively), and root extracts were fractionated using silica gel column chromatography. One fraction of the chloroform and one of the petroleum ether root extracts was active; and on the basis of mass spectroscopy and 1H and 13C nuclear magnetic resonance spectral data, the active compounds in the two fractions were confirmed to be identical, and identified as osthol [2H-1-Benzopyran-2-one, 7-methoxy-8-(3-methyl-2-butenyl)]. The highest concentration of osthol was found in the chloroform root extract. Antifeedant activities of the root extracts, as measured by DC50 values, were highly correlated with their osthol contents. Approximately 99% of the variation in bioactivity of the root extracts could be accounted for by variation in osthol content; osthol therefore, appeared to be an antifeedant component of C . anisata to H. armigera . This may provide a new approach to managing this pest.  相似文献   

9.
中药川独活与浙独活根香豆素成分比较研究   总被引:1,自引:1,他引:0  
中药川独活系伞形科植物重齿当归,又名重齿毛当归(Angelica Inserrata(Shan et Yuan)Yuan et Shan)(A.pubescens Maxim.f.biserrata Shan et Yuan),为我国特产的常用药,广销国内外,有祛风、除湿、散寒、止痛等功用。四川、湖北、陕西等省都有栽培,野生重齿当归广泛分布于浙江、安徽、江西、四川等省。传统应用的中药独活为栽培的重齿当归,野生重齿当归仅在少数地区使用。为了弄清栽培与野生重齿当归间化学成分的差异,测定了它们的有效成分含量,为扩大利用野生重齿当归并为植物化学分类提供科学依据。  相似文献   

10.
Osthol is an active constituent isolated from the fruit of Cnidium monnieri (L.) Cusson (Apiaceae), and has obvious therapeutic effect on fatty liver, but its mechanisms are not yet understood completely. One potential link between adipose tissue and fatty liver may be circulating fatty acids. In the present study, the effect of osthol on fatty acid synthesis and release in cultured 3T3-L1 adipocytes was observed. Following treatment of adipocytes with osthol, the intracellular levels of free fatty acids (FFA) and triacylglycerols as well as cultured supernatant level of FFA were decreased, and some lipogenic gene and protein expressions were also decreased, while the peroxisome proliferator-activated receptor (PPAR) α/γ mRNA expressions were increased. Osthol-reduced lipogenic gene expressions were decreased or abrogated after pretreatment with specific inhibitor(s) of PPARα and/or PPARγ.  相似文献   

11.
From the above ground parts of Leionema ellipticum (Rutaceae), the new flavonoid 3,4′,5-trimethoxyflavone-7-O-α-rhamnoside, the 8-prenylated coumarin osthol, and the cinnamyl alcohol derivative boropinol-B were isolated and identified. Osthol is of systematic significance as coumarins with this substitution pattern have proved to be very common in species now assigned to Leionema. The presence of osthol in L. ellipticum is, therefore, supportive of a close relationship with other species of Leionema, despite the presence of a number of anomalous morphological features in the flowers.  相似文献   

12.
Protoplasts of a strain ofA. fœcalis incapable of utilizing β-sitosterol as carbon source for growth were fused with protoplasts ofA. oxydans — a strain capable of complete degradation of β-sitosterol. Five fusants showing morphology and pattern of transformation of C-19 steroids identical toA. Fœcalis were selected. Analysis of the fermentation broth containing β-sitosterol showed that the fusants were capable of utilizing β-sitosterol for growth but their pattern of metabolite formation from β-sitosterol was different from that ofA. oxydans. The study revealed that the protoplast fusion technique could be used for intergeneric transfer of genetic determinants linked to partial cleavage of β-sitosterol side chain toA. fœcalis fromA. oxydans.  相似文献   

13.
跌打止痛巴布膏体外透皮吸收实验研究   总被引:2,自引:0,他引:2  
本文采用Franz扩散池和离体裸鼠皮肤进行体外渗透试验,采用HPLC法同时测定蛇床子素和水杨酸甲酯的累积透皮量.以此研究跌打止痛巴布膏体外经皮渗透吸收特征.结果表明两种成分的体外经皮渗透均符合零级动力学方程,蛇床子素和水杨酸甲酯在15 h内的透过率分别为13.5%和49.62%.二者在皮肤的蓄积量分别为17.56%和23.23%.跌打止痛巴布膏中的有效成分在皮肤内有较强的蓄积作用,在15 h内药物持续恒速释放,为控释长效和局部作用的制剂.  相似文献   

14.
The influence of cholesterol and β-sitosterol on egg yolk phosphatidylcholine (EYPC) bilayers is compared. Different interactions of these sterols with EYPC bilayers were observed using X-ray diffraction. Cholesterol was miscible with EYPC in the studied concentration range (0-50 mol%), but crystallization of β-sitosterol in EYPC bilayers was observed at X ≥ 41 mol% as detected by X-ray diffraction. Moreover, the repeat distance (d) of the lamellar phase was similar upon addition of the two sterols up to mole fraction 17%, while for X ≥ 17 mol% it became higher in the presence of β-sitosterol compared to cholesterol. SANS data on suspensions of unilamellar vesicles showed that both cholesterol and β-sitosterol similarly increase the EYPC bilayer thickness. Cholesterol in amounts above 33 mol% decreased the interlamellar water layer thickness, probably due to "stiffening" of the bilayer. This effect was not manifested by β-sitosterol, in particular due to the lower solubility of β-sitosterol in EYPC bilayers. Applying the formalism of partial molecular areas, it is shown that the condensing effect of both sterols on the EYPC area at the lipid-water interface is small, if any. The parameters of ESR spectra of spin labels localized in different regions of the EYPC bilayer did not reveal any differences between the effects of cholesterol and β-sitosterol in the range of full miscibility.  相似文献   

15.
The ethanolic extract of the fresh roots of Heracleum canescens has afforded, besides sitosterol, osthol, methyl 3,4,5-trimethoxybenzoate and 11 furanocoumarins.  相似文献   

16.
We used a model intestinal solution to understand the mechanisms of cholesterol lowering by the addition of plant sterols. The experimental results of the competitive solubilization of cholesterol and β-sitosterol in vitro give useful information about these mechanisms. The states of the model intestinal solution as a solubilizer were analyzed by transmission electron microscopy (TEM) and dynamic light scattering (DLS) by changing the number of components, and the bile salt and phosphatidylcholine concentrations. There were aggregates of different sizes: liposomes and mixed micelles depending on their components and concentrations. The maximum solubilization of cholesterol increased from 0.2mM to 1.3mM when adding fatty compounds in the pure bile salts system, which is almost the same as the full components model intestinal solution. Therefore, an excessive intake of fatty compounds may also increase cholesterol absorption in vivo. Even if the components of the model intestinal solution were modified from the standard condition, there were not remarkable differences in the selectivity of cholesterol and β-sitosterol in competitive solubilization. With the addition of β-sitosterol, the maximum solubilization of cholesterol decreases to almost half of that in the system with only cholesterol, except for PC-rich systems. In general, the different structures of aggregates considerably influence the maximum solubilization of sterols but not the selectivity of cholesterol and β-sitosterol in the competitive solubilization. The Gibbs energy change (ΔG°) of the solubilization of β-sitosterol showed a more negative value than cholesterol by -4 to -6kJmol(-1), which indicates that β-sitosterol is energetically favored relative to cholesterol in the model intestinal solution, regardless of the different systems.  相似文献   

17.
The aim of this research was to describe the thermal behavior of β-sitosterol crystals in oil-suspensions with a focus on the role of water during heating. The suspensions were prepared by recrystallization in order to achieve a microcrystalline particle size. The structural changes together with the mechanical properties of the suspensions during heating were studied by using variable temperature X-ray powder diffractometry (VT-XRPD), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). Hydrated β-sitosterol crystals in an oil-suspension, dehydrated, despite the composition of the suspensions, at low temperatures. At high β-sitosterol concentration, the monohydrate crystal form changed partially to a hemihydrated form, and when only a small amount of water was initially incorporated, the hemihydrate crystal form dehydrated to a mostly anhydrate crystal form. The released water, which was immiscible in the surrounding oil, caused the recrystallization of hydrated β-sitosterol during cooling. This procedure indicated a reversible dehydration process. Structural and thermal analysis of β-sitosterol crystals in suspensions, together with mechanical analysis made it possible to understand various physical changes during heating. Published: October 19, 2005  相似文献   

18.
Abstract Sixth stadium nymphs of the grasshopper Schistocerca americana (Drury) (Orthoptera: Acrididae) were presented with spinach with or without added cholesterol or β-sitosterol, and the lengths of the first four meals were monitored. Spinach alone evoked a typical aversion learning pattern in which successive meals were of decreasing duration; however, when cholesterol or β-sitosterol was added the spinach remained acceptable. Nymphs fed spinach for 24h preferred glass-fibre discs with added cholesterol in a choice test, but nymphs fed wheat (an acceptable food) did not prefer cholesterol-treated or control discs. Nymphs pretreated with spinach did not distinguish between discs treated with stigmasterol (an unsuitable phytosterol for grasshoppers) and control discs. In no-choice tests, nymphs pretreated with spinach also fed significantly longer on discs with added 10% cholesterol or 1%β-sitosterol, compared to meals on discs with stigmasterol or sucrose controls. Detection of appropriate sterols is likely to involve a post-ingestive feedback mechanism, as significantly longer meals on discs treated with only sucrose resulted when spinach-fed nymphs, were force-fed gelatin capsules packed with β-sitosterol or cholesterol, compared with stigmasterol. Contact chemoreception is unlikely to play a role in this behaviour, as discs (lacking sucrose) treated with cholesterol, β-sitosterol, stigmasterol, or a chloroform control, all required similar numbers of contacts before feeding was initiated.  相似文献   

19.
金鱼藻的化学成分   总被引:8,自引:0,他引:8  
从金鱼藻(Ceratophyllum demersum L.)全草的乙醇提取物中分离鉴定了其中7个,分别为:苜蓿素-7-O-β-D-葡萄糖苷(1) , naringenin-7-O-β-D-葡萄糖苷(2) ,七叶内酯(3) ,β-谷甾醇(4) , 7α-羟基-β-谷甾醇(5) , 7α-甲氧基-β-谷甾醇(6) ,十六碳脂肪酸(7)。化合物(3)为首次从金鱼藻中分离得到。  相似文献   

20.
从金鱼藻( Ceratophyllum demersum L .) 全草的乙醇提取物中分离鉴定了其中7 个, 分别为: 苜蓿素-7- O-β- D-葡萄糖苷( 1) , naringenin-7- O-β- D-葡萄糖苷(2 ) , 七叶内酯(3) , β-谷甾醇(4 ) , 7α-羟基-β-谷甾醇(5) , 7α-甲氧基-β-谷甾醇(6) , 十六碳脂肪酸(7) 。化合物(3) 为首次从金鱼藻中分离得到。  相似文献   

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