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1.
Zhang L  Han L  Sun X  Gao D  Qin J  Wang J 《Fitoterapia》2012,83(4):678-689
The clinical application of salvianolic acid B (Sal B), a potential therapeutic agent for cardiovascular diseases isolated from Salvia miltiorrhiza, is greatly restricted by its short half-life and low bioavailability. To improve therapeutic effects and prolong the systemic circulation time of Sal B, liposomes, composed of soybean phosphatidylcholine and cholesterol were prepared by reverse-phase evaporation method. In addition, polyethylene glycol 2000-disteroylphosphoethanolamine (PEG-DSPE 2000) was included to give steric barrier to liposomes. A central composite design was employed to optimize liposomal formulation with high encapsulation efficiency and small particle size. Physicochemical characteristics such as particle size, zeta potential, encapsulation efficiency and in vitro release were investigated. In vivo pharmacokinetic properties of Sal B in beagle dogs and the effect of PEG on the blood circulation time of Sal B-loaded liposomes were also evaluated. An optimized formulation with encapsulation efficiency of 73.68% and mean particle size of 136.6nm were developed. Encapsulation of Sal B into conventional and PEGylated liposomes could prolong the half-life of Sal B by 5.8- and 17.5-fold and enhance the AUC(0-t) of Sal B by 6.7- and 13.3-fold compared with free Sal B, respectively. Therefore, the use of PEGylated liposomes could prolong the circulation time in blood and longevity effect of liposomes on Sal B was increased by PEG.  相似文献   

2.
Wu XD  Cheng JT  He J  Zhang XJ  Dong LB  Gong X  Song LD  Zheng YT  Peng LY  Zhao QS 《Fitoterapia》2012,83(6):1068-1071
A new benzophenone C-glycoside, malaferin A (1), and two new epicatechin derivatives, malaferin B (2) and malaferin C (3), together with five known compounds were isolated from Malania oleifera. In addition, (-)-epicatechin-3-O-benzoate (6) was isolated for the first time from a natural resource. Structures of 1-3 were determined on the basis of their spectroscopic methods, including 1D and 2D NMR techniques. All of the compounds were evaluated for anti-HIV activities.  相似文献   

3.
Cao X  Li CJ  Yang JZ  Wei BX  Yuan SP  Luo YM  Hou Q  Zhang DM 《Fitoterapia》2012,83(2):343-347
Four new neolignans, wilfordiols A-D (1-4), together with five known compounds (5-9), were isolated from an aqueous extract of the dried leaves of Tripterygium wilfordii. Their structures were determined by spectroscopic methods, including 1D and 2D NMR, HRESIMS, and CD experiments. The anti-inflammation activities of compounds 1-9 were evaluated by the inhibitory effect on NO production, in vitro.  相似文献   

4.
Xu JJ  Huang HQ  Zeng GZ  Tan NH 《Fitoterapia》2012,83(6):1125-1130
Two new sesquiterpenes deltoiden A (1) and deltoiden B (2), and two new lignans deltoignan A (9) and deltoignan B (10), together with 14 known compounds, including six sesquiterpenes 3-8 and three lignans 11-13, were isolated from the whole plant of Saussurea deltoidea. Compounds 3-8 and 11-17 were isolated for the first time from this plant. Their structures were established by spectroscopic analysis, including 2D-NMR spectroscopic techniques. Cytotoxicities of compounds 1-13 were tested against three cancer cell lines A549, Hela and SMMC-7721. Results showed that 5, 6 and 7 exhibited cytotoxicity against SMMC-7721 with the IC(50) values of 6.49, 9.53, 1.23 μg/ml, 5 and 7 against A549 with the IC(50) values of 4.99 and 5.35 μg/ml, 5, 6, 7, 13 against Hela with the IC(50) values of 1.40, 4.75, 0.93 and 5.42 μg/ml, respectively. The structure-activity relationships of sesquiterpenes 1-8 were discussed on the base of cytotoxic results.  相似文献   

5.
利用Mannich反应将黑荆树单宁固定在氯甲基化聚苯乙烯树脂表面,成功地制备出一种新型固化单宁大孔吸附树脂(MARIT),并通过正交试验得出适宜的合成条件.苯酚在MARIT上的平衡吸附数据符合Freundlich吸附等温方程.利用热力学函数关系计算了等量吸附焓、吸附自由能和吸附熵,等量吸附焓在8.95~13.41 kJ/mol之间,推测吸附过程为氢键吸附.比较MARIT对苯酚的水溶液和环己烷溶液中苯酚的吸附性能,及对溶液中苯酚、间苯二酚和邻硝基苯酚的吸附性能,进一步讨论了MARIT对苯酚吸附时的氢键作用.  相似文献   

6.
Heartwood extractives (nonstructural wood components) are believed to be formed from a combination of compounds present in the adjacent sapwood and materials imported from the phloem. The roles of local compounds and imported material in heartwood formation could have important implications for the wood quality of species having naturally durable wood. Stable isotope composition (delta(13)C) was analyzed to assess radial variation in sapwood extractives, and to estimate the relative importance of adjacent sapwood extractives and imported photosynthate in the formation of heartwood extractives. Cellulose and extractives from the outer 39 annual rings of six Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees were isolated and their delta(13)C composition determined. Although the extractives and the cellulose showed different absolute delta(13)C values, the patterns of change over time (as represented by the annual rings) were similar in most cases. Within an annual ring, carbon isotope ratios of extractives were correlated with the cellulose isotope ratio (R2 = 0.33 in sapwood, R2 = 0.34 in heartwood for aqueous acetone-soluble extractives; R2 = 0.41 in sapwood for hot-water-soluble extractives). These data suggest that some sapwood extractives are formed when the wood ring forms, and remain in place until they are converted to heartwood extractives many years later. Sapwood extractives appear to be important sources of materials for the biosynthesis of heartwood extractives in Douglas-fir.  相似文献   

7.
In the course to find a new whitening agent, we evaluated the methanol extract from bud of clove (Syzygium aromaticum) on melanin formation in B16 melanoma cells. Eugenol and eugenol acetate were isolated as the active compounds and showed melanin inhibition of 60% and 40% in B16 melanoma cell with less cytotoxicity at the concentration of 100 and 200 μg/mL, respectively. Furthermore, an essential oil prepared from the bud of clove, which contain eugenol and eugenol acetate as dominant components, showed melanin inhibition of 50% and 80% in B16 melanoma cells at the concentration of 100 and 200 μg/mL, respectively.  相似文献   

8.
9.
Li J  Zeng KW  Shi SP  Jiang Y  Tu PF 《Fitoterapia》2012,83(5):896-900
Two new compounds (S)-(+)-butyl-4-methylene-5-oxo-pyrrolidin-2-carboxylate (1) and (5-formylfuran-2-yl)methyl 4-hydroxy-2-methylenebutanoate (2), together with four known compounds (3-6) were isolated from the roots of Polygala tricornis Gagnep. Their structures were determined on the basis of 1D- and 2D-NMR experiments and by comparison with physical data of known compounds. All the isolated compounds were examined for their inhibitory effect on the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in BV-2 microglial cells, and compounds 1 and 2 exhibited pronounced inhibition on the NO production with IC(50) values of 14.1 μM and 1.77 μM, respectively.  相似文献   

10.
Chen HY  Ye XL  Cui XL  He K  Jin YN  Chen Z  Li XG 《Fitoterapia》2012,83(1):67-73
Generally, berberine, coptisine, palmatine, and jatrorrhizine were considered as the main bio-active compounds in Rhizoma Coptis (RC). Little attention was paid to investigate the pharmacological activity of minor constituents in RC. The present study was designed to separate the minor compounds, and the cytotoxicity and antihyperglycemic effect of these compounds in HepG2 cells were also studied. Palmatine (1), berberine (2), coptisine (3), epiberberine (4), columbamine (5), and jatrorrhizine (6) from RC ethanol extract were isolated by high speed counter current chromatography (HSCCC) in one run. The remaining fraction (about 50% of extract in HSCCC) was further isolated by traditional column chromatography methods to yield magnoflorine (7), ferulic acid (8), and choline (9). Another four alkaloids, namely groenlandicine (10), berberrubine (11), oxyberberine (12), 8-oxo-coptisine (13), also were obtained from CHCl3 extracts. Especially, choline was first isolated from RC. Cell assay indicated that the minor fractions excluding compounds 1-6 showed obvious glucose lowering activity. In addition, the minor monomers also exhibited moderate glucose lowering activity. The combination of berberine and ferulic acid showed synergistic effect on antihyperglycemic. The combination of alkaloids 1-6 was same so. All compounds had different cytotoxicity in HepG2 cells within the test concentration. Of them, berberrubine showed the strongest cytotoxicity. The results suggested that combined action of variety constituents contributed to the antihyperglycemic effets and low cytotoxicity of RC extract in HepG2 cells.  相似文献   

11.
Wood treated with CCB (chromated copper borate) has an expected service life of 20–50 years, depending on conditions of service and method of treatment. After this period, treated wood is discarded as special waste. Due to toxic elements (Cu, Cr, and B) in such treated wood, burning and landfill disposal are not considered as environmentally sound solutions. Chemical extraction seems more promising. The principle of the method is to convert fixed biocides in wood into soluble form and leach them out of the wood. In order to elucidate this process, copper(II) sulfate, potassium dichromate, and CCB-treated samples were leached using five different agents, namely, water, an aqueous solution of oxalic or acetic acid, and an aqueous solution of oxalic or acetic acid with ammonia. Afterwards, the amounts of leached copper and chromium were determined. In a parallel experiment, electron paramagnetic resonance measurements of wet- and dry-leached and unleached samples were performed in order to determine the paramagnetic complexes that were formed. The highest chromium leaching was achieved with the aqueous solution of oxalic acid, as chromium was converted into water-soluble chromium oxalate. While the mixture of oxalic acid and ammonia resulted in the highest copper leaching, EPR observation revealed that in this case water-soluble complexes of copper, oxalic acid, and ammonia were formed. We found out that oxalates formation is not the only mechanism responsible for copper or chromium leaching. High acidity may play an important role too.  相似文献   

12.
通过干法无胶纤维板制造过程中对木材化学成分的转化和含量变化的研究,探讨了干法无胶纤维板的粘合机理。结果表明:①在热磨和热压过程中纤维素、半纤维素均部分发生水解,其水解单糖和游离单糖均能发生化学变化,生成糠醛类化合物;②在热磨和热压过程中木素的降解有利于纤维的粘合反应,并可以与糠醛类化合物生成树脂聚合物  相似文献   

13.
A new steroidal derivative, urs Stigmast-4, 20 (21), 23-trien-3-one and other four compounds were isolated from the leaves of Bryophyllum pinnatum. The structure of this new steroid was elucidated and established by standard spectroscopic methods. Carrageenan induced paw edema model was used for anti-inflammatory and acetic acid induced model used for analgesic activity. This new steroidal compound was found to be active in reducing inflammation (% inhibition 87.29 and 84.45 respectively) when compared with diclofenac. Further, it showed 75.72% protection in analgesic activity in acetic acid induced writhing test in mice. In conclusion the % inhibition against carrageenan induced rat paw edema and % protection against acetic acid induced writhings showed by new compound revealed that the anti-inflammatory and analgesic activity of aqueous extract B. pinnatum are mainly due to the presence of this steroidal compound.  相似文献   

14.
通过对徐州市林场侧柏人工纯林林下植被进行抽样调查,选取形成林火地面易燃物的主要杂草一年蓬、野燕麦为研究对象,用农达(草甘膦异丙胺盐41%水剂)、MCPA(2甲4氯钠盐13%水剂)、精禾草克(精喹禾灵5%乳油)3种防除效率较高的除草剂进行试验。结果表明,农达和MCPA不同浓度混合溶液具很好的防除效果。从生态环境、防除效果和经济成本等因素综合考虑,200倍农达稀释液与200倍MPCA稀释液的混合液对一年蓬和野燕麦防除效果最佳,可应用在森林防火隔离带的建设中。  相似文献   

15.
Kisiel W  Michalska K 《Fitoterapia》2006,77(5):354-357
Twelve known sesquiterpene lactones and the new guaianolide 10beta-methoxy-1alpha, 11beta,13-tetrahydrolactucin (10), together with three known phenolic acid esters were isolated from roots of Cichorium endivia var. crispum. The compounds were characterized by spectral methods.  相似文献   

16.
The aqueous extract of Hyptis suaveolens leaves was studied for their antinociceptive property in chemical and thermal models of nociception in mice. Oral administration of the aqueous extract (100, 200, and 400 mg/kg) dose-dependently reduced the number of writhings induced by acetic acid, decreased the licking activity of the early phase in formalin test and increased the reaction time in hot-plate test. The antinociceptive effect was significantly antagonized by naloxone (3 mg/kg; i.p.). Preliminary acute toxicity study showed that no animal death with doses up to 5 g/kg (p.o.).  相似文献   

17.
Kuang H  Sun S  Yang B  Xia Y  Feng W 《Fitoterapia》2009,80(1):35-38
A new megastigmane sesquiterpene glucoside named chaihuxinoside A (1), and a new indole diglucoside named chaihuxinoside B (9) were isolated from the aerial parts of Bupleurum chinense DC. along with eight known compounds. Structures of two new compounds were elucidated by a combination of chemical and spectroscopic methods. Chaihuxinosides A and B were characterized as 11-hydroxyl-4-en-3,9-dioxo- megastigmane-11-O-beta-D-glucopyranoside (1), and 3-carboxy-indole-10-O-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl ester (9), respectively.  相似文献   

18.
The dioxygen consumption by kraft lignin and several lignin model compounds during oxygen-alkali treatments were directly analyzed using a dioxygen fl owmeter. The average dioxygen consumption by 200 g of kraft lignin was about 3 moles. Because this value was as much as those obtained for monomeric phenolic lignin model compounds, guaiacol and vanillyl alcohol, it was postulated that not only phenolic but also nonphenolic moieties in kraft lignin are extensively oxidized. The dioxygen consumption by 0.5 moles (one equivalent of aromatic units) of a dimeric lignin model compound, guaiacylglycerol-β-guaiacyl ether (GG), was also similar to that for 1 mole of guaiacol and vanillyl alcohol, regardless of the type of the aromatic moiety, which supports the above postulation. The most plausible mechanism for the oxidation of nonphenolic moieties is the oxidation of side chains of residual β-O-4 substructures by active oxygen species. By this mechanism, nonphenolic moieties in kraft lignin and GG are converted into corresponding phenolic moieties, and the oxidation by dioxygen progresses. Part of this article was presented at the 13th International Symposium on Wood, Fiber, and Pulping Chemistry (13th ISWFPC), Auckland, New Zealand, May 2005  相似文献   

19.
A new oxazole (1) was obtained from Chinese insect medicine Aspongopus chinensis, along with three known N-acetyldopamine derivatives (2-4). Their structures were determined on the basis of NMR and ESI-MS analyses. The possible biosynthetic pathways of the isolated compounds are discussed. Cytotoxicities of those compounds against 10 selected cancer cells were measured in vitro.  相似文献   

20.
The methanolic extract of Verbascum sinuatum inflorescences and isolated compounds were tested for their antibacterial activity against 13 Gram(+) and Gram(-) bacteria and for their allelopathic activity against radish.  相似文献   

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