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1.
研究了金不换鲜三七液特殊毒理学效应的致突变性。以小鼠骨髓细胞染色体畸变试验,小鼠睾丸减数分裂染色体畸变及小鼠致畸试验为指标,研究金不换鲜三七液的安全性。结果:(1)小鼠骨髓细胞染色体畸变试验:低,中,高3个剂量组小鼠肌髓细胞染色体畸变率分别为0.7%,0.2%和0.9%,与对照组相比无显著差异。阳性对照组染色体畸变率大大增高。(2)小鼠睾丸减数分别细胞染色体畸变;在本实验条例上,小鼠睾丸细胞染色体  相似文献   

2.
根据化学动力学原理,采用经典恒温加速实验结合溴加成法测定三七叶甙胶囊中皂甙的含量,通过线性回归分析,求出其在室温(25℃)下的有效期τ25℃09=53a。  相似文献   

3.
三七对血液系统作用的研究进展   总被引:13,自引:0,他引:13  
三七,为五加科(Araliacae)植物人参三七Panaxnotoginseng(Burk)F.H.Chen(P.Pseudoginseng Wall;P.SanchiHoo)的干燥根,别名田七.是我国名贵中草药之一,主要产于广西、云南等地。味甘微苦 ,性温。三七含有多种化学成分 ,其中三七皂甙 (简称PNG)为主要有效成分之一 ,其含量8%~12 %。PNG中包括三七皂甙A (R -A) ,三七皂甙B (R -B) ,三七皂甙C(R -C) ,三七皂甙D (R -D1) (R -D2) ,三七皂甙E (R -E) ,三七皂甙F(R -F)。经理化常…  相似文献   

4.
刘金磊  李典鹏  黄永林   《广西植物》2007,27(2):281-284
分别采用紫外分光光度比色法(UV-vis)和高效液相色谱法(HPLC)测定了不同产地,不同品种罗汉果中的总甙和甙V的含量。测定结果表明:同一品种不同产地罗汉果中总甙含量、甙V成分变化不大,不同品种的总甙、甜味成分V均有明显差别。  相似文献   

5.
甜菊含甙量的变异及R—A型良种的选育   总被引:1,自引:0,他引:1  
从甜味成分种类及含量的不同,研究甜菊实生群体和单株无性系的变化,从中选育优质甜味成分含量高的良种。主要结果:(1)在实生群体中,丰产株型(圆纺锤形株)占7.3%,其中,优质甜味成分R-A含量超过St含量的R-A型株占10.96%,它们的R-A含量变幅为3.3-12.0%。(2)R-A型良种J-2单株无生系在繁殖达2000万株时,叶片大小和含甙量均存在极显著差异,R-A含量变幅为4.5-12.2%。  相似文献   

6.
文山三七     
三七自古就是名贵的中药材,如《本草纲目》记载:“此药近时始出,南人军中用为金疮要药,云有奇功。又云:凡杖扑伤损,瘀血淋漓者,随即嚼烂,罨之即止,青肿者即消散。……故能治一切血病……”在我国古代,三七的主要用途为跌打损伤的外用圣药。现代研究发现,三七对心脑系统疾病有广泛的治疗作用。目前,已从三七中分离得到ZI种单体皂甙及黄酮类物质(0038%)、三七素(0.90%)、活性多糖(0.28%)等主要药用有效成分。三七中尚含有17种以上氨基酸(总氨基酸平均含量为7.73%),73种挥发油成分(0.40%…  相似文献   

7.
采用自制的同时蒸馏萃取装置提取文山三七叶的挥发油成分,然后用GC-MS法分析并鉴定了各组成及质量分数。挥发油中共鉴定出69个成分,占总峰面积的73.09。主要挥发性成分及面积归一化法测得含量为棕榈酸(27.36%)、亚油酸(10.68%)、亚麻醇(8.60%)、2,6-二叔丁基对甲基苯酚(4.67%)、1,3-环辛二烯(3.90%)、5.十八炔(2.31%)、植物醇(1.92%)、六氢化法尼基丙酮(1.39%)、斯巴醇(1.35%)等。  相似文献   

8.
甜菊含甙量的变异及R-A型良种的选育   总被引:3,自引:1,他引:2  
从甜味成分种类及含量的不同,研究甜菊(SteviarebaudianaBertoni)实生群体和单株无性系的变化,从中选育优质甜味成分含量高的良种。主要结果:(1)在实生群体中,丰产株型(圆纺锤形株)占7.3%,其中,优质甜味成分R-A含量超过St含量的R-A型株占10.96%,它们的R-A含量变幅为3.3~12.0%。(2)R-A型良种J-2单株无性系在繁殖达2000万株时,叶片大小和含甙量均存在极显著差异,R-A含量变幅为4.5~12.2%。(3)从R-A含量为3.86%的实生群体中选出R-A含量为7.04~12.03%的单株及从R-A含量为9.10%的良种单株无性系中选出R-A含量为10.15~12.15%的单株,它们的R-A含量均大幅度提高。  相似文献   

9.
三七根的微量成分(1)   总被引:3,自引:0,他引:3  
从三七根中分到1个新的微量皂甙,命名为三七皂甙R7,其结构经光谱分析和化学方法证明为人参二醇-3-O-β-D-葡萄吡喃糖甙;此外,还分到1个已知的炔烯类化合物,人能炔三醇。  相似文献   

10.
金不换鲜三七液对哺乳动物致突变和致畸安全性评价   总被引:3,自引:0,他引:3  
研究了金不换鲜三七液特殊毒理学效应的致突变性。以小鼠骨髓细胞染色体畸变试验、小鼠睾丸减数分裂染色体畸变及小鼠致畸试验为指标, 研究金不换鲜三七液的安全性。结果: (a) 小鼠骨髓细胞染色体畸变试验: 低、中、高3 个剂量组小鼠骨髓细胞染色体畸变率分别为0-7 % 、0-2% 和0-9 % , 与对照组相比无显著差异。阳性对照组染色体畸变率大大增高。(b) 小鼠睾丸减数分裂细胞染色体畸变: 在本实验条件下, 小鼠睾丸细胞染色体畸变率[ 包括性染色体单价体(X- YU) , 常染色体单价体(AU)] 在各实验组和对照组之间无显著差异。(c) 小鼠致畸试验: 小鼠口服金不换鲜三七液的累积剂量达15 g/kg 体重的1/10、1/5 和1/2 , 小鼠致畸试验也无显著差异。实验结果表明, 金不换鲜三七液安全无毒。  相似文献   

11.
Five novel oligosaccharides (tetra-, penta- and hexa-saccharides) were synthesized by glucosyltransfer from beta-D-glucose 1-phosphate to isokestose (O-beta-D-fructofuranosyl-(2-->1)-O-beta-D-fructofuranosyl-(2-->1)-alpha-D-glucopyranoside) or nystose (O-beta-D-fructofuranosyl-(2-->1)-O-beta-D-fructofuranosyl-(2-->1)-O-beta-D-fructofuranosyl-(2-->1)-alpha-D-glucopyranoside) using Thermoanaerobacter brockii kojibiose phosphorylase. The oligosaccharides were identified as 2(2-alpha-D-glucopyranosyl)(m)isokestose; [O-alpha-D-glucopyranosyl-(1-->2)](m)-O-[beta-D-fructofuranosyl-(2-->1)](2)-alpha-D-glucopyranoside: m=1, 2, and 3, and 2(2-alpha-D-glucopyranosyl)(n)nystose; [O-alpha-D-glucopyranosyl-(1-->2)](n)-O-[beta-D-fructofuranosyl-(2-->1)](3)-alpha-D-glucopyranoside: n=1 and 2 using gas liquid chromatography analysis of the methyl derivatives, and MALDI-TOF-MS and NMR measurements of the newly formed oligosaccharides. 1H, 13C NMR signals of each saccharide were assigned using 2D-NMR techniques, including COSY, HSQC, HSQC-TOCSY, HMBC, CH(2)-selected E-HSQC, and CH(2)-selected E-HSQC-TOCSY.  相似文献   

12.
Two new cyclic peptides, named sajaponicin C (1) and sajaponicin D (2), were isolated from the whole plants of Sagina japonica (Caryophyllaceae). Their structures were determined as cyclo(Pro(2)-Leu(2)-Tyr-Leu(1)-Phe(1)-Pro(3)-Phe(2)-Pro(1)) (1) and cyclo(Pro(1)-Pro(2)-Pro(3)-Pro(4)-Phe(1)-Gly-Thr-Ser-Phe(2)-Ile-Tyr) (2) on the basis of spectroscopic data, especially by two-dimensional (2D) NMR techniques.  相似文献   

13.
The structure of the mannan of Candida albicans NIH A-207 strain (serotype A) was investigated by adopting mild acetolysis followed by enzymolysis with an Arthrobacter GJM-1 exo-alpha-mannosidase. The resultant oligosaccharides, from pentaose to octaose (where manp = D-mannopyranose), were identified as manp beta (1----2)manp alpha (1----2)manp alpha (1----2)manp alpha (1----2)manp, manp beta (1----2)manp beta (1----2)manp alpha (1----2)manp alpha (1----2)- manp alpha (1----2)manp, manp beta (1----2)manp beta (1----2)manp beta (1----2)manp alpha (1----2)manp alpha (1----2)manp alpha (1----2)manp and manp beta (1----2)manp beta (1----2)manp beta (1----2)manp beta (1----2)manp alpha (1----2)manp alpha (1----2)manp alpha (1----2)manp, respectively. Analyses of alpha-linked oligosaccharides obtained by acetolysis under conventional conditions gave the same oligosaccharides, from biose to heptaose, as those obtained from the mannans of C. albicans NIH B-792 (serotype B) and J-1012 (serotype A, formerly serotype C).  相似文献   

14.
Torulaspora delbrueckii starin IFO 0955 was examined with respect to its structural and serological properties of the cell wall mannan (Td-0955-M). Td-0955-M revealed significant reactivities with sera from a commercially available factor serum kit (Candida Check) in ELISA. Td-0955-M was investigated for its chemical structure by acetolysis under conventional and mild conditions. NMR and GC techniques were used as analytical techniques. The mannooligosaccharide fractions eluted from a Bio-Gel P-2 column were found to consist of Man(alpha1-2)Man, M2, Man(alpha1-2)Man(alpha1-2)Man and Man(beta1-2)Man(alpha1-2)Man, M3, Man(alpha1-2)Man(beta1-2)Man(beta1-2)Man(alpha1-2)Man, M5, and a new mannoheptaose, which possesses the structure, Man(alpha1-2)Man(beta1-2)Man(beta1-2)Man(beta1-2)Man(beta1-2)Man(alpha1-2)Man, M7. The results of the inhibition ELISA showed that the M7 oligosaccharide significantly inhibited the reactivities in the Td-0955-M-factor serum systems.  相似文献   

15.
In our previous study, we indicated for the first time that C-28 hydroxylation plays a significant role in the metabolism of 1alpha, 25-dihydroxyvitamin D(2) [1alpha,25(OH)(2)D(2)] by identifying 1alpha,24(S),25,28-tetrahydroxyvitamin D(2) [1alpha,24(S),25, 28(OH)(4)D(2)] as a major renal metabolite of 1alpha,25(OH)(2)D(2) [G. S. Reddy and K-Y. Tserng Biochemistry 25, 5328-5336, 1986]. The present study was performed to establish the physiological significance of C-28 hydroxylation in the metabolism of 1alpha, 25(OH)(2)D(2). We perfused rat kidneys in vitro with 1alpha, 25(OH)(2)[26,27-(3)H]D(2) (5 x 10(-10)M) and demonstrated that 1alpha,24(R),25-trihydroxyvitamin D(2) [1alpha,24(R),25(OH)(3)D(2)] and 1alpha,24(S),25,28(OH)(4)D(2) are the only two major physiological metabolites of 1alpha,25(OH)(2)D(2). In the same perfusion experiments, we also noted that there is no conversion of 1alpha,25(OH)(2)D(2) into 1alpha,25,28-trihydroxyvitamin D(2 )[1alpha,25,28(OH)(3)D(2)]. Moreover, 1alpha,24(S),25,28(OH)(4)D(2) is not formed in the perfused rat kidney when synthetic 1alpha,25, 28(OH)(3)D(2) is used as the starting substrate. This finding indicates that C-28 hydroxylation of 1alpha,25(OH)(2)D(2) occurs only after 1alpha,25(OH)(2)D(2) is hydroxylated at C-24 position. At present the enzyme responsible for the C-28 hydroxylation of 1alpha, 24(R),25(OH)(3)D(2) in rat kidney is not known. Recently, it was found that 1alpha,25(OH)(2)D(3)-24-hydroxylase (CYP24) can hydroxylate carbons 23, 24, and 26 of various vitamin D(3) compounds. Thus, it may be speculated that CYP24 may also be responsible for the C-28 hydroxylation of 1alpha,24(R),25(OH)(3)D(2) to form 1alpha, 24(S),25,28(OH)(4)D(2). The biological activity of 1alpha,24(S),25, 28(OH)(4)D(2), determined by its ability to induce intestinal calcium transport and bone calcium resorption in the rat, was found to be almost negligible. Also, 1alpha,24(S),25,28(OH)(4)D(2) exhibited very low binding affinity toward bovine thymus vitamin D receptor. These studies firmly establish that C-28 hydroxylation is an important enzymatic reaction involved in the inactivation of 1alpha,25(OH)(2)D(2) in kidney under physiological conditions.  相似文献   

16.
1. Ethylmalonyl-CoA was found to be a substrate for methylmalonyl-CoA mutase from Propionibacterium shermanii, the product being mainly (2R)-methylsuccinyl-CoA along with some (2S)-diastereoisomer. 2. The relevant 1H-nuclear magnetic resonance signals of methylsuccinic acid and of its dimethyl ester were assigned to the diastereotopic methylene hydrogens using sterospecifically dideuterated specimens of known configuration. 3. [2(-2)H1]Ethylmalonyl-CoA was converted by methylmalonyl-CoA mutase in 2H2O mainly to (2R, 3S)-[3(-2)H1]methylsuccinyl-CoA. No dideuterated product was observed. 4. Starting from (1R)-[1(-2)H1]-ethathanol, (1S)-[1(-2)H1]ethanol and [2H6] ethanol the following deuterated specimens of ethylmalonic acid were synthesised and characterised: (3S)-[3(-2)H1], (3R)-[3(-2)H1] and [3(-2)H2, 4(-2)H3], respectively. 5. Conversion of (3S)-[3(-2)H1]-ethylmalonyl-CoA (70% 2H1 and 2% 2H2 species) on the mutase in water afforded mainly (2R)-[2(-2)H1]methylsuccinyl-CoA along with some (2S)-diastereoisomer. No deuterium loss was observed. 6. Methylmalonyl-CoA mutase converted (3R)-[3(-2)H1]ethylmalonyl-CoA (81% 2H1 and 2% 2H2 species) to the following methylsuccinyl-CoA species: 33% [3(-2)H1], the deuterium being in the threo position with respect to the methyl group; 21% [2(-2)H1]; 46% unlabelled. The ratio of the species with (2R) and (2S) configuration was about 60:40. 7. Reaction of [3(-2)H2, 4(-2)H3]ethylmalonyl-CoA (94.5% [2H5] species) with the mutase gave the following labelled methylsuccinyl-CoA species:53.4% [methyl-2H3, 2(-2)H1, 3(-2)H1], the 3-deuterium being in the threo position with respect to the methyl group; 37.6% [methyl-2H3, 2(-2)H1]; 5% [methyl(-2)H3, 2(-2)H1, 2(-2)H1, 3(-2)H1] the 3-deuterium being in erythro position with respect to the methyl group; 4% [methyl(-2)H3, 3(-2)H1]. The ratio of the species with (2R) and (2S) configuration was about 70:30. 8. Implications of these findings for the mechanism of the rearrangements catalysed by coenzyme B12 are discussed.  相似文献   

17.
Recombinant I(1)(PP2A) and I(2)(PP2A) did not affect the activity of the catalytic subunit of protein phosphatase 1 (PP1(C)) with (32)P-labeled myelin basic protein, histone H1, and phosphorylase when assayed in the absence of divalent cations. However, in the presence of Mn(2+), I(1)(PP2A) and I(2)(PP2A) stimulated PP1(C) activity by 15-20-fold with myelin basic protein and histone H1 but not phosphorylase. Half-maximal stimulation occurred at 2 and 4 nM I(1)(PP2A) and I(2)(PP2A), respectively. Moreover, I(1)(PP2A) and I(2)(PP2A) reduced the Mn(2+) requirement by about 30-fold to 10 microM. In contrast, PP1(C) activity was unaffected by I(1)(PP2A) and I(2)(PP2A) in the presence of Co(3+) (0.1 mM), Mg(2+) (2 mM), Ca(2+) (0.5 mM), and Zn(2+) (0.1 mM). Following gel filtration chromatography on Sephacryl S-200 in the presence of Mn(2+), PP1(C) coeluted with I(1)(PP2A) and I(2)(PP2A) in the void volume. However, when I(1)(PP2A) and I(2)(PP2A) or Mn(2+) were omitted, PP1(C) emerged with a V(e)/V(0) of approximately 1.6. The results demonstrate that I(1)(PP2A) and I(2)(PP2A) associate with and modify the substrate specificity of PP1(C) in the presence of physiological concentrations of Mn(2+). A novel role is suggested for I(1)(PP2A) and I(2)(PP2A) in the reciprocal regulation of two major mammalian serine/threonine phosphatases, PP1 and PP2A.  相似文献   

18.
FTY720 phosphate (FTY720P) is a high potency agonist for all the endothelial differentiation gene family sphingosine 1-phosphate (S1P) receptors except S1P receptor subtype 2 (S1P(2)). To map the distinguishing features of S1P(2) ligand recognition, we applied a computational modeling-guided mutagenesis strategy that was based on the high degree of sequence homology between S1P(1) and S1P(2). S1P(2) point mutants of the ligand-binding pocket were characterized. The head group-interacting residues Arg3.28, Glu3.29, and Lys7.34 were essential for activation. Mutation of residues Ala3.32, Leu3.36, Val5.41, Phe6.44, Trp6.48, Ser7.42, and Ser7.46, predicted to interact with the S1P hydrophobic tail, impaired activation by S1P. Replacing individual or multiple residues in the ligand-binding pocket of S1P(2) with S1P(1) sequence did not impart activation by FTY720P. Chimeric S1P(1)/S1P(2) receptors were generated and characterized for activation by S1P or FTY720P. The S1P(2) chimera with S1P(1) sequence from the N terminus to transmembrane domain 2 (TM2) was activated by FTY720P, and the S1P(2)(IC1-TM2)(S1P1) domain insertion chimera showed S1P(1)-like activation. Twelve residues in this domain, distributed in four motifs a-d, differ between S1P(1) and S1P(2). Insertion of (78)RPMYY in motif b alone or simultaneous swapping of five other residues in motifs c and d from S1P(1) into S1P(2) introduced FTY720P responsiveness. Molecular dynamics calculations indicate that FTY720P binding selectivity is a function of the entropic contribution to the binding free energy rather than enthalpic contributions and that preferred agonists retain substantial flexibility when bound. After exposure to FTY720P, the S1P(2)(IC1-TM2)(S1P1) receptor recycled to the plasma membrane, indicating that additional structural elements are required for the selective degradative trafficking of S1P(1).  相似文献   

19.
The solution structure of the (6)F1(1)F2(2)F2 fragment from the gelatin-binding region of fibronectin has been determined (Protein Data Bank entry codes 1e88 and 1e8b). The structure reveals an extensive hydrophobic interface between the non-contiguous (6)F1 and (2)F2 modules. The buried surface area between (6)F1 and (2)F2 ( approximately 870 A(2)) is the largest intermodule interface seen in fibronectin to date. The dissection of (6)F1(1)F2(2)F2 into the (6)F1(1)F2 pair and (2)F2 results in near-complete loss of gelatin-binding activity. The hairpin topology of (6)F1(1)F2(2)F2 may facilitate intramolecular contact between the matrix assembly regions flanking the gelatin-binding domain. This is the first high-resolution study to reveal a compact, globular arrangement of modules in fibronectin. This arrangement is not consistent with the view that fibronectin is simply a linear 'string of beads'.  相似文献   

20.
A pair of enantiomerically pure quaternary ammonium salts with a chiral side chain, methyl-(R)-(1-methylpropyl)di(n-propyl)ammonium iodide 1 and methyl-(S)-(1-methylpropyl)di(n-propyl)ammonium iodide 2, and the related racemate, methyl-(rac)-(1-methylpropyl)di(n-propyl)ammonium iodide 3, were synthesized through a reductive alkylation procedure, starting from enantiomerically pure and, also, racemic forms of (rac)-(1-methylpropyl)amine. A spectroscopic chiroptical signature in solution was provided by the Raman optical activity spectra of compounds 1 and 2. The crystallographic structures of 1, 2, and 3 were examined by single crystal X-ray diffraction. 1 crystallizes in the tetragonal space group P4(3)2(1)2 (no. 96), a = b = 12.826 (2) A, c = 17.730 (2) A, V = 2916.9 (5) A(3), Z = 8, Flack coefficient 0.04 (2). 2 crystallizes in the tetragonal space group P4(1)2(1)2 (no. 92), a = b = 12.842 (1) A, c = 17.749 (2) A, V = 2927.0 (5) A(3), Z = 8, Flack coefficient 0.05 (2). The crystal structures and space groups for 1 and 2 are enantiomorphs and the crystallographic investigation confirmed the absolute configuration of the stereocenter in both compounds. 3 crystallizes in the monoclinic space group P2(1)/n(no. 14), a = 8.178 (1) A, b = 14.309 (2) A, c = 12.328 (2) A, beta = 96.811 (6) degrees, V = 1432.4 (2) A(3), Z = 4.  相似文献   

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