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以金线莲为材料,利用统计学实验设计方法对黄酮类物质的提取工艺进行了优化。选定液料比、乙醇浓度和时间三个因素的五个水平进行球面设计实验,建立黄酮提取率的二次回归方程,通过回归分析及岭脊分析得到优化提取组合条件。研究结果表明,当提取工艺条件为:液料比24,乙醇浓度63%,提取时间48 h时,黄酮提取率的最大预测值为1.107%,验证值为1.05%。葡萄糖耐受性试验结果表明:金线莲黄酮类萃取物能够提高正常小鼠对糖的耐受性。  相似文献   

3.
Eight compounds were isolated from the ethyl acetate- and n-butanol-soluble fractions of the ethanollc extract of the whole plant of Anoectochllus roxburghll(Wali.) Lindi. (Orchidaceee). On the basis of spectroscopic methods, the structures of these compounds were elucidated as quercetin-7-O-β-D-[6"-O-(trans-feruloyi)]- giucopyranosids (compound 1), 8-C-p-HydroxybenzyiquerceUn (compound 2), isorhamnetin-7-O-β-D- giucopyranoside (compound 3), isorhamnetin-3-O-β-D-giucopyranoside (compound 4), kaempferoi-3-O-β-D- giucopyranoside (compound 5), kaempferoi-7-O-β-D-giucopyranoside (compound 6), 5-hydroxy-3',4',7- trimethoxyfiavonoi-3-O-β-D-rutinoside (compound 7), and isorhamnetin-3-O-β-D-rutinoside (compound 8). Of the compounds isoisted, compound 1 was a new flavonoid giucoside and exhibited strong scavenging activity against the 1,1-diphenyi-2-picryihydrazyi free radical, whereas the ethanolic extract showed weak activity. Compounds 2-8 were obtained from this family for the first time.  相似文献   

4.
以福建产金线莲Anoectochilus roxburghii为材料,研究不同杀菌剂对金线莲病害防治及生长指标动态的影响。结果表明,多菌灵和甲基托布津对金线莲病害的防治效果较好,相对防治效果达到55.3%和47.1%;而百菌清和叶枯唑对病害的相对防治效果虽只有26.9%和5.3%,但二者处理对金线莲的茎粗和叶面积的增长有明显的促进作用。精甲霜·锰锌和乙蒜素在病害防治及促进生长指标方面无突出表现。  相似文献   

5.
考察4~9个月移栽月龄的广西金线莲Anoectochilus roxburghii生物学性状和多糖、多酚、黄酮含量的变化。结果表明,广西金线莲生物量随着移栽月龄的增加呈一定的增长,以移栽9月龄最高;多糖含量的变化趋势为先下降后上升,近似“V”字形,9月龄与4月龄无明显差异,4月龄含量呈现最高值;多酚和总黄酮含量均以6月龄最高。  相似文献   

6.
金线莲外植体筛选及愈伤组织诱导研究   总被引:2,自引:0,他引:2  
以金线莲茎段、叶片、茎片、不定芽为试材,分别在添加6-BA、ZT、NAA、KT 5个不同处理的MS及1/2MS培养基上培养,诱导愈伤组织。结果表明,以茎段、茎片、不定芽为外植体,在MS + 6-BA 2.0 mg/L + NAA0.5 mg/L、MS + NAA 2.0 mg/L + KT 0.1 mg/L和MS + 6-BA 2.0 mg/L + NAA 0.5 mg/L + ZT 0.2 mg/L培养基中培养,均能成功诱导愈伤组织。不定芽为诱导愈伤组织最佳外植体,最佳培养基为MS + 6-BA 2.0 mg/L + NAA 0.5 mg/L + KT 0.2 mg/L。  相似文献   

7.
金线莲生物学特性及生境特点的研究   总被引:1,自引:0,他引:1  
作者对福建野生金线莲资源进行调查和多点人工栽培试验观察,摸清了其分布、种类,阐述了野生金线莲生长发育习性及其所需的环境条件,为人工栽培提供了科学依据。  相似文献   

8.
金线莲挥发油化学成分的研究   总被引:7,自引:0,他引:7  
采用水蒸气蒸馏法提取花叶开唇兰挥发油,用GC毛细管柱进行分析,归一化法测定其相对含量,并用GC-MS法鉴定化学成分。检出182个成分,鉴定出73个化合物,占挥发油总量的92.64%,主要成分为:正十六烷酸(25.22%)、(Z,Z)-9,12-十八碳二烯酸甲酯(6.47%)、11,14,17-二十碳三烯酸甲酯(4.42%)、(Z,Z)-9,12-十八碳二烯酸(15.35%)和(Z,Z,Z)-9,12,15-十八碳三烯酸甲酯(13.64%)。  相似文献   

9.
采用湿式消解法对金线莲药材进行处理,石墨炉原子吸收光谱法测定其铅(Pb)、铜(Cu)、镉(Cd)等重金属元素含量。结果表明,Pb、Cu、Cd 三种元素的原子化温度分别是2100、2200和1800 ℃,灰化温度分别是400、800和250 ℃。Pb、Cu、Cd三种元素的检出限分别为0.47、0.50、0.62 μg·L-1,其加标回收率在92.7%~94.0%之间,平均相对标准偏差为1.71%,说明仪器精密度良好,湿式消解-石墨炉原子吸收光谱法能有效测定金线莲药材中Pb、Cu、Cd含量。  相似文献   

10.
通过对福建南靖金线莲产业进行调研, 分析其产业发展优势及存在问题, 提出今后的发展对策, 以期为南靖金线莲发展提供参考。调研表明: 南靖具有发展金线莲产业的天然优势,产业已成规模,产生了一定的经济、社会效益,但也存在产业集群度低、标准化战略缺失、科技投入不足、产业链延伸不够等问题。笔者认为,发展南靖金线莲应培育产业集群,走联合发展道路;实施区域品牌战略,推进标准化进程;开发产品,拓展产业链;加大科技投入,提升产业水准。  相似文献   

11.
Lipase-catalyzed synthesis of fatty acid sugar esters through direct esterification was performed in 2-methyl 2-butanol as solvent. Fructose and saturated fatty acids were used as substrates and the reaction was catalyzed by immobilized Candida antarctica lipase. The effect of the initial fructose/acyl donor molar ratio and the carbon-chain length of the acyl donor as well as their reciprocal interactions on the reaction performance were investigated. For this purpose, an experimental design taking into account variations of the molar ratio (from 1:1 to 1:5) and the carbon-chain length of the fatty acid (from C8 to C18) was employed. Statistical analysis of the data indicated that the two factors as well as their interactions had significant effects on the sugar esters synthesis. The obtained results showed that whatever the molar ratio used, the highest concentration (73 g l−1), fructose and fatty acid conversion yields (100% and 80%, respectively) and initial reaction rate (40 g l−1 h−1) were reached when using the C18 fatty acid as acyl donor. Low molar ratios gave the best fatty acid conversion yields and initial reaction rates, whereas the best total sugar ester concentrations and fructose conversion yields were obtained for high molar ratios.  相似文献   

12.
The O‐acyl isopeptide method was developed for the efficient preparation of difficult sequence‐containing peptide. Furthermore, development of the O‐acyl isodipeptide unit for Fmoc chemistry simplified its synthetic procedure by solid‐phase peptide synthesis. Here, we report a novel isodipeptide unit for Boc chemistry, and the unit was successfully applied to the synthesis of amyloid β peptide. Combination of Boc chemistry and the isodipeptide unit would be an effective method for the synthesis of many difficult peptides. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

13.
From peeled fruits of Musa paradisiaca (banana, vegetable variety), two new acyl steryl glycosides, sitoindoside-III and sitoindoside-IV, and two new steryl glycosides, sitosterol gentiobioside and sitosterol myo-inosityl-β-D-glucoside, have been isolated by gradient solvent extraction and extensive chromatography (CC, prep. TLC, GC and HPLC). The compounds have been characterized by comprehensive spectroscopic analyses (IR, 1H NMR, GC, mass spectra, [α]D) and crucial chemical transformation. Additionally, seasonal variations of the total sterols, free sterols, steryl esters, steryl glycosides and acyl steryl glycosides in the active samples of banana have been analysed. The results provide a basis for the observed fluctuations in the anti-ulcerogenic activity of the extracts, in different seasons, and the importance of appropriate formulation of the pure principles to optimize the activity.  相似文献   

14.
Two new 3-alkylpyridine alkaloids, pyrinodemins E (1) and F (2), were isolated from an Okinawan marine sponge Amphimedon sp. and the structures of 1 and 2 were elucidated on the basis of spectroscopic data. Pyrinodemins E (1) and F (2) were novel 3-alkylpyridine alkaloids possessing a 4-(methoxyamino)piperidinone moiety and an indol-3-glyoxylamide moiety, respectively. Pyrinodemin E (1) showed cytotoxicity against P388 and L1210 murine leukemia cells.  相似文献   

15.
Previous reports on the alkaloids of Z. leprieurii, Z. lemairei and Z. rubescens are reviewed. The alkaloids from nine specimens collected in Ghana have been examined chromatographically and the implications of the findings discussed, with special reference to the distinction between Z. leprieurii and Z. rubescens. In addition three further compounds, dihydrochelerythrine, lupeol and sesamin are reported for the first time from Z. leprieurii. The overall value of alkaloids as systematic markers in Zanthoxylum in Africa is briefly discussed.  相似文献   

16.
From the bark of Schefflera octophylla was isolated a series of triterpene fatty acid esters with the carbon numbers 16–21 and 23–29 in the fatty acid part. Oleanolic acid and 3α-hydroxy-lup-20(29)-ene-23,28-dioic acid were also identified.  相似文献   

17.
Catalytic asymmetric synthesis of alpha,beta-epoxy esters and alpha,beta-epoxy carboxylic acid derivatives is described. Catalytic asymmetric epoxidation of alpha,beta-unsaturated carboxylic acid imidazolides using La-BINOL-Ph(3)As=O complex gave the corresponding alpha,beta-epoxy peroxy tert-butyl esters, which were directly converted to the alpha,beta-epoxy methyl esters by adding methanol to the reaction. This catalytic system had broad generality for epoxidation of various substrates. With the use of 5-10 mol% of the catalyst, both beta-aryl and beta-alkyl-substituted-alpha,beta-epoxy methyl esters were obtained in up to 91% yield and in up to 93% enantiomeric excess. In addition, efficient transformations of alpha,beta-epoxy peroxy tert-butyl esters into the alpha,beta-epoxy amides, alpha,beta-epoxy aldehydes, and gamma,delta-epoxy beta-keto esters are also reported.  相似文献   

18.
The enantioselective hydrogenation of methyl or ethyl pyruvate over cinchona‐platinum catalyst system (Orito's reaction) is one of the most intensively studied heterogeneous catalytic asymmetric hydrogenation reactions. Studies aiming at systematic changes of the chiral template have played a crucial role in creating hypotheses for the mechanism of Orito's reaction. It is very important to clarify which structural unit of the alkaloid takes part in the enantiodifferentiation, and learn about the role of the different structural units of chiral templates. In this article, we made an attempt to describe the behavior of natural alkaloids, their synthetic derivatives, and analogues as chiral templates in the heterogeneous catalytic asymmetric hydrogenation of activated ketones. Chirality, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

19.
Seven benzophenanthridine alkaloids, 1-7, were isolated from the roots of Zanthoxylum nitidum. Among them, two novel alkaloids, named (R)-8-[(R)-1-hydroxyethyl]dihydrochelerythrine (1) and 8-methoxynorchelerythrine (2), were structurally identified as new compounds on the basis of the spectroscopic analysis. Bioactivity evaluation showed that nitidine (3), dihydrochelerythrine (4), oxyavicine (5), 8-methoxychelerythrine (6), and 8-hydroxydihydrochelerythrine (7) exhibit comparable analgesic and anti-inflammatory effects as hydrocortisone.  相似文献   

20.
Synthetic peptides reproducing the helix‐loop‐helix (HLH) domains of the Id proteins fold into highly stable helix bundles upon self‐association. Recently, we have shown that the replacement of the dipeptide Val‐Ser at the loop–helix‐2 junction with the corresponding O‐acyl iso‐dipeptide leads to a completely unfolded state that only refolds after intramolecular ON acyl migration. Herein, we report on an Id HLH analog based on the substitution of the Pro‐Ser motif at the helix‐1–loop junction with the corresponding O‐acyl iso‐dipeptide. This analog has been successfully synthesized by solid‐phase Fmoc chemistry upon suppression of DKP formation. No secondary structure could be detected for the O‐acyl iso‐peptide before its conversion into the native form by ON acyl shift. These results show that the loop–helix junctions are determinant for the folded/unfolded state of the Id HLH domain. Further, despite the high risk of DKP formation, peptides containing O‐acyl iso‐Pro‐Ser/Thr units are synthetically accessible by Fmoc chemistry. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

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