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101.
Cell plating clone technique was employed to screen clone lines with high yield of oligosaccharins from culture cells of Panax ginseng C. A. Mey. Near 300 clone lines were obtained. The results from some clone lines analysed implied that these clone lines were significantly different in cell growth rate, oligosaccharins content and yield. Furthermore, there was a distinct correlation between oligosaccharins productivity and cell growth. A more stable high-yield oligosaccharin clone line PG-180 had been selected according to the characteristics of growth rate, oligosaccharin yield and peroxidases isozyme patterns during successive subculturing of 11 generations of clone lines. The mean growth rate of clone line PG-180 was 0. 495 g dry wt/L · d, and was 1.39 folds higher than to the original strain. Its mean content and yield of oligosaccharins were 14. 69 % dry wt and 2.183 g/L, which were 65 % and 132% respectively higher than those of the original strain. In comparing the time course of cell suspension culture between clone line PG-180 and the original strain, the optimal period for high oligosaccharin production from P. ginseng culture cells was approximately three weeks.  相似文献   
102.
Richter R  Basar S  Koch A  König WA 《Phytochemistry》2005,66(23):2708-2713
The volatile constituents of the roots of Panax ginseng C.A. Meyer have been investigated after hydrodistillation and analysed by means of different analytical methods. Besides several compounds already known three sesquiterpene hydrocarbons have been isolated from the essential oil. Structure elucidation of the bicyclic panaxene as well as of the tricyclic panaginsene and ginsinsene was performed by MS and NMR. They have been identified as (1R*,2S*,5S*)-2-ethenyl-1(1-methylethenyl)-2,6,6-trimethylbicyclo[3.2.0]heptane (panaxene), (1S*,8S*,11R*)-4,7,7,11-tetramethyltricyclo[6.3.0.0(1,5)]undec-4-ene (panaginsene) und (1R*,6R*,7R*)-3,7,10,10-tetramethyltricyclo[4.3.2.0(2,6)]undec-2-ene (ginsinsene).  相似文献   
103.
人参不同栽培群体遗传关系的RAPD分析   总被引:21,自引:0,他引:21  
用随机扩增多态DNA(RAPD)标记法对4个人参(Panax ginseg C.A.Meyer)栽培群体中存在较丰富的遗传多样性。分析一路参、三路参、系选品系59号、北京参等4个人参栽培群体和1个西洋参(P.quinquefolium L.)群体的遗传分化指数值表明,三路参变异量最大(0.4169),一路参降为0.2565,边条参系选品系59号最低为0.1881,表明选择方式和选择代数的纯化作用十分  相似文献   
104.
In the present study, we evaluated the genetic diversity of Panax notoginseng F H Chen, a domesticated species, and P. stipuleanatus H T Tsai et K M Feng, an endangered wild species in southeastern Yunnan and adjacent areas in Vietnam, using sequences of the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA and amplified fragment length polymorphism (AFLP) markers. Twenty-four accessions from three plantations of P. notoginseng and 51 samples from eight populations of P. stipuleanatus were assayed. A total of 694 bp of partial sequences of 18S, ITS 1, 5.8S, ITS2, and partial sequences of 26S were obtained. No sequence variation was detected within P. notoginseng and nine sites (1.30%) were variable in P. stipuleanatus. Two-thirds of the variable sites were found between Langqiao and other populations. In P. notoginseng, four pairs of AFLP primer combinations generated 312 bands, of which 240 (76.9%) were polymorphic and 60.15% of the polymorphisms were harbored within plantations. Approximately 41.0% and 66.9% of bands were polymorphic in population D7 and 5589, respectively. In P.stipuleanatus, the same four primer combinations produced 346 bands, of which 334 (96.5%) were polymorphic and approximately 62.14% of polymorphisms were maintained within populations. Considerable variations were observed. The percentage of polymorphic bands ranged from 50.2% to 84.9% and the average over populations was 70.9%. Cluster analysis did not show correlation of genetic differentiation with the distinctive leaf morphology of P. stipuleanatus (i.e. one form with bipinnatifid leaflets and the other with undivided leaflets). Because over 40% of genetic variations were maintained among populations and because of the very restricted distribution of P. stipuleanatus, all natural populations of this species should be conserved in situ. Considering that there are variations in P. notoginseng within and among plantations, we suggest establishing a genetic resource conservation garden or reintroducing P. notoginseng into its native habitats in southwestern China. Such reintroduction should be carefully executed after large-scale screening of genetic variation within the species.  相似文献   
105.
Quantitative comparison of seven ginsenosides in wild and cultivated American ginseng revealed that the Rg1/Rd ratio presented a significantly large difference between cultivated and type‐I (one of the defined chemotypes) wild American ginseng, facilitating this ratio as a characteristic marker for differentiating these two groups. Similarly, the ratio (Rg1+Re)/Rd, and the ratio of protopanaxatriol (PPT)‐type ginsenosides to protopanaxadiol (PPD)‐type ginsenosides showed a large difference between these two groups. On the other hand, type‐II wild samples were found to have high Rg1/Rb1 and Rg1/Re ratios and low panaxydol/panaxynol ratio, which is entirely different from Type‐I American ginseng, but is very similar to that of Asian ginseng. This not only suggests that the chemotype should be taken into consideration properly when using these parameters for differentiating American and Asian ginseng, but also indicates that type‐II wild American ginseng may have distinct pharmacological activities and therapeutic effects.  相似文献   
106.
The biotransformation of the major saponins in Panax notoginseng, including the ginsenosides Rg1, Rh1, Rb1, and Re, by endophytes isolated from P. notoginseng was studied. One hundred and thirty‐six endophytes were isolated and screened for their biotransformational abilities. The results showed that five of the tested endophytes were able to transform these saponins. These five strains were identified based on their ITS or 16S rDNA sequences, which revealed that they belonged to the genera Fusarium, Nodulisporium, Brevundimonas, and Bacillus genera. Ten transformed products were isolated and identified, including a new compound 6‐O‐[α‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucopyranosyl]‐20‐Oβ‐D ‐glucopyranosyldammarane‐3,6,12,20,24,25‐hexaol ( 3 ), and nine known compounds, compound K ( 1 ), ginsenoside F2 ( 2 ), vinaginsenoside R13 ( 4 ), vinaginsenoside R22 ( 5 ), pseudo‐ginsenoside RT4 ( 6 ), (20S)‐protopanaxatriol ( 7 ), ginsenoside Rg1 ( 8 ), vinaginsenoside R15 ( 9 ), and (20S)‐3‐Oβ‐D ‐glucopyranosyl‐6‐Oβ‐D ‐glucopyranosylprotopanaxatriol ( 10 ). This is the first study on the biotransformation of chemical components in P. notoginseng by endophytes isolated from the same plant.  相似文献   
107.
目的:探讨三七总皂苷(PNS)对大鼠脑缺血再灌注损伤后大脑皮层细胞的凋亡抑制作用.方法:采用大脑中动脉栓塞再通法建立脑缺血再灌注模型,将大鼠随机分为假手术组、缺血再灌注组和三七总皂苷治疗组;根据再灌注时间不同分为再灌注10h、12 h、24h组,缺血时间为90 min.大鼠脑缺血再灌注10h、12h和24h不同时间点进行神经功能评分,采用原位末端标记法检测神经细胞凋亡情况,同时用免疫组化法检测抑制凋亡蛋白XIAP和促凋亡蛋白Smac阳性细胞数.结果:缺血再灌注组神经细胞凋亡数明显增加,XIAP蛋白的表达呈先高后低的变化(P<0.05),Smac蛋白的表达明显上升(P<0.05);PNS治疗组能明显减少脑皮层组织神经细胞凋亡数(P<0.05),增加XIAP蛋白表达(P<0.05),减少Smac蛋白表达(P<0.05).结论:PNS可能通过促进抑制凋亡蛋白XIAP的表达和抑制促凋亡蛋白Smac的表达,减少脑组织缺血再灌注损伤后的神经细胞凋亡,进而对再灌注后脑组织具有抑制脑细胞凋亡的作用.  相似文献   
108.
通过对药用植物三七总皂苷原粉和超微粉的粉体粒度、电位、显微结构、红外光谱、溶解速度这几项理化性质的研究,判定两种粉体的优劣,为三七总皂苷超微粉的市场推广提供依据。实验结果表明,三七总皂苷原粉经纳米化处理后成为三七总皂苷超微粉,其化学结构没有发生变化,但显微结构从条状的晶体变为由纳米球紧密排列的不规则形态,其粉体平均粒径也从1 122.4 nm缩小到153.4 nm,完成了从微米到纳米的转变,其水溶液也变为稳定的胶体溶液。运用高效液相色谱法,在模拟人体环境的条件下,发现三七总皂苷超微粉比三七总皂苷原粉早1 min完全溶解。说明三七总皂苷超微粉比三七总皂苷原粉颗粒更小,更易溶于水,更易与人体吸收。  相似文献   
109.
To delineate the mosquitocidal regions of the ISRH3 (CryIVB) and ISRH4 (CryIVA) proteins, which are two of the mosquitocidal 130-kDa proteins contained in the crystalline protein bodies (CPBs) of Bacillus thuringiensis var. israelensis (BTI), a deletion analysis of these protein genes has been done. Based on the evidence that each 130-kDa protein had two mosquitocidal regions, N-terminal and C-terminal ones, and these two regions shared a common part in the center of the 130-kDa proteins, deleted genes on this region were constructed. As the protein products which lacked the central region had reduced activities, the central region could be important for the mosquitocidal activity. The mosquitocidal and non-mosquitocidal truncated gene products of 130-kDa protein genes were also applied to a cultured lepidopteran cell line, TN-368. The mosquitocidal proteins caused the swelling and disruption of the cells in spite of the insecticidal specificity of CPBs of BTI, but the non-mosquitocidal proteins did not. Therefore, TN-368 cells were sensitive to the mosquitocidal fragments of 130-kDa proteins of BTI under the assay conditions used.  相似文献   
110.
Qi LW  Wang CZ  Yuan CS 《Phytochemistry》2011,72(8):689-699
Ginseng occupies a prominent position in the list of best-selling natural products in the world. Compared to the long history of use and widespread research on Asian ginseng, the study of American ginseng is relatively limited. In the past decade, some promising advances have been achieved in understanding the chemistry, pharmacology and structure-function relationship of American ginseng. To date, there is no systematic review of American ginseng. In this review, the different structures of the ginsenosides in American ginseng are described, including naturally occurring compounds and those resulting from steaming or biotransformation. Preclinical and clinical studies published in the past decade are also discussed. Highlighted are the chemical and pharmacological diversity and potential structural-activity relationship of ginsenosides. The goal is that this article is a useful reference to chemists and biologists researching American ginseng, and will open the door to agents in drug discovery.  相似文献   
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