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1.
Konuklugil B Schmidt TJ Alfermann AW 《Zeitschrift für Naturforschung. C, Journal of biosciences》2001,56(11-12):1164-1165
For the first time callus and suspension cultures of Linum mucronatum ssp. annenum were initiated, grown in darkness at 25 degrees C and analyzed for lignans. 6-Methoxypodophyllotoxin was the main lignan besides smaller amounts of podophyllotoxin isolated and identified by chromatographic methods as well as by 1H NMR. 相似文献
2.
Mohagheghzadeh Abdolali Hemmati Shiva Mehregan Iraj Alfermann A. Wilhelm 《Phytochemistry Reviews》2003,2(3):363-369
Aryltetralin lignans (podophyllotoxin type) are the main lignan constituents of species belonging to Linum section Syllinum (Linaceae). Linum persicum, a perennial plant native to Iran closely related to L. album, has not yet been studied. To evaluate the lignan profile, fresh plants of L. persicumwere collected and divided into different parts and analyzed by HPLC. The main aryltetralin lignans found inL. persicumplant parts, callus and cell cultures were podophyllotoxin (PTOX), 6-methoxypodophyllotoxin (MPTOX) and - and -peltatin. Furthermore, the systematic relationship between L. persicum and other Linum species are discussed in the light of morphological and phytochemical aspects.
Abbreviations: MPTOX – 6-methoxypodophyllotoxin; PTOX – podophyllotoxin; DOP – deoxypodophyllotoxin. 相似文献
3.
The production of cytotoxic lignans by plant cell cultures 总被引:10,自引:0,他引:10
Cytotoxic lignans derived from podophyllotoxin are currently used in cancer chemotherapy. Podophyllotoxin for semi-synthetic derivatization is isolated from the rhizomes of Podophyllum plants growing wild, some of which are counted as endangered species. An alternative source for podophyllotoxin or related lignans may in future be cell cultures derived from different plant species, such as Podophyllum spp or Linum spp. These cell cultures were shown to accumulate considerable amounts of podophyllotoxin or 5-methoxypodophyllotoxin. Optimization of the cell cultivation regime might lead to a renewable source of cytotoxic lignans for medicinal uses. This Mini-Review summarizes the attempts to establish plant cell cultures for the production of podophyllotoxin and related lignans and their optimization towards high levels of these target compounds. It also summarizes the results of studies on the biosynthesis of podophyllotoxin and 5-methoxypodophyllotoxin. 相似文献
4.
We analysed chloroplast lipids of Nicotiana tabacum var. John William's Broadleaf, cultivated under an increased PCO(2) of 700 p.p.m. Glycolipids and phospholipids remain constant under these conditions, whereas the carotenoid content undergoes a quantitative change. The saturation degree of fatty acids increases due to an increase in palmitic acid and decreases in hexadecatrienoic acid and linolenic acid. 相似文献
5.
Bayindir U Alfermann AW Fuss E 《The Plant journal : for cell and molecular biology》2008,55(5):810-820
Due to their peculiar stereochemistry and numerous biological activities, lignans are of widespread interest. As only a few biosynthetic steps have been clarified to date, we aimed to further resolve the molecular basis of lignan biosynthesis. To this end, we first established that the biologically active lignan (−)-hinokinin could be isolated from in vitro cultures of Linum corymbulosum. Two hypothetical pathways were outlined for the biosynthesis of (−)-hinokinin. In both pathways, (+)-pinoresinol serves as the primary substrate. In the first pathway, pinoresinol is reduced via lariciresinol to secoisolariciresinol by a pinoresinol–lariciresinol reductase, and methylenedioxy bridges are formed later. In the second pathway, pinoresinol itself is the substrate for formation of the methylenedioxy bridges, resulting in consecutive production of piperitol and sesamin. To determine which of the proposed hypothetical pathways acts in vivo , we first isolated several cDNAs encoding one pinoresinol-lariciresinol reductase ( PLR-Lc1 ), two phenylcoumaran benzylic ether reductases ( PCBER-Lc1 and PCBER-Lc2 ), and two PCBER-like proteins from a cDNA library of L. corymbulosum. PLR-Lc1 was found to be enantiospecific for the conversion of (+)-pinoresinol to (−)-secoisolariciresinol, which can be further converted to give (−)-hinokinin. Hairy root lines with significantly reduced expression levels of the plr-Lc1 gene were established using RNAi technology. Hinokinin accumulation was reduced to non-detectable levels in these lines. Our results strongly indicate that PLR-Lc1 participates in (−)-hinokinin biosynthesis in L. corymbulosum by the first of the two hypothetical pathways via (−)-secoisolariciresinol. 相似文献
6.
Plant cell factories as a source for anti-cancer lignans 总被引:2,自引:0,他引:2
Arroo R.R.J. Alfermann A.W. Medarde M. Petersen M. Pras N. Woolley J.G. 《Phytochemistry Reviews》2002,1(1):27-35
The review places podophyllotoxin, a powerful anti-cancer material used in clinical treatment of small cell cancers, in focus. The economical synthesis of podophyllotoxin is not feasible and demand for this material outstrips supply. At present, Podophyllum hexandrum (Indian May apple) is the commercial source but it grows in an inhospitable region (the Himalayas) where it is collected from wild stands. Furthermore, the plant is now an endangered species. Alternative sources of podophyllotoxin are considered, e.g., the supply of podophyllotoxin and related lignans by establishing plant cell cultures that can be grown in fermentation vessels. Increase of product yields, by variation of medium and culture conditions or by varying the channelling of precursors into side-branches of the biosynthetic pathway by molecular approaches, are discussed. 相似文献
7.
Transformed root cultures of Coluria geoides Ledeb. were established with the use of Agrobacterium rhizogenes LBA 9402. Both normal and transformed root cultures were investigated for their growth and yield of eugenol. Normal roots were grown in B5 medium-supplemented with 0.2 mg l-1 of kinetin and 0.2 mg l-1 of 1-naphthaleneacetic acid (NAA). Hairy roots grew well in hormone-free B5 medium. Both hairy roots and normal roots produced glycosidic bound eugenol. as with the roots of intact plants, eugenol was the main component of the total essential oils obtained from hairy root and normal root cultures. The yield of eugenol from normal roots was 0.1–0.25% of the dry wt. and depended on the development stage of the culture. Yield of eugenol from hairy roots was 0.08–0.1% of the dry wt. NAA modified the hairy root morphology and influenced the yield of eugenol.Abbreviations NAA
1-naphthaleneacetic acid 相似文献
8.
Suspension cultures of Berberis wilsonae produce 4 berberine-type alkaloids: berberine, palmatine, columbamine and jatrorrhizine. In particular the formation of the phenolic alkaloids columbamine and jatrorrhizine and of berberine proves to be dependent on the concentration of dissolved oxygen. With higher aeration rates, berberine and jatrorrhizine yields can be increased considerably. Thus we reached an alkaloid yield of more than 3 g × 1–1 with 50% dissolved oxygen tension in the medium. As far as we know this is one of the best results in fermenting of alkaloid-producing cell cultures.Abbreviations pO2
dissolved oxygen concentration in % saturation (using air)
- HPLC
high-performance liquid chromatography
- vvm
volume air × volume medium–1 × minute–1
- rpm
revolutions per minute
- IAA
indole-3-acetic acid
- 2,4-D
2,4-dichlorophenoxy acetic acid 相似文献
9.
Natural product formation by plant cell biotechnology 总被引:3,自引:0,他引:3
This short review tries to compile some results, which show the importance and the potential of plant cell and tissue cultures for a biotechnological production of natural products. On the other hand, it can not be denied, that a real breakthrough of this technique has not yet been achieved. The problems involved and possible ways to overcome these will be discussed.Dedicated to the memory of Prof. Dr. G. Haberlandt on the occasion of the 50th anniversary of his death 相似文献
10.
Attempts were made to immobilize digitoxin 12-hydroxylase, a membrane-bound, cytochrome P-450-dependent monooxygenase from cell cultures of Digitalis lanata. The optimum procedure was the entrapment of microsomes in 2% alginate by crosslinking the polysaccharide chains with CaCl2. After the immobilization of the enzyme about 70% of its activity was retained. The kinetic data such as the pH optimum and the optimum substrate concentrations were identical for the immobilized enzyme and freely suspended microsomes. Using -methyldigitoxin as a substrate enzyme activity could be observed for more than 20 h. A continuous flow system for immobilized digitoxin 12-hydroxylase is described.Abbreviations -mdg
-methyldigoxin
- -mdt
-methyldigitoxin 相似文献