Aachen, Techn. Hochsch., Diss., 1995.

Milk thistle, Silybum marianum L. Gaertn., is a source of flavonoid taxifolin and flavonolignans - silymarin complex (silybin, silydianin, silycristin and isosilybin). Milk thistle is usually obtained by field cultivation. Alternative way for getting the active components, is the use of in vitro cultures. But the production of secondary metabolites by the in vitro cultures is low in comparison with plant. One of the possibilites how to increase this produciton is the method of elicitation. In this study, ethephon as the elicitor, in the concentrations of 500 µmol/l, 400 µmol/l, 200 µmol/l, 100 µmol/l and 50 µmol/l was used with the aim to increase secondary metabolite production in suspension and callus cultures. The effect of ethephon was compared to its inhibitor (AgNO3, 120 µmol/l). The levels of flavonolignans and taxifolin were measured by the method of HPLC. The samples were taken 24, 48, 72, 96 and 168 hours after the ethephon application and inhibitor treatment. The nutrient medium of suspension culture was also tested for the possibity of secondary metabolites releasing into medium. The highest content of flavonoid taxifolin was found in the suspension culture medium after 48 h treatment with ethephon in conc. of 400 µmol/l. The level of taxifolin was increased by 197-fold to 1,97 mg/100...

Medicinal plant cultures in vitro - XVI The subject of this diploma thesis is the evaluation of secondary metabolites production in Silybum marianum, (L.) Gaertn. cultures in vitro after elicitor treatment. The aim of the study was to find if an abiotic elicitor 5-tert-butyl-N-(4- chlorbenzyl)pyrazine-2-carboxamide increases the flavonolignan production Silybum marianum cultures in vitro. Experiment was carried out in callus and suspension cultures of Silybum marianum using Murashige - Skoog nutrient medium supplemented with 10 mg/l α-naphthylacetic acid. The elicitor was added in the form of solution in three different concentrations (C1 = 3. 292.10-3 mol/l, C2 = 3. 292.10-4 mol/l and C3 = 3. 292.10-5 mol/l) and it was affecting 6, 12, 24, 48, 72 and 168 hours. The content of flavonolignans was determined by HPLC. The maximum flavonolignan production (0. 280 mg.g-1 DW) in callus culture was observed after 24 hours of elicitor application in concentration of C2 = 3. 292.10-4 mol/l, when the highest content of silychristin was detected. The second significant increase in flavonolignan production (0. 271 mg.g-1 DW) in callus culture was noticeable after 12 hours of elicitor treatment in concentration of C3 = 3. 292.10-5 mol/l, when the highest increase in silydianin and silybin B accumulation was found. The...

Genista tinctoria, family Fabaceae, is a potent source of isoflavonoids (genistin, genistein, daidzein, formononetin, biochanin A) with a wide spectrum of potential medical impact. Genista also contains quinolizidin alkaloids (cytisin, anagyrin, lupanin, spartein, etc.), which are toxic. The reason why in vitro cultures are used is an absence of toxic alkaloids production and higher yield of isoflavonoids in comparison with intact plant. For an increase of isoflavonoid production method of elicitation is beeing used. Isoflavonoids are studied for their phytoestrogenic effects, for which they could be used in treatment of postmenopausal symptoms and even in treatment of hormon-dependent tumours. The elicitor ethephon in concentration of 7000 µM, 700 µM and 70 µM was used in this work. The effect of ethephon inhibitor (AgNO3) in concentration of 120 µM was investigated too. Samples were examined after 24, 48, 72, 96 and 168 hours and then analysed by HPLC method. An effect of ethephon and its combination with AgNO3 was observed in callus and suspension cultures. Release of isoflavonoides into culture media was studied too. Daidzein production was the highest of all isoflavonoids in the callus culture after the treatment of ethephon in concentration of 700 µM after 96 hours (45,10 mg/g DW). The most...

The study is aimed to enhance in vitro production of secondary metabolites in Genista tinctoria L. via elicitor treatment. The different levels of elicitor concentration - selenium dioxide were utilized to affect the quantity of isoflavonoids occurred in cultures. Experiment was perfomed in callus and suspension cultures on MS nutrient media supplemented with 10 g l-1 of NAA (α-naphtylacetic acid) as growth regulator. The elicitor was added in the form of solution in concentrations of 9,012.10-3 mol l-1 ; 9,012.10-4 mol l-1 and 9,012.10-5 mol l-1 . It was exposed for 6, 12, 24, 48, 72 and 168 hours. The content of isoflavonoids was determined by HPLC in dry weight (DW) and medium. The most effective production of genistin (6,20 mg. g-1 DW, 8,30 mg. g-1 DW) in callus culture was measured. It was reached in concentrations of 9,012.10-4 mol l-1 and 9,012.10-5 mol l-1 after 168 h elicitor treatment. The second most satisfactory genistin level 5,20 mg g-1 DW was detected after elicitor application in concentration of 9,012.10-4 mol l-1 after 6 h. The content of genistein, daidzein and formononetin in callus culture was low and in the most cases equal zero compared to control samples. The content of biochanin A was equal zero compared to control samples. The most efficient daidzein production (37,10 mg...

The subject of this study is the evaluation of secondary metabolites production in Hypericum perforatum L. cultures in vitro after elicitor treatment. The aim was to find if orthosilicic acid as abiotic elicitor increases the flavonoid and hypericin production in Hypericum perforatum L. cultures in vitro. Experiment was carried out in callus and suspension cultures of H. perforatum using Murashige - Skoog nutrient medium78 supplemented with 10 mg. ml-1 α-naphtylacetic acid as growth regulator. The elicitor was added in the form of solution in 3 different concentrations (C1 = 10.4047∙10-3 mol l-1 , C2 = 10.4047∙10-4 mol l-1 , C3 = 10.4047∙10-5 mol l-1 ), it was affecting 6, 12, 24, 48, 72 and 168 hours. The content of flavonoids and hypericin was determined by HPLC. Secondary metabolites release into nutrient medium was also a part of this study. The increasing flavonoid and hypericin production in callus cultures after elicitor application at any concentrations was not observed. The maximum flavonoid content (0.04 mg g-1 DW) in suspension culture was detected after 72 h of elicitor treatment in concentration of C1 where the maximum hyperoside production was observed. The maximum hypericin production (0.21 mg g-1 DW) in suspension culture was detected after 12 h of elicitor application in...

In vitro cultures of medicinal plants - IXX The subject of this thesis is the evaluation of secondary metabolites production in in vitro cultures of Silybum marianum L. after elicitor treatment. In this study selenium dioxide as elicitor in concentrations of 9,012.10-3 mol/l; 9,012.10-4 mol/l; 9,012.10-5 mol/l was used. The samples were taken after 6, 12, 24, 48, 72 and 168 hours of elicitor treatment. The effect of elicitor was compared with control samples, which were cultured without elicitation. The content of taxifolin and flavonolignans was determined by the method of HPLC. The results showed, that almost all observed metabolites were released into a nutrient medium. Cells of callus and suspension cultures produced only small amounts of taxifolin (0.01 mg/g DW). Taxifolin and silymarin complex releasing into nutrient media was observed as in control and also in the elicitated samples of callus and suspension cultures. Selenium dioxide elicitation caused statistically significant increases in releasing taxifolin and silymarin complex into the nutrient medium. The statistically significant releasing of flavonolignans (2.2 mg/100 ml) to the medium of suspension culture was reached after 72 hours of treatment with selenium dioxide in concentration of c1 (9,012.10-3 mol/l). The statistically...

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19035号 / 農博第2113号 / 新制||農||1031(附属図書館) / 学位論文||H27||N4917(農学部図書室) / 31986 / 京都大学大学院農学研究科応用生命科学専攻 / (主査)教授 宮川 恒, 教授 西田 律夫, 教授 間藤 徹 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Plants are a source of a wide range of secondary substances, which due to their effects find use in many areas of focus. By a method called elicitation, we can achieve their higher and thus more efficient production. This diploma thesis aimed to determine whether the abiotic elicitor 2-(4-chlorophenyl)-N-(5-chloropyridin-2-yl)acetamide can positively affect the production of the flavonoid hyperoside in callus and suspension culture of Hypericum perforatum L. The elicitor was added to the in vitro cultures in three concentrations: C1 = 3,571.10-3 mol/l; C2 = 3,571.10-4 mol/l and C3 = 3,571.10-5 mol/l. A sample was taken at regular intervals after 6, 24, 48, 72 and 168 hours of elicitor treatment. Control samples were taken after 24 and 168 hours. The content of hyperoside produced was subsequently determined using High Performance Liquid Chromatography. Simultaneously, the amount of hyperoside released into the nutrient media of both plant cultures was also monitored. Maximum hyperoside production was recorded in suspension culture after 6 (17,7 µg/g DW) and 48 hours (3,69 µg/g DW) of elicitor treatment with the lowest concentration of C3 (3,571.10-5 mol/l). The content of hyperoside in the first case was 1770 % higher compared to the control sample. There was a significant release of hyperoside...

Univ., Diss.--Würzburg, 1997.