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Rhodiola rosea L. (różeniec górski) to bylina należąca do rodziny Crassulaceae, występująca na terenach północnych Azji, górskich regionach Europy oraz w subarktycznych rejonach Ameryki Północnej. Różeniec górski od wieków jest stosowany w tradycyjnej medycynie azjatyckiej. Przypisuje mu się działanie stymulujące ośrodkowy system nerwowy, działanie zwiększające fizyczną i umysłową wydolność organizmu, zmniejszające zmęczenie, a także działanie adapto- genne, kardiochronne, przeciwnowotworowe i przeciwutleniające. Istnieje niewiele badań farmakologicznych czy klinicznych potwierdzających tak szeroki zakres działania wyciągów z Rhodiola rosea. Najbardziej interesującym aspektem działania tej rośliny są jej własności psychostymulujące, które wzbudzają duże nadzieje na wykorzystanie w medycynie lub w do­datkach funkcjonalnych diety. Korzenie różeńca górskiego zawierają bardzo wiele związków biologicznie czynnych, takich jak fenylopropanoidy (rozawiny), związki fenolowe (salidrozyd), monoterpeny, flawonoidy, p-tyrozol i kwasy organiczne. Wyciągi z różeńca mają rozległy za­kres działania fizjologicznego, włącznie ze zmianą poziomu neurotransmiterów, aktywnośa centralnego układu nerwowego i układu krążenia. Psychostymulujące działanie kojarzone jest ze zmianami poziomu dopaminy i serotoniny w mózgu. Własności adaptogenne wiąże się ze zdolnością wpływania na poziom i aktywność niektórych monoamin i peptydów opioidowych, takich jak beta-endorfiny. Aktywność przeciwutleniająca i działanie ochronne na różne tkanki organizmu wyciągów z Rhodiola rosea potwierdzono w licznych pracach naukowych. Biotechnologiczne badania nad różeńcem górskim są prowadzone w wielu krajach (m.in. w Rosji, Finlandii, Niemczech i Polsce). Celem naukowców jest zwiększenie zawartości związków biologicznie czynnych w kulturach tkankowych za pomocą elicytacji czy biotrans- formacji, co jest spowodowane wzrastającym obecnie zainteresowaniem przemysłu farma­ceutycznego, kosmetycznego i spożywczego nowymi, alternatywnymi sposobami otrzymy­wania cennego surowca roślinnego.
Salvia miltiorrhiza (family: Lamiaceae) is well known as Danshen in traditional Chinese medicine. It is used mainly in the treatment of cardiovascular diseases. A number of pharmacological studies have proved its wide spectrum of pharmacological activities: cardiovascular protective effect, antioxidant, anti-inflammatory, neuroprotective, antimicrobial and anticancer. The roots of S. miltiorrhiza contain two main groups of active compounds: phenolic constituents and abietane-type diterpenoids (tanshinones). The studies on S. miltiorrhiza in vitro cultures have been focused on secondary metabolites production for over two decades. Both cultures, undifferentiated and transformed, are able to synthesize the active compounds but their content is low. The elicitation treatment significantly enhances the metabolites content at a level close or much higher than in the intact plants. The induction effect depends on many factors: the kind and dose of the elicitor, the type of the culture and its susceptibility, time and ways of administration, the growth state of tissues etc. The yeast extract and some heavy metal ions effectively induce tanshinones biosynthesis such as cryptotanshinone, whereas methyl jasmonate stimulate mainly phenolic compounds – lithospermic acid B and demonstrated limited effect on diterpenoids accumulation. Nowadays, the much attention has been paid to the biosynthetic pathways and genes including expression profiling and cloning. The recognition of the genes pathways and the transcription factors (including the signal transduction steps level) will be helpful in better understanding of the regulatory mechanism and improvement of the production of the interesting secondary metabolites and eventually appliance in the industry.
Rhodiola Kirilowii (Regel) Maxim. (Crassulaceae) is a traditional medicinal plant used in North Asia and China, especially in the cardiopulmonary disorders in the hypoxic conditions induced by high altitude. The presented results are the part of the investigations carried out in the Branch of Medicinal Plants of the Institute of Natural Fibres and Medicinal Plants in cooperation with the Department of Biology and Pharmaceutical Botany, Medical University in Warsaw on R. Kirilowii plants and tissue cultures. The aim of recent study was to determine the growth dynamics and active compounds production during the cultivation of callus tissues of R. Kirilowii on solid/liquid media. Tissue cultures of R. Kirilowii shown the ability to produce all the active compounds determined in the roots of plants of Polish origin. It is worth emphasizing, that rosavins, according to known literature, were not detected in roots of plants growing in Asia. The best time for collection the tissues from solid medium was fifth or sixth week of the culture – the tissues were growing dynamically and the contents of the main active compounds was high. The material from suspension should be collected in 12–15 days after inoculation. The obtained results will be applied in future investigations on the use of R. Kirilowii extracts in the experimental hypoxia in rats.
Introduction: Despite widespread use of Panax ginseng and Ginkgo biloba, the data on the safety as well as herb-drug interactions are very limited. Therefore, we postulate that P. ginseng and G. biloba may modulate the activity and content of cytochrome P450 isozymes involved in the biotransformation of diverse xenobiotic substances. Objective: The aim of our study was to determine the influence of herbal remedies on the expression level of CYP enzymes and transcriptional factors. Methods: Male Wistar rats were given standardized Panax ginseng (30 mg/kg p.o.) or standardized Ginkgo biloba (200 mg/kg p.o.) for 3 and 10 days. The expression in liver tissue was analyzed by realtime PCR method. Results: Our results showed a decrease of CYP3A1 (homologue to human CYP3A4) mRNA level after P. ginseng extract treatment. The CYP2C6 (homologue to human CYP2C9) expression was also reduced. Additionally, after 10 days of the treatment with P. ginseng an increase of CYP1A1 (homologue to human CYP1A1) and CYP1A2 (homologue to human CYP1A2) expression was observed. Moreover, G. biloba extract also caused an increase of expression level for CYP1A1, CYP2C6, CYP3A1 and CYP3A2. Conclusion: Our findings suggest that herbal extracts can modulate the expression of transcriptional factors and CYP enzymes involved in xenobiotic metabolism and chemical carcinogenesis.
Tussilago farfara L. (family Asteraceae) is a valuable medicinal plant that has been used as a cough suppressant and as an antibacterial and anti-inflammatory drug. Mucopolysac charides, flavonoids, sterols, phenolic acids and pyrrolizidine alkaloids (PAs) are the main active compounds of coltsfoot. Due to hepatotoxic properties of some pyrrolizidine alkaloids, raw materials that contain PAs should be monitored and determined. The aim of present work was to establish nodal cultures of Tussilago farfara and to determine the content of senecionine and senkirkine in plants propagated in in vitro conditions. Eleven clones of coltsfoot derived from Polish natural populations were established. Rhizome buds were used as explants for the initiation of in vitro cultures on MS (Murashige and Skooge) medium. Every six weeks the shots and leaves were collected and dried. The HPLC method was applied for the identification and determination of senecionine and senkirkine. Content of pyrrolizidine alkaloids varied significantly depending on origin (population). An average sum of alkaloids (senecionine and senkirkine) ranged from 1.23 to 10.47 mg/100g d.w. that corresponds to 0.0013–0.011%, respectively.
The main aim of this study was to search the influence of exogenous addition of rosavin precursor: cinnamyl alcohol on the enhancing of rosavins content in callus culture of R. rosea, cultured on solid and liquid media (CCA). This is the first report – according to available literature – which concerns its biotransformation on solid medium conditions. The two strains of R. rosea tissue cultures showed different ability of cinnamyl alcohol glycosides production: both of them produced rosin (with or without supplementation), but the obtained level of rosavin production was notable higher in case of supplementation of the strain induced from axially buds of R. rosea. The exogenous cinnamyl alcohol was added into medium at concentration of 2.5 mM/L or 5 mM/L in the day of the inoculation. The application of 2.5 mM cinnamyl alcohol resulted in the increase of rosin content in the callus started from hypocotyle to very high levels: 1056.183 mg/100 g on solid medium and 776.330 mg/100 g in liquid medium. The content of rosavin showed the same growing tendency, but the final concentration of this phenylopropanoid in the supplemented callus tissue was about 7 times lower as compared to the roots of intact plant (63.603 mg/100 g). Addition of cinnamyl alcohol also enhanced rosarin biosynthesis but only in small amount: to 4.896 mg/100 g on solid medium. Callus tissue obtained from axially buds and treated by cinnamyl alcohol (2.5 mM) produced rosavin in a higher concentration: 92.801 mg/100 g and reached one fifth part of the amount produced by roots. The process of supplementation with cinnamyl alcohol influenced the enhanced biosynthesis of another bioactive substances as well (salidroside, tyrosol, chlorogenic acid). The obtained results confirmed that even on a solid medium the callus tissue can produce the characteristic active substances and the concentration of some of them, mainly rosin and rosavin, can be significantly improved by addition of the precursors to the medium.
The aim of this research was to enhance the content of salidroside by exogenous addition of p-tyrosol in R. rosea tissue cultures. The callus tissue cultured on solid medium (MS with addition of NAA, BAP and adenine chloride) and compact callus agregate (CCA) were used in the experiments. The p-tyrosol was added to medium at a concentration of 5 mM/L (both into liquid and solid medium) and at concentration of 2.5 mM/L (only into liquid medium) in the day of the inoculation. The content of salidroside approximated: 23.15 mg/g (on solid medium) and 43.22 mg/g (CCA) after 7 days of 5 mM/L p-tyrosol application. The yield of salidroside was 3.1% (solid medium) and 4.3% (CCA). The addition of 2.5 mM tyrosol to CCA culture induced the increase of the content of salidroside to 34.73 mg/g and 3.5% yield of salidroside was obtained. The adverse effect was observed in biomass. Salidroside was not released into the medium.
Salvia milthiorrhiza root (Danshen) is one of the oldest and most traditional drug of Chinese origin, mainly used in the treatment of cardiovascular and cerebrovascular diseases. The tanshiniones (diterpenoids) and phenolic acids are the main biological active substances of S. miltiorrhiza. The aim of this study was to determine the optimal conditions for callus cultures and biosynthesis of the biological active compounds. The callus cultures (on solid medium, CC A in shake flask and CC A in bioreactor) were obtained and phytochemical studies on them were carried out. Total amount of phenolic acids determined in callus (solid medium) averaged from 2.58% to 5.72% of dry weight (DW). The callus cultured on solid medium and CC A (in flasks) did not produce tanshiniones. Culture conditions in the bioreactor enabled the biosynthesis of tanshiniones (0.27% of dihydrotanshinione, 0.12% of cryptotanshinone, 0.01% of tanshinione 2A and tanshinione 1). The obtained contents of rosmarinic acid in callus on solid medium and CC A (cultured in shake flasks) are relatively high and comparable to raw material. The callus cultured in bioreactor is eligible for tanshinione production, moreover the accumulation of them is comparable with the intact plants.
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