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71.
The growth of Lavandula vera MM cell suspension and the biosynthesis of rosmarinic acid (RA) were followed during its cultivation in Linsmayer–Skoog media, containing different concentrations of ammonium and nitrate ions. The results showed that cultivation in a medium with 0.09g ammonium ions/l (1/4 of standard medium) ensured intensive growth (16g dry biomass/l) and enhanced biosynthesis of RA (15mg/g dry biomass). Cultivation of L. vera MM cell culture in a medium with 1.2-fold concentration of nitrate ions led to accumulation of 11mg RA/g dry biomass which was twice as much as in the standard Linsmayer–Skoog medium.  相似文献   
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Background  

The mechanism by which duplicate genes originate – whether by duplication of a whole genome or of a genomic segment – influences their genetic fates. To study events that trigger duplicate gene persistence after whole genome duplication in vertebrates, we have analyzed molecular evolution and expression of hundreds of persistent duplicate gene pairs in allopolyploid clawed frogs (Xenopus and Silurana). We collected comparative data that allowed us to tease apart the molecular events that occurred soon after duplication from those that occurred later on. We also quantified expression profile divergence of hundreds of paralogs during development and in different tissues.  相似文献   
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Studies were conducted on low molecular metabolites (volatiles and polar compounds) produced by Rosa damascena Mill 1803 cell suspension culture, cultivated under different regimes: as a free suspension (in flasks and in bioreactor) and in a two-phase system (in the presence of Amberlite XAD-4 as a second phase). It was established that the main groups of volatiles were hydrocarbons and free acids and their esters and only traces of terpenoids were found. The main components of polar fraction were free acids, especially amino acids and oxidized acids. Depending on the culture conditions, significant differences were established in the amounts of all compounds under study in biomasses, culture media and adsorbed on the second phase (Amberlite XAD-4).  相似文献   
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Lavandula vera MM cell suspension, grown at 28 degrees C in a 3-l bioreactor, produced rosmarinic acid maximally at 3 g l(-1)) though most biomass (33.2 g dry wt l(-1)) was at 30 degrees C.  相似文献   
76.
The unfavorable safety of existing anticancer medications and the issue of multidrug resistance have fuelled the search for novel plant compounds as potential antineoplastic agents. One of the used approaches for identifying perspective candidates is based on ethnopharmacology. Curcumin is the yellow pigment of curry and has being employed in traditional Indian medicine. Within the EU it has the status of food ingredient (E100) and remains in many food additives. It is isolated from Curcuma longa L. and has been reported as NF-κB inhibitor and apoptosis inducer with antioxidant, cholesterol lowering, anti-inflammatory, anti-parasitic, antibacterial and antitumor potential. Curcumin has been shown to exert a wide spectrum of pleiotropic activities including antitumor effects and protection of the normal bone marrow. It possesses antineoplastic activity in various malignant cell lines in vitro, such as cutaneous T cell lymphoma, acute myeloid leukemia and urinary bladder cancer cells. In lymphoma and leukemia cell lines curcumin induces apoptosis as evidenced by caspase activation, PARP cleavage and oligonucleosomal DNA fragmentation. Expression of the myeloid marker CD13 (aminopeptidase N) is associated with faster apoptosis induction. In addition, curcumin causes concentration-dependent glutathione level increase. Application of curcumin in vivo resulted in protection against cisplatin-induced chromosomal aberrations (anticlastogenic effect). This finding reveals curcumin as preferable partner for combinations with antineoplastic agents in order to potentiate their activity and ameliorate the adverse effects. There is a clear need for new curcumin formulations because of its low bioavailability after oral intake. Cutaneous and intravesical curcumin applications remain a possibility for successful clinical use of curcumin.  相似文献   
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The influence of elicitation on rosmarinic acid biosynthesis by Lavandula vera MM cell suspension culture was investigated using vanadyl sulfate as an abiotic elicitor. It was established that 12 h after treatment with 25 mg/l vanadyl sulfate the rosmarinic acid production was increased up to 3.92 g/l (2.8 times higher compared to the control cultivation). No significant amounts of rosmarinic acid were detected in the culture medium in comparison with its intracellular content. However, it was observed that the extracellular content of rosmarinic acid is 3.3 times higher compared to the control variant (4 h after treatment at elicitor concentration 25 mg/l).  相似文献   
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Enzymatic hydrolysis of cellulose is potentially an attractive method for converting cellulose into glucose which can then be used as a chemical feed or as a growth substrate for a number of microorganisms to produce microbial products. An enzymatic hydrolysis of wheat straw with cellulase preparation “Trichocease” was made. The wheat straw used was pretreated mechanically and with NaOH. A procedure of pretreatment was investigated in 26 variants. The dynamics of enzymatic hydrolysis was studied. An assay of this dynamics based on the amount of reducing sugars formed during the cellulase reaction and depending upon enzyme and substrate concentration and time of action was carried out.  相似文献   
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