1000 resultados para flavanone 3-hydroxyase
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Saussurea medusa Maxim3-cDNA 1. cDNA4106pfu/ml1011 pfu/ml98%PCR0.5kb3kb1kb62%chsdfrMybSmPPCR 2. RT-PCRSmchiTD-PCRcDNASmchi cDNA831bp232cDNASmchi DNASmchiSmchi cDNAchiORF84%79.3%Smchi mRNASmCHIChalconeCHI7-8N115M115CHISmchiSmchi50%670%85.1%SmchiSmCHICHICHI 3. Smchi3-Smf3hcDNA1334bp343aacDNASmf3h DNA1630bp43Smf3h mRNA SmF3H2OG-FeII_OxyH6H45%F3H40%SmF3HF3HH6HSmF3HF3HSmf3hSmf3hf3hh6h 4. SmchicDNASmPcDNA969bp256 aacDNASmPDNASmPSmPcDNA mRNAA+T63%A-TSmPR2R3-MybN-Myb DNA-binding DomainMyb1A5JOsMYBThMYB71.3%70.8%;C-NtMYBVlMYBS170S206SmP51%0.5-6SmPSmP92%-100% 5. Erich Grotewold EST50SmANSSmALDHSmANSPCR50SmANScDNA1229bp356aaSmANScDNAANSORF80%mRNA ;ANS82.9%SmANS2OG-FeII_Oxy2OG-FeII_OxyANS94%---711-2OG-FeII_OxyHis84His235His291Asp237 6. ESTSmALDHPCR50SmALDHcDNA 1664bp491aaSmALDHcDNA3/-UTRA+T80%5/-UTRA+TG+C50%ORF52%mRNA5/-UTRSmALDHcDNAORF64.03%63.89%63.72%54.9%54.3%54.0%SmALDHAldedh 1OF7-H---1015-ALDHSmALDH
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Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)
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Das folhas de Deguelia utilis foram isolados cinco flavonoides: 5,3'-di-hidrxi-4'-metxi2'',2''-dimetilcromeno-(5'',6'':6,7)-di-hidroflavonol (1), 5,3'-di-hidrxi-7,4'-dimetxi-6,8dimetilalil-di-hidroflavonol (2), 5,3'-di-hidrxi-4'-metxi-8-prenil-2'',2''-dimetilcromeno(5'',6'':6,7)-flavanona (3), 5,3'-di-hidrxi-7,4'-dimetxi-6,8-dimetilalil-flavanona (4), 3,5,3'-tri-hidrxi-7,4'-dimetxi-6,8-dimetilalil-flavanol (5), juntamente com os estilbenos: 4-metoxilonchocarpeno (6) e lonchocarpeno (7). Suas estruturas qumicas foram elucidadas com base nos seus dados de NMR (ressonncia magntica nuclear) e HRESITOF-MS (espectrometria de massas de alta resoluo por tempo de vo, com ionizao por eletrospray). Alm disso, a fim de investigar o potencial efeito citoprotetor desses flavonoides, foi utilizada uma frao eluda com hexano:AcOEt contendo os sete flavonoides, em um modelo in vitro de neurodegenerao, utilizando culturas primrias do hipocampo de ratos neonatal (PND2-P3) expostos rotenona, um inibidor mitocondrial do complexo I. Houve uma reduo significativa da viabilidade celular (19,4 1,6%), quando as culturas foram expostas rotenona 30 nmol L<sup>-1</sup> por 72 h. A exposio concomitante das culturas a FR3 (5 g mL<sup>-1</sup>) e rotenona 30 nmol L<sup>-1</sup> resultou em valores de viabilidade celular semelhante ao grupo controle (99,6 4,8%), sugerindo um efeito citoprotetor para essa frao.
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A collection of 8,000 Arabidopsis thaliana plants carrying 48,000 insertions of the maize transposable element En-1 has been generated. This population was used for reverse genetic analyses to identify insertions in individual gene loci. By using a PCR-based screening protocol, insertions were found in 55 genes. En-1 showed no preference for transcribed or untranscribed regions nor for a particular orientation relative to the gene of interest. In several cases, En-1 was inserted within a few kilobases upstream or downstream of the gene. En-1 was mobilized from such positions into the respective gene to cause gene disruption. Knock-out alleles of genes involved in flavonoid biosynthesis were generated. One mutant line contained an En-1 insertion in the flavonol synthase gene (FLS) and showed drastically reduced levels of kaempferol. Allelism tests with other lines containing En-1 insertions in the flavanone 3-hydroxylase gene (F3H) demonstrated that TRANSPARENT TESTA 6 (TT6) encodes flavanone 3-hydroxylase. The f3h and fls null mutants complete the set of A. thaliana lines defective in early steps of the flavonoid pathway. These experiments demonstrate the efficiency of the screening method and gene disruption strategy used for assigning functions to genes defined only by sequence.
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Sorghum (Sorghum bicolor L. Moench) accumulates the anthocyanin cyanidin 3-dimalonyl glucoside in etiolated mesocotyls in response to light. Inoculation with the nonpathogenic fungus Cochliobolus heterostrophus drastically reduced the light-induced accumulation of anthocyanin by repressing the transcription of the anthocyanin biosynthesis genes encoding flavanone 3-hydroxylase, dihydroflavonol 4-reductase, and anthocyanidin synthase. In contrast to these repression effects, fungal inoculation resulted in the synthesis of the four known 3-deoxyanthocyanidin phytoalexins and a corresponding activation of genes encoding the key branch-point enzymes in the phenylpropanoid pathway, phenylalanine ammonia-lyase and chalcone synthase. In addition, a gene encoding the pathogenesis-related protein PR-10 was strongly induced in response to inoculation. The accumulation of phytoalexins leveled off by 48 h after inoculation and was accompanied by a more rapid increase in the rate of anthocyanin accumulation. The results suggest that the plant represses less essential metabolic activities such as anthocyanin synthesis as a means of compensating for the immediate biochemical and physiological needs for the defense response.
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Activation of anion channels by blue light begins within seconds of irradiation in seedlings and is related to the ensuing growth inhibition. 5-Nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) is a potent, selective, and reversible blocker of these anion channels in Arabidopsis thaliana. Here we show that 20 m NPPB blocked 72% of the blue-light-induced accumulation of anthocyanin pigments in seedlings. Feeding biosynthetic intermediates to wild-type and tt5 seedlings provided evidence that NPPB prevented blue light from up-regulating one or more steps between and including phenylalanine ammonia lyase and chalcone isomerase. NPPB was found to have no significant effect on the blue-light-induced increase in transcript levels of PAL1, CHS, CHI, or DFR, which are genes that encode anthocyanin-biosynthetic enzymes. Immunoblots revealed that NPPB also did not inhibit the accumulation of the chalcone synthase, chalcone isomerase, or flavanone-3-hydroxylase proteins. This is in contrast to the reduced anthocyanin accumulation displayed by a mutant lacking the HY4 blue-light receptor, as hy4 displayed reduced expression of the above enzymes. Taken together, the data indicate that blue light acting through HY4 leads to an increase in the amount of biosynthetic enzymes, but blue light must also act through a separate, anion-channel-dependent system to create a fully functional biosynthetic pathway.
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A series of novel dispiroheterocyclic systems have been synthesized by the cycloaddition of a new azomethine ylide generated by the decarboxylative route from tetrahydroisoquinoline-3-carboxylic acid and isatin with various dipolarophiles containing exocyclic double bond such as 3-arylidene-4-chromanone, 3-arylidene-4-flavanone and 2-arylidenetetrahydro-1-naphthalenone in moderate to good yield. The regio and stereochemistry of the title compounds was established by single crystal X-ray structure and spectroscopic techniques. (C) 2002 Elsevier Science Ltd. All rights reserved.
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Citrus flavonoids have been investigated for their biological activity, with both anti-inflammatory and -carcinogenic effects being reported. However, little information is known on the bioavailability of these compounds in vivo. The objectives of this study were to determine the tissue distribution of naringenin after gastric gavage of [H-3]-naringenin to rats. Unlabelled naringenin was also used to quantify the levels of naringenin and its major metabolites in tissues and eliminated in the urine and faeces. Significant radioactivity was detected in the plasma as well as all tissues examined 2 h post-gavage. After 18 h, higher levels of radioactivity were retained in plasma and tissues (55% of the administered radioactivity). Investigation of the nature of metabolites, using unlabelled naringenin, revealed that the glucuronides were the major components in plasma, tissues and urine, in addition to the colonic metabolite 3-(4- hydroxyphenyl) propionic acid, detected in the urine. The aglycone was the form extensively retained in tissues after 18 h post-gavage. Total identified metabolites detected after 18 h in most tissues were only 1-5% of the levels detected after 2 h. However, the brain, lungs and heart retained 27, 20 and 11%, respectively, relative to the total metabolites detected at 2 h. While radioactive detection suggests increased levels of breakdown products of naringenin after 18 h versus 2 h, the products identified using unlabelled naringenin are not consistent with this, suggesting that a predominant proportion of the naringenin breakdown products at 18 h are retained as smaller decomposition molecules which cannot yet be identified.
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Background: Research indicates that chronic consumption of flavonoids is associated with cognitive benefits in adults with mild cognitive impairment and neurodegenerative disease, although, there has been no such studies in healthy older adults. Furthermore, the effects of commonly consumed orange juice flavanones on cognitive function remain unexplored. Objective: To investigate whether eight weeks of daily flavanone-rich orange juice consumption was beneficial for cognitive function in healthy older adults. Design: High flavanone (HF: 305mg) 100% orange juice and equicaloric low flavanone (LF: 37mg) orange flavored cordial (500ml) were consumed daily for eight weeks by thirty seven healthy older adults (mean age 67 years) according to a crossover, double blind, randomized design separated by a four week washout. Cognitive function, mood and blood pressure were assessed at baseline and follow up with standardized validated tests. Results: Global cognitive function was significantly better following eight week consumption of flavanone-rich juice relative to eight week consumption of the low flavanone control. No significant effects on mood or blood pressure were observed. Conclusions: Chronic daily consumption of flavanone-rich 100% orange juice over eight weeks is beneficial for cognitive function in healthy older adults. The potential for flavanone-rich foods and drinks to attenuate cognitive decline in ageing and the mechanisms which underlie these effects should be investigated.
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Fractionation of the methanol extract of the leaves of Oricia renieri and Oricia suaveolens (Rutaceae) led to the isolation of 13 compounds including the hitherto unknown furoquinoline alkaloid named 6,7-methylenedioxy-5-hydroxy-8-methoxydictamnine (1) and a flavanone glycoside named 5-hydroxy-40-methoxy-7-O-[a-Lrhamnopyranosyl(1000500)-b-D-apiofuranosyl]-flavanoside (2), together with 11 known compounds (313). The structures of the compounds were determined by comprehensive analyses of their 1D and 2D NMR, mass spectral data and comparison. All compounds isolated were examined for their activity against human carcinoma cell lines. The alkaloids 1, 5, 12, 13 and the phenolic 2, 8, 11 tested compounds exhibited non-selective moderate cytotoxic activity with IC50 8.715.9mM whereas compounds 3, 4, 6, 7, 9 and 10 showed low activity.
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Fundao de Amparo Pesquisa do Estado de So Paulo (FAPESP)
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A low temperature synthesis method based on the decomposition of urea at 90C in water has been developed to synthesise fraipontite. This material is characterised by a basal reflection 001 at 7.44 . The trioctahedral nature of the fraipontite is shown by the presence of a 06l band around 1.54 , while a minor band around 1.51 indicates some cation ordering between Zn and Al resulting in Al-rich areas with a more dioctahedral nature. TEM and IR indicate that no separate kaolinite phase is present. An increase in the Al content however, did result in the formation of some SiO2 in the form of quartz. Minor impurities of carbonate salts were observed during the synthesis caused by to the formation of CO32- during the decomposition of urea.