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1.
The structure of the yellow pigment found in salted radish roots was studied. It was found that 1-(2-thioxopyrrolidin-3-yl)-1,2,3,4-tetrahydro-β-carboline-3- carboxylic acid (TPCC) was unstable under neutral pH, and was easily converted into the yellow pigment. The yellow pigment was isolated and identified as 2-[3-(2-thioxopyrrolidin-3-ylidene)methyl]-tryptophan (TPMT) by IR, MS, 1H-, and 13C-NMR spectroscopy. In addition, we proved that this compound was the main yellow pigment in salted radish roots. This compound induced no mutagenicity in Salmonella typhimurium TA98 and TA100, either with or without prior activation.  相似文献   

2.
The structure of the yellow pigment found in salted radish roots was studied. It was found that 1-(2-thioxopyrrolidin-3-yl)-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid (TPCC) was unstable under neutral pH, and was easily converted into the yellow pigment. The yellow pigment was isolated and identified as 2-[3-(2-thioxopyrrolidin-3-ylidene)methyl]-tryptophan (TPMT) by IR, MS, 1H-, and 13C-NMR spectroscopy. In addition, we proved that this compound was the main yellow pigment in salted radish roots. This compound induced no mutagenicity in Salmonella typhimurium TA98 and TA100, either with or without prior activation.  相似文献   

3.
The photostability of (E)-2-[3-(2-thioxopyrrolidin-3-ylidene)methyl]-tryptophan ((E)-TPMT), the main yellow pigment in salted radish, was studied. First we analyzed the photoproduct generated from (E)-TPMT under longwave UV irradiation. On the basis of NMR spectroscopy, the photoproduct was identified as Z-configurated TPMT, and isomerization from the Z- to the E-form was reversibly induced by Vis-light irradiation. The optimum wavelength for isomerization from the E- to the Z-form was 360-380 nm, and that for isomerization from the Z- to the E-form was 440-460 nm. The E/Z-ratios in the photostationary state under UV- and Vis-light irradiation conditions were approximately 0.95:1 and 26:1 respectively. The (Z)-isomer was more sensitive to light irradiation than the (E)-isomer in the quantum yield measurement. Yellowing was dependent on the ratio of the (Z)-isomer, because the b(*) and chroma value rose with increases in the (Z)-isomer by the colorimeters. Hence, it is possible that the formation of the (Z)-isomer contribute to the yellow color of takuan-zuke during long salting and fermentation.  相似文献   

4.
In the present study, we have reported synthesis and biological evaluation of a series of fifteen 1-(thiophen-2-yl)-9H-pyrido[3,4-b]indole derivatives against both promastigotes and amastigotes of Leishmania parasites responsible for visceral (L. donovani) and cutaneous (L. amazonensis) leishmaniasis. Among these reported analogues, compounds 7b, 7c, 7f, 7g, 7i, 7j, 7m, 7o displayed potent activity (15.55, 7.70, 7.00, 3.80, 14.10, 9.25, 3.10, 4.85 μM, respectively) against L. donovani promastigotes than standard drugs miltefosine (15.70 μM) and pentamidine (32.70 μM) with good selectivity index. In further, in-vitro evaluation against amastigote forms, two compounds 7g (8.80 μM) and 7i (7.50 μM) showed significant inhibition of L. donovani amastigotes. Standard drug amphotericin B is also used as control to compare inhibition potency of compounds against both promastigote (0.24 μM) and amastigote (0.05 μM) forms.  相似文献   

5.
Radish, Raphanus satvius, is a very important commercial crop in the world, especially in East Asian countries. In this study, radish microsatellite markers have been developed for the first time from expressed sequence tags (ESTs). A total of 8 primer pairs were able to produce clear amplifications, respectively, which gave 2–5 polymorphic loci between 43 cultivars of Japanese radish. Observed and expected heterozygosity ranged from 0 to 0.4186, and from 0.1779 to 0.6205, respectively. Polymorphic information content ranged from 0.171 to 0.575. The eight simple sequence repeats were also polymorphic when tested by wild radish (Raphanus raphanistrum). Deviation from Hardy–Weinberg equilibrium was analysed in three populations, and no linkage disequilibrium was observed. It is anticipated that these newly developed microsatellite markers can advance further genomic analyses. This accomplishment may in turn accelerate and simplify radish breeding programs.  相似文献   

6.
Antibiofilm polymers have the ability to inhibit bacterial biofilm formation, which is known to occur ubiquitously in the environment and pose risks of infection. In this study, production of P(3HB-co-4HB) copolymer and antimicrobial yellow pigment from Cupriavidus sp. USMAHM13 are enhanced through medium optimization. Before the improvement of yellow pigment production, screening for the best additional supplement was performed resulting in high-yield yellow pigmentation using yeast extract with optimum concentration of 2?g/L. Effects of different concentrations of 1,4-butanediol, ammonium acetate, and yeast extract were studied using central composite design. Under optimal conditions, 53?wt% of polyhydroxyalkanoate (PHA) content, 0.35?g/L of pigment concentration, and 5.87?g/L of residual biomass were achieved at 0.56?wt% C of 1,4-butanediol, 1.14?g/L of ammonium acetate, and 2?g/L of yeast extract. Antibiofilm tests revealed that the yellow pigment coated on P(3HB-co-4HB) copolymer had significant effect on the inhibition of bacteria proliferation and colonization from 6?hr onward reaching 100% inhibition by 12?hr, hence effectively inhibiting the biofilm formation.  相似文献   

7.
Abstract The roots of pea (Pisum sativum L. ev. Feltham First) seedlings contained haemagglutinating activity and a protein which reacted with antibodies directed against pea seed lectin. This protein was shown to be present on the surface of root hairs and in the root cortical cells by immunofluorescence. Lectin (haemagglutinin) was purified from pea seedling roots by both immunoaffinity chromatography and affinity chromatography on Sephadex G-100. The pea root lectin was similar to the seed lectin when analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis, and was antigenically identical: however, the isoelectric focussing band patterns of the proteins differed. The sugar specificity of the root lectin differed from that of the seed lectin, and the haemagglutinating activity of the root lectin was less than the seed lectin. These results are discussed with reference to the hypothesis that lectins mediate in the symbiotic association of legume and Rhizobium through their carbohydrate-binding properties.  相似文献   

8.
The purpose of the present study was to evaluate the in vivo efficacy of two cinnamic acid synthetic derivatives (allyl 3-[4-hydroxyphenyl]propanoate; HPP304, 1-naphthyl-methyl 3-[4-hydroxyphenyl]propanoate; HPP305) in high-cholesterol fed rats and compare their actions to that of cinnamic acid. Cinnamic acid and its synthetic derivatives were supplemented with a high-cholesterol diet for 42 days at a dose of 0.135 mmol/100 g of diet. The supplementation of HPP304 and HPP305 significantly lowered cholesterol and triglyceride levels in the plasma and liver with a simultaneous increase in the HDL-cholesterol concentration, whereas cinnamic acid only lowered the plasma cholesterol concentration. Cinnamic acid lowered hepatic HMG-CoA reductase activity in high-cholesterol fed rats, however, its synthetic derivatives (HPP304 and HPP305) did not affect HMG-CoA reductase activity compared to the control group. Instead, the HPP304 and HPP305 supplements significantly lowered hepatic acyl coenzyme A:cholesterol acyltransferase activity and increased the fecal bile acid. The SOD activity of the erythrocytes and liver was not different between the groups, however, the activities of CAT and GSH-Px, and the level of GSH in the erythrocytes were significantly higher in the HPP304 and HPP305 groups than in the control group. On the other hand, the activities of CAT and GSH-Px, and the level of malondialdehyde in the liver were significantly lower in the HPP304 and HPP305 groups. The antioxidant activities of these cinnamic acid synthetic derivatives were similar to the cinnamic acid in the high-cholesterol fed rats. In addition, HPP304 and HPP305 lowered amniotransferase activity in the plasma. These results suggest that two cinnamic acid synthetic derivatives (HPP304 and HPP305) exert lipid-lowering action and antioxidant properties without hepatotoxicity in high-cholesterol fed rats.  相似文献   

9.
The recent literature on hemozoin/β-hematin formation is reviewed, with an emphasis on the mechanism of its formation. Recent findings from unrelated organisms that produce hemozoin, namely the malaria parasite Plasmodium falciparum, the worm Schistosoma mansoni and the kissing bug Rhodnius prolixus all of which consume human hemoglobin show that the formation of this crystalline substance occurs within or at the surface of lipids. Biomimetic experimental models of the lipid–water interface as well as computational studies indicate that these lipid environments are probably extraordinarily efficient at producing hemozoin. A rethink is now needed, with a new emphasis on Fe(III)PPIX in non-aqueous environments that mimic lipids and indeed within the lipid environment itself. These findings are explored and discussed in the context of earlier studies on β-hematin formation.  相似文献   

10.
The direct C-glycosylation of methylphloroacetophenone 8 with d-glucose gave C-beta-d-glucopyranosylmethylphloroacetophenone (7) in 65% yield, which, on oxidation in the presence of small amount of pyridine under an oxygen atmosphere afforded the quinone 9, oxidized at the methylated position of the benzene ring as a pair of diastereomers in 27% yield. A detailed NMR analysis and a comparison of the UV-vis and CD spectra of their acetates indicated that the structure and stereochemistry of 9 was (1R,1'S,2R,3S,3aS,5R and 1R,1'S,2R,3S,3aS,5S)-7-acetyl-2-(1',2'-dihydroxyethyl)-5-methyl-3,5,6-trihydroxy-8-oxofuro[3,2-d]benzo[b]furan.  相似文献   

11.
The levels of indol-3yl-acetic acid and gibberellins were determined in shoots and storage roots of radish (Raphanus sativus L.) at various times during the vegetative growth cycle of control plants and plants in which the root to shoot ratio was modified by daminozide treatment. In control plants the onset of storage organ growth was preceded by a change in the hormone root to shoot ratio to favour the root. There was a general reduction in hormone levels in daminozide-treated plants but the pattern of their distribution in roots and shoots was very similar to that in control plants. Thus the effects of daminozide on increased storage root growth cannot be explained in terms of altered root to shoot hormone ratios.  相似文献   

12.
Abstract Calmodulin (Cam), the heat-stable, ubiquitous, Ca2+-dependent regulator protein, has been purified to apparent homogeneity from germinating radish seeds (Raphanus sativus). The characteristics of radish Cam-molecular weight, absorption spectrum, Ca2+-dependent activation of brain phosphodiesterase (PDE)-are very similar to those described for Cam from other plant materials. Radish Cam, like other plant Cam, shows some differences to Cam of calf brain. The total amount of Cam in radish embryos at 24 h of germination is ca. 37 μg g−1 fresh weight. Approximately 95% of the total amount of Cam is present in the soluble fraction (supernatant at 100,000 g). The level in the embryo axis strongly increases in the first 24 h of germination (+540%); this increase is strongly reduced when the germination is inhibited by abscisic acid (ABA). In the presence of Ca2+, no ‘free’ Cam (i.e. not bound to other structures) is present in the soluble fraction, suggesting that, during early germination, Cam level is a limiting factor for the activities of Ca2+ -Cam-dependent systems. These studies suggest that Cam plays an important role in the early phases of seed germination. An inhibitor of the Ca2+-Cam-dependent phosphodiesterase is present in the soluble fraction from radish embryos; this substance decreases during germination. A possible role of this inhibitor during the early germination phases is hypothesized.  相似文献   

13.
Groot  Edwin P.  Sweeney  Eileen J.  Rost  Thomas L. 《Plant and Soil》2003,248(1-2):85-96
Vines have different climbing strategies; one type, called clinging vines, has developed a specialized structure, the adhesive pad that secretes a sticky substance that adheres to almost any substrate. In this study on the climbing fig, Ficus pumila L., we report on the developmental anatomy of clusters of adventitious roots that become transformed into this unique structure. Clustered adventitious roots in F. pumila are initiated in pairs on either side of a vascular bundle at the 2nd to 3rd internodes of young stems. After emergence through the cortex and epidermis, root hairs form, which secrete a substance that stains positively for polysaccharide and protein. The adventitious roots and root hairs stick together forming the adhesive pad. Pads stick to almost any substrate. If the adventitious roots do not touch a substrate they usually dry up, if they touch moist soil they tend to branch and change to a terrestrial form. We discuss experiments on the shoot developmental behavior leading to adhesive pad formation and the possible roles of auxin.  相似文献   

14.
Summary We used a system with a mobilized Stalker transposable element, sometimes in combination with P-M hybrid dysgenesis, in the search for new mutations interfering with the y 2 mutation induced by mdg4 (gypsy) insertion into the yellow locus. A novel gene, modifier of mdg4, was detected in chromosome 3. The mutation mod(mdg4) either enhanced or suppressed phenotypic changes in different mutations induced by mdg4 insertions. Thus, mod(mdg4) seems to be involved in the control of mdg4 expression. Six other loci designated as enhancers of yellow were also detected. The e(y) n (with n from 1–6) mutations enhanced the expression of several y mutations induced by different insertions into the yellow locus. The major change is a damage of bristle and hair pigmentation which is not suppressed by su(Hw) mutations. On the other hand, e(y) n alleles do not interact with mdg4 induced mutations in other loci. All e(y) n genes are located in different regions of the X chromosome. One may speculate that e(y) n genes are involved in trans-regulation of the yellow locus and possibly of some other loci.  相似文献   

15.
Six polymorphic microsatellite markers were isolated and characterized using an enriched library technique in the large yellow croaker (Pseudosciaena crocea Richardson, 1864), a commercially important marine fish in China. They showed PIC (polymorphism information content) ranging from 0.064 to 0.885 (average of 0.580) and allele numbers ranging from two to 13 (average of 7.5), which were useful for the studies on population genetics and selective breeding of the large yellow croaker.  相似文献   

16.
17.
We report here evidence of the role that the isoform of the eukaryotic translation initiation factor 4G (eIF(iso)4G) plays in naturally occurring resistance in plant/virus interactions. A genetic and physical mapping approach was developed to isolate the Rymv1 locus controlling the high recessive resistance to Rice yellow mottle virus (RYMV) in the rice (Oryza sativa) variety Gigante. The locus was mapped to a 160-kb interval containing a gene from the eIF(iso)4G family. The stable transformation of a resistant line with the cDNA of this gene, derived from a susceptible variety, resulted in the loss of resistance in transgenic plants. The allelic variability of this gene was analysed in three resistant and 17 susceptible varieties from different cultivated rice species or subspecies. Compared with susceptible varieties, resistant varieties present specific alleles, characterized by either amino acid substitutions or short amino-acid deletions in the middle domain of the protein. The structure of this domain was modelled and showed that the substitutions were clustered on a small surface patch. This suggests that this domain may be involved in an interaction with the virus.  相似文献   

18.
AIM: To investigate the immunoprotection of three recombinant proteins derived from the Vibrio harveyi outer membrane proteins (OMPs) OmpK, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and their fusion OmpK-GAPDH as vaccine candidates from vibriosis of large yellow croaker (Pseudosciaena crocea). METHODS: The ompK gene, of which the leader sequence was omitted, was fused with the gapdh gene. Three recombinant proteins r-OmpK, r-GAPDH and r-OmpK-GAPDH were expressed and purified. Western blots were carried out to detect the specificity of the antibodies raised against the recombinant proteins; Fish were immunized with recombinant proteins and challenged by native V. harveyi. The immunoresponse to the recombinant proteins were determined by ELISA and phagocytic activity assay. CONCLUSIONS: The fusion protein r-OmpK-GAPDH can afford greater protection against the wild V. harveyi than r-OmpK or r-GAPDH alone or their mixture in humoral and cellular immunity, indicating that OmpK and GAPDH could produce a synergistic immunoprotection against vibriosis of large yellow croaker (Pseudosciaena crocea) when fused into OmpK-GAPDH with a linker. SIGNIFICANCE AND IMPACT OF THE STUDY: It has been realized that a multi-component OMP antigen can induce a higher frequency of immune effectors than a single OMP. The results presented here bring forth a good suggestion for the subunit vaccine design based on the OMPs of gram-negative pathogens.  相似文献   

19.
Patterns of translocation of recently-assimilated phosphorus (P) exported from'young' source roots (located 3–4 nodes from the stolon apex) and 'old' source roots (located near the base of the stolon) on the primary stolon of clonal plants of the forage legume white clover ( Trifolium repens L.) were determined using 32P. Plants of a small-leaved genotype and of a large-leaved genotype were grown in sand culture at two notionally limiting or near-limiting rates of P supply and one non-limiting rate of supply. The small-leaved genotype showed little response in growth rate to the full range of P treatments whereas growth of the large-leaved genotype at the non-limiting rate of P supply was 2. 4 times greater than at the two low rates of P supply. Source roots of both genotypes exported only 26–30% of the P they acquired to the shoot within 24 h when P supply was limited whereas at the high-P rate 54% of recently-assimilated P was exported. Patterns of translocation of exported P to specific sinks differed little between the genotypes and the P treatments; branches were the main sink, accounting for nearly 80% of the estimated amounts of P (μg day−1) exported from young and old roots combined. Translocation patterns from individual roots were determined largely by the modular structure of plants and by the location of the root relative to the major sinks, and were therefore consistent with the same source-sink principles which govern carbohydrate translocation in clonally-growing species. There were strong suggestions that storage of P in stolons and roots played a much greater role in the growth of the small-leaved plants than of the large-leaved plants.  相似文献   

20.
* The incidence of species that develop specialised 'dauciform' lateral roots, which are hypothesised to be important for phosphorus (P) acquisition, is uncertain. We investigated their occurrence in Australian reed, rush and sedge species, grown at low P concentration in nutrient solution, and studied the response of Schoenus unispiculatus (Cyperaceae) to a range of P concentrations. * We assessed the fraction of root biomass invested in dauciform roots, their respiration and net P-uptake rate, and the P status of roots and leaves. * Dauciform-root development occurred only in particular genera of Cyperaceae when grown at low P supply. Increased P supply was associated with increased growth of S. unispiculatus and increased leaf [P]. Dauciform-root growth was reduced by increased P supply, and reduced P uptake co-occurred with the complete suppression of dauciform roots. * The P-induced suppression of dauciform roots in Cyperaceae is similar to that observed for proteoid roots in members of Proteaceae and Lupinus albus. The response of dauciform roots to altered P supply and their absence from root systems of some sedge species are discussed in terms of managed and natural systems.  相似文献   

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