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21.
Tanaka H Atsumi I Shirota O Sekita S Sakai E Sato M Murata J Murata H Darnaedi D Chen IS 《化学与生物多样性》2011,8(3):476-482
Two new isoflavonoids, eryvarins V and W (1 and 2, resp.), and a new chromen-4-one derivative, eryvarin X (3), along with three known isoflavonoids, 4-6, were isolated from the roots of Erythrina variegata. Their structures were established by spectroscopic analyses. Compound 1 is a rare naturally occurring isoflavanone which possesses a OH group at C(3). Among the new compounds 1-3, 2 exhibited a potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) strains. 相似文献
22.
《Bioscience, biotechnology, and biochemistry》2013,77(9):1469-1473
Synthetic oligonucleotides representing all possible sequences of the N-terminal and internal amino acid sequences of the chymotrypsin inhibitor ECI from Erythrina variegata seeds were used to generate a probe specific for ECI-related sequences by the polymerase chain reaction on the E. variegata genomic DNA. A lambda phage cDNA library constructed from poly(A+) RNA from maturing seeds was screened with the ECI gene thus obtained as a probe and characterized by DNA sequencing. The cloned ECI cDNA comprised 737 nucleotides and one open reading frame that encoded a polypeptide chain of 203 amino acids including a signal peptide composed of 24 amino acids. An expression plasmid was designed for export of the recombinant inhibitor into the periplasm. For this purpose, the cDNA fragment encoding matured ECI was ligated into the NcoI and BamHI sites following the pel B signal sequence in the expression vector pET-22b and expressed in Escherichia coli BL21 (DE3). However, this attempt failed as the recombinant inhibitor caused the formation of inclusion bodies in E. coli cells as a heterologous preprotein (SR-ECI), with the pel B upstream leader. SR-ECI was made soluble and renatured by refolding and reoxidation, and subsequently processed with pronase to give rise to recombinant ECI (R-ECI) that had an extra methionine residue attached to the N-terminal amino acid of ECI. Purified R-ECI inhibited chymotrypsin almost as strongly as authentic ECI. 相似文献
23.
《Bioscience, biotechnology, and biochemistry》2013,77(6):1041-1044
To discover the specificity of Streptomyces β-xylanase toward xylan having glucose stubs, glucoxylan was prepared by the hydrogenation of cotton-seed cake glucuronoxylan. The glucoxylan was hydrolyzed by the β-xylanase of Streptomyces olivaceoviridis E-86, and three kinds of glucoxylo-oligosaccharides were isolated from the hydrolysate by chromatographies on a charcoal column, preparative paper partition, and a Toyopearl HW-40F column. The isolated oligosaccharides had the structures of 23-α-glucopyranosylxylo-triose, 23-α-(4–O-methyl-glucopyranosyl)xylotriose and 24-α-glucopyranosylxylotetraose. From the structure of the above oligosaccharides and the results of our previous studies, we suggest that the specificity of Streptomyces β-xylanase toward glucose stubs is the same as that toward glucuronic acid stubs, but differs considerably from that toward arabinose stubs. 相似文献
24.
Mir Muhammad Nasir Uddin Talha Bin Emran Muhammad Mamunur Rashid Mahib Raju Dash 《Bioinformation》2014,10(10):630-636
Secondary metabolites from plants are a good source for the NSAID drug development. We studied the analgesic activity of
ethanolic extract of Erythrina variegata L. (Fabaceae) followed by molecular docking analysis. The analgesic activity of Erythrina
variegata L. is evaluated by various methods viz., acetic acid-induced writhing test, hot plate and tail immersion test. Subsequently,
molecular docking analysis has been performed to identify compounds having activity against COX-1 and COX-2 enzymes by
using GOLD docking fitness. The result of preliminary phytochemical screening revealed that the extract contains alkaloids and
flavonoids. In analgesic activity tests, the extract at the doses of 50, 100 and 200 mg/kg body weight (b.w.) produced a increase in
pain threshold in a dose dependent manner. In acetic acid induced writhing test, the inhibitory effect was similar to the reference
drug diclofenac sodium. The extract showed 18.89% writhing inhibitory effect at the dose 200 mg/kg b.w., whereas diclofenac
sodium showed 79.42% inhibition of writhing at a dose of 10 mg/kg b.w. The results of tail immersion and hot plate test also
showed potential analgesic activity of the extract which is also comparable to the standard drug morphine (5 mg/kg b.w.). Docking
studies shows that phaseollin of Erythrina variegata L. has the best fitness score against the COX-1 which is 56.64 and 59.63 for COX-
2 enzyme. Phaseollin of Erythrina variegata L. detected with significant fitness score and hydrogen bonding against COX-1 and
COX-2 is reported for further validation. 相似文献
25.
Mark P. Culik David dos Santos Martins José Aires Ventura Valmir Antonio Costa 《Biocontrol Science and Technology》2014,24(8):971-975
The invasive gall wasp Quadrastichus erythrinae, a pest of Erythrina plants, is recorded for the first time in South America in Espírito Santo, Brazil. Research on Q. erythrinae and its potential natural enemies in this region is required to determine the need for classical biological control of this invasive pest. 相似文献
26.
Elder Ant?nio Sousa Paiva 《Annals of botany》2009,104(5):937-944
Background and Aims
The occurrence of nectaries in fruits is restricted to a minority of plant families and consistent reports of their occurrence are not found associated with Fabaceae, mainly showing cellular details. The present study aims to describe the anatomical organization and ultrastructure of the pericarpial nectaries (PNs) in Erythrina speciosa, a bird-pollinated species, discussing functional aspects of these unusual structures.Methods
Samples of floral buds, ovaries of flowers at anthesis and fruits at several developmental stages were fixed and processed by the usual methods for studies using light, and scanning and transmission electron microscopy. Nectar samples collected by filter paper wicks were subjected to chemical analysis using thin-layer chromatography.Key Results
The PNs are distributed in isolation on the exocarp. Each PN is represented by a single hyaline trichome that consists of a basal cell at epidermal level, stalk cell(s) and a small secretory multicellular head. The apical stalk cell shows inner periclinal and anticlinal walls impregnated by lipids and lignin and has dense cytoplasm with a prevalence of mitochondria and endoplasmic reticulum. The secretory cells show voluminous nuclei and dense cytoplasm, which predominantly has dictyosomes, rough endoplasmic reticulum, plastids, mitochondria and free ribosomes. At the secretory stage the periplasmic space is prominent and contains secretion residues. Tests for sugar indicate the presence of non-reducing sugars in the secretory cells. Nectar samples from PNs contained sucrose, glucose and fructose.Conclusions
The secretory stage of these PNs extends until fruit maturation and evidence suggests that the energetic source of nectar production is based on pericarp photosynthesis. Patrolling ants were seen foraging on fruits during all stages of fruit development, which suggests that the PNs mediate a symbiotic relationship between ants and plant, similar to the common role of many extrafloral nectaries. 相似文献27.
A lectin was isolated and characterised from Salvia bogotensis seeds. Removal of the abundant pigments and polysaccharides, which are present in seeds, was an essential step in its purification. Several procedures were assayed and the best suited, including Pectinex treatment, DEAE-cellulose and affinity chromatography, led to a protein being obtained amounting to 18-20mg/100g seeds having high specific agglutination activity (SAA). The lectin specifically agglutinated human Tn erythrocytes and was inhibited by 37mM GalNAc, 0.019mM ovine submaxillary mucin (OSM) or 0.008mM asialo bovine submaxillary mucin (aBSM). Enzyme-linked lectinosorbent assay (ELLSA) revealed strong binding to aOSM and aBSM, corroborating Tn specificity, whereas no binding to fetuin or asialo fetuin was observed. The lectin's monomer MW (38,702Da), amino acid composition, pI, carbohydrate content, deglycosylated form MW, thermal stability and Ca(2+) and Mn(2+) requirements were determined. Evidence of the existence of two glycoforms was obtained. The lectin's specificity and high affinity for the Tn antigen, commonly found in tumour cells, makes this protein a useful tool for immunohistochemical and cellular studies. 相似文献
28.
P. NYGREN 《Plant, cell & environment》1995,18(9):977-988
Above-ground nitrogen fluxes following a complete pruning of the neotropical agroforestry tree Erythrina poeppi-giana (Walpers) O.F. Cook (Leguminosae: Phaseoleae) were studied during pruning intervals of 26 and 23 weeks in the humid tropics of Costa Rica. The experiment included four clones and a half-sib family of the species. The leaf-level N fluxes were modelled as a function of leaf age, and were scaled to the canopy level on the basis of the leaf age distribution. The N content of young leaves increased exponentially, followed by relatively small changes at maturity. Slight net N retranslocation started at the middle of leaf life span, but a major N efflux occurred only a few days before leaf shedding. It was estimated that, depending on the tree source, 29-44& of the total N accumulation in the above-ground biomass occurred during 11 weeks after pruning (WAP), before initiation of nodulation. The nodule biomass peaked at the time leaf shedding started (15–17 WAP). Considerable rapid N efflux from the foliage was observed at this time, suggesting regulation of nodulation by a feedback from the foliage. The implications of the N economy of E. poep-pigiana on its management in agroforestry systems are discussed. 相似文献
29.
Three prenylated flavonoid derivatives; 5,7,4′-trihydroxy-8-(3-methylbut-2-enyl)-6-(2″-hydroxy-3″-methylbut-3″enyl) isoflavone (isoerysenegalensein E), 5,7,2′-trihydroxy-4′-methoxy-5′-(3″-methylbut-2″-enyl) isoflavanone (lysisteisoflavanone), 5, 4′-dihydroxy-6-(3-methylbut-2-enyl)-2″-hydroxyisopropyl dihydrofurano [4″,5″:8,7] isoflavone (isosenegalensin), together with the four known flavonoids abyssinone V-4′-methylether, alpinumisoflavone, wighteone and burttinone were isolated from the stem bark of Erythrina lysistemon Hutch. (Leguminosae). Structures were elucidated by spectroscopic methods. 相似文献
30.