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1.
A study was made of the changes in the content of essential oil and its components (farnesene, (-)-α-bisabolol, (-)-α-bisabololoxide
A, (-)-α-bisabololoxide B and spathulenol, α-bisabolonoxide A, chamazulene, cis en-in-dicycloether) and of the number of secretory
canals in the receptacles during the beginning of flowering, full flowering and the termination of flowering of camomile anthodia.
The total content of the essential oil was highest during the beginning of flowering and lowest during its termination. The
proportion of the individual sesquiterpenes in the essential oil underwent changes mostly during the beginning and termination
of flowering. The number of secretory canals in the basal and middle anthodial parts increased during the beginning of flowering
and the full flowering. 相似文献
2.
C. T. Miyamoto J. Rocha De Sant’anna C. C. Da Silva Franco M. M. Cunico O. G. Miguel L. C. Côcco C. I. Yamamoto C. CorrêaJr M. A. A. De Castro-Prado 《Folia microbiologica》2009,54(6):493-498
Eucalyptus globulus essential oil was evaluated for its genotoxic potential using a somatic segregation assay and a diploid strain of the fungus
Aspergillus nidulans, heterozygous for nutritional and conidia color markers. The main compounds of the current essential oil sample were eucalyptol
(49.0 %), α-pinene (8.9), β-pinene (1.5), globulol (6.9), α-eudesmol (1.12), spathulenol (1.42), γ-cadinene (1.45), trans-β-elemenone (1.23) and aromandendrene (2.3), totaling 74 % of oil. Oil at 0.12 and 0.25 μL/mL was found to increase the mitotic
instability of the original diploid strain and the number of diploid mitotic recombinants of A. nidulans. The genotoxicity of the oil was associated with the induction of mitotic crossing-over or with oil-broken chromosomes. 相似文献
3.
E. Vollbrecht R. Heckmann V. Wray M. Nimtz S. Lang 《Applied microbiology and biotechnology》1998,50(5):530-537
The bacterium Tsukamurella sp. nov., isolated from soil, was found to produce novel glycolipids when grown on sunflower oil as the sole carbon source.
The glycolipids were isolated by chromatography on silica columns and their structures elucidated using a combination of multidimensional
NMR and MS techniques. The three main components are 2,3-di-O-acyl-α-d-glucopyranosyl-(1-1)-α-d-glucopyranose, 2,3-di-O-acyl-β-d-glucopyranosyl-(1-2)-4,6-di-O-acyl-α-d-glucopyranosyl-(1-1)-α-d-glucopyranose and 2,3-di-O-acyl-β-d-glucopyranosyl-(1-2)-β-d-galactopyranosyl-(1-6)-4,6-di-O-acyl-α-d-glucopyranosyl-(1-1)-α-d-glucopyranosl which are linked to fatty acids varying in chain length from C4 to C18. The glycolipids are mainly extracellular but are also found attached to the cell walls. During the cultivation the composition
of the glycolipids changed from disaccharide- to tri- and tetrasaccharide lipids. The glycolipids show good surface-active
behaviour and have antimicrobial properties.
Received: 22 May 1998 / Received revision: 24 August 1998 / Accepted: 26 August 1998 相似文献
4.
Mary Ndungu Wilber Lwande Ahmed Hassanali Lambert Moreka Sumesh Chander Chhabra 《Entomologia Experimentalis et Applicata》1995,76(3):217-222
The repellency of the essential oil of the shrubCleome monophylla (Family: Capparidaceae) and identified constituents of the oil were evaluated against the livestock tick,Rhipicephalus appendiculatus and the maize weevil,Sitophillus zeamais. In a tick climbing repellency bioassay, the oil ofC. monophylla exhibited repellency which, at the highest dose, was comparable to that of the commercial arthropod repellent N,N-diethyl
toluamide (DEET). In a Y-tube olfactometer bioassay,C. monophylla oil showed higher or comparable repellency againstS. zeamais relative to DEET at all the doses tested. 14 Compounds were identified in theC. monophylla oil by GC, GC-MS and coinjection with authentic samples. Terpenolene was found to occur in largest quantity (14%) followed
by 1-α-terpeneol (10%), pentacosane (9%), (α+β)-humulene (8%), phytol (5%) and 2-dodecanone (4%). The most repellent components
againstR. appendiculatus andS. zeamais were 1-α-terpeneol and 2-dodecanone. The overall pattern of repellency activity of theC. monophylla constituents with respect to the two arthropods was, however, different. The potential ofC. monophylla in tick and maize weevil control is discussed. 相似文献
5.
The effects of 24-epibrassinolide on growth, photosynthesis, chlorophyll content, carbohydrate fractions, and essential oil
content of rose scented geranium (Pelargonium graveolens (L.) Herit) were investigated. Foliar application of 24-epibrassinolide at 0.5, 1, and 3 μM concentrations substantially
increased the growth. 24-epibrassinolide at all concentrations improved herbage yield as reflected in the increase of foliar
biomass. Exogenous application of 24-epibrassinolide increased the rate of photosynthesis. Growth promotion was also associated
with increased chlorophyll content and resulted in the accumulation of carbohydrate fractions. At 3-μM concentration, 24-epibrassinolide
increased the total content of essential oils. The quantitative analysis of geranium oil from the geranium plant treated with
3-μM concentration revealed an increase in geraniol content and decrease in citronellol content. The present study demonstrates
a positive impact of the new group of phytohormones on the performance of geranium plant, a highly valued aromatic plant. 相似文献
6.
Hannibal T. Musarurwa Lerí Koegelenberg Nokwanda P. Makunga 《Journal of Plant Growth Regulation》2012,31(2):207-220
The effects of nitrogen, potassium, water stress, and phytohormones were studied using a Salvia stenophylla (Burch. ex Benth.) microplant system. In vitro regeneration was monitored and then followed with volatile secondary metabolite profiling
through headspace solid-phase microextraction gas chromatography. Plantlet growth was most prolific on half-strength Murashige
and Skoog medium without phytohormones. An increase in macronutrients supplied to the microplants enhanced accumulation of
the commercially important (−)-α-bisabolol, while no significant changes to the relative abundance of β-bisabolene, α-muurolene,
α-patchoulene, and D-limonene (among others) became apparent. Water-stressed plants, treated with sorbitol and polyethylene
glycol, had a lowered rooting capacity in vitro. Overall, as a plant production system, micropropagation did not have deleterious
effects on the biochemistry of S. stenophylla as no significant differences in metabolic profiles existed between conventional garden plants and in vitro propagules, regardless
of phytohormone treatment. We also show that nutrient manipulation can be used efficiently as a strategy for positively altering
secondary metabolism. This will ultimately benefit the domestication of this commercially important medicinal herb. 相似文献
7.
Marc Lahaye Enrique Alvarez-Cabal Cimadevilla Ralph Kuhlenkamp Bernard Quemener Vincent Lognoné Patrick Dion 《Journal of applied phycology》1999,11(1):1-7
The chemical composition and structures of several ulvan extracts isolated from various Ulva species were studied. They were
all composed mainly of rhamnose, glucuronic acid, xylose, glucose and sulphate with smaller amounts of iduronic acid and traces
of galactose. Proteins were also present, most likely as contaminants. Precise quantification of the uronic acid content by
chemical-enzymatic hydrolysis coupled to HPAEC-PAD analysis and by colorimetry was not achieved, most likely due to the incomplete
hydrolysis of glucuronan segments, inadequate HPAEC-pulsed-amperometric response factor for iduronic acid and to a possible
differential colorimetric response of the two uronic acids. 13C NMR spectroscopic investigation of different ulvans demonstrated that they were all based on ulvanobiuronic acid 3-sulphate
A and B repeating units [β-D-Glc pA-(1->4)-α-L-Rhap3S and α-L-IdopA-(1->4)-α-L-Rha p3S, respectively] as well as contiguous
β 1->4 linked D-glucuronic acids possibly occurring either in ulvan or as a separate glucuronan. Marked variations in the
content of the repeating structures were seen among the different samples. However, due to the limited number of samples studied,
no conclusion was reached concerning the effects of species and ecophysiological conditions on the chemistry of ulvan.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
Fedonenko YP Boiko AS Zdorovenko EL Konnova SA Shashkov AS Ignatov VV Knirel YA 《Biochemistry. Biokhimii?a》2011,76(7):797-802
Lipopolysaccharides and O-specific polysaccharides were isolated from the outer membrane of bacterial cells of three strains
belonging to two Azospirillum species, and their structures were established by monosaccharide analysis including determination of the absolute configurations,
methylation analysis, and one- and two-dimensional NMR spectroscopy. It was shown that while having the identical composition,
the O-polysaccharides have different branched tetrasaccharide repeating units. Two neutral polysaccharides were found in the
lipopolysaccharide of A. brasilense 54, and the structure for the predominant O-polysaccharide was determined. The structural data, together with results of
serological studies, enabled assignment of strains examined to a novel serogroup, III. The chemical basis for the serological
relatedness among the azospirilla of this serogroup is presumably the presence of a common →3)-α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-α-L-Rhap-(1→oligosaccharide motif in their O-polysaccharides. 相似文献
9.
A. S. Boiko O. N. Smol’kina Yu. P. Fedonenko E. L. Zdorovenko V. V. Kachala S. A. Konnova V. V. Ignatov 《Microbiology》2010,79(2):197-205
Lipopolysaccharides (LPS) and O-specific polysaccharides (OPS) were obtained from the outer membrane of four Azospirillum strains previously assigned to serogroup I based on the serological affinity revealed by the antibodies (AB) to the LPS of
A. brasilense Sp245. Investigation, including determination of monosaccharide composition, methylation analysis, and one- and two-dimensional
NMR spectroscopy, was carried out to determine the OPS structure. The OPSs of A. brasilense Sp107 and S27 and of A. lipoferum RG20a were found to have an identical structure of repeating units represented by a linear penta-D-rhamnan, as was previously
described for the OPSs of A. brasilense Sp245 and SR75. The OPS of A. brasilense SR15 was found to consist of tetrasaccharide repeating units of the following structure: → 2)-α-D-Rhap-(1 → 2)-β-D-Rhap-(1 → 3)-α-D-Rhap-(1 → 2)-α-D-Rhap-(1 →. An opine compound, Nδ-(1-carboxyethyl)-ornithine, closely associated with the LPS of A. brasilense SR15, was identified in azospirilla for the first time. The presence of a 6-deoxisugar (D-rhamnose) in the OPS structure
was shown to be the chemical basis of the serological similarity and the reason for classification of these strains within
the serogroup I. 相似文献
10.
In this study, human α-1,4-N-acetylglucosaminyltransferase (α4GnT) fused with GFPuv (GFPuv-α4GnT) was expressed using both a transformed cell system and silkworm larvae. A Tn-pXgp-GFPuv-α4GnT cell line, isolated after expression vector transfection, produced 106 mU/ml of α4GnT activity in suspension culture.
When Bombyx mori nucleopolyhedrovirus containing a GFPuv-α4GnT fusion gene (BmNPV-CP
−/GFPuv-α4GnT) bacmid was injected into silkworm larvae, α4GnT activity in larval hemolymph was 352 mU/ml, which was 3.3-fold higher
than that of the Tn-pXgp-GFPuv-α4GnT cell line. With human calnexin (CNX) or human immunoglobulin heavy chain-binding protein (BiP, GRP78) coexpressed under
the control of the ie-2 promoter, α4GnT activity in larval hemolymph increased by 1.4–2.0-fold. Moreover, when BmNPV-CP
−/GFPuv-α4GnT bacmid injection was delayed for 3 h after BmNPV-CP
−/CNX injection, the α4GnT activity increased significantly to 922 mU/ml, which was 8.7-fold higher than that of the Tn-pXgp-GFPuv-α4GnT cell line. Molecular chaperone assisted-expression in silkworm larvae using the BmNPV bacmid is a promising tool for
recombinant protein production. This system could lead to large-scale production of more complex recombinant proteins. 相似文献
11.
Hannibal T. Musarurwa Johannes van Staden Nokwanda P. Makunga 《Plant Growth Regulation》2010,61(3):287-295
The aromatic medicinal plant Salvia stenophylla contains α-bisabolol, making this plant an important contributor to the aromatherapy and cosmetic industries in South Africa.
Due to its commercial importance, the cultivation of this plant using an in vitro system was considered. Firstly, seedlings
were raised in vitro after breaking dormancy with light, smoke-water or chemical scarification treatments. Germination improved
when seeds were smoke-treated or soaked in 70% (v/v) H2SO4. Vigorous plantlet regeneration was achieved when seedling explants were cultured on Murashige and Skoog (1962) medium with 5.7 μM IAA and 8.9 μM BA. The potential regeneration capacity for this protocol was estimated and over 1,000
plantlets can be produced from a single shoot (6.67 cm with 4–6 nodes) over a period of 3 months. Plants rooted easily regardless
of their growth medium. This was followed by their successful rapid establishment and normal growth out of culture (75%).
Finally, the volatile compounds in in vitro plants were compared to ex vitro plants via headspace solid phase microextraction
linked to gas chromatography–mass spectrometry. The chemical complexity of microplants was similar to wild plants with in
vitro plants continuing to produce α-bisabolol (21%) at high levels. 相似文献
12.
Lipopolysaccharides (LPSs) of two strains Pragia fontium 97U116 and 27480 were isolated and characterized; they were close to those of other representatives of the family Enterobacteriaceae in fatty acid composition and contained, respectively, 3-hydroxytetradecanoic acid as the predominant component (45.8 and 45.1%), tetradecanoic (23.5 and 28.9%), hexadecanoic (12.6 and 7.9%), hexadecenoic (12.6 and 7.9%), and dodecanoic (4.9 and 4.2%) fatty acids. The O-specific polysaccharides consisted of linear penta- and tetrasaccharide repeating units: →2)-α-D-Galf-(1→3)-α-L-Rhap2Ac-(1→4)-α-D-GlcpNAc-(1→2)-α-L-Rhap-(1→3)-β-D-GlcpNAc-(1→ →4)-β-D-ManpNAc3NAcA-(1→2)-α-L-Rhap-(1→3)-β-L-Rhap-(1→4)-α-D-GlcpNAc-(1→ The LPSs of P. fontium 97U116 and 27480 were serologically active and belonged to different serogroups; they were less toxic than those of strain E. coli O55:B5, but more pyrogenic than the Pyrogenal preparation. 相似文献
13.
Antibacterial effect of 17 ammonium compounds of the type of N,N′-bis(alkyldimethyl)-α,ω-alkanediammonium dibromides was tested
on anaerobically sporulating bacteria of the genusClostridium. A sizable antibacterial activity was displayed by five N,N′-bis(alkyldimethyl)-1,6-hexanediammonium dibromides and by four
N,N′-bis(decyldimethyl)-α,ω-alkanediammonium dibromides. These compounds exhibited activity higher than, or comparable with,
that of the reference standards Ajatin and Septonex. The maximum antibacterial activity was found in compounds whose alkyl
chain contained 9–12 carbon atoms. Compounds with a lower number of carbon atoms in the chain (less than 8) exhibited a low
activity. 相似文献
14.
Sander W Tas Margriet J Vervoordeldonk Najat Hajji Michael J May Sankar Ghosh Paul P Tak 《Arthritis research & therapy》2006,8(4):R86-9
Nuclear factor (NF)-κB is a key regulator of synovial inflammation. We investigated the effect of local NF-κB inhibition in
rat adjuvant arthritis (AA), using the specific IκB kinase (IKK)-β blocking NF-κB essential modulator-binding domain (NBD)
peptide. The effects of the NBD peptide on human fibroblast-like synoviocytes (FLS) and macrophages, as well as rheumatoid
arthritis (RA) whole-tissue biopsies, were also evaluated. First, we investigated the effects of the NBD peptide on RA FLS
in vitro. Subsequently, NBD peptides were administered intra-articularly into the right ankle joint of rats at the onset of disease.
The severity of arthritis was monitored over time, rats were sacrificed on day 20, and tissue specimens were collected for
routine histology and x-rays of the ankle joints. Human macrophages or RA synovial tissues were cultured ex vivo in the presence or absence of NBD peptides, and cytokine production was measured in the supernatant by enzyme-linked immunosorbent
assay. The NBD peptide blocked interleukin (IL)-1-β-induced IκBα phosphorylation and IL-6 production in RA FLS. Intra-articular
injection of the NBD peptide led to significantly reduced severity of arthritis (p < 0.0001) and reduced radiological damage (p = 0.04). This was associated with decreased synovial cellularity and reduced expression of tumor necrosis factor (TNF)-α
and IL-1-β in the synovium. Incubation of human macrophages with NBD peptides resulted in 50% inhibition of IL-1-β-induced
TNF-α production in the supernatant (p < 0.01). In addition, the NBD peptide decreased TNF-α-induced IL-6 production by human RA synovial tissue biopsies by approximately
42% (p < 0.01). Specific NF-κB blockade using a small peptide inhibitor of IKK-β has anti-inflammatory effects in AA and human RA
synovial tissue as well as in two important cell types in the pathogenesis of RA: macrophages and FLS. These results indicate
that IKK-β-targeted NF-κB blockade using the NBD peptide could offer a new approach for the local treatment of arthritis. 相似文献
15.
Han-Seop Bea Sang-Hyeup Lee Hyungdon Yun 《Biotechnology and Bioprocess Engineering》2011,16(2):291-296
In this study, (R)-3-fluoroalanine was asymmetrically synthesized from 3-fluoropyruvate (F-pyruvate) and (S)-α-methylbenzylamine (MBA) using recombinant ω-transaminase (TA) from Vibrio fluvialis JS17. The reaction was severely inhibited by acetophenone (deaminated product of α-MBA). In the presence of 5 mM acetophenone,
the reactivity of the enzyme towards F-pyruvate decreased by 78%. To overcome the product inhibition by acetophenone, a biphasic
reaction was successfully used. The conversion of F-pyruvate into (R)-3-fluoroalanine (enatiomeric exess (e.e.) > 99%) was about 95% in the biphasic system (75 mM F-pyruvate, 100 mM (S)-α-MBA, and 3.0 U/mL), whereas 31% was obtained without product extraction. The use of racemic α-MBA as an amino donor instead
of (S)-α-MBA can reduce the reaction cost and also produce chiral amines through kinetic resolution. When the kinetic resolution
of racemic α-MBA (40 mM) was carried out with F-pyruvate (30 mM) and ω-TA (3.0 U/mL) in 100 mM phosphate buffer (pH 7.0),
the e.e. of (R)-α-MBA reached 98.4% with 52.2% conversion for 10 h and 21 mM (R)-3-fluoroalanine was produced with 70% conversion and an e.e. > 99%. 相似文献
16.
The essential oils from the aerial parts of catmint (Nepeta meyeri Benth.) were analyzed by hydrodistillation with GC–MS. Fourteen compounds were identified in the yellowish essential oil
of the plant, representing more than 99.07% of the oil, of which the major components were found to be 4aα,7α,7aβ-nepetalactone
(83.4%) and 4aα,7α,7aα-nepetalactone (8.83%). The oils were characterized by relatively high content of oxygenated monoterpenes,
and were tested on the germination and antioxidative systems in early seedlings of seven weed species (Amaranthus retroflexus L., Bromus danthoniae Trin., Bromus intermedius Guss., Chenopodium album L., Cynodon dactylon L., Lactuca serriola L., and Portulaca oleracea L.) and autotoxicity. The essential oil of N. meyeri inhibited seed germination by more than 50% in three weed species (B. danthoniae, B. intermedius, and L. serriola) when applied at a concentration of 0.01%. When the same oils were applied at 0.02% concentration, the inhibition of germination
was more than 70% in two weeds (C. album and C. dactylon) and was 100% in four weeds (A. retroflexus, B. danthoniae, B. intermedius, and L. serriola). The essential oils increased CAT activity in all the weed species and decreased SOD activity, except in A. retroflexus. POX activity did not exhibit a revealing situation in the weed species tested. The essential oils increased the level of
lipid peroxidation and hydrogen peroxide (H2O2) concentration in all the weeds studied. Our results show that the essential oils of N. meyeri have an important phytotoxic effect on seed germination and, consequently, seedling growth by exhausting antioxidative system
of the weeds. The phytotoxic activity of the essential oils may be attributed to their relatively high content of oxygenated
monoterpenes, especially 4aα,7α,7aβ-nepetalactone. It can be suggest that the essential oils of N. meyeri have the potential to be used as a bioherbicide. 相似文献
17.
ARA267-α is a newly identified androgen receptor coactivator. In order to further elucidate its precise role in cells, using
the ARA267-α fragment containing four PHD and one SET conserved domains as bait we revealed an ARA267-α-PHD-SET-interacting
protein, death receptor-6 (DR6), in the yeast two-hybrid screening. DR6 is the member of TNF receptor family and has a death
domain in its intracellular cytoplasmic portion (DR6cp) to mediate the cell apoptosis. The interaction between ARA267-α-PHD-SET
and DR6cp was confirmedin vitro andin vivo. Our finding implied that androgen signaling pathway might cross talk with apoptosis signaling pathway through the interaction
between ARA267-α and DR6. 相似文献
18.
In this study, the effect of Matricaria recutita L. essential oil (MEO) on the central nervous system (CNS) of mice was investigated using some behavioral methods. Chemical profiling both by GC and GC-MS analyses of the hydrodistilled essential oil of M. recutita revealed α-bisabolol oxide A (28%), α-bisabolol oxide B (17.1%), (Z)-β-Farnesene (15.9%) and α-bisabolol (6.8%) as the main components. Changes induced by MEO (25, 50 and 100 mg/kg) and reference drug caffeine (25 mg/kg) in spontaneous locomotor activities and motor coordinations of mice were investigated by activity cage measurements and Rota-Rod tests, respectively. Open field, social interaction and elevated plus-maze tests were applied to assess the emotional state of the animals. Further, tail-suspension test was performed for evaluating the effect of MEO on depression levels of mice. As a result, at 50 and 100 mg/kg, MEO significantly increased the numbers of spontaneous locomotor activities, exhibited anxiogenic effect in the open field, elevated plus-maze and social interaction tests and decreased the immobility times of animals in tail suspension tests. The falling latencies in Rota-Rod tests did not change. This activity profile of MEO was similar to the typical psychostimulant caffeine. The exact mechanism of action underlying this stimulant-like effect should be clarified with further detailed studies. 相似文献
19.
Bobbie Ann Austin Cassandra M. James Peter Härle Daniel J. J. Carr 《Biological procedures online》2006,8(1):55-62
The application of naked DNA containing type I interferon (IFN) transgenes is a promising potential therapeutic approach for
controlling chronic viral infections. Herein, we detail the application of this approach that has been extensively used to
restrain ocular HSV-1 infection, for antagonizing vaginal HSV-2 infection. We show that application of IFN-α1, -α 5, and -β
transgenes to vaginal mouse lumen 24 hours prior to HSV-2 infection reduces HSV-2 mediated mortality by 2.5 to 3-fold. However,
other type I IFN transgenes (IFN- α 4, -α 5, -α 6, and -α 9) are non effectual against HSV-2. We further show that the efficacy
of IFN-1 transgene treatment is independent of CD4+ T lymphocytes. However, in mice depleted of CD8+ T lymphocytes, the ability
of IFN-α 1 transgene treatment to antagonize HSV-2 was lost. 相似文献
20.
A. V. Perepelov Bin Liu S. N. Senchenkova A. S. Shashkov S. D. Shevelev Lu Feng Lei Wang Y. A. Knirel 《Biochemistry. Biokhimii?a》2010,75(1):19-24
On mild acid degradation of the lipopolysaccharide of Escherichia coli O108, the O-polysaccharide was isolated and studied by sugar analysis and one- and two-dimensional 1H- and 13C-NMR spectroscopy. The polysaccharide was found to contain an unusual higher sugar, 5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-d-galacto-non-2-ulosonic acid (di-N-acetyl-8-epilegionaminic acid, 8eLeg5Ac7Ac). The following structure of the tetrasaccharide repeating unit of the polysac-charide
was established: →4)-α-8eLegp5Ac7Ac-(2→6)-α-D-Galp-(1→3)-α-L-FucpNAc-(1→3)-α-D-GlcpNAc-(1→. Functions of the E. coli O108 antigen biosynthetic genes, including seven putative genes for synthesis of 8eLeg5Ac7Ac, were assigned by sequencing
the O-antigen gene cluster along with comparison with gene databases and known biosynthetic pathways for related nonulosonic
acids. 相似文献