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1.
Essential oil of the subterranean part of Cacalia tangutica (Maxim.) Hand.-Mazz was analyzed by gas chromatography (GC)-mass spectrum (MS) tech-nique in two different capillary columns of different polar-ities. Thirty-one components were identified in the oil and the main compounds were a-zingiberene (13.49%), germa-crene D (10.76%), a-pinene (8.54%), caryophyllene(Z-) (6.36%), linalool (6.16%), β-myrcene (4.89%),β-ocimene (Z-) (4.40%)and ocimenone(Z-) (3.58%). The antimicro-bial activity of the oil was evaluated against 2 fungi and 12 bacteria including 6 clinically isolated strains using the agar disc diffusion and broth microdilution methods. The results show that the oil presented a broad antimicro-bial spectrum and had better antimicrobial activity against yeast and gram-positive bacteria. The minimum inhibitory concentration values were 0.16-5.00 g/L and minimum bactericidal concentration values were 0.16-5.00 g/L.  相似文献   

2.
Seven alkaloids were isolated from the seeds of Ammopiptanthus mongolica by thin layer chromatography and silica gel column chromatography, and the chemical structures of five alkaloids, 17-oxosparteine, β-isosparteine, 3α-hydroxysparteine, sparteine, and 3β-hydroxysparteine were identified by 1H nuclear magnetic resonance (NMR) and electron ionization mass spectrum (EIMS). __________ Translated from Journal of Lanzhou University (Natural Sciences), 2007, 43(2): 43–46 [译自: 兰州大学学报(自然科学版)]  相似文献   

3.
The composition of the essential oils obtained from the leaves and the flowers of Achillea ligustica (Asteraceae) growing in Sicily has been studied. The main constituents of the leaves were 4-terpineol (19.3%), carvone (8.9%), γ-terpinene (7.2%) and β-phellandrene (6.8%). 4-terpineol (12.0%), carvone (10.0%), and β-phellandrene (5.4%), along with linalool (20.4%) and cedrol (4.3%) were detected in the flower’s oil. Furthermore, the antimicrobial activity of the essential oils and of some of the main constituents were assayed on bacteria and fungi. In memory of Prof. Ivano Morelli (1940–2005)  相似文献   

4.
The essential oil obtained by hydrodistillation from the leaves of micropropagated plants of Artemisia amygdalina was analyzed by capillary GC–FID and GC–MS and compared with that obtained from the leaves of field growing parent plants. The oil yield from the micropropagated plants was lower (0.05% v/w) than the oil yield obtained from field-grown plants (0.2% v/w). The major constituents of the field-grown plants were p-cymene (21.0%), 1,8-cineole (24.9%), α-terpineol (5.9%), β-caryophyllene (4.7%), germacrene D (4.0%), while as the major constituents from the micropropagated plants were p-cymene (11.3%),1,8-cineole (10.2%), borneol (7.9%), α-longipinene (5.5%), α-copaene (5.5%) and β-caryophyllene (17%). The essential oil from field-grown plant was dominated by the presence of oxygenated monoterpenes (41.5%), monoterpene hydrocarbons (35.9%) and sesquiterpene hydrocarbons (16.3%) while as the essential oil of micropropagated plants was characterized by sesquiterpene hydrocarbons (40.0%), oxygenated monoterpenes (25.2%) and monoterpene hydrocarbons (21.6%).  相似文献   

5.
Pseudomonas resinovorans harbors two isogenic poly(hydroxyalkanoates) (PHAs) synthase genes (phaC1 Pre , phaC2 Pre ) responsible for the production of intracellular medium-chain-length (mcl-)PHAs. Sequence analysis showed that the putative gene-products of these genes contain a conserved α/β-hydrolase fold in the carboxy-terminal half of the proteins. Hybrid genes pha7 and pha8 were constructed by exchanging the α/β-hydrolase-fold coding portions of phaC1 Pre and phaC2 Pre at the 3′ terminal. When grown with decanoate as carbon source, the pha7- or pha8-transformed Escherichia coli LS1298 produced PHAs containing 73–75% β-hydroxydecanoate (β-HD) and 25–27% β-hydroxyoctanoate (β-HO). Deletion mutants, Δpha7 and Δpha8, were isolated during the PCR-based construction of pha7 and pha8, respectively. Cells harboring these mutants produced PHAs containing 55–60 mol% β-HD and 40–45 mol% β-HO. These results demonstrate the feasibility of generating active hybrid mcl-PHA synthase genes and their mutants with the potential of producing polymers having a varied repeat-unit composition.  相似文献   

6.
Gas chromatography-flame ionisation detection (GC-FID) and gas chromatography–mass spectrometry (GC–MS) analyses of the essential oils of leaves and fruits of the ornamental Shinus molle L. were reported and their allelopathic effect on wheat (Triticum aestivum L.) was evaluated. Qualitative and quantitative differences between fruit and leaf oils were observed. Both oils were rich in monoterpene hydrocarbons and the major constituents were limonene and β-phellendrene (35.9–65.4%), α-phellendrene (24.3–20.1%), myrcene (12.8–7.7%) and α-pinene (5.9–1.7%) for fruits and leaves, respectively. Both essential oils showed a dose-dependent allelopathic activity on wheat germination and radicle elongation with leaf oil being the more phytotoxic.  相似文献   

7.
Seven flavonol glycosides were isolated from the leaves ofT. apetalon. They were identified chromatographically and spectrally to be: quercetin/kaempferol 3-O-α-arabinopyranosyl-(1→6)-β-galactopyranoside (TQ and TK), quercetin/kaempferol 3-O-[2‴-O-acetyl-α-arabinopyranosyl]-(1→6)-β-galactopyranoside (TAQ and TAK), quercetin 3-O-β-glucoside (ISQ), isorhamnetin 3-O-α-arabinopyranosyl-(1→6)-β-galactopyranoside (TI) and isorhamnetin 3-O-[2‴-O-acetyl-α-arabinopyranosyl]-(1→6)-β-galactopyranoside (TAI). TQ, TAQ, TI and TAI were major constituents. This is the first report on two new isorhamnetin-type glycosides, TI and TAI. The seven flavonol glycosides identical to those ofT. apetalon were isolated and identified in the leaves ofT. kamtschaticum; TQ and TAQ were also major components, but TI and TAI were only minor components. TI and TAI were not detected in the leaves ofT. tschonoskii. These leaf-flavonoid patterns were discussed from a chemosystematic point of view. Part 3 in the series “Studies of the flavonoids of the genusTrillium”. For Part 2 see Yoshitamaet al., (1997) J. Plant Res.110: 379–381.  相似文献   

8.
The objective of this study was to characterize the bacterial community composition in the bulk soil, rhizosphere soil and root tissue of the tomato plant (Lycopersicum esculentum Mill). 16S ribosomal DNA (rDNA) from the bacterial community was amplified using PCR, and sequence analysis of 16S rDNA clones was subsequently used for bacterial identification and phylogenetic classification. Phylogenetic analysis of clones (total of 68) from the bulk soil, rhizosphere and root tissues showed that about 50% of the bacteria belonged to the α-, β-, γ-, and δ-Proteobacteria or Cytophaga–Flavobacterium–Bacteroides (CFB) phyla, with only one high G+C clone identified. A number of diverse bacteria were identified within Proteobacteria, while 87% of the bacteria belonged to the genus Flavobacterium within the CFB phylum, which is a unique finding for tomato plants. Our results will be of interest to those wanting to identify bacteria that can promote plant growth or resistance to diseases.  相似文献   

9.
A moderately thermophilic, sporeforming bacterium able to reduce amorphous Fe(III)-hydroxide was isolated from ferric deposits of a terrestrial hydrothermal spring, Kunashir Island (Kurils), and designated as strain Z-0001. Cells of strain Z-0001 were straight, Gram-positive rods, slowly motile. Strain Z-0001 was found to be an obligate anaerobe. It grew in the temperature range from 45 to 70°C with an optimum at 57–60°C, in a pH range from 5.9 to 8.0 with an optimum at 7.0–7.2, and in NaCl concentration range 0–3.5% with an optimum at 0%. Molecular hydrogen, acetate, peptone, yeast and beef extracts, glycogen, glycolate, pyruvate, betaine, choline, N-acetyl-d-glucosamine and casamino acids were used as energy substrates for growth in presence of Fe(III) as an electron acceptor. Sugars did not support growth. Magnetite, Mn(IV) and anthraquinone-2,6-disulfonate served as the alternative electron acceptors, supporting the growth of isolate Z-0001 with acetate as electron donor. Formation of magnetite was observed when amorphous Fe(III) hydroxide was used as electron acceptor. Yeast extract, if added, stimulated growth, but was not required. Isolate Z-0001 was able to grow chemolithoautotrophicaly with molecular hydrogen as the only energy substrate, Fe(III) as electron acceptor and CO2 as the carbon source. Isolate Z-0001 was able to grow with 100% CO as the sole energy source, producing H2 and CO2, requiring the presence of 0.2 g l−1 of acetate as the carbon source. The G+C content of strain Z-0001T DNA G+C was 47.8 mol%. Based on 16S rRNA sequence analyses strain Z-0001 fell into the cluster of family Peptococcaceae, within the low G+C content Gram-Positive bacteria, clustering with Thermincola carboxydophila (98% similarity). DNA–DNA hybridization with T. carboxydophila was 27%. On the basis of physiological and phylogenetic data it is proposed that strain Z-0001T (=DSMZ 14005, VKM B-2307) should be placed in the genus Thermincola as a new species Thermincola ferriacetica sp. nov. The GenBank accession number for the sequence reported in the paper is AY 631277.  相似文献   

10.
Summary Endosulfan is an insecticide used on many vegetable crops. In mushroom cultivation, vegetable materials used as a growth substrate may contain residues of endosulfan that may accumulate in the final mushroom biomass. After preparing the substrate, it is subjected to pasteurization and/or composting and then inoculated with the desired fungus. The purpose of this research was to determine the rate and extent of endosulfan reduction from a grass substrate that was either composted or sterilized by autoclaving. In addition, the rate and extent of removal of endosulfan from substrate colonized with Pleurotus pulmonarius was determined. The degradation of 65 mg/kg endosulfan was analyzed on both, the substrate preparation and the culture of P. pulmonarius on the grass Digitaria decumbens. During composting in presence of Ca(OH)2 for 120 h, the concentrations of α and β endosulfan were reduced by 61.4 and 49.5% respectively, significantly higher compared with the control (without Ca(OH)2,) in which the reduction was 38.5%. After sterilization the concentration of α and β endosulfan was reduced by 84.8 and 87.5% respectively. After the colonization of substrate by P. pulmonarius (15 days after spawning) α and β endosulfan were reduced by 96% and at the end of cultivation (35 days after spawning) were reduced by 99%. When carpophores were analyzed, residues of α and β endosulfan were observed between 0.019–0.084 mg/kg. The results showed that α and β endosulfan were partially removed during the preparation of substrate and entirely eliminated during fungal colonization on the substrate.  相似文献   

11.
The cloning, sequencing and functional expression of Sgβ1, a novel locust (Schistocerca gregaria) non-α nicotinic acetylcholine receptor (nAChR) subunit is described. This subunit shows 80% identity with the Drosophila melanogaster Dβ1 and 92% identity with the Locusta migratoria β1, non-α subunits but only 38% identity to Sgα1 (also referred to as αL1), a previously cloned S. gregaria nAChR α-subunit. When expressed in Xenopus laevis oocytes, Sgβ1 does not respond to nicotine. Responses to nicotine are observed, however, in oocytes co-expressing Sgα1 and Sgβ1, but the pharmacology is indistinguishable from that of currents produced by expressing Sgα1 alone. We conclude that either Sgβ1 does not co-assemble with Sgα1, or that it is unable to contribute to the functional properties of the receptor, in the Xenopus oocyte expression system.  相似文献   

12.
Molecular characterization based on 16s rDNA gene sequence analysis of bacterial colonies isolated from endosulfan contaminated soil showed the presence of Ochrobacterum sp, Burkholderia sp, Pseudomonas alcaligenes, Pseudomonas sp and Arthrobacter sp which degraded 57–90% of α-endosulfan and 74–94% of β-endosulfan after 7days. Whole cells of Pseudomonas sp and Pseudomonas alcaligenes showed 94 and 89% uptake of α-isomer and 86 and 89% of β-endosulfan respectively in 120 min. In Pseudomonas sp, endosulfan sulfate was the major metabolite detected during the degradation of α-isomer, with minor amount of endosulfan diol while in Pseudomonas alcaligenes endosulfan diol was the only product during α-endosulfan degradation. Whole cells of Pseudomonas sp also utilized 83% of endosulfan sulfate in 120 min. In situ applications of the defined consortium consisting of Pseudomonas alcaligenes and Pseudomonas sp (1:1) in plots contaminated with endosulfan showed that 80% of α-endosulfan and 65% of β-endosulfan was degraded after 12 weeks of incubation. Endosulfan sulfate formed during endosulfan degradation was subsequently degraded to unknown metabolites. ERIC-PCR analysis indicated 80% survival of introduced population of Pseudomonas alcaligenes and Pseudomonas sp in treated plots.  相似文献   

13.
The composition of the essential oil from the wormwood sage (Artemisia frigida Willd., Asteraceae) of populations growing in the Altai Territory, the Altai Republic, the Khakass Republic, the Tuva Republic, and the East-Kazakhstan region of the Republic of Kazakhstan and the representative species of the silver-leaved wormwood Artemisia argyrophylla Ledeb. growing in the Republic Altai has been studied by chromato-mass spectrometry. An analysis of 15 samples of the essential oil from A. frigida obtained over a period from 1999 to 2007 indicates that samples from different populations have similar sets of the main components: α-pinene (0.2–7.8%), camphene (1.9–5.8%), 1,8-cineole (8.9–33.8%), camphor (6.7–40.0%), borneol (3.9–12.3%), terpine-4-ol (1.5–6.5%), bornyl acetate (1.4–22.0%), and germacrene D (1.4–14.6%). Some samples contain substantial amounts of α- and β-thujones (in total up to 19.1%), which are completely absent in other samples. Some samples contain santolina alcohol (up to 13.8%) and its acetate (up to 4.8%). As differentiated from A. frigida, the essential oil of A. argyrophylla contains yomogi alcohol (1.2%), artemisia ketone (12.9%), artemisia alcohol (3.1%), artemisia alcohol acetate (3.9%), and small amounts of camphor (3.2%), borneol (0.3%), and bornyl acetate (0.2%).  相似文献   

14.
This study was undertaken to characterize the essential oil (EO) of Artemisia arborescens growing wild in Sicily. EO, extracted by steam distillation, was examined for its chemical composition and for its capability to inhibit some food-borne pathogen bacteria. A total of 43 compounds (13 monoterpene hydrocarbons, 14 oxygenated monoterpenes, 10 sesquiterpene hydrocarbons, three oxygenated sesquiterpenes and less amount of other three compounds), which account 93.73% of the total oil, were identified by gas chromatography and gas chromatography–mass spectrometry. Oxygenated monoterpenes (57.32%) constituted the main fraction, with β-thujone as the main compound (45.04%), followed by the sesquiterpene hydrocarbon chamazulene (22.71%). Undiluted EO showed a large inhibition spectrum against strains of Listeria monocytogenes (34 out of 44), whilst it was ineffective against enterobacteria and salmonellas. The minimum inhibition concentration (MIC) was evaluated for the two most sensitive strains (L. monocytogenes 186 and 7BO) at two cellular concentrations (106 and 107 CFU ml−1). The lowest MIC (0.625 μl ml−1, dilution of oil with acetone) was found for strain L. monocytogenes 186 at 106 CFU ml−1.  相似文献   

15.
The gene which encodes (R)-specific carbonyl reductase (rCR) from Candida parapsilosis CCTCC M203011 was cloned, sequenced and compared with genes from the GenBank. The results indicated that rCR gene was 1011 bp, encoding a protein of 336 amino acids with a molecular weight of 35.9 kDa, and its nucleotide sequence showed 99% similarity to those of other members of the alcohol dehydrogenase superfamily. The rCR gene could express in recombinant strain Escherichia coli JM109, and the expression plasmid could produce (R)-1-pheny-1,2-ethanediol (100% e.e., 80.14% yield) from β-hydroxyacetophenone without any additive to regenerate NAD+ from NADH. __________ Translated from Microbiology, 2006, 33(4): 112–118 [译自: 微生物学通报]  相似文献   

16.
Many kinds of diterpenoids have been isolated from Rabdosia spp. Some of them have anti-microbial effects, counteract inflammation, and inhibit tumor progression activities. We conducted the present study in order to look for bioactive compounds in the medicinal plant Rabdosia excisa. In this study, five compounds were isolated from R. excisa; they were oridonin, isokamebakaurin, oleanolic acid, ursolic acid, and β-sitosterol. In order to identify the function of the extracts, the activity of antibiotics, antioxidation, and immunity test were carried out against these functions. Prospective results were observed in all of the tested items. Translated from Journal of Northeast Normal University (Natural Sciences), 2005, 37(4): 94–98 [译自: 东北师大学报 (自然科学版)]  相似文献   

17.
β-1,4-galactosyltransferase I (β-1,4-GalT I) plays an important role in the synthesis of the backbone structure of adhesion molecules involved in leukocyte–endothelial cell interaction. The expression of β-1,4-GalT I mRNA increased in primary human endothelial cells after exposure to tumor necrosis factor-α (TNF-α). In the central nervous system (CNS), astrocytes play a pivotal role in immunity as immunocompetent cells by secreting cytokines and inflammatory mediators, there are two types of astrocytes. Type-1 astrocytes can secrete TNF-α when stimulated with Lipopolysaccharide (LPS), while the responses of type-2 astrocytes during inflammation are unknown. So we examined the expression change of β-1,4-GalT I mRNA in type-2 astrocytes after exposure to TNF-α and LPS. Real-time PCR showed that TNF-α or LPS affected β-1,4-GalT I mRNA expression in a time- and dose-dependent manner. RT-PCR analysis revealed that TNFR1 and TNFR2 were present in normal untreated type-2 astrocytes, and that TNF-α, TNFR1 and TNFR2 increased in type-2 astrocytes after exposure to TNF-α or LPS. Immunocytochemistry showed that TNFR1 was expressed in the cytoplasm, nucleus and processes of normal untreated type-2 astrocytes, and distributed mainly in the cytoplasm and processes after exposure to LPS. TNFR2 was mainly expressed in the nucleus of normal untreated type-2 astrocytes, and distributed mainly in the processes of type-2 astrocytes after exposure to LPS. Both anti-TNFR1 and anti-TNFR2 antibodies suppressed β-1,4-GalT I mRNA expression induced by TNF-α or LPS. From these results, we conclude that TNF-α signaling via both TNFR1 and TNFR2 translocated from nucleus to cytoplasm or processes is sufficient to induce β-1,4-GalT I mRNA. In addition, we observed that not only exogenous TNF-α but also TNF-α produced by type-2 astrocytes affected β-1,4-GalT I mRNA production in type-2 astrocytes. These results suggest that an autocrine loop involving TNF-α contributes to the production of β-1,4-GalT I mRNA in response to inflammation. Chunlin Xia is the co-first author.  相似文献   

18.
Three novel Gram-positive, endospore-forming bacteria were isolated from a cold and alkaline environment. Phylogenetic analysis showed that the strains were almost identical, and that they were related to Natronobacillus azotifigens 24KS-1T (95.8% identity), Paraliobacillus quinghaiensis YIM-C158T (95.1%), Paraliobacillus ryukyuensis O15-7T (94.5%), and Halolactibacillus miurensis M23-1T (93.9%). The isolates produced amylase, α-galactosidase, β-galactosidase, and β-glucuronidase, and showed optimal growth at pH 10, at 20°C, and at 2–8% (w/v) NaCl. Major fatty acids were C14:0 (10.6–11.6%), anteiso-C15:0 (25.7–32.7%), C16:1 ω11c (12.2–16.0%), and C16:0 (14.0–20.4%). The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol, and meso-diaminopimelic acid was found in the cell-wall peptidoglycan. The G+C content was 38.4%. DNA–DNA hybridization between strain GCM68T and H. miurensis M23-1T was 32.4%, while hybridization to N. azotifigens 24KS-1T, Amphibacillus tropicus Z-7792T, and Paraliobacillus ryukyuensis O15-7T was below 30%. The phylogenetic analysis and G+C content place strain GCM68T in relation to species belonging to Bacillus rRNA group 1, but phylogenetic and physiologic data combined with chemotaxonomic analyses support our proposal for a new genus, Alkalilactibacillus, gen. nov., with the novel species Alkalilactibacillus ikkensis, sp. nov. (type strain is GCM68T = DSM 19937 = LMG 24405).  相似文献   

19.
Improved methods are described for the detection of G1P-binding proteins (G-proteins) in the protonema of mossFunaria hygrometrica and coleoptiles of corn(Zea mays) and sorghum(Sorghum vulgare). We optimized conditions for the transfer of proteins to nitrocellulose, production of high titer polyclonal anti-Gα (common) antibodies and finally the detection of G-proteins by amplification. In addition to the α-subunit of heterotrimeric G-proteins (M r 41–43 kDa), a small molecular weight class (< 30 kDa) was also detected by anti-Gα (common) antibodies. An easy, reliable and efficient filter assay is also described to quantify the toxin catalyzed ADP-ribosylation. The apparentK m of the NAD has been determined to be approximately 1.5μM for the microsomal fraction of moss. Inclusion of G1P stimulated ADP-ribosylation by 2–27-fold. One to three polypeptides representing the α-subunit of heterotrimeric G-proteins of (Mr 37–43 kDa) were ADP-ribosylated in all three plants. The anti-Gβ (C-terminus) antibody cross-reacted strongly with 39 and 34 kDa polypeptide in moss and corn respectively. By employing improved methods two classes of G-proteins have been shown to be present in three plant species.  相似文献   

20.
The in vitro antimicrobial activity against pathogenic bacteria, yeast, and molds were examined in extracts of the Agave species A. lecheguilla, A. picta, A. scabra and A. lophanta using an agar diffusion technique. The extracts of A. picta produced zones of inhibition of 9–13 mm for E. coli, L. monocytogenes, S. aureus, and V. cholerae, while B. cereus and Y. enterocolitica were not inhibited. The other Agave species did not show any detectable inhibitory activity against the bacteria tested; however, all four Agave sp. were inhibitory against all yeast and molds analyzed as evident by 9–20 mm zones of inhibition. The minimum microbicidal concentration (MMC) of the active extract ranged from 1.8 to 7.0 mg/ml for the sensitive bacteria, and 2.0–3.0 mg/ml for yeast. In the case of molds, the minimum inhibitory concentration (MIC) of the active extracts ranged from 3.0 to 6.0 mg/ml. Together, these data suggest that the Agave sp. analyzed are potential antimicrobial candidates with a broad range of activity.  相似文献   

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