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1.
Stir bar sorptive extraction (SBSE) was applied in head space mode (HS), coupled with GC/MS, to compare the aroma profile of three truffle species. A total of 119 volatile organic compounds (VOCs) were identified from the fruiting bodies, of which 70 were not yet described in truffles and 60 in fungi. VOCs profile showed a high intra- and inter-specific variability, with alcohols and sulfur compounds dominating the HS of Tuber borchii and, alcohols, aldehydes and aromatic compounds the HS of T. melanosporum and T. indicum. Despite these variations, eight VOCs markers could be identified allowing the discrimination of the three species. Additionally, T. borchii and T. melanosporum both distinguished themselves from T. indicum due to higher aroma content and larger variety of sulfur containing compounds. Mycelial VOCs production was also investigated under two cultural conditions and led to the identification of eight VOCs. On one side, seven of them were also detected in the fruiting body, confirming their mycelial origin. On the other side, the total absence of some class of compounds (i.e. sulfur) in the mycelium raises questions about their origins in the fruiting bodies and confirms deep metabolic changes between the reproductive (fruiting body) and vegetative (mycelium) stages.  相似文献   

2.
A method for analysis of volatile organic compounds (VOCs) from microbial cultures was established using proton transfer reaction-mass spectrometry (PTR-MS). A newly developed sampling system was coupled to a PTR-MS instrument to allow on-line monitoring of VOCs in the dynamic headspaces of microbial cultures. The novel PTR-MS method was evaluated for four reference organisms: Escherichia coli, Shigella flexneri, Salmonella enterica, and Candida tropicalis. Headspace VOCs in sampling bottles containing actively growing cultures and uninoculated culture medium controls were sequentially analyzed by PTR-MS. Characteristic marker ions were found for certain microbial cultures: C. tropicalis could be identified by several unique markers compared with the other three organisms, and E. coli and S. enterica were distinguishable from each other and from S. flexneri by specific marker ions, demonstrating the potential of this method to differentiate between even closely related microorganisms. Although the temporal profiles of some VOCs were similar to the growth dynamics of the microbial cultures, most VOCs showed a different temporal profile, characterized by constant or decreasing VOC levels or by single or multiple peaks over 24 h of incubation. These findings strongly indicate that the temporal evolution of VOC emissions during growth must be considered if characterization or differentiation based on microbial VOC emissions is attempted. Our study may help to establish the analysis of VOCs by on-line PTR-MS as a routine method in microbiology and as a tool for monitoring environmental and biotechnological processes.  相似文献   

3.
Catharanthus roseus (L.) G. Don cell suspension cultures were used to transform 3b-hydroxyandrost-5-en-17-one, the products were isolated by chromatographic methods. Their structures were established by means of NMR and MS spectral analyses. Nine metabolites were respectively elucidated as: androst-4-ene-3,17-dione (Ⅰ), 6a-hydroxyandrost-4-ene-3,17-dione (Ⅱ), 6a,17b-dihydroxyandrost-4-en-3-one (Ⅲ), 6b-hydroxyandrost-4-ene-3,17-dione (Ⅳ), 17b-hydroxyandrost-4-en-3-one (Ⅴ), 15a,17b-dihydroxyandrost-4-en-3-one (Ⅵ), 15b,17b-dihydroxyandrost-4-en-3-one (Ⅶ), 14a-hydroxyandrost-4-ene-3,17-dione (Ⅷ), 17b-hydroxyandrost-4-ene-3,16-dione (Ⅸ). It is the first time to obtain the above compounds by biotransformation with Catharanthus roseus cell cultures.  相似文献   

4.
Many microorganisms produce volatile organic compounds (VOCs) with biological effects on plants. In this study, Arabidopsis seeds or 14-day-old vegetative plants were exposed to 0.5 μg/l of chemical standards of 26 VOCs previously identified from the biocontrol fungus Trichoderma. Seven compounds (1-decene, 2-heptylfuran, 2-methyl-1-propanol, 2-methyl-1-butanol, 3-methyl-1- butanol, 2-heptanone, and 1-octen-3-ol) were further tested at the physiological concentration (10 ng/l) and 3-methyl-1-butanol, 1-decene, and 2-heptylfuran induced significant increases in fresh weight and total chlorophyll content. Plants exposed to 1-decene had the greatest increase in plant fresh shoot weight (38.9%) and chlorophyll content (67.8%). An RNA sequencing analysis was performed on plants treated with vapors of 1-decene. The expression of 123 genes was differentially affected, encompassing genes involved in cell wall modification, auxin induction, stress, and defense responses, with several major classes of stress-related genes showing down-regulation. To our knowledge, this is the first report of the effect of a plant growth promoting VOC on gene expression in Arabidopsis thaliana. As the role of fungal VOCs in biocontrol moves from correlative studies to more hypothesis driven approaches, our findings can guide both basic and applied studies in agricultural research.  相似文献   

5.
在我国河北省保定市采集到稀有地下真菌地菇状马蒂菌Mattirolomyces terfezioides新鲜子囊果。子囊果个体较大,直径可达10 cm,不规则球状或块状,白色或乳白色,表面有浅开裂,基部有长柄或无。产孢组织中实,成熟时黄褐色。子囊典型的8个孢子;孢子球形,无色至淡黄色,表面具有钝刺,基部连接形成不规则网纹。可能与桃树共生。地菇状马蒂菌子囊果含有丰富的C8挥发性化合物,主要是3-辛酮,1-辛烯-3-醇和3-辛醇(共占总挥发性成分含量的75%左右),少量含硫化合物被检测到。该研究为地菇状马蒂菌在我国的分布提供了新的证据和标本记录,首次分析了其挥发性物质的组成,为地下真菌资源的保护、开发和利用提供新的资源和数据支持。  相似文献   

6.
Summary Production of of 3-acetyldeoxynivalenol (3-ADN) by Fusarium graminearum R 2118 in submerged cultures was characterized for five different media. Toxin production was examined as a function of mycelial growth, sugar utilization, pH and phosphate concentration. In submerged cultures, 3-ADN appeared after 2 days of incubation at 25°C when mycelial growth had slowed down and the pH of the media had dropped to 4.5 or lower. A two stage process was developed for high and rapid production of 3-ADN, in which the biosynthetically active mycelium was grown in a yeast extract-peptone-sucrose medium and the toxin was produced by the mycelium in a sucrose containing minimal medium. Yields of 90–110 mg/l were obtained within 5 days in the production medium. Acidity (low pH) and low phosphate concentration in the minimal medium were both required for 3-ADN production, representing two independent regulating factors for the 3-ADN biosynthesis.  相似文献   

7.
Biogenic volatile organic compounds (VOCs), such as isoprene and alpha-/beta-pinene, are photo-oxidized in the atmosphere to non-volatile species resulting in secondary organic aerosol (SOA). The goal of this study was to examine time trends and diel variations of oxidation products of isoprene and alpha-/beta-pinene in order to investigate whether they are linked with meteorological parameters or trace gases. Separate day-night aerosol samples (PM(1)) were collected in a Scots pine dominated forest in southern Finland during 28 July-11 August 2005 and analyzed with gas chromatography/mass spectrometry (GC/MS). In addition, inorganic trace gases (SO(2), CO, NO(x), and O(3)), meteorological parameters, and the particle number concentration were monitored. The median total concentration of terpenoic acids (i.e., pinic acid, norpinic acid, and two novel compounds, 3-hydroxyglutaric acid and 2-hydroxy-4-isopropyladipic acid) was 65 ng m(-3), while that of isoprene oxidation products (i.e., 2-methyltetrols and C(5) alkene triols) was 17.2 ng m(-3). The 2-methyltetrols exhibited day/night variations with maxima during day-time, while alpha-/beta-pinene oxidation products did not show any diel variation. The sampling period was marked by a relatively high condensation sink, caused by pre-existing aerosol particles, and no nucleation events. In general, the concentration trends of the SOA compounds reflected those of the inorganic trace gases, meteorological parameters, and condensation sink. Both the isoprene and alpha-/beta-pinene SOA products were strongly influenced by SO(2), which is consistent with earlier reports that acidity plays a role in SOA formation. The results support previous proposals that oxygenated VOCs contribute to particle growth processes above boreal forest.  相似文献   

8.
Biodegradation of volatile organic compounds by five fungal species   总被引:4,自引:0,他引:4  
Five fungal species, Cladosporium resinae (ATCC 34066), Cladosporium sphaerospermum (ATCC 200384), Exophiala lecanii-corni (CBS 102400), Mucor rouxii (ATCC 44260), and Phanerochaete chrysosporium (ATCC 24725), were tested for their ability to degrade nine compounds commonly found in industrial off-gas emissions. Fungal cultures inoculated on ceramic support media were provided with volatile organic compounds (VOCs) via the vapor phase as their sole carbon and energy sources. Compounds tested included aromatic hydrocarbons (benzene, ethylbenzene, toluene, and styrene), ketones (methyl ethyl ketone, methyl isobutyl ketone, and methyl propyl ketone), and organic acids ( n-butyl acetate, ethyl 3-ethoxypropionate). Experiments were conducted using three pH values ranging from 3.5 to 6.5. Fungal ability to degrade each VOC was determined by observing the presence or absence of visible growth on the ceramic support medium during a 30-day test period. Results indicate that E. lecanii-corni and C. sphaerospermum can readily utilize each of the nine VOCs as a sole carbon and energy source. P. chrysosporium was able to degrade all VOCs tested except for styrene under the conditions imposed. C. resinae was able to degrade both organic acids, all of the ketones, and some of the aromatic compounds (ethylbenzene and toluene); however, it was not able to grow utilizing benzene or styrene under the conditions tested. With the VOCs tested, M. rouxiiproduced visible growth only when supplied with n-butyl acetate or ethyl 3-ethoxypropionate. Maximum growth for most fungi was observed at a pH of approximately 5.0. The experimental protocol utilized in these studies is a useful tool for assessing the ability of different fungal species to degrade gas-phase VOCs under conditions expected in a biofilter application.  相似文献   

9.
We have utilized the adenylate cyclase stimulator, cholera toxin, as a tool to test the role of cyclic AMP as a mediator of the effects on bone resorption by the calcium-regulating hormones, parathyroid hormone (PTH) and calcitonin. The effects on bone resorption were studied in an organ culture system using calvarial bones from newborn mice. Cyclic AMP response was assayed in calvarial bone explants and isolated osteoblasts from neonatal mouse calvaria. Cholera toxin caused a dose-dependent cAMP response in calvarial bones, seen at and above approx. 1-3 ng/ml and calculated half-maximal stimulation (EC50) at 18 ng/ml. The stimulatory effect of cholera toxin could be potentiated by the phosphodiesterase inhibitor isobutylmethylxanthine (IBMX, 0.2 mmol/l). Cyclic AMP accumulation in the bones was maximal after 4-6 h, and thereafter declined. However, activation of the adenylate cyclase was irreversible and the total amount (bone + medium) of cAMP produced, in the presence of IBMX (0.2 mmol/l), increased with time, for at least 48 h. In osteoblast-like cells cholera toxin (1 microgram/ml) stimulated the cellular levels of cAMP with a peak after 60-120 min, which could be potentiated with IBMX. The total cAMP accumulation indicated an irreversible response. In short-term bone organ cultures (at most, 24 h) cholera toxin, at and above 3 ng/ml, inhibited the stimulatory effect of PTH (10 nmol/l) on 45Ca release from prelabelled calvarial bones. The inhibitory effect of cholera toxin (0.1 microgram/ml) on 45Ca release was significant after 6 h and the calculated IC50 value at 24 h was 11.2 ng/ml. Cholera toxin (0.1 microgram/ml) also inhibited PTH-stimulated (10 nmol/l) release of Ca2+, inorganic phosphate (Pi), beta-glucuronidase, beta-N-acetylglucosaminidase and degradation of organic matrix (release of 3H from [3H]proline-labelled bones) in 24 h cultures. 45Ca release from bones stimulated by prostaglandin E2 (1 mumol/l) and 1 alpha-hydroxyvitamin D3 (0.1 mumol/l) was also inhibited by cholera toxin (0.3 microgram/ml) in 24-h cultures. The inhibitory effect of cholera toxin on bone resorption was transient, and in long-term cultures (120 h) cholera toxin caused a dose-dependent, delayed stimulation of mineral mobilization (Ca2+, 45Ca, Pi), degradation of matrix and release of the lysosomal enzymes beta-glucuronidase and beta-N-acetylglucosaminidase.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

10.
The objective of this study was to investigate the volatile organic compounds (VOCs) produced from heterotrophic cultivation of the cyanobacterium Phormidium autumnale with different sources of monosaccharides. The volatiles were isolated by headspace solid-phase micro-extraction in different residence times, separated by gas chromatography, and identified by mass spectrometry (SPME-GC/MS). The profile of volatiles contained a total of 44 volatile compounds when P. autumnale was grown heterotrophically on glucose and 35 when grown on fructose. A combined total of 68 compounds was identified and 11 volatiles were common to both extracts. The compound 3-methyl-butanol was identified among the major volatile compounds formed, reaching a concentration of 141.5 μg mg?1 dry weight for the glucose-grown cultures and 69.5 μg mg?1 for the fructose-grown cultures after 144 h. Many of the compounds detected during heterotrophic cultivation originated from terpenoids (β-ionone, β-cyclocitral, and 5,6-epoxy-β-ionone), fatty acids (hexanol, hexanal), or the 2-keto acid pathway (3-methyl-butanol, propanol, butanol).  相似文献   

11.
Two important character-impact compounds of strawberry flavour, the furanones 2,5-dimethyl-4-hydroxy-2H-furan-3-one (DMHF) and 2,5-dimethyl-4-methoxy-2H-furan-3-one (mesifuran) were synthesized by strawberry tissue cultures derived from a cultivated species (Fragaria × ananassa, cv. Elsanta) after these were treated with Methylobacterium extorquens. These flavour compounds were analysed by HPLC-UV and their levels were compared in the treated and control tissues. In Methylobacterium extorquens treated callus cultures DMHF and mesifuran levels were 5.9 and 11.4 μg/g of fresh weight of callus respectively, compared to zero in the untreated ones. When Methylobacterium extorquens was fed with 1,2-propanediol, 2-hydroxy-propanal (lactaldehyde) was formed. This bacterial oxidation of 1,2-propanediol to lactaldehyde linked with the presence of 1,2-propanediol in strawberry suggests that the increased levels of the two furanones in the treated strawberry cultures is the result of Methylobacterium extorquens oxidative activity on 1,2-propanediol and the bioconversion by the plant cells of this oxidation product, lactaldehyde to DMHF and mesifuran. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

12.
Copper and chlorine-releasing compounds were the most fungitoxic of 13 compounds tested in water for inhibition of Phytophthora cinnamomi. Mycelium was killed when immersed for 24 h in suspensions containing copper (13–45 mg/1) or a solution containing free residual chlorine (100 mg/1). Sub-lethal concentrations of these compounds reduced the numbers of sporangia. Exposing zoospores of P. cinnamomi for 60 s to water containing 2 mg free residual chlorine/1 reduced subsequent colony production on agar plates by 96–100%.
Prothiocarb, etridiazole ex. and furalaxyl killed mycelium immersed in solutions or suspensions for 3–6 days at 1500, 1000 and 600 mg a.i./l respectively and suppressed sporangium production at 1000, 500 and 300 mg/1.
Mycelium survived 3 days' immersion in ethyl hydrogen phosphonate compounds at 4000 mg a.i./l but 1000 mg a.i./l suppressed sporangium formation.
1-(2-Cyano-2-methoxyiminoacetyl)-3-ethyl urea and drazoxolon did not kill mycelium at 2000 and 1500 mg a.i./l respectively with a 6-day exposure, but reduced numbers of sporangia produced.  相似文献   

13.
Four new analogs of 28-homocastasterone have been synthesized and completely characterized for the first time from stigmasterol. (22R, 23R,24S)-3beta-acetoxy-22,23-dihydroxy-5alpha-stigmastan+ ++-6-one (17), (22R,23R,24S)-3beta-bromo-22,23-dihydroxy-5alpha-stigmast an-6-one (18), (22R,23R,24S)-3beta-acetoxy-5,22, 23-trihydroxy-5alpha-stigmastan-6-one (20), and (22R,23R, 24S)-3beta-bromo-5,22,23-trihydroxy-5alpha-stigmastan-6-one (21), were obtained through a synthetic route based on regioselective Delta(5) epoxidation. Compounds 17 and 18, bearing a 5alphaH moiety, were prepared through a reductive opening of the 5beta,6beta epoxy precursor, and compounds 20 and 21, analogs with a 5alphaOH moiety were obtained by hydrolytic opening of a mixture of 5alpha,6alpha and 5beta,6beta epoxy precursors. Known compounds 19 and 22 were also obtained following the described synthetic routes, respectively. The new compounds were tested with the traditional auxin-like bioassay for brassinosteroids with 19 and 22 as standards. All compounds were comparatively evaluated for their inhibitory effect on the replication of DNA (HSV-1) virus.  相似文献   

14.
We report in this study large induction of volatile organic compounds (VOCs) from a single inflorescence of mossy sorrel (Rumex confertus Willd., Polygonaceae), by herbivory of the weevil (Hypera rumicis L., Coleoptera: Curculionidae). VOCs blend induced by the weevil herbivory included 1 green leaf volatiles (GLVs) ((Z)‐3‐hexen‐1‐yl acetate), five terpenes ((Z)‐β‐ocimene, linalool, geranyl acetate, β‐caryophyllene and (E)‐β‐farnesene), three esters (benzyl acetate, methyl salicylate and methyl anthranilate) and one aromatic heterocyclic organic compound (indole). Uninjured plants produced only detectable amounts of VOCs. A Y‐tube experiment revealed that both females and males of H. rumicis were not attracted to any of tested concentrations (1, 5, 25, 125 ng/min). Also both females and males were significantly repelled by the highest concentrations (25 and 125 ng/min). Additionally, concentration of 5 ng/min proved to be repellent for females of H. rumicis.  相似文献   

15.
Volatile organic compounds produced by human skin cells   总被引:1,自引:0,他引:1  
Skin produces volatile organic compounds (VOCs) released to the environment with emission patterns characteristic of climatic conditions. It could be thought that these compounds are intermediaries in cell metabolism, since many intermediaries of metabolic pathways have a volatile potential. In this work, using gas chromatography, we answered the question of whether VOC profiles of primary cultures of human dermal fibroblasts were affected by the type of culture conditions. VOCs were determined for different types of culture, finding significant differences between skin cells grown in classical monolayer culture -2D- compared with 3D matrix immobilized cultures. This indicates that VOC profiles could provide information on the physiological state of skin cells or skin.  相似文献   

16.
总状毛霉对4-烯-3-酮甾体的生物转化研究   总被引:6,自引:0,他引:6  
从土样中筛选到一株能转化甾体的菌株,经形态观察,鉴定为总状毛霉(Mucor racemosus)。首次利用该菌株对4-烯-3-酮类甾体衍生物进行生物转化,目的是合成具有潜在活性的羟基类4-烯-3-酮衍生物。转化条件为27℃,220r/min振荡培养4d。转化产物经乙酸乙酯萃取,用硅胶柱层析法分离,通过红外、质谱和核磁分析确定了甾体转化产物的化学结构。黄体酮生物转化得到的产物是14α-羟基-4-孕甾烯-3,20-二酮和7α,14α-二羟基-4-孕甾烯-3,20-二酮;4-雄烯二酮的转化产物是14α-羟基-雄甾-4-烯-3,17-二酮1、4α,17β-二羟基-雄甾-4-烯-3-酮和6α,17β-二羟基-雄甾-4-烯-3-酮。研究结果表明总状毛霉具有转化甾体的能力,对4-烯-3-酮类甾体进行生物转化的主要产物是14α-羟基甾体衍生物。  相似文献   

17.
AIMS: To examine and illustrate the morphological characteristics and growth kinetics of Cs-HK1, a Tolypocladium fungus, isolated from wild Cordyceps sinensis in solid and liquid cultures, and the major chemical constituents and antitumour effects of Cs-HK1 mycelium. METHODS AND RESULTS: The Cs-HK1 fungus was isolated from the fruiting body of a wild C. sinensis and identified as a Tolypocladium sp. fungus. It grew rapidly at 22-25 degrees C on a liquid medium containing glucose, yeast extract, peptone and major inorganic salts, with a specific growth rate of 1.1 day(-1), reaching a cell density of 23.0 g dw l(-1) in 7-9 days. Exopolysaccharides accumulated in the liquid culture to about 0.3 g l(-1) glucose equivalent. In comparison with natural C. sinensis, the fungal mycelium had similar contents of protein (11.7-microg) and carbohydrate (654.6-microg) but much higher contents of polysaccharide (244.2 mg vs 129.5 mg), adenosine (1116.8-microg vs 264.6 microg) and cordycepin (65.7 microg vs 20.8 microg) (per gram dry weight). Cyclosporin A, an antibiotic commonly produced by Tolypocladium sp., was also detected from the mycelium extract. The hot water extract of mycelium showed low cytotoxic effect on B16 melanoma cells in culture (about 25% inhibition) but significant antitumour effect in animal tests, causing 50% inhibition of B16 cell-induced tumour growth in mice. CONCLUSIONS: The Tolypocladium sp. fungus, Cs-HK1, can be easily cultivated by liquid fermentation. The mycelium biomass contained the major bioactive compounds of C. sinensis, and the mycelium extract had significant antitumour activity. SIGNIFICANCE AND IMPACT OF THE STUDY: The Cs-HK1 fungus may be a new and promising medicinal fungus and an effective and economical substitute of the wild C. sinensis for health care.  相似文献   

18.
Secondary metabolites from the cultures of the dark septate fungal endophyte (DSE) Drechslera sp., isolated from the roots of rye grass (Lollium sp.) and cultured under different experimental conditions, are described here for the first time. The use of suberoylanilidehydroxamic acid (SAHA) and other histone deacetylase inhibitors as epigenetic modifiers in the culture medium was evaluated by LC/MS and LC/MS/MS. Several differences in the metabolite production were detected by means of supervised principal component analysis (PCA) of LC/MS data. The presence of the compounds in the culture medium or in the mycelium was compared. In order to confirm their structure, many of these natural products were isolated from a larger scale culture. These metabolites were characterized as prenylhydroxybenzoic acids and chromans, two compounds, one of each class were previously undescribed, prenylquinoids, diketopiperazines and macrosphelides. Some of the compounds, which were released to the medium, showed good antifungal activity, suggesting that these compounds could protect Lollium from fungal phytopatogens. The use of SAHA as an additive of the cultures also induced the release of hexosylphytosphyngosine to the culture medium. The biotransformation of the inhibitors was observed in addition to the production of antifungal metabolites, showing the ability of this endophytic strain to control xenobiotics.  相似文献   

19.
Synthesis of some novel biologically active piperidin-4-one oxime carbonates from 1-methyl-3alkyl-2,6-diphenylpiperidin-4-one oximes and substituted chloroformates was carried out in the presence of potassium carbonate as base and tetrabutylammonium bromide (TBAB) as catalyst. The newly synthesized compounds were characterized by IR, 1H, 13C NMR and LC–mass spectra. Based on the 1H NMR analysis, all the compounds were found to adopt normal chair conformation with equatorial orientation of all the substituents. For all the synthesized compounds (5a5l) antimicrobial activity has been tested against bacterial and fungal strains using Streptomycin and Amphotericin B as standards.  相似文献   

20.
Production and purification of statins from Aspergillus terreus strains   总被引:3,自引:0,他引:3  
Lovastatin, mevastatin, pravastatin and monacolin J were produced using Aspergillus terreus strains. Mevastatin (170 mg/l) was obtained at 14 days from the A1 strain, lovastatin (256 mg/l) at 21 days from the A2 strain and pravastatin (270-300 mg/l) at 14 days from both the A1 and A2 strains grown on defatted soybean flour. Similar yields of monacolin J (5-10 mg/l) were detected for both strains. Fermentation carried out by adding glycerol to A1 7-d old cultures gave 244 mg lovastatin/l at 14 days employing whole soybean flour. A new extraction procedure was applied to an A2 19-d old culture on the mycelium and the culture filtrate separately. Recovery yield showed that 83% lovastatin was associated with the mycelium and 17% was free in the culture filtrate. © Rapid Science Ltd. 1998  相似文献   

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