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1.
An unidentified styrene trimer (ST) isolated from the acetonitrile extract of polystyrene (PS) food containers was characterized as (1S*,6R*,7S*,8S*,11R*)-6,11-diphenyltricyclo[6,2,2,0(2,7)]dodeca-2,9-diene. The content and migration of this compound in PS food containers were determined by GC-MS (SIM). Furthermore, an endocrine-disrupting effect was tested using in vitro and in vivo assays of the compound. In conclusion, it seems that the compound does not present the effect.  相似文献   

2.
Biotransformation of a monoterpene ketone, (R)-(+)-pulegone (I), a potent hepatotoxin, was studied using a fungal strain, Mucor piriformis. Eight metabolites, namely, 5-hydroxypulegone (II), piperitenone (III), 6-hydroxypulegone (IV), 3-hydroxypulegone (V), 5-methyl-2-(1-hydroxy-1-methylethyl)-2-cyclohexene-1-one (VI), 3-hydroxyisopulegone (VII), 7-hydroxypiperitenone (VIII), and 7-hydroxypulegone (IX), have been isolated from the fermentation medium and identified. GC analysis of the metabolites indicated that II was the major metabolite formed. The organism initiates transformation either by hydroxylation at the C-5 position or by hydroxylation of the ring methylenes, the former being the major activity. On the basis of the identification of the metabolites, pathways for the biotransformation of (R)-(+)-pulegone have been proposed. The mode of transformation of (S)-(-)-pulegone by this organism was shown to be similar to that of its (R)-(+)-enantiomer. When isopulegone (X) was used as the substrate, the organism isomerized it to pulegone (I), which was then transformed to metabolites II-IX.  相似文献   

3.
Stagonospora cirsii is a pathogen of Cirsium arvense, causing necrotic lesions on leaves of this noxious weed. The fungus produced toxic metabolites when grown in liquid culture. A new phytotoxin, named stagonolide, was isolated and characterized as (8R,9R)-8-hydroxy-7-oxo-9-propyl-5-nonen-9-olide by spectroscopic methods. Stagonolide was shown to be a nonhost-specific but selective phytotoxin. Leaves of C. arvense were most sensitive and leaves of tomato and pepper (both Solanaceae) were less sensitive to stagonolide, which was assayed at 5 x 10(-3) M, than other plants. Stagonolide assayed at 5 x 10(-6) M was demonstrated to be a strong inhibitor of root growth in seedlings of C. arvense and some other Asteraceae species. Seedlings growth in wheat and radish was much less affected by the toxin, and seedlings of cucumber were insensitive to it.  相似文献   

4.
A strain of Botrytis fabae isolated from faba bean (Vicia faba L.) plants displaying clear chocolate spot disease symptoms produced phytotoxic metabolites in vitro. The phytotoxins isolated from the culture filtrate organic extract were characterized by spectroscopic and optical methods. A new naphthalenone pentaketide, named botrytone, was isolated and characterized as (4R)-3,4-dihydro-4,5,8-trihydroxy-1(2H)-naphthalenone together with other well-known closely related naphthalenones such as regiolone and cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-ones. When tested on leaves of the host plant, with the cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-ones assayed in mixture, regiolone demonstrated the highest level of phytotoxicity together with cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-ones. Botrytone showed moderate phytotoxic activity at 1 mg/mL and was still phytotoxic at 0.5 mg/mL.  相似文献   

5.
Many edible plant metabolites are known to be useful as cellular antioxidants. In the search for antioxidative chemicals from native fruits of the Campania region of Italy, Prunus cerasus L., an acidic cherry widely used for culinary purposes, has been studied. Fruit crude extracts (MeOH, EtOAc, and hexane) were submitted to an antioxidative screening using specific assay media characterized from the presence of highly reactive radical species (DPPH*, ABTS*+, O2*-, NO) or lipoperoxidation markers. The reducing power of the samples was also determined. It was observed that the most polar extracts in MeOH and EtOAc were able to exercise a massive and dose-increasing antioxidative capacity. The peculiar efficacy of the same extracts was revealed by investigating their protein and deoxyribose oxidation capacity. A preliminary analysis of total phenol, flavonoid, and anthocyanin contents together with biological screening data put the basis on P. cerasus fruit phytochemical investigation of methanolic extract. Twenty secondary metabolites were isolated and characterized by spectroscopic (especially 1D and 2D NMR) and spectrometric techniques. 1-(4-Hydroxyphenyl)-1,2-ethanediol-1,2-bis-1-O-beta-D-glucopyranoside (3), (4-hydroxy-3-methoxyphenyl)methanol-1-O-beta-D-gentiobioside (4), epicatechin-3-malate (14), and epicatechin-3-(1'-methyl)malate (15) were isolated for the first time. All of the compounds were evaluated for their radical scavenging activity on DPPH*, O2*-, and NO. Flavonoids and quinic acid derivatives were found to be the more antioxidative substances.  相似文献   

6.
Protein changes for four hard red spring wheat genotypes (Len, Marshall, 215, and Butte 86) were assessed at various stages of breadmaking using a size-exclusion HPLC technique. Breadmaking stages considered were flour, after mixing, before punching, after punching, after fermentation, and after proofing. Quality and functional characteristics of the four wheat genotypes were determined. The three main protein groups isolated by SE-HPLC were further characterized by SDS-PAGE. A direct relationship between polymeric glutenin (peak I of SE-HPLC fractions) in flours and loaf volume was found for the three wheat genotypes with identical high molecular weight glutenin subunit (HMW-GS) composition (2*, 7+9, 5+10) and one line with similar HMW-GS composition (2*, 7+9, 2+12), differing in the Glu-D1 locus. Quantitative changes in the distribution of SDS-soluble proteins fractionated by SE-HPLC were also examined. Peak I proteins (polymeric proteins) from SDS-extractable proteins tend to decrease during breadmaking, while peak III proteins (low molecular weight) tend to increase. Peak II (monomeric proteins, medium molecular weight) did not show a change in quantity during breadmaking. These results seem to indicate that some type of rearrangement took place during the breadmaking process to release proteins of smaller molecular weight.  相似文献   

7.
Four new abscisic acid related compounds (1-4), together with (+)-abscisic acid (5), (+)-beta-D-glucopyranosyl abscisate (6), (6S,9R)-roseoside (7), and two lignan glucosides ((+)-pinoresinol mono-beta-D-glucopyranoside (8) and 3-(beta-D-glucopyranosyloxymethyl)-2- (4-hydroxy-3-methoxyphenyl)-5-(3-hydroxypropyl)-7-methoxy-(2R,3S)-dihydrobenzofuran (9)) were isolated from the antioxidative ethanol extract of prunes (Prunus domestica L.). The structures of 1-4 were elucidated on the basis of NMR and MS spectrometric data to be rel-5-(3S,8S-dihydroxy-1R,5S-dimethyl-7-oxa-6-oxobicyclo[3,2,1]oct-8-yl)-3-methyl-2Z,4E-pentadienoic acid (1), rel-5-(3S,8S-dihydroxy-1R,5S-dimethyl-7-oxa-6-oxobicyclo[3,2,1]oct-8-yl)-3-methyl-2Z,4E-pentadienoic acid 3'-O-beta-d-glucopyranoside (2), rel-5-(1R,5S-dimethyl-3R,4R,8S-trihydroxy-7-oxa-6-oxobicyclo[3,2,1]oct-8-yl)-3-methyl-2Z,4E-pentadienoic acid (3), and rel-5-(1R,5S-dimethyl-3R,4R,8S-trihydroxy-7-oxabicyclo[3,2,1]- oct-8-yl)-3-methyl-2Z,4E-pentadienoic acid (4). The antioxidant activities of these isolated compounds were evaluated on the basis of oxygen radical absorbance capacity (ORAC). The ORAC values of abscisic acid related compounds (1-7) were very low. Two lignans (8 and 9) were more effective antioxidants whose ORAC values were 1.09 and 2.33 micromol of Trolox equiv/micromol, respectively.  相似文献   

8.
Twenty-five compounds were identified from the dichloromethane and methanol extracts of royal jelly from Greece. Among them, 16 compounds are reported for the first time as royal jelly constituents, whereas 7 of them are isolated for the first time as natural products. The 7 new compounds were fatty acid derivatives: 10-acetoxydecanoic acid (1), trans-10-acetoxydec-2-enoic acid (2), 11-oxododecanoic acid (3), (11S)-hydroxydodecanoic acid (4), (10R,11R)-dihydroxydodecanoic acid (5), 3,11-dihydroxydodecanoic acid (6), and (11S),12-dihydroxydodecanoic acid (7). The structures of the isolated compounds were determined by spectroscopic methods, mainly by the concerted application of 1D and 2D NMR techniques (HMQC, HMBC) and mass spectrometry. The studied sample and the isolated compounds were tested for their antimicrobial activity against Gram-positive and Gram-negative bacteria and fungi and exhibited interesting activities.  相似文献   

9.
The supply of cadmium from soil to plant roots mainly depends on the diffusion prooess.This work was conducted to study the effects of some soil properties on cadmium diffusion coefficient (D) in soil. Measurements were made using the Shofield and Graham-Bryce‘s isotopic labelling method.Cadmium diffusion coefficients varied from 10^-7to 10^-9 cms^2-1.Higher values were observed in acid sandy soils and lower values in calcareous clay soils.Liming an acid soil resulted in a substantial decrease of D.Addition of cadmium as nitrate salt generally increased D,while addition of sewage sludge and organic matter resulted in a significant decrease of cadmium diffusion.The rhizospheric activity also induced a moderate reduction in D.The relationships between D(10^-9cms^2-1)on the on hand and soil pH.moisture(Mc,g kg^-1) ,organic matter(OM,g kg^-1),clay(Cy,gkg^-1)and cadmium content(Cd,mgkg^-1) on the other were obtained by the multiple regression:D=182.1-29.91pH 0.210Mc-0.303OM 0.011Cy 1.64Cd(R^2=0.859,n=22).  相似文献   

10.
Microorganisms capable of degrading carbofuran were isolated from soils and examined for the degradation of this pesticide at ring structure. An isolate that could degrade carbofuran and carbofuran-7-phenol was selected for further studies. The 16S rRNA analysis results showed that the isolate belongs to the genus of Sphingomonas, close to dioxin and dicamba degraders, and is named Sphingomonas sp. SB5. SB5 did not show any similarity of 16S rRNA to known carbofuran degraders. When time-course degradation of carbofuran by SB5 was examined by solvent extraction combined with liquid chromatographic analysis, almost complete disappearance of carbofuran was observed within 12 h, giving several accumulative metabolites. Bacterial cultures incubated with carbofuran-7-phenol suggested that the accumulated metabolites were derived from carbofuran-7-phenol. The control without SB5 and kanamycin-treated SB5 did not show any metabolite, suggesting a biological involvement in the degradation of carbofuran. GC/MS and LC/MS analyses identified 2-hydroxy-3-(3-methylpropan-2-ol) phenol as one of the accumulated metabolites, suggesting that the strain SB5 could degrade carbofuran-7-phenol by hydrolysis at the furanyl ring. This is the first report to identify 2-hydroxy-3-(3-methylpropan-2-ol) phenol as a new product derived biologically from carbofuran-7-phenol.  相似文献   

11.
New dammarane-type saponins from the galls of Sapindus mukorossi   总被引:2,自引:0,他引:2  
Five new dammarane-type saponins, 3beta,7beta,20(S),22-tetrahydroxydammar-24-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 3beta,7beta,20(S),22,23-pentahydroxydammar-24-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 3beta,7beta,20(S),22,25-pentahydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, 25-methoxy-3beta,7beta,20(S),22-tetrahydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, and 25-methoxy-3beta,7beta,20(R)-trihydroxydammar-23-ene-3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside, named sapinmusaponins A (1), B (2), C (3), D (4), and E (5), respectively, together with three known phenylpropanoid glycosides (6-8), were isolated from the galls of Sapindus mukorossi. The structures of these saponins were elucidated on the basis of spectroscopic analyses and chemical methods. Preliminary bioassay data revealed that saponins 1 and 3-5 showed moderate cytotoxic activity (ED50 approximately 9-18 microg/mL) against human tumor cell lines (Hepa59T/VGH, NCI, HeLa, and Med) and that 1-5 were inactive in vitro against HIV replication in H9 lymphocytes.  相似文献   

12.
The vapor-phase toxicity of Derris scandens Benth.-derived constituents was evaluated against four stored-product pests ( Callosobruchus chinensis L., Sitophilus oryzae L., Rhyzopertha dominica L., and Tribolium castaneum H.) using fumigation bioassays and compared to those of commonly used insecticides. The structures of all constituents of were characterized by spectroscopic analyses [nuclear magnetic resonance (NMR) and mass spectrometry]. The sensitivity of the test insect to compounds varied with exposure time, concentration, and insect species. Over 100% mortality after 24 h was achieved with the compounds osajin (2), scandinone (5), sphaerobioside (8), and genistein (9) against all of the test insects, while laxifolin (3) and lupalbigenin (4) showed 100% mortality after 72 h against T. csataneum and R. dominica . Scandenone (1), scandenin A (6), and scandenin (7) were less effective. Among the insects, C. chinensis , S. oryzae , and R. dominica were more susceptible to the treatments, whereas T. castaneum was less susceptible. The results of fumigation tests indicated that compounds from D. scandens whole plant extract are potential candidates to control stored-product pests.  相似文献   

13.
新疆小麦地方品种资源HMW-GS的遗传多样性组成分析   总被引:2,自引:0,他引:2  
为了明确新疆小麦地方品种高分子量麦谷蛋白亚基的遗传多样性,并为小麦品质改良提供基础材料,利用十二烷基硫酸钠聚丙烯酰胺凝胶电泳(SDS-PAGE) 技术,分析了源自新疆地区的282份小麦地方品种的高分子量麦谷蛋白亚基组成。结果表明,在Glu-A1、Glu-B1和Glu-D1位点上的等位变异分别为3、6和 5种,三个位点上的优势亚基依次为null、7+8和2+12,其频率分别是75.5%、90.8%和72.0%。在Glu-1位点共检测到20种亚基组合,其中(null, 7+8, 2+12)组合的频率最高,为52.8%, 其次是(null, 7+8, 2.6+12)和(2*, 7+8, 2+12)组合,其频率分别为14.1%和11.0%,其它亚基组合的频率均低于10%。另外,在Glu-D1位点上还检测到一个新的亚基2.6+12。在供试的282份新疆地方品种中发现了两份具有优质亚基组合的材料,它们的亚基组成为(2*, 7+9, 5+10)和(1, 7+9, 5+10),这些地方品种可作为改良小麦品质性状的重要遗传资源。  相似文献   

14.
Two new piperidine amides, N-[(2E,4E,8Z)-tetradecatrienoyl]piperidine (1) and N-[(2E,4E,8Z,11Z)-tetradecatetrenoyl]piperidine (2), along with the known metabolites N-[(2E,4E)-tetradecadienoyl]piperidine (3), N-isobutyl-(2E,4E,)-tetradecadienamide (4), N-isobutyl-(2E,4E,8Z)-tetradecatrienamide (5), N-isobutyl-(2E,4E,8Z,11Z)-tetradecatetraenamide (6), sesamine (7), pinoresinol (8), and espeletone (9), were isolated from the dichloromethane/methanol extracts of the plant Otanthus maritimus Hoffman & Link collected from coastal areas in Greece. Pinoresinol (8) and espeletone (9) are reported for the first time as metabolites of O. maritimus. The structures of the new natural products were elucidated by interpretation of their NMR and high-resolution mass spectral measurements. The insecticidal properties of the crude extracts, essential oil, and isolated metabolites 1-9 were evaluated on Crematogaster scutellaris (Olivier) ants and Reticulitermes balkanensis (Clement) termites, showing significant levels of activity.  相似文献   

15.
Biological effects on Tribolium castaneum larvae were evaluated for three withanolides isolated from Salpichroa origanifolia (Solanaceae), (20S,22R,24S,25S,26R)-5alpha,6alpha:22,26:24,25-triepoxy-26-hydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide A, 1), (20S,22R,24S,25S,26R)-22,26:24,25-diepoxy-5alpha,6beta,26-trihydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide C, 2), and (20S,22R,24S,25S,26R)-5alpha,6alpha:22,26:24,25-triepoxy-15,26-dihydroxy-17(13-->18)-abeo-ergosta-2,13,15,17-tetraen-1-one (salpichrolide G, 3), and for several chemically modified analogues. The compounds were incorporated into the larval diet at concentrations of 500 and 2000 ppm. Salpichrolide C (2) produced a significant delay in the development of neonate larvae to adults at the highest concentration (2000 ppm); development delays and lethal effects were produced by salpichrolides A (1) and G (3) at both concentrations assayed. The size of surviving adults was used as a criterion for assessing feedant deterrent effects; the results suggest that these compounds act as feeding inhibitors. Influence of chemical modifications in development delay was analyzed.  相似文献   

16.
Five winter wheat cultivars--GK Othalom (HMW-GS composition 2*, 7+8, 5+10), Ukrainka (1, 7+8, 5+10), Palotás (2*, 7+9, 5+10), K?dm?n (2*, 7+8, 5+10), and Csongrád (2*, 7+9, 2+12)--grown in Hungary and harvested in the year 2005 were studied. The biosynthesis of gluten-forming polypeptides was followed starting at the 12th day after anthesis to the 53rd. Fresh kernel weight, moisture, and dry matter content of fresh kernels and gliadin and glutenin contents were determined. Gliadin components, total amounts of HMW and LMW polypeptides, and individual HMW polypeptides were determined using a RP-HPLC technique. Although considerable quantitative differences were observed concerning the content of total protein, gliadin, glutenin, and individual gluten-forming polypeptides, the character of accumulation of protein components--determined on the basis protein mass/kernel--was the same for the all of the cultivars studied and could be presented by a sigmoid curve. Small quantities of the gliadin and glutenin monomers may be detected in early stages of kernel development, but the bulk of these proteins is synthesized in later stages of development. It is generally suggested by specialists that the formation and accumulation of glutenin polymers starts later than the synthesis of monomers. Experimental data presented in this paper confirm this suggestion and show that in the first phase of protein synthesis the monomers are in "free" form; polymeric glutenin is detected only later. HMW glutenin subunits are synthesized synchronously, and quantitatively the polypeptides coded by chromosomes D and B dominate.  相似文献   

17.
With the aid of multilayer coil countercurrent chromatography, subsequent acetylation, and liquid chromatographic purification of a glycosidic mixture obtained from lulo (Solanum quitoense L.) leaves, three C(13)-norisoprenoid glucoconjugates were isolated in pure form. Their structures were elucidated by NMR, MS, and CD analyses to be the novel (6R,9R)-13-hydroxy-3-oxo-alpha-ionol 9-O-beta-D-glucopyranoside (4a), the uncommon (3S,5R,8R)-3, 5-dihydroxy-6,7-megastigmadien-9-one 5-O-beta-D-glucopyranoside (citroside A) (5a), and the known (6S,9R)-vomifoliol 9-O-beta-D-glucopyranoside (6a). Enzymatic treatment of compound 5a showed the formation of 3-hydroxy-7,8-didehydro-beta-ionone (7), an important lulo peeling volatile, which in its turn after chemical reduction and heated acid catalyzed rearrangement generates beta-damascenone (9) and 3-hydroxy-beta-damascone (10).  相似文献   

18.
Bisphenol A [2,2-bis(4-hydroxyphenyl)propane] (BPA) is a widely used industrial chemical resulting in occupational and consumer exposure. BPA possesses weak estrogenomimetic activity and can be cytotoxic, though the underlying mechanisms of its toxicity toward cells are not completely understood. The metabolism of BPA by CD1 mice liver microsomal and S9 fractions was investigated. Nine metabolites were isolated and characterized using HPLC and mass spectrometry. Many of these metabolites were characterized for the first time in mammals, namely isopropyl-hydroxyphenol (produced by the cleavage of BPA), a bisphenol A glutathione conjugate, glutathionyl-phenol, glutathionyl 4-isopropylphenol, and BPA dimers. Most of these metabolites apparently share a common metabolic pathway, for which considerable evidence supports the hypothesis of the production of a reactive intermediate, and also helps explain BPA cytotoxicity.  相似文献   

19.
Antioxidant compounds from the leaves of Peucedanum japonicum thunb   总被引:1,自引:0,他引:1  
Seventeen compounds were isolated from the n-butanol soluble fraction of the leaves of Peucedanum japonicum Thunb. On the basis of MS and various NMR spectroscopic techniques, the structures of the isolated compounds were determined as isoquercitrin (1), rutin (2), 3-O-caffeoylquinic acid (3), 4-O-caffeoylquinic acid (4), 5-O-caffeoylquinic acid (5), cnidioside A (6), praeroside II (7), praeroside III (8), apterin (9), esculin (10), (R)-peucedanol (11), (R)-peucedanol 7-O-beta-d-glucopyranoside (12), l-tryptophan (13), uracil (14), guanosine (15), uridine (16), and thymidine (17). All compounds except 11 and 12 were isolated for the first time from P. japonicum. Several isolated compounds were quantified by high-performance liquid chromatography analysis. In addition, all isolated compounds were examined for radical scavenging on 1,1-diphenyl-2-picrylhydrazyl radical and for inhibition of oxidation of liposome induced by 2,2'-azobis(2-amidinopropane)dihydrochloride. Compounds 2-5 were found to be the major potent constituents, which contribute to the antioxidant activity of P. japonicum leaves.  相似文献   

20.
In organic apple orcharding there is a continuous need for natural fungicides effective against Venturia inaequalis (Cooke) Winter, the causal agent of apple scab. In this study an in vitro assay is presented for determining the germination inhibitory potential of extracts and pure compounds. From a screening of plant extracts, the methanol extract of Morus root bark revealed distinct V. inaequalis inhibiting qualities, which were subjected to a bioguided fractionation. Among the isolated metabolites [moracins M (1), O/P (2), kuwanon L (3), and sanggenons D (4), B (5), G (6), O (7), E (8), and C (9)] all the Diels-Alder adducts (3-9) showed an antifungal activity with IC50 values between 10 and 123 microM. The in vitro activity of the most active fraction (A5, IC50 39.0 +/- 4.2 microg/mL) was evaluated in vivo, confirming a distinct antifungal activity against V. inaequalis for the tested natural material.  相似文献   

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