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ABSTRACT: The endophytic fungus Hyalodendriella sp. Ponipodef12 was isolated from the hybrid 'Neva' of Populus deltoides Marsh × P. nigra L. In this study, four benzopyranones were isolated from the ethyl acetate extract of Hyalodendriella sp. Ponipodef12, and identified as palmariol B ( 1 ), 4-hydroxymellein ( 2 ), alternariol 9-methyl ether ( 3 ), and botrallin ( 4 ) by means of physicochemical and spectroscopic analysis. All the compounds were evaluated for their antibacterial, antifungal, antinematodal and acetylcholinesterase inhibitory activities. 4-Hydroxymellein ( 2 ) exhibited stronger antibacterial activity than the other compounds. Palmariol B ( 1 ) showed stronger antimicrobial, antinematodal and acetylcholinesterase inhibitory activities than alternariol 9-methyl ether ( 3 ) which indicated that the chlorine substitution at position 2 may contribute to its bioactivity. The results indicate the potential of this endophytic fungus as a source of bioactive benzopyranones.
Molecules 01/2012; 17(10):11303-14. · 2.39 Impact Factor
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ABSTRACT: Halimodendron halodendron has been used as forage in northwestern China for a long time. Its young leaves and flowers are edible and favored by indigenous people. In this study, eleven phenolic compounds were bioassay-guided and isolated from the aerial parts of H. halodendron for the first time. They were identified by means of physicochemical and spectrometric analysis as quercetin (1), 3,5,7,8,4'-pentahydroxy-3'-methoxy flavone (2), 3-O-methylquercetin (3), 3,3'-di-O-methylquercetin (4), 3,3'-di-O-methylquercetin-7-O-β-d-glucopyranoside (5), isorhamentin-3-O-β-d-rutinoside (6), 8-O-methylretusin (7), 8-O-methylretusin-7-O-β-d-glucopyranoside (8), salicylic acid (9), p-hydroxybenzoic acid (ferulic acid) (10), and 4-hydroxy-3-methoxy cinnamic acid (11). They were sorted as flavonols (1-6), soflavones (7 and 8), and phenolic acids (9-11). Among the compounds, flanools 1-4 revealed a strong antibacterial activity with minimum inhibitory concentration (MIC) values of 50-150 μg/mL, and median inhibitory concentration (IC(50)) values of 26.8-125.1 μg/mL. The two isoflavones (7 and 8) showed moderate inhibitory activity on the test bacteria. Three phenolic acids (9, 10 and 11) showed strong antibacterial activity with IC(50) values of 28.1-149.7 μg/mL. Antifungal activities of the compounds were similar to their antibacterial activities. All these phenolic compounds showed significant antimicrobial activity with a broad spectrum as well as antioxidant activity based on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and β-carotene-linoleic acid bleaching assays. In general, the flavonol aglycones with relatively low polarity exhibited stronger activities than the glycosides. The results suggest the potential of this plant as a source of functional food ingredients and provide support data for its utilization as forage as well.
International Journal of Molecular Sciences 01/2012; 13(9):11349-64. · 2.60 Impact Factor
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ABSTRACT: Ustiloxins are cyclopeptide mycotoxins produced by the pathogenic fungus Villosiclava virens of rice false smut. Ustiloxins A and B as two main mycotoxins were determined conveniently by LC-ESI-MS in the water extract from rice false smut balls which were mostly composed of the chlamydospores and mycelia of the pathogen. Both ustiloxins A and B in the water extract were also quantitatively analyzed by HPLC. This is the first report on the determination and analysis of ustiloxins A and B simultaneously by LC-ESI-MS and HPLC in false smut balls of rice.
International Journal of Molecular Sciences 01/2012; 13(9):11275-87. · 2.60 Impact Factor
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ABSTRACT: A series of novel 5-(4-hydroxybenzyl)-2-thioxoimidazolidin-4-one esters were synthesized under mild conditions by the reaction of 5-(4-hydroxybenzyl)-2-thioxoimidazolidin-4-one and carboxylic acids with DCC and DMAP as the promoters. Their structures were confirmed by ¹H-NMR, IR, ESI-MS and elemental analysis. The preliminary bioassy results indicated that some of compounds exhibit good herbicidal activity against Zea mays, Triticum aestivum and Arabidopsis thaliana. The further greenhouse test showed that compounds 6-16 and 6-28 have 60%, 50% and 50% efficacy against Stellaria media, Echinochloa crus-galli and Setaria viridis at 1,000 g/ha, respectively.
Molecules 01/2011; 16(4):2833-45. · 2.39 Impact Factor
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ABSTRACT: A bioassay-guided fractionation of the ethyl acetate extract from the twigs of the hybrid poplar 'Neva', Populus nigra L. × Populus deltoides Marsh, led to the isolation of three flavonoids, which were identified by means of spectrometric and physicochemical analysis as 5-hydroxy-7-methoxy-flavone (1), 5,7-dihydoxy-flavone (2) and 5,7-dihydroxy-flavonol (3). These compounds were further screened for their antimicrobial activity against plant pathogens, including three bacteria (Pseudomonas lachrymans, Ralstonia solanacearum and Xanthomonas vesicatoria) and one fungus (Magnaporthe oryzae). Compounds 2 and 3 showed significant antibacterial activity, with minimum inhibitory concentrations (MICs) ranging from 15 to 25 µg mL(-1), and median inhibitory concentrations (IC(50) values) from 4 to 18 µg mL(-1). The results obtained provide promising baseline information for the potential use of the extract and flavonoids from this plant as antimicrobial agents to help control plant diseases.
Natural product research 01/2011; 26(4):307-13. · 1.01 Impact Factor
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ABSTRACT: A new C₉ monoterpenoid acid (litseacubebic acid, 1) and a known monoterpene lactone (6R)-3,7-dimethyl-7-hydroxy-2-octen-6-olide (2), along with three known compounds--vanillic acid (3), trans-3,4,5-trimethoxylcinnamyl alcohol (4), and oxonantenine (5)--were isolated with bioassay-guided purification from the fruit extract of Litsea cubeba collected in Tibet. The structure of 1 was elucidated by MS, ¹H-NMR, ¹³C-NMR, COSY, HSQC, HMBC, NOE spectral data as 2,6-dimethyl-6-hydroxy-2E,4E-hepta-2,4-diene acid. Additionally 33 compounds were identified from the essential oil of L. cubeba. The preliminary bioassay results showed that 1 and 2 have good fungicidal activities against Sclerotinia sclerotiorum, Thanatephorus cucumeris, Pseudocer-cospora musae and Colletotrichum gloeosporioides at the concentration of 588 and 272 μM, and the essential oil has good fungicidal activities against T. cucumeris and S. sclerotiorum, with IC₅₀ values of 115.58 and 151.25 μg/mL, repectively.
Molecules 01/2010; 15(10):7075-82. · 2.39 Impact Factor
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ABSTRACT: Using methanesulfonic acid as a catalyst, a series of cyclododeceno[b]indene derivatives were synthesized by the cyclization of alpha-benzylcyclododecanones, which were prepared by the reactions of cyclododecanones with a variety of substituted benzyl chlorides or bromides using NaH as a base. Their structures were confirmed by mp, IR spectra, 1H-NMR, 13C-NMR, MS, and x-ray diffraction. The preferred conformations were analyzed by crystal structure, 1H-NMR and quantum chemistry calculations, and compared with the x-ray diffraction structure of 2,3,5,6-bis(ortho-1,10-decylidene)dihydropyrazine. The results showed that the cyclododecene moiety adopted a preferred [1ene2333] conformation, and the substituted groups at aromatic ring had no significant influence on the conformation.
Molecules 01/2010; 15(2):699-708. · 2.39 Impact Factor
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ABSTRACT: Three steroids and one nordammarane triterpenoid were isolated for the first time from the endophytic fungus Pichia guilliermondii Ppf9 derived from the medicinal plant Paris polyphylla var. yunnanensis. By means of physicochemical and spectrometric analysis, they were identified as ergosta-5,7,22-trienol (1), 5α,8α-epidioxyergosta-6,22-dien-3β-ol (2), ergosta-7,22-dien-3β,5α,6β-triol (3), and helvolic acid (4). Both micro-dilution-colorimetric and spore germination assays were employed to evaluate their antimicrobial activity. Among them, helvolic acid (4) exhibited the strongest antibacterial activity against all test bacteria, with MIC values ranging from 1.56 µg/mL to 50 µg/mL, and IC(50) values from 0.98 µg/mL to 33.19 µg/mL. It also showed strong inhibitory activity on the spore germination of Magnaporthe oryzae with an IC(50) value of 7.20 µg/mL. Among the three steroids, 5α,8α-epidioxyergosta-6,22-dien-3β-ol (2) exhibited relatively strong antimicrobial activity. The results suggest that the endophytic fungus Pichia guillermondii Ppf9 could be a candidate for producing helvolic acid, and the metabolites from this fungus could be potentially developed as antimicrobial agents in the future.
Molecules 01/2010; 15(11):7961-70. · 2.39 Impact Factor
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ABSTRACT: Seven flavonoids have been isolated from the aerial parts of Halostachys caspica C. A. Mey. (Chenopodiaceae) for the first time. By means of physicochemical and spectrometric analysis, they were identified as luteolin (1), chrysin (2), chrysin 7-O-β-D-glucopyranoside (3), quercetin (4), quercetin 3-O-β-D-glucopyranoside (5), isorhamentin-3-O-β-D-glucopyranoside (6), and isorhamentin-3-O-β-D-rutinoside (7). All flavonoids were evaluated to show a broad antimicrobial spectrum of activity on microorganisms including seven bacterial and one fungal species as well as pronounced antioxidant activity. Among them, the aglycones with relatively low polarity had stronger bioactivity than their glycosides. The results suggested that the isolated flavonoids could be used for future development of antimicrobial and antioxidant agents, and also provided additional data for supporting the use of H. caspica as forage.
Molecules 01/2010; 15(11):7933-45. · 2.39 Impact Factor
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ABSTRACT: Two sterols and one fatty acid were obtained by bioassay-guided fractionation from the light petroleum extract of the fungus Fusarium sp. Ppf4 isolated from the rhizomes of Paris polyphylla var. yunnanensis Hand.-Mazz., a medicinal species distributed in the southwest of China. The compounds were elucidated as 5alpha, 8alpha-epidioxyergosta-6, 22-dien-3beta-ol (1), ergosta-8(9), 22-dien-3beta, 5alpha, 6beta, 7alpha-tetraol (2), and butanedioic acid (3), respectively, by means of physical and spectrometric analysis. Both fungal spore germination and micro-dilution-MTT assays were employed to evaluate their antimicrobial activity. Compound 1 was found to be the most bioactive, and compound 3 less active against the test pathogens. This is the first report of the antimicrobial activity of the compounds isolated from the endophytic Fusarium sp. Ppf4 associated with P. polyphylla var. yunnanensis. The results provide promising baseline information for the potential use of the compounds of this endophytic fungus as an antimicrobial agent to control plant and animal diseases.
Natural product communications 11/2009; 4(11):1455-8. · 1.24 Impact Factor
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ABSTRACT: Five spirobisnaphthalenes, namely palmarumycin CP17 (1), diepoxin kappa (2), diepoxin eta (3), diepoxin xi (4), and diepoxin gamma (5), were isolated from the endophytic fungus Dzf12 associated with the medicinal plant Dioscorea zingiberensis C. H. Wright. Their structures were identified by physicochemical and spectrometric analysis. Among these spirobisnaphthalenes, 2 was found to have antibacterial activity, and the mixture of 3 and 4 was detected to have both antibacterial and antifungal activities.
Natural product communications 11/2009; 4(11):1469-72. · 1.24 Impact Factor
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ABSTRACT: Volatile oils were obtained by hydro-distillation from Gliomastix murorum and Pichia guilliermondii, two endophytic fungi isolated from the traditional Chinese medicinal herb Paris polyphylla var. yunnanensis. The oils were analyzed for their chemical composition by gas chromatography-mass spectrometry (GC-MS). Palmitic acid (15.5%), (E)-9-octadecenoic acid (11.6%), 6-pentyl-5,6-dihydropyran-2-one (9.7%), and (7Z,10Z)-7,10- hexadecadienoic acid (8.3%) were the major compounds of the 40 identified components in G. murorum volatile oil. 1,1,3a,7-Tetramethyl-1a,2,3,3a,4,5,6,7b-octahydro-1H-cyclopropa[a]- naphthalene (25.9%), palmitic acid (15.5%), 1-methyl-2,4-di- (prop-1-en-2-yl)-1- vinylcyclohexane (7.9%), (E)-9-octadecenoic acid (7.3%), and (9E,12E)-ethyl-9,12-octadecadienoate (5.2%) were the major compounds of the 27 identified components in P. guilliermondii volatile oil. The in vitro antimicrobial activity of the volatile oils was also investigated to evaluate their efficacy against six bacteria and one phytopathogenic fungus. The minimum inhibitory concentration (MIC) values of the volatile oils against the test bacteria ranged from 0.20 mg/mL to 1.50 mg/mL. One of the most sensitive bacteria was Xanthomonas vesicatoria with an MIC of 0.20 mg/mL and 0.40 mg/mL for G. murorum and P. guilliermondii, respectively. The mean inhibitory concentration (IC50) of the volatile oils against spore germination of Magnaporthe oryzae was 0.84 mg/mL for G. murorum and 1.56 mg/mL for P. guilliermondii. These results indicated that the volatile oils from the endophytic fungi have strong antimicrobial activity and could be a potential source of antimicrobial ingredients.
Natural product communications 11/2009; 4(11):1491-6. · 1.24 Impact Factor
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ABSTRACT: Three new sesquiterpene polyol esters with a beta-dihydroagarofuran skeleton, NW12 (1), NW27 (2), and NW31 (4), together with a known compound, NW30 (3), were isolated from the root bark of Celastrus angulatus. Their chemical structures were elucidated by analyses of MS and NMR spectral data. Preliminary insecticidal and antitumor activities of these compounds were evaluated. Compounds 1-4 showed moderate stomach toxicity against Mythimna separata, and their KD50 values were 673.6, 1121.3, 1720.0 and 548.6 microg/g, respectively. Only 1 and 3 exhibited slight antitumor activity against human breast cancer cell line (Bcap-37), and their IC50 values were all above 50 microM.
Natural product communications 05/2009; 4(4):461-6. · 1.24 Impact Factor
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ABSTRACT: Five streptothricin acids (compounds 1-5) were isolated by ion-exchange resin chromatography and preparative RP-HPLC from the fermentation broth of Streptomyces qinlingensis. Their structures were elucidated mainly by analyses of the IR, HR-EIS-MS and NMR spectral data. They were deduced as two known compounds, streptothricin F acid (1) and streptothricin D acid (2), and three new compounds, 12-carbamoylstreptothricin E acid (3), 12-carbamoylstreptothricin D acid (4) and N-acetyl-streptothricin D acid (5), respectively. The antibacterial activities of 1-5 against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Bacillus cereus and Pseudomonas aeruginosa were assayed by micro-broth dilution. Comparison of the MICs with streptothricin F and D showed that the antimicrobial activities of 1-5 were decreased significantly but varied with the structures.
The Journal of Antibiotics 04/2009; 62(5):233-7. · 1.65 Impact Factor
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ABSTRACT: A new aromatic triterpene was isolated from the root bark EtOAc extract of Euonymus japonicus Thunb, and its chemical structure was elucidated mainly by analysis of MS and NMR spectra.
Natural product research 02/2009; 23(7):617-21. · 1.01 Impact Factor
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ABSTRACT: A new lactone was isolated from the leaves of Xylocarpus granatum, along with three known compounds: triacontanol, beta-sitosterol and kaempferol-3-O-beta-D-glucoside. Its structure was elucidated as 3-(1-hydroxyethyl)-4,4-dimethyl-4-butyrolactone (1) by infrared, (1)H and (13)C NMR and ESI-MS data. At a concentration of 20 microg mL(-1), the new lactone gave a 67.4% inhibition rate against wheat powdery mildew.
Natural product research 02/2009; 23(14):1316-21. · 1.01 Impact Factor
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ABSTRACT: Two new insecticidal sesquiterpene esters with a beta-dihydroagarofuran sesquiterpene skeleton, ejaponine A (1) and ejaponine B (2), and two known compounds, 3 and 4, were isolated from the EtOAc extract of the root bark of Euonymus japonicus Thunb. by bioassay-guided fractionation. Their chemical structures were elucidated mainly by analysis of MS and NMR spectral data. The LD50 values of ejaponine A (1), ejaponine B (2), 3 and 4 showed against Mythimna separata were 89.2, 98.6, 181.4 and 109.2 microg g(-1), respectively.
Natural product research 01/2009; 23(15):1402-7. · 1.01 Impact Factor
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Journal of Essential Oil Research 01/2009; 21(2):174-178. · 0.41 Impact Factor
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ABSTRACT: Several streptothricin antibiotics have been studied by tandem mass spectrometry. The dominant product ions were derived from the C7-N bond cleavage which lead to lose streptolidine from the [M+H]+. The fragmentation pathways of key ions were described and certained by parent scan. According to the generalized principles, streptothricin isomers could be distinguished easily by the difference of CID spectra. A facile method based on ion-pair RP-HPLC coupled with electrospray ionization tandem mass spectrometry has been established for the analysis of streptothricins in the fermentation broth of Streptomyces qinlingensis. A total of 19 streptothricinlike compounds were identified or tentatively characterized based on their mass spectral data, and in which 11 were the first reported compounds. This could be used as an important de-replication method in the programs of screening novel antibiotics.Keywords: streptothricins, electrospray ionization, tandem mass spectometry, structural characterization
The Journal of Antibiotics 10/2008; 61(11):660-667. · 1.65 Impact Factor
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ABSTRACT: Four streptothricin-group antibiotics (1~4) were isolated from the fermentation broth of Streptomyces qinlingensis sp. nov. Along with the known antibiotics streptothricins F (1) and D (3), two new members of this class (2, 4) were identified as 12-carbamoyl derivatives of 1 and 3, respectively, mainly by analysis of the IR, HR-MS and NMR spectral data. The antibacterial activities of 1~4 against Escherichia coli (MICs 3.1, 25.0, 3.1 and 12.5 microg/ml), Bacillus subtilis (MICs 6.3, 25.0, 3.1 and 50 microg/ml), Staphylococcus aureus (MICs 12.5, >100.0, 6.3, >100.0 microg/ml), Bacillus cereus (MICs 25.0, 50.0, 25.0 and 50.0 microg/ml) and Pseudomonas aeruginosa (MICs 50.0, >100.0, 50.0, >100.0 microg/ml) were assayed by micro-broth dilution. The results based on MIC data indicated that 2 and 4 exhibited significantly less potent antibacterial activities when compared to that of 1 and 3.
The Journal of Antibiotics 12/2007; 60(12):739-44. · 1.65 Impact Factor
