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H Anke

Publications and source records attributed to H Anke.

At least 37 records · Page 2Linked to original sources
PubMed1995

Structure-activity relationships for unsaturated dialdehydes. 10. The generation of bioactive products by autoxidation of isovelleral and merulidial.

The autoxidation of the two mutagenic and antimicrobial sesquiterpenes merulidial (1a) and isovelleral (5) generates a number of bioactive products that are suggested to be partly responsible for the mutagenic and antimicrobial activities of the two compounds. The biological activities of the autoxidation products are, as far as has been possible to assay, of the same order as the parent compounds, and it is shown that they are formed in normal bioassay media. Merulidial (1a) is especially interesting, as its rate of autoxidation is considerably higher compared with non-mutagenic derivatives of 1a. In addition, natural isovelleral [(+/-)-5] was found to be twice as mutagenic as synthetic isovelleral [(+/-)-5], indicating that (-)-isovelleral is only weakly active or inactive, and supporting the suggestion that the interaction of isovelleral (5) and its derivatives with DNA depends on the absolute stereochemistry of the unsaturated dialdehyde moiety.

Aldehydes↗
PubMed1995

Metabolites with nematicidal and antimicrobial activities from the ascomycete Lachnum papyraceum (Karst.) Karst. V. Production, isolation and biological activities of bromine-containing mycorrhizin and lachnumon derivatives and four additional new bioactive metabolites.

Eight novel bioactive metabolites were isolated from submerged cultures of the ascomycete Lachnum papyraceum (Karst.) Karst, when CaBr2 was added to the cultures after the onset of secondary metabolism. Four of these metabolites (16 to 19) are bromo analogues of mycorrhizin A and lachnumon, while (l'Z)-dechloromycorrhizin A (12) and the papyracons A (13), B (14), and C (15) are non-halogenated compounds structurally related to the mycorrhizins. All compounds exhibited antimicrobial, cytotoxic, nematicidal and phytotoxic activities. The brominated mycorrhizins and lachnumons were found to be slightly less active than the chlorine-containing compounds. All mycorrhizin derivatives were mutagenic in the Ames test, suggesting DNA-alkylating properties.

Animals↗
PubMed1995

New metabolites with nematicidal and antimicrobial activities from the ascomycete Lachnum papyraceum (Karst.) Karst. VI. Structure determination of non-halogenated metabolites structurally related to mycorrhizin A.

The structure determination of four new biologically active non-halogenated metabolites isolated from submerged cultures of the ascomycete Lachnum papyraceum is described. The compounds are structurally related to the antibiotic mycorrhizin A: (l'Z)-Dechloromycorrhizin A (12), a stereoisomer of dechloromycorrhizin A (5) previously isolated from the same fungus, as well as papyracon A (13), papyracon B (14) and papyracon C (15) containing an exocyclic double bond. The amounts of the latter three increased significantly when CaBr2 was added to the culture medium. The structures were determined by spectroscopic methods.

Anti-Bacterial Agents↗
PubMed1995

New metabolites with nematicidal and antimicrobial activities from the ascomycete Lachnum papyraceum (Karst.) Karst. VII. Structure determination of brominated lachnumon and mycorrhizin A derivatives.

The structure determination of lachnumon B1 (16) and lachnumon B2 (17), brominated derivatives of lachnumon (1), as well as mycorrhizin B1 (18) and mycorrhizin B2 (19), brominated derivatives of mycorrhizin A (3), is described. The compounds, which exhibit similar antimicrobial and nematicidal activity as their chlorinated analogues, were isolated from extracts of cultures of the ascomycete Lachnum papyraceum to which CaBr2 had been added. The structures were elucidated by spectroscopic methods.

Anti-Bacterial Agents↗
PubMed1995

Metabolites with nematicidal and antimicrobial activities from the ascomycete Lachnum papyraceum (Karst.) Karst. III. Production of novel isocoumarin derivatives, isolation, and biological activities.

During investigations on the influence of CaBr2 on the secondary metabolism of Lachnum papyraceum, the production of mycorrhizins and lachnumon type antibiotics was strongly inhibited in bromide-containing culture media. Instead, six isocoumarin derivatives, 6-hydroymellein (6), 4-chloro-6-hydroxymellein (7), 4-bromo-6-hydroxymellein (9), 6-methoxymellein (10). 4-chloro-6-methoxymellein (11), and 4-chloro-6,7-dihydroxymellein (12) were isolated. Compounds 7, 9, 11, and 12 have never been isolated from natural sources. 6-Hydroxymellein has been isolated previously from many sources including Gilmaniella humicola and proposed to be a precursor of mycorrhizin A (see reference 6). In comparison to the mycorrhizins, the isocoumarin derivatives exhibited only weak antimicrobial, cytotoxic, phytotoxic, and nematicidal activities.

Animals↗
PubMed1995

New metabolites with nematicidal and antimicrobial activities from the ascomycete Lachnum papyraceum (Karst.) Karst. IV. Structural elucidation of novel isocoumarin derivatives.

The structures of four new biologically active halogenated dihydroiso coumarins isolated from submerged cultures of the ascomycete Lachnum papyraceum have been elucidated by spectroscopic methods. The compounds are structurally related to lachnumon and mycorrhizin A, which are also produced by the fungus.

Anti-Infective Agents↗
PubMed1995

Darlucins A and B, new isocyanide antibiotics from Sphaerellopsis filum (Darluca filum).

Two new xanthocillin type antibiotics, darlucin A (1) and B (2), were isolated from fermentations of Sphaerellopsis filum (Darluca filum). Their structures were established by spectroscopic methods. The darlucins are the first known compounds with a 1,2-diisocyanoalkene moiety. Both compounds exhibited antibacterial, antifungal and weak cytotoxic activities.

Animals↗
PubMed1994

Metabolism of the polycyclic aromatic hydrocarbon pyrene by Aspergillus niger SK 9317.

The metabolism of pyrene, a polycyclic aromatic hydrocarbon consisting of four rings, by Aspergillus niger SK 9317 was investigated. The metabolites formed were isolated and identified as 1-hydroxypyrene, 1,6- and 1,8-pyrenequinone, 1,6- and 1,8-dihydroxypyrene, 1-pyrenyl sulphate and 1-hydroxy-8-pyrenyl sulphate. This is the first report of 1-hydroxy-8-pyrenyl as a metabolite in the microbial metabolism of pyrene. The results suggest that A. niger metabolizes pyrene by cytochrome P-450 monooxygenase enzyme systems.

Aspergillus niger↗
PubMed1994

Novel bioactive diterpenoids from Aframomum aulacocarpos.

Three new labdane diterpenes, 12 alpha,17-epoxy-3 beta-hydroxy-8(9),13- labdadien-16,15-olide (aulacocarpinolide) [1], methyl 8 beta,17:14 zeta,15-diepoxy-3 beta-hydroxy- 12E-labden-16-oate (aulacocarpin A) [2], and methyl 8 beta,17:14 zeta,15-diepoxy-3 beta,6 beta- dihydroxy-12E-labden-16-oate (aulacocarpin B) [3] have been isolated from the Cameroonian spice, Aframomum aulacocarpos, and their structures elucidated using spectroscopic techniques. The known bioactive diterpene dialdehyde, 8 beta,17-epoxy-12E-labdene-15,16-dial (aframodial) [4] was also isolated. Compounds 1-3 showed weak antimicrobial and cytotoxic activities.

Africa↗
PubMed1994

Fatty acids and other compounds with nematicidal activity from cultures of Basidiomycetes.

In a screening for nematicidal activities in cultures of Basidiomycetes, cultures of Pleurotus pulmonarius and Hericium coralloides exhibited toxic effects towards the saprophytic nematode Caenorhabditis elegans. Subsequently S-coriolic acid (1), linoleic acid (2), p-anisaldehyde (3), p-anisyl alcohol (4), 1-(4-methoxyphenyl)-1,2-propanediol (5), and 2-hydroxy-(4'-methoxy)-propiophenone (6) were isolated from submerged cultures of P. pulmonarius. All compounds showed nematicidal activities towards C. elegans. The most active compounds were 1 and 2 with LD50 values between 5 and 10 ppm. Compounds 1, 4, and 5 have not been previously isolated from higher fungi, 6 is a new natural product. From cultures of H. coralloides, which exhibited both repellant and nematicidal effects, a nematicidal fatty acid mixture was obtained, containing linoleic acid, oleic acid, and palmitic acid as its main components.

Animals↗
PubMed1994

Nematicidal activities of two phytoalexins from Taverniera abyssinica.

The traditional analgesic and antipyretic Ethiopian drug "Dingetegna" is made of dried root material of Taverniera abyssinica A. Rich (Leguminosae). In a screening for nematicidal natural products, "Dingetegna" extracts showed strong nematicidal activities towards C. elegans. In the following, medicarpin and 4-hydroxymedicarpin were isolated as nematicidal constituents from the extracts. In a microwell plate assay for nematicidal activity, both compounds exhibited an LD50 of 25 micrograms/ml towards C. elegans. Beside these nematicidal effects, weak cytotoxic and antimicrobial activities were observed. In addition, both compounds inhibited oxygen consumption of axenically grown C. elegans, L 1210 cells, and filamentous fungi. Respiration in sensitive bacteria was not affected. In L 1210 cells, the incorporation of precursors into macromolecules was affected in the presence of glucose, indicating that inhibition of respiration is not the only target site of the compounds.

Animals↗
PubMed1994

Metabolism of Pyrene by the Basidiomycete Crinipellis stipitaria and Identification of Pyrenequinones and Their Hydroxylated Precursors in Strain JK375.

The metabolism of pyrene, a polycyclic aromatic hydrocarbon, by submerged cultures of the basidiomycete Crinipellis stipitaria was studied. After incubation for 68 h at 25 degrees C in a 20-liter fermentor with complex medium and 20 mg of pyrene per liter, five metabolites were detected. The compounds were isolated by preparative high-performance liquid chromatography on RP18 and DIOL gels. By UV, infrared, and H nuclear magnetic resonance spectroscopy and mass spectrometry, 1-hydroxypyrene, 1,6-dihydroxypyrene, 1,8-dihydroxypyrene, 1,6-pyrenequinone, and 1,8-pyrenequinone were identified. 1,6- and 1,8-dihydroxypyrene were obtained from fungal cultures for the first time. The formation of these metabolites was confirmed by investigations with [4,5,9,10-C]pyrene.

Journal Article↗
PubMed1994

Pyrene Metabolism in Crinipellis stipitaria: Identification of trans-4,5-Dihydro-4,5-Dihydroxypyrene and 1-Pyrenylsulfate in Strain JK364.

The isolation and identification of two novel metabolites in the fungal metabolism of pyrene are described. The plant-inhabiting basidiomycete Crinipellis stipitaria JK364 metabolized pyrene, a polycyclic aromatic hydrocarbon containing four rings, when grown in submerged cultures in a medium containing malt extract, glucose, and yeast extract. In experiments with [C] pyrene, after 7 days of incubation 40% of the labeled substrate was converted into organic solvent-extractable metabolites. Metabolites isolated from cultures grown with pyrene were identified as 1-pyrenylsulfate and trans-4,5-dihydro-4,5-dihydroxypyrene. 1-Hydroxypyrene, the precursor of 1-pyrenylsulfate, was also detected. 1-Pyrenylsulfate was isolated from mycelial extracts, whereas trans-4,5-dihydro-4,5-dihydroxypyrene was recovered from the culture filtrate. Identification of the compounds was based on their UV spectra, mass spectra, and nuclear magnetic resonance spectra. This is the first report on the detoxification of a polycyclic aromatic hydrocarbon by a plant-inhabiting basidiomycete. The occurrence of 1-pyrenylsulfate and trans-4,5-dihydro-4,5-dihydroxypyrene among fungal metabolites of pyrene is also new.

Journal Article↗
PubMed1994

New nematicidal and antimicrobial compounds from the basidiomycete Cheimonophyllum candidissimum (Berk & Curt.) sing. I. Producing organism, fermentation, isolation, and biological activities.

Six new bisabolane type sesquiterpenoids, cheimonophyllons A (1), B (2), C (3), D (4), E (5), and cheimonophyllal (6) were isolated from the culture fluid of the basidiomycete, Cheimonophyllum candidissimum. The compounds exhibited nematicidal, weak antifungal and antibacterial as well as cytotoxic activities. The main product, cheimonophyllon A (1) (C15H22O4), was also active in the Ames mutagenicity test.

Animals↗
PubMed1993

Lachnumon and lachnumol a, new metabolites with nematicidal and antimicrobial activities from the ascomycete Lachnum papyraceum (Karst.) Karst. I. Producing organism, fermentation, isolation and biological activities.

Several chlorinated metabolites with nematicidal, antimicrobial, and cytotoxic activities were isolated from submerged cultures of the ascomycete Lachnum papyraceum. Three compounds were identified as (+)-mycorrhizin A (3), (+)-chloromycorrhizin A (4) and (+)-dechloromycorrhizin A (5). The occurrence of 5 as a natural product is new. Two compounds, lachnumon (1) and lachnumol A (2), were found to be new fungal metabolites with cytotoxic, nematicidal and antimicrobial activities.

Animals↗
PubMed1993

Lachnumon and lachnumol a, new metabolites with nematicidal and antimicrobial activities from the ascomycete Lachnum papyraceum (Karst.) Karst. II. Structural elucidation.

The structures of two new biologically active chlorinated metabolites isolated from submerged cultures of the ascomycete Lachnum papyraceum have been elucidated by NMR and mass spectroscopy. The compounds, lachnumon (1) and lachnumol A (2), which structurally are related with mycorrhizin A that also is produced by the fungus, contain an unusual chlorinated epoxide group.

Antifungal Agents↗
PubMed1991

Comparison of the antimicrobial and cytotoxic activities of twenty unsaturated sesquiterpene dialdehydes from plants and mushrooms.

Twenty unsaturated sesquiterpene dialdehydes were tested for antimicrobial, algaecidal, cytotoxic, and mutagenic activity. In addition to the known antifungal activity, polygodial (1) also exhibited antibacterial and cytotoxic activity; epipolygodial (2) was slightly less active. The most active compounds were: isovelleral (7), isoisovelleral (8), velleral (20), and methylmarasmate (6). With the exception of velleral (20), they also exhibited mutagenic activity in the Salmonella/microsome assay. Derivatization to less polar compounds usually increased the antimicrobial and cytotoxic effects and reduced mutagenicity, while the introduction of hydroxyl groups had the reverse effect.

Aldehydes↗