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Biomedical subjects

M Wurst

Publications and source records attributed to M Wurst.

18 recordsLinked to original sources
PubMed2002

Psychoactive tryptamines from basidiomycetes.

The review lists natural sources, i.e. strains and species of fungi producing predominantly psychoactive tryptamines (indolealkylamines), their chemical structure and properties, toxic effects on the man and psychic symptoms of intoxication. It describes the biosynthesis and production of some tryptamines by the mycelial culture of Psilocybe bohemica Sebek, a survey of methods for their analysis and isolation. It evaluates the worldwide use and abuse of psychoactive fungi as sources of drugs in general and in the Czechia in particular during the last two and a half decades.

Basidiomycota↗
PubMed1997

Ergot alkaloids--sources, structures and analytical methods.

Natural sources, i.e. fungal strains and species producing ergot alkaloids (EA), are surveyed together with the chemical structures of EA and a list of new natural EA discovered in the last three decades. Other topics include new efficient chromatographic methods (HPLC) for the separation and isolation of new natural EA and also immunological methods of EA detection.

Chromatography, High Pressure Liquid↗
PubMed1990

Production and characteristics of the exocellular polysaccharide of a mutant Mycobacterium strain.

Mutant strains of Mycobacterium sp. V-649 producing highly mucous colonies on a solid cultivation medium were prepared after treatment with N-methyl-N'-nitro-N-nitrosoguanidine and production of the exocellular polysaccharide was tested. The strains were cultivated in media with suitable sugar sources under submerged conditions. It was found that Mycobacterium sp. V-649/15 produces a maximum of 15-19% polymer after a 5-6-d cultivation. Gas chromatography indicated that the exocellular polysaccharide produced by this strain is of glucan type.

Chromatography, Gas↗
PubMed1989

Quantitative analysis of fatty acid methyl esters by capillary gas chromatography with flame-ionization detection: quadrupole and sector mass spectrometer.

The response of a flame-ionization detector and of two mass detectors, viz. a quadrupole mass spectrometer and a sector mass spectrometer, is described. A relationship between the amount of a fatty acid methyl ester and the relative response in the three detectors was found. The detectors were compared and their possible use for biological samples was discussed.

Carboxylic Acids↗
PubMed1988

Chromatography of microbial metabolites of aromatic amino acids.

A mixture of hydroxy-, methoxy- and aminobenzenecarboxylic acids (aromatic acids) was studied by gas (GC) and liquid (LC) chromatography. The gas and high-performance liquid chromatographs were attached to a computer. The GC method yielded elution data for trimethylsilyl derivatives of a large number of aromatic acids on four stationary silicone phases, OV-1, SE-52, OV-17 and 1,5-bis(m-phenoxyphenyl)-1,1,3,3,5,5-hexaphenyltrisiloxane. HPLC measurements afforded capacity factors, k, for these aromatic acids on a reversed stationary phase as a function of the mobile phase composition, which consisted of methanol (or ethanol), water and acetic acid. The GC and LC separation systems were described by an empirical function, embodying parameters such as the resolution, R, standard deviation, s, analysis time, t, and time for preparative work, tp. Evaluation of the optimization function enabled assessment of the applicability of the chromatographic methods to the analysis and isolation of natural metabolites of aromatic amino acids from microbial material.

Agaricales↗
PubMed1984

Extracellular metabolism of sucrose in a submerged culture of Claviceps purpurea: formation of monosaccharides and clavine alkaloids.

Transformation of extracellular sucrose during cultivation of Claviceps purpurea led to the formation of mono- and oligosaccharides. Maltose was a suitable substrate for submerged fermentation of alkaloids. Fermentation in a medium with maltose was characterized by an insignificant formation of glucans, intensive sporulation, suspension growth of mycelium, and a higher formation of elymoclavine. Glucose alone yielded low levels of total alkaloids and high glucan formation; on the other hand, glucose promoted the formation of elymoclavine.

Claviceps↗
PubMed1983

Discriminative stimulus properties of a small dose of cocaine.

This study characterized the interoceptive discriminative stimulus (IDS) produced by a small dose of cocaine. Rats were trained to use a dose of cocaine of 1.25 mg/kg vs saline as the basis for choosing one of two levers for food reinforcement on a fixed ratio 10 schedule. The discrimination was acquired over approx. 60 training sessions. d-Amphetamine generalized to cocaine with approximately equal potency (ED50's for cocaine and d-amphetamine were 0.07 and 0.06 mg/kg, respectively); 20 mg/kg cocaine and 10 mg/kg methylphenidate also generalized to the cocaine lever. Pentylenetetrazol, 20 mg/kg, did not generalize to the cocaine lever, and diazepam, 10 mg/kg, did not block the 1.25 mg/kg cocaine discrimination. These data indicate that when a small dose of cocaine is used as the basis of discrimination training, the discriminative stimulus that it produces is qualitatively and quantitatively similar to that produced by small doses of amphetamine, is still discriminated with a large dose of cocaine, and is dissimilar to the discriminative stimulus produced by pentylenetetrazol.

Animals↗
PubMed1982

Metabolism of aromatic acids in the antibiotic-producing basidiomycete Oudemansiella mucida.

Aromatic acids were determined in the mycelium and fermentation medium of Oudemansiella mucida. Coumaric acids (both m- and p-), p-hydroxybenzoic acid (salicylic acid) and benzoic acid were found to predominate in the mycelium. Phenylacetic acid represents the main component in the medium. Phenylalanine ammonia-lyase catalyzing conversion of phenylalanine to cinnamic acid which is further metabolized to benzoic acid was detected in the mycelium. The results are discussed with respect to the synthesis of the antibiotic mucidin.

Alkenes↗
PubMed1980

Gas chromatographic determination of extracellular metabolites produced by baker's yeast during glucose-induced acidification.

Gas chromatographic separation of metabolites extruded during the medium acidification by resting baker's yeast supplied with glucose is described. Silylation with bis(trimethylsilyl)trifluoroacetamide and trimethylchlorosilane and a direct chromatography on Chromosorb G-AW-DMCS with 2.5% SE-52 (lactic, pyruvic, succinic, glyceric, fumaric, malic), polyols (glycerol, arabinitol) and sugars (glucose). The yeast was found to extrude glycerol, lactic, malic, and succinic acid.

Chromatography, Gas↗
PubMed1980

Extrusion of metabolites from baker's yeast during glucose-induced acidification.

Extrusion of metabolites (glycerol, lactic, malic, and succinic acid) during the medium acidification caused by resting baker's yeast supplied with 200 mM glucose was studied under aerobic and anaerobic conditions and in the absence and presence of 14 mM KCl. The maximum levels of glycerol and of the sum of acids (about 13 and 8 mM, respectively) were attained anaerobically; aerobiosis reduced the levels by 40-50% and the presence of K+ ions by another 10-20%. The time courses of glucose consumption and medium acidification were similar aerobically and anaerobically. The glucose consumption curves exhibited a short plateau about 2 min after glucose addition, caused probably by a rapid osmotic equilibration of glucose across the cell mambrane. Metabolite extrusion indicates that at high glucose concentrations the alcohol dehydrogenase reaction is supplemented by other reactions aiding in the maintenance of a balanced NAD+/NADH ratio in the cells.

Anaerobiosis↗
PubMed1979

Effect of bacterial polysaccharides on the growth of Gaeumannomyces graminis var. tritici and wheat roots.

Agrobacterium sp. and related species which in the soil and in the rhizosphere of wheat accompany the fungus Gaemannomyces graminis var. tritici and cause take-all of the wheat roots produced polysaccharides in pure cultures (glucans, mannoglucans and galactomannoglucans). These polysaccharides were utilized better by the mycelium of G. graminis than glucose and polysaccharides of plant origin that occurred on the surface of wheat roots (the so-called mucigel). At lower concentrations these bacterial polysaccharides stimulated growth of wheat roots, higher concentrations (more than 0.1%) were inhibitory. Bacteria inoculated on the surface of wheat first inhibited and then stimulated the development of the plants and their growth. Changes in the growth rate of wheat, the rhizosphere of which was colonized by bacteria simultaneously with the fungus G. graminis and also some changes in the course of the disease of wheat roots caused by the fungus can be explained by the inhibitory or stimulatory effect of polysaccharides of accompanying bacteria.

Ascomycota↗
PubMed1978

Fatty acids in green algae cultivated on a pilot-plant scale.

Fatty acids from Chlorella vulgaris, Scenedesmus obliquus var. acutus and from a mixed culture of the two strains, Melnik, were converted to methyl esters, separated by gas chromatography, and identified by means of standards. The spectrum of fatty acids included both saturated and unsaturated acids (with odd and even numbers of carbon atoms) from C12 to C22. Fatty acids C16:0, C18:0 and C20:3 were the major components in all cultures. Pure strains differed from the mixed culture in the production of C18:1, C12:0 and C19:2 acids; the first of these was present in higher amounts in pure cultures only, the latter two being found in the mixed culture. The level of lipids was lower as compared to the literature data and their extractability was affected by the manner of preparation of algae and extraction conditions.

Chlorella↗
PubMed1978

Soluble sugars in the mycelium of the basidiomycete Oudemansiella mucida.

Quantitative gas chromatography was used to determine soluble neutral sugars in an extract of the fungus Oudemansiella mucida grown on a synthetic glucose medium. Apart from the usual fungal sugar components, viz. trehalose, D-glucose, D-mannitol, D-arabinitol, glycerol and inositol, the 6-day-old mycelium contained D-arabino-2-hexosulose (D-glucosone). In the period of maximum growth, this aldoketose was the predominant monosaccharide (3.4% mycelial dry weight).

Basidiomycota↗
PubMed1977

Production and characteristics of the exocellular polysaccharide in mutant strains of Xanthomonas fuscans.

Production of the exocellular polysaccharide of the phytopathogenic bacterium Xanthomonas fuscans was investigated with respect to its possible use in utilization of industrial wastes containing lactose. Six stable lac+ mutants were obtained after the treatment with N-methyl-N-nitroso-N'-nitroguanidine. The mutants were compared with the parent strain. Morphological and cultivation characteristics, as well as production of the exocellular polysaccharide were compared. The production was found to be maximal during the stationary phase of growth in strains cultivated under submerged conditions. Gas chromatography revealed that the polysaccharide of the parent strain is formed by alpha- and beta-D-glucose and alpha- and beta-D-mannose with a small amount of D-ribose and 6-deoxy-L-mannose. Composition of the polysaccharides produced by the mutant strains (lac+) does not qualitatively differ from that of the parent strain. However, they were found to contain a higher quantity of D-mannose, which is favourable for their industrial utilization.

Galactose↗
PubMed1976

Content of fatty acids of Chlorella kessleri in a deep tank fermentation.

Chlorella kessleri cultivated in a deep tank contained 4.8% of non-polar lipid; 51% of this fraction represents saturated fatty acids, 7% unsaturated fatty acids. Our investigation of the fatty acids profile demonstrated even- and odd-numbered saturated and unsaturated fatty acids ranging from C12 to C20. Unlike in other Chlorella species, stearic acid was the dominant fatty acid found. Also shown was an elevated C16:0 fatty acid content and a reduced level of unsaturated fatty acids.

Chlorella↗