M. Wurst

Auxin formation by rhizosphere bacteria as a factor of root growth

Bacteria of the speciesPseudomonas putida andPseudomonas fluorescens isolated from the rhizosphere of maize and bean plants produce indol-3-ylacetic acid and some other auxins when grown in suspension cultures. IAM and ILA were also found besides IAA and its degradation product IAH by means of HPLC and MS methods. This finding indicates the involvement of two different metabolic pathways in IAA synthesis in bacteria. The amounts found varied between 1.6 and 3.3 μg IAA per ml of media which corresponded to 100–200 μg per gram of bacterial dry mass. The effect of IAA production by rhizosphere bacteria on IAA level in the plant is discussed.

Analysis of ergot alkaloids by high-performance liquid chromatography : I. Clavinces and simple derivatives of lysergic acid

Abstract A method of high-performance liquid chromatography has been developed for the separation and quantitative analysis of a mixture of ergot alkaloids on MicroPak NH2 columns using isocratic and gradient elution. The mobile phase is diethyl ether-ethanol. Ultraviolet detection is employed at various wavelengths, and the ergot alkaloids are determined using the method of internal normalization.

Analysis of psychotropic compounds in fungi of the genus psilocybe by reversed-phase high-performance liquid chromatography

Abstract High-performance liquid chromatography (HPLC) was used for the analysis of the minor consistuents psilocybin and psilocin in fungi of the genus Psilocybe. The separation and determination of these compounds was carried out on a stationary phase of LiChrosorb RP-18. The analytical column (A) and semipreparative column (B) were eluted isocratically with water—ethanol—acetic acid (79.2:20:0.8) at flow-rates of 20 ml/h (A) and 180 ml/h (B). The compounds were detected with a UV detector at 267 nm and a fluorometric detector (excitation, 280 nm; emission, 360 nm). The UV detection limit of psilocybin was 20–40 ng (267 nm) and several ng could be detected fluorometrically. The identity of the compounds was verified by HPLC and thin-layer chromatography and by mass spectrometry and UV spectroscopy. The compounds were determined by means of a direct calibration method and by means of the method of internal normalization. The standard deviation of the determination was ±3.4% (relative). The above methods were used to determine these compounds in extracts of fruit bodies of two species of the genus Psilocybe growing at various places in Czechoslovakia, and found to contain 0.25–1.15% of psilocybin and 0.02–0.16% psilocin per dry mass.

Analysis and isolation of indole alkaloids of fungi by high-performance liquid chromatography

Abstract An efficient analytical and isolation method was elaborated for biologically active tryptamines using a computer-aided liquid chromatographic-gas chromatographic system. The separation method includes a new efficient extraction procedure, optimization programmed for high-performance liquid chromatographic separation, identification by diode-array detection and a spectrometric and electrochemical assay. The identification of indole alkaloids was confirmed by thin-layer and gas chromatography and mass spectrometry. The method was used for analysis and isolation of psychotropic substances in extracts from the fruit bodies of hallucinogenic fungi of genera Psilocybe, Inocybe and Amanita and in mycelial extracts from the species Psilocybe bohemica .

High-performance liquid chromatography of plant hormones : II. Determination of plant hormones of the indole type

A high-performance liquid chromatographic (HPLC) method was used to analyze a mixture of plant hormones—intermediates of the naturally occurring phytohormone, indole-3-acetic acid. The determination was performed on an analytical column (A, 250 × 2 mm) preceded by a short (50 × 2 mm) precolumn, and on a semipreparative column (B, 500 × 8 mm). The columns were filled with LiChrosorb RP- 18 and eluted with water-acetic acid-ethanol (79.2:0.8:20) at flow-rates of 40 ml/h (A) and 180 ml/h (B). Detection was done by a UV detector (280 nm) and a fluorometric detector (excitation, 280 nm; emission, 360 nm) connected in series. The detection limit for indole derivatives was 5-20 ng with UV detection and tenths to several ng with the fluorometer. Qualitative analysis was done chromatographically and confirmed by UV spectroscopy and mass spectrometry. The substances were determined by the methods of standard addition and internal normalization. The standard deviation of a determination was ⩽4.2% (relative). The HPLC analysis was used to determine growth hormones of the indole type in extracts from cultures of soil bacteria.

Analysis of ergot alkaloids by high-performance liquid chromatography : II. Cyclol alkaloids (Ergopeptines)

Abstract A high-performance liquid chromatographic method has been developed for the separation and quantitative analysis of a mixture of cyclol ergot alkaloids. The method utilizes silica gel treated with alkylamine (LiChrosorb NH 2 ) as the stationary phase, and isocratic and gradient elution with diethyl ether—ethanol as the mobile phase. Individual alkaloids are detected with a UV detector and determined using the method of internal normalization.

Analysis of the polysaccharides of some soil bacteria by gas chromatography

Abstract A method for the determination of the composition of the extracellular polysaccharides of some soil bacteria by gas chromatography was worked out. Monosaccharides originating from the hydrolysis of polysaccharides were separated as trimethylsilyl derivatives. In addition to the main components, α- and β- d -glucose, d -galactose and d -mannose, other hexoses and pentaoses, d -fructose, 6-deoxy- l -mannose, d -ribose, d -xylose and uronic acids, i.e. d -glucuronic, d -galacturonic and d -mannuronic acids, could be detected in the extracellular polysaccharide. Composition of the extracellular polysaccharide was determined in several species of soil bacteria, including Achromobacter delicatulum, Pseudomonas desmolyticum, Xanthomonas phaseoli var. fuscans and Azotobacter chroococcum.

β-cyclodextrin as a selective agent for separation of selected aromatic acids by high-performance liquid chromatography

Abstract β-Cyclodextrin, as a selective component of the mobile phase or as a chemically bonded stationary phase, was used as an alternative to isocratic high-performance liquid chromatographic separation of structural isomers of some biologically important hydroxy-, methoxy- and amino-substituted aromatic carboxylic acids. The effect of the composition and the pH of the mobile phase on the separation of aromatic carboxylic acids was investigated. The two systems were compared and their selectivity and separation mechanism are discussed.

Effect of aeration on ethylene production by soil bacteria and soil samples cultivated in a closed system

SummaryEthylene production was studied in shaken cultures ofPseudomonas putida andPseudomonas fluorescens isolated from soil and in unsterile garden soil samples moistened to 60% of the water holding capacity. The highest ethylene accumulation in bacterial cultures was reached under conditions of delayed aeration,i.e. when the culture was closed and the aeration started after the oxygen content decreased to 4%. The ethylene production rose immediately after the beginning of aeration. Under these conditions ethylene production was inP. fluorescens 2–3 times and in glucosecultivatedP. putida 6 times higher than in the fully aerated cultures. Methionine stimulated ethylene production byP. fluorescens, whereas glucose proved to be more suitable forP. putida. This strain was incapable of growth on methionine as the sole carbon source. Samples of nonsterile garden soil produced the highest amounts of ethylene under anaerobic conditions. Artificial inoculation of soil samples byP. putida resulted in an increase of ethylene formation in samples with delayed aeration. Addition of glucose or glucose with methionine stimulated ethylene production in all soil samples.

Isolation and separation of new natural lactam alkaloids of ergot by high-performance liquid chromatography☆

Separation of lactam derivatives of ergotoxine alkaloids, of which to were newly isolated from natural material, by high-performance liquid chromatography is described. The separation method utilizes LiChrosorb NH2 as a stationary phase eluted with diethyl ether-ethanol (96:4) as a mobile phase. Alkaloids are detected with a UV detector. The proposed names for the studied lactam derivatives are ergocristam, ergocristinam, erogocornam, ergocorninam, ergocryptam and ergocryptinam.