Über die Alkaloide vonAspidosperma discolor A. DC.

Summary From the root-bark ofAspidosperma discolor A.DC., reserpiline, isoreserpiline and isoreserpiline--indoxyl have been isolated as well as two new methoxyindole alkaloids (AD IV and AD VI), which have been partially characterised.     

Über Betacyane,die stickstoffhaltigen Farbstoffe der Centrospermen. Vorläufige Mitteilung

Summary A micro-examination of the hydrolyzed redviolet pigments of some centrospermae families, calledbetacyanins, led to the conclusion that they are derived from betanidin and isobetanidin, and are thus all nitrogenous.

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HerrH. Dietrich leistete wertvolle Hilfe in den ersten Phasen dieser Arbeit. Die untersuchten Pflanzen wurden uns grösstenteils aus dem Botanischen Garten der Universität Zürich und aus der Zürcher Sukkulentensammlung zur Verfügung gestellt. Diese Arbeit wurde in grosszügiger Weise von der FirmaF. Hoffmann-La Roche & Co. AG., Basel unterstützt. Eine ausführliche Beschreibung der Resultate wird in Helvetica Chimica Acta erscheinen.     

Über die Basizität der Knochenmineralien

Summary Interpretations regarding the structure of the bone mineral, based on quantitative data as to the basicity of calcium phosphate, have been complemented by X-ray and electron microscopic investigations. The chemical nature of the bone material is thereby thought to be substituted apatite.

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Ergänzende Bemerkungen zur Arbeit vonJ. Raaflaub, Exper.17, 443 (1961).     

Über die Wasserdurchlässigkeit von Hydrogelen

Summary The permeability of different jellies is measured under various conditions. This property may be of value for the structural analysis of these systems.     

Über die Basizität der Knochenmineralien

Summary The inorganic salts of bone tissue are, owing mainly to their contents of tertiary phosphate, strongly basic. A quantitative evaluation of these base equivalents can be performed through simple titration with acid after solution of the bone salts in a chelating agent (e.g. citrate). Referring to an endpoint of pH 7.40, one finds that per mMol Calcium 0.82 mEq base is set free. With regard to acid-base metabolism, the results indicate that bone phosphate, whichin vivo can be mobilised through osteoclastic resorption, forms a remarkably big base reserve in the animal organism.

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Die vorliegende Arbeit wurde mit der Unterstützung des Schweiz. Nationalfonds zur Förderung der wissenschaftlichen Forschung durchgeführt.     

Über die Fettsäuren aus Spinatchloroplasten

Summary The fatty acids of two samples of chloroplasts fromSpinacia oleracea have been investigated quantitatively. They contain many polyenoic fatty acids (more than 70% of the total fatty acids); amongst these, a relatively high content of C¹⁶-trienoic acid is remarkable. Moreover, the presence of the ³-trans-hexadecenoic acid, recently detected in plants, is noteworthy.     

Über die antithyreotoxische Wirkung der Pantothensäure

Summary Administration of calcium pantothenate to white rats in daily doses of 50–100 mg improved the signs of experimental thyreotoxicosis and decreased the metabolic rate.     

Über die Membransubstanzen vonChlorochytridion tuberculatum W. Vischer

Summary The membrane ofChlorochytridion tuberculatum (nov. gen., nov. spec.) W. Vischer is analyzed by X-ray spectrography. Cellulose, quartz, and calcite are detected. It is remarkable that quartz, which does not crystallize under physiological conditionsin vitro, is formed in the cell wall ofChlorochytridion.     

Über die Herkunft der Isovaleriansäure im Magnamycin

Summary L-Leucine is the precursor of the isovaleric acid in magnamycin, as could be demonstrated withL-Leucine-[U-¹⁴].

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IX. Mitt. Zur Biogenese der Makrolide. VIII. Mitt.W. Hofheinz, H. Grisebach undH. Friebolin, Tetrahedron, im Druck.     

Über die Molekulargrösse des Hämovanadins

Summary The red-brown haemovanadin which is contained in the haemolysate (Henze Solution) of blood cells of the ascidiaPhallusia mamillata Cuvier is a chromoproteid with trivalent vanadium as the central atom and sulphuric acid bound coordinatively. It is found to have a molecular weight of 24,400±1,900 according to the estimation of the diffusion coefficient (D_5°=6.87±0.2 · 10^–7 cm² · s^–1 at pH 2.5–2.8).

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Dem Entdecker des Hämovanadins zum 80. Geburtstag gewidmet.     

Über die Aktivität der Tyrosinase in Tabaksamen

Summary Water or buffered extracts from tobacco seeds (Mont Calme brun) showed both cresolase and catecholase activity of tyrosinase, which was inhibited by 10^–2 M thiourea. No difference of activity could be observed in extracts from old and fresh seeds. Unexpectedly, chlorogenic acid is not oxidized by this tyrosinase.     

Über die Oxydation ungesättigter Fettsäuren durch Pflanzensäfte

Summary Extracts from various parts, including root nodules, of different leguminous plants, and extracts from leaves of several other plants (belonging toSolanaceae andLabiatae) are able to accelerate efficiently the oxidation of unsaturated fatty acids.     

Über die Abhängigkeit der photodynamischen Wirkung von der Intensität der UV.-Bestrahlung

Summary (1) The relation between photodynamic effect and intensity of ultra-violet radiation was investigated by means of the lethal-curve of yeast cells treated with benzpyrene as photosensibilizer.(2) If the dosis of radiation ist kept constant, the resulting photodynamic effect decreases rapidly with diminishing intensity.

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Teilergebnisse der Dissertation.     

Über die Grenzen der metabolischen Adaptationsfähigkeit vonAspergillus niger

Summary The ability ofA. niger to assimilate malonic acid, which we consider to be the way both of obtaining energy (citric acid cycle) and of synthesizing cell substances (glyoxylic acid cycle), is reduced by substitution. While methyl malonic acid is quickly assimilated and ethyl malonic acid more slowly propyl-, dimethyl-, and diethyl malonic acid cannot be used by already formed molds.