Über die quantitative Trennung neutraler Aminosäuren durch Chromatographie

Abstract

Nr. 4119431 S c li r a m m , P r i m o s i g h. 373gelangen kann. Unter tliesen trmstainden ist die beobachtete Wirkungskonstante natiirlich recht klein uncl betragt der GroBenordnuxig nach:Bei Zuxiahme der Katalysatorkonzentration wird auch in diesem Falle zuuachst eine Zunahme und dann eine rasche Abnahme der maximalen Helligkeit der Luminescenz beobachtet, also ist auch dieser EinfluB qualitativ genau so wie bei der Verwendung der anderen Katalysatoren. Die hier benutzte Versuchsmethode wurde schon in den friiheren Mitteilungen beschrieben. Die Luniinolkonzentration hetrug bei allen Versucheii dieser Arbeit 8 x lo-* Mol/Z. Die Versuche iiber die Inhibitorwirkung wurdeii iinmer bei den optinialen Animoniak-und Katalysatorkonzentrationen vorgenommen. Als maximale Helligkeit der Lumitiescenz -,in relativen Einheitenbezeichnen wir den grogten beobachteten Ausschlag des Galvanometers beini betreffenden Versuch ; dieser kouute gewohnlich unmittelbar nach dem ZusammengieBen der Reaktionsgeniische abgelesen werden. Alu Anfangshelligkeit, die zum Vergleich mit den friiheren Versuchen diente, nurde die Helligkeit nach 20 Sek. Reaktionszeitwieder relativ in Galvanonieteraussclilageiigenonimexi. -Die bexiutzten Katalysatoren waren einfache Kahlbaum-Praparate. Die Liisungen des RuCI, muf3ten ofter frisch bereitet werden, da gealterte Losungen, die hydrolytischen Veranderiingen unterliegen, eine wesentlich geringere katalytische Wirkung zeigten.Hrn. Prof. Dr. J. P l o t n i k o n -danken wir fiir die Lnterstiitzung diescr Xrbtit niit Jfittelxi des Instituts.

A Reinvestigation of Methylguanidine Concentrations in Sera from Normal and Uraemic Subjects

“…Prior treatment of the charcoal with cyanide (Schramm & Primosigh, 1943) did not alter the extent to which conversion of creatinine into methylguanidine occurred under the catalytic influence of the charcoal; when aqueous solutions of creatinine at a concentration of 20 mg/loo ml were subjected to assay, the mean apparent methylguanidine concentration was 2·5 mg/loo ml when cyanide-treated charcoal was employed and 2·6 mg/loo ml when untreated charcoal was used. These values agree well with those obtained when creatinine was added to uraemic serum (Fig.…”

“…of 5% (wjv) urea with I vol. of 0'25% (wjv) a-naphthol (AnalaR; BDH Chemicals Ltd); Sakaguchi reagent No.2, prepared by the addition of 0·7 ml of bromine to 100 ml of 5% (wjv) sodium hydroxide; dry activated powdered charcoal (BDH Chemicals Ltd) washed with dilute hydrochloric acid and treated with cyanide as described by Schramm & Primosigh (1943); creatinine and creatine (BDH Chemicals Ltd), L-arginine and 4-guanidinobutyric acid (Sigma Chemical Co.) methylguanidine sulphate (Kodak Ltd, London), guanidinoacetic acid (K and K Labs. Inc.), guanidinosuccinic acid (Mann Research Labs.…”

Article Commentary: The contributions of Louis I Woolf to the treatment, early diagnosis and understanding of phenylketonuria

“…10 A method for removing phenylalanine and other aromatic amino acids from protein hydrolysates -passage through activated charcoal -had been known since 1943. 11 However, Woolf was the first person to see its relevance to the treatment of PKU, possibly because, before joining the Institute of Child Health at Great Ormond Street Hospital, he had worked on the mass production of casein hydrolysate, with a view to its possible administration as predigested food to severely starved persons in post-war Europe. 12 In 1949 he began to suggest that supplementation of carbontreated casein hydrolysate with appropriate quantities of the missing amino acids (including sufficient phenylalanine to avoid phenylalanine deficiency) would produce the desired low-phenylalanine food.…”

“…Although Gerrard 13 and Bickel and Grueter 19 give one to understand that Woolf attributed his knowledge of the technique to 'a recent report' or 'suggestion' by Block and Bolling, in their 1955 paper 20 Woolf et al cited Schramm and Primosigh's paper of 1943. 11 Block and Bolling mentioned Schramm and Primosigh's paper in the second edition of their book The Amino Acid Composition of Proteins and Foods (1951), 21 but not in the first edition (1945). Woolf probably mentioned Block and Bolling's book simply as the most convenient source for the Bickel group to consult.…”

The Biogenesis of Alkaloids: Xvi. Hordenine Metabolism in Barley

“…The charcoal column was further eluted with 300 ml. of a mixture of water, glacial acetic acid, and phenol in the proportion of 80: 20: 5 (22). This eluate was extracted with ether to remove the phenol and evaporated to dryness under diminished pressure, leaving a residue of aromatic substances (0.198 gm., activity, 5.9X 10" d.p.m.).…”