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THE separation of vanillin and syringaldehyde produced by the oxidation of lignins with nitrobenzene in alkaline medium is of importance in lignin chemistry. Spruce lignin gives only vanillin1, whereas hardwood lignins give both aldehydes in relative quantities depending on the species2. Only limited success has attended efforts to separate them by chemical means2,3. Separation by vacuum sublimation2 employs 0·4 gm. of the mixed aldehydes and requires specialized equipment. The present communication shows that separation can be effected by paper partition chromatography using petroleum ether saturated with water as the mobile phase.

1. Acrolein was detected in rat liver suspensions incubated in the presence of allyl alcohol and allyl formate. Acrolein was determined by condensation of the distilled aldehyde with semicarbazide, followed by spectrophotometric measurement of the semicarbazone at 257nm and identification by paper chromatography. 2. The transformation of allyl alcohol into acrolein occurred in the presence of NAD+. Inhibitors of rat liver alcohol dehydrogenase inhibited the reaction. 3. It is suggested that the hepatotoxic actions of allyl alcohol and of allyl formate on rat liver are related to their conversion into acrolein.

Carbon-14-labeled 5-hydroxytryptamine (5HT) was administered intraportally to normal and cirrhotic rats, and urine and bile were collected periodically for periods up to 6, and occasionally up to 10 hr. 14C-labeled 5HT metabolites were separated with the use of two-dimensional paper chromatography, and the radioactivity of nine metabolites of 5HT was measured. Cirrhotic rats excreted 14C metabolites into urine in less quantity than did normal rats. In addition, the biliary excretion of 14C-labeled 5HT metabolites was markedly depressed in cirrhotic rats. The preferential occurrence of glucuronide conjugates was demonstrated in both the urine and bile of cirrhotic animals. 14C-labeled 5-hydroxytryptophol conjugates decreased and relabeled 5HT conjugates increased in cirrhotic rats. In normal animals, at least one-third of the 14C-labeled 5HT metabolites excreted into the bile go through the enterohepatic circulation, and a significant proportion of these can be found again in bile after intrajejunal administration of prelabeled bile.

The oxidation of decane by a cell-free particulate preparation from Candida intermedia was studied. Decane is oxidized to decanoate via decanol and decanaldehyde. Oxidation of decane to decanol requires molecular oxygen. Decanol is oxidized to decanaldehyde by a nicotinamide adenine dinucleotide-linked dehydrogenase differing greatly in specificity from ordinary yeast alcohol dehydrogenase. Decanaldehyde is oxidized to decanoate by a nicotinamide adenine dinucleotide-linked dehydrogenase that oxidizes long-chain aldehydes but not short-chain aldehydes. The enzymes that oxidize decane, decanol, and decanaldehyde are all induced when decane is present in the medium. These enzymes are apparently located in the cell membrane.

Reduced nicotinamide adenine dinucleotide phosphate (NADPH)-aldehyde reductase was isolated in 24% yield and 66-fold purification from a dl -glyceraldehyde-grown Rhodotorula species. This enzyme was specific for NADPH, and d -, l -, or dl -glyceraldehyde were equally good substrates. Other substrates had activities as follows: methylglyoxal, 50%; fructose, 33%; d - and l -arabinose, 12%; d -xylose, 8%; d -glucose, 5%; d -erythrose and d -threose, 0 to 5%. The product from the reduction of dl -glyceraldehyde was glycerol, as shown by high voltage electrophoresis, paper chromatography, and direct enzymatic analysis. Kinetic studies gave K m values of 0.89 m m and 0.013 m m for dl -glyceraldehyde and NADPH, respectively. An optimal p H range of 6.3 to 6.7 was found for maximal activity. Reduction of NADP + by glycerol was not demonstrable. This Rhodotorula NADPH-aldehyde reductase activity was compared to similar enzymes from other sources.

Increased blood viscosity has been shown to be an important factor in reducing blood flow in a review and analysis of the history, clinical findings, and haemodynamic, rheological, radiological, and biochemical measurements in 126 patients with intermittent claudication. In some patients increased viscosity seemed to be the determining cause of claudication. A raised plasma fibrinogen was the most common single biochemical abnormality. The results of conventional serum lipid and lipoprotein estimations were abnormal in the series as a whole but did not correlate with clinical findings or flow measurements at individual patient level. There was, however, a significant correlation between some clinical findings and the susceptibility of the red cells to autoxidation.

Ethylene is a plant hormone with effects on plant growth and development [ 11. Its biosynthesis has been studied by many investigators, and methionine, 2-keto-4-mercaptomethylbutyrate (KMB) or 3-mercaptomethylpropanol (methional) have been proposed as the most likely precursors [2]. The absolute reyuirement for oxygen in the synthesis of ethylene has been pointed out (cf. [l] ). Yang et al. [3-41 and Mapson and Wardale [6] described model reactions, which proposed the involvement of oxygen radicals in ethylene production. Beauchamp and Fridovich [7] could show, that the reactive species in the formation of ethylene from methional in the presence of xanthin and xanthinoxidase was probably the OH-radical. Evidence was provided recently, that illuminated chloroplasts are able to reduce oxygen yielding both H2 O2 [8--l 0] and the superoxide free radical ion O2 .[ 11~ 141. This communication describes the formation ethylene from KMB or methional by illuminated chloroplast lamellae. The results provide evidence, that the OH-radical is active in generating ethylene from the above substrates.

Wild-type strains of Escherichia coli K-12 accumulate toxic concentrations of methylglyoxal when grown in medium containing adenosine 3′,5′-monophosphate and either d -xylose, l -arabinose, or d -glucose-6-phosphate, independent of the presence of other carbon sources. Mutations at a locus called cxm specifically block methylglyoxal formation from xylose in the presence of adenosine 3′,5′-monophosphate. Accumulation in medium containing xylose, studied in some detail, is dependent on the ability to utilize xylose and is associated with an increased rate of xylose utilization without changes in levels of xylose isomerase. These results suggest that adenosine 3′,5′-monophosphate results in induction of excessively high levels of an early rate-limiting step in xylose metabolism. This step may be the transport of xylose into the cell. The resulting excessive rates of xylose catabolism could stimulate methylglyoxal formation by overburdening late steps in glycolysis.

The biosynthesis of the newly isolated polyamine, sym-homospermidine (NH(2)-[CH(2)](4)-NH-[CH(2)](4) -NH(2)), was studied by using radioactive amino acids. Arginine was the most effective precursor, being about 10 times as active as ornithine. Unlabelled agmatine and putrescine markedly inhibited the incorporation of [(14)C]arginine into homospermidine. Similarly the incorporation of ornithine was inhibited by unlabelled arginine and putrescine. gamma-Aminobutyraldehyde, the oxidation product of putrescine, was considered to be one of the intermediates in the biosynthesis of homospermidine. The biosynthesis may involve a Schiff-base formation of putrescine with gamma-aminobutyraldehyde and subsequent reduction. A limited synthesis of spermidine also takes place under these conditions.

1. 3-Hydroxypropylmercapturic acid, i.e. N-acetyl-S-(3-hydroxypropyl)-l-cysteine, was isolated, as its dicyclohexylammonium salt, from the urine of rats after the subcutaneous injection of each of the following compounds: allyl alcohol, allyl formate, allyl propionate, allyl nitrate, acrolein and S-(3-hydroxypropyl)-l-cysteine. 2. Allylmercapturic acid, i.e. N-acetyl-S-allyl-l-cysteine, was isolated from the urine of rats after the subcutaneous injection of each of the following compounds: triallyl phosphate, sodium allyl sulphate and allyl nitrate. The sulphoxide of allylmercapturic acid was detected in the urine excreted by these rats. 3. 3-Hydroxypropylmercapturic acid was identified by g.l.c. as a metabolite of allyl acetate, allyl stearate, allyl benzoate, diallyl phthalate, allyl nitrite, triallyl phosphate and sodium allyl sulphate. 4. S-(3-Hydroxypropyl)-l-cysteine was detected in the bile of a rat dosed with allyl acetate.

SUMMARY: A number of fungi isolated from soils under a variety of vegetational types was found to attack p-hydroxybenzaldehyde, ferulic acid, syringaldehyde and vanillin. These compounds were used as sole source of carbon by the organisms tested. By means of spectrochemical methods and paper chromatography it was shown that vanillin and ferulic acid were converted to vanillic acid before the breaking of the benzene ring, and syringaldehyde was converted to syringic acid. The bearing of these results on the breakdown of lignin in soil is discussed.

The reported occurrence of synergistic false-positive coliform reactions on M-Endo MF medium was investigated. The objectives of the study were (i) to isolate populations of bacteria which produced such false-positive reactions, (ii) to determine whether false-positive sheen reactions are a result of synergistic interaction, and (iii) to determine the metabolic intermediates involved in false-positive sheen production. Samples of river water were subjected to coliform analysis by the membrane filter technique with M-Endo MF medium. Suspect sheen-forming colonies were analyzed to determine purity and identity of cultures. Mixed cultures were separated, and individual isolates were examined for sheen production. The isolates not producing a sheen were recombined and tested further for sheen production. Those mixtures reproducing the sheen were characterized biochemically and tested to determine the metabolic intermediates involved. Chromatographic analysis of the metabolites showed that individual isolates produced an assortment of neutral organic compounds including 2-butanone, 2,3-butanedione, formaldehyde, and butyraldehyde, whereas acetaldehyde or propionaldehyde was produced only by the mixed cultures. Tests showed that both propionaldehyde and acetaldehyde could react to produce a sheen on M-Endo medium. The conclusion was reached that synergistic false-positive coliform reactions do indeed occur on M-Endo MF medium.

The reduction of alpha-aminoadipate to alpha-aminoadipic delta-semialdehyde by a cell-free extract of Saccharomyces is shown to be a three-step process. First the amino acid reacts with ATP to form an adenylyl derivative. Then the adenylyl derivative of alpha-aminoadipate is reduced in the presence of NADPH. In the third step the reduced adenylyl derivative of the amino acid is cleaved to form alpha-aminoadipic delta-semialdehyde. The presence of Mg(2+) is necessary for the first and second steps. The third step does not need any cofactors. The product of the first step was isolated by chromatography after incubating the cell-free extract of Saccharomyces with alpha-aminoadipate, ATP and Mg(2+). The isolated product was identified as an adenylyl derivative of alpha-aminoadipate and could be converted into alpha-aminoadipic delta-semialdehyde under the stated experimental conditions. The product of the second step was too unstable to be identified.

To assess the prognostic significance of clinical and laboratory findings in intermittent claudication a group of 62 untreated patients was followed up in detail for periods of from one to three years. There was a significant correlation between progressive deterioration of the peripheral circulatory disturbance and the initial blood viscosity, the plasma fibrinogen level, and the susceptibility of red cell lipids to autoxidation.

1. Crude gammadelta-dioxovalerate was synthesized from laevulinate by two different methods and was purified by Sephadex chromatography. Some analytical reactions of the compound are described. 2. gammadelta-Dioxovalerate is a substrate for glyoxalase I and the GSH derivative formed by this enzyme is hydrolysed by glyoxalase II to form d-alpha-hydroxyglutarate. The K(m) of glyoxalase I for gammadelta-dioxovalerate is 1.0x10(-3)m at pH5.8.3. The u.v.-absorption spectrum of thiol ester, synthesized enzymically from gammadelta-dioxovalerate and GSH by glyoxalase I, is almost identical with that for S-lactoylglutathione. Some optical properties of this thiol ester were measured. 4. Attempts to show reversibility of the glyoxalase system reactions with d-alpha-hydroxyglutarate as substrate were unsuccessful. 5. The possible metabolic role of the gammadelta-dioxovalerate reaction is discussed. It is suggested that one of the metabolic functions of the glyoxalase system may be to provide a mechanism for the entry of this compound into the tricarboxylic acid cycle.

l -Arabinose was metabolized through an oxidative pathway by extracts of a strain of Rhizobium japonicum . The findings showed that l -arabinose is converted into 2-keto-3-deoxy- l -arabonate, which is cleaved into glycoaldehyde and pyruvate.

Human platelets can be fractionated into three main subcellular components: granules, membranes, and a soluble fraction. In this study we determined the phospholipid and neutral lipid content of the granules and membranes. Quantitative relationships between lipids and protein were examined. The fatty acid and aldehyde composition of individual phospholipids and neutral lipids was also determined. Whole platelets had a lower lipid to protein ratio than did the subcellular particles, but the basic lipid composition of the granules, membranes, and platelets was similar. The phospholipid composition of platelets and subcellular fractions was found to differ only in that granules had a lower percentage of lecithin. Each of the phospholipid classes displayed a distinctive fatty acid pattern which was the same in all fractions and in whole platelets. The major neutral lipid was free cholesterol. Cholesteryl esters, triglycerides, and free fatty acids were minor components. The molar ratio of cholesterol to phospholipid in the platelet membranes was lower than that of brain myelin and erythrocyte ghosts. Some differences in fatty acid composition of the neutral lipids of platelet fractions were found. A special lipid composition or constituent that would correlate with platelet function has not been found.

With horseradish peroxidase as catalyst the main product was dihydroxytartrate, but small amounts of glycolaldehyde, mesoxalic semialdehyde, mesoxalate and possibly glyoxal were also formed. Mn2+ catalysis gave rise only to mesoxalate and oxalate. When oxygen uptake was followed by a manometric method the rate of the peroxidase-catalysed reaction was proportional to oxygen concentration and marked inhibition by cyanide was obtained only at low buffer concentration. The catalytic effects of peroxidase and Mn2+ were almost always additive. Chelating agents inhibited the Mn2+-catalysed reaction, but had either no effect or a slight accelerating effect on the peroxidase-catalysed reaction. It is concluded that Mn2+ does not function as cofactor in the peroxidase-catalysed oxidation.