European Journal of Nutrition (v.19, #2)

Glucose isomerase was produced fromStreptomyces phaeochromogenes by aerobic fermentation at 28 °C for 24 hrs. The crude enzyme was obtained by disintegrating the harvested cells. It was found that ammonium sulphate at a saturation of 0.3–0.5 gave the maximum enzyme recovery (88.8%) from the crude extract, while acetone gave 66.2% at a concentration of 3/1 (V/V). On this basis the crude enzyme extract was purified following several steps as concentration, dialysis, precipitation with (NH4)2 SO4, then passing through column of Amberlite CG-50, and the eluate was treated with acetone to precipitate the enzyme.The kinetics behavior was studied and it was found that: optimum D-glucose concentration was 0.8 M, Km was 0.25 M, optimum pH was 7.0 and temperature was 70 °C. Magnesium at concentration of 0.07 M gave the maximum activity and its Km was 0.024 M. Antagonistic effects of Na+, Ca++ and Fe+++ in presence of 0.07 M of Mg++ were studied.Km and Vmax at different levels of Mg++ concentration were determined and no change in Km value was observed, while Vmax was affected. These findings indicate that the Mg++ combined with enzyme independently of the substrate.

Der Artikel enthält Literaturangaben über die biologische Wirkung, Toxizität im Tierversuch und die Verwendung von Xylit bei der Behandlung des Diabetes mellitus sowie von Störungen des Leber-Galle-Systems.Auf Grund der Ergebnisse der Untersuchungen des Pharmakologischen Komitees des Gesundheitsministeriums der UdSSR wurde Xylit für die Ernährung und die pharmakologische Verwendung zugelassen. Xylit wird durch Hydrolyse von Pflanzenmaterial hergestellt. Die Verbraucher erhalten das Xylit hauptsächlich durch die Lebensmittelindustrie (Zusatz von Xylit zu Candies und eingedosten Früchten).

The intravenous injection of zinc chloride immediately before and 15 minutes after alloxan or dithizone prevented the usual hyperglycaemia observed 24 hours after induction of diabetes. The intravenous injection of manganese chloride prevented any marked rise of blood glucose, while chromium and cobalt chlorides lowered the blood glucose level to a certain extent.In alloxan diabetic rats, serum GOT and GPT levels were significantly higher than normal. The serum GOT levels were higher in animals injected with chromium than cobalt, zinc and manganese; while serum GPT levels were higher in cobalt than in chromium, zinc and manganese. In dithizone diabetes, serum GOT and GPT were increased in animals injected with cobalt than chromium, zinc and manganese.Alloxan diabetic rats showed lower serum alkaline phosphatase levels and higher in animals injected with cobalt than chromium, zinc and manganese. For dithizone, there are statistically significant differences in all cases.In alloxan diabetes, coeruloplasmin was higher than normal, while intravenous injection of dithizone was without effect on serum coeruloplasmin.

Radiation-induced aggregation of protein in aqueous solutions was studied. Different concentrations of casein solutions have been irradiated as such or in the presence of carbohydrate and/or lipid. Gel chromatography data indicated a close relation between the amounts of aggregates and protein concentration. Protein aggregation increased with the increase in radiation dose level. The addition of carbohydrate (trehalose) reduced the amount of radiation-induced aggregates, whereas the sole addition of oil caused an induction in protein aggregation when the solution was irradiated at 1 Mrad. However, insignificant changes in protein aggregation were observed when emulsified oil was added to the casein-trehalose solution.

Unterschiede im postoperativen Stoffwechselverhalten bei prä- und postoperativem Beginn der totalen parenteralen Ernährung by M. Georgieff; R. Kattermann; K. Geiger; L. W. Storz; U. Bethke; H. Lutz (122-139).
In dieser Studie wollten wir den Einfluß einer24stündigen präoperativen totalen parenteralen Ernährung (TPN) —10 chirurgische Patienten, Kollektiv 1 — im Vergleich zum unmittelbaren postoperativen Beginn der TPN — 9 chirurgische Patienten, Kollektiv 2 — auf den postoperativen Stoffwechsel untersuchen. Wahrscheinlich auf Grund präoperativ aufgebrauchter Glykogenreserven bei K 2 nahmen die postoperativen Kohlenhydratverluste im 24-Stunden-Urin wesentlich rascher ab als bei K 1. 45 mMol/l Natrium deckten nicht den postoperativen Bedarf bei K 1. Trotz einer Zufuhr von 90 mMol/l Kalium/24 Stunden war bei einigen Patienten des K 1 eine zusätzliche Substitution notwendig.Bei keinem der Kollektive war eine zusätzliche Phosphatsubstitution erforderlich. Die Flüssigkeitsbilanz war bei K 1 mit Ausnahme einer leicht positiven Bilanz am Operationstag an allen anderen Tagen ausgeglichen. Vom 2. postoperativen Tag an trat bei K 2 ein Defizit von freiem Wasser auf. Es konnte in dieser Studie deutlich aufgezeigt werden, daß der postoperative Flüssigkeits- und Elektrolytbedarf durch eine kurze präoperative Flüssigkeits- und Nahrungskarenz stark beeinflußt wird.In this study we intented to investigate the influence of a 24-h-preoperative total parenteral nutrition (TPN) therapy — 10 surgical patients, group 1 — compared with the postoperative beginning of TPN — 9 surgical patients, group 2 — on the postoperative metabolism. Most probably due to preoperatively depleted glycogen storages in G 2, the urinary carbohydrate losses declined more rapidly postoperatively compared with G 1. 45 mMol/l of sodium did not cover the postoperative requirements of G 1. Although we administered 90 mMol/l of potassium/24 h, several patients of G 1 needed an additional substitution. No additional phosphate substitution was necessary in either group. Except for a slight positive balance on the operation day, fluid balance was well balanced on all the other days in G 1. From postoperative day 2 on, G 2 developed a deficit of free water. It could be demonstrated very clear in this study that the postoperative fluid and electrolyte requirements are strongly influenced even by a short-term preoperative fasting period.

Buchbesprechungen by K. Lang; W. Wirths; Dick; H. Glatzel; D. Senczek (140-144).

Mitteilungen (145-145).