[The degradation of vicine and convicine in field bean meal by selected bacterial strains]. / Untersuchungen zum Abbau von Vicin und Convicin in Ackerbohnen mehl durch ausgewählte Bakterienstämme.

Vicine and convicine as natural occurring toxic compounds in Vicia faba are involved in the formation of hemolytic anemia (favism). Removal of these compounds needs high technological expense. Microbiological degradation with different strains of bacteria was tried. After 3 h incubation with Streptococcus faeciens convicine was converted completely and Vicine to about 95%.

[Blood pressure monitoring in aged hypertensive patients treated with sustained-release nicardipine or nifedipine]. / Monitoring tensionnel chez des hypertendus âgés traités par nicardipine ou nifédipine à libération prolongée.

In a double-blind parallel study, 20 elderly hypertensive subjects (mean age 85 years) were treated either by nicardipine or by nifedipine in slow-release form for 7 days. Blood pressure was measured by ambulatory, non-invasive daytime monitoring. Efficacy of both drugs was similar on the seventh day of treatment. However, the hypotensive effect induced by nifedipine was maximal on the first day of treatment, in contrast to the progressive effect induced by nicardipine. In 2 cases, marked hypotension was observed after the first tablet of nifedipine.

[Analysis of volatile nitrosamines in food of animal origin]. / Beitrag zur Analytik flüchtiger Nitrosamine in tierischen Lebensmitteln.

A method is described for the fluorescence-spectrophotometric densitometric determination of nitrosamines. For this purpose, foods of animal origin are vacuum-distilled, the distilled-over nitrosamines are extracted with methylene chloride from an acid medium and, after cleavage by hydrogen bromide, the corresponding amines are reacted with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole. The purificaton of the extract and the resolution of the corresponding fluorescent amine derivatives are effected simultaneously by two-dimensional thin-layer chromatography. The determination is achieved by in situ fluorescence spectrophotometry against test substances on the same slab. This method seems useful for investigations into the formation of nitrosamines in foods of animal origin because it permits to detect nitrosamine concentrations as low as 0.1 microgram/kg of food.

[Determination and occurence of aflatoxin M1 and B1 in milk and dairy products]. / Bestimmung und Vorkommen von Aflatoxin M1 und B1 in Milch und Milchprodukten

The described method enables a simultaneous identification and determination of aflatoxin M1 and B1 in milk and dairy products by means of a self-registering fluorescence spectrophotometer with a thin-layer chromatographic accessory, directly from the plate. The semiquantitative estimation on the thin-layer chromatographic plate enables also routine analyses in the hygienic practice. The recovery rates for aflatoxin M1 and B1 in milk are about 83 and 82%, respectively -- the detection limit is about 0.1 microng per kg. The recovery rates for aflatoxin M1 and B1 in milk powder are about 89 and 94%, respectively -- the detection limit is bout 0.5 microng per kg. The reproducibility is given with a standard deviation between +/- 1.1 and 6,3% and a variation coeffecient of 1.3 and 6.7, respectively. 4 of 24 analized samples of commercial winter milk were aflatoxin M1-positive, whereas aflatoxin B1 could not be found. One of the milk powder products, a sample of the infant food, "Ki-Na", made in the GDR, contained, however aflatoxin B1. Aflatoxin M1 could not be found. Food-hygienic-toxicological conclusions are discussed.

Myocardial glucose uptake and breakdown during adenosine-induced vasodilation.

In isolated K+ (16.2 mM)-arrested cat hearts perfused at constant pressure adenosine infusions (0.8 mumoles - min-1 - 100 g-1 for 10 min) caused an increase in myocardial 14C-glucose uptake and release of 14CO2 + H14CO3- AND 14C-lactate simultaneously with a rise in coronary flow. The ratio of the release of 14CO2 + H14CO3- to that of 14C-lactate and the specific activity of lactate in the effuate were not altered. In K+ -arrested hearts perfused with constant volume neither glucose uptake nor glucose breakdown were influenced by 0.8 or 100 mumoles - min-1 - 100 g-1 adenosine with 0.1 - 5 mM glucose in the perfusion medium. It is concluded that adenosine does not affect directly the myocardial glucose carrier system, aerobic or anaerobic glucose breakdown or glycogenolysis, but enhances glucose uptake secondarily by increasing coronary flow. This interpretation is substantiated by the finding that mechanically produced increases in perfusion volume caused similar increases in myocardial glucose uptake as were observed with comparable adenosine-induced coronary flow increments.

[Significance of byssochlamic acid in fruit juice mold]. / Zur Bedeutung der Byssochlaminsäure im Fruchtsaftschimmel

The authors describe a method for the determination of byssochlamic acid in fruit juice. After extraction and purification, byssochlamic acid is separated by thin-layer chromatography on HF 254 silica gel. The quenching of fluorescence of byssochlamic acid is estimated quantitatively on the plate by means of the thin-layer attachment of a fluorescence spectrophotometer using reference substances. For fruit juices the recovery rate is 80%; the limit of detection lies at 0.5 p.p.m. Byssochlamic acid could not be detected in commercially-available fruit juice and neither in juices produced of fruits which had spontaneously got mouldy.