[The cholesterol-lowering effect of the unicellular green alga Scenedesmus acutus 276-3a. I. Effect of drum-dried algal material]. / Uber die cholesterinsenkende Wirkung der einzelligen Grünalge Scenedesmus acutus 276-3a. I. Wirkung von walzengetrockneter Algensubstanz.

In three series of experiments hypercholesterolemia was induced in male Sprague-Dawley rats by a 3% cholesterol-enriched diet. The development of hypercholesterolemia was considerably retarded when 20% Scenedesmus powder was incorporated in the diet. In animals fed with standard diet and cholesterol for 6-8 weeks, the average concentration of blood plasma cholesterol increased from 2.0 to 3.6 mmol/l. In contrast, the final concentration reached only 2.4-2.8 mmol/l in animals receiving the cholesterol diet with algae. The plasma cholesterol level in animals receiving only an algal diet did not appear to be influenced. The mean value at the beginning of the test was 2.0 and 2.2 mmol/l at the end. The level of plasma triglyceride in animals fed on algae with and without the addition of cholesterol was lower than that of the controls. The algae-enriched diet prevented an excessive deposition of cholesterol in the liver. The increase in weight of the livers of rats receiving the cholesterol-enriched standard diet and the cholesterol-enriched algal diet were 2.0 and 0.8 g, respectively. The cholesterol content of the livers increased to 600 and 180 mg, respectively.

[The cholesterol-lowering effect of the unicellular green alga Scenedesmus acutus 276-3a. II. Effect of alga fractions]. / Uber die cholesterinsenkende Wirkung der einzelligen Grünalge Scenedesmus acutus 276-3a II. Wirkung von Algenfraktionen.

In former experiments we found that the extent of experimentally induced hypercholesterolemia in male Sprague-Dawley rats was significantly reduced by incorporation of 20% Scenedesmus powder in the diet. This paper reports on the localization of the activity in Scenedesmus powder following extraction of hydrophilic and lipophilic fractions. The fractions obtained by hot water treatment and chloroform-methanol extraction and the remaining extracted algae were incorporated in the standard diet in amounts corresponding to 20% Scenedesmus powder. In animals fed on the standard diet + 3% cholesterol for 6 weeks, the average concentration of blood plasma cholesterol increased from 2.0 to 3.5 mmol/l. The average cholesterol level in animals receiving the different algae extracts + 3% cholesterol amounted to between 2.1 and 2.9 mmol/l. The hot water extracted algae material held the plasma cholesterol levels in cholesterol-stressed animals at normal values. The content of plasma triglyceride in animals receiving the different fractions was lowered by 35-55% in nearly all groups. In cholesterol-stressed animals the excessive deposition of cholesterol in the liver was reduced by untreated algal powder as well as algal material extracted with water or chloroform/methanol. The decrease in liver cholesterol amounted to 50%.