Hypocholesterolaemic non-starch polysaccharide from sugar beet

Abstract

In four feeding trials with male Wistar rats the influences on serum cholesterol of several preparations of non-starch polysaccharide (NSP) from sugar beet were determined. These include a commercial product called Beta-fibre, hot water insoluble and soluble sugar-beet NSP (both pectic and hemicellulosic fractions) and a commercially developed pectic-hemicellulosic sugar-beet NSP called Fibre N. Animals were fed basal diets, both low and high in cholesterol, and intake was limited to circa 80% of ad libitum. The influence of ∼80 g NSP per kg basal diet administered for 28 days was compared with a cellulose control. In one feeding trial the basal low-cholesterol diet was made high in butter fat (230 g per kg). As with ad libitum fed rats reported in the literature, the serum cholesterol concentration did not increase on increasing the saturated fat intake, but doubled when a mixture of cholesterol and cholic acid was added to the diet. Soluble NSP from sugar beet, but not insoluble NSP, was found to be mildly hypocholesterolaemic. The hypocholes-terolaemic effect with Fibre N in the high cholesterol diet was accompanied by a marked (54%) decrease in serum low density lipoprotein cholesterol concentration and a maintained high density lipoprotein cholesterol concentration, whereas in the low-cholesterol diet the high density lipoprotein cholesterol concentration was decreased significantly and total cholesterol was unchanged. Hypocholesterolaemia with sugar-beet NSP did not depend on a decrease in the intake of food, but a change in feeding behaviour was observed. Information was also obtained on other factors which might affect the serum cholesterol concentration including the site of blood sampling, the fed—fasting state of the animals, inter-trial variation, and covariation between pre- and post- NSP treatment cholesterol concentrations.