Comparisons of effects of raw and gelatinized sago and tapioca starches on serum and liver lipid concentrations in rats.

Abstract

Effects of raw and gelatinized sago and tapioca starches on serum and liver lipid concentrations were compared in rats fed a cholesterol-enriched diet. Total serum cholesterol and the atherogenic index in the rats fed raw sago starch showed a statistically significant decrease and tendency to decrease, respectively, when compared with those of rats fed raw tapioca starch. Both the serum total cholesterol and atherogenic index in the rats fed gelatinized sago starch showed a tendency to decrease when compared with those of rats fed gelatinized tapioca starch. Serum triacylglycerol concentrations in the rats fed raw sago starch were significantly lower than those in the rats fed raw tapioca starch. The apparent digestibility of raw sago starch was lower than that of tapioca starch. The oval shapes of undigested raw sago starch granules collected from feces remained almost unchanged in shape, but had some holes and scrapes on their surfaces. The shape surfaces of undigested raw tapioca starch collapsed, thereby not retaining their original granule shapes. On the other hand, the amylose contents in the raw and gelatinized sago starches were higher than those in the raw and gelatinized tapioca starches. These results suggested that a decrease or a tendency to decrease in serum total cholesterol levels and atherogenic indexes in raw or gelatinized sago starch-fed rats compared to those of raw or gelatinized tapioca starch-fed rats, and a decrease in serum triacylglycerol concentrations in raw sago starch-fed rats compared to those of raw tapioca starch-fed rats, were due to the lower digestibility and higher amylose content of sago starch.