Abstract
Q-Tempe (quinoa fermented with Rhizopus oligosporus) was far richer in indigestable protein and soluble dietary fiber (SDF) than quinoa (Chenopodium quinoa), a pseudo-cereal in the Andes. The serum cholesterol-reducing actions of Q-tempe and quinoa were investigated in rats in respect of their indigestable protein, SDF and hepatic cholesterol 7α-hydroxylase activity. Although both quinoa and Q-tempe showed serum cholesterol-reduction and acceleration of fecal steroid excretion, these actions by Q-tempe were higher than those by quinoa. The rats fed with Q-tempe showed greater cecal content and short chain fatty acids (SCFAs) produced from SDF, together with higher cholesterol 7α-hydroxylase activity than the rats fed with quinoa. The cholesterol-reduction by Q-tempe could be attributed to the total effect from the inhibition of steroid reabsorption by the indigestable protein and SDF in the small intestine, and the acceleration of cholesterol catabolism by cholesterol 7α-hydroxylase and inhibition of cholesterol synthesis by SCFAs, in the liver.
