The effect of crude diosgenin extracts from purple and yellow greater yam (Dioscorea alata L.) tubers on blood lipid profile and fecal cholesterol was studied. Tweny four male Wistar rats were divided into 4 groups: normal group and 3 dyslipidemia groups. Two dyslipidemia groups were administered by crude diosgenin extract from purple and yellow greater yam separately, and one group without administration. The crude diosgenin extracts were orally force-fed at a dose of 88.4 mg/kg body weight for 4 weeks. The results showed that crude diosgenin extracst from purple and yellow greater yam improved blood lipid profiles, but did not affect body weight gain. Diosgenin had a role to inhibit cholesterol absorption that indicated by higher fecal cholesterol in treated groups. Crude diosgenin extract from purple greater yam exhibited better lipid profile improvement than crude diosgenin extract from yellow greater yam, indicated by lower total cholesterol, triglyceride, low density lipoprotein (LDL)-cholesterol, and higher high density lipoprotein (HDL)-cholesterol after 4 week treatment. Crude extract of purple water yam also had better inhibition of cholesterol absorption. In clonclusion, both crude diosgenin extracts from greater yam increased fecal cholesterol secretion and improved blood lipid profiles.
Key words: diosgenin, dyslipidemia, fecal cholesterol, greater yam, lipid profile