Proximate and Cardiac Glycoside Composition of Thevetia (Thevetia neriifolia. JUSS) Seed as Affected by Soaking in Water, Brine and Ethanol

Abstract

Effects of soaking using water, ethanol and brine on proximate and cardiac glycoside composition of Thevetia neriifolia seed (TS) were undertaken. Each 100g portion of TS was soaked in either water or ethanol for 24 hours or in 2.5, 5.0 and 7.5% brine solution for 2, 3 or 4 hours. The samples were then either sun-dried for 3 days or toasted after soaking and thereafter analyzed for chemical and residual glycoside composition. There were significant (P<0.05) variations in the composition of ash which ranged from 13.0% in the raw meal (T R ) to 11.04% in T 4 (TS soaked in fine-grade ethanol and sun-dried). Obtained values for nitrogen free extracts was between 12.56% in T 1 (TS soaked in water and toasted) and 28.31% in T 4. These values varied significantly (P<0.05) among the groups except in T 2 (TS soaked in water and sun-dried) (19.47%) and T 3 (TS soaked in fine-grade ethanol and toasted) (20.09%) where the values were similar (P>0.05). Toasting significantly (P<0.05) reduced the crude protein (CP) in water and ethanol treated samples from19.35% in raw sample to 18.14 and 18.43%, respectively. The CP increased significantly in sun-dried water (22.1%) and brine treated (23.1%) samples. Soaking in 7.5% brine for 3 hours significantly (P<0.05) reduced glycoside content from 4.7% to 0.07% (98.51% reduction of glycoside).