Effect of Various Solvent on the Specific Amino Acids of Black Soybean (Glycine soja) Sprout

The objective of this research was to study the effect of various solvent extractions
on the specific amino acids as small peptide or free amino acids that was contained in the
extract after removal of the macromolecule protein of black soybean sprouts. The experimental
design of this research was randomized complete design with one factor, which was the three
various solvent, i.e. hexane, ethanol and water. The black soybean seed was germinated for 36
h. The small peptide and free amino acids of black soybean sprout were isolated at 3 various of
solvents extraction, and then the macromolecule proteins in the extracts were precipitated at the
pH 4. The extracts of black soybean sprout after removal of the macromolecule protein were
analysed by HPLC to determine the profile of amino acids for stimulation of insulin secretion.
The result of this research showed that the extracts contained the small peptide and free amino
acid for stimulation of insulin secretion. The best solvent extraction was water that was due to
the content of Leu, Arg, Ala, Phe, Ile, and Lys of water extract was higher than hexane and
ethanol extracts.