Angiotensin 1-Converting Enzyme Inhibiting Activity of Aminoethylphosphonic Acid-Containing Phosphoproteins of Edible JUMBOTANISHI, Ampullarius urceus

Author describe a method of extraction and partial purification of phosphoproteins from Jumbo-tanishi, Ampullarius urceus. The extraction of the phosphoproteins was carried out with 0.02M NaHCO3 solution containing 5% NaC1. The Jumbo-tanishi Ampullarius urceus contained two kinds of phosphoproteins in the nondialysate of the alkaline soluble extracts, a kind of phosphoprotein in the dialysate of alkaline soluble extracts of tissue and a kind of phosphoprotein in the alkaline soluble extracts of egg. The amino acid compositions of the each phosphoproteins of the alkaline soluble extracts were characterized by relatively high percentage for glutamic acid, aspartic acid, glycine, alanine and leucine. The phosphono-compounds was found in the all phosphoproteins of the tissue and egg. It has been demonstrated that the peak 1, 2, 3 and 4 contained the phosphonoproteins and that about 12%, 21%, 37% and 47% as phosphonate-phosphorus of total phosphorus. The inhibition of angiotensin 1 converting enzyme (ACE) by the all phosphoproteins was investigated in vitro. The IC50 values of p-1, p-2, p-3 and p-4 of phosphoproteins for ACE were 2.72, 0.89, 1.73, and 0.59, respectively. The most active peak-4 was found in the dialysate of alkaline extract of egg and showed 0.59 (mg protein/ml) inhibition against ACE at IC50 value