Natural plant enzyme inhibitors. α‐amylase inhibitors in millets

Twelve varieties of sorghum ( Sorghum bicolor ), 14 varieties of pearl millet ( Pennisetum typhoideum ), 12 varieties of setaria ( Setaria italica ), four varieties of ragi ( Eleucine coracana ), 11 varieties of echinocloa millet ( Echinocloa colona ), 13 varieties of proso ( Panicium miliaceum ), 11 varieties of kodo ( Paspalum scorbiculatum ) and 11 varieties of miliare ( Panicium miliare ) were screened for inhibitory activity against human salivary amylase. Echinocloa, proso, kodo and miliare had no detectable activity. Two strains of sorghum and one strain of pearl millet did not show α‐amylase inhibitory activity. All other seeds had activity, the highest being observed in sorghum. Setaria had no action on human, bovine and porcine pancreatic anylases. Sorghum inhibitor did not act on bovine and porcine pancreatic amylases. Pearl millet and ragi extracts inhibited all the four α‐amylases. The inhibitors were non‐dialysable and were inactivated by pepsin treatment. Setaria and sorghum inhibitors were relatively thermolabile compared to ragi and pearl millet inhibitors.