The quantity of bacteria and ECP arrived at a maximal value at 4% peptone in the medium, and protease production was steady at 2% peptone.

• 培养的菌体量与ECP蛋白含量，在培养基中蛋白胨浓度达4%25时达最高值，蛋白酶分泌量则在蛋白胨浓度为2%25时已稳定。