Stability data on natto NKCP
1. Storage Stability
The dried filtrate of B. subtilis natto culture (NKCP Nattokinase) was examined for changes in the content of natto bacillus-produced proteins and peptidase activity during storage. No changes in the content and activity were observed after 6 months of storage at 37ºC or 24 months of storage at room temperature.
Changes in peptidase activity of NKCP powder were ±5% or less when stored at 25ºC or 37ºC for 6 months.
2. Heat Stability
A solution of 1g of NKCP powder in 10ml of 50mM tris–hydrochloric acid buffer (containing 100mM of NaCl, pH 9.0) was used in a heat-stability test for peptidase activity. The NKCP solution, treated under different temperatures and times, was examined for the residual rate of peptidase activity of B. subtilis natto produced protein using a synthetic chromatogenic substrate, S-2251. As shown in the figure below, the peptidase in NKCP was stable when heated up to 60ºC.