Abstract
Placentaliquid has been graded by alkaline phosphatase activity. Other various components are contained in placenta and several biological activties have been reported. However, the relationship between the biological activities and the components has not been made clear yet.
Storaged Placentaliquid was tested for the preservation ability of the alkaline phosphatase activity. The alkaline phosphatase activity was assayed by the Reiner's method, a modification of the King-Armstrong method. The alkaline phosphatase activity of Placentaliquid was safety preserved at 0°C for 750 days, but the activity was almost declined at 30°C after 230 days.
Placentaliquid was tested for heat stability of the alkaline phosphase and tyrosinase inhibitory activities, Tyrosinase activity was assayed by colorimetric method, a modification of the Lerner's and Shima's method. As the results, 80% of the alkaline phosphatase activity decreased by at 60°C in 60 minutes, while 75% of the tyrosinase inhibitory activity was preserved at 60°C after 60 minutes.
It was considered that the heat inactivation of alkaline phosphatase was due to denaturation of the enzyme protein. On the other hand, the heat inactvation process of the tyrosinase inhibitory activity did not agree to that of the denaturation of the enzyme protein. So the activity of alkaline phosphatase was not closely related to the tyrosinase inhibitory activity. As the above results, it is hardly recognnized that the alkaline phosphatase activity is the most adequate indicator for the grading of Placentaliquid.
