Bacillus natto culture extract

Abstract

A Bacillus natto culture is treated with chitosan, and then filtered, concentrated, and dried. According to this method, a Bacillus natto culture extract containing nattokinase and 1 μg or less of vitamin K2/g dry weight is obtained.

What is claimed is:  
     
         1 . A Bacillus natto culture extract containing nattokinase and 1 μg or less of vitamin K2/g dry weight.  
     
     
         2 . A Bacillus natto culture extract containing nattokinase and 1 μg or less of vitamin K2/g dry weight, obtained by a method which comprises culturing Bacillus natto in a liquid culture medium, and treating the culture medium obtained therefrom with chitosan.  
     
     
         3 . The Bacillus natto culture extract of    claim 1    or    2   , wherein the Bacillus natto culture extract is in the form of a concentrated extract, a paste, a powder, a granule, a capsule, a drinkable preparation or a tablet.  
     
     
         4 . A method for producing a Bacillus natto culture extract containing nattokinase and 1 μg or less of vitamin K2/g dry weight, comprising culturing Bacillus natto in a liquid culture medium to obtain a cultured medium, and treating the cultured medium with chitosan.  
     
     
         5 . A method for collecting vitamin K2, comprising treating a sample containing vitamin K2 with chitosan, and extracting the vitamin K2 adsorbed by the chitosan with an organic solvent.