Increasing the Production of Nattokinase and Vitamin K2 in Natto with Dipicolinic Acid
Hiroyuki Sumi*, Shiori Ikeda, Tadanori Ohsugi
Identifiers and Pagination:Year: 2009
First Page: 10
Last Page: 14
Publisher Id: TOFSJ-3-10
Article History:Received Date: 17/7/2008
Revision Received Date: 25/11/2008
Acceptance Date: 5/12/2008
Electronic publication date: 2/4/2009
Collection year: 2009
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
It was found that when dipicolinic acid is added to the culture solution of Bacillus subtilis natto, the area of fibrin dissolved by nattokinase (standard fibrin plate) and the amidase activity of nattokinase against Suc-Ala-Ala-Pro-PhepNA increased. For example, when manufacturing natto using steamed soybeans, the addition of 10-64 mM of dipicolinic acid increases amidase activity by more than 10 times.
The concentration of vitamin K2 (menaquinone-7) also increased by about 4 times with the addition of 10 mM of dipicolinic acid. No other food contains such a high concentration of vitamin K2. The results were the same for the shaking culture as well as for the stationary culture. If the concentration of dipicolinic acid is appropriately controlled, a product with excellent levels for both nattokinase activity and vitamin K2 concentration could be manufactured.