Increase in spontaneous locomotive activity in rats fed diets containing Sake lees or Sake yeast

The process of Sake making generates a great deal of secondary product called Sake lees. (Part of the Sake lees is disposed of as waste, so finding ways to recycle it are a matter of concern. Because Sake lees contains many nutritious substances derived from both rice and Sake yeast, we studied the physiological effects of these materials on rats. Sprague-Dawley rats were fed one of three experimental diets for two weeks. Rats fed diets containing either 20% Sake lees or 2% Sake yeast (Kyokai 9 yeast) both had higher spontaneous locomotive activity than rats fed a control casein diet. Body weight and food consumption were not different among the three groups. These results suggest that Sake lees and Sake yeast have a reinforcing effect on spontaneous locomotive activity.