1. National Research Institute of Brewing, 3-7-1, Kagamiyama, Higashihiroshima 739-0046, Japan.
2. Corresponding author. Mailing address: National Research Institute of Brewing, 3-7-1, Kagamiyama, Higashihiroshima 739-0046, Japan. Phone: +81-82-420-0812. Fax: +81-82-420-0803. E-mail: okuda@nrib.go.jp
3. Department of Applied Biological Science, Faculty of Life Science and Biotechnology, Fukuyama University, 1, Sanzo, Gakuen-cho, Fukuyama 729-0292, Japan.