Yoroku: The historical value of mold and its now tarnished image

"Kiku Sensei" and "Kiku Shusai" (scholar Kiku) are alternative names for a type of sake that was drunk in China in the deep past. The kanji for "kiku" can also be read as "koji" in Japanese. It refers to a preparation obtained by growing a type of mold on rice and other grains. You can tell how much koji had been praised in old China. Using koji to brew sake, miso, soy sauce and other items is a form of culture unique to East Asia, and is something to be proud of.

Koji itself has been used in the past as a Chinese herbal medicine. The Ming dynasty medical compilation "Bencao gangmu," referred to in English as "Compendium of Materia Medica," mentions several types of koji. Japanese chemist Jokichi Takamine, known for his discovery of adrenaline, produced the digestive enzyme Taka-Diastase from koji 130 years ago, and it is still in use today.

"Beni-koji" produced on steamed rice, also known as red yeast rice, has been used to make alcohol and seasonings in southern China's Fujian Province, among other places. Known for its red color, it was passed on to Okinawa, where it gave rise to the traditional cheeselike dish "tofuyo." Additionally, Dr. Akira Endo won the Lasker Award for discovering statins, drugs with cholesterol-lowering properties that use beni-koji mold.

Recently there has been a stream of reports of kidney disease and other ailments among people using supplements containing beni-koji. Deaths have also been reported, with a causal relationship suspected. This no doubt comes as a shock to those who hoped the supplements would be effective in preventing lifestyle-related diseases.

Furthermore, it took time for a public announcement to be made after the supplements' manufacturer, Kobayashi Pharmaceutical Co., became aware of the situation. The drugmaker also sells the raw ingredients, and chaos has spread, with Japanese and Taiwanese manufacturers that have received supplies urgently announcing voluntary recalls of their products.

We don't want to imagine that there is a problem with beni-koji itself, which has been used for such a long time, but until matters are cleared, it will remain difficult for people to try the red yeast. Japan, a brewing kingdom that has produced renowned "koji professors," urgently needs to investigate the cause of the ailments and restore the tarnished image of "koji," a pillar of its traditional food culture.

("Yoroku" is a front-page column in the Mainichi Shimbun.)