Cultivation study of Lithospermum erythrorhizon to obtain “Shikon” as a purple dye and traditional medicine – root growth and shikonin derivatives content

“Shikon” is a traditional dye that has been used to dye clothing purple for over a thousand years in Japan. Shikon is also used as a traditional crude drug medicine in Japan and eastern Asia. The purple pigment of Shikon is mainly composed of shikonin and its derivatives (napthoquinone compound). Shikonin and its derivatives have been shown to possess many medical properties, including wound healing, anti-inflammatory, antioxidant. Shikon is made from the root of Lithospermum erythrorhizon (“Murasaki” in Japanese plant name), a perennial herb distributed in Japan and eastern Asia. The root of L. erythrorhizon is reddish dark brown, and contains rich purple pigment. Currently, there are very few wild habitats in Japan for L. erythrorhizon. The extinction of wild L. erythrorhizon is threatened, and conservation activities are being carried out. Therefore, sustainable cultivation is required to stably supply high-quality Shikon. In the last few decades, some cultivation studies have been attempted. However, the cultivation of the plant is very difficult and sufficient results have not been obtained. We tried cultivation study of L. erythrorhizon in Hokkaido, which has the coolest climate in Japan. L. erythrorhizon was cultivated in ten fields in Tobetsu Town, and the amount of root growth and the content of shikonin derivatives were examined. The dry weight of the root of 2-year-old plant reached 35.91 g. The highest acetyl-shikonin content in 2-year-old plant root was 0.56%. Cultivation and production of the perennial herb L. erythrorhizon was possible in one or two years.