title: [Kooroo color: 90-day dietary toxicity study in F344 rats].
abstract: A subchronic toxicity study on kooroo color was conducted using F344 rats of both genders. Kooroo color is an extract of yam root, Dioscorea matudai Hayata, of which the major components are known to be flavonoid pigments. Use of kooroo as a food color is permitted by the Food Sanitation Law in Japan, but the chronic toxicity has not been evaluated in the literature. Rats were fed the product of kooroo color (PKC) at doses of 0.5%, 1.50%, and 5.0% in basal powder diet, while control groups received PKC-free basal diet, for ninety days. A vehicle control given propylene glycol (PG) alone, at the same dosage that the 5.0% group received, was included, because PKC used in this study contained ca. 80 percent PG, used as an extractant during the manufacturing processes. Daily observation of general behavior, and weekly measurement of body weight as well as food consumption were performed. Hematological, serum biochemical and anatomopathological examinations were conducted at the end of administration. No abnormalities ascribable to the treatment with PKC or PG were noted in any examination in this study. Hence, dietary intake of 5.0% of PKC, i.e., 2,993 mg/kg/day for males, and 3,376 mg/kg/day for females, as a mean daily intake for 90 days, had no observable adverse effect in F344 rats. Therefore, kooroo color has no significant general toxicity, and its toxicity, if any, is of a very low order.
authors.affiliation: National Institute of Health Sciences: 1-18-1, Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Sekita
authors.forename: Takashi
authors.initials: T
authors.lastname: Umemura
authors.forename: Minoru
authors.initials: M
authors.lastname: Saito
authors.forename: Yukio
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Katsunori
authors.initials: K
authors.lastname: Ueno
authors.forename: Toyozo
authors.initials: T
authors.lastname: Kaneko
authors.forename: Osayuki
authors.initials: O
authors.lastname: Uchida
authors.forename: Yuko
authors.initials: Y
authors.lastname: Matsushima
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Kawasaki
authors.forename: Tohru
authors.initials: T
authors.lastname: Inoue
mesh_terms: D000818:Animals; D027742:Dioscorea; D005505:Food Coloring Agents / Q000633:toxicity*; D028321:Plant Preparations / Q000633:toxicity*; D018517:Plant Roots / Q000737:chemistry; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D005505:Food Coloring Agents; D028321:Plant Preparations