Flavone - Flavone (English spelling)

Japanese: フラボン - ふらぼん（英語表記）flavone

Flavones are plant pigments that belong to the flavonoid family, and have the structure of phenylchromone, which is the parent skeleton of flavones. Flavones are widely distributed in higher plants, particularly in the form of free or glycosides, and give them a yellow or orange color, but because they are usually pale yellow, their color is often not directly visible in flowers and leaves, as they are hidden by the vivid colors of carotenoids and chlorophyll. Flavones are the most diverse of all flavonoids, and are the origin of the name flavonoid. Apigenin in the petals of dahlias and other flowers, and luteolin in the whole plant of mignonette and the flowers of honeysuckle are representative flavones. Flavonols are flavones that have a hydroxyl group at the third carbon. Chempherol and quercetin, which are widely distributed in the plant kingdom, are pigments of this type, and are pale yellow in their free form, but their glycosides are even more colorless.

[Takao Minamikawa]

"Secondary Metabolism of Higher Plants" by Yoshida Seiichi and Minamikawa Takao (1978, University of Tokyo Press)" ▽ "Plant Metabolic Physiology" by Ishikura Shigeyuki (1987, Morikita Publishing)" ▽ "Healthy Technology of Soybeans" edited by Kawamura Yukio and Okubo Kazuyoshi, supervised by the Japan Food Science and Industry Association (1998, Korin)" ▽ "Asakura Plant Physiology Lectures 2: Metabolism" edited by Yamatani Tomoyuki (2000, Asakura Publishing)" ▽ "Soybean Isoflavones" edited by Yamori Yukio (2001, Saiwai Shobo)"

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

Japanese:

フラボノイドに属する植物色素の一つで、フラボン類の母体骨格であるフェニルクロモンの構造をもつ。フラボンは遊離または配糖体の形でとくに高等植物に広く分布し、黄色ないし橙(だいだい)色を与えるが、普通は、淡黄色のために花や葉ではカロテノイド（カロチノイド）やクロロフィルの鮮明な色調にかくれて直接その色を認められないことが多い。フラボンはフラボノイドのなかでももっとも種類が多彩であり、フラボノイドの名の由来になっている。ダリアなどの花弁のアピゲニンやモクセイソウ全草、スイカズラの花に含まれるルテオリンがフラボンの代表的なものである。フラボンのうち3位の炭素にヒドロキシ基をもつものをフラボノールとよぶ。植物界に分布の広いケムフェロール、クエルセチンがその仲間の色素で、遊離の形では淡黄色であるが、これらの配糖体はさらに無色に近くなる。

［南川隆雄］

『吉田精一・南川隆雄著『高等植物の二次代謝』（1978・東京大学出版会）』▽『石倉成行著『植物代謝生理学』（1987・森北出版）』▽『日本食品科学工業会監修、河村幸雄・大久保一良編著『ダイズのヘルシーテクノロジー』（1998・光琳）』▽『山谷知行編『朝倉植物生理学講座2　代謝』（2000・朝倉書店）』▽『家森幸男編『大豆イソフラボン』（2001・幸書房）』