Anti-inflammatory effect of foods and crude drugs in relation to bitter and spicy tastes

Backround: In Kampo medicine as well as traditional Chinese medicine, each crude drug is classified by four properties (cold, cool, warm, and heat), five tastes (sour, bitter, sweet, spice, and salt) based on the Yin-yang and five elements (wood, fire, earth, metal, water) theory. The four properties and five tastes are greatly related to the medicinal efficacy of the crude drug in Kampo medicine. The pharmacological function of crude drugs is called "Yakuno" in Japanese. Examples of Yakuno include various functions such as clearing heat and removing blood stasis. Crude drugs with properties classified as cold or cool have the function to clear heat as they cool the body. Crude drugs classified as bBitter also have the function to clear heat. We speculated that anti-inflammatory constituents are included in crude drugs and food that are classified as cold or cool in property and bitter in taste.Keywords: crude drug, Kampo medicine, food, property, taste, nitric oxide, inflammation, pharmacological function