Skin external agents, including flavanones derivatives

In defect site of the skin typified by large wrinkles and wounds, in order to enhance the tissue regeneration ability of a living body, such as collagens production ability of fibroblasts present in the dermis, enable flavanone derivatives such as farrerol skin external preparation used as a component. Also, a substance excellent effect to promote wound healing for efficient screening, using wound model of skin testing reconstruction action of collagen fiber bundles.