Aesculin

Aesculin occurs naturally in the horse chestnut (Aesculus hippocastanum); aesculin is also found in daphnin, the resin of the common daphne mezereum. Aesculin is a gycosidic coumarin derivative, a colourless, bitter-tasting substance that can be extracted from the bark, leaves and seeds of the horse chestnut (Aesculus hippocastanum). It is hydrolytically split into glucose and the coumarin derivative, its aglycone aesculetin (6,7-dihydroxycoumarin). Aesculin is used together with other horse chestnut substances (e.g. aescin) in vascular medicine (e.g. for thromboses and CVI). The antiphlogistic efficiency of the substance requires further reliable investigations. Aescin is also used in microbiology for the differentiation of bacteria (so-called aesculin cleavage or aesculin hydrolysis).

Like other coumarin derivatives, aesculin fluoresces blue under UV light(UVA range = > 320-400nm, here mainly in the wavelength range around 366 nm). This observation already led to the large-scale production of optical brighteners at the beginning of the 20th century.