Esculin, Anti-inflammation, Anti-bacteria, Anti-cancer, Ease pain, Anti-arrhythmic, Anti-histaminic, Anti- cruor Esculin is a glycosidecomposed of glucose and a dihydroxycoumarin compound. Esculin is a product of a coumarin derivative extracted from the bark of flowering ash (Fraxinus ornus). Esculin is used in the manufacturing of pharmaceuticals with venotonic, capillary- strengthening and antiphlogistic action similar to that of Vitamin P. Esculin is a fluorescent dye that can be extracted from the leaves and bark of the horse chestnut tree. You''ll need to shine a black (ultraviolet) light on the indicator to get the full effect. Esculin changes from colorless at pH 1.5 to fluorescent blue at pH 2. The main pharmacological actions of esculin include capillary protection and the inhibition of enzymes such as hyaluronidase and collagenase. Esculin improved skin vasculature and is effective in the management of cellulitis.