The Ash (Fraxinus excelsior, L.) is a wind-pollinated deciduous forest tree belonging to the Oleaceae family. It is distributed in Asia Minor and Europe.

Mainly used for furniture construction it has some interesting health properties found in clinical studies: 

• the aqueous extract has shown hypotensive and diuretic actions (1)
• the seed and fruit extract may be useful in metabolic disorders related to impaired glucose tolerance, obesity, insulin resistance and inflammatory status, particularly in the elderly (2)
• the seed extract has the ability to regulate blood glucose and insulinemia, demonstrating anti-obesity effects (3)

Overall, Fraxinus excelsior contains a wide range of chemical components including coumarins, secoiridoids, phenylethanoids, flavonoids and lignans with anti-inflammatory, immunomodulatory, antimicrobial, antioxidant, photodynamic damage prevention, liver protection, diuretic and anti-allergic activities (4). 

In cosmetics, Ash bark extract is used, which is credited with skin regenerating properties due to its antioxidant characteristics.

In the last two decades, ash trees have been dying out almost everywhere in their natural habitat and particularly in Europe due to the fungus Hymenoscyphus fraxineus, transmitted by wind-borne spores, which can, however, be combated by various methods including fungal endophytes or pre-priming of defence responses.

References______________________________________________________________________

(1) Eddouks M, Maghrani M, Zeggwagh NA, Haloui M, Michel JB. Fraxinus excelsior L. evokes a hypotensive action in normal and spontaneously hypertensive rats. J Ethnopharmacol. 2005 May 13;99(1):49-54. doi: 10.1016/j.jep.2005.01.050. 

(2) Zulet MA, Navas-Carretero S, Lara y Sánchez D, Abete I, Flanagan J, Issaly N, Fança-Berthon P, Bily A, Roller M, Martinez JA. A Fraxinus excelsior L. seeds/fruits extract benefits glucose homeostasis and adiposity related markers in elderly overweight/obese subjects: a longitudinal, randomized, crossover, double-blind, placebo-controlled nutritional intervention study. Phytomedicine. 2014 Sep 15;21(10):1162-9. doi: 10.1016/j.phymed.2014.04.027.

(3) Ibarra A, Bai N, He K, Bily A, Cases J, Roller M, Sang S. Fraxinus excelsior seed extract FraxiPure™ limits weight gains and hyperglycemia in high-fat diet-induced obese mice. Phytomedicine. 2011 Apr 15;18(6):479-85. doi: 10.1016/j.phymed.2010.09.010. 

(4) Kostova I, Iossifova T. Chemical components of Fraxinus species. Fitoterapia. 2007 Feb;78(2):85-106. doi: 10.1016/j.fitote.2006.08.002.