discovery_imgAjoene (pron.: /ˈɑːhoʊ.iːn/) was not discovered until in the 80s. In 1983, Apitz-Castro from Venezuela and other colleagues such as Jain from the University of Delaware discovered a methanolic extract from garlic homogenate as an effective antiplatelet agent. They reported that the garlic extract contains 2-vinyl-4H-1,3-dithiin and an unknown compound. A year later, Block worked in close collaboration with the same group of scientists to uncover the unidentified compound from the methanol extract as ajoene [(E,Z)-4,5,9-trithiadodeca-1,6,11-triene-9-oxide], ajo’ is Spanish for garlic, which exists in two isomers.

In the same year, Block and Ahmad developed the oil maceration procedure to extract ajoene. Chopped garlic pieces were soaked in methanol at 25ºC for 48 hours; the concentrate was suspended in water and was extracted with diethyl ether. The extract was concentrated, and the residue was stored at 25ºC for 4 days as a 10% solution in methanol, filtered, and concentrated giving yellow oil. The oil was then purified to obtain ajoene (Apitz-Castro et al, 1983; Block et al, 1984; Block, 2010