Being that it's native to Southern Asia, most people associate the Dimocarpus longan plant as being Chinese. Indeed, it's popular there for its use in herbal medicine. They call it "dragon eye" which is what the word translates to in the Chinese language.For this ORAC test, researchers used longan puree which had about 82% moisture. How much antioxidants it has is low, but then again so are most tropical fruits. The dried longan you buy in a bag should have higher antioxidant content, since most of the water has been removed and hence, a higher concentration of the active compounds.
Research Support, Non-U.S. Gov't: Total antioxidant activity and fiber content of select Florida-grown tropical fruits. J Agric Food Chem. NIH 2006