Last Updated: September 28 2022

Dimocarpus Longan (Dragon Eye or Euphoria) is a fruit with limited medicinal use. It does not appear to have a unique composition, but extracts appear quite neuroprotective and may boost cognition.

Longan is most often used for


Longan fruits (Dragon Eye and Euphoria Longan have both been used to refer to Longan fruits) have some traditional usage for alleviating cognitive losses and improving memory. Limited evidence so far suggests this may be true, as oral administration of the fruits to rats appears to exhibit potent neuroprotective effects and has twice been implicated in enhancing cognition.

However, the composition of Longan fruits currently is not remarkable. It is a great source of ellagic and gallic acids, which are potent anti-oxidants; these compounds are not inherently linked to improvements in cognition nor are the Procyanidins or catechins found in Longan. There actually does not appear to be a large amount of compounds known to be unique to Longan fruits, which may be discovered in the future. No bioactive is linked to the cognitive protective or memory enhancing properties.

Beyond that, the polysaccharides appear to be able to interact with the immune system and can act in an immunostimulatory manner. At least one study suggests that the potency is comparable to Ganoderic Acid (from Reishi) but this needs to be replicated; it is another promising avenue.

Other interactions of Longan such as interactions with fat mass, skin quality, or the colorectal cancer interactions are currently unremarkable. There is not enough evidence to suggest Longan fruit as a recommended option for anything although it might be a useful functional food to ingest for cognitive purposes.

What else is Longan known as?
Note that Longan is also known as:
  • Euphoria Longan
  • Dragon Eye
  • Soapberry
  • Dimocarpus Longan

Don't miss out on the latest research

1.^Rangkadilok N, Sitthimonchai S, Worasuttayangkurn L, Mahidol C, Ruchirawat M, Satayavivad JEvaluation of free radical scavenging and antityrosinase activities of standardized longan fruit extractFood Chem Toxicol.(2007 Feb)
3.^Park SJ, Park DH, Kim DH, Lee S, Yoon BH, Jung WY, Lee KT, Cheong JH, Ryu JHThe memory-enhancing effects of Euphoria longan fruit extract in miceJ Ethnopharmacol.(2010 Mar 2)
5.^Sudjaroen Y, Hull WE, Erben G, Würtele G, Changbumrung S, Ulrich CM, Owen RWIsolation and characterization of ellagitannins as the major polyphenolic components of Longan (Dimocarpus longan Lour) seedsPhytochemistry.(2012 May)
6.^Zheng ZZ, Chen LH, Liu SS, Deng Y, Zheng GH, Gu Y, Ming YLBioguided Fraction and Isolation of the Antitumor Components from Phyllanthus niruri LBiomed Res Int.(2016)
7.^Zheng G, Wei X, Xu L, Li Z, Liu G, Zhang XA new natural lactone from Dimocarpus longan Lour. seedsMolecules.(2012 Aug 6)
8.^Okuyama E, Ebihara H, Takeuchi H, Yamazaki MAdenosine, the anxiolytic-like principle of the Arillus of Euphoria longanaPlanta Med.(1999 Mar)
9.^Yang DJ, Chang YY, Hsu CL, Liu CW, Lin YL, Lin YH, Liu KC, Chen YCAntiobesity and hypolipidemic effects of polyphenol-rich longan (Dimocarpus longans Lour.) flower water extract in hypercaloric-dietary ratsJ Agric Food Chem.(2010 Feb 10)
11.^Yi Y, Liao ST, Zhang MW, Zhang RF, Deng YY, Yang B, Wei ZCImmunomodulatory activity of polysaccharide-protein complex of longan (Dimocarpus longan Lour.) pulpMolecules.(2011 Dec 13)
12.^Yi Y, Liao ST, Zhang MW, Shi J, Zhang RF, Deng YY, Wei ZCPhysicochemical characteristics and immunomodulatory activities of three polysaccharide-protein complexes of longan pulpMolecules.(2011 Jul 21)
13.^Jiang G, Wen L, Chen F, Wu F, Lin S, Yang B, Jiang YStructural characteristics and antioxidant activities of polysaccharides from longan seedCarbohydr Polym.(2013 Jan 30)
14.^Jiang G, Jiang Y, Yang B, Yu C, Tsao R, Zhang H, Chen FStructural characteristics and antioxidant activities of oligosaccharides from longan fruit pericarpJ Agric Food Chem.(2009 Oct 14)
15.^Rangkadilok N, Worasuttayangkurn L, Bennett RN, Satayavivad JIdentification and quantification of polyphenolic compounds in Longan (Euphoria longana Lam.) fruitJ Agric Food Chem.(2005 Mar 9)
16.^Hsieh MC, Shen YJ, Kuo YH, Hwang LSAntioxidative activity and active components of longan (Dimocarpus longan Lour.) flower extractsJ Agric Food Chem.(2008 Aug 27)
18.^Lin AM, Wu LY, Hung KC, Huang HJ, Lei YP, Lu WC, Hwang LSNeuroprotective effects of longan ( Dimocarpus longan Lour.) flower water extract on MPP+-induced neurotoxicity in rat brainJ Agric Food Chem.(2012 Sep 12)
21.^Modlin RLLearning from leprosy: insights into contemporary immunology from an ancient diseaseSkin Pharmacol Appl Skin Physiol.(2002 Jan-Feb)
23.^Huang GJ, Wang BS, Lin WC, Huang SS, Lee CY, Yen MT, Huang MHAntioxidant and Anti-Inflammatory Properties of Longan (Dimocarpus longan Lour.) PericarpEvid Based Complement Alternat Med.(2012)
27.^Sheu SY, Fu YT, Huang WD, Chen YA, Lei YC, Yao CH, Hsu FL, Kuo TFEvaluation of Xanthine Oxidase Inhibitory Potential and In vivo Hypouricemic Activity of Dimocarpus longan Lour. ExtractsPharmacogn Mag.(2016 May)
28.^Hsu CP, Lin YH, Zhou SP, Chung YC, Lin CC, Wang SCLongan flower extract inhibits the growth of colorectal carcinomaNutr Cancer.(2010)
29.^Chung YC, Lin CC, Chou CC, Hsu CPThe effect of Longan seed polyphenols on colorectal carcinoma cellsEur J Clin Invest.(2010 Aug)
30.^Panyathep A, Chewonarin T, Taneyhill K, Vinitketkumnuen U, Surh YJInhibitory Effects of Dried Longan ( Euphoria longana Lam.) Seed Extract on Invasion and Matrix Metalloproteinases of Colon Cancer CellsJ Agric Food Chem.(2013 Apr 3)
31.^Ignjatovic V, Ogru E, Heffernan M, Libinaki R, Lim Y, Ng FStudies on the use of "slimax", a chinese herbal mixture, in the treatment of human obesityPharm Biol.(2000)
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