Dimocarpus longan. Euphorbia longan, Nephelium longana   龙 眼 肉  Lóng yǎn ròu- "Dragon eye flesh"   Dried Longan aril   Family: Euphorbiaceae   
Commonly known as the longan, is a tropical tree that produces edible fruit. It is one of the better-known tropical members of the soapberry family, to which the lychee also belongs. It is native to Southern Asia. It is called Dragon eye because it resembles an eyeball when its fruit is shelled (the black seed shows through the translucent flesh like a pupil/iris).
PART USED: Fruit
Nature- warm, neutral    FLAVOR: Sweet. Pleasant    CHANNEL: Heart, Spleen
FUNCTIONS
GROUP: Nourishing Blood
1. Invigorate the Heart and Spleen.[2,3] Tonifies the Spleen.[1,4] Cultivates the Heart.[1] Heart tonic.[4] Energy tonic.[4]
2. Calm the mind. Calm the Spirits. Supplements the intellect.[1]
INDICATIONS
1. Deficiency of Vital energy and Blood manifested as palpitation, insomnia, amnesia and dizziness, or during convalescence and after childbirth.[2,3]  Forgetfulness, nervousness and fatigue. Anemia.[1] Hyperactive mental activity, forgetfulness.[1]
2. Excessive menstrual flow.
3. Insomnia.[4]
CONTRAINDICATIONS: Internal  Phlegm-Fire, abdominal swelling and obstructions.
- Deficiency of Spleen Qi and Heart Blood: Tonifies the Qi and Blood, strengthens the Spleen, nourishes the Heart and calms the Shen Ginseng & Longan- Gui pi wan.
PREPARATIONS: Decoction  6-5 g; up to 30-60 g.[3]  Boiled or steamed or immersed in wine.[2] Decoction 4-9 g.[1]
Fruit 3-9 g.[2] Longan jelly- Mix 500 g longans with 500 g sugar and steam them.[4]
  
- Dizziness and underweight- Steam 15 g longans with 30 g lean pork, 2 fresh ginger slices, and an adequate amount of rice wine. Eat once a day.[4]
- Dizziness and edema after childbirth- Take 1 spoonful longan jelly with warm water.[4] Or boil 15 g longans with 5 red dates, 30 g brown sugar, and 6 g fresh ginger. Drink it as soup once a day.[4]

References
Inner Path can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.
Research

Longan (Dimocarpus longan Lour.) inhibits lipopolysaccharide-stimulated nitric oxide production in macrophages by suppressing NF-κB and AP-1 signaling pathways.
Kunworarath N, Rangkadilok N, Suriyo T, Thiantanawat A, Satayavivad J.
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE:
Flower, seed, and fruit of longan (Dimocarpus longan Lour.) have been used in the Traditional Chinese Medicine (TCM) serving as a common herb in relief of swelling which can be applied in cases of inflammatory diseases. However, the scientific evidence related to their effects on inflammation especially the possible cellular and molecular mechanisms of longan need to be clarified.
AIM OF THE STUDY:
To evaluate the anti-inflammatory effect of the various parts of longan including flower, seed, and pulp. The mechanisms and molecular targets involved in their effects were also investigated.
MATERIALS AND METHODS:
Different longan extracts were analyzed for their bioactive compounds and evaluated for anti-inflammation. Corilagin, ellagic acid, and gallic acid were detected using HPLC-DAD. In vitro anti-inflammatory effect of longan extracts and their polysaccharides were examined by analyzing nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Expression of the proteins that involved in NO production was detected by Western blot.
RESULTS:
Flower extract contained the highest amounts of total phenolics, total flavonoids, proanthocyanidins, corilagin and ellagic acid when compared to seed and pulp extracts. The extracts of different longan parts inhibited LPS-induced NO production with different potency. The highest potency for the inhibition of NO production was shown with flower extract follow by seed and pulp (IC50=128.2, 1127.4, and 1260.2μgmL(-1), respectively). The mechanisms of this anti-NO production were associated with their NO scavenging effect and their decreasing the expression and catalytic activity of an inducible nitric oxide synthase (iNOS). Moreover, these longan extracts suppressed LPS-induced degradation of IκBα and activation of NF-κB, activator protein-1 (AP-1), Akt, and mitogen activated protein kinases (MAPKs).
CONCLUSION:
These results suggest that the longan extracts possess anti-inflammatory property. Therefore, longan could provide potential dietary supplement for the treatment of inflammatory-related diseases.
PMID: 26721218 DOI: 10.1016/j.jep.2015.12.044 J Ethnopharmacol. 2016 Feb 17;179:156-61. doi: 10.1016/j.jep.2015.12.044. Epub 2015 Dec 22. ncbi.nlm.nih.gov

Longan (Dimocarpus longan Lour.) Fruit Extract Stimulates Osteoblast Differentiation via Erk1/2-Dependent RUNX2 Activation.
Park S, Kim JH, Son Y, Goh SH, Oh S.
Abstract
Longan (Dimocarpus longan Lour.) has been used as a traditional oriental medicine and possesses a number of physiological activities. In this study, we used cell-based herbal extract screening to identify longan fruit extract (LFE) as an activator of osteoblast differentiation. LFE up-regulated alkaline phosphatase (ALP) activity, induced mineralization, and activated Runx2 gene expression in MC3T3-E1 cells. Furthermore, treatment of MC3T3-E1 cells with LFE promoted the phosphorylation of extracellular signal-regulated kinase1/2 (Erk1/2); however, abrogation of Erk1/2 activation with PD98059 resulted in down-regulation of the phospho- SMAD1/5/8 and Runx2 levels, which in turn reduced the ALP activity. Our findings suggest that LFE exerts its osteogenic activity through activation of the ERK signaling pathway and may have potential as an herbal therapeutic or a preventive agent for the treatment of osteoporosis.
PMID: 26975768 DOI: 10.4014/jmb.1601.01092
J Microbiol Biotechnol. 2016 Jun 28;26(6):1063-6. doi: 10.4014/jmb.1601.01092. ncbi.nlm.nih.gov

In vitro antifungal activities of longan (Dimocarpus longan Lour.) seed extract.
Rangkadilok N1, Tongchusak S, Boonhok R, Chaiyaroj SC, Junyaprasert VB, Buajeeb W, Akanimanee J, Raksasuk T, Suddhasthira T, Satayavivad J.
Author information
Abstract
Longan, Dimocarpus longan Lour., contains polyphenolic compounds which exhibit several pharmacological properties. This study aims to evaluate antifungal activities of longan fruit extract in comparison to its active compounds. The results showed that longan seed exhibited antifungal activity against the opportunistic yeasts (Candida species and Cryptococcus neoformans). In contrast, longan pulp and whole fruit did not demonstrate any inhibitory effects. Ellagic acid showed the most potent antifungal activity followed by corilagin and gallic acid, respectively. Ellagic acid inhibited Candida parapsilosis and C. neoformans more effectively than Candida krusei and also some Candida albicans clinical strains. Baidam cultivar possessed higher antifungal activity (MIC=500-4000 μg/ml) as it contained higher contents of ellagic acid and gallic acid than Edor (MIC=1000-8000 μg/ml). For antibacterial activity, only corilagin and gallic acid possessed weak to moderate inhibitory effects against Staphylococcus aureus and Streptococcus mutans, respectively. Longan seed was then applied in the oral care products. Longan effervescent granule (5% extract) significantly reduced adhesion of C. albicans to acrylic strips. Mouthwash containing 0.5% extract exhibited good antifungal activity compared to a commercial product. These findings indicated that longan seed extract and its polyphenolic compounds can be used as an antifungal agent in oral care products for the treatment of opportunistic yeast infection.
PMID: 22245574 DOI: 10.1016/j.fitote.2011.12.023 Fitoterapia. 2012 Apr;83(3):545-53. doi: 10.1016/j.fitote.2011.12.023. Epub 2012 Jan 8. ncbi.nlm.nih.gov

Evaluation of xanthine oxidase inhibitory potential and In vivo hypouricemic activity of Dimocarpus longan lour. extracts
Shi-Yuan Sheu, Yuan-Tsung Fu, Wen-Dar Huang, Yung-Ann Chen, Yi-Chih Lei, Chun-Hsu Yao, Feng-Lin Hsu, Tzong-Fu Kuo
Abstract
Background: Longan is a fruit tree known to contain many phenolic components, which are capable of protecting people from oxidative damage through an anti-inflammatory mechanism. It may be also worthwhile to study the effect on lowering uric acid activity. Materials and Methods: This study investigates the lowering of uric acid using longan extracts, including flowers, pericarps, seeds, leaves, and twigs, on potassium-oxonate-induced hyperuricemia mice and its inhibitory actions against xanthine oxidase (XO) activities. Results: The findings revealed that ethyl acetate fraction of longan extracts exhibited strong XO-inhibitory activity, and the flower extracts (IC50 = 115.8 μg/mL) revealed more potent XO-inhibitory activity to those of pericarps (118.9 μg/mL), twigs (125.3 μg/mL), seeds (262.5 μg/mL), and leaves (331.1 μg/mL) in vitro. In addition, different dosages of longan extract (50–100 mg/kg) were administered to hyperuricemic mice. The lowering effect of longan extracts on uric acid at 75 mg/kg markedly reduced plasma uric acid levels in decreasing order: Flowers (80%) > seeds (72%) > pericarps (64%) > twigs (59%) > leaves (41%), compared with allopurinol (89%). Finally, 10 isolated phytochemicals from longan flowers were then examined in vitro. The results indicated that proanthocyanidin A2 and acetonylgeraniin A significantly inhibited XO activity in vitro. This is the first report providing new insights into the urate-reducing effect of phenolic dimer and hydrolyzable tannin, which can be developed to potential hypouricemic agents.
SUMMARY
Longan flower extracts possess more potent XO-.inhibitory activity than pericarps, twigs, seeds, and leaves in vitro
The lowering effect of longan flowers and seeds extracts markedly reduced plasma uric acid levels as compared to allopurinol in vivo
The extract proanthocyanidin A2 and acetonylgeraniin A were demonstrated potent XO inhibitory activity in vitro.
Pharmacognosy Magazine
Year : 2016 | Volume : 12 | Issue : 46 | Page : 206-212 DOI: 10.4103/0973-1296.182176 phcog.com