Nyctanthes arbor-tristis Linn—A critical ethnopharmacological review

ETHNOPHARMACOLOGICAL RELEVANCE: Nyctanthes arbor-tristis (Oleaceae) is a mythological plant; has high medicinal values in Ayurveda. The popular medicinal use of this plant are anti-helminthic and anti-pyretic besides its use as a laxative, in rheumatism, skin ailments and as a sedative. Vitally, the natives plant it in their home gardens to pass on its medicinal usage to oncoming generations. AIM OF THE REVIEW: The present review encompasses an ethnopharmacological evaluation focusing on information on the chemical constituents, pharmacological actions and toxicology in order to reveal the therapeutic potential and gaps requiring research involvement. MATERIALS AND METHODS: The present review is based on searches in Scifinder®, Pubmed (National Library of Medicine) and books published on the subject during the period 1933 to 2012. RESULTS: Nyctanthes arbor-tristis is most important in local and traditional medicines especially in India for treating intermittent fevers, arthritis and obstinate sciatica. Crude extracts and isolated compounds from the plant were shown to be pharmacologically active against inflammation, malaria, viral infection, leishmanisis and as an immunostimulant. The major class of biologically active compounds are the iridoid glucosides incl., Arbortristoside A, B and C from the seeds active as anticancer, anti-leishmania, anti-inflammatory, anti-allergic, immunomodulatory and antiviral. Other molecules; calceolarioside A, 4-hydroxyhexahydrobenzofuran-7one and β-sitosterol from leaves have been reported to be active as anti-leishmanial, anticancer and anti-inflammatory, respectively. The crude extracts have been found to be safe with an LD₅₀ of 16gm/kg, while the LD₅₀ of arbortristoside-A isolated from the seeds was found to be 0.5g/kg. CONCLUSION: Mostly in-vitro or in some cases in-vivo models provide some evidence especially in the treatment of inflammatory conditions like arthritis, fevers related to malaria and protozoan diseases especially leishmaniasis. The only clinical study found, is for treating malaria, but with crude extract only. Further, more detailed safety data pertaining to the acute and sub-acute toxicity, cardio and immunotoxicity also needs to be generated for crude extracts or pure compounds.