title: Bioassay guided fractionation and identification of active anti-inflammatory constituent from Delonix elata flowers using RAW 264.7 cells.
abstract: BACKGROUND
  Delonix elata (L.) Gamble (Fabaceae) has been used in the Indian traditional medicine system to treat rheumatism and inflammation.
  
  
  OBJECTIVE
  To assess the anti-inflammatory effect of Delonix elata flowers and to isolate the active principle.
  
  
  METHODS
  The prompt anti-inflammatory constituent was isolated from Delonix elata flower extracts using bioassay guided fractionation in liposaccharide (LPS) stimulated RAW 264.7 macrophage cell line. The anti-inflammatory activity of extracts/fractions/sub-fractions/compounds (10, 25, and 50 µg/ml) was evaluated by estimating the levels of nitric oxide (NO), TNF-α, and IL-1β after 24 h of LPS induction (1 μg/ml). The isolated active compound was subjected to NMR, IR, and UV analyses for structure determination.
  
  
  RESULTS
  In an attempt to search for anti-inflammatory constituents, the active pure principle was isolated and crystallized as a white compound from Delonix elata flowers methanol extract. This active compound (50 µg/ml) decreased the release of inflammatory mediators levels such as NO (0.263 ± 0.03 µM), TNFα (160.20 ± 17.57 pg/ml), and IL-1β (285.79 ± 15.16 pg/ml) significantly (p < 0.05); when compared to the levels of NO (0.774 ± 0.08 µM), TNFα (501.71 ± 25.14 pg/ml), and IL-1β (712.68 ± 52.25 pg/ml) from LPS-stimulated macrophage cells. The active compound was confirmed as hesperidin with NMR, IR, and UV spectroscopy data. This is the first report of this compound from Delonix elata flowers.
  
  
  CONCLUSIONS
  The findings of the study support the traditional use of Delonix elata flowers to treat inflammation.
authors.affiliation: Division of Ethnopharmacology .
authors.forename: S
authors.initials: S
authors.lastname: Saravanan
authors.forename: V I
authors.initials: VI
authors.lastname: Hairul Islam
authors.forename: H A
authors.initials: HA
authors.lastname: David
authors.forename: R
authors.initials: R
authors.lastname: Lakshmi Sundaram
authors.forename: M
authors.initials: M
authors.lastname: Chellappandian
authors.forename: K
authors.initials: K
authors.lastname: Balakrishna
authors.forename: R
authors.initials: R
authors.lastname: Rajendran
authors.forename: P
authors.initials: P
authors.lastname: Vijayaraghavan
authors.forename: M
authors.initials: M
authors.lastname: Gabriel Paulraj
authors.forename: S
authors.initials: S
authors.lastname: Ignacimuthu
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000302:isolation & purification* / Q000494:pharmacology / Q000633:toxicity; D001681:Biological Assay; D002460:Cell Line; D005591:Chemical Fractionation; D004305:Dose-Response Relationship, Drug; D007887:Fabaceae / Q000737:chemistry*; D035264:Flowers / Q000737:chemistry; D006569:Hesperidin / Q000302:isolation & purification* / Q000494:pharmacology / Q000633:toxicity; D053583:Interleukin-1beta / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D053583:Interleukin-1beta; D010936:Plant Extracts; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D006569:Hesperidin
keywords: Hesperidin; Macrophages; inflammation; traditional plant