Background: The bark of Erythrina variegata Linn.(Ev) is used in Thai traditional medicine for the treatment of many
diseases in Thailand and is an ingredient in the Mahanintangthong remedy (antipyretic) and Lomammapruek remedy (analgesic and anti-inflammatory).
Objective: To study anti-inflammatory activities of ethanolic extract of E. variegata in vitro.
Material and Method: Bark of E. variegata was extracted with 95% ethanol. In this study, Griess reagent was used to
measure the anti-inflammatory activity by inhibitory effects of extract on nitric oxide production activated by lipopolysaccharide in RAW 264.7 cell lines, COX-2 and TNF-α were also tested by using ELISA techniques.
Results: The ethanolic extract of E. variegata showed potent anti-inflammation properties by inhibiting prostaglandins production through enzyme COX-2 and inhibitory activity against lipopolysaccharide induced nitric oxide production in RAW 264.7 cell lines with an IC50 value of 9.27+0.72 and 47.1+0.21 μg/ml, respectively. However it was not effective against TNF-α release.
Conclusion: The ethanolic extracts of E. variegata bark showed higher inhibitory effect on PGE2 as acute inflammation than inhibitory effect on Nitric oxide production and TNF-α release representing chronic inflammation. This study thus supports the use of E. variegata bark for treatment of inflammation-related diseases by Thai traditional medicine.

Keywords: Erythrina variegata, Anti-inflammatory activity, Nitric oxide, Tumor necrosis factor-alpha, Cyclooxygenase-2, PGE2