Objective: To determine the total phenolic content and in vitro xanthine oxidase inhibitory activity of methanol extracts of leaves and stem bark of Erythrina indica. Methods: Folin-ciocalteu method was used to determine the total phenolic content. Xanthine oxidase inhibitory activity was assayed spectrophotometrically and the degree of enzyme inhibition was determined by measuring the increase in absorbance at 295nm associated with uric acid formation. Results:The methanol extract of stem bark of E. indica contains higher level of total phenolic content (412.8 mg GAE/g extract) and also exhibited higher xanthine oxidase inhibition activity (IC50 52.75μg/mL) than the leaves. Conclusions: It could be concluded that the stem bark of E. indica was highly effective in xanthine oxidase inhibition and might be used for the gout related disorders.

Objective: To compare the inhibitory effects of acetone extracts from the stem bark of three Acacia species (Acacia dealbata, Acacia ferruginea and Acacia leucophloea) on nitric oxide production. Methods: The lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells were used to investigate the regulatory effect of acetone extracts of three Acacia stem barks on nitric oxide production and the expression of inducible nitric oxide synthase, cyclooxygenase-2 and tumor necrosis factor-α. Further, the phenolic profile of acetone extracts from the Acacia barks was determined by liquid chromatography-mass spec-trometry/mass spectrometry analysis. Results: All the three extracts significantly decreased LPS-induced NO production as well as the expression of inducible nitric oxide synthase, cyclooxygenase-2 and tumor necrosis factor-α in a concentration dependent manner (25, 50 and 75 μg/mL). In the liquid chromatography-mass spectrometry/mass spectrometry analysis, acetone extract of Acacia ferruginea bark revealed the presence of 12 different phenolic components including quercetin, catechin, ellagic acid and rosmanol. However, Acacia dealbata and Acacia leucophloea barks each contained 6 different phenolic components. Conclusions: The acetone extracts of three Acacia species effectively inhibited the NO production in LPS-stimulated RAW 264.7 cells and the presence of different phenolic components in the bark extracts might be responsible for reducing the NO level in cells.

Objective To compare the inhibitory effects of acetone extracts from the stem bark of three Acacia species (Acacia dealbata, Acacia ferruginea and Acacia leucophloea) on nitric oxide production. Methods The lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells were used to investigate the regulatory effect of acetone extracts of three Acacia stem barks on nitric oxide production and the expression of inducible nitric oxide synthase, cyclooxygenase-2 and tumor necrosis factor-α. Further, the phenolic profile of acetone extracts from the Acacia barks was determined by liquid chromatography-mass spectrometry/mass spectrometry analysis. Results All the three extracts significantly decreased LPS-induced NO production as well as the expression of inducible nitric oxide synthase, cyclooxygenase-2 and tumor necrosis factor-α in a concentration dependent manner (25, 50 and 75 μg/mL). In the liquid chromatography-mass spectrometry/mass spectrometry analysis, acetone extract of Acacia ferruginea bark revealed the presence of 12 different phenolic components including quercetin, catechin, ellagic acid and rosmanol. However, Acacia dealbata and Acacia leucophloea barks each contained 6 different phenolic components. Conclusions The acetone extracts of three Acacia species effectively inhibited the NO production in LPS-stimulated RAW 264.7 cells and the presence of different phenolic components in the bark extracts might be responsible for reducing the NO level in cells.