Evaluation of Anti-inflammatory and Anti-arthritis Activity of Isolated Fractions from Bauhinia purpurea Leaves Extracts in Rats

Bauhinia purpurea are used as antinociceptive, antidiarrhoeal, anti-inflammatory, anti-arthritis, analgesic, anticancer, antipyretic, anti-diabetics, anti-diarrheal activity etc. The flavonoids and polyphenol are present in Bauhinia purpurea and may play an important role in the treatment of inflammation and arthritis. Till date no one has documented about active constituents responsible for the anti-inflammatory and anti-arthritis activity. The present study was aimed to isolate fractions from Bauhinia purpurea leaves extracts, and assessed their anti-inflammatory and anti-arthritis activity in rats. The hydroalcoholic and aqueous extracts of Bauhinia purpurea leaves were prepared and tested for in vitro antioxidant activity namely DPPH, total polyphenol content, total flavonol content and reducing power assay. The antioxidant activity was performed only for proper selection of extracts, to isolate the polyphenol and flavonoids fractions from extract expressing maximum antioxidant activity. The different fractions were isolated from hydroalcoholic extracts by using column chromatography. The fractions FBP5, FBP8, FBP9 and FBP10 were further investigated for phytochemical screening to determine the nature of isolated compound. The fractions FBP8, FBP9 and FBP10 were screened for anti-inflammatory and anti-arthritis activity in carrageenan rat induced paw oedema, cotton pellet-induced granuloma model and adjuvant induced chronic arthritis in rats. The findings of in vitro antioxidant activity demonstrated that hydroalcoholic extracts expressed higher antioxidant activity compared to aqueous extract, and hence hydroalcoholic extracts was further selected for the isolation of various fractions. The results of phytochemical study imply that FBP8, FBP9 and FBP10 revealed the presence of polyphenol and flavonoids.  The fraction FBP8, FBP9 and FBP10 (25 mg/kg) exhibits significant anti-inflammatory and anti-arthritis activity. The FBP9 produces maximum anti-inflammatory and anti-arthritis activity compared to other fractions. These findings suggest that the anti-inflammatory and anti-arthritis activity of isolated fraction was due to presence of flavonoids and polyphenols.