Many Bauhinia species are used extensively for traditional medicinal uses especially as anti-inflammatory
agents [1,2,3]. The present study aimed to the identification of triterpenoidal saponins
and polyphenols from the leaves of B. variegata. The n-butanol and ethyl acetate extracts of B. variegata leaves were separately fractionated on silica gel columns, followed by successive
chromatography on cellulose and sephadex LH-20 for final purification of the new 23-hydroxy-3α-[(O-α-L-1C4-rhamnopyranosyl-(1“→4')-O-α-L-4C1-arabinopyranosyl-oxy]olean12-en-28-oic acid O-α-L-1C4-rhamnopyranosyl-(1'''''→4'''')-O-β-D-4C1-glucopyranosyl-(1''''→6''')-O-β-D-4C1-glucopyranosyl ester (1) and eight known compounds, i.e. quercetin, 3,3'-dimethoxy-quercetin, 3,3',6-trimethoxy-quercetin,
isoquercitrin, quercetin 3-O-β-D-galacturonopyranoside, quercetin 3-O-β-D-neohespridoside [4], caffeic acid and ferulic acid, based on UV, HRESI-MS, 1D
and 2D NMR. Moreover, as a conclusion for the biological study on male Swiss Albino
mice (18–20g), it was found that the new saponin (1) is non-toxic (LD50 1000mg/kg b. wt.) and has a significant anti-inflammatory activity in comparison
with indomethacine. A significant anti-inflammatory effect was concluded from the
reduction recorded in granuloma diameter on treatment with 1 (19.2% and 20.9%) in comparison with indomethacin (32.1 and 35.5%) at 32 and 48 days
after ova injection, respectively, relative to control group. PGE2 level in granuloma
was also reduced after treatment with 1 (36.1 and 22.1%) with respect to that of indomethacine (44.4 and 32.4%) at 32 and
48 days after ova injection, respectively.
References: [1] Reddy, V. M. S., Yadava, R N. (2003). Nat Prod Res 17: 165. [2] El-Khatib, A.
S, Kaleel, A. E. (1995). Bull Fac Pharm (Cairo Univ) 64: 892. [3] Sosa, S. et al.
(2002). Phytomedicine 9: 646–53. [4] Agrawal, P. K. (1989). Studies in organic chemistry
39,13C NMR of flavonoids. Elsevier science, New York.
