In two recent phytochemical studies [1,2], the flavonoides of Pongamia pinnata fruits were studied. Because of the broad structural and biological variation of Pongamia extracts [3–6], our study aimed at the isolation of flavonoids in the 70% aqueous
methanol extract (AME) of Pongamia pinnata leaves and evaluation of its hypoglycaemic, anti-inflammatory, hepatoprotective and
antioxidant activities. Successive column chromatographic separation has led to isolation
of two new isoflavonoids, genistein 4'-O-methyl ether 7-O-β-D-rutinoside and 2',5'-dimethoxy-genistein 7-O-β-D-apiofuranosyl-(1'''→6“)-O-β-D-glucopyranoside and a new rotenoid, 12a-hydroxy-α-toxicarol, together with seven
metabolites, vicenin-2, kaempferol 3-O-β-D-rutinoside, rutin, vitexin, isoquercitrin, kaempferol 3-O-β-D-glucopyranoside, 11,12a-dihydroxy-munduserone, kaempferol, and quercetin. The
structures were established by UV, ESI-MS, 1D and 2D NMR [1–3,5,7]. As a conclusion
for the biological studies on male Swiss Albino mice (18–20g) infected with Egyptian
Schistosoma mansoni 100±10 cercariae/mouse [8] and rats (100–150g), it was found that the AME is non-toxic to mice (LD50 up to 4g.Kg-1 b.wt, the maximum soluble dose). At the two dose levels (100 and 200mg Kg-1 b. wt.), it improved significantly the liver functions i.e reduced the elevated ALT
and GGT serum levels in comparison with praziquantel and reduced the MDA and GSH levels
in liver homogenate, in comparison with silymarin. Also, it showed significant hypoglycemic
and anti-inflammatory activities at the dose levels of 50 and 200mg Kg-1 b.wt, respectively. Moreover, a significant reduction of granuloma diameter and esenophilic
counts was recorded through a histopathological investigation on treatment with AME
(200mg Kg-1 b. wt.), in comparison with mofebutazone.
References: [1] Ahmed, G. et al. (2004). Phytochemistry 65: 921. [2] Yadav, P. P. et al. (2004).
Phytochemistry 65: 439. [3] Sekine, T. et al. (1999). Phytochemistry 52: 87. [4] Ito,
C. et al. (2004). Planta Med. 70: 585. [5] Laupattararakasem, P. et al. (2004). Planta
Med. 70: 496.. [6] Ito, C. et al. (2004). J Ethnopharmacol. 105: 39. [7] Agrawal,
P. K. (1989) Studies in organic chemistry 39,13C NMR of flavonoids. Elsevier science, New York, pp. 283–364. [8] Liang, Y.S. et al.
(1987) Proceeding of the first Sino-American Symposium, 1: 34.