"Ethnopharmacological" use of roots of Boerhaavia diffusa (B. diffusa) in the treatment of
epilepsy in Nigerian
folk medicine and reports showing the presence of a
calcium channel antagonistic compound "
liriodendrin" in its roots, led us to undertake the present study. The study was designed to investigate the methanolic root extract of B. diffusa and its different fractions including
liriodendrin-rich fraction for exploring the possible role of
liriodendrin in its anti-
convulsant activity. Air-dried roots of B. diffusa were extracted with
methanol by cold maceration. The
methanol soluble fraction of extract thus obtained was successively extracted to obtain
liriodendrin-rich fraction and two side fractions, that is,
chloroform fraction and phenolic compound fraction. Anti-
convulsant activity of methanolic extract (1000, 1500 and 2000 mg kg(-1), intraperitoneally (i.p.)) and its different fractions, that is,
liriodendrin-rich fraction (10, 20 and 40 mg kg(-1), i.p.,
chloroform fraction (20 mg kg(-1), i.p.) and phenolic compound fraction (1 mg kg(-1), i.p.) were studied in
pentylenetetrazol (PTZ)-induced
seizures (75 mg kg(-1), i.p.). The crude methanolic extract of B. diffusa and only its
liriodendrin-rich fraction showed a dose-dependent protection against PTZ-induced convulsions. The
liriodendrin-rich fraction also showed significant protection against
seizures induced by
BAY k-8644. These findings reiterated the anti-
convulsant activity of methanolic extract of B. diffusa roots. Furthermore, it can be concluded that the observed anti-
convulsant activity was due to its
calcium channel antagonistic action as this activity was retained only in the liodendrin-rich fraction, which has additionally been confirmed by significant anti-
convulsant activity of
liriodendrin-rich fraction in
BAY k-8644-induced
seizures.