Acalypha wilkesiana var. lace-acalypha (Muell & Arg.) is a cultivated ornamental plant used in folkloric medicine for the treatment of
fever, bacterial, skin fungal infections, wounds, tumors, inflammations and gastro-intestinal troubles. Silica gel column chromatography of
the butanol fraction gave two polyphenolic compounds, designated as compounds 1 [m.p. 148-150 0C; Rf 0.67; [n]
20D 1.4118 ] and 2 [m.p.
130-132 0C; Rf 0.46; [n]
20D 1.4079]. The structures of 1 and 2 have been established to be ethyl 3, 4, 5-trihydroxybenzoate (ethyl gallate)
and 1, 2, 3-benzenetriol (pyrogallol or fouramine brown) respectively using the 1H NMR, 13C NMR, MS and IR spectral techniques. Both
polyphenols were strongly bacteriostatic against against B. subtilis, S. aureus, E. coli, Ps. aeriginosa and S. typhi. Furthermore, 2 was more
suppressive of the bacterial strains than 1. However, neither gave any anticandidal activity. The crude extract and butanol fraction
demonstrated comparatively weaker antimicrobial activities than the two isolated compounds. The results of the antimicrobial screening
have lent scientific credence to the traditional uses of the plant.
Key words: Polyphenols; ethyl gallate; pyrogallol; bacteriostatic; A. wilkesiana var. lace-acalypha.
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