Different herbal preparations of Acalypha wilkesiana var. lace-acalypha (Muell & Arg.) are employed in traditional medicine for the
treatment and management of disease conditions such as wounds, tumors, hypertension, inflammations, skin infections, gastroenteritis and
many others. Ethyl 3,4,5-trihydroxybenzoate (ethyl gallate) and 1,2,3-benzenetriol (pyrogallol) had previously been isolated from the active
fractions of this plant. However, this present study was done to isolate compound(s) from one of the inactive fractions. Hence, a short
silica-gel column chromatography of the inactive fraction (5A) furnished a compound designated as 3 [Rf 0.15; [n]
20D 1.0300]. The
structure of 3 has been established to be D-arabino-hex-1-enitol-1,5-anhydro-2-deoxy (1,5-anhydro-2-deoxy-D-enopyranose-arabino-hex-1-
enitol) by a combination of 1H NMR, 13C NMR, MS and IR spectral techniques. Compound 3 recorded no antibacterial activity against B.
subtilis, S. aureus and Ps. aeriginosa. However, it demonstrated very weak antibacterial activities against E. coli and S. typhi. which were
slightly better than the activity furnished by 5A. Furthermore, it was observed that 3 was inactive against C. albicans. Surprisingly, the
crude extract and butanol fraction generally demonstrated comparably stronger antimicrobial activities than 3 implying that the purification
of the crude extract and 5A did not improve the activity demonstrated by 3.
Key words: A. wilkesiana var. lace- acalypha; inactive fraction; chromatography; antibacterial; 1,5-anhydro-2-deoxy-D-enopyranosearabino-hex-1-enitol.
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