Ethanolic crude extracts from the roots of
Chaptalia nutans
, traditionally used in Brazilian folk medicine, were screened against
Staphylococcus aureus
,
Escherichia coli
, and
Pseudomonas aeruginosa
by using the disk diffusion test technique.
S. aureus
with 14 mm inhibition zone was considered susceptible.
E. coli
and
P. aeruginosa
without such a zone were considered resistant. As a result of this finding,
the ethanolic crude extract was fractionated on silica gel column chromatography
into five fractions. The ethyl acetate fraction was active against
S. aureus
and
Bacillus subtilis
. Further column chromatography separation of the ethyl acetate fraction afforded
30 fractions, which were assayed against
S. aureus
. Fractions 16 and 17 showed inhibition zones with
S. aureus
, indicating the presence of active compounds, and were subjected to purification
by repeated preparative thin layer chromatography. The pure compound 7-O-
β
-D-glucopyranosyl-nutanocoumarin inhibited
B. subtilis
and
S. aureus
at concentrations of 62.5
µ
g/ml and 125
µ
g/ml, respectively. The antibacterial property of
C. nutans
appears to have justified its use for the treatment of wounds, which are contaminated
through bacterial infections.
