An extract of henna (Lawsonia inermia) was found to be active in vitroagainst gram
(+) and gram (-) bacteria including Bacillus anthracis, B.cereus, B. subtilis,
Enterobacter aerugenes,Escherichia coli 0128-B7, E.coli 055-B5, E. coliO127-B8,
Proteus mirabilis, P. vulgaris, Pseudomonas aeruginosa Salmonella typhosa,
S.paratyphi, Sarcina sp. Shigella dysenteriae type 1, S. dysenteriae type 7, S.
dysenteriae type 9, Staphylococcus aureus hemolyticus, S. citreus and S.
epidermidis Exposed lesions on rabbits, guinea pigs and mice caused by
subcutaneous inoculation of a beta hemolytic, coagulase positive strain of
Staphylococcus aureus were healed within 8 days after exposure to a lyophilized
extract of henna. The antimicrobial activity of the extract may be due to Lawsone,
the dying principle of henna