A modified agar disc diffusion method[31,32] was used
to determine the antimicrobial activity. Molten Mueller
Hinton agar No. 2 (HiMedia) was inoculated with
microbial cell suspension (100 毺L) and poured into
sterile Petri dishes. Sterile filter paper discs of 7 mm
diameter were impregnated with 20 毺L extract solution
equivalent to 500 毺g of the each dried extract in 100%
DMSO (Dimethylsulphoxide) and air dried. Thereafter
the discs were placed on the surface of the seeded agar
plates. Piperacillin (100 毺g/disc), Gentamicin (10 毺g/
disc) and Amphotericin B (100 units/disc) were used as
positive controls. Paper discs loaded with 20 毺L of DMSO
served as negative control. The plates were incubated
at 37 曟 for 24 h for all the bacterial strains while that
of fungal strains were incubated at 28 曟 for 48 h. The
experiment was done three times to minimize error. After
incubation period the antibacterial activity was evaluated
by measuring the inhibition zones. An inhibition zone
of 14 mm or greater (including diameter of the disc) was
considered as high antibacterial activity.