Alltheextractsandessentialoilsweredissolvedin10%(v/v)
dimethylsulphoxideinwatertoobtaintheworkingconcentrationof
100mg/mL.Twentymicroliters(20 μL) ofthetestsolutionwas
asepticallyloadedontosteriledisks(6mmdia.Whatmans, England)
and thenair-dried.Negativecontroldisksweresimilarlyprepared
with10%dimethylsulphoxideandthenairdried.Onceprepared,the
diskswerestoredovernightinsterilePetri-dishesuntiltheirapplica-
tion thefollowingdayindiskdiffusion assays.Standardantibiotic
diskswereusedaspositivecontrolsforeachorganism.