The putative isolates of primary screening when subjected to secondary screening, showed different activity from that of primary screening; some of the active isolates didn’t show the activity in the secondary screening while some showed little activity and some showed improved activity. According to Bushell (1997), during the screening of the novel secondary metabolite, Actinomycetes isolates are often encountered which show antibiotic activity on agar but not in liquid culture. The result of primary and secondary screening revels that most of the active isolates were active against gram positive bacteria (S. aureus) than gram negative bacteria (E. coli and P. aeruginosa). The reason for different sensitivity between gram positive and gram negative bacteria could be explain to the morphological differences between these microorganisms, gram negative bacteria having an outer polysaccharide membrane carrying the structural lipopolysaccharide components. This makes the cell wall impermeable to lipophilic solutes, The gram positive should more susceptible having only an outer peptidoglycan layer which is not an effective permeability barrier