This study was carried out used some natural antibacterial substances(_Pelargonium zonale_(Pz) and _Ocimium basilicum_(Ob) as leave extracts to improvement shelf-life and safety of minced beef. Experimental procedures included: comparative study of the different solvents, water, 70% aqueous acetone and hexane, the leave extracts were assessed against clinical bacterial, Gram-negative bacteria (_Escherichia coli _O157:H7, _Klebsiella pneumonia_,_Proteus vulgaris_ and _Serratia marcescens_) and ... إقراء المزيد