Identification of Penicillium species was not easy and needed accurate and expertise mycologist. Three different species, namely; P.hordei (eight), P.roqueforti (eleven) and P.aurantiogresium (twenty nine) were subjected to polyphasic approach of four chemotaxonomical markers; volatile metabolite (VM), fatty acid (FA) and secondary metabolite (SM) profiles as well as the random amplified polymorphic DNA with the polymerase chain reaction (RAPD-PCR) fingerprinting pattern. The results revealed the succession of all the investigated markers using one growth medium (YES) to identify and...