ABSTRACT
Secondary metabolism has long been classied as cellular metabolic activities that are not essential for bacteria growth, respiration, development, and reproduction. An enormous variety of bioactive molecules can be formed from the secondary metabolic pathways,1 many of which have ecological and environmental functions. ose bioactive chemical compounds, called secondary metabolites, can benet the producing organisms and improve their survival tness, by serving as bactericides or fungicides towards invading microorganisms, or by acting at specic receptors in competing organisms, as proposed by Williams et al. in 1989.2 Despite these observations, the exact purposes for the production of a large fraction of secondary metabolites in living organisms are not completely understood.3
