The commenced research was proposed to produce known active/novel metabolites by microbial biotransformation by an easy and economic way and also to develop microbial models for CYP enzymes for drug metabolism studies. This study was also aimed at anticipation of the nature of enzyme involved in fungal biotransformation and affinity of the fungal enzyme towards substrate. It observed from this study that, Cunnighamella elegans, Cunnighmella echinulata and Aspergillus Niger have shown the ability to convert Loratadine to its metabolites due to the presence of enzymes essential for biotransfromation of Loratadine. Thus, the present study revealed that, Cunnighamella elegans can be used as model for CYP2D6 and Aspergillus niger can be used as model for CYP3A4 to study pharmacological and toxicological properties and the biotransformation of other similar drugs. Enzyme kinetic studies revealed that, metabolism mediated by enzymes present in Cunnighmella echinulata possessed low Km value than enzymes present in Cunnighamella elegans and Aspergillus niger. So the enzyme present in Cunnighamella echinulata has more affinity towards Loratadine when compared with other two enzymes present in Cunnighamella elegans and Aspergillus niger. So,maximum metabolite can be produced by Cunnighmella echinulata with less quantity of Loratadine.