Identification of <i>Oreochromis niloticus</i> (Linnaeus, 1758) and <i>Tilapia zilli</i> (Gervais, 1848) using Isoelectric Focusing (IEF)

Abstract

Isoelectric focusing methodology using LKB 2117 Multiphor 11 electrofocusing apparatus was used for electofocusing and identification of Oreochromis niloticus and Tilapia zilli. The electrographs of the two species suggest clear protein differences producing species specific patterns. There were variations in the protein patterns at the cathode and the middle portions of the gels. The densitometric tracings of the low-resolution (pH 3-10) gels for the species also showed major differences in their banding patterns as shown by graphical representations of the bands. The banding patterns of O. niloticus and T. zilli were closer at the basic (cathodal) and mid pH range than at the acidic zone. Some family resemblance was observed in protein zones of similar mobilities.


Key words: Isoelectric focusing, Oreochromis niloticus, Tilapia zilli, protein profiles,


Journal of Aquatic Sciences Vol.17(2) 2002: 125-127