A comparative study of esterase isozyme inhibition (classification of esterases) study in gill tissue of heteropneustes fossilis and channa punctatus

In the gill tissue of Heteropneustes fossilis and Channapuntatus, three distinct esterase zones were identified, exhibiting Rm values of 0.60 for Est-1, 0.40 for Est-2, and 0.30 for Est-3. The esterase zones Est-1 (0.60) and Est-2 (0.40) in Heteropneustes fossilis were classified as ER (Esterase resistant to inhibitors) esterases. In contrast, Est-3 (0.30) was only inhibited by paraoxon, while pCMB and eserine had no effect, leading to its classification as a CE (Carboxylic Esterase). The ESe esterase, defined as Est-1 (0.60), was uniquely inhibited by eserine, with no inhibition observed from paraxine or pCMB. Est-2 (0.40) showed no response to any of the three inhibitors, confirming its classification as an ER esterase. Only paraoxon and eserine were able to inhibit Est-3 (0.30), although it remained unaffected by other inhibitors.