Superoxide dismutase activities during the molting cycle of mud crab

Abstract

The observation focuses on superoxide dismutase activities in mud crabs throughout the 12 stages (normal stage, three stages of premolt, and eight stages of postmolt) of the molting cycle. The results showed that superoxide dismutase activities in the hepatopancreas, gill, integument and haemolymp ranged from 5.25 ± 1.46 to 52.56 ± 17.05, 8.67 ± 1.33 to 29.52 ± 9.53, 2.48 ± 0.49 to 14.14 ± 7.25, and 0.53 ± 0.16 to 1.20 ± 0.37 units per mg protein-1, respectively. The highest activities were observed in the hepatopancreas and integument during intermolt, while the activities in the haemolymph and gill were at the highest level at 6 and 24 hours postmolt, respectively. Superoxide dismutase is responsible for the eradication of superoxide anions released from metabolic processes and respiratory burst. This research demonstrated the relationship between the enzyme activities affecting metabolism, and the immune system of mud crabs throughout the 12 stages of the molting cycle.