Total antioxidant capacity of fish seminal plasma

•Total antioxidant capacity was measured for the first time.•13 species have been characterized.•Most of TAC in seminal plasma is related to low molecular weight antioxidants.

Total antioxidant capacity (TAC) was measured in the seminal plasma of 13 fish species using a commercial assay kit. TAC values are quite variable among the 13 species studied, from 0.008 mM of Trolox for rainbow trout to 1.909 mM of Trolox for Eurasian perch. Two species of percid fish were distinguished by high values of TAC. Most of TAC was attributed to fraction ≤ 2 kDa which suggests that TAC in seminal plasma is related to low molecular weight antioxidants. The assay kit was not useful for measurements of TAC in fish blood plasma.