Kinetics of the aromatic L-amino acid oxidase from dead bovine spermatozoa and the effect of catalase on fertility of diluted bovine semen stored at 5 degrees C and ambient temperatures

Abstract

At limiting velocity 50 x 10(6) dead spermatozoa consumed 13.6 microliters O2/h and degraded 6.1 x 10(-7) mol L-phenylalanine/h. Substrate concentration in egg yolk was equivalent to 6.1 x 10(-3) M-L-phenylalanine. At a substrate concentration of 3 x 10(-2) M-L-phenylalanine, oxidase activity was significantly affected by oxygen tension (r = 0.947, P less than 0.01) and temperature (r = 0.995, P less than 0.01). Non-return rates were not affected when semen was stored at 5 degrees C in 20% egg yolk diluents with catalase but were significantly increased with semen stored at ambient temperatures of 15-23 degrees C.