Figure 6. Specific activity of gulonolactone oxidase (Gulo; µg ascorbic acid formed h−1 g−1) from the kidney of Himantura signifer kept in freshwater (FW) on day 0 (control), or exposed to brackish water (salinity 20) for 1 or 6 days after a 4-day progressive increase in salinity.
Results represent mean ± S. E. M. (N = 4). Means not sharing the same letter are significantly different (P<0.05).