Effectiveness of L-ascorbyl-2-polyphosphate as an ascorbic acid source for sea cucumber, Apostichopus japonicus

A feeding trial was conducted to determine the adequate dietary ascorbic acid (AsA) levels and the effects on growth, meat quality and antioxidant status of sea cucumber (10.04 +/- 0.06 g), Apostichopus japonicus. L-ascorbyl-2-polyphosphate (35% AsA equivalent) was supplemented separately to the basal diet to obtain five AsA levels, 0, 598, 1471, 4676 and 14140 mg kg(-1) diet respect. After 60-day feeding trial, the sea cucumbers fed diets containing 598 and 1473 mg AsA kg(-1) showed significantly higher (P < 0.05) body weight gain and specific growth rate values than the sea cucumbers led control diets. The sea cucumbers fed diets containing 1473 and 4676 mg AsA kg showed significantly higher (P < 0.05) hydroxyproline contents than those of the sea cucumbers fed diets containing 0 and 598 tug AsA kg(-1). Antioxidant, enzymes such as antioxidant capacity, superoxide dismutase and glutathione peroxidase showed increasing trends with the increasing dietary AsA levels, but no significant differences (P > 0.05) were observed when the sea cucumbers fed diets with high dietary AsA levels. The content of malondialdehyde had the opposite trend of antioxidant enzymes. In conclusion, the adequate dietary AsA level focusing on growth performance of sea cucumber is between 598 and 1473 mg kg(-1) diet. Furthermore, high level of dietary AsA (between 598 and 4676 rug kg(-1) diet) improved meat quality and antioxidant status.