Related Experiment Videos
The effect of ascorbate on proteolytic enzyme activities in fish
1Institute of Zoology, University of Innsbruck, Austria.
Summary
Ascorbic acid (vitamin C) can inhibit fish digestive enzymes like trypsin in lab settings. However, this effect is unlikely in live fish due to rapid vitamin C breakdown in their digestive systems.
Area of Science:
- Biochemistry
- Fish Physiology
- Nutritional Science
Background:
- Ascorbic acid (vitamin C) is essential for fish health.
- Understanding its interaction with digestive enzymes is crucial for aquaculture nutrition.
- Potential inhibition of proteases by ascorbic acid could impact nutrient absorption.
Purpose of the Study:
- To investigate the in vitro effect of ascorbic acid and its derivatives on fish digestive proteases.
- To assess the relevance of observed in vitro inhibition to in vivo conditions in fish.
Main Methods:
- In vitro enzymatic assays were performed using fish digestive extracts.
- Ascorbic acid, dehydroascorbic acid, and ascorbic sulfate were tested at a concentration of 15 mM.
- Trypsin and chymotrypsin activities were measured in three fish species.
Main Results:
- Ascorbic acid at 15 mM significantly inhibited trypsin activity by 50% in the studied fish species.
- Dehydroascorbic acid and ascorbic sulfate showed no inhibitory effect on trypsin or chymotrypsin.
- The rapid oxidation of ascorbic acid in the digestive tract suggests limited in vivo impact.
Conclusions:
- While ascorbic acid can inhibit fish trypsin in vitro, its relevance in vivo is minimal.
- The digestive environment rapidly converts ascorbic acid to less inhibitory forms.
- Further research should consider the in vivo stability and transformation of vitamin C in fish digestion.