Amylolytic activity in fish intestinal mucosa: temperature effects

Area of Science:

• Enzyme kinetics
• Fish physiology
• Comparative biochemistry

Background:

• Amylolytic enzymes in fish intestinal mucosa are crucial for carbohydrate digestion.
• Environmental temperature and feeding habits significantly influence enzyme activity.
• Understanding these factors is key to comprehending fish adaptation strategies.

Purpose of the Study:

• To investigate the activity, temperature characteristics, and activation energy of amylolytic enzymes in various fish species.
• To correlate enzyme properties with fish feeding habits and geographic origin (boreal vs. tropical/subtropical).
• To explore potential adaptations of these enzymes to environmental temperatures.

Main Methods:

• Studied amylolytic enzyme activity and kinetics in intestinal mucosa of nine fish species.
• Analyzed enzyme activity across different temperatures.
• Determined energy of activation using Arrhenius plots.
• Correlated enzyme properties with feeding habits and environmental temperature.

Main Results:

• Amylolytic activity was lower in predatory fish species.
• Enzyme activity at low temperatures correlated with natural environmental temperatures; boreal fish exhibited higher relative activity than tropical/subtropical species.
• A breakpoint in Arrhenius plots was observed in most species.
• Activation energy patterns differed between predators and benthophages, and varied with temperature regions.

Conclusions:

• Fish amylolytic enzyme properties are influenced by diet and habitat temperature.
• Observed variations in enzyme activity and activation energy suggest adaptation to specific environmental conditions.
• A reduction in activation energy at physiological temperatures may indicate thermal adaptation in fish enzymes.