Nutrient-efficient catfish-based aquaponics for producing lamb's lettuce at two light intensities

Area of Science:

• Aquaculture and Hydroponics
• Plant Physiology
• Food Science

Background:

• Aquaponics systems integrate aquaculture and hydroponics for sustainable food production.
• A nutrient-efficient catfish (Clarias gariepinus)-based aquaponics system was utilized.
• Two leafy vegetables, lamb's lettuce (Valerianella locusta) and arugula (Eruca sativa), were cultivated.

Purpose of the Study:

• To assess the impact of varying light intensities on the growth and phytochemical content of two lamb's lettuce and two arugula cultivars.
• To evaluate the health status, morphological characteristics, and antioxidant properties of the plants.
• To determine the cytotoxicity of leaf extracts on Caco-2 intestinal cells.

Main Methods:

• A 4x2 factorial design was employed with two light intensities (120 and 400 μmol m⁻² s⁻¹).
• Morphological parameters (root length, plant height, leaf number, etc.) were measured.
• Phytochemical analysis included total phenolic content, antioxidant capacity, and Caco-2 cell cytotoxicity assays.

Main Results:

• Lamb's lettuce cultivars exhibited high greenness and health, with var. de Hollande showing superior morphology.
• Arugula cultivars, particularly E. vesicaria var. sativa, displayed lower health and greenness under high light.
• Higher light intensity increased antioxidant and polyphenol content, correlating with enhanced Caco-2 cell viability.

Conclusions:

• Successful industrial aquaponics requires optimized, species-specific acclimatization conditions.
• Cultivar-specific responses to environmental factors are crucial for aquaponics efficiency.
• Light intensity significantly influences the phytochemical profile and potential health benefits of aquaponically grown vegetables.