Most Tahera Naznin, Jessica Nolan
The utilization of aquaculture wastewater for crop production represents a key component of the circular bioeconomy, promoting efficient nutrient recycling and sustainable food production. Aquaculture effluent contains substantial amounts of dissolved nutrients derived from fish metabolism and uneaten feed, which can serve as valuable nutrient sources for plant growth. This study evaluated the growth performance, photosynthetic pigments, and antioxidant properties of leaf lettuce cultivated using wastewater generated from blue tilapia culture systems. Four nutrient-source treatments were investigated: a commercial nutrient solution (control), conventional fishmeal-based feed (FM), feed in which 50% of the FM was replaced with black soldier fly larvae meal (BSFL), and feed in which 50% of the FM was replaced with mealworm larvae meal (MW). The results demonstrated that wastewater derived from the MW treatment significantly enhanced lettuce growth and quality attributes compared with the other treatments. Lettuce plants grown with MW-derived wastewater exhibited increased biomass accumulation, higher chlorophyll and carotenoid concentrations, and enhanced antioxidant activity. Principal component analysis (PCA) further revealed a strong association between the MW treatment and growth-related parameters, including plant height, leaf area, biomass production, and chlorophyll content, whereas the BSFL treatment was more closely associated with carotenoid accumulation. The findings indicate that replacing 50% of conventional fishmeal with insect-derived protein sources, particularly mealworm larvae meal, can enhance both the productivity and nutritional quality of lettuce. This approach offers a promising strategy for advancing sustainable aquaculture–horticulture integration and supporting circular bioeconomy objectives.