Cultivation of Ulva sp. and Gracilaria sp. associated with a recirculating aquaculture system
摘要
Integrated multitrophic aquaculture (IMTA) has the potential to mitigate environmental impacts from fed aquaculture, by providing nutrient bioremediation while producing economically valuable seaweed biomass with biotechnological interest. Ulva sp. and Gracilaria sp. are species with recognised nutrient bioremediation potential, being promising candidates for association with recirculating aquaculture systems (RAS). Therefore, the performance of these species was evaluated in terms of growth rates, productivity, nutrient uptake rate and biochemical composition, when cultivated associated with Senegalese Sole (Solea senegalensis) aquaculture operating in RAS. Although both species showed the capacity to grow and uptake nutrients in this water, Ulva sp. presented higher growth (5.6 ± 1.1% day−1), and nutrient uptake (C = 93.7 ± 20.3 g m−2 week−1, N = 13.0 ± 2.86 g m−2 week−1) performance. Ulva sp. showed a higher content in chlorophyll a (2.51 ± 0.25 mg g−1 DW) and carotenoids (0.58 ± 0.08 mg g−1 DW), and a higher antioxidant capacity (ethanolic extracts), whereas Gracilaria sp. presented a higher protein content (25.8 ± 1.3% DW), and may be considered a rich source of phycobiliproteins (17.40 ± 2.08 mg g−1 DW). Thus, both species are valuable from a biotechnological perspective, having high potential for application in different industries.