PGPB-driven bioenrichment and metabolic modulation of Salicornia europaea under marine Aquaponic conditions.

Abstract

This study analyzed the secondary metabolite profile of Salicornia europaea inoculated with Brevibacterium casei EB3 and Pseudomonas oryzihabitans RL18 in aquaponic systems, exploring the metabolic mechanisms responsible for the observed shifts. Experiments were conducted in both microcosm and pilot-scale aquaponic setups to evaluate how these metabolic shifts vary across different system scales and their potential contributions to the observed increased accumulation of bioactive compounds with antioxidant and antimicrobial properties, including some phenolic acids, such as caffeic acid (154-fold), flavonoids (2.85-fold), and some unsaturated fatty acids, such as oct-3-enoic acid (32-fold). Metabolic profiling revealed shifts in pathways associated with plant growth and stress resilience, such as amino acid and phenolic biosynthesis. Additionally, differences in metabolic responses observed between microcosm and pilot-scale systems underscored the importance of understanding scaling effects. These findings highlight the potential for optimizing aquaponic systems by leveraging microbial-plant interactions to enhance ecological and economic outcomes. This approach offers valuable applications in nutrient recycling, phytopharmaceutical development, and the advancement of saline agriculture within integrated aquaculture frameworks.