Enhancing nutraceutical functionality through the integration of sea buckthorn bioactive compounds and a psychobiotic strain in an oat-based cereal bar

Mental health disorders affect almost one in eight individuals worldwide, underscoring the need for accessible, nutrition-based approaches capable of influencing the gut–brain axis. Psychobiotics have gained increasing attention for their ability to affect microbial and neurochemical pathways, and in parallel, sea buckthorn (SB) is recognized as a rich source of polyphenols with strong antioxidant potential. This study investigated the synergistic integration of Lactiplantibacillus plantarum 299 V with SB (fresh or freeze-dried) in oat-based cereal bars to enhance bioactive stability and support the development of a stable delivery system. A lipid-rich chocolate coating was applied to improve the protection and retention of bioactive compounds during storage. SB incorporation enhanced antioxidant activity, with the freeze-dried coated formulation maintaining 70% of its initial DPPH radical scavenging activity (3.68 to 2.58 mmol TE/g DW) and 87% of ABTS activity (12.71 to 11.04 mmol TE/g DW) after 70 days. Sensory assessment confirmed good consumer acceptability for the optimized formulation. Overall, these findings indicate that oat-based cereal bars are promising carriers of the psychobiotic strain L. plantarum 299 V and SB bioactive compounds.