The study aimed to investigate the properties of plant extracts and bioactive substances from domestic plants, herbs, and marine algae. A bibliography was created to create an inventory table with 10-12 edible plants and algae with desired phytobiotic properties, followed by the collection/purchase of samples. Bioactive ingredients were recovered from selected plant and algal species using green extraction methods, including microwaves, ultrasounds, pressurized liquid extraction, and hydrodistilation.
The antibacterial activity of 9 bioactive extracts was tested in vitro against four different marine pathogens that affect aquaculture. Three extracts using eucalyptus and olive leaves were selected and tested for their dietary effects on sea bass using three different concentrations incorporated in the produced fishfeed. The fish developmental characteristics showed promising results for the dietary supplementation with the lowest concentration of olive leaf extracts, while the fillet composition and hematological analysis of experimental fish are ongoing.
A preliminary in vivo test was conducted on the disease resistance of fish infected by Aeromonas veronnii, showing promising results for the highest concentration of eucalyptus. An assessment of the health status of C. carpio and D. labrax specimens reared at Piscicola and Panittica farms was achieved, and no signs of infectious diseases were found. The most suitable healthy individuals were selected for experimental feeding procedures, with associated set-up of experimental tanks and chemical analysis of the water used during the tests.
Significant progress was made in developing, characterizing, and evaluating micro- and nanostructures for the controlled release of bioactive compounds. Advanced encapsulation techniques, including spray drying and electrospinning, were optimized to enhance the stability, bioavailability, and controlled release of key bioactive compounds. Various biopolymeric matrices, such as zein, modified starch, and maltodextrin, were evaluated for optimal performance. Zein-based encapsulation demonstrated the highest efficiency among the tested formulations, particularly for olive extract and garlic essential oil. Differential Scanning Calorimetry (DSC) assessments revealed that the encapsulation matrices effectively protected the bioactive compounds from thermal degradation.
Ongoing work focuses on scaling up the most promising encapsulation formulations, further refining bioactive loading efficiencies, and evaluating their performance in practical applications. The research outcomes contribute significantly to the project's scientific advancements in encapsulation technology, demonstrating that tailored micro- and nanostructured carriers can enhance bioactive stability, optimize controlled release, and improve integration into feed formulations.
