Aquaculture has garnered significant attention due to its potential to address the increasing global demand for protein sources. It serves as a healthier and sustainable alternative to traditional proteins. It is the world’s fastest growing food production technology, increasing from 0.6 million metric tons in 1950 to 184.6 million metric tons in 2022. Nevertheless, there are challenges in ensuring animal growth performance, disease resistance, and overall health.
Probiotics, prebiotics and parabiotics have demonstrated significant physiological benefits when incorporated into the diets of aquatic animals. Functionalizing the diet with these additives presents a promising alternative to improve the productivity, sustainability and profitability of aquaculture. This is the objective of the Agroindustrial Processes research group at the University of La Sabana, which has optimized different unit operations to develop a food additive product that could be available to local farms. The methodology that allowed the design of the product was:
1. Bioactive selection: Screening of probiotic potential indigenous intestinal microorganisms isolated Tilapia from the departments of La Guajira and Los Llanos. This methodology integrated assays as Hemolytic Activity, Bile Salts and pH Survival, Antibiotic Minimal Inhibitory Concentration Determined by Etest Method and antibacterial pathogen activity.
2. Biomass production: Designing culture media utilizing agri-food by-products as sweet whey, palm kernel cake, molasses to reduce mass culture costs. The culture medium mixture design was carried out through the response surface method, taking into account variables such as final cell viability, change in survival at pH and bile salts and antibacterial activity against S. agalactiae.
3. Encapsulation of the bioactive: Implementation of drying technologies to increase viability and functionality of the microorganisms. Optimization of the drying technology included studying the optimal mixture of wall materials for feeding (maltodextrin, starch, sweet whey), the selection of equipment temperatures and air pressure.
4. Post-encapsulation: Increasing viability and functionality of the microorganism and extended shelf life of the product depending on the storage conditions. Physical and biological properties such as aW, humidity, hygroscopicity and cell viability have been measured over time.
5. In vivo and in vitro evaluation: Assessing the positive effects of the bioactive additive on fish productivity and well-being.
As the result of these capabilities, a probiotic consortium was developed including several bacterial genera such as Lactococcus, Priestia, Cetobacterium, Saccharomyces and others. High microbial growth of these strains was obtained in the formulated by-products culture media (> 1 x 108 CFU/mL, allowing large-scale biomass production and profitability.
Our results highlighted their significant in vitro antimicrobial activity against S. agalactiae and A. hydrophila, and immunomodulatory activity was also observed during in vivo trials.