In addition to their use in human medicine, antimicrobials are also used in food animals and aquaculture, and their use can be categorized as therapeutic against bacterial infections. The use of antimicrobials in aquaculture may involve a broad environmental application that affects a wide variety of bacteria, promoting the spread of bacterial resistance genes. Probiotics and bacteriocins, antimicrobial peptides produced by some types of lactic acid bacteria (LAB), have been successfully tested in aquatic animals as alternatives to control bacterial infections. Supplementation might have beneficial impacts on the intestinal microbiota, immune response, development, and/or weight gain, without the issues associated with antibiotic use. Thus, probiotics and bacteriocins represent feasible alternatives to antibiotics. Here, we provide an update with respect to the relevance of aquaculture in the animal protein production sector, as well as the present and future challenges generated by outbreaks and antimicrobial resistance, while highlighting the potential role of probiotics and bacteriocins to address these challenges. In addition, we conducted data analysis using a simple linear regression model to determine whether a linear relationship exists between probiotic dose added to feed and three variables of interest selected, including specific growth rate, feed conversion ratio, and lysozyme activity.

Swine production is of great importance worldwide and has huge economic and commercial impact. Due to problems with bacterial infection, the use of antimicrobials has increased in the last decades, particularly in Latin America and Asia. This has led to concerns about antimicrobial resistance, which poses risks to human health and the environment. The use of probiotic organisms has been proposed as an alternative to this use, as these beneficial bacteria can produce antimicrobial peptides, such as bacteriocins, which allow the induction of inhibitory effects against pathogenic microorganisms. Among probiotics, some bacteria stand out with the inhibition of animal pathogens. The bacteriocin-like inhibitory substances (BLISs) of Lactococcus lactis subsp. lactis strain L2, present in its cell-free supernatant, were tested against pathogenic strains isolated from pig samples, such as Escherichia coli, Salmonella enterica, Streptococcus suis, Streptococcus dysgalactiae, Staphylococcus hyicus, and Enterococcus faecalis. Compounds secreted by L. lactis L2 have been shown to inhibit the growth of some pathogenic species, particularly Gram-positive bacteria, with S. suis being the most prominent. Antimicrobial peptides with a molecular size of 500–1160 Daltons were isolated from BLISs. The results highlight the potential of L. lactis BLISs and its peptides as natural antimicrobials for use in the food industry and to reduce the use of growth promoters in animal production.

The number of people with dietary restrictions on dairy products has increased significantly due to lactose intolerance/allergy or adoption of vegan diets. Organic acid-producing probiotics have been used in fermented beverages, such as those based on soy, with good results. Such molecules have in fact been described for their role in sensory analyses and benefits to human health. Therefore, this study suggested the evaluation of an alternative soy extract-based beverage that could act as a functional food. For this purpose, products and biomass concentrations were monitored throughout soy extract fermentation through acidification kinetics and cell count. The effect of inulin on the growth of the probiotic strains Bifidobacterium longum and Lactobacillus acidophilus in co-culture with Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was evaluated (technical replicates). It was observed that the addition of inulin reduced the time of fermentation by L. acidophilus, while no statistically significant effect was observed in the post-acidification period. In B. longum fermentation, the process did not change in the presence of inulin, but there was a significant increase in viability and survival in the post-acidification period. Therefore, it can be concluded that the strains studied can be used in the formulation of soy-based drinks and that inulin positively influenced the viability of both probiotics in fermented drinks tested.