PRODUCTION OF BACTERIOCINS BY LACTIC ACID BACTERIA USING AGROINDUSTRIAL BY-PRODUCTS AND ANALYSIS OF THE TECHNICAL-ECONOMIC FEASIBILITY OF THE PROCESS

Abstract

The advances observed in livestock activities highlighted the importance of the sector for food security, due to the capacity to produce healthy foods on a global scale, in a competitive and sustainable way. However, the intensive production system allows the outbreaks of infectious diseases caused by viruses, bacteria and parasites, which can generate serious losses for the sector worldwide. In this context, antibiotics have been used in animal production for the treatment and prevention of diseases or even to improve growth. Nonethless, the restriction of using these substances represents a major concern for the animal production industry and studies that are committed to the search for viable alternatives to this problem have gained increasing prominence. In this context, bacteriocins produced by lactic acid bacteria (LAB) have shown potential as an interesting alternative to replace some antibiotics in order to minimize the emergence of resistant bacteria. Studies on the production of probiotics and bacteriocins are generally performed in MRS medium (Man Rogosa and Sharpe), considered expensive for commercialization purposes. Therefore, the use of low-cost substrates, such as agro-industrial byproducts represents an alternative to make the production sustainable and economically viable. An example of a low-cost byproduct is sugarcane molasses, which has already been reported for the cultivation of lactic acid bacteria and the production of bacteriocin, since its composition mainly contains sugars fermentable by lactic acid bacteria (e.g. sucrose, glucose and fructose). Furthermore, due to the high costs attributed to complex nitrogen sources, new options that offer this nutrient must also be considered. Considering that, corn steep liquor (the main residue from the corn refining process) is a promising option to be used as a nitrogen source for the synthesis of biomolecules, due to its high protein and amino acid content.In this context, the main goals of this project is to study the production of bacteriocins by lactic acid bacteria, using sugarcane molasses and corn steep liquor as substrates in the cultivation medium. The kinetic and process data obtained, together with complementary data from the literature, will also be used to evaluate the technical-economic viability of the process, using the SuperPro Designer® software, thus aiming to simulate the influence of the process's operational conditions on costs. of production.