Potencial de coprodutos de frutas tropicais como recursos circulares para promover a viabilidade probiótica de Lactobacillus em bioprocessamentos e a modulação da microbiota intestinal

Abstract

Fruits are widely known for their nutritional value and functional potential, and recently, fruit co-products have gained special attention due to their richness in bioactive compounds. These co-products are derived from the fruit processing industry, basically consisting of peels, seeds and stalks, and are generally discarded. This study aimed to evaluate the potential for using co-products from fruit processing, acerola (Malphigia glabra L., CACE), cashew (Anacardium occidentale L., CCAS) and guava (Psidium guayaba L., CGUA) as means for multiplication (fermentation) and maintenance of viability of Lactobacillus acidophilus LA-05 and Lacticaseibacillus paracasei L-10 during freeze-drying, storage and simulated gastrointestinal digestion, as well as the effects on the relative abundance of different intestinal bacterial groups. microbial metabolism and antioxidant capacity during 48 h of fecal fermentation using human fecal inoculum. The results showed that, when used as culture media, CACE, CCAS and CGUA resulted in viable Lactobacillus cell counts ≥8.8 log CFU/g after 24 h, in addition to the ability to reduce the lag phase. Throughout fermentation, there was a reduction in the concentration of glucose and fructose sugars, with a concomitant increase in the production of organic acids, and a reduction in pH (3.46-3.99). The fermentation of co-products by Lactobacillus promoted an increase in the concentration of phenolic compounds, which contributed to an increase in antioxidant activity at the end of the fermentation process. After the freeze-drying process of Lactobacillus strains in the fermented co-products, high survival rates (> 86%) were observed, demonstrating that these media could protect the strains during freeze-drying. At the end of storage, L. acidophilus LA-05 and L. paracasei L-10 lyophilized with CACE, CCAS and CGUA showed reductions (2-3 logarithmic cycles) p < 0.05 smaller than when lyophilized in the control medium. Furthermore, CACE, CCAS and CGUA were able to reduce the size of injured and dead subpopulations during the simulated digestion steps. Fruit coproduct media increased the relative abundance of beneficial bacterial groups while decreasing or maintaining the relative abundance of non-beneficial bacterial groups, indicating putatively selective stimulatory effects on beneficial intestinal bacterial populations. Concomitant to this, there was a stimulation of microbial activity, with a change in the metabolic profile, resulting in a decrease in pH, sugar consumption, production of short-chain fatty acids, an increase in phenolic compounds and antioxidant capacity during fecal fermentation. These results suggest that CACE, CCAS and CGUA can act as efficient culture media for the growth of L. acidophilus LA-05 and L. paracasei L-10, with a protective effect on these strains during freeze-drying. storage and exposure to simulated gastrointestinal digestion. Furthermore, they can induce beneficial changes in the relative abundance of various bacterial groups, as well as in the metabolic activity of the human intestinal microbiota, making them new and sustainable circular candidates for use as symbiotic ingredients.