Impactos de diferentes partes da beterraba vermelha (Beta vulgaris L.) sobre o crescimento e atividade metabólica de probióticos e da microbiota colônica humana

• Ano de defesa: 2023
• Autor(a) principal: Oliveira, Sônia Paula Alexandrino de
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal da Paraíba; Brasil; Ciências da Nutrição; Programa de Pós-Graduação em Ciências da Nutrição; UFPB
• Palavras-chave em Português: Nutrição - Ciências; Beta vulgaris L; Microbiota intestinal; Ingrediente funcional; Propriedades prebióticas; Beta vulgaris L.; Intestinal microbiota; Functional ingredient; Prebiotic properties; CNPQ::CIENCIAS DA SAUDE::NUTRICAO
• Link de acesso: https://repositorio.ufpb.br/jspui/handle/123456789/29846

Dietary patterns that include regular consumption of prebiotic compounds are capable of modulating the composition and metabolism of the human intestinal microbiota, playing an important role in the health of the host. Red beet (Beta vulgaris L.) is an important vegetable species with a considerable supply of nutrients and bioactive compounds, especially dietary fiber, phenolic compounds and betalains. The aim of this study was to evaluate the prebiotic potential of freeze-dried products obtained from different parts of red beet by checking their effects on the growth and metabolism of probiotic strains (Lactobacillus acidophilus LA-05, Lacticaseibacillus casei L-26 and Limosilactobacillus fermentum 296) and the human colonic microbiota under in vitro conditions. The tests were carried out with freeze-dried parts of the root (FDBR) and stalk/leaf (FDBSL) of the red beet cultivar Early wonder. FDBR and FDBSL were analyzed to determine their nutritional composition and physicochemical parameters. Next, Lactobacillus strains were exposed to simulated conditions of the gastrointestinal tract in the presence of FDBR and FDBSL, when aspects related to cell viability and physiological functionality, total antioxidant capacity and total phenolic compounds were evaluated after the three main phases of digestion (mouth, stomach and intestine). In a second stage, new samples of FDBR and FDBSL were subjected to simulated gastrointestinal digestion and the digestion product was evaluated in fermentation trials using them as the sole carbon source for the cultivation of probiotic strains and to assess the modulation of the colonic microbiota using fecal inoculum. The prebiotic activity score was calculated and microbial metabolic activity was monitored by determining pH and the content of sugars and organic acids in the different cultivation systems. The phenolic profile and total antioxidant capacity were also monitored during the simulated digestion and fermentation phases with fecal inoculum. FDBR and FDBSL showed high levels of soluble (5.25 and 11.10 g/100 g) and insoluble fiber (21.43 and 37.03 g/100 g), pectins (8.45 and 9.51 g/100 g), betalains (3.36-28.99 g/100 g) and a variety of phenolic compounds. FDBR and FDBSL stimulated the growth of the probiotic strains tested with high viable cell counts (>9 log CFU/mL), increased production of acetic, butyric, lactic and propionic acids and caused changes in the levels of phenolic compounds during 72 h of cultivation. They also showed positive prebiotic index values (≥0.17) for the different ceas tested. During exposure to simulated digestion, FDBR and FDBSL increased the survival and maintenance of active physiological functions in the probiotic strains, as indicated by the high viable cell count (≥3.5 logs CFU/mL) and percentage of physiologically active cells (>25.2% for FDBR and 23.1% for FDBSL). FDBR and FDBSL increased the abundance of Lactobacillus spp./Enterococcus spp. (3.64-7.60%) and Bifidobacterium spp. (2.76-5.78%) and decreased the abundance of Bacteroides spp./Prevotella spp. (9.56-4.18%), Clostridium histolyticum (1.62-1.15%) and Eubacterium rectale/Clostridium coccoides (2.33-1.49%) during 48 h of colonic fermentation, resulting in positive prebiotic indices (> 3.61). FDBR and FDBSL promoted intense metabolic activity, evidenced by a decrease in pH, an increase in the production of lactic, acetic, butyric and propionic acid, and the consumption of glucose and fructose over time in the probiotic culture and in the in vitro colonic fermentation assays. Changes in the content of phenolic compounds and high antioxidant capacity during colonic fermentation were also observed. FBRD and FDBSL showed potential prebiotic properties, contributing to the beneficial modulation of the composition and metabolic activity of the human intestinal microbiota, and could be exploited in the formulation of functional food products and dietary supplements.