Effect of probiotic supplementation on plasma metabolite profile after Roux-Y gastric bypass: a prospective, randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND/OBJECTIVE: There is evidence that metabolic profile changes after Roux-Y gastric bypass (RYGB), especially due to modifications in the gastrointestinal tract. In addition, previous studies have suggested that probiotics can modify the microbiome and produce metabolites important for metabolic health maintenance. In this sense, the aim of this study was to verify the influence of probiotic supplementation on the plasma metabolite profile after RYGB. METHODS: This was a randomized, double-blind, placebo-controlled clinical trial conducted with 31 patients subjected to RYGB surgery, randomized in probiotic group that was supplemented with a probiotic supplement (FloraVantage®) for 3 months after surgery or a placebo group. Plasma metabonomics was performed using nuclear magnetic resonance (NMR) at the preoperative period (T0) and at 45-50 days (T1) and 90-95 days (T2) during the postoperative period/intervention. RESULTS: Reductions in trimethylamine-N-oxide (TMAO) and alanine were observed in both groups, however this reduction was greater in the probiotic group (TMAO 13.82%, p = 0.01 and alanine 14.03%, p = 0.03) at T2. Additionally, ß-hydroxybutyrate (BHB) levels increased 10.77% in the probiotic group (p = 0.03) compared to the placebo group at T2. CONCLUSION: Supplementation with Lactobacillus acidophilus NCFM and Bifidobacterium lactis Bi-07 was able to associate with significant differences in relevant plasma metabolites associated with improved metabolic health.

Study of levan productivity from Bacillus subtilis Natto by surface response methodology and its antitumor activity against HepG2 cells using metabolomic approach.

Levan productivity of Bacillus subtilis Natto was evaluated in submerged culture varying the pH, temperature and culture time, using factorial design and response surface methodology. The characterization of levan molecular weight was performed by HPSEC and its antitumor activity against HepG2 cells using metabolomic approach was also evaluated. At first, the variables investigated, as well as their interactions, demonstrated significant effect. Further, a second design using the same variables at different levels was developed. Thus, according to the model, an optimized value corresponding to 5.82 g.L⁻¹.h⁻¹ was achieved at pH 8, 39.5°C in 21 hours, the highest value reported so far. After analysis by HPSEC, two molecular weights were obtained corresponding to 72.37 and 4146 kDa. The levan promoted an increase of acetate, alanine, lactate and phosphocreatine in HepG2 cells suggesting an alteration in the bioenergetics pathways and cellular homeostasis by intracellular accumulation of lactate, justifying its antitumor activity.