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Article | Open Access

Metabolic characterization of selected probiotic consortia during gluten and wheat bread simulated digestion

Mirco Vaccaa,1, Giuseppe Celanoa,1, Olga Nikoloudakib, Bodo Speckmannc, Francesco Maria Calabresea(), Marco Gobbettib, Maria de Angelisa
Department of Soil Plant and Food Sciences, University of Bari Aldo Moro, Bari 70126, Italy
Faculty of Science and Technology, Free University of Bozen, Bolzano 39100, Italy
Evonik Operations GmbH, Hanau-Wolfgang 63457, Germany

1 These authors have contributed equally to this work.

Peer review under responsibility of Beijing Academy of Food Sciences.

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Highlights

• An innovative consortium accounting for the combination of probiotics and microbial enzymes completely metabolizes 10 grams of gluten in less than 24 hours of simulated digestion.

• The innovative probiotic consortium in vitro also showed beneficial properties in terms of antioxidant, phytase, and anti-inflammatory activity.

• Gluten and breads digested by the innovative probiotic consortium did not determine an altered cytokines expression in biopsies of celiac disease patients compared against cells not exposed to gluten.

• Targeting the field of personalized nutrition, the innovative probiotic consortium can be used as an adjuvant in patients with celiac disease and gluten-based disorders to reduce many of the adverse symptoms resulting from accidentally exposure to gluten.

Abstract

While exerting their metabolic activities in the gastrointestinal milieu, probiotics impact the host well-being by boosting immunity, treating metabolic disorders, and modulating microbiota and metabolome. Due to the high incidence of gluten-based disorders, the present work aims to deeply explore the metabolism of two selected microbial consortia (MCs) during gluten digestion under simulated gastrointestinal conditions. Featured by high protease and peptidase activity, both MCs accounted for different lactic acid bacteria and Bacillus strains that were combined with two commercial protease enzymes. Gluten substrates were used as purified extracts, white and whole wheat breads. Control samples, instead, relied onto the microbial enzyme lack. Twenty-four hours of simulated digestion were sufficient to completely hydrolyze gluten in one of the two MC-containing experimental sets, and the relative 48 h-digested extract did not alter the cytokine expression in duodenal biopsies from celiac disease (CeD) patients. When digested samples were assayed for antioxidant and phytase activities, microbial enzymes demonstrated to significantly improve both 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity and to decrease the phytic acid concentration. The inspection of the free amino acid profiles allowed for distinguishing the two MCs, whereas the detection of a heterogeneous panel of volatile organic compounds supported the presence/activity of microbial enzymes without statistically significant differences between MCs. As functional contribution, digested extracts with MCs also proved to reduce the inflammatory cytokine concentrations in cell lines exposed to lipopolysaccharide trigger. Therefore, in line with studies exploring novel adjuvant therapies, the present innovative probiotic consortium featured by high gluten-hydrolyzing metabolism also showed the capability to improve various parameters usually found to be altered in patients affected by gluten-based disorders or CeD.

Keywords

ProbioticsGluten metabolismBacterial peptidasesPersonalized nutritionAdjuvant therapy

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Food Science and Human Wellness
Volume 14 Issue 2,
February 2025
Article number: 9250033
DOI: 10.26599/FSHW.2024.9250033
Cite this article:
Vacca M, Celano G, Nikoloudaki O, et al. Metabolic characterization of selected probiotic consortia during gluten and wheat bread simulated digestion. Food Science and Human Wellness, 2025, 14(2): 9250033. https://doi.org/10.26599/FSHW.2024.9250033
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Hydrolyzed gluten concentrations (ppm) at different time-points of simulated gastrointestinal digestion.

Groups Hydrolyzed gluten 6 h 16 h 24 h 36 h 48 h
Note: Simulated gastrointestinal digestion expressed as mean value ± standard deviation. Substrates included 10 g of gluten (CG), gluten from 100 g of white wheat bread (CB) and gluten from 100 g of whole wheat bread (CWB). Control samples were tested with or without the addition of two commercial enzymes (Tolerase G® and PromodTM) and they did not contain any microbial enzyme. The MCs (MC12 and MC16) contained both alive and lysed cells of selected LAB and Bacillus strains, and commercial enzymes. Considering the same substrate (CG, CB, or CWB) and the same time of digestion (6, 16, 24, 36, or 48 h), different superscript letters indicate a significant difference (P < 0.05; two-ways ANOVA). Same as in Table 2.
CG CG 798.4 ± 4.1a 745.9 ± 12.2a 675.9 ± 4.1a 567.3 ± 7.1a 555.9 ± 12.2a
CG-Promod 599.6 ± 7.1c 551.1 ± 7.1b 435.7 ± 7.1c 372.9 ± 1.0b 335.4 ± 7.1b
CG-Tolerase 646.2 ± 2.0b 520.9 ± 4.1b 515.9 ± 2.0b 372.9 ± 4.1b 332.1 ± 4.1b
CG-Promod-MC12 252.2 ± 3.1c 245.3 ± 6.1c 243.2 ± 3.1d 372.9 ± 9.2b 236.7 ± 6.1c
CG-Promod-MC16 276.6 ± 11.2c 178.5 ± 10.2d 145.4 ± 0.0e 72.9 ± 3.1d 78.7 ± 10.2e
CG-Tolerase-MC12 246.9 ± 9.2c 231.2 ± 6.1c 227.9 ± 9.2d 201.7 ± 5.1c 131.7 ± 6.1d
CG-Tolerase-MC16 270.6 ± 2.0c 223.8 ± 8.2c 213.1 ± 0.0d 66.9 ± 2.0d 55.0 ± 8.2e
CB CB 774.3 ± 5.1a 623.1 ± 9.2a 609.5 ± 5.1a 534.9 ± 8.2a 441.2 ± 9.2a
CB-Promod 609.0 ± 3.1b 546.8 ± 11.2b 515.7 ± 3.1b 399.7 ± 3.1b 339.1 ± 11.2b
CB-Tolerase 426.1 ± 10.2c 420.4 ± 5.1c 315.8 ± 10.2c 322.1 ± 11.2c 225.4 ± 5.1c
CB-Promod-MC12 236.2 ± 2.0d 232.1 ± 4.1d 254.0 ± 2.0d 230.0 ± 5.1d 209.3 ± 4.1c
CB-Promod-MC16 263.3 ± 4.1d 177.4 ± 0.0e 169.6 ± 0.0e 64.5 ± 0.0e 50.3 ± 11.2d
CB-Tolerase-MC12 238.3 ± 1.0d 233.7 ± 7.1d 231.4 ± 1.0d 231.9 ± 8.2d 229.8 ± 7.1c
CB-Tolerase-MC16 233.3 ± 5.1d 218.7 ± 0.0d 194.3 ± 0.0e 22.9 ± 0.0f 14.2 ± 5.1e
CWB CWB 698.5 ± 9.2a 675.1 ± 4.1a 599.3 ± 9.2a 523.1 ± 4.1a 432.1 ± 4.1a
CWB-Promod 603.2 ± 7.1b 510.8 ± 9.2b 435.2 ± 7.1b 388.0 ± 7.1b 342.7 ± 9.2b
CWB-Tolerase 430.6 ± 4.1c 424.2 ± 2.0c 322.1 ± 4.1c 305.9 ± 2.0c 214.2 ± 2.0c
CWB-Promod-MC12 372.9 ± 5.1c 260.1 ± 3.1d 259.5 ± 5.1d 257.5 ± 6.1d 246.2 ± 3.1c
CWB-Promod-MC16 280.0 ± 9.2d 274.2 ± 9.2d 184.2 ± 0.0e 72.9 ± 0.0e 32.4 ± 9.2e
CWB-Tolerase-MC12 255.1 ± 2.0d 235.9 ± 6.1d 204.0 ± 2.0e 192.5 ± 3.1d 192.1 ± 6.1d
CWB-Tolerase-MC16 191.2 ± 1.0e 188.3 ± 0.0e 185.0 ± 0.0e 21.9 ± 0.0f 19.7 ± 7.1e

Residual gluten concentration (ppm) at different time-points of simulated gastrointestinal digestion.

Groups Residual gluten 6 h 16 h 24 h 36 h 48 h
Note: The asterisk (*) indicates the complete gluten hydrolysis (absence of residual gluten).
CG CG 763.8 ± 12.2a 681.5 ± 4.1a 618.4 ± 12.2a 571.4 ± 7.1a 425.8 ± 4.1a
CG-Promod 740.4 ± 7.1a 571.4 ± 7.1b 384.3 ± 7.1b 360.2 ± 1.0b 254.9 ± 7.1b
CG-Tolerase 698.4 ± 4.1b 574.1 ± 2.0b 402.8 ± 4.1b 349.9 ± 4.1b 193.4 ± 2.0c
CG-Promod-MC12 295.2 ± 6.1c 217.8 ± 3.1c 169.7 ± 6.1c 107.3 ± 9.2c 64.7 ± 3.1d
CG-Promod-MC16 103.9 ± 10.2e 85.7 ± 11.2d 7.7 ± 10.2d 6.9 ± 3.1d 0*
CG-Tolerase-MC12 261.1 ± 6.1c 235.7 ± 9.2c 189.5 ± 6.1c 108.8 ± 5.1c 54.3 ± 9.2d
CG-Tolerase-MC16 147.2 ± 8.2d 101.6 ± 2.0d 26.5 ± 8.2d 4.7 ± 2.0d 0*
CB CB 677.3 ± 9.2a 580.5 ± 5.1a 573.5 ± 9.2a 400.1 ± 8.2a 238.1 ± 5.1a
CB-Promod 527.1 ± 11.2b 321.4 ± 3.1b 229.0 ± 11.2b 193.4 ± 3.1b 133.8 ± 3.1b
CB-Tolerase 516.3 ± 5.1b 374.1 ± 10.2b 238.1 ± 5.1b 197.6 ± 11.2b 140.6 ± 10.2b
CB-Promod-MC12 275.8 ± 4.1c 194.6 ± 2.0c 145.2 ± 4.1c 65.1 ± 5.1c 35.5 ± 2.0c
CB-Promod-MC16 48.6 ± 11.2d 2.2 ± 4.1d 0* 0* 0*
CB-Tolerase-MC12 301.4 ± 7.1c 216.8 ± 1.0c 194.8 ± 7.1b 69.1 ± 8.2c 43.8 ± 1.0c
CB-Tolerase-MC16 67.0 ± 5.1d 6.6 ± 5.1d 0* 0* 0*
CWB CWB 698.6 ± 4.1a 597.1 ± 9.2a 575.0 ± 4.1a 383.6 ± 4.1a 296.9 ± 9.2a
CWB-Promod 572.7 ± 9.2b 406.9 ± 7.1b 275.8 ± 9.2b 195.2 ± 7.1b 149.1 ± 7.1b
CWB-Tolerase 549.9 ± 2.0b 364.5 ± 4.1b 245.2 ± 2.0b 191.2 ± 2.0b 157.9 ± 4.1b
CWB-Promod-MC12 280.3 ± 3.1c 237.6 ± 5.1c 195.3 ± 3.1c 153.0 ± 6.1c 45.9 ± 5.1d
CWB-Promod-MC16 98.4 ± 9.2d 20.1 ± 9.2e 2.8 ± 9.2d 0* 0*
CWB-Tolerase-MC12 299.1 ± 6.1c 271.2 ± 2.0c 210.2 ± 6.1c 136.4 ± 3.1c 66.8 ± 2.0c
CWB-Tolerase-MC16 103.0 ± 7.1d 64.7 ± 1.0d 0* 0* 0*