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Background: Soumbala is a highly loved alkaline traditional fermented food condiment in Burkina Faso. It harbors various microbiota dominated by fermentative Bacillus spp. as functional microorganism with little confirmed health-promoting properties. Methods: The present study aimed to evaluate six Bacillus strains previously isolated and identified from soumbala. These strains were selected as presumptively safe bacteria for probiotic and technological characteristics. These strains were assessed for in vitro probiotic criteria (tolerance to acidic pH, gastric juice, 0.3% (m/v) bile salts, intestinal juice and 0.4% (w/v) phenol, cell surface hydrophobicity, auto-aggregation capacity, antimicrobial activity against foodborne pathogens, antibiotic susceptibility and biofilm production) and technological properties, including protease, amylase, lipase, and tannase activity, as well as poly-γ-glutamic acid (PGA) production and thermo-tolerance. Results: All tested Bacillus strains (B54, F20, F24, F21, F26 and F44) presented variable relevant probiotic properties (good tolerance to pH 2 and pH 4, gastric juice, bile salts, intestinal juice and phenol), with marked differences in hydrophobicity and auto-aggregation capacity ranging from 73.62—94.71% and 49.35—92.30%, respectively. They exhibited a broad spectrum of activity against foodborne pathogens depending on target pathogen, with the highest activity exhibited by strain F20 (29.52 mm) against B. cereus 39 (p < 0.001). They also showed good biofilm production as well as variable hydrolytic enzyme activities, including protease (43.00—60.67 mm), amylase (22.59—49.55 mm), lipase (20.02—24.57 mm), and tannase (0—10.67 mm). All tested Bacillus strains tolerated temperature up to 50 °C, while only strains F26 and F44 showed the best PGA production. Conclusion: Overall, the tested cultures exhibiting potential probiotic and technological characteristics; particularly B. cereus F20, B. benzoevorans F21, B. cabrialessi F26, and B. tequilensis F44 could be a source of probiotic-starters of commercial interest in the production of high-quality soumbala. [ABSTRACT FROM AUTHOR]

Mantchoua is a fermented seed condiment produced from kapok tree (Ceiba pentandra) seeds in Burkina Faso. In this study, the microbiology of Mantchoua from raw material to final product was investigated in samples from two production sites (Pô and Bobo-Dioulasso). Four processing methods of Mantchoua production were characterized by determination of numbers of Aerobic Mesophilic Bacteria (AMB), Bacillus spp. and pH. A total of 251 Bacillus spp. from 619 AMB isolates were identified using M13-PCR and ITSPCR typing, 16S rRNA and gyrA gene sequencing. AMB and Bacillus spp. counts in raw material ranged between 4.2-4.7 log10 CFU/g and 3.8-4.1 log10 CFU/g in kapok seeds and between 2.2-2.3 log10 CFU/g and 1.1-1.8 log10 CFU/g in ash lye solution, respectively. Microbial counts in seeds mash during fermentation ranged between 9-10.9 log10 CFU/g for AMB and between 8.6-10.5 log10 CFU/g for Bacillus spp. In dried Mantchoua, AMB counts ranged between 7.7-10.4 log10 CFU/g while Bacillus spp. counts ranged between 7.5-10.3 log10 CFU/g. The fermentation of Mantchoua involved different species of Bacillus spp. At Bobo-Dioulasso pilot plant, B. subtilis subsp. subtilis dominated (50% of the Bacillus isolates) followed by B. cereus sensu lato (28% of the Bacillus isolates) while at Pô traditional production site, B. cereus sensu lato dominated (54% of the Bacillus isolates) followed also by B. subtilis subsp. subtilis (26% of the Bacillus isolates). For the Mantchoua processes including ash lye solution, pH were consistently higher during fermentation (pH 8.6-8.9), and the number of isolated B. cereus sensu lato were lower. [ABSTRACT FROM AUTHOR]

Forty Bacillus isolates obtained from maari (used as condiment in Burkina Faso) including 17 B. subtilis, 4 B. circulans, 7 B. pumilus and 6 B. licheniformis were investigated for use as starter cultures in maari production. The isolates were screened by PCR for the sfp gene responsible for the production of the lipopeptide biosurfactant, surfactin. The sfp gene was detected in all of the seventeen B. subtilis isolates, in 2 out of 7 B. pumilus, in 4 out of 6 B. licheniformis whereas no B. circulans was positive for the sfp gene by PCR screening. Furthermore, all the 40 Bacillus spp. were screened for biosurfactant production and inhibitory activity against Aspergillus flavus, A. niger, A. versicolor and Rhizopus oryzae. Results demonstrated a relationship between the presence of the sfp gene and the antifungal activity and biosurfactant production of Bacillus isolates. In addition, molecular typing of the 17 B. subtilis isolates by Multilocus Sequence Typing (MLST) resulted in 15 Sequence Types, one of them included three strains. Randomly Amplified Polymorphic DNA-PCR (RAPD-PCR), used for B. licheniformis, B. megaterium, B. circulans and B. pumilus revealed that the inhibitory activity and biosurfactant production were strain-dependent. Finally, the detection of chitinase (chi) and β-glucanase (glu) biosynthesis genes was found to be associated with the antifungal activity for 16 B. subtilis isolates. The present work provides a greater understanding of the antifungal activity and biosurfactant production ability within the Bacillus spp. isolated from maari and contributes to the selection of Bacillus isolates to be used as starter cultures for controlled production of maari., (Copyright © 2017 Elsevier GmbH. All rights reserved.)