Antimicrobial activity of Bacillus subtilis and Bacillus pumilus during the fermentation of African locust bean (Parkia biglobosa) for Soumbala production

Abstract

Aims: To examine predominant isolates of Bacillus subtilis and B. pumilus isolated from Soumbala for their antimicrobial activity against indicator microorganisms as Micrococcus luteus, Staphyloccocusaureus, Bacillus cereus, Enterococus facium, Listeria monocytogenes, Escherichia coli, Salmonella typhimurium, Shigella dysenteriae, Yersinia enterocolitica, Aspergillus ochraceus and Penicillium roqueforti. Methods and Results: Growth inhibition of indicator microorganisms by cells and supernatants of three B. subtilis and two B. pumilus strains was investigated using agar diffusion tests. Inactivation of indicator microorganisms was investigated in laboratory broth and during the fermentation of African locust bean for Soumbala production. The Bacillus isolates showed variable ability of inhibition and inactivation according to the indicator microorganism. The supernatants of pure cultures of B. subtilis inhibited one strain of B. cereus, one of Staph. aureus and E. coli and caused abnormal germination of Aspergillus ochraceus. The supernatant of mixed cultures of B. subtilis and indicators inhibited all the indicators. A treatment with protease eliminated the inhibitions. Isolates of B. subtilis inactivated all the indicators organisms during the fermentation of African locust bean as well as in laboratory broth with about five to eight decimal reduction. Conclusion: Bacillus isolates from Soumbala inhibit and inactivate Gram‐positive and Gram‐negative bacteria as well as ochratoxin A producing fungi during both laboratory cultivation and natural fermentation. Significance and Impact of the Study: Selection of starter cultures of Bacillus spp. for controlled production of Soumbala.

Antagonistic Activity of Bacillus Bacteria against Food-Borne Pathogens

“…Bacillus bacteria are known to be effective antagonists of different pathogens [15,24]. In recent years bacilli were extensively studied as probiotics, due to their health benefits on the host [25,26].…”

Characterization of Proanthocyanidins from Parkia biglobosa (Jacq.) G. Don. (Fabaceae) by Flow Injection Analysis — Electrospray Ionization Ion Trap Tandem Mass Spectrometry and Liquid Chromatography/Electrospray Ionization Mass Spectrometry

“…The fermented seed (known as dawadawa or soumbala) is a popular, protein-rich condiment in many Western African countries [3,4]. Studies with species of the genus Parkia showed that most of them have antioxidant [5], antimicrobial [6,7], gastroprotective [8] and some antihypertensive effects [9]. Previous phytochemical investigations of P. biglobosa reported that sterols, triterpenes [10], catechins and phenolic derivatives could be isolated from the bark [11], and fatty acids from the seed oil of this species [12].…”

Potential Spore-Forming Probiotics Isolated from Ntoba mbodi, Alkaline Fermented Leaves of Cassava from the Republic of the Congo

“…This alkalization of the fermentation medium acts as a selective factor for alkaline-tolerant bacteria such as Bacillus spp [28]. The demonstration of the pectinolytic activity of strains suggests that spore-forming strains are also capable of degrading the skeletal structures of the cassava leaves cell wall and as consequence contributing to the softening of food.…”