Safety Properties and Probiotic Potential of <i>Bacillus subtilis</i> KATMIRA1933 and <i>Bacillus amyloliquefaciens</i> B-1895

Abstract

This study reports on the safety and putative probiotic properties of Bacillus amyloliquefaciens B-1895 and Bacillus subtilis KATMIRA1933. According to the bacterial reverse mutation (Ames) test, cell-free supernatants of B. amyloliquefaciens B-1895 and B. subtilis KATMIRA1933 were not mutagenic. The two strains co-aggregated with Escherichia coli and Pseudomonas aeruginosa, and cell-free supernatants inhibited the growth of Streptococcus intermedius and Porphyromonas gingivalis. Endospores of B. amyloliquefaciens B-1895 and B. subtilis KATMIRA1933 were tolerant to 0.3% (w/v) bile salts and survived incubation for 4 h in MRS broth at pH 2.0 to 3.0. The ability of the two strains to produce antimicrobial compounds potentiates their application in health care formulations, personal care products, food and animal feed.

Assessment of the potential of the multi‐enzyme producer Bacillus amyloliquefaciens US573 as alternative feed additive

“…1(C), exposure at pH 2.0 for 15-30 min did not significantly affect the viability of B. amyloliquefaciens US573. However, the survival rate of this isolate at pH 2 was deeply declined when the exposure duration exceeded 1 h. These results are consistent with those observed with other Bacillus species reported to be able to withstand acidic conditions such as B. subtilis JK-04, 45 32 and Bacillus JSP1. 23 The viability of spores under such acidic conditions could be explained by the acid activation of spore germination and subsequent vegetative cell killing by simulated gastric fluids as suggested by Hong et al 46 Resistance to bile salts is a prerequisite for probiotic survival and persistence in the intestinal compartment.…”

“…In previous studies, Menconi et al . and AlGburi et al . demonstrated that B. amyloliquefaciens B2 and B. amyloliquefaciens B‐1895 were able to tolerate exposure for 2 h and 4 h, respectively, to bile at a concentration of 3 g L −1 .…”

“…The possibility of using such Bacillus ‐based probiotic preparations could be extended to humans. For example, a recent study revealed the safety of B. amyloliquefaciens B‐1895 and B. subtilis KATMIRA1933 strains to human health …”

“…For example, a recent study revealed the safety of B. amyloliquefaciens B-1895 and B. subtilis KATMIRA1933 strains to human health. 32 The B. amyloliquefaciens US573 strain isolated from geothermal soil located in southern Tunisia was previously reported to produce extremely salt-tolerant and highly thermostable extracellular phytase with high potential for application as an additive in the feed industry. 33 The objective of the present study was to evaluate the potential of this phytase-producing Bacillus as DFM for broiler based on in vitro probiotic properties such as susceptibility to antibiotics, acid and bile tolerance, deficiency in production of harmful enzymatic activities, biofilm synthesis and adhesion to chicken enterocytes; as well as the ability to produce additional extracellular enzymes like xylanase, -glucanase and amylase, involved in hydrolyzing the antinutritional factors present within feed ingredients and increasing the bioavailability of nutrients.…”

Selection of Bacillus subtilis US191 as a mannanase‐producing probiotic candidate

“…In order to characterize the five Bacillus strains in term of possible acquired antibiotic resistances, we assessed the inhibitory spectrum of these isolates to representative antibiotics. The results shown in Table indicate that all the tested strains were sensitive to the totality of checked antibiotics, which presumes their inability to transfer antibiotic resistance determinants .…”