Safety assessment of surfactin‐producing Bacillus strains and their lipopeptides extracts in vitro and in vivo

DI GIACOMO, A.L; AZCURRA NADIA; GARCIA G; DOGI C.A; GONZALEZ PEREYRA, MARÍA

JOURNAL OF BASIC MICROBIOLOGY

WILEY-V C H VERLAG GMBH

Lugar: Weinheim; Año: 2023

0233-111X

Beneficial Bacillus strains can be administered to livestock as probiotics toimprove animal health. Cyclic lipopeptides produced by Bacillus such assurfactins may be responsible for some of the beneficial effects due to theiranti‐inflammatory and immunomodulatory activity. The aim of the presentstudy was to isolate and evaluate the biocompatibility of native Bacillus spp.strains and their surfactin‐like lipopeptides in vitro and in vivo to determinetheir potential to be used on animals. Biocompatibility of endosporesuspensions (108 UFC/mL), and different dilutions (1:10; 1:50; 1:100; 1:500,and 1:1000) of Bacillus lipopeptide extracts containing surfactin was tested onCaco‐2 cells by microculture tetrazolium‐based colorimetric assay. Genotoxicitywas tested on BALB/c mice (n = 6) administered 0.2 mL of endosporesuspensions by the bone marrow erythrocyte micronuclei assay. Allthe isolates tested produced between 26.96 and 239.97 μg mL−1 of surfactin.The lipopeptide extract (LPE) from isolate MFF1.11 demonstrated significantcytotoxicity in vitro. In contrast, LPE from MFF 2.2; MFF 2.7, TL1.11, TL 2.5,and TC12 had no cytotoxic effect (V% > 70%) on Caco‐2 cells, not affecting cellviability signifficantly in most treatments. Similarly, none of the endosporesuspensions affected cell viability (V% > 80%). Likewise, endospores did notcause genotoxicity on BALB/c mice. This study was elementary as a first stepfor a new line of research, since it allowed us to choose the safest isolates tokeep working on the search of new potentially probiotic strains destined toproduction animals to improve their performance and health.