Biological Degradation of Aflatoxin B1 by Cell-Free Extracts of Bacillus velezensis DY3108 with Broad PH Stability and Excellent Thermostability

Abstract

(1) Background: Aflatoxin contamination in food and grain poses serious problems both for economic development and public health protection, thus leading to a focus on an effective approach to control it; (2) Methods: Aflatoxin B1 (AFB1) degrading bacteria were isolated using a medium containing coumarin as the sole carbon source, and the biodegradation of AFB1 by the isolate was examined by high performance liquid chromatography, and liquid chromatography mass spectrometry; (3) Results: a bacterial strain exhibiting strong AFB1 degradation activity (91.5%) was isolated and identified as Bacillus velezensis DY3108. The AFB1 degrading activity was predominantly attributed to the cell-free supernatant of strain DY3108. Besides, it was heat-stable and resistant to proteinase K treatment but sensitive to sodium dodecyl sulfate treatment. The optimal temperature for the maximal degradation of AFB1 was 80 °C. Even more notable, the supernatant showed a high level of activity over a broad pH (4.0 to 11.0) and exhibited the highest degradation (94.70%) at pH 8.0. Cytotoxicity assays indicated that the degradation products displayed significantly (p < 0.05) lower cytotoxic effects than the parent AFB1; (4) Conclusions: B. velezensis DY3108 might be a promising candidate for exploitation in AFB1 detoxification and bioremediation in food and feed matrices.

Antimicrobial Bacillus velezensis HC6: production of three kinds of lipopeptides and biocontrol potential in maize

“…Bacillus velezensis HC6 exhibited antagonistic activity against L. monocytogenes , M. flavus and B. cereus , and a broad range of fungal pathogens, including A. flavus , A. parasiticus , A. ochraceus , A. sulphureus , F. graminearum and F. oxysporum , which often cause contamination of animal feed and affect the health and productivity of animals in poultry farming (Guerre ; Neme and Mohammed ). It has been reported that B. velezensis DY3108 could inhibit the growth of A. flavus and A. parasiticus (Shu et al ), and B. velezensis LM2303, BS87 and RK1 showed antifungal activity towards F. graminearum and F. oxysporum (Nam et al ; Chen et al ). These results support our conclusion that B. velezensis HC6 is potential to be used to reduce crop contaminations caused by pathogenic fungi.…”

Transcriptome Sequencing Revealed an Inhibitory Mechanism of Aspergillus flavus Asexual Development and Aflatoxin Metabolism by Soy-Fermenting Non-Aflatoxigenic Aspergillus

“…Due to the efficient elimination of mycotoxins and to the desire for a safe food supply, biological control represents an attractive choice. A range of microbes, such as bacteria [ 9 , 10 , 11 ], yeast, and fungi (e.g., nontoxigenic Aspergillus ), have been used for biocontrol aflatoxigenic Aspergillus [ 12 ]. Several biological control strategies to reduce AF contamination have been developed, including the use of non-toxic A. flavus and other fungi to inhibit aflatoxin synthesis [ 13 ].…”

Effect of Bacillus velezensis to substitute in-feed antibiotics on the production, blood biochemistry and egg quality indices of laying hens

“…Bacillus velezensis has been widely used as a biological control agent in agricultural elds due to its excellent ability to suppress plant diseases [24,25]. It is considered as a potential rhizobacterial organism with extraordinary biosynthetic machinery, which can trigger innate immunity in plants [26].…”