Si Cheng,Chao Yin,Keying Li,Zhe Liu,Qingyan Pan,Xifeng Zuo,Ailing Guo,Huawei Ma
Films with excellent mechanical properties and antimicrobial activity have potential applications in food preservation. The antimicrobial film was prepared by blending probiotic Bacillus velezensis 906 metabolites (906), potassium sorbate (PS), and polyvinyl alcohol (PVA). The film was characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermal stability analysis. The mechanical, barrier, and antimicrobial properties of the film were tested. The results of the physicochemical analysis indicated that, compared to the pure PVA film, the film's mechanical properties decreased, while its barrier properties and hydrophobicity increased with the addition of PS and 906, respectively. The results of the antimicrobial tests revealed that the blend film exhibited significant antimicrobial activity against Vibrio parahaemolyticus, Psychrobacter maritimus , Oceanobacillus kimchii, Pseudomonas aeruginosa , and Listeria monocytogenes . SEM demonstrated good fusion between the components of the PVA/PS/906 film, resulting in a dense and crack-free structure. FTIR suggested that PS and 906 enhance molecular interactions within the film matrix. XRD revealed that the film was crystallized, with 906 increasing the crystallinity of the bonds between the film components. Thermal analysis indicated the thermal stability of the films was enhanced. Consequently, the PVA/PS/906 blend film shows significant potential for application in the preservation of aquatic products.
Optimized postbiotics achieved 88.5% AFB 1 degradation with Cu 2+ or Fe 2+ . • Postbiotics attack furan and lactone rings of AFB1 to yield C 17 H 12 O 5 and C 16 H 12 O 5 . • Postbiotics reduced AFB 1 in peanut meal to below safety standard. • Postbiotics alleviated hepatic injury and inflammation in mice. • Postbiotics promoted the colonization of beneficial gut microbials. Probiotics and postbiotics offer a promising approach to decontaminate widely occurring aflatoxin B 1 (AFB 1 ). This study identified and optimized the postbiotics from Bacillus velezensis 906, systematically exploring the degradation products and pathways and evaluating the degradation efficacy and in vivo safety. The optimized postbiotics degraded 77.6% of AFB 1 in vitro , which increased to 88.5% with Cu 2+ supplementation. The degradation process involves lactone ring cleavage and furan ring modification to yield C 17 H 12 O 5 and C 16 H 12 O 5 . In moldy peanut meal, treatment merely with postbiotics and probiotics inhibited fungal growth and reduced AFB 1 from 100.86 μg/kg to 37.54 μg/kg and 45.81 μg/kg, while preserving nutritional quality. Oral gavage of moldy peanut meal treated with postbiotics significantly reduced serum alanine aminotransferase (ALT) by 29%, malondialdehyde (MDA) by 43.60% and interleukin-1β (IL-1β) by 59.8%, and normalized liver pathology and the gut microbiota ratio. In summary, B. velezensis 906 can efficiently degrade AFB 1 , ensuring the safety of moldy peanut meal for consumption while preserving its quality and nutritional value, providing an effective and safe strategy for the mycotoxin bioremediation in food and feed matrices. Download: Download high-res image (440KB) Download: Download full-size image
危险品化学品经营许可证（带存储）