Gratz S, Mykkänen H, El-Nezami H
Department of Clinical Nutrition, Mediteknia, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland.
J Food Prot. 2005 Nov;68(11):2470-4. doi: 10.4315/0362-028x-68.11.2470.
Aflatoxin B1 (AFB) is a well-known carcinogen and reducing its bioavailability is of great interest for human and animal health. Several probiotic bacteria are able to bind AFB1 in vitro, including Lactobacillus rhamnosus LC-705 and Propionibacterium freudenreichii subsp. shermanii JS. A mixture of these two probiotics is used by the food and feed industry as biopreservative (Bioprofit), making it a promising candidate for future applications. Consequently, this study aims to investigate the in vitro and ex vivo ability of this probiotic mixture to bind AFB1. For in vitro experiments, probiotic mixture was suspended in an AFB1 solution (5 microM), incubated for 1 to 30 min, centrifuged, and AFB1 residues were quantitated in supernatant and pellet. For ex vivo experiments, duodenal loops of chicks were ligated and injected with either AFB1 solution alone or probiotic mixture suspension and AFB1 solution. Lumen content was centrifuged and AFB1 was quantitated in supernatant and pellet. Additionally, AFB1 was extracted from duodenal tissue to calculate tissue uptake. In vitro, 57 to 66% of AFB1 was removed from the solution by the probiotic mixture, but only 38 to 47% could be extracted from the bacterial surface. In ex vivo experiments, only up to 25% of AFB1 was bound by bacteria, and tissue uptake of AFB1 was significantly reduced when probiotic bacteria were present in the duodenal loop. Furthermore, the effect of intestinal mucus on the bacterial binding ability was investigated in vitro and was found to significantly reduce AFB1 binding by the probiotic mixture. However, probiotic mixture could only retard but not prevent AFB1 absorption in duodenal loops. Further work needs to assess the potential of probiotics in different experimental setups.
黄曲霉毒素B1（AFB）是一种广为人知的致癌物，降低其生物利用度对人类和动物健康具有重要意义。几种益生菌能够在体外结合AFB1，包括鼠李糖乳杆菌LC - 705和谢氏丙酸杆菌亚种JS。食品和饲料行业将这两种益生菌的混合物用作生物防腐剂（Bioprofit），使其成为未来应用的有前途的候选者。因此，本研究旨在调查这种益生菌混合物在体外和离体条件下结合AFB1的能力。对于体外实验，将益生菌混合物悬浮在AFB1溶液（5微摩尔）中，孵育1至30分钟，离心，然后对上清液和沉淀中的AFB1残留量进行定量。对于离体实验，结扎雏鸡的十二指肠肠袢，单独注射AFB1溶液或注射益生菌混合物悬液和AFB1溶液。将肠腔内容物离心，对上清液和沉淀中的AFB1进行定量。此外，从十二指肠组织中提取AFB1以计算组织摄取量。在体外，益生菌混合物从溶液中去除了57%至66%的AFB1，但仅能从细菌表面提取38%至47%。在离体实验中，细菌仅结合了高达25%的AFB1，并且当十二指肠肠袢中存在益生菌时，AFB1的组织摄取量显著降低。此外，在体外研究了肠黏液对细菌结合能力的影响，发现其显著降低了益生菌混合物对AFB1的结合。然而，益生菌混合物只能延缓而不能阻止十二指肠肠袢中AFB1的吸收。需要进一步的工作来评估益生菌在不同实验设置中的潜力。
