title: Biotransformation of aflatoxin B1 and aflatoxin G1 in peanut meal by anaerobic solid fermentation of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus.
abstract: The purpose of this study was to explore the ability of anaerobic solid fermentation of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus to biotransform aflatoxins in peanut meal. The pH of the peanut meal was adjusted above 10, and then heated for 10 min at 100 °C, 115 °C and 121 °C. The S. thermophilus and L. delbrueckii subsp. bulgaricus were precultured together in MRS broth for 48 h at 37 °C. The heated peanut meal was mixed with precultured MRS broth containing 7.0×10(8) CFU/mL of S. thermophilus and 3.0×10(3) CFU/mL of L. delbrueckii subsp. bulgaricus with the ratio of 1 to 1 (weight to volume) and incubated in anaerobic jars at 37 °C for 3 days. The aflatoxin content in the peanut meal samples was determined by HPLC. The results showed that the peanut meal contained mainly aflatoxin B1 (AFB1) (10.5±0.64 μg/kg) and aflatoxin G1 (AFG1) (18.7±0.55 μg/kg). When heat treatment was combined with anaerobic solid fermentation, the biotransformation rate of aflatoxins in peanut meal could attain 100%. The cytotoxicity of fermented peanut meal to L929 mouse connective tissue fibroblast cells was determined by MTT assay and no significant toxicity was observed in the fermented peanut meal. Furthermore, heat treatment and anaerobic solid fermentation did not change the amino acid concentrations and profile in peanut meal.
authors.affiliation: School of Food Science and Engineering, Ocean University of China, Qingdao, Shandong 266003, China.
authors.forename: Yujie
authors.initials: Y
authors.lastname: Chen
authors.affiliation: School of Food Science and Engineering, Ocean University of China, Qingdao, Shandong 266003, China. Electronic address: kongqing@ouc.edu.cn.
authors.forename: Qing
authors.initials: Q
authors.lastname: Kong
authors.affiliation: School of Food Science and Engineering, Ocean University of China, Qingdao, Shandong 266003, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Chi
authors.affiliation: Shandong Peanut Research Institute, Qingdao, Shandong 266110, China.
authors.forename: Shihua
authors.initials: S
authors.lastname: Shan
authors.affiliation: School of Food Science and Engineering, Ocean University of China, Qingdao, Shandong 266003, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Guan
mesh_terms: D016604:Aflatoxin B1 / Q000378:metabolism* / Q000633:toxicity; D000348:Aflatoxins / Q000378:metabolism* / Q000633:toxicity; D000693:Anaerobiosis; D000818:Animals; D010367:Arachis / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*; D001711:Biotransformation; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D005285:Fermentation; D048668:Lactobacillus delbrueckii / Q000378:metabolism*; D051379:Mice; D048249:Streptococcus thermophilus / Q000378:metabolism*
chemical_list: D000348:Aflatoxins; C027955:aflatoxin G1; D016604:Aflatoxin B1
keywords: Aflatoxin B(1); Aflatoxin G(1); Anaerobic solid fermentation; Heat treatment; MTT assay