A research on degradation of aflatoxin B1 from various foods by flavobacterium aurantiacum

In this study, the ability of Flavobacterium aurantiacum NRRL B-184 strain to remove aflatoxin B1 in potassium phosphate buffer (PPB) solution and dry red pepper, corn, olive, soy bean, dry fig and also hazelnut, was investigated.The activated F. aurantiacum NRRL B-184 strain was incubated in triptic soy broth (TSB) at 30°C and growing curve was obtained. According to non-linear regression analysis, Modified Gompertz model was fitted best with experimental data. The maximum specific growing rate (µmax) and lag time (?) were found as 0.073 h-1 and 5.244 h, respectively. It was observed that F. aurantiacum NRRL B-184 strain increased by 2.7 log and reached to the stationary phase within 45 h. The bacteria were still in that phase at 95 h.During incubation, aflatoxin B1 contents of control samples were not changed significantly. However in PPB and food mediums, the level of aflatoxin B1 was decreased continuously. This situation was indicated that, the reduction of aflatoxin B1 content was relevant to the activity of F. aurantiacum NRRL B-184 cells.First order reaction kinetics was fitted best with the reduction kinetics. In PPB medium, the ?k value? was found higher and followed by milled dry fig and whole olive. Also, the lower ?k value? was found in soy bean samples.At the end of incubation, the reduction of aflatoxin B1 content were resulted in the rate of % 84.28 and % 98.84 at whole soy bean (1000 ng g-1 AFB1) and milled hazelnut (500 ng g-1AFB1), respectively.After incubation (72 h), aflatoxin content of milled red pepper, dry fig and hazelnut that contain 500 ng g-1 aflatoxin B1 and also whole hazelnut (1000 ng g-1 aflatoxin B1) decreased to permitted level of this toxin in Turkish Food Codex.