Stability Of Bound AFB₁ And T-2 Toxins In Dried Red Fish And Evaluation Of Their Toxic Effects On Mice

Dried red fish is an important economic aquatic product in the South China Sea.It’s mainly salted with light salt and dehydrated in the sun.It’s characterized by low salt and high protein.Dried red fish in the production,storage,transportation,distribution,and easy processing by exogenous pollution,which can lead to food safety issues,and fungal toxin is one of the common pollutants,according to the statistics,Aspergillus species（Aspergillus SPP.）and Fusarium oxysporum（Fusarium SPP.）,the pollution is more serious,and aflatoxin B₁（AFB₁）and T-2 toxin（T-2）pollution phenomenon is relatively common.AFB₁and T-2 have hepatotoxicity and hemotoxicity.Studies have shown that AFB₁and T-2 toxins can combine with proteins,glucose,fatty acids,hemicellulose and other substances in the defense mechanism of some yeast,bacteria and filamentous fungi,in the defense mechanism of plants,in the metabolic process of mammals or in the food processing process to form the binding AFB₁and T-2 toxins.However,the bound AFB₁and T-2 toxins can be converted into free AFB₁and T-2 under the action of microorganisms or digestive enzymes.Therefore,long-term consumption of food contaminated with combined AFB₁and T-2 will bring potential food safety risks.In this study,AFB₁and T-2 mycotoxins with high pollution in red fish stem were selected.AFB₁and T-2 with concentrations of 25 ng/m L,50 ng/m L,100 ng/m L and 200ng/m L were mixed with dried red fish powder,respectively,and then incubated for 0 min,20 min,40 min and 60 min.After using different methods such as trifluoroacetic acid（TFA）dissociation,artificial gastric juice dissociation,artificial intestinal juice dissociation,LC-MS/MS were used to detect the content of free AFB₁&T-2 toxin in dried red fish powder,to explore different incubation time and solution from the way of combination of AFB₁and T-2 toxin formation rule.The dose of 400 ng/kg of AFB₁,T-2,dried red fish powder+AFB₁of mixture,dried red fish powder+T-2 of mixture lavage SPF mice,records of mice weight every day,7 days later take the liver weight,liver weight and body weight growth rate calculation,and determination of 4 kinds of liver enzyme activity and blood routine index,to explore the liver toxicity and blood toxicity of bound AFB₁and T-2 in mice.Conclusion:（1）The formation of bound AFB₁and T-2 toxins in dried red fish:（1）（1）With the extension of incubation time,the binding rate of AFB₁and T-2 gradually increased by34.89-87.78%（P<0.05）,indicating that after incubation,AFB₁and T-2 can form a combination with dried red fish,and the bound toxin will be combined with the extension of time gradually increase.（2）With the increase in the amount of toxin added,the binding rate of AFB₁increased by 1.06-4.9%（P<0.05）,and the binding rate of T-2 decreased by3.86-12.76%（P<0.05）.As the toxin concentration increased,the amount of bound AFB₁increased significantly,and the bound T-2 The amount is significantly reduced..（2）Stability of bound AFB₁and T-2 toxins in dried red fish:（1）Trifluoroacetic acid could promote the formation of binding state and the dissociation of binding state of AFB₁and T-2 toxin formed in dried red fish powder stem under different incubation time and different addition amount.（2）Artificial gastric juice can reduce the binding rate of AFB₁and dried red fish powder,and the binding rate of T-2 and dried red fish powder by9.48-72.10%（P<0.05）,indicating that artificial gastric juice can significantly reduce the stability of bound AFB₁and T-2.（3）Artificial intestinal juice can reduce the binding rate of AFB₁and dried red fish powder,and the binding rate of T-2 and dried red fish powder by3.70-72.46%（P<0.05）,indicating that artificial intestinal juice can significantly reduce the stability of bound AFB₁and T-2.（3）Liver toxicity of combined AFB₁and T-2 toxin in red fish:（1）Bound T-2 can increase the activity of ACP and AST in mice by 10.9-26.7%（P<0.05）,（2）The growth rate of mouse body weight decreased by 6.18-7.47%after being fed with bound AFB₁and T-2for 7 days（P<0.05）,（3）The bound AFB1 significantly increased the liver weight ratio of mice by 92.5%（P<0.05）.It shows that the combined state of AFB₁and T-2 in dried red fish has liver toxicity..（4）Hematological toxicity of bound AFB₁and T-2 toxin in dried red fish:（1）Bound AFB1 and T-2 make mice white blood cell count（WBC）,mononcyte ratio（MID）,lymphocyte count（LYM）,red blood cell count（RBC）,hemoglobin concentration（HGB）,hematocrit（HCT）,erythrocyte distribution width（RDW-CV）were significantly reduced by 8.27-72.0%（P<0.05）;the mouse lymphocyte ratio（LYM）was significantly reduced Increased by 2.08-2.30%（P<0.05）;mean platelet volume（MPV）increased significantly by 74.55-194.5%（P<0.05）.（2）Bound AFB₁can also significantly reduce the width of platelet volume distribution（PDW）in mice by 20.17%（P<0.05）and the large platelets ratio（P-LCR）significantly increase by 11.20%（P<0.05）;Bound T-2 can also significantly reduce the mean erythrocyte volume（MCV）of mice by 10.84%（P<0.05）,the mean RBC hemoglobin content（MCH）by 27.38%（P<0.05）,and the erythrocyte distribution width（RDW-SD）by 6.97%（P<0.05）.