The Research Of Detection Methods Of Four Mycotoxins And Detoxification Method Of OTA

Mycotoxin is the secondary metabolic product of fungus,often existing in moldy grains.Once entering human's body,it may cause serious danger,like deformity,mutation or cancer and so on.Therefore,it is fully concerned in global food security.At present,many methods are adopted in the test of Mycotoxin.HPLC is the accuratest method for the determination of Mycotoxin in foods.With different genera and species of Mycotoxins,We choose four kinds of Mycotoxins.This thesis research detection methods of the four Mycotoxins and detoxification method of OTA.A rapid and accurate method for the determination of ochratoxin A(OTA)in foods was established.Samples were extracted by methanol-water or NaHCO3 solution.After dilution the extracts,flowed through a OchraTest column containing specific antibody of OTA.The column was eluted with PBS buffer,OTA buffer,pure water,and methanol in turn.The methanol eluate was separated on CT8(150×4.60 mm,5μm)at 35℃with acetonitrile-water-acetic acid(99:99:2,V/V)as mobile phase at the elution flow rate 0.90 ml/min.The excitation wavelength of fluorescence detector was 333 nm and the emission wavelength was 477 nm.It was found that there is a good linear relationship between the peak area and the concentration.The recoveries of OTA are 90.3%to 106%,and the relative standard deviations are 1.75% to 4.32%for different kinds of food sample.The method is simple,rapid,accurate and applicable for the determination of OTA in foods.A rapid and accurate method for the determination of T-2 toxin(T-2)in foods was established.Samples were extracted by methanol-water solution.After dilution the extracts,flowed through a OchraTest column containing specific antibody of T-2. The methanol eluate was derivatived with 1-AN and was separated on C18(150×4.60 mm,5μm)at 35℃with acetonitrile-water(75:25,V/V)as mobile phase at the elution flow rate 1.0 ml/min.The excitation wavelength of fluorescence detector was 381 nm and the emission wavelength was 470 nm.It was found that there is a good linear relationship between the peak area and the concentration.The recoveries of T-2.are 82.6%to 103.2%,and the relative standard deviations are 1.9% to 5.6%for different kinds of food sample.The method is simple,rapid,accurate and applicable for the determination of T-2.in foods.A rapid and accurate method for the determination of Zearalenone(ZEN)in foods was established.Samples were extracted by acetonitrile-water solution.After dilution the extracts,flowed through a OchraTest column containing specific antibody of ZEN.The methanol eluate was separated on C18(150×4.60 mm,5μm)at 35℃with acetomtrile-water-methanol(46:46:8,V/V)as mobile phase at the elution flow rate 1.0 ml/min.The excitation wavelength of fluorescence detector was 274 nm and the emission wavelength was 440 nm.It was found that there is a good linear relationship between the peak area and the concentration.The recoveries of ZEN are 69.3%to 101.3%,and the relative standard deviations are5.0%to 11.6%for different kinds of food sample.The method is simple,rapid,accurate and applicable for the determination of ZEN in foods.A rapid and accurate method for the determination of Deoxynivalenol(DON)in foods was established.Samples were extracted by Polyethylene glycol-water solution. After dilution the extracts,flowed through a OchraTest column containing specific antibody of DON.The methanol eluate was separated on C18(150×4.60 mm,5μm)at 35℃with methanol-water-(20:80,V/V)as mobile phase at the elution flow rate 1.0 ml/min.The detection wavelength of UV detector was 218 nm.It was found that there is a good linear relationship between the peak area and the concentration.The recoveries of DON are 65.8%to 85.9%,and the relative standard deviations are 3.1% to 6.8%for different kinds of food sample.The method is simple,rapid,accurate and applicable for the determination of DON in foods.ochratoxin A(OTA)is the most widely distributed in nature and the most toxic toxin.The fittest Ochratoxin degradation and adsorption is the microbe degradation and adsorption.Ochratoxin degrading and adsorbing activities of several strains were tested.We find that P.rhodozyma is the best strains for Ochratoxin degradation and adsorption,The data presented indicate that P.rhodozyma is able to convert ochratoxin A to ochratoxin a.Also we have a conditions optimization of degradation,P. Rhodozyma have the highest activities at 30℃,P.Rhodozyma degraded more than 80%of ochratoxin A in 13 days at 25～35℃.