The Study Of Toxicity Detection Of Simulating Frying Oil Withames Test

With the complexity of gutter oil source, it is hard to detect it，s hazardous ingredient indetails, Ames test can detect substances potentially harmful to human, and detect a very widerange,the rate of detection is very high. Typically, there are four main sources of waste oil:swill, repeated frying oils, animal dander offal stewed oil, oil refining from grease of sewerfloating.The oil is varied,it is mainly divided into vegetable and animal oils.In order to studythe mutagenic experiment that several repeated household cooking oil，s hazardous substancesproduced by the heating process,imitate Chinese food cooking habits, in the simulation of theproduction of waste oil, repeated cross frying food such as starch, proteins,in order toachieve the purpose of the preliminary simulation of waste oil.1.Before the four strains applied to Ames test, the characteristics of the first strain wasidentified:1)histidine dependence;2)rfa marker;3)presence of plasmid pKM101(ampicillinresistance);4)UV sensitivity(uvrB deletion);5)presence of plasmid pAQ1(Tetracyclineresistance);6)spontaneous mutant frequency. Tests showed that four strains characteristicsmeet the test requirements.2.With the non-activated plate incorporation assay, tested four simulated waste oil forfrying prepared mutagenicity and compared the strength of different oils mutagenicity,mutagenic type and mutagenic sites.It is showed that among four kinds of frying oil, friedlard, fried corn oil only lead TA97, TA100mutation, mutation of G-C, the type of basesubstitution mutation or frameshift mutations;Canola oil for frying, peanut oil for frying inaddition to cause a frameshift mutation occurs at G-C, but also lead to A-T base pairsubstitution, the latter can also lead to G-C base substitution mutation.Therefore, under thesame simulation conditions, as a reference to the number of mutation types,the relationshipbetween the size of the four gutter oils mutagenicity is: peanut oil for frying> canola oil forfrying>lard for frying> corn oil for frying.3.With a separate frying lard, lard mixed with peanut oil for frying simulated cookingsituations in life that separate frying animal oil and frying animal oil mixed with vegetable oil.The non-activated plate incorporation test method was used to test two simulated oil mutagenicity,the results showed: both can lead to TA97mutations, but a separate frying lardcan also lead TA102mutation occurs, this indicated that the use of lard alone in the cookingprocess can produce more toxic substances.4.Use TA100strain, the test measured lard sampling mutagenicity heated at differenttimes,it is showed that at the same dose level, the overall obviously performanced that withan extension of heating time, induced TA100revertant colonies comparison with thenegative number, the ratio is of corresponding increases until heated6h, the ratio is greaterthan2, these indicated that accumulation of mutagens at the beginning of the heating6h caninduce mutations.5.Extended the experiment observation time48h to72h, in four kinds of oil mutagenesisexperiments，compared the ratio of the48h observed colonies with the negative control foreach dose, but found that the ratio of72h is lower than48h, this verified that48h observationtime is rational.6.Use TA102strain,As a control group,untreated oil which added Tween80was liquidcultured treated oil which added Tween80was liquid cultured as the experimentalgroup,Liquid culture4h and8h, diluted10-fold and100-fold, then coated plate, cultured in37℃for48h then counts.The results showed that the oil sample plus Tween80solutionculture mutagenicity tests are consistent with the results of the plate incorporationassay.However, this method may detect a mutagen which can not be dissolved in the solvent.7.With the same concentration of carboxymethyl cellulose to replace agar, as curing agent,added to the top agar medium for Ames test,the results showed that growth of colonies inplate which added carboxymethyl cellulose was uniform,also most colonies radius is ofgreater than2mm.But slow curing, flat non-inversion cultivation, it is needed to furtherexplore solutions to optimize test conditions.