Biological Control Technology Of Escherichia Coli In Pneumatophorus Japonicus

In order to solve the food security issues of high detection rate of E. coli of Chineseaquatic products, we chose Pneumatophorus japonicus as the main object to research on thegrowth law of Escherichia coli in Pneumatophorus japonicus at different temperature toestablish the primary and secondary model of E.coli. Then in order to suppress the E.coli,12kinds of Chinese herbal medicines were used as antimicrobials in laboratory media. Wecomparative analyses of the decolorization of Chinese herbal extract using activated carbon,macroporous resin AB-8and neutral alumina to solve the problem that the color of theChinese herbal medicine extract is dull. To enhance the antibacterial effect, the Chineseherbal extract which was decolorzated was mixed with stabilized chlorine dioxide andNisin respectively and the complex biological preservative will be using in aquaticprocessing. The results showed that:（1）Gompertz model was apply to fit it best at8℃, the correlation coefficient andstandard error were0.9835,0.3108;the Logistic model’s fitting degree was the highest at12and16℃, the correlation coefficient were0.9932、0.9858and the standard error were0.3190、0.5506. The secondary growth model of E. coli in Pneumatophorus japonicus wasdescribed by the square root model,(U_{m a x})^1/2=0.0241T-0.0895，Tmin=3.71℃，R²=0.9966.Validation of the models showed that the residual difference of predicted andobserved value was within±0.01,and the value of bias factor and accuracy factor were0.986and1.016,the predictive models are highly reliable. There is a certain link betweenthe primary model of E.coli and the LDA analysis of electronic nose.（2）The results showed that the antibacterial activities from the Folium Artemisiae,Paeonol and Fructus mume were the highest. Comprehensive consideration of safety,practicality, we chose Fructus mume as the botanical inhibitor of E.coli.（3）The decolorization efficiency of macroporous resinAB-8with its velocity of flow2³BV/h was much better than others, the decolorizating rate come to98.32%when theantibacterial activity material reserved rate was94.5%. Observation under scanningelectron microscope revealed that structure of E. coli cells were significantly destroyed by Fructus mume extract and the cell wall were melted and the morphology of Staphyloccocusaureus almost no change, the inhibition mechanism still needs further study.（4）We got the complex biological preservative to precast aquatic products andcomplex biological preservative to cooked aquatic products. The composited rate wasFructus mume extract: stabilized chlorine dioxide=700:1and Fructus mume extract:Nisin=80:1respectively. Precast aquatic biological preservatives can effectively reduce theE.coli and other microbial’s quantity in the processing of frozen mackerel fillets, and hadno obvious on the Pneumatophorus japonicus, it can be widely used in the processing ofprecast aquatic.