Studies Of Preparation Technology Of Serratia Marcescens And Phage ΦX174 For Quantitative Test

In recent years,with the emergence of high pathogenic avian influenza,Ebola virus,Zika virus and others,we should pay more attention on correspording studies.At the meanwhile,the protective equipment and performance evaluation play a very important role in this aspect.Therefore,it’s necessary to develop the method and standard of simulation of analog bacterial and viruses.This can provide standards for the protective equipment and performance evaluation and provide metrology support for pathogen and bio-safety monitor.The results were as follows:The first chapter showed the importance of the performance evaluation of protective equipment and simulation of analog bacterial viruses with a more comprehensive and systematic introduction,then compared and analyzed the methods for detecting microor-ganisms and their respective characteristics.It was counted by flow cytometry and bacteria-measurement of Serratia marcescens in the second chapter.We use parameter optimization through flow cytometry measure the number of Serratia marcescens,compared with the plate counting method.The results showed that the relationship between the FCM and the plate counting calculation is associated with each other is close and the value of R2 is 0.9989.In the third chapter,simulation of bacteria-In the basis of bacteria-Serratia marcescens standard material through single factor experiments,we determined the protective effect of each factor lyophiliized and screened the factors which have significant influence on PB method,and then used the response surface test to make the significant factors become the best,get the final lyoprotectant formulations.The fourth chapter simulates bacteria-Serratia marcescens added to a composite protective agent,freeze-dried preparation of standard material of mixture into balls,by comparing the lyophilized bacterial count to verify the protection agent before and after effects,and the homogeneity and stability of standard material.Results showed that protection of composite protective agent can arrive at 92.44%,can effectively protect the bacteria during the process of freeze drying,preparation of Serratia marcescens have a good homogeneity,and under conditions that-20 ℃,it can be stored for half a year.The fifth chapter filtered out phage ΦX174 stable and saved under frozen dry environment agent through single factors test,and based on the optimization frozen dry process,simulated virus-phage ΦDX 174 and frozen dry protection agent,made it become cake-like standard material,study composite protection agent on phage ΦX174 standard material frozen powder of protection efficiency and uniform sex,and stability through the method of flat count.Results showed that phage ΦDX174 composite protective agent for protection is up to 95.44%,this can be an effective protection way of phage in the freeze-drying process.The Bacteriophage ΦX174 standard material,forms good water speed,a good uniformity at-20 ℃ which can be good to make it stable for three months.The standard material developed in this article can be used on quality controlling in food testing laboratory.It also can be used in assessment of Staphylococcus aureus and Escherichia coli in foods.