Application Of Microbial Fluorescence Photoelectric Diagnostic Instrument In The Diagnosis Of Typical Pathogenic Microorganisms In Aquatic Products

China is a large aquaculture country,the annual output of aquatic products accounts for about one-third of the global output.With the rapid intensification and expansion of aquaculture,the incidence of infectious diseases in aquaculture has increased significantly,causing incalculable economic losses to the aquaculture industry and serious harm to the food safety of aquatic products.Among them,the food-borne diseases caused by microorganisms are the main problems that cause food safety.In this paper,the detection strategy of Pseudomonas aeruginosa and Salmonella typhi was developed based on the microbial fluorescence photoelectric diagnostic instrument.The main research contents are as follows:（1）On the basis of FORBID^TMmicrobial rapid analyzer,the microbial fluorescence photoelectric diagnostic analyzer was successfully optimized.The operation interface of the optimized microbial fluorescence photoelectric diagnostic instrument is simple,with built-in light sources of 365 nm,410 nm and 590 nm,and the relative standard deviation of the light source test is less than 2%,and the linear R²value of the light source is above0.98,indicating that the precision and linearity of these three light sources are good.At the same time,the microbial fluorescence photoelectric diagnostic instrument monitors the growth of 128 samples in real time online through fool operation,realizing the full automatic detection and result report of pathogenic microorganisms,which has a good application prospect in the research and development of pathogenic microbial diagnostic reagents and actual detection.（2）The detection strategy of Pseudomonas aeruginosa based on microbial fluorescence photoelectric diagnostic instrument was successfully developed.By adding thespecificprobeL-alanine-7-amino-4-methylcoumarintrifluoroacetate（H-Ala-AMC-TFA）and inhibitors,the pseudomonas aeruginosa diagnostic reagent was successfully developed.Combined with the microbial fluorescent photoelectric diagnostic instrument,the detection strategy completed the detection of Pseudomonas aeruginosa within 30 h,realizing the detection limit of 10⁰CFU/m L and the detection range of 10⁰-10⁵CFU/m L,and showed good specificity and anti-interference ability when mixing with miscellaneous bacteria such as E.coli.The accuracy of the application in the actual sample detection process is also high.Compared with the traditional national standard plate culture method,the log difference of the number of bacteria is within 0.5.At the same time,the detection strategy simplifies the operation steps,saves the detection time,greatly reduces the dependence on technicians,and has great potential in the actual sample detection application.（3）A detection strategy of Salmonella Typhi based on microbial fluorescence photoelectric diagnostic instrument was successfully developed.Similar to Pseudomonas aeruginosa,the detection strategy of Salmonella typhi combined with microbial fluorescence photoelectric diagnostic instrument can realize the quantitative detection of Salmonella typhi with a concentration between 10⁰CFU/m L and 10⁶CFU/m L with good resistance to bacterial interference ability and specificity,and the detection time is less than40 h.The detection strategy of Salmonella typhi synchronized with the national standard method shows that the detection strategy does not need for complicated preprocessing,saves at least 2 days of detection time and avoids a lot of human and material resources input.Therefore,the development of Salmonella typhi testing strategy has greatly reduced the cost of feed testing in the breeding process and improved the testing efficiency,which is highly likely to be directly applied in related enterprises.