Detection of Staphylococcus aureus in Dairy Food by Loop-mediated Isothermal Amplification

[Objective] This study was to investigate the creditability of applying loop-mediated isothermal amplification method( LAMP) to detect Staphylococcus aureus in dairy products. [Methods]The primers for heat resistant nuclease gene( nuc) of Staphylococcus aureus were designed for establishing the LAMP method for rapidly detecting Staphylococcus aureus. [Results] The results of LAMP detection on Staphylococcus aureus in various dairy products were completely identical with that by bacterial isolation test; meanwhile it has a high specificity and a 10-fold sensitivity over the hemi-nested PCR. [Conclusion] LAMP can be used for the detection of Staphylococcus aureus in dairy products.

Synchronously Detecting Allergenic Ingredients of Peanut and Sesame in Food by Real-time Fluorescent PCR

Peanut,sesame and other raw materials of food are allergens for special populations.In this study,specific primers and TaqMan probes labeled by different fluorescences were designed targeting Ara h 2 gene of peanut and Ses i 1 gene of sesame.After the optimization of reaction conditions,a real-time fluorescent PCR method was established for simultaneous detection of allergenic ingredients of peanut and sesame in food.Genomic DNA samples of peanut,sesame,rice,wheat,barley,soybean,celery,maize,potato,tomato,walnut,groundnut in shell,cashew nut,sunflower seed,almond,apple,pear and strawberry,pork,beef,mutton and fish were used as templates for PCR amplification with deionized water as negative control template.Results indicated that the established real-time fluorescent PCR method could specifically identify allergenic ingredients of peanut and sesame simultaneously.Sensitivity test showed that the minimum detection limit of this method was 0.01%.Therefore,the established real-time fluorescent PCR method is a specific,sensitive and effective assay for simultaneously detecting allergenic ingredients of peanut and sesame in food.