食品中金黄色葡萄球菌核酸层析检测技术的研究

摘要

核酸层析检测技术是将 PCR 与免疫层析技术相结合，用于食品中金黄色葡萄球菌的快速检测。该技术根据金黄色葡萄球菌 nuc 基因序列，设计特异性的引物，分别标记生物素和异硫氰酸荧光素（FITC），用胶体金免疫层析技术进行检测。通过12株金黄色葡萄球菌及26株常见致病菌的检测结果说明其特异性强，检测灵敏度达到5×103 cfu/mL，样品检测限达到0.5 cfu /g，与传统方法（GB/T 4789.10-2010）结果相比较，无显著性差异（x2=0， P>0.05），可以应用于食品中金黄色葡萄球菌的快速检测与鉴定。%To establish Nucleic Acid Lateral Flow method,based on PCR with Immunochromatographic test strip,for the rapid detection of Staphylococcus aureus in food. According to the sequence of the nuc gene,which encodes the therm ostable nuclease(T Nase)of S.aureus,a pair of oligonucleotide primers which are special to the sequence of nuc gene were designed and synthesized. The PCR amplification product was detected and identified by colloid gold immunochromatographic test. Specificity is tested against four-type strains,eight isolates of S.aureus and other twenty six non- S.aureus species.The detection sensitivity is 5 ×103 cfu/mL in pure culture,detection limit of artificially contaminated samples is 0.5 cfu /g food after enrichment. And there is no observed difference (x2=0, P>0.05) when compared with classical microbiological detection method(GB/T 4789.10-2010). This article demonstrates that nucleic acid lateral flow method is easy,rapid,efficient and may has applications for the detection of S.aureus from different foods.