Short Communication: Detection of Salmonella typhimurium ATCC 14028 and Listeria monocytogenes ATCC 7644 in processed meat products using Real-Time PCR Multiplex Method

Abstract

Abstract. Sophian A, Purwaningsih R, Igirisa RPJ, Amirullah ML, Lukita BL, Fitri RA. 2020. Short Communication: Detection of Salmonella typhimurium ATCC 14028 and Listeria monocytogenes ATCC 7644 in processed meat products using Real-Time PCR Multiplex Method. Asian J Nad Prod Biochem 21: 17-20. The detection of Salmonella typhimurium ATCC 14028 and Listeria monocytogenes ATCC 7644 in processed meat products was carried out using Multiplex Real-Time PCR (qPCR) in the Microbiology and Molecular Biology Laboratory at the Indonesian Food and Drug Authority in Gorontalo. The purpose of this study was to provide alternative testing methods for food products circulating in the market. The sample consisted of 25 samples of processed meat products spike with Salmonella typhimurium ATCC 14028 phase 2 and Listeria monocytogenes ATCC 7644 phase 2. The method used in the study was qPCR analysis using the SYBR Green method, while DNA isolation used the direct PCR method. Data analysis was carried out based on Cycle threshold and Melting temperature based on two main criteria. Cycle threshold (Ct) analysis determines the Ct value of the sample and comparing it with the control. Melting temperature (Tm) analysis determines the temperature at which 50% of double-stranded DNA changed to a single standard and comparing it with the melting temperature of positive control. The results showed Salmonella typhimurium ATCC 14028 in the processed meat was detected at an average Ct value of 10.34, and a Tm value of 85.70. The presence of Listeria monocytogenes ATCC 7644 in the samples was recognized at an average Ct value of 14.04, and an average Tm value of 80.07. It can be concluded that the real-time multiplex PCR method can be used to detect Salmonella typhimurium ATCC 14028 and Listeria monocytogenes ATCC 7644 by using the melting curve (Tm) analysis.