Validation of the Detection Kit for Pathogenic Bacteria Salmonella typhi Causes Food Poisoning with Real Time Polymerase Chain Reaction

¹ Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Negeri Jakarta, 13220, Indonesia
² Research Center for Detection of Pathogenic Bacteria, Universitas Negeri Jakarta, 13220, Indonesia
³ Department of Biology, Faculty of Mathematics and Natural Science, Universitas Negeri Jakarta, 13220, Indonesia
⁴ Center for Agricultural Quarantine Standards Test, Jl. Pemuda Rawamangun, Jakarta Timur, 13220, Indonesia
⁵ Center Forensic Laboratory of the Criminal Investigation, Police of the Republic of Indonesia, Bogor, 16810, Indonesia
⁶ Institute of Bioproduct Development (IBD), Universiti Teknologi Malaysia (UTM), Skudai, Johor Bahru, Joho, Malaysia
⁷ School of Chemical and Energy Engineering, Universiti Teknologi Malaysia (UTM), Skudai, Johor Bahru, Johor, Malaysia
⁸ City of Scientific Research and Technology Applications, New Burg Al Arab, Alexandria, Egypt

^* Corresponding author: muktiningsih@unj.ac.id

Abstract

Salmonella typhi is a gram-negative bacteria that causes food poisoning. Salmonella typhi bacteria can cause typhus, which can produce lipopolysaccharide complex endotoxin, which plays an important role in the pathogenesis oftyphoid fever. Cases of food poisoning are still common and are one of the causes of death and death in Indonesia. In 2019, there were 77 cases of food poisoning in Indonesia. A fast, accurate, and specific detection method is needed to detect poisoning. In previous studies, the optimum conditions and formulas for detecting these bacteria have been obtained using Real Time PCR. The results of previous studies are used as the basis for the development of a prototypedetection kit. In this study, validation was carried out, which aimed to confirm the results of previous studies so that a reproducible and accurate product for the detection of Salmonella typhi bacteria could be obtained. The results of this study showed that fim-C primers for Salmonella typhi were amplified at 95 base pairs (bp) with an annealing temperature of 60ºC and a standard DNA concentration of 50 ng/µL. The results of the Real Time PCR confirmation test of Salmonellatyphi bacteria at a pre-denaturation of 3 minutes with a concentration of 10 pmol obtained the Ct value according to thestandard with previous studies. The Ct value obtained was 13.96 for S. typhi bacteria. Based on the results obtained, it can be conclude that the condition validation stage for pure cultures was successfully carried out by producing consistentand reproducible data.