Foodborne pathogens refer to pathogens introduced during food processing and distribution. These pathogens survive, grow, and metabolize in food, causing spoilage and damage. Some pathogens also secrete toxins, directly or indirectly leading to illness in humans.

Common Types of Foodborne Pathogens: Common bacterial food poisoning pathogens include: pathogenic Escherichia coli (especially hemorrhagic Escherichia coli O157:H7), Salmonella, Shigella, pathogenic Vibrio (including Vibrio cholerae and Vibrio parahaemolyticus), Staphylococcus aureus, and its enterotoxins. In recent years, an increasing number of microorganisms have been found to cause bacterial food poisoning, including Listeria monocytogenes and Campylobacter jejuni.

Harmful Effects of Foodborne Pathogens: Under normal circumstances, they often cause acute poisoning. Mild cases often present with symptoms of acute gastroenteritis; however, severe cases can lead to respiratory, circulatory, and neurological symptoms. Some spoiled foods contain low levels of toxic substances, or due to the characteristics of their toxicity, they may not cause acute poisoning. However, long-term consumption can often lead to chronic poisoning, and may even exhibit carcinogenic, teratogenic, or mutagenic effects. Besides causing acute poisoning, consuming rotten, spoiled, or moldy food poses extremely serious potential hazards. It has been found that food safety issues caused by foodborne pathogens do not decrease or disappear with economic development and technological progress. Serious food safety incidents occur frequently worldwide, and foodborne diseases have not been effectively controlled. In recent years, the global incidence of foodborne diseases has shown a continuous upward trend.

Detection Techniques for Foodborne Pathogens: Currently, the main detection techniques for foodborne pathogens include conventional culture methods; rapid detection methods based on DNA detection; hybridization-based detection methods; and immunoassay-based detection methods. Among these, molecular biology detection techniques play a crucial role in the identification and detection of foodborne pathogens due to their high sensitivity, high specificity, speed, simplicity, and time-saving advantages. Methods utilizing molecular biology techniques for detecting foodborne pathogens include multiplex PCR, real-time quantitative PCR, loop-mediated isothermal amplification (LAMP), gene chips, liquid-phase chips, and gene probe technologies.Compared to conventional PCR, LAMP is a novel nucleic acid amplification method with the characteristics of simplicity, speed, and high specificity. This technology can rival or even surpass PCR technology in terms of sensitivity, specificity, simplicity, detection range, and cost. 

LAMP offers the following advantages:

1. High Specificity & Sensitivity: LAMP technology utilizes two pairs of primers (inner and outer primers) to accurately bind to six or more specific regions on the target sequence, resulting in amplification. If any of these six regions does not match the primers, nucleic acid amplification will not occur. Therefore, LAMP detection methods offer significantly higher specificity compared to conventional PCR. To be more specific, LAMP doubles the number of DNA primers, creating “deletion loops.” Traditional PCR assays can identify only two separate regions of the target genetic material. They rely on two primers annealing the separated DNA strands, then replicating and amplifying the target DNA. In contrast, LAMP technology uses four to six primers, recognizing six to eight different regions in the sample DNA. These primers and the Bst polymerase used not only shift the DNA strands but also wrap the ends of the strands together before amplification. This unique circular structure accelerates the reaction rate and allows for exponential accumulation of target DNA, thereby improving the sensitivity of the detection results. LAMP detection sensitivity is 10 to 100 times higher than conventional PCR

2. Fast Detection Speed: Compared to conventional PCR, detection based on LAMP technology offers increased speed of reaction. The basic LAMP reaction can be completed within 60-70 minutes; adding a circular primer can even shorten the reaction time to 30 to 40 minutes.

3. Simplified Operation Steps. Researchers using PCR detection must pre-prepare lysis buffers or mixing reagents and perform additional experimental procedures to extract and purify DNA samples. These steps often introduce the possibility of human error or cross-contamination. On the other hand, LAMP detection kits offer more ready-to-use methods that do not necessarily require buffers or mixing reagents for further sample preparation.

4. Unified Workflow: LAMP can convert multiple detection procedures into a single unified workflow. Researchers in food safety laboratories using PCR detection have historically needed to execute different detection protocols for each pathogen (whether it’s Salmonella, Listeria, Escherichia coli O157:H7, etc.). This can complicate the detection process and significantly increase the probability of errors. Typically, laboratories are resource-constrained and under high workload; maintaining consistency across multiple detection steps can effectively reduce the probability of errors. The advantage of LAMP is that it can use a single unified detection protocol for all pathogens. This enables researchers to use the same familiar procedures to detect all pathogens, and even to detect different pathogens simultaneously in the same procedure, allowing for batch processing of samples.

5. Less Maintenance Labor & Cost. Thermal cycling is the backbone of PCR assays. It involves multiple moving parts or cooling fans, requiring frequent maintenance and cleaning, adding significant costs to the lab. For LAMP, no thermal cycling is required, which makes LAMP instruments virtually unrestricted by any moving parts, allowing for smaller machines, much less maintenance, as well as reduced benchtop space.

6. Less Matrix Inhibitor Impact: For PCR reactions, the temperature cycles not only require longer run times but can also lead to interference from other inhibitory substances. LAMP, on the other hand, performs isothermal DNA amplification within a stable temperature. This continuous amplification is unaffected by sample matrix inhibitors.

For further information, refer to https://redantelopetech.com/product-category/food-environment-test/pathogen-detection-solutions/pathogen-lamp-test/.