Development of loop-mediated isothermal method and comparison with conventional PCR assay for rapid on spot identification of tissue of cattle origin

Recent advancements with loop-mediated isothermal amplification (LAMP) in assessment of the species authenticity with meat and seafood products

Species adulteration or mislabeling with meat and seafood products could negatively affect the fair trade, wildlife conservation, food safety, religion aspect, and even the public health. While PCR-based methods remain the gold standard for assessment of the species authenticity, there is an urgent need for alternative testing platforms that are rapid, accurate, simple, and portable. Owing to its ease of use, low cost, and rapidity, LAMP is becoming increasingly used method in food analysis for detecting species adulteration or mislabeling. In this review, we outline how the features of LAMP have been leveraged for species authentication test with meat and seafood products. Meanwhile, as the trend of LAMP detection is simple, rapid and instrument-free, it is of great necessity to carry out end-point visual detection, and the principles of various end-point colorimetry methods are also reviewed. Moreover, with the aim to enhance the LAMP reaction, different strategies are summarized to either suppress the nonspecific amplification, or to avoid the results of nonspecific amplification. Finally, microfluidic chip is a promising point-of-care method, which has been the subject of a great deal of research directed toward the development of microfluidic platforms-based LAMP systems for the species authenticity with meat and seafood products.

Rapid analysis technologies with chemometrics for food authenticity field: A review

In recent years, the problem of food adulteration has become increasingly rampant, seriously hindering the development of food production, consumption, and management. The common analytical methods used to determine food authenticity present challenges, such as complicated analysis processes and time-consuming procedures, necessitating the development of rapid, efficient analysis technology for food authentication. Spectroscopic techniques, ambient ionization mass spectrometry (AIMS), electronic sensors, and DNA-based technology have gradually been applied for food authentication due to advantages such as rapid analysis and simple operation. This paper summarizes the current research on rapid food authenticity analysis technology from three perspectives, including breeds or species determination, quality fraud detection, and geographical origin identification, and introduces chemometrics method adapted to rapid analysis techniques. It aims to promote the development of rapid analysis technology in the food authenticity field.

Rapid diagnosis of Toxoplasma gondii using loop-mediated isothermal amplification assay in camels and small ruminants

Background

This study was conducted to detect the presence of T. gondii in milk and blood samples using three different assays: enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction (PCR), and loop-mediated isothermal amplification assay (LAMP). Whole blood, serum, and milk samples were collected from goats (n = 156), sheep (n = 261), and camels (n = 108) in different governorates in Egypt from December 2019 to February 2021 and screened by ELISA for anti-Toxoplasma IgG antibodies before DNA extraction. The target T. gondii DNA gene was detected and evaluated using the LAMP assay compared to PCR.

Results

T. gondii antibodies were found in milk and serum samples at the rates of (29.26%) and (36.58%) in camels, (34.18%) and (35.89%) in sheep, and (33.7%) and (36.36%) in goats, respectively. Similar to PCR, the percentages of LAMP tests for the detection of the T. gondii DNA gene in milk and blood samples of camels, sheep, and goats were (4.8, 14.63), (6.83, 7.69), and (7.79, 9.09), respectively. LAMP's sensitivity for detecting T. gondii in milk and blood samples, which was identical to that of PCR, was 100%.

Conclusions

The findings clearly demonstrated that there were no variations in T. gondii detection capabilities in milk and blood samples from various animals using both PCR and LAMP tests. It provides a quick, precise, and sensitive method of detecting T. gondii in a variety of samples that may be used both in the field and in laboratory diagnosis.