Development of DNA-based species-specific real-time PCR markers for four berry fruits and their application in commercial berry fruit foods

Abstract

Berry fruits have attracted attention because of their purported benefits for aging, cardiovascular disease, and cancer. Therefore, highly priced berry fruits might be targets for food adulteration and fraud. In this study, eight speciesspecific primer sets based on the single nucleotide polymorphism of the chloroplast genomes of four berry fruits (aronia, blackberry, cranberry, and strawberry) were developed for quantitative real-time PCR (qPCR) analysis by SYBR Green staining with the aim of preventing berry fruit food fraud. The developed primer pairs exhibited high efficiencies ranging from 88 to 110% with strong correlation coefficients (R 2 > 0.99) for the amplification of each target species. However, no clear correlation coefficients were evident for non-target species. To evaluate the practicality of the developed primers, 18 commercial berry fruit products were verified by qPCR analysis. The developed primer pairs were amplified to a low C t value (range 16.1-23.3) for the target species and proved capable of detecting target species in berry fruit commercial foods. Therefore, the developed qPCR-based species-specific markers could be suitable for the prevention of berry fruit food fraud and to verify marker reliability. which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Development of molecular markers to distinguish between morphologically similar edible plants and poisonous plants using a real‐time PCR assay

“…Alternatively, SYBR Green I, binding to double‐stranded DNA in a sequence independent manner, can provide more a flexible, convenient and inexpensive method compared to probe‐based methods 8,9 . Indeed, many research studies have used SYBR Green based real‐time PCR assays for the detection of ingredients in commercial foods, such as bovine and poultry, Cynanchum wilfordii , Orostachys species and berry fruits 6,10–12 …”

Authentication of berries and berry‐based food products

“…Finally, An et al. (2019) used SNP/indel‐based species‐specific primers in order to authenticate four different berry species, namely, black chokeberry, blackberry, cranberry, and strawberry, in commercial products by qRT‐PCR. The analysis was based on short (94–224 bp) amplicons from the chloroplast matK , rbcL , and trnL‐F regions, often deployed in DNA barcoding.…”

“…By using species-specific primer pairs and PCR products of less than 250 bp, they were able to detect the different species, as well as adulteration in food products, even in mixed juices and after DNA-damaging thermal treatments. Finally, An et al (2019) used SNP/indel-based species-specific primers in order to authenticate four different berry species, namely, black chokeberry, blackberry, cranberry, and strawberry, in commercial products by qRT-PCR. The analysis was based on short (94-224 bp) amplicons from the chloroplast matK, rbcL, and trnL-F regions, often deployed in DNA barcoding.…”

Authentication of holy basil using markers relating to a toxicology-relevant compound

“…The combined trait-independent and trait-related assay could be adapted to be used in real-time PCR. This might allow a more well-defined result than gel visualization, potential for quantification via calibration curve of DNA concentration and Ct values, and assessment of mixture samples by analysing the melting curve [52].…”