DNA extraction optimization and authentication of Vaccinium berries and their products by high-resolution DNA melting analysis

Abstract

Abstract

Food adulteration has been an issue in the food industry for many decades. The market for natural and healthy products has been expanding and therefore the value of raw ingredients harvested from natural sources has increased, and, in some cases, it has led to adulteration of such high-valued products. Berry fruits and products from different species of the genus Vaccinium have been gaining worldwide popularity because of their nutraceutical benefits. However, there are increasing reports of adulteration or misidentification of high-value wild berries with their cultivated counterparts. During recent years, DNA-based methods for the authentication of commercial products have gained popularity, especially regarding species identification. Based on the availability of their chloroplast genome information, we developed DNA markers to differentiate lingonberry from cranberry as well as to discriminate European bilberry from North American blueberry. By using Bar-HRM analysis (DNA barcoding combined with High Resolution Melting), the markers were tested on plant DNA as well as DNA extracted from diverse berry products. The developed markers were able to discriminate between species and, moreover, detect potential adulteration in products made from these berry species. Subsequently, the Bar-HRM result was verified by amplicon sequencing. To conclude, the developed molecular markers represent a valuable tool for the berry food industry.