A simplex PCR-based approach to trace the pulp adulterant of sweet pumpkin in industrially processed mango juice items by targeting the chloroplast ycf1 gene fragment

Abstract

The phenomenon of incorporating sweet pumpkin pulp into industrially processed mango juice has been observed in various reports from Bangladesh in recent years due to the remarkable resemblance in the matrix and color of both fruits at their matured stage. The increasing prevalence of such incidents has become a growing concern for consumers due to the several potential health implications of sweet pumpkin. However, there is no reliable method available so far for the surveillance of this fraudulent activity. Therefore, the present study highlights a prompt and precise approach for tracing the origin of mango and pumpkin species in commercial mango juices based on a polymerase chain reaction. This approach involves the use of newly designed primer sets that target the chloroplast ycf1 genes and can produce the specific detectable amplicons of 206 and 70 bp from ≥ 10−4 and ≥ 10−3 ng/µl of total DNA for mango and pumpkin, respectively. Analyzing six samples of industrially produced mango juice, only four were traceable to their respective origins, and neither mango nor sweet pumpkin were detected in the two remaining samples. However, the non-reactive samples also did not succeed during performance analysis with a plant-specific universal primer set, indicating that the non-reactive samples may contain target unamplifiable or amplifiable DNA along with PCR inhibitors or non-target DNA without PCR inhibitors. Therefore, based on these consistent findings with the plant-specific universal primer set, the newly designed primer sets can be applied to pumpkin adulterant detection in commercial mango juice items.