2D), and the melting temperature of selleck chemicals the amplicon was 83.12 °C. These results indicate

that Lhcb2-1F/1R is highly specific for peach in both qualitative and quantitative PCR in the tested species. An ideal endogenous reference gene should not exhibit allelic variation and should have a consistent copy number among different peach varieties. To test whether different peach cultivars show any sort of allelic variation within the Lhcb2 sequence that we used as the template, we performed conventional PCR and real-time PCR on a fixed amount of DNA from the 4 different peach varieties mentioned above. PCR products of identical size and relative intensity were obtained for all varieties in conventional PCR ( Fig. 2C line 1–4). This result indicates that there were no major sequence differences in this amplified region among the different varieties. Likewise, real-time PCR analysis performed with DNA extracted from these peach varieties exhibited similar melting curves ( Fig. 2D line1–4). These results indicated that the copy number of the Lhcb2 gene was similar

and did not exhibit allelic variation among these peach varieties. To test the sensitivity of the qualitative PCR, a series of PCR test assays were carried out using serial dilutions of genomic DNA ranging from 100 ng to 1 pg. Conventional PCR allowed the detection of the DNA P-gp inhibitor samples containing as little as 0.1 ng (Fig. 3A). The average weight of the peach genome is 0.55 pg per haploid genome; thus, the sensitivity of qualitative PCR is an average of 181 copies of peach genomic DNA. For the Taqman real-time PCR assays in serial dilutions of genomic DNA ranging from 50 ng to 0.5 pg, the detection limit was 5 pg DNA (Fig. 3B), or 9 copies. The Lhcb2 gene copy number analysis was performed by Southern Blot. The genomic DNA of honey peach and flat peach were digested with EcoRI and HindIII, and then hybridized with the DIG-labeled Nintedanib (BIBF 1120) probe (Lhcb2-2F/2R). Only one band was observed in the EcoRI- and HindIII-digested DNA ( Fig. 4). This result indicated that

the Lhcb2 gene is present as a single copy in the peach genome. To ensure the feasibility of the practical application of the Lhcb2 gene, we used the Lhcb2 gene-based qualitative real-time PCR system to detect the presence of peach material in single and mixed fruit juices. We chose to use the nectarine as a positive control and tested the Nongfu orchard fruit and vegetable juice (orange, carrot, apple, pineapple and kiwi fruit), Tropicana juice (grape, pomegranate, peach and apple), and Huiyuan compounded fruit blend (orange, peach, pear, and hawthorn). We were able to amplify the Lhcb2-1F/1R product from the DNA preparations extracted from two samples (two repeats) in qualitative PCR ( Fig. 5A). The results of real-time PCR ( Fig. 5B) were consistent with those of the qualitative PCR.