Nepentheceae, the most prominent carnivorous family in the Caryophyllales order, comprises the Nepenthes genus, which has modified leaf trap characteristics. Although most Nepenthes species have unique morphologies, their vegetative stages are identical, making identification based on morphology difficult. DNA barcoding is seen as a potential tool for plant identification, with small DNA segments amplified for species identification. In this study, three barcode loci; ribulose-bisphosphate carboxylase (rbcL), intergenic spacer 1 (ITS1) and intergenic spacer 2 (ITS2) and the usefulness of the ITS1 and ITS2 secondary structure for the molecular identification of Nepenthes species were investigated. An analysis of barcodes was conducted using BLASTn, pairwise genetic distance and diversity, followed by secondary structure prediction. The findings reveal that PCR and sequencing were both 100% successful. The present study showed the successful amplification of all targeted DNA barcodes at different sizes. Among the three barcodes, rbcL was the least efficient as a DNA barcode compared to ITS1 and ITS2. The ITS1 nucleotide analysis revealed that the ITS1 barcode had more variations compared to ITS2. The mean genetic distance (K2P) between them was higher for interspecies compared to intraspecies. The results showed that the DNA barcoding gap existed among Nepenthes species, and differences in the secondary structure distinguish the Nepenthes. The secondary structure generated in this study was found to successfully discriminate between the Nepenthes species, leading to enhanced resolutions.

Demand for herbal products has increased because of their purported health benefits and economic value. However, they are susceptible to adulteration, making accurate identification of herbal origin essential, especially for quality control. In recent decades, DNA-based methods have played a crucial role in the development of authentication tools that required good quality of DNA. The manufacturing process of herbal products involved heating, grinding or other mechanical procedures, and addition of excipients/additives caused DNA to degrade which in turn influenced DNA quality. In this study, nine different conventional methods with some modifications were evaluated to determine the best technique producing good quality DNA from capsule herbal products. Assessment was conducted using spectrophotometric measurements and agarose gel electrophoresis. To determine the quality of gDNA, amplification of ITS2 amplicon was performed by PCR. The DNA extraction finding showed that DNA quality from each method resulted in a different DNA purity and yield, hence the ITS2 amplification. Each of the modified DNA extraction methods performed has its own strengths and limitations when it comes to obtaining high quality gDNA. In addition, the study demonstrated the success of ITS2 amplification with the modified DNA extraction methods used.