Shark fin is a delicacy in many Asian countries. Overexploitation of sharks for shark fin trading has led to a drastic reduction in shark population. To monitor international trade of shark fin products and protect the endangered species from further population decline, we present rapid, user-friendly and sensitive diagnostic loop-mediated isothermal amplification (LAMP) and effective polymerase chain reaction (PCR) assays for all twelve CITES-listed shark species. Species-specific LAMP and PCR primers were designed based on cytochrome oxidase I (COI) and NADH2 regions. Our LAMP and PCR assays have been tested on 291 samples from 93 shark and related species. Target shark species could be differentiated from non-target species within three hours from DNA extraction to LAMP assay. The LAMP assay reported here is a simple and robust solution for on-site detection of CITES-listed shark species with shark fin products.

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Molecular herbal authentication has gained worldwide popularity in the past decade. DNA-based methods, including DNA barcoding and species-specific amplification, have been adopted for herbal identification by various pharmacopoeias. Development of next-generating sequencing (NGS) drastically increased the throughput of sequencing process and has sped up sequence collection and assembly of organelle genomes, making more and more reference sequences/genomes available. NGS allows simultaneous sequencing of multiple reads, opening up the opportunity of identifying multiple species from one sample in one go. Two major experimental approaches have been applied in recent publications of identification of herbal products by NGS, the PCR-dependent DNA metabarcoding and PCR-free genome skimming/shotgun metagenomics. This review provides a brief introduction of the use of DNA metabarcoding and genome skimming/shotgun metagenomics in authentication of herbal products and discusses some important considerations in experimental design for botanical identification by NGS, with a specific focus on quality control, reference sequence database and different taxon assignment programs. The potential of quantification or abundance estimation by NGS is discussed and new scientific findings that could potentially interfere with accurate taxon assignment and/or quantification is presented.

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Dalbergia L.f. is a pantropical genus consisting of 269 species of trees, shrubs, and woody lianas. This genus is listed in CITES Appendices because of illegal logging and trafficking driven by the high economic value of its heartwood. Some species are also used medicinally. Species identification of Dalbergia timber and herbs is challenging but essential for CITES implementation. Molecular methods had been developed for some timber species, mostly from Madagascar and Southeast Asia, but medicinal species in south China were usually not included in those studies. Here, we sequenced and assembled the chloroplast genomes of five Dalbergia species native to Hong Kong, four of which are medicinal plants. Our aim is to find potential genetic markers for the identification of medicinal Dalbergia species based on divergence hotspots detected in chloroplast genomes after comparative and phylogenetic analysis. Dalbergia chloroplast genomes displayed the typical quadripartite structure, with the 50 kb inversion found in most Papilionoideae lineages. Their sizes and gene content are well conserved. Phylogenetic tree of Dalbergia chloroplast genomes showed an overall topology similar to that of ITS sequences. Four divergence hotspots (trnL(UAA)-trnT(UGU), ndhG-ndhI, ycf1a and ycf1b) were identified and candidate markers for identification of several Dalbergia species were suggested.