Traditional species identification has gone through five stages -- morphology, cytology, biochemistry, immunology and molecular biology. At present, the use of DNA technology for species identification has become a research hotspot. In the use of DNA for species identification, the presentation and application of DNA barcode is of epoch-making significance. With the successful application of new technology in species identification, forensic species identification has also made corresponding development, and is expected to play an important role in forensic related fields. This paper briefly describes the general situation and principles of DNA barcode technology as well as its advantages and limitations when applied to biological classification, and discusses the future significance and feasibility of DNA barcode technology in forensic applications, in order to provide new ideas for future forensic identification.
DNA/genetics* ; DNA Barcoding, Taxonomic ; Forensic Medicine

The use of animal medicine has a long history in China, it has the characteristics of high curative effect,strong activity, wide application and great potential. However,the circulation of animal medicine in current market mixed counterfeit variety and complex. Molecular identification technology of DNA barcoding is an emerging molecular biotechnology in recent years, it is a powerful supplement to traditional identification methods. This method can well identify animal species at the molecular level and has high accuracy, it can identify animal medicines quickly and monitor the medicine market effectively. This article summarizes the research process of molecular identification of DNA barcoding, the application of DNA barcoding in medicinal animals identification in recent years, and the limitations of DNA barcoding technology.
Animals ; China ; DNA ; DNA Barcoding, Taxonomic ; Research

DNA barcoding is an effective technique in species identification. To determine the candidate sequences which can be used as DNA barcode to identify in Papaver genus, five potential sequences (ITS, matK, psbA-trnH, rbcL, trnL-trnF) were screened. 69 sequences were downloaded from Genbank, including 21 ITS sequences, 10 matK sequences, 8 psbA-trnH sequences, 14 rbcL sequences and 16 trnL-trnF sequences. Mega 6.0 was used to analysis the comparison of sequences. By the methods of calculating the distances in intraspecific and interspecific divergences, evaluating DNA barcoding gap and constructing NJ and UPMGA phylogenetic trees. The sequence trnL-trnF performed best. In conclusion, trnL-trnF can be considered as a novel DNA barcode in Papaver genus, other four sequences can be as combination barcode for identification.
DNA Barcoding, Taxonomic ; methods ; Papaver ; classification ; genetics

DNA barcode technology was used to establish a rapid identification method of Chrysanthemum indicum and Ch. morifolium based on psbA-trn H,mat K and trn L sequences. The total DNA was extracted from 21 samples collected,and the psbA-trn H,mat K,trn L sequences were amplified by PCR and sequenced. The information of these sequences were obtained. We aligned all 63 sequences,calculated the intraspecific and interspecific distances,analysed the SNPs distribution of psbA-trn H+mat K+trn L combination sequences and constructed the Neighbor-joining( NJ) Tree,using MEGA 7. 0. The results showed that the genetic distances of Ch. indicum,Ch. indicum( Juhuanao)and Ch. morifolium were overlapped. The SNPs analysis of psbA-trn H+mat K+trn L combination sequences showed that there were 19 nucleotide polymorphism loci( SNPs) and nine parsim-informative sites in the combination sequences. In addition,Ch. indicum showed more obvious sequence polymorphism than those of Ch. indicum( Juhuanao) and Ch. morifolium. The psbA-trn H sequences showed obvious length variation.The NJ Tree showed that Ch. morifolium numbered C2-C5 were clustered into a single subbranch with a bootstrap value of 62%,and Ch.morifolium could be distinguished from Ch. indicum and Ch. indicum( Juhuanao). Moreover,Ch. indicum numbered Z9 and Z10 collected from Gansu province were singly clustered into one branch with a bootstrap value of 77%. It was also found that the changes of psbA-trn H and trn L sequences information of Ch. indicum samples from the northwest were obviously related to the geography and environment. Moreover,Ch.indicum and Ch. indicum( Juhuanao) had obvious differentiation,were also regarded as the evolutionary sources of Ch. morifolium. Therefore,psbA-trn H+mat K+trn L combination sequences as DNA barcode can identify Ch. indicum and Ch. morifolium accurately and rapidly,which provides an important basis for germplasm resources identification and species identification.
Chrysanthemum ; DNA Barcoding, Taxonomic ; DNA, Plant ; Phylogeny ; Trees

The combination of morphological characteristics and DNA barcodes was used to a systematic study of Hippocampus spinosissimus,laying the foundation for rapid and accurate identification for the medical seahorse species. According to the reported literature and observation on seahorse samples,the typical characteristics of the H. spinosissimus include highly developed spiny,much short nose,single or double cheeks and strongly developed spines bordering pouch. Genomic DNAs of H. spinosissimus and other related seahorse species were extracted using the TIANamp Marine Animals DNA Kit. The COⅠ and ATP6 genes were amplified and sequenced in both directions. After the verification by Blast,the GC content,intraspecific and interspecific genetic distance,and the Neighbor joining( NJ) phylogenetic trees were analyzed by MEGA 7. The lengths of the COⅠ and ATP6 genes were 649 bp and 602-603 bp,respectively,with the average GC content of 39. 96% and 35. 37%. The maximum intraspecific genetic distances in H. spinosissimus based on COⅠ and ATP were both far less than the minimum interspecific genetic distance between H. spinosissimus and other seahorses,suggesting a significant barcoding gap. NJ analysis results of COⅠ and ATP6 exhibited that all H. spinosissimus species clustered together,indicating that the two DNA barcode could identify H. spinosissimus from other seahorses accurately and quickly. In addition,H. spinosissimus shared a close genetic relationship between H. kelloggi according to the NJ tree. Furthermore,there exits three stable subgroup structure of H. spinosissimus,indicating that COⅠ and ATP6 barcodes could be applied the indicator for the geographical ecology research of H. spinosissimus. The results obtained the typical morphological and molecular identification characteristics of H. spinosissimus,which played central roles for the development of species identification. This study provides an important basis data for expanding the medical seahorse resources and ensuring the safety of clinical medicine.
Animals ; Base Composition ; DNA ; DNA Barcoding, Taxonomic ; Phylogeny ; Smegmamorpha/genetics*

In order to identify the source of Citrus grandis and evaluate its quality originate from two areas comprehensively,DNA barcode was used to identify 26 samples of C. grandis. The content of naringin,rhoifolin,naringenin and apigenin was determined by UPLC method,and the color difference was numerically studied by color difference analyzer,which was related to the effective components of C. grandis. The results showed that samples was the source of C. grandis in both regions. The ITS2 sequence length was about400-500 bp,and the sequence similarity reached 99. 82%. There was only one base deletion in the two groups. There was one base A in some medicinal materials of Guangdong at 330 bp,but no base in Chongqing. The contents of naringin and rhoifolin in Chongqing samples were higher than those in Guangdong samples,and there were statistical differences between naringenin and apigenin. The chroma value showed that L*value of Guangdong was larger,a*value was smaller,L*value of Chongqing was smaller,and a*value was larger,while the b*value of both was not significantly different; The results of correlation analysis showed that naringin,rhoifolin,naringenin were positively correlated with L*,b*value,negatively correlated with a*value,and apigenin had no correlation with L*,a*,b*value. In this study,the scientific identification and evaluation of C. grandis was carried out to provide a new idea for the further study of the rapid identification and evaluation of C. grandis.
Apigenin ; Citrus/genetics* ; DNA Barcoding, Taxonomic ; Drugs, Chinese Herbal

DNA barcoding has been widely used in species identification and biodiversity research. A short fragment of the mitochondrial cytochrome c oxidase subunit I (COI) sequence serves as a DNA bio-barcode. We collected DNA barcodes, based on COI sequences from 156 species (529 sequences) of fish, insects, and shellfish. We present results on phylogenetic relationships to assess biodiversity the in the Korean peninsula. Average GC% contents of the 68 fish species (46.9%), the 59 shellfish species (38.0%), and the 29 insect species (33.2%) are reported. Using the Kimura 2 parameter in all possible pairwise comparisons, the average interspecific distances were compared with the average intraspecific distances in fish (3.22 vs. 0.41), insects (2.06 vs. 0.25), and shellfish (3.58 vs. 0.14). Our results confirm that distance-based DNA barcoding provides sufficient information to identify and delineate fish, insect, and shellfish species by means of all possible pairwise comparisons. These results also confirm that the development of an effective molecular barcode identification system is possible. All DNA barcode sequences collected from our study will be useful for the interpretation of species-level identification and community-level patterns in fish, insects, and shellfish in Korea, although at the species level, the rate of correct identification in a diversified environment might be low.
Biodiversity ; DNA ; DNA Barcoding, Taxonomic ; DNA, Mitochondrial ; Electron Transport Complex IV ; Insects ; Korea ; Shellfish

Resina Draconis, a rare and precious traditional medicine in China, is known as the "holy medicine for promoting blood circulation". According to the national drug standard, it's derived from the resin extracted from the wood of Dracaena cochinchinensis, a Liliaceae plant. In addition, a variety of Dracaena species all over the world can form red resins, and there is currently no molecular identification method that can efficiently identify the origin of Dracaena medicinal materials. In this study, seven species of Dracaena distributed in China were selected as the research objects. Four commonly used DNA barcodes(ITS2, matK, rbcL and psbA-trnH), and four highly variable regions(trnP-psaJ, psbK-psbI, trnT-trnL, clpP) in chloroplast genome were used to evaluate the identification efficiency of Dracaena species. The results showed that clpP sequence fragment could accurately identify seven species of Dracaena plants. However, due to the long sequence of clpP fragment, there were potential problems in the practical application process. We found that the combined fragment "psbK-psbI+ trnP-psaJ" can also be used for accurate molecular identification of the Resina Draconis origin plants and relative species of Dracaena, which were both relatively short sequences in the combined fragment, showing high success rates of amplification and sequencing. Therefore, the "psbK-psbI+ trnP-psaJ" combined fragment can be used as the DNA barcode fragments for molecular identification of Resina Dracon's origin plants and relative species of Dracaena. Research on the identification of Dracaena species, the results of this study can be used to accurately identify the original material of Resina Draconis, and providing effective means for identification, rational development and application of Resina Draconis base source.
China ; DNA Barcoding, Taxonomic ; DNA, Plant/genetics* ; Dracaena/genetics* ; Plants ; Resins, Plant ; Sequence Analysis, DNA

DNA barcode technology was used to establish a rapid identification method of Chrysanthemum indicum based on ITS2 sequences. The total DNA was extracted from 22 collected samples,and the ITS2 sequence was amplified by PCR and sequenced,and the information of ITS2 sequence was obtained. Another 14 items of the same family or the same genus were downloaded from Gen Bank.We aligned all 36 sequences,calculated the intraspecific and interspecific distances,and constructed Neighbor Joining( NJ) phylogenetic tree,using MEGA 7. 0. The difference of the secondary structure between the ITS2 sequences was compared. The results showed that the genetic distance of Ch. indicum and Ch. morifolium was overlapped,but the maximum intraspecific distance was far less than the minimum interspecific distance between and among Ch. indicum and other species,with an obvious barcoding gap. The NJ tree showed that Ch. indicum and Ch. morifolium shared a clade,and most of Ch. morifolium with some Ch. indicum were shared a subclade,while Inula lineariifolia,Sinosenecio oldhamianus and Senecio scandens belonged to one clade separately. ITS2 secondary structures for I. lineariifolia,S. oldhamianus and S. scandens were significantly different enough to identify completely but Ch. indicum and Ch. morifolium shared two secondary structures of A and B. It was proved that Ch. indicum was one of the evolutionary sources of Ch.morifolium. Therefore ITS2 sequence as DNA barcode can identify Ch. indicum and its adulterants accurately and quickly. The study provides an important basis for Ch. indicum for the identification of germplasm resources and the safety of clinical medication.
Chrysanthemum ; DNA Barcoding, Taxonomic ; DNA, Plant ; DNA, Ribosomal Spacer ; Drugs, Chinese Herbal ; Phylogeny ; Quality Control

By exploring additional phylogenetic information hidden in ITS2 secondary structure,the possibility of identifying Chrysanthemum indicum and its related species with DNA barcode of ITS2 nucleic acid sequence and its structure information were discussed.The genomic DNA was extracted from 12 samples. The ITS2 fragments were amplified by PCR and sequenced bidirectionally to obtain ITS2 sequence information. 28 sequences of related species for Ch. indicum were downloaded from Gen Bank. Until all 40 ITS2 sequences were aligned,ITS2 secondary structure prediction and structure comparison were finished. Then ITS2 secondary structure information was coded. After comparing ITS2 structure information and nucleic acid information,MP phylogenetic trees were built. The results showed that the secondary structures of ITS2 shared the same structure model--a four-fingered hand. They not only have the common characteristics of ITS2 secondary structures in plants,but also have many other conservative sequences,and their overall conservativeness is high. Among all species used in this study,their ITS2 secondary structures had obvious difference. In addition,the number of mutation sites in the joint matrix compared with the nucleic acid sequences increased by nearly 90%,which greatly enriched the number of mutation sites. This method of information analysis distinguished Ch. indicum from its related species. At the same time,the support rate of the branches of evolutionary trees and the identification rate of species were significantly improved. Although there was no distinction between Ch. zawadskii and Ch. morifolium,it effectively distinguished the three species,namely,Ch. hypargyrum,Ch.oreastrum,and Ch. dichrum. Therefore,the authors suggest that the ITS2 sequence combined with its structural data information should be applied to the identification of Ch. indicum and its related species,and be widely applied to DNA barcode research.
Chrysanthemum ; DNA Barcoding, Taxonomic ; DNA, Plant ; DNA, Ribosomal Spacer ; Phylogeny ; Plants