ABSTRACT
The key factors for producing the best quality Chinese herbal medicines are high-quality germplasm, suitable cultivation area and the proper processing methods for herbal raw materials. Gentiana crassicaulis in Gentiana (Sect. Cruciata), Gentianaceae is one of the original plants of the Chinese herb Qinjiao (Gentianae Macrophyllae Radix), and its type specimen was collected in Lijiang, Yunnan. There is a long planting history of the herb in this area. In this study a sampling plot was designated in these traditional planting areas. G. crassicaulis was planted and herbal raw materials were harvested from the plot. The raw materials were prepared locally and at a pharmaceutical factory in Shanghai using processing methods such as "sweating" or "no sweating", "slicing" or "no slicing" (whole root), and "stoving" or "no stoving" (air drying). The quality of all processed samples was evaluated. In addition, molecular markers were determined for identifying cultivated and wild samples from Lijiang, Yunnan. The results are as follows: ① Samples from the sampling plot and the field are taxonomically identified as Gentiana crassicaulis. ② A total of 270 sequences of trnC-GCA-petN, atpB-rbcL, psbN, ndhB-rps7 and ycf1 were obtained, and three genotypes were determined from the cultivated samples; the type III was shared by both cultivated and wild plants. Based on the molecular markers, a DNA barcoding method to identify cultivated and wild samples of G. crassicaulis from Lijiang, Yunnan was established. ③ Total content of loganic acid and gentiopicroside in all samples was ≥ 2.5%, and above the Chinese Pharmacopoeia (2020) limit. ④ In HPLC fingerprinting, 9 common peaks were assigned and similarity between all samples was > 0.999; and ⑤ In a PCA score plot all slice samples were clustered, while whole root samples were scattered. Therefore, our studies could provide basic data for optimizing the processing method, producing best quality Gentianae Macrophyllae Radix, and evaluating the quality of different ecotype varieties and the multiple origin of herbal medicines.
ABSTRACT
Aa a characteristic medicinal plant in China, Gentiana rigescens Franch. has the function of protecting the liver and invigorating the spleen. At present, there are a few studies on the content determination method of characteristic components of G. rigescens, so it is necessary to establish a scientific and effective quality control method; In this study, The high performance liquid chromatography (HPLC) fingerprint of G. rigescens was established, based on literature reviewed and characteristic spectrum identified, the source range of G. rigescens quality marker (Q-marker) was screened. The effectiveness of the ingredients and the corresponding targets and pathways was analyzed through network pharmacology, and drew the diagram of ''component-target-pathway''. Qualitative and quantitative analysis of G. rigescens was performed by HPLC, and screen the main marker components leading to the differences between groups which were determined the Q-marker of G. rigescens; The literature and HPLC had determined that five iridoids were the main source of G. rigescens Q-marker. The network pharmacology (effectiveness) and qualitative and quantitative (detectability) analysis of G. rigescens from different producing areas confirmed that gentiopicroside, swertiamarin, and sweroside can be used as the main landmark components, and there were significant differences in their contents among different producing areas; The analysis of G. rigescens from different producing areas was carried out by network pharmacology and chemical fingerprints, it is confirmed can be used as potential Q-marker to provide sufficient theoretical basis for the quality control of G. rigescens in the later period.
ABSTRACT
italic>Gentiana crassicaulis Duthie ex Burk. is one of the plant sources of Gentianae Macrophyllae Radix (QinJiao). Gentiana tibetica King ex Hook. f. and Gentiana robusta King ex Hook. f. are relative species of G. crassicaulis. Due to the large intraspecific morphological variation, G. crassicaulis showed high morphological similarity with G. tibetica and G. robusta. And the distribution area of the three species overlaps to some extent, which makes it difficult to identify them. On the basis of morphological identification, the method of molecular identification of the three species was constructed in this study based on chloroplast genomes. The chloroplast genome of Gentiana tibetica is 148 765bp long, with LSC, SSC and IR 81 163 bp, 17 070 bp and 25 266 bp, respectively. The structure of the three is consistent. The chloroplast genome sequences of G. tibetica and G. crassicaulis are highly similar, and the number of variable sites is 9 (149 267 bp in total). Diagnostic SNP that could effectively identify the three species was screened and verified, and a dual-peak SNP detection method was established for the effective identification of each species and mixed samples. Our study provides basic data for the molecular identification of G. crassicaulis and its related species, and the arrangement of related Tibetan medicine.
ABSTRACT
italic>Gentiana crassicaulis Duthie ex Burk. in Gentiana (Sect. Cruciata), Gentianaceae, is one of the original plants of both Gentianae Macrophyllae Radix and Tibetan herb Jie-Ji Na-Bao, which contain such bioactive iridoids as gentiopicroside, loganic acid and others. In this study, based on previous work, the transcriptome of G. crassicaulis was sequenced and analyzed to construct transcriptome databases of roots, stems, leaves and flowers. qRT-PCR verification was conducted for parts of unigenes that may be key enzymes in the pathway of iridoid biosynthesis. The results are as follows: ① a total of 159 534 unigenes were obtained, with an average length of 679 bp. According to the functional classification of GO, unigenes can be divided into 3 categories with 67 branches. The unigenes were aligned in the KOG database and were classified into 25 categories according to function. ② In the KEGG database, 215 unigenes were implicated in 20 standard secondary metabolism pathways. The analysis shows that 305 unigenes encoded 28 key enzymes in the pathway of iridoid biosynthesis, and their expression in different organs is different; and ③ qRT-PCR was approximately consistent with RNA-Seq results. The 7 annotated unigenes identified in this study, HMGS, DXS, MCS, GPPS, G10H, 7-DLNGT and STR, all had higher relative expression levels in the above-ground parts (stem, leaf and flower) than in the underground part (root). Iridoids are common active and index components of such traditional Chinese medicines as Qinjiao, Longdan, Dangyao, and Qingyedan, among others. Therefore, this work provides basic scientific data for further development including obtaining active components or intermediates through biotechnology, exploring the accumulation of effective components, evaluating the quality of different ecotype varieties, and identifying authentic biosynthesis pathways of medicinal materials.
ABSTRACT
As two original plants of Tibetan herb Jieji, Gentiana waltonii Burk. and Gentiana lhassica Burk. belong to Section Cruciata of Gentiana, Gentianaceae. Here, we report on whole chloroplast genome sequences in the alpine species, respectively, and the features of plastomes were investigated. The plastome of G. waltonii is 148 705 bp long (148 652 bp in G. lhassica) and encodes 112 genes, including 78 protein-coding genes, 30 transfer RNA genes, and 4 ribosomal RNA genes. Two pseudogenes, namely ψrps16 and ψinfA, were found in plastomes. In addition, two novel loci were detected, and a species-specific polymerase chain reaction assay was developed for differentiating G. waltonii and G. lhassica from 10 alpine species in Section Cruciata. Gentiana. Our study provides basic data for identifying Tibetan herbs, alpine species conservation and molecular phylogenetic studies of Gentiana and Gentianaceae.
ABSTRACT
Jieji Nabao is a common Tibetan herb. According to our ethnobotanical studies, one of its original plants is identified as Gentiana crassicaulis Duthie ex Burk. (Gentianaceae). Endemic to the Qinghai-Tibet Plateau, this medicinal alpine plant is a threatened species. In this study, 163 individuals from 20 populations of G. crassicaulis were collected throughout its geographical range and amplified fragment length polymorphism (AFLP) was used to investigate genetic variation in this species. A cluster analysis was performed on the AFLP data with Halenia elliptica and Gentiana straminea as the outgroups. From 64 pairs of AFLP primer combinations, 12 pairs were selected for amplification and a total of 315 bands were amplified, of which 254 bands were polymorphic, accounting for 80.63%. High genetic differentiation was detected between populations (87%), and low within populations (13%). The UPGMA (unweighted pair-group method with arithmetic means) tree was topologically consistent with the traditional taxonomic treatments at the species level, and the populations of G. crassicaulis were divided into two branches: one from Yunnan and Guizhou, the other from Tibet, Qinghai, Sichuan and Gansu. PCA analysis and the Mantel test showed that there was a positive correlation between genetic distance and geographical distance. In addition, combined with SSR and SNP markers within cpDNA, the genetic differentiation within the Sichuan population S1 was validated.
ABSTRACT
The roots and flowers of Gentiana waltonii and Gentiana robusta are used as Tibetan herb Jie-Ji in traditional Tibetan medicine, with iridoids as the main active ingredient and index components. To study the pathway of iridoid biosynthesis, roots, stems, leaves and flowers of G. waltonii and G. robusta were subjected to a high-throughput transcriptomic sequencing analysis by Illumina HiseqXTen. After removing insignificant reads and de novo splicing, 79 455 and 78 466 unigenes were obtained from G. waltonii and G. robusta respectively, with average length as 834 bp and 862 bp. The unigene GO functions could be divided into three categories of 65 branches. The unigenes were aligned in KOG database and were classified into 25 classes according to function. In KEGG database, 315 and 340 unigenes of G. waltonii and G. robusta were implicated in 20 standard secondary metabolic pathways, respectively. Furthermore, 80 and 57 unigenes of the two species were analyzed to encode 24 key enzymes in the pathway related to iridoid biosynthesis. There were differences in gene expression among different organs. Based on sequence data, significant amounts of SSRs, SNPs and InDels were detected in each dataset. This study provides a platform for further development of molecular markers, excavation of functional genes, and research into metabolic pathways and their regulatory mechanism within G. waltonii and G. robusta.
ABSTRACT
italic>Gentiana section Cruciata (Gentianaceae) is a medicinally important section of herbs, including Chinese traditional medicine Gentianae Macrophyllae Radix and Tibetan herb Jieji. Here, we assess the taxonomic significance using mtDNA nad1/b-c and nad5/d-e sequence data. A total of 144 nad1/b-c and nad5/d-e sequences from 11 species within Gentianaceae were obtained, including 138 sequences from 10 species within Gentiana section Cruciata and 6 sequences from Halenia elliptica (outgroup). The results showed that mtDNA nad1/b-c has species- level resolution within the section of Cruciata, i.e. the variable in the position 45 “C” could be used as a stable marker locus to distinguish G. robusta from other taxa; the variable in the position 352 and 353 “GA” could distinguish G. crassicaulis and G. tibetica from other taxa within the section. Intraspecies genotype variability was detected in nad1/b-c sequences of G. officinalis and G. siphonantha, respectively. These genotypes could be used as potential DNA barcode. In addition, intraspecies genotype variability was detected in nad5/d-e sequences of G. macrophylla, G. officinalis and G. siphonantha, respectively. Based on the stable marker locus, a species-specific PCR protocol was developed using the primer PF to identifying G. robusta in the section. This study could expand the understanding of the diversity of mtDNA nad1/b-c and nad5/d-e in the genus Gentiana, and provide the essence for the species identification within Gentiana section Cruciata.