Phenotypic Characteristics and Fatty Acid Composition of Seeds from Different Herbaceous Peony Species Native to China.

Herbaceous peony has been widely cultivated in China due to its substantial ornamental and medicinal value. In the present study, the phenotypic characteristics, total fatty acid (FA) content, and nine FA compositions of herbaceous peony seeds from 14 populations belonging to six species and one subspecies were determined by normal test and gas chromatography/mass spectrometry (GC/MS). The results showed that the phenotypic characteristics of seeds varied dramatically among species. The concentrations of five major FAs in seed oils were as follows: linoleic acid (173.95-236.51 µg/mg), linolenic acid (227.82-302.71 µg/mg), oleic acid (135.32-208.81 µg/mg), stearic acid (6.52-11.7 µg/mg), and palmitic acid (30.67-47.64 µg/mg). Correlation analysis demonstrated that oleic acid had the highest partial correlation coefficient with total FAs and might be applied to develop a model of phenotypic characteristics. FAs were significantly influenced by the following environmental factors: latitude, elevation, and annual average temperature. Based on the FA levels in the seed oils, clustering analysis divided 14 populations into two clusters. It was found that the average contents of oleic acid, linoleic acid, and total FAs in cluster I (147.16 µg/mg, 200.31 µg/mg, and 671.24 µg/mg, respectively) were significantly lower than those in cluster II (196.65 µg/mg, 220.16 µg/mg, and 741.78 µg/mg, respectively). Cluster I was perfectly consistent with subsect. Foliolatae, while cluster II was in good agreement with subsect. Dissectifoliae. Therefore, the FA composition of wild herbaceous peony seed oil might be used as a chemotaxonomic marker.

Comparative Chemical Profiles of Essential Oils and Hydrolate Extracts from Fresh Flowers of Eight Paeonia suffruticosa Andr. Cultivars from Central China.

Paeonia suffruticosa Andr. is a famous ornamental and aromatic plant with hundreds of cultivars in China. The objective of this work was to investigate comparative chemical profiles of essential oils and hydrolate extracts from eight P. suffruticosa Andr. cultivars from Central China. The percentages of hydrocarbons in hydrolate extracts (≤1.1%) were significantly lower than those in the essential oils (29.8⁻63.7%). The percentages of oxygenated compounds in hydrolate extracts (98.3⁻99.8%) were significantly higher than those in the essential oils (34.8⁻69.6%). Multivariate analyses with hierarchical clusters and principal components further indicated the chemical differences between essential oils and hydrolate extracts. Due to predominance of oxygenated compounds and almost trace level of hydrocarbons, P. suffruticosa Andr. hydrolate extracts could be good alternatives to the essential oils. Moreover, distribution of major oxygenated compounds in hydrolate extracts varied with cultivars. Hydrolate extracts from 'SHT', 'WLPS' and 'BXT' presented chemotypes of methylated phenols (65.0%), 2-phenylethanol (64.4%) and geraniol + citronellol + nerol (59.9%), respectively. Those from five other cultivars presented somewhat mixed chemotypes. These results were further confirmed by quantitative evaluation relative to the major oxygenated compounds. The outcome of this work will promote applications of P. suffruticosa Andr. hydrolate extracts in fragrances and cosmetics.

Complete Chloroplast Genome Sequence and Phylogenetic Analysis of Paeonia ostii.

Paeonia ostii, a common oil-tree peony, is important ornamentally and medicinally. However, there are few studies on the chloroplast genome of Paeonia ostii. We sequenced and analyzed the complete chloroplast genome of P. ostii. The size of the P. ostii chloroplast genome is 152,153 bp, including a large single-copy region (85,373 bp), a small single-copy region (17,054 bp), and a pair of inverted repeats regions (24,863 bp). The P. ostii chloroplast genome encodes 111 genes, including 77 protein-coding genes, four ribosomal RNA genes, and 30 transfer RNA genes. The genome contains forward repeats (22), palindromic repeats (28), and tandem repeats (24). The presence of rich simple-sequence repeat loci in the genome provides opportunities for future population genetics work for breeding new varieties. A phylogenetic analysis showed that P. ostii is more closely related to Paeonia delavayi and Paeonialudlowii than to Paeoniaobovata and Paeoniaveitchii. The results of this study provide an assembly of the whole chloroplast genome of P. ostii, which may be useful for future breeding and further biological discoveries. It will provide a theoretical basis for the improvement of peony yield and the determination of phylogenetic status.

Duplication and Whorl-Specific Down-Regulation of the Obligate AP3-PI Heterodimer Genes Explain the Origin of Paeonia lactiflora Plants with Spontaneous Corolla Mutation.

Herbaceous peony (Paeonia lactiflora) is a globally important ornamental plant. Spontaneous floral mutations occur frequently during cultivation, and are selected as a way to release new cultivars, but the underlying evolutionary developmental genetics remain largely elusive. Here, we investigated a collection of spontaneous corolla mutational plants (SCMPs) whose other floral organs were virtually unaffected. Unlike the corolla in normal plants (NPs) that withered soon after fertilization, the transformed corolla (petals) in SCMPs was greenish and persistent similar to the calyx (sepals). Epidermal cellular morphology of the SCMP corolla was also similar to that of calyx cells, further suggesting a sepaloid corolla in SCMPs. Ten floral MADS-box genes from these Paeonia plants were comparatively characterized with respect to sequence and expression. Codogenic sequence variation of these MADS-box genes was not linked to corolla changes in SCMPs. However, we found that both APETALA3 (AP3) and PISTILLATA (PI) lineages of B-class MADS-box genes were duplicated, and subsequent selective expression alterations of these genes were closely associated with the origin of SCMPs. AP3-PI obligate heterodimerization, essential for organ identity of corolla and stamens, was robustly detected. However, selective down-regulation of these duplicated genes might result in a reduction of this obligate heterodimer concentration in a corolla-specific manner, leading to the sepaloid corolla in SCMPs, thus representing a new sepaloid corolla model taking advantage of gene duplication. Our work suggests that modifying floral MADS-box genes could facilitate the breeding of novel cultivars with distinct floral morphology in ornamental plants, and also provides new insights into the functional evolution of the MADS-box genes in plants.

Association mapping for floral traits in cultivated Paeonia rockii based on SSR markers.

Tree peony (Paeonia Sect. Moutan) is an economically important ornamental plant, but little is known about the genetic architecture of important ornamental traits. To effectively improve ornamental value, we require a better understanding of genetic architecture in the complex traits of the tree peony. Association mapping is a powerful tool for detection of variation associated with traits. Thus, we examined the genetic diversity and the population structure of 462 unrelated cultivated P. rockii individuals, then performed association mapping to identify simple sequence repeat (SSR) markers associated with 12 floral traits. We observed a moderate level of genetic diversity (PIC = 0.459) and low linkage disequilibrium (LD) between markers, demonstrating that the potential value of an LD approach in elucidating the molecular basis of the quantitative variation in this species. An analysis of population structure revealed three subgroups in the association population. Subsequent single-marker association analysis identified 46 significant associations, involving the 11 traits with 37 SSRs. These loci explained a small proportion of the phenotypic variance, ranging from 2.68 to 23.97% (mean 5.50%). We also validated 15 of the 46 associations in a linkage mapping population of 159 individuals. Finally, five associations were further confirmed in the linkage mapping population, involving the four traits with four SSRs. These results can serve as a foundation for further analyses of the genetic architecture of floral traits, and the SSRs associated in this work have potential applications in marker-assisted breeding in tree peony.

Chemometric Classification of Different Tree Peony Species Native to China Based on the Assessment of Major Fatty Acids of Seed Oil and Phenotypic Characteristics of the Seeds.

In the present study, we quantitatively measured five major fatty acids (FA) in seed oil using gas chromatography/mass spectrometry (GC/MS) and examined four phenotypic characteristics of the seeds from 19 populations from nine wild tree peony species native to China. The results showed that the unsaturated FAs contents were dominant, of which α-linolenic acid (ALA), linoleic acid, and oleic acid (OA) contents ranged from 14.84 to 42.54 g/100 g, 7.33 to 19.66 g/100 g, and 15.07 - 35.31 g/100 g crude oil, respectively. The phenotypic seed characteristics, such as thousand seed weight (244.01 - 1772.91 g), seed volume (91.31 - 1000.79 mm3 ), weight rate of kernel and coat (1.29 - 3.62) and oil extraction ratio (20.32 - 34.69%), dramatically varied. Based on the contents of the five FAs, the nine species were classified into two groups. The species belonging to subsection Vaginatae were arranged in cluster I and were characterized by high ALA content. Cluster II, consistent with subsection Delavayanae, had a high OA content. From horizontal and vertical perspectives, the natural distribution areas of these two groups were different, reflecting differences in the FA contents and phenotypic seed characteristics. In conclusion, the FAs composition could be used as a chemotaxonomic marker for tree peony species.

Peptide Nucleic Acid Based Molecular Authentication for Identification of Four Medicinal Paeonia Species Using Melting Array Analysis of the Internal Transcribed Spacer 2 Region.

Accurate taxonomic identification of plant materials in herbal medicines is important for product quality control. The genus Paeonia (Saxifragales) is the source of the herbal preparations Paeoniae Radix (Paeoniae Radix Alba and Paeoniae Radix Rubra) and Moutan Radicis Cotex. However, confusion has arisen regarding their contents due to linguistic and taxonomic ambiguities, similar morphologies and different definitions of Paeoniae Radix in the Korean and Chinese national pharmacopoeias, leading to the distribution of adulterated products. To develop a method for identifying the four Paeonia species used in these medicines, three fluorescently-labeled peptide nucleic acid (PNA) probes were designed against ITS2 sequences containing single nucleotide polymorphisms (SNPs) and used in a real-time PCR melting curve assay. Each of the four Paeonia species was accurately identified using this analysis. The accuracy and analytical stability of the PNA melting curve assay was confirmed using commercially available samples of the four Paeonia species. This assay is a reliable genetic tool to distinguish between different Paeonia-derived herbal medicines and identify the botanical origins of Paeoniae Radix and Moutan Radicis Cortex. This technique may also contribute to quality control and standardization of herbal medicines by providing a reliable authentication tool and preventing the distribution of inauthentic adulterants.

[Research and investigation on original plants of medicinal Moutan].

As a kind of famous ornamental flowers, Moutan, known as "the king of flower", mainly originates from various cultivars of Paeonia suffruticosa. Moutan Cortex, a common traditional Chinese medicine, has a long medicinal history for more than 2 000 years. At present, "Fengdanpi", which is the root bark of P. ostii mainly growing in Tongling, Anhui, is a sort of Dao-di herbs in traditional Chinese medicine. However,various editions of Chinese pharmacopoeia has been stipulating that Moutan Cortex originates from the bark root of P. suffruticosa. Textual researches on germplasm of ornamental and medicinal Moutan provided that, Xi'an, Luoyang, Pengcheng, Bozhou, Heze and some other famous cultivation centers had been formed throughout the history. In addition, medicinal practitioners in Song Dynasty had been fully aware of the medicinal differences between ornamental and wild Moutan, and preferred wild single flowers as medicinal Moutan. Moreover, none of cultivation centers of ornamental Moutan were recorded in producing areas of medicinal Moutan. So far, Fengdan and Dianjiang Moutan in Chongqing are single flowers, which is consistent with the ancient herbal books. Therefore, this paper believes that the medicinal and ornamental Moutan are two different germplasm since ancient times. And we proposethat Chinese pharmacopoeia should record P. ostii and the single-flower varieties of P. suffruticosa as the original plants of Moutan Cortex.

[Growth rings in roots of seven Sect. Paeonia species and its application on identification of Paeoniae Radix Rubra].

The growth years of medicinal materials are closely related to their quality, and "Herb-chronology" has been used to determine the growth years of perennial dicotyledonous plants in recent years. On the basis of conventional paraffin section and freehand section, the anatomical study on roots of seven Sect. Paeonia species and main roots of cultivated Paeonia lactiflora was conducted in this paper. The results showed that, there existed some differences in microstructure of the seven species such as P. lactiflora, P. obovata, P. veitchii, P. mairei, P. anomala, P. sinjiangensis and P. anomala var. intermedia, and this could be used to distinguish different species. In the roots of seven Sect. Paeonia species, distinct growth rings were formed because that the different diameters or density of xylem vessels in the secondary xylem formed clusters and arranged interrupted rings in tangential direction. There were growth rings in the main roots of P. lactiflora cultivated 1-4 years in Siping, Jilin, which were all consistent with their growth years. Due to the similar growth characteristics between wild Sect. Paeonia species and cultivated P. lactiflora, the growth rings can provide a basis for the age identification and lay the foundation for the quality evaluation of Paeoniae Radix Rubra.

Molecular identification and phylogenetic analysis of important medicinal plant species in genus Paeonia based on rDNA-ITS, matK, and rbcL DNA barcode sequences.

This study was performed to identify and analyze the phylogenetic relationship among four herbaceous species of the genus Paeonia, P. lactiflora, P. japonica, P. veitchii, and P. suffruticosa, using DNA barcodes. These four species, which are commonly used in traditional medicine as Paeoniae Radix and Moutan Radicis Cortex, are pharmaceutically defined in different ways in the national pharmacopoeias in Korea, Japan, and China. To authenticate the different species used in these medicines, we evaluated rDNA-internal transcribed spacers (ITS), matK and rbcL regions, which provide information capable of effectively distinguishing each species from one another. Seventeen samples were collected from different geographic regions in Korea and China, and DNA barcode regions were amplified using universal primers. Comparative analyses of these DNA barcode sequences revealed species-specific nucleotide sequences capable of discriminating the four Paeonia species. Among the entire sequences of three barcodes, marker nucleotides were identified at three positions in P. lactiflora, eleven in P. japonica, five in P. veitchii, and 25 in P. suffruticosa. Phylogenetic analyses also revealed four distinct clusters showing homogeneous clades with high resolution at the species level. The results demonstrate that the analysis of these three DNA barcode sequences is a reliable method for identifying the four Paeonia species and can be used to authenticate Paeoniae Radix and Moutan Radicis Cortex at the species level. Furthermore, based on the assessment of amplicon sizes, inter/intra-specific distances, marker nucleotides, and phylogenetic analysis, rDNA-ITS was the most suitable DNA barcode for identification of these species.

[Qualitative and quantitative analysis of major constituents of Paeoniae Radix Alba and Paeoniae Radix Rubra by HPLC-DAD-Q-TOF-MS/MS].

In order to explore the differences of chemical constituents of Paeoniae Radix Alba and Paeoniae Radix Rubra, a qualitative analytical method of liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS/MS) was developed for identification of multi-constituents and an HPLC-DAD analytical method was developed for simultaneously determining 14 major compounds (gallic acid, protocatechuic acid, paeoniflorin sulfonate, protocatechuic aldehyde, methyl gallate, oxypaeoniflorin, catechin, albiflorin, and paeoniflorin, ethyl gallate, benzoic acid, pentagaloylglucose, benzoyl-paeoniflorin, and paeonol) in Paeoniae Radix Alba and Paeoniae Radix Rubra. Q-TOF/MS qualitative analysis was performed under negative ion mode and inferred 38 components of Paeoniae Radix Alba and 30 components of Paeoniae Radix Rubra. HPLC-DAD quantitative method result showed the contents of 8 ingredients were different between Paeoniae Radix Alba and Paeoniae Radix Rubra. The results indicated that the new approach was applicable in qualitative and quantitative quality control of Paeoniae Radix Alba and Paeoniae Radix Rubra.

[Quality classification criteria of Paeonia suffruticosa seeds].

In order to establish the quality classification criteria of Paeonia suffruticosa seeds, thirty-one batches of P. suffruticosa seeds from different provenances were selected. The seed rooting rate, seed germination rate, seed purity, seed viability, 1,000-seed weight and moisture content were determined and analyzed through SPSS 20.0 software. Seed rooting rate, seed germination rate and seed purity were selected as the main index for classification, while 1,000-seed weight, seed viability and moisture content could be used as important references. The seed quality grading of P. suffruticosa was set as three grades. The seed quality of each grade should meet following requirements: For the first grade seeds, seed rooting rate ≥ 80%, seed germination rate ≥ 80%, seed purity ≥ 90%, seed viability ≥ 80%, 1,000-seed weight ≥ 250 g, moisture content, ≤ 10. For the second grade seeds, seed rooting rate ≥ 50%, seed germination rate ≥ 60%, seed purity ≥ 70%, seed viability ≥ 75%, 1,000-seed weight ≥ 225 g, moisture content ≤ 10. For the third grade seeds, seed rooting rate ≥ 20%, seed germination rate ≥ 45%, seed purity ≥ 60%, seed viability ≥ 45%, 1,000-seed weight ≥ 205 g, moisture content ≤ 10. The quality classification criteria of P. suffruticosa seeds have been initially established.

Independent domestications of cultivated tree peonies from different wild peony species.

An understanding of plant domestication history provides insights into general mechanisms of plant adaptation and diversification and can guide breeding programmes that aim to improve cultivated species. Cultivated tree peonies (genus Paeonia L.) are among the most popular ornamental plants in the world; yet, the history of their domestication is still unresolved. Here, we explored whether the domestication in China of historically cultivated peonies, that is, the common and flare cultivated tree peonies, was a single event or whether independent domestications occurred. We used 14 nuclear microsatellite markers and a comprehensive set of 553 tree peonies collected across China, including common tree peonies, flare tree peonies and the wild species or subspecies that are potential contributors to the cultivated tree peonies, that is, Paeonia rockii ssp. rockii, P. rockii ssp. atava, P. jishanensis and P. decomposita. Assignment methods, a principal component analysis and approximate Bayesian computations provided clear evidence for independent domestications of these common tree and flare tree peonies from two distinct and allopatric wild species, P. jishanensis and P. rockii ssp. atava, respectively. This study provides the first example of independent domestications of cultivated trees from distinct species and locations. This work also yields crucial insight into the history of domestication of one of the most popular woody ornamental plants. The cultivated peonies represent an interesting case of parallel and convergent evolution. The information obtained in this study will be valuable both for improving current tree peony breeding strategies and for understanding the mechanisms of domestication, diversification and adaptation in plants.

[Identification of moutan cortex and its adulterants by ITS2 sequence].

To explore a new method to identify Moutan Cortex to guarantee its safe use, internal transcribed spacer 2 (ITS2) sequence was used to identify Moutan Cortex and its adulterants. DNA was extracted and target fragments were amplified. Sequences were analyzed and assembled by CodonCode Aligner V3.7.1. Genetic distances were computed and phylogenetic tree was constructed based on kimura 2-parameter (K2P) model by MEGA 5.0. The length of the 20 ITS2 sequences of Moutan Cortex from nine different places is 227 bp, and no variation site was detected. The maximum inter-specificK2P distance of Moutan Cortex is 0, the minimum intra-specific K2P distance is 0.041, the average intra-specific K2P distance is 0.222. According to NJ analysis, Moutan Cortex from different places can get together as one branch with bootstrap support values 99%, which indicates Moutan Cortex can be easily distinguished from its adulterants. Using ITS2 sequence can accurately identify Moutan Cortex and its adulterants, it is an effective supplementary to traditional identification methods.

Rapid microsatellite development for tree peony and its implications.

BACKGROUND: Microsatellites are ubiquitous in genomes of various organisms. With the realization that they play roles in developmental and physiological processes, rather than exist as 'junk' DNA, microsatellites are receiving increasing attention. Next-generation sequencing allows acquisition of large-scale microsatellite information, and is especially useful for plants without reference genome sequences. RESULTS: In this study, enriched DNA libraries of tree peony, a well-known ornamental woody shrub, were used for high-throughput microsatellite development by 454 GS-FLX Titanium pyrosequencing. We obtained 675,221 reads with an average length of 356 bp. The total size of examined sequences was 240,672,018 bp, from which 237,134 SSRs were identified. Of these sequences, 164,043 contained SSRs, with 27% featuring more than one SSR. Interestingly, a high proportion of SSRs (43%) were present in compound formation. SSRs with repeat motifs of 1-4 bp (mono-, di-, tri-, and tetra-nucleotide repeats) accounted for 99.8% of SSRs. Di-nucleotide repeats were the most abundant. As in most plants, the predominant motif in tree peony was (A/T)n, with (G/C)n less common. The lengths of SSRs were classified into 11 groups. The shortest SSRs (10 bp) represented 1% of the total number, whereas SSRs 21-30 and 101-110 bp long accounted for 26% and 29%, respectively, of all SSRs. Many sequences (42,111) were mapped to CDS (coding domain sequence) regions using Arabidopsis as a reference. GO annotation analysis predicted that CDSs with SSRs performed various functions associated with cellular components, molecular functions, and biological processes. Of 100 validated primer pairs, 24 were selected for polymorphism analysis among 23 genotypes; cluster analysis of the resulting data grouped genotypes according to known relationships, confirming the usefulness of the developed SSR markers. CONCLUSIONS: The results of our large-scale SSR marker development using tree peony are valuable for investigating plant genomic structural evolution and elucidating phenotypic variation in this species during its evolution and artificial selection. The newly identified SSRs should be useful for genetic linkage map construction, QTL mapping, gene location and cloning, and molecular marker-assisted breeding. In addition, the genome-wide marker resources generated in this study should aid genomic studies of tree peony and related species.

Discrimination between genetically identical peony roots from different regions of origin based on 1H-nuclear magnetic resonance spectroscopy-based metabolomics: determination of the geographical origins and estimation of the mixing proportions of blended samples.

Sixty peony root training samples of the same age were collected from various regions in Korea and China, and their genetic diversity was investigated for 23 chloroplast intergenic space regions. All samples were genetically indistinguishable, indicating that the DNA-based techniques employed were not appropriate for determining the samples' regions of origin. In contrast, (1)H-nuclear magnetic resonance ((1)H-NMR) spectroscopy-based metabolomics coupled with multivariate statistical analysis revealed a clear difference between the metabolic profiles of the Korean and Chinese samples. Orthogonal projections on the latent structure-discrimination analysis allowed the identification of potential metabolite markers, including γ-aminobutyric acid, arginine, alanine, paeoniflorin, and albiflorin, that could be useful for classifying the samples' regions of origin. The validity of the discrimination model was tested using the response permutation test and blind prediction test for internal and external validations, respectively. Metabolomic data of 21 blended samples consisting of Korean and Chinese samples mixed at various proportions were also acquired by (1)H-NMR analysis. After data preprocessing which was designed to eliminate uncontrolled deviations in the spectral data between the testing and training sets, a new statistical procedure for estimating the mixing proportions of blended samples was established using the constrained least squares method for the first time. The predictive procedure exhibited relatively good predictability (adjusted R (2) = 0.7669), and thus has the potential to be used in the quality control of peony root by providing correct indications for a sample's geographical origins.

Revealing genetic diversity of tree peonies at micro-evolution level with hyper-variable chloroplast markers and floral traits.

KEY MESSAGE: Highly variable regions of chloroplast genome were found to be useful in the detection of plant genetic diversity at micro-evolution level. Our methodology will improve understanding and conservation of plant diversity. Tree peonies are famous flowers with about 2,000 cultivars in the world, belonging to Paeonia sect. Moutan of the Paeoniaceae. They are traditionally classified based on flower forms and colors. Due to the limited number of DNA and morphological markers, and the existence of synonyms and homonyms, evaluation on genetic diversity of so many cultivars remains a challenge. In most cases, it is difficult and even impossible to discriminate tree peony cultivars when they are not in flower. In this study, single nucleotide polymorphism detected from the hyper-variable regions of chloroplast genome was employed to separate tree peony cultivars into different maternal lineages which can be expressed briefly by a nucleotide molecular formula. Our approach enabled a much higher resolution of cultivar identification and classification that has not been obtained before. The newly developed hyper-variable chloroplast markers, as an independent source of taxonomic characteristics, provided novel evidences and higher resolution ability that are helpful in building an effective classification system for evaluation, conservation, and utilization of the tree peony germplasm resources at cultivar level.

[Analysis of rDNA-ITS sequences and similarity of radix paeoniae].

OBJECTIVE: To establish molecular authentication standards of Radix Paeoniae. METHODS: PCR method was used to determine rDNA-ITS sequences of sample S1 and sample S2 including ITS1, 5.8S, and ITS2. The sequences were analyzed by BLAST and DNAMAN software. rDNA-ITS sequences of Paeonia lactiflora Pall., Paeonia veitchii Lynch. and their counterfeit were analyzed by DNAMAN software. RESULTS: Established three molecular authentication standards on Radix Paeoniae: (1) The genera of samples was determined by the results of BLAST; (2) The species of samples were determined by the similarities; (3) The specific base positions confirmed the species of samples. Based on the sequence alignment and base differences, sample S1 was identified as Paeonia lactiflora Pall., and sample S2 was identified as Paeonia veitchii Lynch. CONCLUSION: This paper can give an effective way of Radix Paeoniae identification. What's more, it gives a good example for other Chinese Medicinal Materia authentication.

Comparative and phylogenetic analyses of the chloroplast genomes of species of Paeoniaceae.

Plants belonging to family Paeoniaceae are not only economically important ornamental plants but also medicinal plants used as an important source of traditional Chinese medicine. Owing to the complex network evolution and polyploidy evolution of this family, its systematics and taxonomy are controversial and require a detailed investigation. In this study, three complete chloroplast genomes of sect. Paeonia, one of the sections of Paeonia, were sequenced and then analysed together with 16 other published chloroplast genomes of Paeoniaceae species. The total lengths of the chloroplast genomes of these species were 152,153-154,405 bp. A total of 82-87 protein-coding genes, 31-40 tRNA genes and 8 rRNA genes were annotated. Bioinformatics analysis revealed 61-74 simple sequence repeats (SSRs) in the chloroplast genomes, most of which have A/T base preference. Codon usage analysis showed that A/U-ending codons were more positive than C/G-ending codons, and a slight bias in codon usage was observed in these species. A comparative analysis of these 19 species of Paeoniaceae was then conducted. Fourteen highly variable regions were selected for species relationship study. Phylogenetic analysis revealed that the species of sect. Paeonia gathered in one branch and then divided into different small branches. P. lactiflora, P. anomala, P. anomala subsp. veitchii and P. mairei clustered together. P. intermedia was related to P. obovata and P. obovata subsp. willmottiae. P. emodi was the sister to all other species in the sect. Paeonia.

A comprehensive study of three species of Paeonia stem and leaf phytochemicals, and their antioxidant activities.

ETHNOPHARMACOLOGICAL RELEVANCE: Paeonia plants have been widely used as traditional Chinese medicinal materials for more than 2,000 years in the treatment of cardiovascular, extravasated blood and female genital diseases; paeoniflorin and paeonol have been implicated as the plants' primary active ingredients. AIM OF THE STUDY: Previous studies have been singularly focused on the chemical constituents and content variation of the Paeonia roots in the advancement of traditional Chinese medicine, with the plants' stems and leaves considered useless. This study aims to explore the chemical constituents, content variation, and antioxidant capacity in Paeonia stems and leaves for the future utilization of traditional Chinese medicine, given that current practices of digging and trade endanger Paeonia in the wild. MATERIALS AND METHODS: Herein, secondary metabolites from the stems and leaves from six developmental stages of the annual growth cycle of Paeonia ostii T. Hong & J. X. Zhang, P. 'Hexie', and P. lactiflora Pall. were qualitatively and quantitatively analyzed via high-performance liquid chromatography with a diode array detector (HPLC-DAD) and high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS). Antioxidant capacity at each stage was also evaluated by various free radical scavenging assays. RESULTS: A total of 24 metabolites were detected and identified, including 5 monoterpene glycosides, 4 tannins, 5 phenols, 9 flavonoids, and paeonol. Excepting paeonol and the phenols, the levels of each metabolite category were significantly higher in the leaves than the stems during all developmental stages. The paeoniflorin content in the P. ostii leaves was the highest during the first developmental stage and higher than the standards of the Chinese Pharmacopoeia, suggesting it to be the optimal harvesting stage for medicinal uses. Notably, the antioxidant capacity of the leaves was significantly greater than in the stems, particularly for the leaves of P. 'Hexie'. CONCLUSION: Our study indicates that the leaves of P. 'Hexie' have the potential to be a worthy medicinal substitute to Paeonia roots due to their high monoterpene glycosides, phenols, and flavonoids as well as their strong antioxidant capacity. Further, this study provides a theoretical basis for the development and utilization of non-root Paeonia plant sections as medicinal plant resources.