Chemical constituents with anti-allergic activity from the root of Edulis Superba, a horticultural cultivar of Paeonia lactiflora

Comprehensive study on genetic and chemical diversity of Asian medicinal plants, aimed at sustainable use and standardization of traditional crude drugs

Our representative studies to achieve sustainable use of crude drugs and ensure their stable quality are introduced: comprehensive studies on genetic, chemical, and sometimes pharmacological diversity of Asian medicinal plants including Paeonia lactiflora, Glycyrrhiza uralensis, Ephedra spp., Saposhnikovia divaricata, and Curcuma spp., as well as their related crude drugs. (1) For peony root, after genetic and chemical diversity analysis of crude drug samples including white and red peony root in China, the value-added resources with quality similar to red peony root were explored among 61 horticultural P. lactiflora varieties, and two varieties were identified. In addition, an optimized post-harvest processing method, which resulted in high contents of the main active components in the produced root, was developed to promote cultivation and production of brand peony root. (2) Alternative resources of glycyrrhiza, ephedra herb and saposhnikovia root and rhizome of Japanese Pharmacopoeia grade were discovered in eastern Mongolia after field investigation and quality assessment comparing Mongolian plants with Chinese crude drugs. Simultaneously, suitable specimens and prospective regions for cultivation were proposed. (3) Because of the wide distribution and morphological similarities of Curcuma species, classification of some species is debated, which leads to confusion in the use of Curcuma crude drugs. Molecular analyses of the intron length polymorphism (ILP) markers in genes encoding diketide-CoA synthase (DCS) and curcumin synthase (CURS) and trnK sequences, combined with essential oils analysis, were demonstrated as useful for standardization of Curcuma crude drugs. The above studies, representing various facets, can be applied to other crude drugs.

Metabolomics analysis of peony root using NMR spectroscopy and impact of the preprocessing method for NMR data in multivariate analysis

Peony root is an important herbal drug used as an antispasmodic analgesic. To evaluate peony roots with different botanical origins, producing areas, and post-harvest processing, 1H NMR-based metabolomics analysis was employed. Five types of monoterpenoids, including albiflorin (4), paeoniflorin (6), and sulfonated paeoniflorin (25), and six other compounds, including 1,2,3,4,6-penta-O-galloyl-β-D-glucose (18), benzoic acid (21), gallic acid (22), and sucrose (26) were detected in the extracts of peony root samples. Among them, compounds 4, 6, 18, and total monoterpenoids including 21 were quantified by quantitative 1H NMR (qHNMR). Compound 25 was detected in 1H NMR spectra of sulfur-fumigated white peony root (WPR) extracts indicating that 1H NMR was a fast and effective method for identifying sulfur-fumigated WPR. The content of 26, the main factor affecting extract yield, increased significantly in peony root after low-temperature storage for one month, whereas that in WPR did not increase due to the boiling treatment after harvesting. We investigated the impact of preprocessing methods to such analysis for NMR data from commercial samples, resulting that the data matrix transformed from qHNMR spectra and normalized to internal standard were optimum for multivariate analysis. The multivariate analysis demonstrated that among commercial samples derived from P. lactiflora, peony root samples in Japanese market (PR) had high contents of 18 and 22, and red peony root (RPR) samples had high content of monoterpenoids represented by 6; and among RPR samples, those derived from P. veitchii showed higher contents of 18 and 22 than those from P. lactiflora. The 1H NMR-based metabolomics method coupled with qHNMR was useful for evaluation of peony root and would be applicable for other crude drugs.

Genus Paeonia: A comprehensive review on traditional uses, phytochemistry, pharmacological activities, clinical application, and toxicology

ETHNOPHARMACOLOGICAL RELEVANCE

Paeonia, which comprises approximately 52 shrubs or herbaceous perennials around the world, is the only genus of the Paeoniaceae and is pervasively distributed in Asia, southern Europe, and North America. Many species of the genus Paeonia have been used for centuries in ethnomedical medical systems.

AIM OF THE REVIEW

The present study aims to summarize the traditional uses, clinical applications, and toxicology of the genus Paeonia, to critically evaluate the state-of-the-art phytochemical and pharmacological studies of this genus published between 2011 and 2020, and to suggest directions for further in-depth research on Paeonia medicinal resources.

MATERIALS AND METHODS

Popular and widely used databases such as PubMed, Scopus, Science Direct, and Google Scholar were searched using the various search strings; from these searches, a number of citations related to the traditional uses, phytochemistry, biological activities, clinical application, and toxicology of the genus Paeonia were retrieved.

RESULTS

The use of 21 species, 2 subspecies, and 7 varieties of the genus Paeonia as traditional herbal remedies has been reported, and many ethnomedicinal uses, such as the treatment of hematemesis, blood stasis, dysmenorrhea, amenorrhea, epilepsy, spasms, and gastritis, have been recorded. The roots and root bark are the most frequently reported parts of the plants used in medicinal applications. In phytochemical investigations, 451 compounds have been isolated from Paeonia plants to date, which contains monoterpenoid glucosides, flavonoids, tannins, stilbenes, triterpenoids and steroids, and phenols. Studies of their pharmacological activities have revealed the antioxidant, anti-inflammatory, antitumour, antibacterial, antiviral, cardiovascular protective, and neuroprotective properties of the genus Paeonia. In particular, some bioactive extracts and compounds (total glucosides of peony (TGP), paeonol, and paeoniflorin) have been used as therapeutic drugs or tested in clinical trials. In addition to the "incompatibility" of the combined use of "shaoyao" and Veratrum nigrum L. roots in traditional Chinese medicine theory, Paeonia was considered to have no obvious toxicity based on the available toxicological tests.

CONCLUSION

A large number of phytochemical and pharmacological reports have indicated that Paeonia is an important medicinal herb resource, and some of its traditional uses including the treatment of inflammation and cardiovascular diseases and its use as a neuroprotective agent, have been partially confirmed through modern pharmacological studies. Monoterpenoid glucosides are the main active constituents. Although many compounds have been isolated from Paeonia plants, the biological activities of only a few of these compounds (paeoniflorin, paeonol, and TGP) have been extensively investigated. Some paeoniflorin structural analogues and resveratrol oligomers have been preliminarily studied. With the exception of several species (P. suffruticosa, P. ostii, P. lactiflora, and P. emodi) that are commonly used in folk medicine, many medicinal species within the genus do not receive adequate attention. Conducting phytochemical and pharmacological experiments on these species can provide new clues that may lead to the discovery of medicinal resources. It is necessary to identify the effective phytoconstituents of crude extracts of Paeonia that displayed pharmacological activities by bioactivity-guided isolation. In addition, comprehensive plant quality control, and toxicology and pharmacokinetic studies are needed in the future studies.

Rapid identification model based on decision tree algorithm coupling with 1H NMR and feature analysis by UHPLC-QTOFMS spectrometry for sandalwood

Sandalwood is one of the most valuable woods in the world. However, today's counterfeits are widespread, it is difficult to distinguish authenticity. In this paper, similar genus (Dalbergia and Pterocarpus) and confused species (Gluta sp.) of sandalwood were quickly and efficiently identified. Rapid identification model based on ¹H NMR and decision tree (DT) algorithm was firstly developed for the identification of sandalwood, and the accuracy was improved by introducing the AdaBoost algorithm. The accuracy of the final model was above 95%. And the feature components between different species of sandalwood were further explored using UHPLC-QTOFMS and NMR spectrometry. The results showed that 183 compounds were identified, among which 99 were known components, 84 were unknown components. The ¹H NMR and ¹³C NMR signals of 505 samples were assigned, among them, 14 compounds were attributed, characteristic chemical shift intervals with great differences in the model were analysed. Furthermore, the fragmentation pattern of different compounds from sandalwood, in both positive and negative ion ESI modes, was summarized. The results showed a potential and rapid tool based on DT, NMR spectroscopy and UHPLC-QTOFMS, which had performed great potential for rapid identification and feature analysis of sandalwood.

Lignans, flavonoids and coumarins from Viola philippica and their α-glucosidase and HCV protease inhibitory activities

Two lignans including a new one, five flavonoids and five coumarins were isolated from the whole plant of Viola philippica (synonymised as Viola yedoensis Makino). The new compound was structurally determined as (7R,8S,8'S) -3,3'-dimethoxy- 4,4',9-trihydroxy- 7,9'-epoxy-8,8'-lignan 9-O-rutinoside by analysis of its NMR, MS and CD spectroscopic data. The known compounds were characterised by comparing their NMR and MS data with those reported. Among the known compounds, 5-hydroxy-4'-methoxyflavone-7-O- rutinoside, 6,7-di-O-β-D- glucopyranosylesculetin, and 7R,8S-dihydrodehydrodiconiferyl alcohol 4-O-β-D- glucopyranoside were isolated and identified from this genus for the first time. Of these compounds, 5-hydroxy-4'-methoxyflavone-7-O-rutinoside and (7R,8S,8'S) -3,3'-dimethoxy- 4,4',9-trihydroxy- 7,9'-epoxy-8,8'-lignan 9-O-rutinoside were potently active against α-glucosidase, while the two dimeric coumarins, 5, 5'-bi (6, 7-dihydroxycoumarin) and 6,6',7,7'-tetrahydroxy-5,8'-bicoumarin potently inhibited HCV protease.