Simultaneous structural identification of natural products in fractions of crude extract of the rare endangered plant Anoectochilus roxburghii using H NMR/RRLC-MS parallel dynamic spectroscopy

Untargeted metabolomics in Anectocillus roxburghii with habitat heterogeneity and the key abiotic factors affecting its active ingredients

Introduction

Anoectochilus roxburghii is a rare, endangered herb with diverse pharmacological properties. Understanding the main metabolite types and characteristics of wild A. roxburghii is important for efficiently utilizing resources and examining quality according to origin.

Methods

Samples were collected from the main production areas across five regions in Fujian Province, China. An untargeted metabolomics analysis was performed on the entire plants to explore their metabolic profiles. We utilized UPLC-MS/MS to specifically quantify eight targeted flavonoids in these samples. Subsequently, correlation analysis was conducted to investigate the relationships between the flavonoids content and both the biological characteristics and geographical features.

Results

A comprehensive analysis identified a total of 3,170 differential metabolites, with terpenoids and flavonoids being the most prevalent classes. A region-specific metabolite analysis revealed that the Yongchun (YC) region showed the highest diversity of unique metabolites, including tangeretin and oleanolic acid. Conversely, the Youxi (YX) region was found to have the smallest number of unique metabolites, with only one distinct compound identified. Further investigation through KEGG pathway enrichment analysis highlighted a significant enrichment in pathways related to flavonoid biosynthesis. Further examination of the flavonoid category showed that flavonols were the most differentially abundant. We quantified eight specific flavonoids, finding that, on average, the YX region exhibited higher levels of these compounds. Correlation analysis highlighted a significant association between flavonoids and habitat, especially temperature and humidity.

Discussion

Untargeted metabolomics via LC-MS was suitable for identifying region-specific metabolites and their influence via habitat heterogeneity. The results of this study serve as a new theoretical reference for unique markers exclusively present in a specific sample group.

Three new compounds from Anoectochilus roxburghii (Wall.) Lindl

In this study, three new compounds, roxburic acid A (1) and two flavone glycosides isorhamnetin-3-O-α-L-rhamnosyl-(1→6)-β-D-glucopyranose-(1→3)-β-D-glucopyranoside (2), and kaempferol-7-O-β-D-glucopyranosyl-(1→3)-β-D-glucopyranoside (3) were isolated from an ethanol extract of the fresh Anoectochilus roxburghii (Wall.) Lindl., together with 10 known compounds (4-13). The structures of these compounds were comprehensively characterized by HR-ESI-MS, 1H NMR, 13C NMR, and 2 D-NMR. The DPPH free radical scavenging activity of the isolated compounds was evaluated, and the results showed that kaempferol-7-O-β-D-glucopyranosyl- (1→3) -β-D-glucopyranoside (3) and rutin (11) has the potential antioxidant activity with IC50 values of 139 μg/mL and 22.5 μg/mL respectively.

Identification of metabolites from complex mixtures by 3D correlation of 1H NMR, MS and LC data using the SCORE-metabolite-ID approach

Not only in metabolomics studies, but also in natural product chemistry, reliable identification of metabolites usually requires laborious steps of isolation and purification and remains a bottleneck in many studies. Direct metabolite identification from a complex mixture without individual isolation is therefore a preferred approach, but due to the large number of metabolites present in natural products, this approach is often hampered by signal overlap in the respective 1H NMR spectra. This paper presents a method for the three-dimensional mathematical correlation of NMR with MS data over the third dimension of the time course of a chromatographic fractionation. The MATLAB application SCORE-metabolite-ID (Semi-automatic COrrelation analysis for REliable metabolite IDentification) provides semi-automatic detection of correlated NMR and MS data, allowing NMR signals to be related to associated mass-to-charge ratios from ESI mass spectra. This approach enables fast and reliable dereplication of known metabolites and facilitates the dynamic analysis for the identification of unknown compounds in any complex mixture. The strategy was validated using an artificial mixture and further tested on a polar extract of a pine nut sample. Straightforward identification of 40 metabolites could be shown, including the identification of β-D-glucopyranosyl-1-N-indole-3-acetyl-N-L-aspartic acid (1) and Nα-(2-hydroxy-2-carboxymethylsuccinyl)-L-arginine (2), the latter being identified in a food sample for the first time.

Advances in the therapeutic application and pharmacological properties of kinsenoside against inflammation and oxidative stress-induced disorders

Extensive research has implicated inflammation and oxidative stress in the development of multiple diseases, such as diabetes, hepatitis, and arthritis. Kinsenoside (KD), a bioactive glycoside component extracted from the medicinal plant Anoectochilus roxburghii, has been shown to exhibit potent anti-inflammatory and anti-oxidative abilities. In this review, we summarize multiple effects of KD, including hepatoprotection, pro-osteogenesis, anti-hyperglycemia, vascular protection, immune regulation, vision protection, and infection inhibition, which are partly responsible for suppressing inflammation signaling and oxidative stress. The protective action of KD against dysfunctional lipid metabolism is also associated with limiting inflammatory signals, due to the crosstalk between inflammation and lipid metabolism. Ferroptosis, a process involved in both inflammation and oxidative damage, is potentially regulated by KD. In addition, we discuss the physicochemical properties and pharmacokinetic profiles of KD. Advances in cultivation and artificial synthesis techniques are promising evidence that the shortage in raw materials required for KD production can be overcome. In addition, novel drug delivery systems can improve the in vivo rapid clearance and poor bioavailability of KD. In this integrated review, we aim to offer novel insights into the molecular mechanisms underlying the therapeutic role of KD and lay solid foundations for the utilization of KD in clinical practice.

Improved 1D convolutional neural network adapted to near-infrared spectroscopy for rapid discrimination of Anoectochilus roxburghii and its counterfeits

Anoectochilus roxburghii (Wall.) Lindl. (Orchidaceae) is a rare traditional Chinese medicine. For seeking high profit, some traditional Chinese medicine sellers usually adulterated A. roxburghii with Goodyera Schlechtendaliana and Ludisia discolor or directly fake A. roxburghii using Anoectochilus formosanus. These counterfeits with similar appearance greatly influence the prescription efficacy. Therefore, there is an urgent need for an effective and fast authentication method to identify A. roxburghii and its counterfeits. In this paper, the near-infrared spectroscopy (NIRS) data of A. roxburghii and its counterfeits are mearsured. Then, an improved inception architecture based 1-dimensional convolutional neural network (Improved 1D-Inception-CNN) is designed for processing the NIRS data and identifying A. roxburghii and its counterfeits. The Improved 1D-Inception-CNN has less parameters and high calculation efficiency which makes the identification model more practical. The experimental results show that compared with traditional structured CNN models, the complexity of the Improved 1D-Inception-CNN is reduced by 40 %, the parameters are reduced by 50 % and the performances are improved by 1.01 %. Therefore, the Improved 1D-Inception-CNN model based on NIRS technology can effectively and quickly identify A. roxburghii and its counterfeits.

Network Pharmacology Study of the Hepatoprotective Effects of Quercetin-Containing Traditional Chinese Medicine, Anoectochilus roxburghii, and Validation of Quercetin as an Anti-Liver Injury Agent in a Mouse Model of Liver Injury

Background

Anoectochilus roxburghii (Orchidaceae) (AR) has been widely used to treat liver injury in China, but its underlying mechanisms remain elusive. Network pharmacology was utilized to assess the hepatoprotective effects of quercetin (Que)-containing AR, and to validate the anti-liver injury effects of Que in a mouse model of liver injury.

Material/Methods

Network pharmacology analysis was performed to determine bio-active compounds in AR. The core therapeutic targets of AR against liver injury were identified using a protein–protein interaction network. Biological function and pathway enrichment were analyzed based on the identified core therapeutic targets. The hepatoprotective effects of Que in a mouse model of liver injury induced by CCl₄ were assessed to verify the reliability of network pharmacology analysis.

Results

Seven bio-active compounds of AR met drug screening criteria and 17 core therapeutic targets of AR against liver injury were identified. Biological function analysis demonstrated that the therapeutic effects of AR against liver injury were chiefly associated with the suppression of inflammation and immunity; and pathway enrichment analysis showed that nuclear factor-kappa B (NF-κB) and tumor necrosis factor (TNF) signaling pathways were associated with the inflammatory responses. Experimental validation in a mouse model showed that AR exerted anti-inflammatory effects by regulating the NF-κB signaling pathway, a finding that also confirmed the reliability of network pharmacology analysis.

Conclusions

The bio-active compounds identified in AR and the elucidation of their mechanisms of action against liver injury provide a theoretical basis for designing agents that can prevent or suppress liver injury.

Special metabolites isolated from Urochloa humidicola (Poaceae)

This study aims to identify special metabolites in polar extracts from Urochloa humidicola (synonym Brachiaria humidicola) that have allelopathic effects and induce secondary photosensitization in ruminants. The compounds were isolated and identified via chromatographic and spectroscopic techniques. The compounds 4-hydroxy-3-methoxy-benzoic acid, trans-4-hydroxycinnamic acid, and p-hydroxy-benzoic acid; the flavonols isorhamnetin-3-O-β-d-glucopyranoside and methyl quercetin-3-O-β-d-glucuronate; and kaempferitrin, quercetin-3-O-α-l-rhamnopyranoside, and tricin were identified in the extract from the leaves of Urochloa humidicola. Two furostanic saponins, namely, dioscin and 3-O-α-l-rhamnopyranosyl-(1-4)-[α-l-rhamnopyranosyl-(1-2)]-β-d-glucopyranosyl-penogenin, as well as catechin-7-O-β-d-glucopyranoside were identified in the methanolic extract obtained from the roots of this plant. This species features a range of metabolites that may be toxic for animals if used in food and may interfere with the growth medium, thereby inhibiting the development of other species.

Anoectochilus roxburghii: A review of its phytochemistry, pharmacology, and clinical applications

ETHNOPHARMACOLOGICAL RELEVANCE

Anoectochilus roxburghii (Orchidaceae), also known as Jinxianlian (Simplified Chinese: ) and Jinxianlan (Simplified Chinese: ), is valued in many Asian countries, where this plant species is used for medicinal, culinary, and ornamental purposes. As a food, A. roxburghii is widely used as a treatment booster and medicine because of its various beneficial properties; these include, most notably, the curative effects of heat dissipation and cooling of blood, elimination of dampness, detoxification, and immunity enhancement.

AIM OF THIS REVIEW

This review aims to provide up-to-date information on the phytochemistry, pharmacology, and clinical applications of A. roxburghii.

MATERIALS AND METHODS

Relevant information on A. roxburghii was obtained by an online search of worldwide-accepted scientific databases (Web of Science, ScienceDirect, Elsevier, Springer, NCBI, ACS Publications, CNKI, and Wanfang data).

RESULTS

Phytochemical investigations have revealed that the major chemical constituents of A. roxburghii are polysaccharides, flavonoids, glycosides, organic acids, volatile compounds, steroids, triterpenes, alkaloids, and nucleosides. These compounds have been proven to be the main bioactive substances responsible for pharmacological activities such as antidiabetic, antilipemic, anti-inflammatory, antiviral, liver protective, renal protective, immunomodulatory, abirritant, sedative, and antineoplastic effects.

CONCLUSIONS

A variety of dosage forms of A. roxburghii are currently being applied to patients suffering from hyperuricemia, type 2 diabetes mellitus, chronic hepatitis B, Helicobacter pylori infection, cough-variant asthma, and other conditions. Nevertheless, further research is needed to clarify A. roxburghii absorption, distribution, metabolic, and excretion pathways. Moreover, the toxicology in A. roxburghii and A. formosanus are also in urgent need of research, especially long-term in vivo chronic toxicity tests need to be carried out.

Phenolic compounds from Trifolium echinatum Bieb. and investigation of their tyrosinase inhibitory and antioxidant activities

Two bischromones, 3,3'-dimethoxy-2'-oxychromone (1), 3,3'-dihydroxy-2,2'-oxychromone (2) and a biflavone, 5,7,4',5″,3'",4″″-hexahydroxy-3″-O-β-glucosyl-3',7″-O-biflavone (3) have been isolated from whole plant of Trifolium echinatum Bieb. together with five known flavonoids. The structures of the compounds were elucidated by 1D and 2D NMR analysis as well as HRESIMS. The isolated compounds were investigated for their antioxidant activity and tyrosinase inhibitory activity. Highly potent inhibition was found for compounds 1 (IC50=0.41 mM), 5 (IC50=0.47 mM) and 8 (IC50=0.45 mM) compared to those of standard tyrosinase inhibitors kojic acid (IC50=0.67 mM) and l-mimosine (IC50=0.64 mM). The antioxidative effect of the extracts was determined by using β-carotene-linoleic acid, DPPH scavenging, ABTS(+) scavenging, and CUPRAC assays. The experimental findings indicated that the compounds 2 and 8 were found to be active in radical scavenging and CUPRAC assays.

Multidimensional information-based HPLC technologies to evaluate traditional chinese medicine

Traditional Chinese medicines (TCMs) are usually complex mixtures and contain hundreds of chemically different constituents, which make the quality control (QC) of crude drugs and their medical preparations extremely difficult. In the past years, with the rapid development of modern instrumental analysis and computer-aided data processing techniques, great progress has been made in the research of quality standards and the development of QC techniques. Among them, the use of the high-performance liquid chromatography (HPLC) technique is one of the best approaches because of its high separation efficiency. However, one-way separation, single detection methods or data processing cannot meet the needs of the QC of TCMs. Multidimensional information-based HPLC technologies such as two-dimensional HPLC, HPLC coupled with several different detection methods and HPLC fingerprint combined with multicomponent quantification have solved this problem with their comprehensive analysis; these methods have gradually been accepted by more researchers for further in-depth study. The present work provides an overview of the development of QC for TCMs based on HPLC technologies with modern hyphenated techniques, multiseparation methods and some common data processing methods in fingerprint spectra over the last six years.