Two new phenolic glycosides from the rhizome of Gastrodia elata

Glucopyranosyloxybenzyl succinates and their biological activities

Over the past decades, great efforts have been made to explore the glucopyranosyloxybenzyl succinates from Orchidaceae. At the same time, some of those compounds with new structures have led to new findings of their biological functions. The structures, classifications, distributions and bioactivities of glucopyranosyloxybenzyl succinates have been summarized in this review.

Isolation, Bioactivity, and Molecular Docking of a Rare Gastrodin Isocitrate and Diverse Parishin Derivatives from Gastrodia elata Blume

Gastrodia elata Blume (G. elata) is a well-known medicine food homology plant widely used in treating neurological disorders such as Alzheimer's disease (AD). Here, undiscovered gastrodin derivatives were systematically studied. Seven novel gastrodin derivatives (1-7), including a unique gastrodin isocitrate (1) and six differently substituted parishin derivatives (2-7), were isolated. Structural identification was mainly based on 1D and 2D NMR data, high-resolution ESI-MS data, and HPLC analysis. Notably, the stereochemistry of 1 was further elucidated by ECD calculations. Compounds 1 and 6 showed neuroprotective effects on the H2O2-induced PC12 cell injury model. Molecular docking analysis exhibited that 1 and 6 had good affinities with three popular AD-related targets. These findings not only enriched the chemical diversity but also revealed potential active components in G. elata.

Traditional uses, phytochemistry, pharmacology, applications, and quality control of Gastrodia elata Blume: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Gastrodia elata Blume (G. elata) has a long historical application in Asian countries and its tubers, seeds, and stalks are capable of being utilized for medicine, food, or health care products.

AIM OF THE REVIEW

This study aimed to offer a systematic and up-to-date analysis of the current review of the G. elata research advances in traditional uses, phytochemistry, pharmacology, applications, and quality control, as well as a scientific reference for the development and utilization of this plant.

MATERIALS AND METHODS

Electronic databases including PubMed, Web of Science, Google Scholar, ScienceDirect, SciFinder, and CNKI were used for the collection of publications on G. elata. The following keywords of G. elata were used truncated with other relevant topic terms, such as phenolic compounds, polysaccharides, glycosides, neuroprotection, learning and memory improvement effects, cardioprotection, applications, and quality control.

RESULTS AND CONCLUSIONS

Approximately 134 chemical components mainly categorizing as phenolic compounds, polysaccharides, glycosides, organic acids, and sterols were reported from this plant. Moreover, preclinical studies indicated that G. elata performs several functions, including neuroprotection, learning and memory improvement effects, cardioprotection, vaso-modulatory effect, anti-depression, anti-cancer, and other effects. Currently, G. elata has been widely applied to clinics and foods. The available literature shows that the quality of G. elata might be affected by factors such as origin, fungus, and harvest time, which will have an impact on the drug efficacy. According to past research, G. elata is a potential medicinal and edible plant with several active components and pharmacological activity that has a high application value in medicine and the food business. Nevertheless, few studies have concentrated on characterization of polysaccharides structure and study of non-medicinal parts, implying that further comprehensive research on its polysaccharides structure and non-medicinal parts is critical for full utilization of resources of G. elata.

The processing methods, phytochemistry and pharmacology of Gastrodia elata Bl.: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Gastrodia elata Bl. (GE) is one of the rare Chinese medicinal materials with a long history of medicine and cooking. It consists of a variety of chemical components, including aromatic compounds, organic acids and esters, steroids, saccharides and their glycosides, etc., which has medicinal and edible value, and is widely used in various diseases, such as infantile convulsions, epilepsy, tetanus, headache, dizziness, limb numbness, rheumatism and arthralgia. It is also commonly used in health care products and cosmetics. Thus, its chemical composition and pharmacological activity have attracted more and more attention from the scientific community.

AIM

In this review, the processing methods, phytochemistry and pharmacological activities of GE were comprehensively and systematically summarized, which provides a valuable reference for researchers the rational of GE.

MATERIALS AND METHODS

A comprehensive search of published literature and classic books from 1958 to 2023 was conducted using online bibliographic databases PubMed, Google Scholar, ACS, Science Direct Database, CNKI and others to identify original research related to GE, its processing methods, active ingredients and pharmacological activities.

RESULTS

GE is traditionally used to treat infantile convulsion, epilepsy, tetanus, headache, dizziness, limb numbness, rheumatism and arthralgia. To date, more than 435 chemical constituents were identified from GE including 276 chemical constituents, 72 volatile components and 87 synthetic compounds, which are the primary bioactive compounds. In addition, there are other biological components, such as organic acids and esters, steroids and adenosines. These extracts have nervous system and cardiovascular and cerebrovascular system activities such as sedative-hypnotic, anticonvulsant, antiepileptic, neuron protection and regeneration, analgesia, antidepressant, antihypertensive, antidiabetic, antiplatelet aggregation, anti-inflammatory, etc. CONCLUSION: This review summarizes the processing methods, chemical composition, pharmacological activities, and molecular mechanism of GE over the last 66 years, which provides a valuable reference for researchers to understand its research status and applications.

Phytochemical Analysis, Network Pharmacology and in Silico Investigations on Anacamptis pyramidalis Tuber Extracts

Anacamptis pyramidalis (L.) Rich. forms part of the Orchidaceae family that is highlyvalued for its horticultural as well as therapeutic benefits. The present study set out to investigatethe inhibitory activity of A. pyramidalis tubers against key biological targets for the management oftype 2 diabetes, Alzheimer disease, and skin hyperpigmentation. In addition, the antioxidantpotential of the extracts was also assessed using multiple methods. The detailed phytochemicalprofiles of the extracts were determined using high-performance liquid chromatography. Based onqualitative phytochemical fingerprint, a network pharmacology analysis was conducted as well.Parishin was identified from the water extract only, whereas gastrodin and caffeic acid derivativeswere present in the methanol extract. The methanol extract exhibited high inhibitory activityagainst tyrosinase (69.69 mg kojic acid equivalent/g extract), α-amylase (15.76 mg acarboseequivalent/g extract), and α-glucosidase (20.07 mg acarbose equivalent/g extract). Similarly, themethanol extract showed highest antioxidant potential (22.12, 44.23, 45.56, and 29.38 mg Troloxequivalent/g extract, for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), CUPric Reducing Antioxidant Capacity (CUPRAC),and Ferric Reducing Antioxidant Power (FRAP) assays, respectively). Finally, the results ofnetwork pharmacology analysis, besides corroborating traditional uses of plant extracts in themanagement of cold and flu, confirmed a direct involvement of identified phytochemicals in theobserved enzyme inhibitory effects, especially against tyrosinase, α-amylase, and α-glucosidase.Furthermore, based on the results of both colorimetric assays and network pharmacology analysis related to the activity of A. pyramidalis extracts and identified phytocompounds on enzymesinvolved in type 2 diabetes, a docking study was conducted in order to investigate the putativeinteractions of oxo-dihydroxy octadecenoic acid trihydroxy octadecenoic acid against aldosereductase, peroxisome proliferator-activated receptor (PPAR)-α, dipeptidyl peptidase (DPP)-IV,and α-glucosidase. Docking analysis suggested the inhibitory activity of these compounds againstthe aforementioned enzymes, with a better inhibitory profile shown by oxo-dihydroxyoctadecenoic acid. Overall, the present findings supported the rationale for the use of A.pyramidalis as source of bioactive metabolites and highlight, today more than ever, for the strongnecessity of linkage strategy between wild resource valorization and conservation policy.

Traditional Chinese medicine extraction method by ethanol delivers drug-like molecules

Traditional Chinese Medicine (TCM) is an important reservoir for bioactive natural products. TCM extraction methods by water decoction and wine tincture are an integral part of TCM and essential for their widely acknowledged efficacy. In this study, we selected 6 common TCMs that are rich in chemistry to investigate whether the TCM extraction methods deliver molecules with drug-like physical chemical properties. Six TCM herbal materials were extracted by water, 95% ethanol, and sequential hexane, dichloromethane and methanol. The extracts were analyzed by HPLC and ¹H NMR. Isolation on one of the extracts yielded 32 compounds, their physical chemical properties were analyzed by Instant JChem. Our results showed that ethanol extraction, which mimics TCM wine tincture, delivered compounds with physical chemical properties compliant to Lipinski's rule of 5.

Gastrodia elata and epilepsy: Rationale and therapeutic potential

BACKGROUND

Gastrodia elata Blume (G. elata) is a traditional Chinese herb used for centuries in folk medicine. Due to the claimed anticonvulsant properties of G. elata, it is expected that this herb continues to be a target of research, aiming to deepen the available knowledge on its biological activity and safety.

PURPOSE

The current review aims to discuss the most recent advances on the elucidation of the phytochemical composition and anticonvulsant potential of G. elata.

METHODS

Available literature was reviewed from PubMed, ISI Web of Knowledge and Science Direct, using combinations of the following keywords: Gastrodia elata, tianma, epilepsy, anticonvulsant and pharmacokinetics. Abstracts and full texts were evaluated for their clarity and scientific merit.

RESULTS

G. elata rhizome, as well as specific phenolic compounds isolated from this herb, have demonstrated anticonvulsant potential in a variety of in vitro and in vivo models. The pharmacological mechanisms potentially involved in the anticonvulsant activity have been extensively studied, being similar to the known mechanisms claimed for the available antiepileptic drugs. In addition, the pharmacokinetics of the main bioactive component of G. elata (gastrodin) has also been studied.

CONCLUSION

Due to its recognised therapeutic properties, G. elata has gained an increasing interest within the scientific community and, therefore, new medicinal preparations containing G. elata rhizome itself or its bioactive components are expected to be developed in the coming years. Moreover, specific phytochemical constituents isolated from G. elata may also be considered to integrate programs of discovery and development of new anticonvulsant drug candidates.

The rhizome of Gastrodia elata Blume - An ethnopharmacological review

ETHNOPHARMACOLOGICAL RELEVANCE

Gastrodia elata Blume (Orchidaceae) is commonly called Tian ma in Chinese and mainly distributed in the mountainous areas of eastern Asia, such as China, Korea, Japan and India. It is an extensively used traditional Chinese herbal medicine in the clinical practice of traditional Chinese medicine, to treat headache, migraine, dizziness, epilepsy, infantile convulsion, tetany and so on. The present paper reviews the advancements in investigation of botany and ethnopharmacology, phytochemistry, pharmacology, toxicology and quality control of Gastrodia elata Blume. Finally, the possible tendency and perspective for future investigation of this plant are also put forward.

MATERIALS AND METHODS

The information on Gastrodia elata Blume was collected via piles of resources including classic books about Chinese herbal medicine, and scientific databases including Pubmed, Google Scholar, ACS, Web of science, ScienceDirect databases, CNKI and others. Plant taxonomy was validated by the databases "The Plant List", and "Mansfeld's Encyclopedia".

RESULTS

Over 81 compounds from this plant have been isolated and identified, phenolics and polysaccharides are generally considered as the characteristic and active constituents of Gastrodia elata Blume. Its active compounds possess wide-reaching biological activities, including sedative, hypnotic, antiepileptic, anticonvulsive, antianxietic, antidepressant, neuroprotective, antipsychotic, anti-vertigo, circulatory system modulating, anti-inflammationary, analgesic, antioxidative, memory-improving and antiaging, antivirus and antitumor effects.

CONCLUSION

Despite the publication of various papers on Gastrodia elata Blume, there is still, however, the need for definitive research and clarification of other bioactive compounds using bioactivity-guided isolation strategies, and the possible mechanism of action as well as potential synergistic or antagonistic effects of multi-component mixtures derived from Gastrodia elata Blume need to be evaluated. It is also necessary and important to do more quality control and toxicological study on human subjects in order to maintain its efficacy stable in the body and validate its safety in clinical uses. In addition, more investigations on other parts of this plant beyond the tubers are needed. Further studies on Gastrodia elata Blume will lead to the development of new drugs and therapeutics for various diseases, and how to utilize it better should be paid more attention to.

Global profiling and rapid matching of natural products using diagnostic product ion network and in silico analogue database: Gastrodia elata as a case study

Rapid discovery of novel compounds of a traditional herbal medicine is of vital significance for pharmaceutical industry and plant metabolic pathway analysis. However, discovery of unknown or trace natural products is an ongoing challenge. This study presents a universal targeted data-independent acquisition and mining strategy to globally profile and effectively match novel natural product analogues from an herbal extract. The famous medical plant Gastrodia elata was selected as an example. This strategy consists of three steps: (i) acquisition of accurate parent and adduct ions (PAIs) and the product ions data of all eluting compounds by untargeted full-scan MS(E) mode; (ii) rapid compound screening using diagnostic product ions (DPIs) network and in silico analogue database with SUMPRODUCT function to find novel candidates; and (iii) identification and isomerism discrimination of multiple types of compounds using ClogP and ions fragment behavior analyses. Using above data mining methods, a total of 152 compounds were characterized, and 70 were discovered for the first time, including series of phospholipids and novel gastroxyl derivatives. Furthermore, a number of gastronucleosides and phase II metabolites of gastrodin and parishins were discovered, including glutathionylated, cysteinylglycinated and cysteinated compounds, and phosphatidylserine analogues. This study extended the application of classical DPIs filter strategy and developed a structure-based screening approach with the potential for significant increase of efficiency for discovery and identification of trace novel natural products.

Simultaneous Qualitative Assessment and Quantitative Analysis of Metabolites (Phenolics, Nucleosides and Amino Acids) from the Roots of Fresh Gastrodia elata Using UPLC-ESI-Triple Quadrupole Ion MS and ESI- Linear Ion Trap High-Resolution MS

A sensitive, effective and optimized method, based on ultra performance liquid chromatography (UPLC) coupled with ESI-triple quadrupole ion MS and ESI-linear ion trap high-resolution MS, has been developed for the simultaneous quantitative and qualitative determination of phenolics, nucleosides and amino acids in the roots of fresh Gastrodia elata. Optimization of the analytical method provided higher separation efficiency and better peak resolution for the targeted compounds. The simultaneous separation protocols were also optimized by routinely using accurate mass measurements, within 5 ppm error, for each molecular ion and the subsequent fragment ions. In total, 31 compounds, including 23 phenolics, two nucleosides, four amino acids, one gastrodin and one other compound were identified or tentatively characterized. Mono-substituted parishin glucoside (9), methoxy mono-substituted parishin (13), methyl parishin (26), p-hydroxybenzyl di-substituted parishin (29), and p-hydroxybenzyl parishin (31) were tentatively identified as new compounds. Principal metabolite content analysis and the composition of eight representative G. elata cultivars of various species indicated that geographic insulation was the main contributor to clustering.

Comparative pharmacokinetics of gastrodin in rats after intragastric administration of free gastrodin, parishin and Gastrodia elata extract

ETHNOPHARMACOLOGICAL RELEVANCE

Gastrodia elata Blume, a traditional Chinese herb, was widely used against convulsant, vertigo, paralysis, epilepsy, tetanus, asthma and immune dysfunctions. Gastrodin is one of the major bioactive components of G. elata and it is known for its anticonvulsive, anti-inflammatory, antiepileptic and neuroprotective effects.

MATERIALS AND METHODS

An ultra high performance liquid chromatography-fluorescence detection (UHPLC-FLD) method was developed to determine gastrodin in rat plasma. Gastrodin and Thiamphenicol (internal standard, IS) were extracted from rat plasma by immediately protein precipitation. The pharmacokinetics of gastrodin in rats by following differently administered types was studies: intragastric administration of gastrodin (100mg/kg), parishin (116 mg/kg, with the same mole of gastrodin moiety) and G. elata extract (2.3g/kg, with the same mole of gastrodin moiety). Non-compartmental pharmacokinetic profiles were constructed using the software of WinNonlin (Phoenix, version 6.3), and the pharmacokinetic parameters were compared using unpaired Student's t-test.

RESULTS

The results showed that the pharmacokinetic parameters, including Cmax, Tmax, AUC0-∞, t1/2, MRT, Vd, CL, were quite different among the three types of gastrodin administration. The administration of parishin and G. elata extract, which either could convert to gastrodin in vivo or contained free gastrodin and abundant gastrodin conjugates, gave rise to higher elimination half-life (t1/2) and mean residence time (MRT) values for gastrodin compared to free gastrodin administered.

CONCLUSION

The comparison of the pharmacokinetics of gastrodin among three different administered types of gastrodin in rats suggested that administration of parishin or G. elata extract in clinic may result in a longer duration time of action than that of the administration of free gastrodin. The results may provide some guidance for the clinical applications of parishin and G. elata.

Chemical fingerprint and metabolic profile analysis of ethyl acetate fraction of Gastrodia elata by ultra performance liquid chromatography/quadrupole-time of flight mass spectrometry

The chemical fingerprint and metabolic profile of traditional Chinese medicine is very complicated and has been a great challenge. In the present study, chemical fingerprint of ethyl acetate fraction of Gastrodia elata (EtAcGE) and metabolic profile of rat plasma sample after intragastric administration of EtAcGE (2.5g/kg) were investigated using ultra-high performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry (UPLC/Q-TOF MS). A total of 38 chemical constituents of EtAcGE were identified by comparing their retention time, accurate molecular mass and characteristic fragment ions with those of references, or tentatively characterized by comparing molecular formula, fragment ions with that of known compound or information available in literature. And 40 compounds were detected in dosed rat plasma sample, including 16 prototypes and 24 metabolites underwent metabolic process of glucuronidation, glucosylation, sulfation, methylation, hydroxylation, dehydrogenation or mixed modes. The metabolic "soft spots" was hydroxyl or carboxy group. This is the first research for chemical fingerprint and metabolic profile of EtAcGE, which lay a foundation for the further investigation of EtAcGE.

4-Hydroxybenzyl-substituted amino acid derivatives from Gastrodia elata

Seven new 4-hydroxybenzyl-substituted amino acid derivatives (1−7), together with 11 known compounds, were isolated from an aqueous extract of the rhizomes of Gastrodia elata Blume. Their structures were determined by spectroscopic and chemical methods. Compounds 1−3 are pyroglutamate derivatives containing 4-hydroxybenzyl units at the N atom and 4−7 are the first examples of natural products with the 4-hydroxybenzyl unit linked via a thioether bond to 2-hydroxy-3-mercaptopropanoic acid (4−6) and 2-hydroxy-4-mercaptobutanoic acid (7), which would be biogenetically derived from cysteine and homocysteine, respectively. The structures of 1 and 2 were verified by synthesis, while the absolute configurations of 4, 5 and 7 were assigned using Mosher’s method based on the MPA determination rule of Δδ_RS values. The known compound 4-(hydroxymethyl)-5-nitrobenzene-1,2-diol (8) exhibited activity against Fe²⁺-cysteine induced rat liver microsomal lipid peroxidation with IC₅₀ values of 9.99×10⁻⁶ mol/L.

Analysis of the metabolic profile of parishin by ultra-performance liquid chromatography/quadrupole-time of flight mass spectrometry

Parishin is a dominant active ingredient originating from Gastrodia elata Blume, and has good neuroprotective effects against brain disorders. In the present study, the metabolic profile of parishin by in vitro and in vivo experiments was investigated using ultra-high performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry (UHPLC/Q-TOF MS) combined with an automated MS(E) technique. By comparison with reference compounds, accurate mass measurement, the characteristic fragmentation patterns of the parent drug parishin and gastrodin and relevant bio-transformation knowledge, 14 metabolites (seven hydrolyzates and seven derivatives of gastrodin) were detected and identified in rat plasma and urine after intragastric administration of parishin, including processes of hydrolyzation, oxidation, sulfation and glucuronidation. According to the proposed metabolic pathways of parishin, in vitro hydrolytic experiments and metabolic study of gastrodin in rat plasma, it can be inferred that parishin mainly functions as a prodrug and undergoes hydrolysis before being absorbed into the blood. The hydrolyzate, mainly gastrodin, was involved in further metabolism, which was responsible for pharmacological activities of parishin. In conclusion, this work provides valuable information on parishin metabolism using a rapid and reliable UHPLC/Q-TOF MS method, which could be widely used for the metabolic investigation of natural product.

A novel dereplication strategy for the identification of two new trace compounds in the extract of Gastrodia elata using UHPLC/Q-TOF-MS/MS

An ultra performance liquid chromatography (UHPLC) coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOF-MS/MS) was used in the structural determination of natural compounds in Gastrodia elata. A total of 64 compounds were identified or tentatively characterized. The strategy used for characterization was comparing their retention time and fragmentation behaviors with those of the reference standards, or investigating their accurate mass measurements and characteristic fragmentation patterns followed by low-energy collision dissociation tandem mass spectrometry (CID-MS/MS). Phenolic conjugates mainly underwent consecutive losses of gastrodin residues and combined losses of H2O and CO2 from their citric acid units under negative MS/MS conditions. According to these rules, we have successfully characterized fifteen potential novel compounds. To confirm the reliability of this strategy, two targeted unknown trace parishins were obtained from G. elata by LC/MS-guided isolation. Based on the analysis of data from NMR spectroscopy and other techniques, the two unknown parishins were identified as 2-[4-O-(β-d-glucopyranosyl)benzyl]-3-methyl-citrate (parishin J) and 1,2-di-[4-O-(β-d-glucopyranosyl)benzyl]-3-methyl-citrate (parishin K), respectively. The fully established structures were consistent with the MS-oriented structural elucidation. This study expanded our knowledge on parishins in Gastrodia species, and the proposed strategy was proven efficient and reliable in the discovery of new minor compounds from herbal extracts.

Chemical Profiling of an Antimigraine Herbal Preparation, Tianshu Capsule, Based on the Combination of HPLC, LC-DAD-MS (n) , and LC-DAD-ESI-IT-TOF/MS Analyses

Chemical profiling is always the first task in the standardization and modernization of Traditional Chinese Medicine. HPLC and LC-MS were employed to find out the common chromatographic peaks in various batches of Tianshu Capsule (TSC) and the contribution of the characteristic peaks from individual herbs to the whole chromatographic profile of TSC sample. A total of 38 constituents were identified in TSC sample based on the comparison of retention time and UV spectra with authentic compounds as well as by summarized MS fragmentation rules and matching of empirical molecular formula with those of published components. This is the first systematic report on the chemical profiling of the commercial TSC product, which provides the sufficiently chemical evidence for the global quality evaluation of TSC products.

Two new neuroprotective phenolic compounds from Gastrodia elata

Two new phenolic compounds 4-(4'-hydroxybenzyl) phenyl glucoside (gastrodin B, 1) and 1'-hydroxymethyl-phenyl 4-hydroxy-3-(4″-hydroxybenzyl) benzyl ether (gastrol B, 2) were isolated from the rhizomes of Gastrodia elata. Their structures were elucidated on the basis of spectroscopic data and chemical reaction. All compounds exhibited potent neuroprotective activity against H2O2-induced PC12 cell damage.