Antioxidant and anti-inflammatory neolignans from the seeds of hawthorn

Deciphering the multi- partite mitochondrial genome of Crataegus pinnatifida: insights into the evolution and genetics of cultivated Hawthorn

Flowering plant (angiosperm) mitochondrial genomes are remarkably dynamic in their structures. We present the complete mitochondrial genome of hawthorn (Crataegus pinnatifida Bunge), a shrub that bears fruit and is celebrated for its extensive medicinal history. We successfully assembled the hawthorn mitogenome utilizing the PacBio long-read sequencing technique, which yielded 799,862 reads, and the Illumina novaseq6000 sequencing platform, which producing 6.6 million raw paired reads. The C. pinnatifida mitochondria sequences encompassed a total length of 440,295 bp with a GC content of 45.42%. The genome annotates 54 genes, including 34 that encode proteins, 17 that encode tRNA, and three genes for rRNA. A fascinating interplay was observed between the chloroplast and mitochondrial genomes, which share 17 homologous sequences sequences that rotal 1,933 bp. A total of 134 SSRs, 22 tandem repeats and 42 dispersed repeats were identified in the mitogenome. Four conformations of C. pinnatifida mitochondria sequences recombination were verified through PCR experiments and Sanger sequencing, and C. pinnatifida mitogenome is more likely to be assembled into three circular-mapping chromosomes. All the RNA editing sites that were identified C-U edits, which predominantly occurred at the first and second positions of the codons. Phylogenetic and collinearity analyses identified the evolutionary trajectory of C. pinnatifida, which reinforced the genetic identity of the hawthorn section. This unveiling of the unique multi-partite structure of the hawthorn mitogenome offers a foundational reference for future study into the evolution and genetics of C. pinnatifida.

Flavan-Benzofurans from Artocarpus lacucha: Their Intracellular Antioxidant Activity and Molecular Docking to Glutathione Reductase

Phytochemical investigation of Artocarpus lacucha Buch.-Ham (Moraceae) leaves led to the identification of three of the rarely found flavan-benzofuranes named artocarpinol C (1), 3-epi-artocarpinol C (2), and artocarpinol D (6) along with six known flavan derivatives. Thus, a total of six artocarpinols are now described. All their chemical structures and absolute configurations were established by one dimensional (1D)- and two-dimensional (2D) NMR, infrared (IR), electronic circular dichroism (ECD), high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS), and optical rotation (OR). Density functional theory (DFT) calculations based on the B3LYP theory level were conducted to determine the stereochemistry at positions 2 and 3 in the C-ring. All compounds exhibited in vitro radical scavenging activities, and compounds 3 and 5 demonstrated pronounced intracellular antioxidative effects in colon carcinoma cells (SW480), as determined by the DCFH-DA assay. Compounds 3 and 5 exhibited further high affinities for binding to the active site of human glutathione reductase. These molecular properties are discussed with regard to possible applications.

Traditional uses, phytochemistry, pharmacology, and safety concerns of hawthorn (Crataegus genus): A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Crataegus (hawthorn), a member of the Rosaceae family, encompasses several species with broad geographical distribution across the Northern Hemisphere, including Asia, Europe, and the Americas. Hawthorn is recognized as an edible medicinal plant with applications related to strengthening the digestive system, promoting blood circulation, and resolving blood stasis.

AIM OF THE REVIEW

This study critically summarized the traditional uses, phytochemistry, and pharmacological properties to provide a theoretical basis for further studies on hawthorn and its applications in medicine and food.

MATERIALS AND METHODS

The available information on hawthorn was gathered from scientific databases (including Google Scholar, Web of Science, PubMed, ScienceDirect, Baidu Scholar, CNKI, online ethnobotanical databases, and ethnobotanical monographs, and considered data from 1952 to 2023). Information about traditional uses, phytochemistry, pharmacology, and safety concerns of the collected data is comprehensively summarized in this paper.

RESULTS

The literature review revealed that hawthorn includes more than 1000 species primarily distributed in the northern temperate zone. Traditional uses of hawthorn have lasted for millennia in Asia, Europe, and the Americas. Within the past decade, 337 chemical compounds, including flavonoids, lignans, fatty acids and organic acids, monoterpenoids and sesquiterpenoids, terpenoids and steroids, have been identified from hawthorn. Modern pharmacological studies have confirmed numerous bioactivities, such as cardiovascular system influence, antitumor activity, hepatoprotective activity, antimicrobial properties, immunomodulatory functions, and anti-inflammatory activities. Additionally, evaluations have indicated that hawthorn lacks toxicity.

CONCLUSIONS

Based on its traditional uses, chemical composition, and pharmacological studies, hawthorn has significant potential as a medicinal and edible plant with a diverse range of pharmacological activities. Traditional uses of the hawthorn include the treatment of indigestion, dysmenorrhea, and osteoporosis. However, modern pharmacological research primarily focuses on its cardiovascular and cerebrovascular system effects, antitumor effects, and liver protection properties. Currently, there is a lack of correlative research involving its traditional uses and pharmacological activities. Moreover, phytochemical and pharmacological research has yet to focus on many types of hawthorn with traditional applications. Therefore, it is imperative to research the genus Crataegus extensively.

Folium crataegi boosts skin regeneration for burn injury in rats through multiple ways

Appropriate topical dressings for burn treatments are important to accelerate skin wound recovery and prevent external infections. This study aimed to evaluate the effect and investigate the mechanism of folium crataegi (Crataegus pinnatifida Bge.) for the treatment of burn wounds, as well as to compare the therapeutic effects of aqueous extracts (HLW) and alcoholic extracts (HLE) from folium crataegi. The results demonstrated that both HLW and HLE groups exhibited a higher wound contraction rate than the silver sulfadiazine (SSD) ointment group. Moreover, HLW showed more significant wound repair effects than HLE. HLW significantly increased levels of EGF and FGF-2 in wound tissue, as well as TGF-β1, VEGF, CAT and IL-10 in serum. Folium crataegi extract, especially aqueous extracts, exerted good anti-inflammatory, anti-oxidant and anti-bacterial effects by upregulating the expression of lag3, txn1 and slpi, respectively. Folium crataegi extract significantly inhibits the expression of npas2, a key gene in the circadian rhythm pathway. In conclusion, this research illustrated that the folium crataegi extract, especially aqueous extracts, had better therapeutic effects on skin burns through multiple ways, possibly including a novel mechanism related to circadian rhythm pathway. These findings suggest that folium crataegi could be a valuable source of compounds for enhancing skin regeneration through multiple ways.

Rapid determination of the relative configuration of diverse 8,4'-oxyneolignans by NMR analysis: Retrospective studies, improvement and structural revision

The characteristic 1H NMR signals (H-7 and H2-9) are significant parameters that have been widely used to assess the relative configuration of H-7 and H-8 of 8,4'-oxyneolignans. However, many usual 8,4'-oxyneolignans cannot be accurately determined by existing NMR methods and no research considering their limitations was performed until now. In this study, the application scope of NMR methods was comprehensively studied and the ΔδH9a-H9b methods have been extended to solve the majority of configuration determination difficulties. The accuracy of extended NMR methods was verified by anisotropic NMR (RCSA measurements), NMR calculation and diverse statistical analysis (MAEΔΔδ, CP3 and DP4+). Furthermore, the theoretical conformational analysis was performed to investigate the inherent limitations of existing NMR methods. This study could provide a valuable reference for determining the relative configuration of H-7 and H-8 in 8,4'-oxyneolignans and the relative configuration of 23 recently reported 8,4'-oxyneolignan derivatives should be reassigned as well.

Structural characterization of a heteropolysaccharide from the fruit of Crataegus pinnatifida and its bioactivity on the gut microbiota of immunocompromised mice

Crataegus pinnatifida is a common food in China, Europe and North America. In order to confirm polysaccharide was the material basis for C. pinnatifida to exert immune regulation. A polysaccharide (CPP) with a molecular weight of 13.58 kDa was isolated from C. pinnatifida. The structure of CPP was determined to be a backbone composed of → 3,5)-α-l-Araf-(1→, with two branches consisting of → 4)-α-d-Galp-(1 → and → 5)-α-l-Araf-(1→, with α-l-Araf and α-d-Manp as the terminal unit. CPP (10 ∼ 500 μg/mL) could promote the secretion of nitric oxide, interleukin-2, interleukin-6 and tumor necrosis factor-α in vitro. CPP could significantly restore the body weight of immunosuppressive mice and improve the immune organ index and interleukin-2, interleukin-6, and tumor necrosis factor-α secretion. In addition, CPP increased the abundance of Bacteroidetes and Verrucomicrobia and decreased the abundance of Proteobacteria at the phylum level. So CPP can regulate the gut microbiota and play an important role in immune regulation.

Advances in the study of the vascular protective effects and molecular mechanisms of hawthorn (Crataegus anamesa Sarg.) extracts in cardiovascular diseases

Hawthorn belongs to the rose family and is a type of functional food. It contains various chemicals, including flavonoids, terpenoids, and organic acid compounds. This study aimed to review the vascular protective effects and molecular mechanisms of hawthorn and its extracts on cardiovascular diseases (CVDs). Hawthorn has a wide range of biological functions. Evidence suggests that the active components of HE reduce oxidative stress and inflammation, regulate lipid levels to prevent lipid accumulation, and inhibit free cholesterol accumulation in macrophages and foam cell formation. Additionally, hawthorn extract (HE) can protect vascular endothelial function, regulate endothelial dysfunction, and promote vascular endothelial relaxation. It has also been reported that the effective components of hawthorn can prevent age-related endothelial dysfunction, increase cellular calcium levels, cause antiplatelet aggregation, and promote antithrombosis. In clinical trials, HE has been proved to reduce the adverse effects of CVDs on blood lipids, blood pressure, left ventricular ejection fraction, heart rate, and exercise tolerance. Previous studies have pointed to the benefits of hawthorn and its extracts in treating atherosclerosis and other vascular diseases. Therefore, as both medicine and food, hawthorn can be used as a new drug source for treating cardiovascular diseases.

Flavonoids with antioxidant and tyrosinase inhibitory activity from corn silk (Stigma maydis)

Corn silk (Stigma maydis), being the styles and stigmas of maize, is a famous traditional medicine and functional tea in China. Research into the chemical composition of corn silk led to the identification of an unreported flavone (1, silkone A), accompanying with three known flavonoids (2-4). And their structures were elucidated through comprehensive spectroscopic analysis. Each obtained compound was evaluated for antioxidant capacity by DPPH, ABTS and FRAP assays. As a result, all tested compounds exhibited stronger radicals scavenging activities than Trolox in ABTS radical assay and displayed relatively weak antioxidant capacity in the other two experiments. Tyrosinase inhibitory activities of compounds 1-4 were also investigated, and compounds 3 and 4 demonstrated moderate inhibitory activities to tyrosinase with IC₅₀ values of 0.49 and 0.21 mM, respectively, which was further investigated through molecular docking calculation. These results may contribute to the development of novel antioxidants and tyrosinase inhibitors from corn silk.

Crataegus pinnatifida: A botanical, ethnopharmacological, phytochemical, and pharmacological overview

ETHNOPHARMACOLOGICAL RELEVANCE

Crataegus pinnatifida belongs to the Rosaceae family and extensively distribute in North China, Europe, and North America. Its usage was first described in "Xinxiu Ben Cao." The dried fruits of Crataegus pinnatifida Bunge or Crataegus pinnatifida var. major N. E. Br., also known as "Shanzha," is a famous medicine and food homology herb with a long history of medicinal usage in China. C. pinnatifida has the functions for digestive promotion, cardiovascular protection, and lipid reduction. It was traditionally used to treat indigestion, cardiodynia, thoracalgia, hernia, postpartum blood stagnation, and hemafecia. In recent years, C. pinnatifida has attracted worldwide attention as an important medicinal and economical crop due to its multiple and excellent health-promoting effects on cardiovascular, nervous, digestive, endocrine systems, and morbigenous microorganisms of the human body due to its medicinal and nutritional values.

AIM OF THE REVIEW

The current review aims to provide a comprehensive analysis of the geographical distribution, traditional usage, phytochemical components, pharmacological actions, clinical settings, and toxicities of C. pinnatifida. Moreover, the connection between the claimed biological activities and the traditional usage, along with the future perspectives for ongoing research on this plant, were also critically summarized.

MATERIALS AND METHODS

We collected the published literature on C. pinnatifida using a variety of scientific databases, including Web of Science, ScienceDirect, PubMed, Wiley, Springer, Taylor & Francis, ACS Publications, Google Scholar, Baidu Scholar, CNKI, The Plant List Database, and other literature sources (Ph.D. and MSc dissertations) from 2012 to 2022.

RESULTS

In the last decade, over 250 phytochemical compounds containing lignans, phenylpropanoids, flavonoids, triterpenoids, and their glycosides, as well as other compounds, have been isolated and characterized from different parts, including the fruit, leaves, and seeds of C. pinnatifida. Among these compounds, flavonoids and triterpenoids were major bioactive components of C. pinnatifida. They exhibited a broad spectrum of pharmacological actions with low toxicity in vitro and in vivo, such as cardiovascular protection, neuroprotection, anti-inflammatory, antioxidant, antibacterial, antiviral, anti-diabetes, anti-cancer, anti-mutagenic, anti-osteoporosis, anti-aging, anti-obesity, and hepatoprotection and other actions.

CONCLUSION

A long history of traditional uses and abundant pharmacochemical and pharmacological investigations have demonstrated that C. pinnatifida is an important medicine and food homology herb, which displays outstanding therapeutic potential, especially in the digestive system and cardiovascular disease. Nevertheless, the current studies on the active ingredients or crude extracts of C. pinnatifida and the possible mechanism of action are unclear. More evidence-based scientific studies are required to verify the traditional uses of C. pinnatifida. Furthermore, more efforts must be paid to selecting index components for quality control research and toxicity and safety studies of C. pinnatifida.

Botany, traditional uses, phytochemistry and pharmacological activity of Crataegus pinnatifida (Chinese hawthorn): a review

OBJECTIVES

Crataegus pinnatifida (C. pinnatifida), including C. pinnatifida Bge. and its variant C. pinnatifida Bge. var. major N, E. Br., has traditionally been used as a homologous plant for traditional medicine and food in ethnic medical systems in China. Crataegus pinnatifida, especially its fruit, has been used for more than 2000 years to treat indigestion, stagnation of meat, hyperlipidemia, blood stasis, heart tingling, sores, etc. This review aimed to provide a systematic summary on the botany, traditional uses, phytochemistry, pharmacology and clinical applications of C. pinnatifida.

KEY FINDINGS

This plant contains flavonoids, phenylpropanoids, terpenoids, organic acids, saccharides and essential oils. Experimental studies showed that it has hypolipidemic, antimyocardial, anti-ischemia, antithrombotic, anti-atherosclerotic, anti-inflammatory, antineoplastic neuroprotective activity, etc. Importantly, it has good effects in treating diseases of the digestive system and cardiovascular and cerebrovascular systems.

SUMMARY

There is convincing evidence from both in vitro and in vivo studies supporting the traditional uses of C. pinnatifida. However, multitarget network pharmacology and molecular docking technology should be used to study the interaction between the active ingredients and targets of C. pinnatifida. Furthermore, exploring the synergy of C. pinnatifida with other Chinese medicines to provide new understanding of complex diseases may be a promising strategy.

Food Applications and Potential Health Benefits of Hawthorn

Hawthorn (Crataegus) is a plant of the Rosaceae family and is widely grown throughout the world as one of the medicinal and edible plants, known as the “nutritious fruit” due to its richness in bioactive substances. Preparations derived from it are used in the formulation of dietary supplements, functional foods, and pharmaceutical products. Rich in amino acids, minerals, pectin, vitamin C, chlorogenic acid, epicatechol, and choline, hawthorn has a high therapeutic and health value. Many studies have shown that hawthorn has antioxidant, anti-inflammatory, anticancer, anti-cardiovascular disease, and digestive enhancing properties. This is related to its bioactive components such as polyphenols (chlorogenic acid, proanthocyanidin B2, epicatechin), flavonoids (proanthocyanidins, mucoxanthin, quercetin, rutin), and pentacyclic triterpenoids (ursolic acid, hawthornic acid, oleanolic acid), which are also its main chemical constituents. This paper briefly reviews the chemical composition, nutritional value, food applications, and the important biological and pharmacological activities of hawthorn. This will contribute to the development of functional foods or nutraceuticals from hawthorn.

Calysepins I-VII, Hexasaccharide Resin Glycosides from Calystegia sepium and Their Cytotoxic Evaluation

Seven new hexasaccharide resin glycosides, named calysepins I-VII (1-7), with 27-membered rings, were obtained from the aerial parts of Calystegia sepium. Their structures with absolute configuration were established on the basis of spectroscopic data interpretation analysis and the use of chemical methods. They were defined as hexasaccharides composed of one d-quinovose, four d-glucose, and one l-rhamnose unit, and their sugar moieties were partially acylated by (2S)-methylbutanoic acid in 1-7 and (2R,3R)-nilic acid in 1-5 and 7, which mainly differed at the positions of acylation. Additionally, calysepin IV (4) exhibited cytotoxicity against A549 cells with an IC₅₀ value of 5.2 μM.

A full set of 8,4'-oxy-8'-phenylneolignan stereoisomers from Sophora tonkinensis and their absolute configurations by TDDFT

A full set of 8,4'-oxy-8'-phenylneolignans with four chiral carbons, named (+)/(-)-leptolepisols D1‒D2 and (+)/(-)-sophorols A‒F, were isolated from the roots and rhizomes of Sophora tonkinensis Gagnep., including 14 previously undescribed stereoisomers, along with 2 known leptolepisol D diastereomers. Their planar structures and relative configurations were elucidated by detailed spectroscopic analysis (HRESIMS and NMR). Based on a highly accurate conformer filtering protocol at low computational cost, the absolute configurations of full set 8,4'-oxy-8'-phenylneolignans were completely assigned by TDDFT calculations of ECD spectra for the first time. Furthermore, (+)/(-)-sophorol A, (-)-sophorol B, and (-)-sophorol E could moderately suppress the lipopolysaccharide-induced nitric oxide production in murine macrophages at 10 μM, with inhibitory ratios of 48.4-52.9%.

Hawthorn (Crataegus spp.): An Updated Overview on Its Beneficial Properties

Medicinal plants, many of which are wild, have recently been under the spotlight worldwide due to growing requests for natural and sustainable eco-compatible remedies for pathological conditions with beneficial health effects that are able to support/supplement a daily diet or to support and/or replace conventional pharmacological therapy. The main requests for these products are: safety, minimum adverse unwanted effects, better efficacy, greater bioavailability, and lower cost when compared with synthetic medications available on the market. One of these popular herbs is hawthorn (Crataegus spp.), belonging to the Rosaceae family, with about 280 species present in Europe, North Africa, West Asia, and North America. Various parts of this herb, including the berries, flowers, and leaves, are rich in nutrients and beneficial bioactive compounds. Its chemical composition has been reported to have many health benefits, including medicinal and nutraceutical properties. Accordingly, the present review gives a snapshot of the in vitro and in vivo therapeutic potential of this herb on human health.

Roles and Mechanisms of Hawthorn and Its Extracts on Atherosclerosis: A Review

Cardiovascular disease (CVD), especially atherosclerosis, is a leading cause of morbidity and mortality globally; it causes a considerable burden on families and caregivers and results in significant financial costs being incurred. Hawthorn has an extensive history of medical use in many countries. In China, the use of hawthorn for the treatment of CVD dates to 659 AD. In addition, according to the theory of traditional Chinese medicine, it acts on tonifying the spleen to promote digestion and activate blood circulation to dissipate blood stasis. This review revealed that the hawthorn extracts possess serum lipid-lowering, anti-oxidative, and cardiovascular protective properties, thus gaining popularity, especially for its anti-atherosclerotic effects. We summarize the four principal mechanisms, including blood lipid-lowering, anti-oxidative, anti-inflammatory, and vascular endothelial protection, thus providing a theoretical basis for further utilization of hawthorn.

New Constituents from the Low Polar Fraction of the Fruits of Crataegus dahurica and Their Anti-Inflammatory Activity in RAW264.7 Cells

The fruit of Crataegus dahurica Koehne was used to treat the disease of infantile indigestion and dyspepsia as an ethnic medicine and food. As a continuous work on finding the active constituents from the edible herbs, four new biphenyl derivatives (1-4), together with two known compounds (5 and 6), were obtained from the petroleum ether fraction of the fruits of C. dahurica. Their structures were determined by the extensive 1D and 2D NMR spectra and HR-MS spectrometry. Furthermore, the anti-inflammatory activities of all the isolated compounds were investigated, in which compound 4 showed moderately inhibitory effects on NO production in RAW264.7 cells without inducing cytotoxicity.

Lignans and Neolignans: Plant secondary metabolites as a reservoir of biologically active substances

Lignans and neolignans are plant secondary metabolites derived from the oxidative coupling of phenylpropanoids. Biological activity of these phenolic compounds ranges from antioxidant, antitumor (terminaloside P, IC₅₀ = 10 nM), anti-inflammatory, anti-neurodegenerative (schibitubin B, IC₅₀ = 3.2 nM) and antiviral (patentiflorin A, IC₅₀ = 14-23 nM) to antimicrobial. In addition, it was observed that several members of this group, namely enterolactone and its biochemical precursors also known as phytoestrogens, possess important protective properties. Most of these lignans and neolignans are presented in reasonable amounts in one's diet and thus the protection they provide against the colon and breast cancer, to name a few, is even more important to note. Similarly, neuroprotective properties were observed (schisanwilsonin G, IC₅₀ = 3.2 nM) These structural motives also serve as an important starting point in the development of anticancer drugs. Presumably the most famous members of this family, etoposide and teniposide, synthetic derivatives of podophyllotoxin, are used in the clinical treatment of lymphocytic leukemia, certain brain tumors, and lung tumors already for nearly 20 years. This review describes 413 lignans and neolignans which have been isolated between 2016 and mid-2018 being reported in more than 300 peer-reviewed articles. It covers their source, structure elucidation, and bioactivity. Within the review, the structure-based overview of compounds as well as the bioactivity-based overview of compounds are described.

Study of the anti-allergic and anti-inflammatory activity of Brachychiton rupestris and Brachychiton discolor leaves (Malvaceae) using in vitro models

Background

Brachychiton rupestris and Brachychiton discolor (Malvaceae) are ornamental trees native to Australia. Some members of Brachychiton and its highly related genus, Sterculia, are employed in traditional medicine for itching, dermatitis and other skin diseases. However, scientific studies on these two genera are scarce. Aiming to reveal the scientific basis of the folk medicinal use of these plants, the cytotoxicity, anti-inflammatory and anti-allergic activities of Brachychiton rupestris and Brachychiton discolor leaves extracts and fractions were evaluated. Also, phytochemical investigation of B. rupestris was performed to identify the compounds exerting the biological effect.

Methods

Extracts as well as fractions of Brachychiton rupestris and Brachychiton discolor were tested for their cytotoxicity versus hepatoma HepG2, lung A549, and breast MDA-MB-231 cancer cell lines. Assessment of the anti-allergic activity was done using degranulation assay in RBL-2H3 mast cells. Anti-inflammatory effect was tested by measuring the suppression of superoxide anion production as well as elastase release in fMLF/CB-induced human neutrophils. Phytochemical investigation of the n-hexane, dichloromethane and ethyl acetate fractions of B. rupestris was done using different chromatographic and spectroscopic techniques.

Results

The tested samples showed no cytotoxicity towards the tested cell lines. The nonpolar fractions of both B. rupestris and B. discolor showed potent anti-allergic potency by inhibiting the release of β-hexosaminidase. The dichloromethane fraction of both species exhibited the highest anti-inflammatory activity by suppressing superoxide anion generation and elastase release with IC₅₀ values of 2.99 and 1.98 μg/mL, respectively for B. rupestris, and 0.78 and 1.57 μg/mL, respectively for B. discolor. Phytochemical investigation of various fractions of B. rupestris resulted in the isolation of β-amyrin acetate (1), β-sitosterol (2) and stigmasterol (3) from the n-hexane fraction. Scopoletin (4) and β-sitosterol-3-O-β-D-glucoside (5) were obtained from the dichloromethane fraction. Dihydrodehydrodiconiferyl alcohol 4-O-β-D-glucoside (6) and dihydrodehydrodiconiferyl alcohol 9-O-β-D-glucoside (7) were separated from the ethyl acetate fraction. Scopoletin (4) showed anti-allergic and anti-inflammatory activity.

Conclusions

It was concluded that the nonpolar fractions of both Brachychiton species exhibited anti-allergic and anti-inflammatory activities.

Electronic supplementary material

The online version of this article (10.1186/s12906-018-2359-6) contains supplementary material, which is available to authorized users.

Resin glycosides from the seeds of Ipomoea muricata and their multidrug resistance reversal activities

Resin glycosides represent an important chemotaxonomic marker of the Convolvulaceae family and possess multidrug resistance (MDR) reversal activity. In our recent study, nine previously undescribed resin glycosides, Calonyctins B-J, were isolated from the seeds of Ipomoea muricata. Their structures with the absolute configuration were established on the basis of comprehensive spectroscopic analysis and chemical methods. Among these, Calonyctins F-I possessed a skeleton in which the aglycone moiety and the oligosaccharide core were linked by a 3-hydroxy-2-methylbutanoic acid moiety to form a 25-membered macrocyclic structure. Calonyctins E, J, and muricatic acid C methyl ester were non-cytotoxic but enhanced the cytotoxicity of vincristine by 2.5-407.1 fold at 25 μM in KB/VCR cells. Calonyctin E was the most active one.

Natural Products Research in China From 2015 to 2016

This review covers the literature published by chemists from China during the 2015-2016 on natural products (NPs), with 1,985 citations referring to 6,944 new compounds isolated from marine or terrestrial microorganisms, plants, and animals. The emphasis is on 730 new compounds with a novel skeleton or/and significant bioactivity, together with their source organism and country of origin.