The genus Rumex (Polygonaceae): an ethnobotanical, phytochemical and pharmacological review

Unravelling the Phytochemical Composition and Antioxidant Potential of Different Parts of Rumex vesicarius L.: A RP-HPLC-MS-MS/MS, Chemometrics, and Molecular Docking-Based Comparative Study

Rumex vesicarius L. Polygonaceae is a wildly grown plant in Egypt, North Africa, and Asia with wide traditional uses. Several studies reported its biological activities and richness in phytochemicals. This research addresses a comprehensive metabolic profiling of the flowers, leaves, stems, and roots via RP-HPLC-QTOF-MS and MS/MS with chemometrics. A total of 60 metabolites were observed and grouped into phenolic acids, flavonoids, phenols, terpenes, amino acids, fatty acids, organic acids, and sugars. Principal component analysis and hierarchal cluster analysis showed the segregation of different parts. Moreover, the antioxidant capacity was determined via several methods and agreed with the previous results. Additionally, an in silico approach of molecular docking of the predominant bioactive metabolites was employed against two antioxidant targets, NADPH oxidase and human peroxiredoxin 5 enzyme (PDB ID: 2CDU and 1HD2) receptors, alongside ADME predictions. The molecular modelling revealed that most of the approached molecules were specifically binding with the tested enzymes, achieving high binding affinities. The results confirmed that R. vesicarius stems and roots are rich sources of bioactive antioxidant components. To our knowledge, this is the first comprehensive metabolic profiling of R. vesicarius giving a prospect of its relevance in the development of new naturally based antioxidants.

Phenolic constituents with potent α-glucosidase inhibitory and cytotoxic activities from Rumex nepalensis var. remotiflorus

Quantitative analysis of Rumex nepalensis var. remotiflorus revealed that its roots contain rich anthraquinones, which has emodin, chrysophanol, and physcion contents of up to 0.30, 0.67, and 0.98 mg/g, respectively. Further phytochemical study led to the isolation and purification of seven undescribed phenolic constituents, including one flavan derivative with a 13-membered ring, polygorumin A (1), two dianthrone glucosides, polygonumnolides F and G (2, 3), two diphenylmethanones, rumepalens A and B (4, 5), and a pair of epimeric oxanthrone C-glucosides, rumejaposides K and L (6a, 6b) from the roots of R. nepalensis var. remotiflorus. Furthermore, 1 undescribed natural product, 1-β-D-glucoside-6'-[(2E)-3-(4-hydroxy-3-methoxyphenyl)-2-propenoate]-3-hydroxy-5-methylphenyl (19), and 21 known phenolic compounds were obtained from the aforementioned plant for the first time. Their structures were elucidated through extensive spectroscopic data analysis. Notably, compounds 1, 4-5, and 7-9 exhibited inhibitory activity on α-glucosidase with IC50 values ranging from 1.61 ± 0.17 to 32.41 ± 0.87 μM. In addition, the isolated dianthrone, chrysophanol bianthrone (14), showed obvious cytotoxicity against four human cancer cell lines (HL-60, SMMC-7721, A-549, and MDA-MB-231) with IC50 values ranging from 3.81 ± 0.17 to 35.15 ± 2.24 μM. In silico target prediction and molecular docking studies demonstrated that the mechanism of the anticancer activity of 14 may be related to the interaction with protein kinase CK2.

Preparation, Isolation and Antioxidant Function of Peptides from a New Resource of Rumexpatientia L. ×Rumextianshanicus A. Los

Rumexpatientia L. ×Rumextianshanicus A. Los (RRL), known as "protein grass" in China, was recognized as a new food ingredient in 2021. However, the cultivation and product development of RRL are still at an early stage, and no peptide research has been reported. In this study, two novel antioxidant peptides, LKPPF and LPFRP, were purified and identified from RRL and applied to H2O2-induced HepG2 cells to investigate their antioxidant properties. It was shown that 121 peptides were identified by ultrafiltration, gel filtration chromatography, and LC-MS/MS, while computer simulation and molecular docking indicated that LKPPF and LPFRP may have strong antioxidant properties. Both peptides were not cytotoxic to HepG2 cells at low concentrations and promoted cell growth, which effectively reduced the production of intracellular ROS and MDA, and increased cell viability and the enzymatic activities of SOD, GSH-Px, and CAT. Therefore, LKPPF and LPFRP, two peptides, possess strong antioxidant activity, which provides a theoretical basis for their potential as food additives or functional food supplements, but still need to be further investigated through animal models as well as cellular pathways.

The Role of Polyphenols in Modulating PON1 Activity Regarding Endothelial Dysfunction and Atherosclerosis

The incidence and prevalence of cardiovascular diseases are still rising. The principal mechanism that drives them is atherosclerosis, an affection given by dyslipidemia and a pro-inflammatory state. Paraoxonase enzymes have a protective role due to their ability to contribute to antioxidant and anti-inflammatory pathways, especially paraoxonase 1 (PON1). PON1 binds with HDL (high-density lipoprotein), and high serum levels lead to a protective state against dyslipidemia, cardiovascular diseases, diabetes, stroke, nonalcoholic fatty liver disease, and many others. Modulating PON1 expression might be a treatment objective with significant results in limiting the prevalence of atherosclerosis. Lifestyle including diet and exercise can raise its levels, and some beneficial plants have been found to influence PON1 levels; therefore, more studies on herbal components are needed. Our purpose is to highlight the principal roles of Praoxonase 1, its implications in dyslipidemia, cardiovascular diseases, stroke, and other diseases, and to emphasize plants that can modulate PON1 expression, targeting the potential of some flavonoids that could be introduced as supplements in our diet and to validate the hypothesis that flavonoids have any effects regarding PON1 function.

Monocyte (THP-1) Response to Silver Nanoparticles Synthesized with Rumex hymenosepalus Root Extract

The study, synthesis, and application of nanomaterials in medicine have grown exponentially in recent years. An example of this is the understanding of how nanomaterials activate or regulate the immune system, particularly macrophages. In this work, nanoparticles were synthesized using Rumex hymenosepalus as a reducing agent (AgRhNPs). According to thermogravimetric analysis, the metal content of nanoparticles is 55.5% by weight. The size of the particles ranges from 5-26 nm, with an average of 11 nm, and they possess an fcc crystalline structure. The presence of extract molecules on the nanomaterial was confirmed by UV-Vis and FTIR. It was found by UPLC-qTOF that the most abundant compounds in Rh extract are flavonols, flavones, isoflavones, chalcones, and anthocyanidins. The viability and apoptosis of the THP-1 cell line were evaluated for AgRhNPs, commercial nanoparticles (AgCNPs), and Rh extract. The results indicate a minimal cytotoxic and apoptotic effect at a concentration of 12.5 μg/mL for both nanoparticles and 25 μg/mL for Rh extract. The interaction of the THP-1 cell line and treatments was used to evaluate the polarization of monocyte subsets in conjunction with an evaluation of CCR2, Tie-2, and Arg-1 expression. The AgRhNPs nanoparticles and Rh extract neither exhibited cytotoxicity in the THP-1 monocyte cell line. Additionally, the treatments mentioned above exhibited anti-inflammatory effects by maintaining the classical monocyte phenotype CD14++CD16, reducing pro-inflammatory interleukin IL-6 production, and increasing IL-4 production.

Anti-Proliferative and Apoptotic Activities of Rumex crispus

Colorectal cancer is the fourth leading cause of cancer death and the third most common cancer diagnosed in the United States. Several anticancer compounds from natural products have been of great interest in cancer chemotherapy and are currently in clinical trials. Natural products that present the targeted killing of cancerous cell and are soluble in water with minimal side effects are ideal candidates. In this study, water-soluble compounds from Rumex crispus plants were screened for anti-proliferative and apoptotic activity against human colorectal adenocarcinoma (DLD-1) cells. The most potent fraction with the highest cell killing and caspase fold change rates was selected for further experiments. The observed changes were further validated by measuring the caspase fold change using RT-qPCR. Furthermore, gene transcript levels were evaluated using an RT2 Profiler assay and a microarray experiment. Our results showed that the most potent L19 fraction exhibits anti-proliferative activity in a dose-dependent manner. The L19 fraction was found to induce apoptotic pathways by triggering different caspases and inflammatory pathways through the activation of non-apoptotic genes. Our study identified and validated the anticancer property of the L19 fraction, which can serve as a strong lead compound for the synthesis of other novel potent analogues.

Four new phenolic constituents from the roots of Rumex dentatus L

Four new phenolic compounds, including two naphthalenes, musizin-8-O-β-D-(6'-O-malonyl-3''-methoxy)glucopyranoside (1) and 2-acetyl-3-methyl-1,4-naphtho-quinone-8-O-β-D-glucopyranoside (2), one chromone, (2'R)-7-hydroxy-2-(2'-hydroxypropyl)-5-methyl acetate chromone (3), and one xanthone, 2,8-dimethyl-3,6-dihydroxyxanthone (4) were isolated from the roots of Rumex dentatus L. (Polygonaceae). In addition, five known including four naphthalenes (5-8) and one chromone (9) were also obtained. Their structures were determined by means of extensive spectroscopic analysis and acidic hydrolysis. Compound 1 showed moderate antifungal activity against Epidermophyton floccosum, with inhibitory rate of 39.539 ± 0.412% at a concentration of 100 μM.

Evaluation of α-Glucosidase Inhibition and Antihyperglycemic Activity of Extracts Obtained from Leaves and Flowers of Rumex crispus L

Among antihyperglycemic drugs used for treating diabetes, α-glucosidase inhibitors generate the least adverse effects. This contribution aimed to evaluate the potential antidiabetic activity of Rumex crispus L. by testing its in vitro α-glucosidase inhibition and in vivo antihyperglycemic effects on rats with streptozotocin (STZ)-induced diabetes. Better inhibition of α-glucosidase was found with the methanol extract versus the n-hexane and dichloromethane extracts. The methanol extract of the flowers (RCFM) was more effective than that of the leaves (RCHM), with an IC50 of 7.3 ± 0.17 μg/mL for RCFM and 112.0 ± 1.23 μg/mL for RCHM. A bioactive fraction (F89s) also showed good α-glucosidase inhibition (IC50 = 3.8 ± 0.11 μg/mL). In a preliminary study, RCHM and RCFM at 150 mg/kg and F89s at 75 mg/kg after 30 days showed a significant effect on hyperglycemia, reducing glucose levels (82.2, 80.1, and 84.1%, respectively), and improved the lipid, renal, and hepatic profiles of the rats, comparable with the effects of metformin and acarbose. According to the results, the activity of R. crispus L. may be mediated by a diminished rate of disaccharide hydrolysis, associated with the inhibition of α-glucosidase. Thus, R. crispus L. holds promise for the development of auxiliary drugs to treat diabetes mellitus.

Antiulcer Activity of Anthraquinone-Flavonoid Complex of Rumex tianschanicus Losinsk

The composition of an ethanol extract from the roots of Rumex tianschanicus Losinsk of the Trans-Ili Alatau wild flora was studied in order to determine its antiulcer activity. The phytochemical composition of the anthraquinone-flavonoid complex from (AFC) R. tianschanicus revealed the presence of numerous polyphenolic compounds, the most abundant of which are anthraquinones (1.77%), flavonoids (6.95%), and tannins (13.39%). The use of column chromatography (CC) and thin-layer chromatography (TLC) in conjunction with UV, IR, NMR spectroscopy, and mass spectrometry data allowed the researchers to isolate and identify the major components of the anthraquinone-flavonoid complex's polyphenol fraction: physcion, chrysophanol, emodin, isorhamnetin, quercetin, and myricetin. The gastroprotective effect of the polyphenolic fraction of the anthraquinone-flavonoid complex (AFC) of R. tianschanicus roots was examined in an experimental model of rat gastric ulcer induced by indomethacin. The preventive and therapeutic effect of the anthraquinone-flavonoid complex at a dose of 100 mg/kg was analyzed using intragastric administration per day for 1 to 10 days, followed by a histological examination of stomach tissues. It has been demonstrated that prophylactic and prolonged use of the AFC R. tianschanicus in laboratory animals resulted in significantly less pronounced hemodynamic and desquamative changes in the epithelium of gastric tissues. The acquired results thus offer fresh insight into the anthraquinone and flavonoid metabolite component composition of R. tianschanicus roots, and they imply that the examined extract can be used to develop herbal medicines with antiulcer activity.

Phenolic Compounds from New Natural Sources-Plant Genotype and Ontogenetic Variation

Phenolic compounds (PCs) are widespread secondary metabolites with potent biological activity. Their sources are mainly plants from cultivated and natural states, providing valuable protective and health-promoting extracts. The wide biological activity of PCs (antioxidant, anti-inflammatory, antimicrobial, antiatherosclerotic, antidiabetic, antiallergic, prebiotic, antimutagenic) means that new sources of PCs are constantly being sought, as exemplified by extracting these compounds from tissue culture or agricultural by-products. Plant phenols show marked qualitative and quantitative variation not only at different genetic levels (between and within species and clones) but also between different physiological and developmental stages. Assessing genetic and seasonal variations in phenolic content and activity allows for selecting the best time to harvest the plant. Learning about the causes of PCs' variability and putting this knowledge into practice can significantly increase PCs' yields and extract the most valuable compounds. The health-promoting properties resulting from consuming products rich in plant PCs are undeniable, so it is worth promoting high-phenolic products as a regular diet. This paper presents an overview of different sources of PCs for use as potential therapeutic alternatives. Additionally, factors of variation in the phenolic complex at the genome and ontogeny levels, relevant in practical terms and as a basis for further scientific research, are presented.