[A new napthalenone from roots of Rumex nepalensis].

A new napthalenone, rumexone A (1), was isolated from the roots of Rumex nepalensis. The structure of 1 was elucidated by extensive spectroscopic analyses, including 1D and 2D NMR spectra and MS data. Its cytotoxic effect was evaluated using four clinically relevant human cancer cell lines, gastric carcinoma SGC7901, breast carcinoma MDA-MB-231, lung carcinoma A549, and hepatocellular carcinoma HepG2.

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-ß-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.

Antibacterial constituents of Rumex nepalensis spreng and its emodin derivatives.

The CH2Cl2-MeOH (1:1) extract of roots of Rumex nepalensis (Polygonaceae) displayed significant antibacterial activity against five bacterial strains with MICs (62.5-31.2 µg.mL-1). The EtOAc soluble fraction displayed a significant activity against the same strains with MICs (31.2-3.9 µg.mL-1). The purification of the EtOAc fraction yielded one new phenylisobenzofuranone derivative, berquaertiide (1), along with 19 known compounds (2-20). Their structures were elucidated based on the analysis of their NMR and MS data. All the isolated compounds were assessed for their antibacterial activity. Compound 2 was the most active against all the tested strains (15.7 to 1.9 µg.mL-1), while compounds 3-7 displayed good activities on at least one of the tested strains. In addition, seven analogues (21-27) of compound 2 were prepared and further assessed for their antibacterial activity. Compounds 26 and 27 were most active than 2 against Salmonella enterica and Klebsiella pneumoniae with MIC (125 and 15.6 µg.mL-1, respectively).

Biosynthesis of silver nanoparticles using extract of Rumex nepalensis for bactericidal effect against food-borne pathogens and antioxidant activity.

The evolution and incidence of multidrug-resistant food-borne pathogens still become a critical public health global issue. To avert this challenge there is great interest in medical applications of silver nanoparticles. Thus, this study aimed to synthesize silver nanoparticles (Rn-AgNPs) using aqueous leaf extract of Nepal Dock (Rumex nepalensis Spreng) and evaluate their antibacterial potential against food-borne pathogens and antioxidant activity. The Rn-AgNPs were characterized by UV-Vis spectrophotometry, Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), and Fourier Transform Infra-Red Spectroscopy (FTIR). The antibacterial activities of the Rn-AgNPs were evaluated using agar well diffusion (zone of inhibition, ZOI) and microdilution (minimum inhibitory concentration, MIC and minimum bactericidal concentration, MBC) methods. The antioxidant property of the Rn-AgNPs was investigated using radical scavenging (DPPH and hydroxyl) assays. The UV-Vis spectra of Rn-AgNPs elucidated the absorption maxima at 425 nm and FTIR detected numerous functional groups of biological compounds that are responsible for capping and stabilizing Rn-AgNPs. DLS analysis displayed monodispersed Rn-AgNPs of 86.7 nm size and highly negative zeta potential (-32.5 mV). Overall results showed that Escherichia coli was the most sensitive organism, whereas Staphylococcus aureus was the least sensitive against Rn-AgNPs. In the antioxidant tests, the AgNPs radical scavenging activity reached 95.44% at 100 µg/ml. This study indicates that Rn-AgNPs exhibit a strong antimicrobial on L. monocytogenes, S. aureus, S. typhimurium, and E. coli and antioxidant and thus might be developed as a new type of antimicrobial agent for the treatment of multidrug-resistant foodborne pathogens and extensible applications in nanomaterial food- and nanocomposite-based antimicrobial packaging and/or as an antioxidant.

Evaluation of In vivo antidiarrheal activity of hydro-methanolic extract of the root of Rumex nepalensis in Swiss Albino mice.

Background: Natural products have been utilized by human beings for thousands of years to relieve a variety of ailments, including diarrhea. Conventional antidiarrheal drugs are associated with multiple adverse effects and contraindications. Traditionally, Rumex nepalensis by crushing the root, mix with water and then drunk the juice is extensively used for treating diarrhea. However, no scientific research has been done yet to support its antidiarrheal efficacy and safety. Hence, the aim of the study was to evaluate the antidiarrheal activity and safety profile of the plant in mice. Methods: The hydro-methanolic extract was extracted through a cold maceration technique using 80% methanol. Castor oil-induced diarrheal, gastro-intestinal transit, and enteropooling models have been employed to assess the antidiarrheal activity of the test extract at doses of 100, 200, and 400 mg/kg. Results: The crude root extract caused no mortality at a single limit test dose of 2 g/kg throughout the first 24 h and for the rest of the 14 days. In a castor oil-induced diarrheal model, the hydro-methanolic extract markedly delayed the onset of diarrhea, reduced the weight of wet and total feces at 100 (P<.05), 200 (P<.01), and 400 mg/kg (P<.001) test doses. Meanwhile, at 200 (P<.01) and 400 mg/kg (P<.001) doses, the plant extract considerably lowered the weight and volume of intestinal contents. In the gastro-intestinal transit model, however, a dramatic inhibition in the charcoal meal travel was noticed at 100 (P<.05), 200 (P<.01), and 400 mg/kg (P<.001) test doses. The peak antidiarrheal index was exhibited at the highest dose of the test extract. Conclusion: The study speculated that Rumex nepalensis root extract possesses antidiarrheal activity, which could be owing to its inhibitory effect on both gastro-intestinal motility and fluid secretion.

Characterization of the complete chloroplast genome of Rumex nepalensis (Polygonaceae).

Rumex nepalensis (Polygonaceae) is a fairly common perennial herb of high altitudes. In this study, we determined the complete chloroplast genome (plastome) of R. nepalensis with genome-skimming method. The complete plastome of R. nepalensis was 159,110 bp in length with a quadripartite structure, including a large single-copy region of 84,810 bp, a small single-copy region of 13,044 bp, and a pair of inverted repeats regions of 30,628 bp. The overall guanine-cytosine (GC) content was 37.5%. A total of 112 unique genes was annotated in this plastome, including 78 protein-coding genes, 30 tRNA genes, and four rRNA genes. In the ML tree, R. nepalensis was sister to R. crispus, and Rumex was sister to a clade comprising Rheum and Oxyria within Polygonaceae famliy.

Evaluation of Abortifacient Effect of Rumex nepalensis Spreng Among Pregnant Swiss Albino Rats: Laboratory-Based Study.

BACKGROUND: Rumex nepalensis Spreng (Amharic: Yewsha Tult) belongs to the Polygonaceae (buckwheat) family. In Ethiopia, the plant is traditionally used for the treatment of stomach ache, tonsillitis, ascariasis, uterine bleeding, etc. An ethnobotanical study from Mizan-Tepi University also reported the use of the plant by "Shekicho" people as an abortifacient. As a result, this study aimed at the assessment of the outcome of hydro-ethanolic leaves extract of R. nepalensis on Swiss albino pregnant rats and confirm its abortifacient activity. METHODS: The hydro-alcoholic leaves extract of Rumex nepalensis Spreng was evaluated for its abortifacient activity in Swiss albino rats. The mature female rats were mated overnight to male rats in mating cages. Two different dosage regimens (300 mg/kg, 600 mg/kg) of the extract were administered. Laparotomy was performed on the rats to assess the uterus and ovary, the viable, non-viable, adsorbing sites, and corpora lutea. Differences between the experimental and control groups were compared using one-way analysis of variance (ANOVA), followed by Dunnett's T-test to determine their level of significance. RESULTS AND DISCUSSION: This study revealed that Rumex nepalensis Spreng had anti-implantation and abortifacient activities at both 300 and 600 mg/kg doses, which was statistically significant as compared with the controls. It was relatively safe up to the dose of 5000 mg/kg, where no mortality and organ toxicity were manifested. Phytochemicals identified were alkaloids, flavonoids, saponins, tannins, steroids, and anthraquinones. CONCLUSION: In general, our study showed that R. nepalensis had a significant abortifacient activity that testifies its traditional dibs. Therefore, the use of this plant should be avoided in pregnant women to minimize unintended abortion and further studies are needed to know its mechanism of activity and to identify the phytochemicals corresponding to this activity. Checking its efficacy on other species is also needed.

The complete chloroplast genome sequence of Rumex nepalensis Spreng.

Rumex nepalensis is a traditional Chinese herb used for detoxification, hemostasis, and anti-inflammatory. In this study, the complete chloroplast sequence of R. nepalensis was characterized from Illumina pair-end sequencing. The cpDNA was 159,044 bp in length, containing a pair of inverted repeats of 30,623 bp each separated by a large and small single copy region of 84,819 bp and 12,979 bp, respectively. The complete chloroplast genome of R. nepalensis contained 128 genes, 37 tRNA, and 8 rRNA. Phylogenetic tree demonstrated that R. nepalensis was closely related to Rumex acetosa.

Evaluation of the Anti-Ulcer Activity of Hydromethanolic Crude Extract and Solvent Fractions of the Root of Rumex nepalensis in Rats.

BACKGROUND: Rumex nepalensis(RN) Spreng has been used to treat ulcer disease in Ethiopian folk medicine. This study aimed to determine the anti-ulcer activity of hydroalcoholic root crude extract and solvent fractions of R. nepalensis in rats. METHODS: The effect of R. nepalensis crude hydromethanolic extract and solvent fractions at doses (100, 200, 400 mg/kg/day) and repeated dosing (200 mg/kg/day for 10 and 20 days) was examined on ulcers in rats in pyloric ligation-, cold restraint stress-, and acetic acid-induced ulcer models. Cimetidine (100 mg/kg/day) and/or Omeprazole (20 mg/kg/day) were used as standard drugs and served as a positive control. Data were analyzed by one-way ANOVA post hoc followed by a Tukey HSD test with SPSS software version 24.0, and P≤ 0.05 was considered as statistically significant. RESULTS: In the pylorus ligation-induced ulcer model, pretreatment with the crude extract significantly reduced the degree of gastric secretions, pH, total acidity, and ulcerations in a dose-dependent manner. Gastroprotection offered by the R. nepalensis 400 mg/kg test extract was comparable to that of the standard. Among fractions, the ethyl acetate fraction at 400 mg/kg had the highest protection of ulcer but the chloroform fraction was ineffective. In the cold restraint stress-induced ulcer model, R. nepalensis at 200 and 400 mg/kg reduced the lesion index significantly (P<0.01). With relevant chronic ulcer model treatment, a dose of R. nepalensis at 200 and 400 mg/kg healed ulcers significantly with a curative ratio of 53.22% and 54.59%, respectively. CONCLUSION: From this study, it is concluded that hydromethanolic crude extract and solvent fractions of R. nepalensis root showed promising anti-ulcer activity. This upholds its folkloric use. Thus, it is considered as a possible source to develop a new anti-ulcer agent.

Himalayan dock (Rumex nepalensis): the flip side of obnoxious weed.

Himalayan dock (Rumex nepalensis) was evaluated for forage value and antinutrients under three, five and seven weeks cutting intervals in the temperate environment. Dry matter (DM) content was measured for each cutting interval. Forage quality parameters such as Crude Protein (CP), Acid Detergent fiber (ADF), Neutral Detergent Fiber (NDF), Calcium (Ca) and Phosphorus (P) were analyzed. Plants with seven weeks cutting interval gave higher DM yield. CP and P content were significantly higher for three weeks cutting intervals. Average CP contents were 31.38 %, 30.73 % and 27.32 % and average P content 0.58 %, 0.52 % and 0.51 % for three, five and seven weeks cutting intervals, respectively. Ca content did not differ significantly between cutting intervals. The average Ca content were 0.91 %, 0.90 % and 90 %, for three, five and seven weeks cutting intervals, respectively. Tannin and mimosine contents were not significantly different between cutting intervals. Average tannin contents were 1.32 %, 1.27 % and 1.26 % and mimosine 0.38 %, 0.30 % and 0.28 % for three, five and seven weeks cutting intervals, respectively. The study concluded that R. nepalensis could be a potential source of protein for livestock. The study also suggests seven weeks harvesting interval to provide plants with high dry matter yield, high forage quality and very low levels of anti-nutrients.