Phytochemicals and Antimicrobial Activities of Rumex nervosus Natural Populations Grown in Sarawat Mountains, Kingdom of Saudi Arabia

Antibacterial activity and phytochemical screening of traditional medicinal plants most preferred for treating infectious diseases in Habru District, North Wollo Zone, Amhara Region, Ethiopia

Ethiopia's healthcare system relies on traditional medicinal practices that use medicinal plants to treat human and livestock ailments. However, the lack of empirical validation regarding the efficacy of these treatments against specific infectious diseases necessitates rigorous scientific investigations. The objective of this study was to investigate the antibacterial activity and phytochemical screening on five selected medicinal plant species, namely Solanum somalense Franchet., Verbascum sinaiticum Benth., Rumex nervosus Vahl, Withania somnifera (L.) Dunal and Calpurnia aurea (Ait.) Benth. The plants were first identified jointly with local informants and later considering mainly their high informant consensus and fidelity level values for their efficacy in treating infectious diseases in the area. Ethanol and aqueous extracts were prepared from the plant materials, and their antibacterial activities were evaluated against standard bacterial strains, representing both gram-positive and gram-negative types. To assess the antibacterial activity of the extracts, the minimum inhibitory concentration (MIC) was determined using the broth dilution method. Additionally, phytochemical screening was performed using standard qualitative tests to identify various secondary metabolites. The results indicated antibacterial efficacy in the ethanol extracts of S. somalense, W. somnifera, and C. aurea against particular bacterial strains (S. somalense against S. agalactiae with MIC of 1.5 mg/mL; W. somnifera against S. aureus and E. coli, with MIC of 2 mg/mL; C. aurea against E. coli and K. pneumoniae, with MICs of 3 mg/mL and 3.5 mg/mL, respectively). The results of the phytochemical screening indicated the presence of steroids, alkaloids, flavonoids, saponins, and terpenoids. The selected medicinal plants demonstrated promising antibacterial activity against certain bacterial strains. The current findings support the long-standing claim of the traditional medical system of the study area for their continued use of these plants in their treatment of infectious diseases. Further investigation is required to isolate the responsible active compounds and characterize the constituents and description of their antibacterial effect for possible use in areas where these infectious diseases are major health problems.

Biosynthesis of Silver Nanoparticles and Exploring Their Potential of Reducing the Contamination of the In Vitro Culture Media and Inducing the Callus Growth of Rumex nervosus Explants

Among biological methods, green synthesis of the nanomaterials using plant extracts was shown to be an environmentally friendly, economical, and simple approach. In the current study, the biogenic synthesis of silver nanoparticles (AgNPs) was achieved using the leaf extract of Hibiscus tiliaceus, in order to prevent the contamination of the tissue culture media and induce callus growth. The nanostructures of the fabricated AgNPs were characterized using UV-visible spectroscopy, Fourier transform infra-red spectra (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), zeta size, and zeta potential techniques. Our results indicate that The UV-vis spectrum of AgNPs exhibited an absorption band at 415 nm. The FTIR analysis identified the functional groups which could involve in the reduction of silver ions to AgNPs, this was also confirmed by the (hkl) diffraction peaks in the XRD diffractogram. Moreover, the TEM analysis showed a spherical nanoparticle with a size ranging from 21 and 26 nm. Thereafter, the potential antibacterial and antifungal activity of the biogenic AgNPs was evaluated against Bacillus pumilus and Alternaria alternata which were isolated from the in vitro culture media and identified based on 16S rDNA and ITS rDNA sequences, respectively. The results showed that the AgNPs significantly inhibited the growth of Alternaria alternata and Bacillus pumilus at all applied concentrations (5, 10, 20 and 40 mg/L). Compared to the control more fungal radial growth reduction (42.59%,) and bacterial inhibition (98.12%) were registered in the plates containing high doses of AgNPs (40 mg/L). Using Rumex nervosus explants, the biosynthesized AgNPs were tested for their impact to promote callus growth. The obtained results showed a significant effect of AgNPs on callus fresh weight at all applied doses. Moreover, AgNPs treatments showed a polymorphism of 12.5% which was detected by RAPD markers. In summary, the results revealed that AgNPs (40 mg/L) can be effectively added to the in vitro culture media for reducing microbial contamination and improving callus growth while greatly maintaining its genetic stability.

In vitro phytochemical analysis and antibacterial and antifungal efficacy assessment of ethanolic and aqueous extracts of Rumex nervosus leaves against selected bacteria and fungi

Background and Aim

Scientists are interested in identifying natural antibiotic substitutes that are effective against drug-resistant pathogenic microbes and spoilage fungi to counter pathogens and reduce the major public health problem of antibiotic residues in animal products. This study aimed to evaluate the antimicrobial activity of Rumex nervosus leaves (RNLs) as a medicinal herb against four bacterial and two fungal strains using absolute ethanol, 50% ethanol, and aqueous extracts.

Materials and Methods

The antimicrobial activities of various RNL extracts against selected microbes were evaluated using the disk diffusion antibiotic susceptibility test, minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs), minimum fungicidal concentrations, and the poisoned food technique.

Results

The absolute ethanol RNL extract showed the best bacteriostatic/bactericidal activity against Salmonella Typhimurium, Escherichia coli, and Staphylococcus aureus (MIC/MBC: 0.20/0.40, 0.20/0.40, and 0.32/0.65 mg/mL, respectively). The diameter of the zone of inhibition was larger (p < 0.05) for the 100% ethanol RNL extract (8.17 mm) against Salmonella Typhimurium, the 50% ethanol-RNL extract (11.5 mm) against E. coli, and the aqueous RNL extract (14.0 mm) against S. aureus than for any other bacterial isolate. The aqueous RNL extract strongly (p < 0.0001) inhibited the mycelial growth of Aspergillus fumigatus (100%) and Aspergillus niger (81.4%) compared with the control.

Conclusion

The results of this study suggest that RNL is a promising new natural antimicrobial agent for food preservation. To date, most research on the antimicrobial properties of natural herbs has been conducted in vitro, with few exceptions in vivo and intervention-based research.

Antioxidant and antimicrobial potential of two extracts from Capparis spinosa L. and Rumex nervosus and molecular docking investigation of selected major compounds

The present study examined the phytochemical composition, antioxidant, antimicrobial properties, and molecular docking of different solvents extracts (methanol and water) of two medicinal plants, namely, Capparis spinosa L (CS) and Rumex nervosus (RN). Phytochemical analysis showed that total phenol, flavonoids, alkaloids, and vitamin C were significantly (P ≤ 0.05) higher in the methanolic extract of both plants than in other solvents. However, tannin content was significantly (P ≤ 0.05) high in the water extract for both plants. Chloroform and acetone extracts were significantly lower in phytochemicals than other solvents, therefore excluded in this study. GC–MS analysis showed one dominant compound in CS (isopropyl isothiocyanate) and two in RN (pyrogallol and palmitic acid). The antioxidant methods applied (DPPH, ABTS, β-Carotene/linoleic acid assay, and reducing the power) showed that the methanolic extract of CS exerted higher activity in methanolic extract but lower than that of BHA standard. The methanolic extract of both plants inhibited the bacterial pathogens when a minimum inhibitory concentration (MIC) method was applied, compared to water extract with RN-methanolic extract had a lower inhibition concentration than CS-methanolic extract. The molecular interactions study revealed that the palmitic acid and pyrogallol interacted with the receptors' active site. This work concluded that CS and RN showed a remarkable antioxidant and antibacterial effect with the high antimicrobial activity of RN extract.

Rumex nervosus could alleviate streptozotocin-induced diabetic nephropathy in rats by activating Nrf2 signaling

This study tested the protective effect of Rumex nervous (R. nervosus) methanol extract against streptozotocin (STZ)-mediated type 1 diabetes mellitus (T1DM)-induced nephropathy in rats and examined if this protection involves activating the nuclear factor erythroid 2 related factor-2 (Nrf2). Rats were divided into control, R. nervous (300 mg), STZ (T1DM), STZ + R. nervosus (100, 200, or 300 mg/kg), and STZ + R. nervosus (300 mg/kg) + brusatol (an Nrf2 inhibitor). With no effect on fasting glucose and insulin levels, R. nervosus methanol extract preserved kidney histological structure and alterations kidney function markers (e.g. albumin, creatinine, and urine volume) in the STZ-diabetic rats. R. nervosus also reduced levels of reactive oxygen species (ROS), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), and interleukine-6 (IL-6), nuclear levels of the nuclear factor kappa beta (NF-κB), and mRNA of caspase-3 and Bax in the kidneys of these diabetic rats. Concomitantly, it stimulated renal mRNA levels of Bcl2 and Nrf2, cytoplasmic and nuclear levels of Nrf2, and levels of glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). All these effects were dose-dependent, with the maximum effect seen with the 300 mg/kg dose, all prevented by brusatol. Also, these effects occurred without any alteration in the transcription of the Kelch-like ECH-associated protein 1 (keap-1). Similar effects on levels of GSH, SOD, CAT, and NF-κB, as well as expression of Nrf2, were also observed in the kidney of control + R. nervous-treated rats. In conclusion, R. nervosus prevents diabetic nephropathy in rats by upregulating and activating Nrf2.

Ethnoveterinary Uses of Certain Yemeni Plants: A Review of the Scientific Evidence

Livestock is an important and integral component of agriculture production in Yemen and contributes 28% of the total agricultural production income. Research in the field of Yemeni ethnoveterinary medicine is limited to a few studies. Therefore, our work aims to substantiate scientifically the ethnoveterinary use of some documented plant species based on a literature review of their bioactivities and toxicological properties. Searching the scientific literature has revealed various pharmacological activities that may support the claimed healing activities of 11 out of 14 plant species for some of their ethnoveterinary utilization. This comprises the use of Aloe spp. latex for constipation, worms, boils, and wounds; Boswellia sacra underbark for wounds and its oleo-gum resin for mastitis; Soqotraen Boswellia species as an insect repellent; Cissus rotundifolia for stomach pain; Cyphostemma digitatum as an appetite stimulant; Psiadia punctulate for bone fracture; Pulicaria undulata as an insect repellent; combinations of Aristolochia bracteolate with Sorghum bicolor grains for bloating; Rumex nervosus and salt for eye pimples; and Trigonella foenum-graecum seeds with Hordeum vulgare grains for constipation. Some plants were found to demonstrate various toxic effects in in vivo and in vitro experimental studies. The local administration of Calotropis procera latex was also reported to induce an intense inflammatory response. It can be concluded that our work has provided valuable scientific information on the biological and toxic activities of some Yemeni ethnoveterinary remedies that could be utilized for the benefit of farmers to ration the use of these remedies and avoiding their toxicity.

Rumex nervosus leaves meal improves body weight gain, duodenal morphology, serum thyroid hormones, and cecal microflora of broiler chickens during the starter period

A total of 192 one-day-old Ross 308 broiler chicks were assigned to 4 treatments with 8 replicate cages of 6 chicks (3♀ and 3♂) per cage according to a completely randomized block design. The dietary treatments were a basal diet (control) and a control diet supplemented with 1,000, 3,000, and 5,000 mg/kg Rumex nervosus leaves meal (RN). Gallic acid and some volatile compounds were detected in the RN extract. On day 10 of age, BW was improved (P = 0.016) with supplemental RN (1,000-5,000 mg/kg). On day 14 of age, dietary application of RN up to 3,000 mg/kg increased BWG (P = 0.003) compared with control, while a 1,000 mg/kg RN had the best feed conversion ratio (P = 0.016). On day 10 of age, samples were taken on a single female bird per replicate. The addition of RN (1,000-5,000 mg/kg) increased (P < 0.001) serum albumin and triiodothyronine levels and maximized the relative weight of breast meat (P = 0.003). Feeding a diet with 1,000 mg/kg RN resulted in greater duodenal villus height (P < 0.001) than control and the diet with 5,000 mg/kg RN. Broilers fed diet supplemented with 1,000 mg/kg RN had the best duodenal villus surface area (P < 0.001). Feeding a diet with 1,000 mg/kg RN decreased (P < 0.001) cecal Escherichia coli count compared with control and the diet with 5,000 mg/kg RN. Salmonella spp. count tended to increase with 5,000 mg/kg RN leaves meal (P = 0.069, linear P = 0.026). In conclusion, R. nervosus leaves meal could be considered as a phytogenic feed additive in broiler diets up to a 1,000-mg/kg inclusion rate because of its combined positive effects on BWG, feed conversion ratio, villus height, villus surface area, serum albumin and triiodothyronine hormone, and cecal E. coli during the starter period (day 10-14 of age). Further study is required to elucidate its molecular mechanism.