Antimicrobial, antitrypanosomal and antibiofilm activity of Equisetum hyemale

From Stem to Spectrum: Phytochemical Characterization of Five Equisetum Species and Evaluation of Their Antioxidant Potential

The Equisetaceae family, commonly known as horsetails, has been of scientific interest for decades due to its status as one of the most ancient extant vascular plant families. Notably, the corresponding species have found their place in traditional medicine, offering a wide array of applications. This study presents a comprehensive phytochemical analysis of polar secondary metabolites within the sterile stems of five distinct Equisetum species using HPLC-DAD-ESI-MSn. For this purpose, fresh plant material was extracted with acetone/water, and the resulting crude extracts were fractionated using dichloromethane, ethyl acetate, and n-butanol, respectively. The results reveal a complex array of compounds, including hydroxycinnamic acids, hydroxybenzoic acids, flavonoids, and other phenolic compounds. In addition, total phenolic contents (Folin-Ciocalteu assay) and antioxidant activities (DPPH assay) of the plant extracts were evaluated using spectrophotometric methods. The present comparative analysis across the five species highlights both shared and species-specific metabolites, providing valuable insights into their chemical diversity and potential pharmacological properties.

Genus Equisetum L: Taxonomy, toxicology, phytochemistry and pharmacology

INTRODUCTION

The genus Equisetum (Equisetaceae) is cosmopolitan in distribution, with 41 recognized species. Several species of Equisetum are widely used in treating genitourinary and related diseases, inflammatory and rheumatic problems, hypertension, and wound healing in traditional medicine practices worldwide. This review intends to present information on the traditional uses, phytochemical components, pharmacological activities, and toxicity of Equisetum spp. and to analyze the new insights for further study.

METHODS

Relevant literature has been scanned and collected via various electronic repositories, including PubMed, Science Direct, Google Scholar, Springer Connect, and Science Online, from 1960 to 2022.

RESULTS

Sixteen Equisetum spp. were documented as widely used in traditional medicine practices by different ethnic groups throughout the world. A total of 229 chemical compounds were identified from Equisetum spp. with the major group of constituents being flavonol glycosides and flavonoids. The crude extracts and phytochemicals of Equisetum spp. exhibited significant antioxidant, antimicrobial, anti-inflammatory, antiulcerogenic, antidiabetic, hepatoprotective, and diuretic properties. A wide range of studies have also demonstrated the safety of Equisetum spp.

CONCLUSION

The reported pharmacological properties of Equisetum spp. support its use in traditional medicine, though there are gaps in understanding the traditional usage of these plants for clinical experiments. The documented information revealed that the genus is not only a great herbal remedy but also has several bioactives with the potential to be discovered as novel drugs. Detailed scientific investigation is still needed to fully understand the efficacy of this genus; hence, very few Equisetum spp. were studied in detail for phytochemical and pharmacological investigation. Moreover, its bioactives, structure-activity connection, in vivo activity, and associated mechanism of action ought to be explored further.

Horsetail (Equisetum hyemale) Extract Accelerates Wound Healing in Diabetic Rats by Modulating IL-10 and MCP-1 Release and Collagen Synthesis

Traditionally, Equisetum hyemale has been used for wound healing. However, its mechanism of action remains to be elucidated. For this purpose, a 40% ethanolic extract of E. hyemale was prepared. Phytochemical screening revealed the presence of minerals, sterols, phenolic acids, flavonols, a lignan, and a phenylpropenoid. The extract reduced the viability of RAW 264.7 cells and skin fibroblasts at all times evaluated. On the third day of treatment, this reduction was 30–40% and 15–40%, respectively. In contrast, the extract increased the proliferation of skin fibroblasts only after 48 h. In addition, the extract increased IL-10 release and inhibited MCP-1 release. However, the extract did not affect both TGF-β1 and TNF-α released by RAW 264.7 cells. The higher release of IL-10 could be related to the up-/downregulation of inflammatory pathways mediated by the extract components associated with their bioactivity. The extract inhibited the growth of Staphylococcus aureus and Escherichia coli. Topical application of the extract accelerated wound healing in diabetic rats by increasing fibroblast collagen synthesis. These results suggest that E. hyemale extract has great potential for use in the treatment of wounds thanks to its phytochemical composition that modulates cytokine secretion, collagen synthesis, and bacterial growth.

A comprehensive review of herbacetin: From chemistry to pharmacological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Herbacetin is an active constituent of traditional Chinese medicines such as Ephedra sinica Stapf (MaHuang) and Sedum roseum (L.). Scop. (Hong JingTian). MaHuang was used to treat cough, asthma, fever, and edema for more than 5000 years, while Hong JingTian was used to treat depression, fatigue, cancers, and cardiovascular disease. Recent studies indicate that herbacetin and its glycosides play a critical role in the pharmacological activities of these herbs. However, currently, no comprehensive review on herbacetin has been published yet.

AIM OF THE STUDY

This review aimed to summarize information on the chemistry, natural sources, and pharmacokinetic features of herbacetin, with an emphasis on its pharmacological activities and possible mechanisms of action.

MATERIALS AND METHODS

A literature search was performed on the Web of Science, PubMed, and China Knowledge Resource Integrated databases (CNKI) using the search term "herbacetin" ("all fields") from 1935 to 2020. Information was also obtained from classic books of Chinese herbal medicine, Chinese pharmacopeia, and the database "The Plant List" (www.theplantlist.org). Studies have been analyzed and summarized in this review if they dealt with chemistry, taxonomy, pharmacokinetic, and pharmacological activity.

RESULTS

Herbacetin is distributed in various plants and can be extracted or synthesized. It showed diverse pharmacological activities including antioxidant, antiviral, anti-inflammatory, anticancer, antidiabetic, and anticholinesterase. It is thought to have great potential in cancer treatment, especially colon and skin cancers. However, the bioavailability of herbacetin is low and the toxicity of herbacetin has not been studied. Thus, more studies are required to solve these problems.

CONCLUSIONS

Herbacetin shows promising pharmacological activities against multiple diseases. Future research should focus on improving bioavailability, further studying its pharmacological mechanism, evaluating its toxicity and optimal dose, and performing the clinical assessment. We hope that the present review will serve as a guideline for future research on herbacetin.

Antibiofilm and Anti-Candidal Activities of the Extract of the Marine Sponge Agelas dispar

This study aimed to determine the antifungal and antibiofilm activities of Agelas dispar on biofilm-producing Candida species. The methanolic extract of A. dispar was obtained and the fraction Ag2 showed inhibitory activity for all 13 Candida strains tested, in concentrations ranging from 2.5 to 0.15625 mg/mL. Antifungal activity of fungicidal nature was seen between 5.0 and 0.3125 mg/mL of extract against the strains. All the strains were classified as biofilm producers. The methanolic extract Ag2 was tested at concentrations of 2.5 and 1.25 mg/mL for antibiofilm activity against the biofilm formation and maturation in all the strains of the genus Candida. Treated and untreated biofilm samples were selected for visualization using scanning electron microscopy (SEM). SEM allowed the visualization of the quantitative decrease in the microbial community, alterations of structural morphology, and destruction of both the formation and maturation of biofilms, at the cellular level. The mechanism of action of this fraction is suggested to be at the plasma membrane and/or cell wall alteration level. Therefore, the use of the methanolic extract of A. dispar may be a promising antifungal and antibiofilm therapeutic strategy against different species of the genus Candida.

Chemical profiling and antioxidant activity of Equisetum ramosissimum Desf. stem extract, a potential traditional medicinal plant for urinary tract infections

Background

Equisetum ramosissimum Desf. (E. ramosissimum) is a widely used traditional medicinal plant to treat urinary tract infections (UTIs) by ethnic people throughout the world. The utility of the plant in treating urinary-related disorders was evaluated against selected pathogenic bacteria which has major role in causing UTIs. Hence, the present study executed to extract phytochemicals like total phenolics and flavonoids, chemical profiling by GC–MS analysis and to test their antioxidant activity from stem extracts of E. ramosissimum. The extraction process was directed by petroleum ether, chloroform, ethyl acetate, methanol, and aqueous solvents.

Results

The GC–MS analysis yielded 24 phytoconstituents with linoleic acid, palmitic acid, nonacosane, hexahydrofarnesyl acetone, and octacosane as major compounds. Methanolic extract yielded maximum amount of phenolics (TPC) and flavonoids (TFC) with 600.02 ± 0.22 mg GAE/g and 631.38 ± 0.69 mg QE/g, respectively. Methanolic extract also exhibited notable free radical scavenging activity with an IC50 of 123.89 ± 0.73, 150.10 ± 1.02, 146.01 ± 0.54, and 63.73 ± 6.12 µg/mL for DPPH, FRAP, ABTS, and O2− assays, respectively. The minimum inhibitory concentration (MIC) required to inhibit the growth of tested pathogenic bacteria was observed in aqueous and methanolic extracts with the value being 31.25 µg/mL against R. equi and V. cholerae. As like, methanolic and petroleum ether extracts efficiently inhibited the growth of B. subtilis with the MIC of 31.25 µg/mL.

Conclusion

It was concluded that the notable effect of methanolic and aqueous extracts against the uropathogenic bacteria reported in this study supported the traditional uses of this plant in treating UTIs. The results acquired from this investigation revealed that E. ramosissimum stem extract might be considered as an interesting candidate in the development of antibacterial agent against UTIs coupled with antioxidant properties.

Evaluating the antibacterial effect of synthesized herbal toothpastes and their efficacy for dentine tubule occlusion: Scanning electron microscopy and energy-dispersive X-ray spectroscopy analysis

The tubule occlusion of two newly developed herbal toothpastes was examined. They were prepared based on the mixture of pomegranate peel and Equisetum arvense extracts with strontium acetate. The antimicrobial activity of pomegranate peel and E. arvense were determined using minimum inhibitory concentration (MIC). Then, 30 mid-coronal dentin discs from the human third molars were etched for 30 s with the lemon juice (pH = 2.4). The specimens divided into the three groups. While the control group had 6 specimens, Groups 1 and 2 were including 12 specimens. Group 1 brushed with toothpaste containing 10% strontium acetate and 5% hydroalcoholic extracts of pomegranate peel, and Group 2 brushed with 5% strontium acetate, 5% hydroalcoholic extracts of E. arvense, and 5% hydroalcoholic extracts of pomegranate peel. Brushing was simulated for 6 months with 2 N loading. Then, 50% of discs in each group were immersed in lemon juice for 1 min. Moreover, specimens in control group were brushed with distilled water. Finally, all 30 discs were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDXS). The occluded dentin tubules were counted and statistically evaluated. It was found that the number of open dentin tubules decreases significantly after brushing with both tested toothpastes compared with control group (p < .001). Moreover, a significant difference was observed between two toothpastes before and after acid immersion process (p < .001). The SEM micrographs confirmed the dentin tubule occlusion of both herbal dentifrices. Besides, EDXS analysis approved the strontium and silica presence on the dentin tubules for the toothpaste which was based on E. arvense.

Herbal Extracts with Antifungal Activity against Candida albicans: A Systematic Review

In the era of antimicrobial resistance, fungal pathogens are not an exception. Several strategies, including antimicrobial stewardship programs and high throughput screening of new drugs, are being implemented. Several recent studies have demonstrated the effectiveness of plant compounds with antifungal activity. In this systematic review, we examine the use of natural compounds as a possible avenue to fight fungal infections produced by Candida albicans, the most common human fungal pathogen. Electronic literature searches were conducted through PubMed/MEDLINE, Cochrane, and Science Direct limited to the 5 years. A total of 131 articles were included, with 186 plants extracts evaluated. Although the majority of the natural extracts exhibited antifungal activities against C. albicans (both in vivo and in vitro), the strongest antifungal activity was obtained from Lawsonia inermis, Pelargonium graveolens, Camellia sinensis, Mentha piperita, and Citrus latifolia. The main components with proven antifungal activities were phenolic compounds such as gallic acid, thymol, and flavonoids (especially catechin), polyphenols such as tannins, terpenoids and saponins. The incorporation of nanotechnology greatly enhances the antifungal properties of these natural compounds. Further research is needed to fully characterize the composition of all herbal extracts with antifungal activity as well as the mechanisms of action of the active compounds.

Phytochemistry and Pharmacology of the Genus Equisetum (Equisetaceae): A Narrative Review of the Species with Therapeutic Potential for Kidney Diseases

The Equisetum genus, Equisetaceae family, is widely distributed worldwide and may be the oldest nonextinct genus on Earth. There are about 30 known species, which are very often used in traditional medicine with diverse applications. This review aimed to compile scientific reports about Equisetum species with relevant pharmacological properties and/or therapeutic potential for kidney diseases. Our bibliographic survey demonstrates that the most widespread traditional use of Equisetum is as a diuretic, followed by the treatment of genitourinary diseases (kidney diseases, urethritis, kidney stones, and others), inflammation, wound healing, rheumatic diseases, prostatitis, and hypertension. The most popular species from the Equisetum genus with medicinal use is E. arvense L., whose diuretic effect was confirmed in animal models and clinical trials. The species E. bogotense Kunth also demonstrated the beneficial effect of inducing diuresis in both experimental and clinical assays. Several other species have also been studied regarding their therapeutic potential, showing different biological actions. Regarding the chemical composition, it contains many active constituents, such as alkaloids, flavonoids, phenol, phytosterols, saponins, sterols, silicic acid, tannin, triterpenoids, and volatile oils. However, despite the widespread traditional use, many species need to be explored in detail for scientific validation of popular use. Indeed, the species of the Equisetum genus have great potential in the management of kidney disorders.

Antiviral and Antinematodal potentials of chitosan: Review

For many years, chemical pesticides have been performed to control different pests and diseases and this may be due to their broad spectrum of action, easy of application and the relatively low cost. But these chemicals have environmental risks, thus alternative control agents are needed. Chitosan is one of the novel suggested solutions to reduce the economic losses associated with chemical pesticides. Chitosan is naturally-occurring compound, as well as safe and biodegradable which obtained from certain natural sources. Chitosan have unique properties which help to control viruses, bacteria, fungi, insects, plant nematodes and other pests locally and systemically.

In vitro anti- biofilm and anti-bacterial activity of Sesbania grandiflora extract against Staphylococcus aureus

The main objective of this research is to investigate the anti-biofilm and anti-bacterial activity of Sesbania grandiflora (S. grandiflora) against Staphylococcus aureus. S. grandiflora extract were prepared and analyzed with UV -Vis spectroscopy, Fourier transform infrared spectroscopy, Dynamic light scattering. Biofilm forming pathogens were identified by congo-red assay. Quantification of Extracellular polymeric substance (EPS) particularly protein and carbohydrate were calculated. The efficacy of the herbal extract S. grandiflora and its inhibition against the pathogenic strain of S. aureus was also evaluated. The gradual decrease or disappearance of peaks reveals the reduction of protein and carbohydrate content in the EPS of S. aureus when treated with S. grandiflora. The antibacterial activity of S. grandiflora extract against the bacterial strain S. aureus showed that the extract were more active against the strain. To conclude, anti-biofilm and antibacterial efficacy of S. grandiflora plays a vital role over biofilm producing pathogens and act as a good source for controlling the microbial population.