Echinodorus

Echinodorus

Identity, Taxonomy, and Nomenclature

Echinodorus is a genus of semi-aquatic and emergent monocotyledonous plants belonging to the family Alismataceae. The genus comprises 27 species characterized as monocotyledons that belong to the Alismataceae family and is distributed throughout the American continent. Within the genus, two species predominate in traditional medicine and pharmacological research:

• Echinodorus grandiflorus (Cham. & Schltdl.) Micheli — the larger-flowered species, native to Brazil and widely studied for cardiovascular and anti-inflammatory effects.
• Echinodorus macrophyllus (Kunth) Micheli — synonymous with Aquarius macrophyllus (Kunth) Christenh. & Byng and Alisma macrophyllum Kunth, the large-leaved species with an almost identical ethnopharmacological profile.

The two most well-known and utilized species in Brazil, E. grandiflorus and E. macrophyllus, have similar botanical characteristics and medicinal properties.

Echinodorus macrophyllus (Kunth) Micheli (Alismataceae), known as chapéu-de-couro, chá-mineiro, erva-de-pântano, erva-de-bugre, congonha-do-brejo, and erva-do-brejo, occurs in Minas Gerais and São Paulo. The most widespread common name in Portuguese, chapéu-de-couro, translates literally to "leather hat", a reference to the plant's large, stiff, leather-textured leaves. The plant is also known in English as "leather hat."

Echinodorus macrophyllus, an aquatic plant of the family Alismataceae, known in Brazil as chapéu-de-couro, is widely used in the production of a very popular Brazilian soft drink.

Common Forms and Preparations

Leaves of E. macrophyllus have been used in folk medicine in the form of decoction, infusion, or bottled, considered a reputed remedy for the treatment of infections, respiratory diseases, inflammatory conditions, kidney dysfunctions, diuretic, anti-hypertensive, and against pains of the genito-urinary system. In addition to traditional preparations, Echinodorus macrophyllus, known in Brazil as chapéu de couro, is popular in the food industry, where it is used in teas and infusions. The plant's aerial parts — primarily the leaves — serve as the botanical drug material for both traditional and contemporary preparations. Infusion or decoctions of its aerial parts are popularly used to treat infections, renal and respiratory diseases, and acute and chronic inflammatory conditions.

Historical and Traditional Use

The use of Echinodorus species as medicinal plants is firmly rooted in Brazilian folk and indigenous medicine, and their importance has been recognized since the earliest systematic botanical surveys of the country. Although it has therapeutic and commercial importance and is described in the two first editions of the Brazilian Pharmacopoeia (1924, 1959), there are few studies that contemplate it.

Echinodorus grandiflorus (Cham. & Schltdl.) Micheli is a native Brazilian species used in traditional practices for the treatment of several conditions such as inflammatory diseases, arthritis, and hypertension. A wide range of additional conditions were also addressed through traditional use: its leaves are resources for very common teas, used as diuretic and anti-inflammatory, blood depurative, against arthritis and skin diseases, liver maladies and renal affections, as well as against amygdalitis, pharyngitis, stomatitis, and gingivitis.

Traditionally, this plant has been used as diuretic, hypotensive, in the prevention of arteriosclerosis, depurative, anti-inflammatory, and analgesic. The infusion of its leaves has been used as an antihypertensive and diuretic agent by different native populations in South America for many years.

Reflecting its long ethnobotanical history, due to its extensive ethnobotanical use in Brazil, the genus Echinodorus was included as a hypolipidemic and diuretic agent according to the herbal form of the Brazilian Pharmacopoeia. This official recognition formalized what had already been deeply embedded in Brazilian popular medicine for generations.

Regulatory and Pharmacopeial Status

Both principal medicinal species hold formal recognition within the Brazilian regulatory system. E. macrophyllus is listed as a priority species for the development of herbal preparations for the Brazilian Unified Health System (SUS) and is included in the 1st Edition of the Herbal Medicines Formulary of the Brazilian Pharmacopoeia (Brazil, Ministry of Health, 2011). Echinodorus macrophyllus (Kunth) Micheli, known as chapéu-de-couro, belongs to the Alismataceae family and is listed in the Brazilian Pharmacopoeia (2010).

Echinodorus macrophyllus (Kunth) Micheli (Alismataceae) is vulgarly known as chapéu-de-couro and is listed in the Brazilian Pharmacopoeia; the leaves are popularly prepared as an infusion and used as a diuretic and to treat inflammatory conditions.

Key Phytochemical Constituents and Active Compounds

Both E. grandiflorus and E. macrophyllus share a complex and overlapping phytochemical profile. The body of literature reports that the chemical composition of crude E. grandiflorus extracts are notably composed of diterpenoids and flavonoids metabolites. More detailed profiling has identified a broader array of compound classes.

Diterpenoids

Diterpenoids represent one of the most structurally distinctive classes of secondary metabolites in Echinodorus. A new seco-labdane-type diterpenoid, chapecoderin A (1), and two new rearranged labdane-type diterpenoids, chapecoderins B (2) and C (3), were isolated from the leaves of the Brazilian medicinal plant Echinodorus macrophyllus (chapéu-de-couro), and their structures and relative stereochemistry were elucidated by spectroscopic data. Chapecoderins A–C (1–3) possess in common an alpha,beta-unsaturated gamma-lactone ring in the side chain. Other diterpenoid types reported from the genus include cembrane diterpenoids (echinodolides A and B, which contain an eight-membered lactone ring).

Flavonoids and Flavonoid Glycosides

Flavonoids constitute a central pharmacologically active fraction. Analysis by HPLC-ESI-MS-Q-TOF showed that the flavonoid-rich fraction (Fr40) exhibited as main components swertisin (37.4%) and swertiajaponin (35.79%), besides isoorientin 7,3′-dimethyl ether (9.29%), swertisin-O-rhamnoside (7.86%), isoorientin (5.42%), isovitexin (2.07%), isovitexin-O-rhamnoside (1.21%), and isovitexin-7-O-glucoside (1.02%).

Flavonoids such as isoorientin, isovitexin, swertiajaponin, swertisin, and chicoric, caffeic, and ferulic phenolic acids were described in leaves of E. grandiflorus.

Hydroxycinnamoyl Tartaric Acid Derivatives and Organic Acids

The flavonoids homoorientin and swertisin, along with the hydroxycinnamoyl tartaric acid derivatives chicoric acid, caffeoyl-feruloyl-tartaric acid, and di-feruloyl-tartaric acid, have been proposed as chemical markers for the species, in addition to cis- and trans-aconitic acids. The contents of cis- and trans-aconitic acid, homoorientin, chicoric acid, swertisin, caffeoyl-feruloyl-tartaric acid, and di-feruloyl-tartaric acid were quantified by UPLC-DAD in various hydroethanolic extracts from the leaves.

Additional Compound Classes

A phytochemical characterization of species from the Alismataceae family prevalent in Brazil demonstrated the presence of diterpenes and phenolic derivatives, as well as alkaloids, organic acids, glycosides, tannins, triterpenes, and steroids. Specifically for E. grandiflorus, the species has been shown to contain several fatty acids, diterpenoids, phenolic acids, flavonols, alkaloids, saponins, and tannins.

Phytochemical analysis with E. macrophyllus leaves revealed the presence of triterpenoids, steroids, flavones, flavonols, and xanthones.

The phytochemistry of this species shows in the literature the presence of polyphenols, flavonoids, diterpenes, and sesquiterpenes.

Currently, the main chemical constituents present in the species are known; many diterpenoids, alkaloids, saponins, and tannins have been identified.

Mechanisms of Action

Anti-Inflammatory Mechanisms

Multiple mechanisms have been identified by which Echinodorus extracts and their constituent fractions reduce inflammation. Hydroxycinnamoyl derivatives present in SF1 (a sub-fraction of E. macrophyllus fractions) are related to crucial anti-inflammatory mechanisms, decreasing the levels of TNF-α, IL-1β, CKCL1/KC, LTB4, and PGE2 in the exudate.

Anti-inflammatory action was evaluated in vivo by air-pouch model (total leucocyte, protein, and leukotriene B4 [LTB4]), and in vitro by neutrophil migration (transwell assay) and its Mac1 expression (flow cytometry), and RAW 264.7 nitric oxide (NO) production (Griess reaction). Fr20 reduced total leucocyte at 2.5 mg/kg (29.7%), while the ethanolic extract of E. macrophyllus (EAEm) increased it (94.0%). Fr20 showed higher (P < 0.05) inhibition (89.8%) of LTB4 in exudate than EAEm (75.0%).

The flavonoid-rich fraction elicited the most potent inhibition of tumor necrosis factor (TNF) release by lipopolysaccharide (LPS)-stimulated THP-1 cells, along with its constituents isovitexin and isoorientin. Other classes of metabolites present in these species, such as diterpenes, hydroxycinnamoyl tartaric acid derivatives, and cis- and trans-aconitic acid, have also been reported for their anti-inflammatory activity by inhibiting TNF release in LPS-stimulated THP-1 cells.

Polynomial regression analysis showed the association between the contents of swertiajaponin, swertisin, trans-aconitic, and chicoric acids with the antitumor necrosis factor-α activity of the extracts and fractions.

Antinociceptive (Analgesic) Mechanisms

The analgesic activity of E. macrophyllus involves both peripheral and central pathways. The results suggest central, peripheral, or both antinociceptive responses; Fr40, a flavonoid-rich fraction, did not act via the opioid pathway, nor by activation of guanylate cyclase; instead, the involvement of adrenergic activation and NO pathways was demonstrated.

Isoorientin decreased NO and tumor necrosis factor-alfa production by RAW 264.7 cells. Swertisin and 2-O-rhamnosyl-swertisin were effective in inhibiting the hypernociceptive response induced by carrageenan. Isovitexin (apigenin-6-C-glucoside) exhibits several pharmacological properties including antioxidant, anti-inflammatory, anti-hyperalgesic, and neuroprotective ones.

Antihypertensive and Vasodilatory Mechanisms

EEEG (crude ethanolic extract of E. grandiflorus) and its butanolic fraction have important vasodilatory effects mediated by endothelial M3-muscarinic and B2-bradykininergic receptors, inducing nitric oxide and prostacyclin release followed by K⁺ channel activation in the vascular smooth muscle.

The blockade of nitric oxide synthesis significantly reduced the hypotension induced by intravenous administration of EEEG. Moreover, pre-treatment of the animals with a selective antagonist of cholinergic muscarinic receptors or of platelet-activating factor (PAF) receptors partially blunted the cardiovascular effects of EEEG.

Immunosuppressive Mechanisms

The effects of the aqueous extract of E. macrophyllus (AEEm) on immune cell functions, proliferation, and nitric oxide production were evaluated. Mice treated orally for 7 days with AEEm had inhibited B cell antibody production (0.5 mg/kg b.w.) and delayed-type hypersensitivity (0.5 and 5 mg/kg b.w.) mediated by T cells, reducing subcutaneous tissue leukocyte infiltration. AEEm inhibited, in vitro, NO production by stimulating J774 cells in a dose-dependent manner, with no cytotoxicity.

Lipase Inhibition

Previous studies indicated properties to inhibit lipase activity by the methanol extract of E. grandiflorus leaves. Flavonoids such as isoorientin and isovitexin inhibit lipase activity, which justifies the pancreatic lipase inhibitory activity of E. grandiflorus EtOH extract.

Antioxidant Properties

Secondary metabolites, mainly flavonoids and their glycosylated derivatives, have been associated with hypolipidemic, antioxidant, and anti-nitrosative properties, which can modulate local inflammatory processes, assisting in the fight against diseases such as atherosclerosis.

Scientific Evidence by Area of Use

1. Inflammation and Rheumatic Disease

The anti-inflammatory profile of Echinodorus is the most extensively researched area of its pharmacology, though all evidence to date derives from preclinical (in vitro and animal) studies. No controlled human clinical trials have been published.

Both Echinodorus macrophyllus and Echinodorus grandiflorus are plants traditionally used in Brazil to treat rheumatism and arthritis, whose anti-inflammatory effects are supported by scientific evidence.

The anti-inflammatory and antiedematogenic activity of hydroethanolic extracts of E. macrophyllus leaves have been demonstrated in mouse paw edema induced by different inflammatory agents. A 2024 study published in ScienceDirect investigated the development of standardized extracts specifically for arthritis: the standardized 70% EtOH and 50% EtOH extracts from the aerial parts of E. macrophyllus, which contain higher levels of chemical markers, exhibit potent anti-inflammatory activity and reduce proteoglycan degradation; these extracts are potentially useful for developing herbal preparations to manage arthritic conditions and should be prioritized for further studies.

Pharmacological studies have shown that oral treatments using the hydroalcoholic extracts of leaves from this plant have significant anti-inflammatory, anti-hypertensive, diuretic, and cardioprotective effects in rats with no toxicity.

Strength of evidence: All anti-inflammatory and anti-arthritic evidence is preclinical (animal models and cell-based assays). No human or clinical trial data were found. The body of preclinical evidence is internally consistent but cannot be extrapolated to clinical efficacy without controlled human studies.

2. Pain (Antinociception)

A series of experiments in rodent models has established dose-dependent antinociceptive activity for both the aqueous extract and its fractionated preparations.

There was a reduction in xylene-edema index with Fr40 (25 mg/kg), AEEm (50 mg/kg), and Fr20 (50 mg/kg). All doses of AEEm, Fr20, and Fr40 reduced both phases of the formalin model.

This work demonstrated the antinociceptive effects of E. macrophyllus leaves infusion, as it is popularly used; its fractionation resulted in the Fr40 fraction with higher antinociceptive activity than traditional analgesic drugs.

Strength of evidence: Preclinical (murine models) only. Evidence is internally consistent across multiple experimental pain models, but no human data exist.

3. Hypertension and Cardiovascular Effects

The antihypertensive action of a crude ethanolic extract (EEEG) from leaves of Echinodorus grandiflorus (Alismataceae) was investigated in spontaneously hypertensive rats; the intraperitoneal injection of increasing doses of EEEG (300–1000 mg/kg) elicited dose-dependent reductions in mean arterial pressure. Specifically, the intraperitoneal injection of increasing doses of EEEG (300–1000 mg/kg) elicited dose-dependent reductions in mean arterial pressure (MAP) that were paralleled by reductions of cardiac output and systemic vascular resistance, reaching the maximum of 23 ± 5%, 13 ± 3%, and 18 ± 4%, respectively. Comparable reductions of MAP were obtained upon intravenous administration of EEEG (3–100 mg/kg), reaching the maximum decrease of 51 ± 6% (P < 0.001).

Prando et al. reported that the ethanolic extract of E. grandiflorus causes a hypotensive as well as antihypertensive effect in a renovascular rat model of hypertension, two-kidney-one-clip (2K-1C).

Water, Na⁺, Cl⁻, and Na⁺ excretion rates were significantly increased by the ethanol-soluble fraction of E. grandiflorus (ES-EG), while urinary bicarbonate excretion was reduced. Moreover, ES-EG was able to significantly increase renal blood flow and reduce mean arterial pressure and oxidative stress in in vitro and in vivo models. The results showed that ES-EG has significant diuretic and hypotensive activity, and these effects could be related to an important renal and systemic vasodilator effect.

Strength of evidence: Entirely preclinical. Multiple independent rodent studies report consistent antihypertensive and vasodilatory effects, but the clinical relevance for human hypertension management is unestablished.

4. Diuretic Activity

The oral administration of an extract of E. grandiflorus leaves induced diuresis in rats. This observation is consistent with the plant's longstanding traditional use as a diuretic. Several preclinical pharmacological studies have presented E. grandiflorus as a promising species for the treatment of cardiovascular diseases; available data have shown that different preparations obtained from the species could present diuretic, antiedematous, antihypertensive, and vasodilatory effects.

Strength of evidence: Preclinical only. No controlled human data available.

5. Lipid Modulation and Atherosclerosis

Echinodorus grandiflorus is an important medicinal plant species native to South America; despite extensive popular usage as a hypolipidemic drug, its effects as an atheroprotective agent were previously unknown. A study evaluated the effects of an ethanol-soluble fraction obtained from E. grandiflorus (ESEG) leaves against the development of atherosclerosis in rabbits. In this animal study, male rabbits received a diet supplemented with 1% cholesterol (cholesterol-rich diet [CRD]) for 60 days; after 30 days of the CRD, the animals were divided into five groups (n = 6) and treated with ESEG (10, 30, and 100 mg/kg), simvastatin (2.5 mg/kg), or vehicle once daily for 30 days. The negative control group was fed a cholesterol-free diet and treated orally with vehicle.

Regarding mechanisms, the EtOH extract of E. grandiflorus inhibited lipase with an IC50 of 115.8 ± 57.1 μg/mL.

Strength of evidence: Preclinical (animal model). No human lipid or cardiovascular outcome trials have been identified.

6. Immunomodulatory Effects

Immunosuppressive effects have been demonstrated for the first time in aqueous extract studies. This immunosuppressive effect supports a potential therapeutic use of AEEm to control exacerbated humoral and/or cellular immune response, as in autoimmune rheumatic diseases.

An aqueous extract of E. macrophyllus is used to treat rheumatic diseases that are usually characterized by exacerbated T and B lymphocyte responses; Pinto et al. (2007) observed immunosuppression of the T-cell response in mice treated orally with chapéu-de-couro extract for 7 days.

Strength of evidence: Preclinical (murine immunology models). The immunosuppressive property is noteworthy in the context of safety (see below) as well as therapeutic potential.

7. Antiviral Activity

A preliminary in vitro screen identified antiviral potential against Zika virus (ZIKV). In a screening of 37 plant extracts tested in vitro against Vero cells infected with ZIKV, significant anti-ZIKV activity was elicited by the extract of Echinodorus grandiflorus (1.7 log of inhibition). The anti-Zika virus activity of E. grandiflorus is significant in infected SH-SY5Y neuronal cells, as it was able to reduce the viral load and cell death while maintaining cell viability.

Strength of evidence: In vitro screening only. No animal or human data on antiviral activity have been identified. This is a preliminary and exploratory finding.

8. Antimicrobial Activity

Some pharmacological activities have been observed in vivo, such as antimicrobial effects; in vitro activities also confirmed, such as trypanocidal, leishmanicidal, and antineoplastic properties. These are reported as preclinical observations only, with no clinical data available.

Strength of evidence: Preliminary in vitro and animal data. Clinical relevance is undetermined.

Dosage Forms and Doses Reported in Studies

The following dosages are drawn exclusively from the sources cited above and reflect doses used in preclinical studies, not established human clinical recommendations.

• Aqueous extract (AEEm), oral, antinociception (mice): AEEm at 50 mg/kg, Fr20 at 50 mg/kg, and Fr40 at 25 mg/kg resulted in reduction of xylene-edema index; all doses of AEEm, Fr20, and Fr40 reduced both phases of the formalin model.
• Aqueous extract (AEEm), oral, immunosuppression (mice): Mice treated orally for 7 days with AEEm had inhibited B cell antibody production (0.5 mg/kg b.w.) and delayed-type hypersensitivity (0.5 and 5 mg/kg b.w.) mediated by T cells.
• Crude ethanolic extract (EEEG), intraperitoneal, antihypertensive (spontaneously hypertensive rats): The intraperitoneal injection of increasing doses of EEEG (300–1000 mg/kg) elicited dose-dependent reductions in mean arterial pressure, cardiac output, and systemic vascular resistance.
• Crude ethanolic extract (EEEG), intravenous, antihypertensive: Intravenous administration of EEEG (3–100 mg/kg) reached a maximum decrease of 51 ± 6% in mean arterial pressure.
• ESEG (ethanol-soluble fraction), oral, atherosclerosis (rabbits): Male rabbits received a 1% cholesterol diet for 60 days; after 30 days, animals received ESEG at 10, 30, and 100 mg/kg once daily for 30 days.
• Aqueous extract, oral, reproductive toxicity (pregnant rats): Animals were treated with 250, 500, and 1,000 mg/kg/day by gavage for 15 consecutive days, remaining during mating and until the 14th day of gestation.
• Standardized hydroethanolic extracts (aerial parts), anti-arthritis: Extracts were prepared through percolation with 96°GL ethanol and hydroethanolic solutions at 90%, 70%, and 50% (v/v).

No standardized human clinical dosage has been established for any Echinodorus preparation, and the above doses all reflect preclinical protocols.

Body Systems and Health Areas Associated with Echinodorus

Based on the totality of the preclinical literature, Echinodorus species are associated with effects on the following body systems:

• Musculoskeletal system: Anti-inflammatory and antiedematogenic effects relevant to rheumatism, arthritis, and joint inflammation.
• Cardiovascular system: Antihypertensive, vasodilatory, cardioprotective, and potential lipid-lowering/antiatherosclerotic effects.
• Renal system: Diuretic activity with increased water and electrolyte excretion.
• Immune system: Immunomodulatory (immunosuppressive) activity, particularly on T and B lymphocyte function.
• Nervous system (pain pathways): Antinociceptive properties acting on peripheral and central mechanisms.
• Hepatic and metabolic: Lipase inhibition and potential hypolipidemic/cholesterol-reducing activity.

Safety Considerations

Genotoxicity and Mutagenicity

This is the most significant documented safety concern for Echinodorus. In bacterial assays based on the induction of SOS functions examining the genotoxicity and mutagenicity of an aqueous extract of E. macrophyllus leaves, the whole extract and an ethyl acetate fraction showed similar genotoxicity and caused an approximately 70-fold increase in lysogenic induction; the extract also gave a positive result in the SOS chromotest with an increase of 12-fold in β-galactosidase enzymatic units. The results obtained indicate that the extract has marked genotoxic and mutagenic effects that are clearly associated with structural alterations in purine targets. There was a strong trend towards base substitutions and frameshifts at purine sites in the mutations induced by the extract in Escherichia coli (CC103 and CC104 strains) and Salmonella typhimurium test strains (22-fold increase in histidine revertants in TA98 strain).

Lopes et al. (2000) observed DNA damage in kidney cells of Swiss mice treated with E. macrophyllus, and suggest that this result occurs by the presence of substances with potential genotoxic effects against the cells of this organ.

Hepatotoxicity Signals

Lopes et al. (2000) evaluated the toxicity of E. macrophyllus in Swiss male mice and did not observe changes in liver weight, but observed a modest increase in transaminase, which could be evidence of hepatotoxicity. Animals in the T-1000 group showed histopathological changes suggestive of chronic inflammation in the liver, kidneys, and spleen. The hepatic lesions observed are compatible with the laboratory findings, including the increase in AST.

Reproductive Toxicity

A dedicated study examined the safety of E. grandiflorus in pregnancy. To evaluate the possible toxicity of the aqueous extract of Echinodorus grandiflorus in pregnant rats, animals were distributed in groups treated with 250, 500, and 1,000 mg/kg/day by gavage, and a control group received saline solution; treatment was carried out for 15 consecutive days, remaining during mating and until the 14th day of gestation, after which pregnant animals were euthanized by exsanguination under anesthesia.

Immunosuppression as a Safety Concern

The immunosuppressive activity documented for E. macrophyllus extracts carries safety implications beyond potential therapeutic benefit. Aqueous extract of Echinodorus macrophyllus (AEEm) effects on immune cell functions, proliferation, and nitric oxide production were evaluated in a controlled animal experiment. This property could theoretically increase susceptibility to infection or reduce vaccine responses, though these effects have not been studied in humans.

Toxicological Knowledge Gaps

Limited studies have evaluated the toxicological aspects of this species, and further chronic toxicological investigations are needed to establish the risks of excessive ingestion of preparations from this plant. In the literature there are few studies on the toxicological potential of chapéu-de-couro, with preliminary toxicological investigations performed only for E. macrophyllus, and another evaluating the cytotoxicity and genotoxicity of the extract, but until the moment no research in the literature was found to evaluate reproductive toxicity of Echinodorus comprehensively.

Acute Toxicology of Sub-Fractions

Hydroxycinnamoyl derivatives present in SF1 (a sub-fraction of E. macrophyllus) showed higher anti-inflammatory properties. A study describing the acute toxicological effect of SF1 subfraction on SW mice treated orally for five days in the air-pouch model evaluated hematological and biochemical determinations on blood samples; the relative organ weight and its histopathological analysis; the liver genotoxicity assessment; and the activity of liver enzymes from xenobiotic metabolism.

Summary of Evidence and Research Status

Through systematic review of the accumulated knowledge about E. grandiflorus, the botanical, phytochemical, ethnobotanical, and pharmacological properties of this medicinal plant demonstrate its potential to naturally provide anti-inflammatory and anti-oxidant effects with a special emphasis on anti-hypertensive and cardioprotective effects. However, the overall state of the evidence requires honest characterization:

• All pharmacological evidence for Echinodorus species is currently preclinical (in vitro and animal studies). No controlled human clinical trials establishing efficacy or safety for any indication have been published.
• Preclinical anti-inflammatory, antinociceptive, antihypertensive, diuretic, and immunomodulatory findings are internally consistent across multiple independent research groups, lending biological plausibility to the traditional uses.
• Significant safety signals — notably genotoxicity in bacterial assays and hepatotoxic signals in rodents — remain to be resolved by further chronic toxicology and human safety studies.
• The goal of ongoing research is to define a standardized extract suitable for future scientific validation and clinical use.
• Scientific evidence has observed anti-inflammatory properties of E. grandiflorus extracts in experimental models of acute inflammation, as well as its efficacy as diuretic, analgesic, vasodilator, and in reducing cholesterol levels in experimental models; however, studies in experimental models more suitable for human disease remain needed.

References

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