Nut grass

Nut Grass (Cyperus rotundus L.): A Comprehensive Encyclopedic Reference

1. Identity: Botanical Classification, Common Names, and Natural Source

Cyperus rotundus L., also known as purple nutsedge or nutgrass or java grass, belongs to the sedge family, Cyperaceae. It is the third largest family of monocotyledonous plants, and the species itself is a colonial, perennial herb, 7–40 cm tall with fibrous roots that reproduces largely by rhizome and tubers. It is an erect, glabrous, grass-like, fibrous-rooted, herbaceous plant with slender, scaly creeping rhizomes, widely distributed in temperate, tropical, and sub-tropical regions.

Mature individual tubers are dark reddish-brown, about 12 mm thick and vary from 10 to 35 mm long. The leaves are dark green, shiny, narrow, and grass-like ranging in size from 5 to 12 mm wide to 50 cm long. The upright culms or stems support a much-branched inflorescence with bisexual flowers with three stamens and a pistil bearing three stigmas.

Popularly called "the world's worst weed," Cyperus rotundus has attracted particular attention as a medicinal plant due to its broad spectrum of pharmacological activities. Currently, it is one of the most widespread, problematic, and economically damaging agronomic weeds, growing wildly in various tropical and subtropical regions of the world.

The plant is known under numerous names across cultures and medical traditions:

• Sanskrit/Ayurveda: Musta, Mustaka, Nagarmotha, Motha, Mutha
• Traditional Chinese Medicine (TCM): Xiang Fu (香附), Rhizoma Cyperi
• Common English names: Nut grass, Purple nutsedge, Coco grass, Java grass, Nut sedge

This is the most investigated plant worldwide due to the higher concentration of active ingredients in the form of essential oils, phenolic acids, ascorbic acids, and flavonoids in the tuber and rhizomes.

Common Forms and Preparations

The medicinal part used across virtually all traditions is the rhizome (underground stem) and attached tubers, known pharmacopoeially as Rhizoma Cyperi. The rhizome has been used for perfume and spice and Ayurvedic therapy in Arab countries, Africa, and India for centuries, while the leaves are widely used to flavor food, especially in the Middle East and Southeast Asia.

Preparations documented in ethnobotanical and pharmacological literature include:

• Decoctions and water extracts: Dried, sliced rhizomes boiled in water, the most common traditional form.
• Hydroalcoholic (ethanolic/methanolic) extracts: The form most frequently used in modern pharmacological studies.
• Essential oil: Obtained by steam distillation of the rhizome; used in aromatherapy and as a subject of preclinical research.
• Powders: Dried, ground rhizome incorporated into Ayurvedic formulas.
• Processed forms in TCM: In Chinese medicine, Xiang Fu can be prepared in several ways; most commonly it is dry-fried before being included in a prescription, but it can also be soaked in vinegar or wine.

2. Traditional and Historical Use

Ayurveda (India)

The nutgrass, Cyperus rotundus L. (Family: Cyperaceae), is a colonial, perennial herb considered to have originated in India 2,000 years ago and has been widely used in Ayurveda to treat several ailments. It is known as "Musta" in Ayurveda, India's ancient medical system, and is appreciated for its digestive and anti-inflammatory effects.

In India, Ayurveda uses C. rotundus, also known as "Motha" and "Mutha," for the treatment of diarrhea, dysentery, diabetes, arthritis, leprosy, bronchitis, amenorrhea, dysmenorrhea, fever, and blood disorders. The rhizomes are said to have astringent, diaphoretic, analgesic, aromatic, antispasmodic, carminative, antibacterial, antimalarial, antioxidant, antiplatelet, hepatoprotective, and diuretic qualities in Ayurveda. The plant also finds mention in ancient Ayurvedic literature as a drug capable of reducing adipose tissue, reflecting a historical awareness of its potential metabolic effects.

Traditional Chinese Medicine (TCM)

In traditional Chinese medicine (TCM), C. rotundus has been widely used in the treatment and prevention of numerous diseases in traditional systems of medicine around the world, including nervous and gastrointestinal system diseases and inflammation. Its rhizomes are frequently used to treat liver disease, stomach pain, breast tenderness, dysmenorrhea, and menstrual irregularities.

This herb was first recorded during the Later Han Period, around the middle of the 10th century C.E. It is now still a commonly used herb in clinical Chinese medical practice. In both Taiwan and China, Xiang Fu is one of the most commonly prescribed herbs for treatment of dysmenorrhea.

In the TCM literature Compendium of Materia Medica, Cyperus rotundus is used to treat Han Ning Qi Zhi (qi stagnation due to cold congealing), which is a common cause of limb pain.

Classical TCM prescribing involves combining Xiang Fu with other herbs in formulas. For cases in which gastric symptoms are more apparent, it is often added to formulas such as Xiang Fu San (香附散), wherein it is combined with cooling herbs. Such compound formulas are intended to control stomach acid, relieve inflammation, suppress nausea, and alleviate epigastric and flank pain.

Western Asian, Egyptian, and African Traditions

In West Asia, C. rotundus is applied in folk medicine for the treatment of leprosy, fever, thirst, and blood illnesses. In Egyptian folk medicine, it is used for expelling evil, strengthening yang, diuresis, sedation, expelling wind, stimulation and nourishing, and for the treatment of renal colic and stomach pain. In Egypt, C. rotundus is used in traditional medicine as an anthelmintic, aphrodisiac, diuretic, sedative, carminative, stimulant, and tonic, and for treating renal colic and stomach pains.

Other Regional Uses

Historically, this herb has been employed in traditional medicinal practices across China, India, Africa, Japan, and Arab nations to treat various ailments. In Tunisian folkloric medicine, C. rotundus is used to treat stomach disorders and inflammatory diseases.

3. Key Constituents and Active Compounds

In the past six decades, about 192 natural products have been isolated and characterized from this plant species. Among them, terpenoids and flavonoids are the major bioactive constituents, mostly harvested from Asia and Africa. A more comprehensive 2023 PMC review identified an even larger chemical inventory.

Phytochemical studies have shown that C. rotundus (Cyperi Rhizoma) contains volatile oil, flavonoids, triterpenes, sterols, alkaloids, sugars, trace elements, and other components.

Sesquiterpenoids (Primary Volatiles)

Sesquiterpenoids are the dominant and most pharmacologically active class of compounds in C. rotundus, concentrated in the essential oil of the rhizome.

• α-Cyperone: A sesquiterpene ketone and the major bioactive constituent of the essential oil. It is present in very high concentrations and has been studied for its anti-inflammatory, analgesic, and neuroprotective properties.
• Cyperotundone, Cyperene (cyperene-1 and cyperene-2): Cyperenone, α-cyperone, β-selinene, cyperene-1, cyperene-2, and oxidoeudesm-11-en-3α-ol are among the main sesquiterpene constituents.
• Additional sesquiterpenoids: The rhizome also contains copadiene, epoxyguaiene, rotundone, cyperenol, cyperolone, eugenol, cyperol, isocyperol, α- and β-rotunol, copaene, mustakone, kobusone, isokobusone, patchoulenone, sugetriol triacetate, rotundenol, rotundene, and β-sitosterol, among others.
• Nootkatone and valencene: Several reports have stated the presence of sesquiterpenes, such as valencene and nootkatone, in the rhizomes of this plant.

Flavonoids

The ethanolic extracts of C. rotundus were determined using HPLC and reported to contain two bioactive phenolics: quercetin and chlorogenic acid. HPLC-DAD analysis has further identified quercetin (47.8%), luteolin glucoside (17%), luteolin (7.56%), apigenin-7-glucoside (6.29%), naringinin (4.52%), and other flavonoids in rhizome extracts. Furochromones, sterols, and triterpenes are also reported in the rhizomes.

Stilbenoids

Scirpusin A and Scirpusin B are stilbenoid-class compounds found in the rhizome. Scirpusins A–B, obtained from the 80% EtOH extract of C. rotundus rhizomes using bioactivity-guided fractionation, have been shown to provide in vitro protection against neurotoxins for neuronal cells.

Phenylpropanoids and Phenolic Acids

A total of at least 15 phenylpropanoids have been isolated or characterized from C. rotundus, comprising simple phenylpropanoids, coumarins, and lignans. Among them, p-coumaric acid, caffeic acid, (-)-(E)-caffeoylmalic acid, and chlorogenic acid exhibit significant antioxidant activities.

Triterpenes and Sterols

The rhizome also contains glycerol and fatty acids such as oleic, myristic, stearic, linolenic, and linoleic acids.

Other Constituents

Cyperus rotundus includes a variety of bioactive substances, including proteins, amino acids, starch, carbohydrates, flavonoids, tannins, and terpenoids. Phytochemical investigations of rhizomes have also revealed the presence of polyphenol, flavonol glycoside, saponin, Vitamin C, sesquiterpenoids, and essential oil.

4. Established Mechanisms of Action

Anti-Inflammatory Pathways

Research using methanol extracts from C. rotundus rhizomes revealed that cyperalin A has high anti-inflammatory activity through inhibition of prostaglandin E2 (PGE-2), cyclooxygenase-2 (COX-2), and arachidonate 5-lipoxygenase (LOX-5). At the compound level, α-cyperone, isolated from the rhizomes of Cyperus rotundus, inhibits LPS-induced COX-2 expression and PGE2 production through the negative regulation of NFκB signalling in RAW 264.7 cells. Additionally, α-cyperone suppresses LPS-induced COX-2 expression in RAW264.7 cells, inhibiting the production and mRNA expression of IL-6, an inflammatory cytokine.

Analgesic Mechanisms

Essential oils of C. rotundus were found to inhibit both neurogenic and inflammatory pain at higher doses, whereas at lower doses only inflammatory pain was inhibited, demonstrating analgesic activity with at least two distinct pain-pathway components. Aqueous and other extracts reduced the number of abdominal contractions caused by acetic acid in mice, revealing peripheral analgesic activity.

Antidiabetic and Anti-Obesity Mechanisms

In vitro experiments demonstrated that C. rotundus rhizome extract (CrE) effectively inhibited key digestive enzymes associated with obesity and type 2 diabetes, such as DPP-4, PTP1B, lipase, and α-amylase, with respective IC50 values of approximately 23, 51, 83, and 67 μg/mL. In diabetic rats, CrE administration suppressed glycogen phosphorylase (GP) and stimulated glycogen synthase (GS) activities by 45% and 30% respectively, increasing liver glycogen content by 45%. Five natural α-glucosidase inhibitors — cyperusphenol A, mesocyperusphenol A, cyperusphenol D, scirpusin A, and scirpusin B — have been identified from C. rotundus extracts using immobilized enzyme technique in combination with UHPLC-QTOF MS analysis.

Neuroprotective Mechanisms

Administration of C. rotundus and its metabolite α-cyperone has been studied for its capacity to prevent and suppress neuropathic pain by modulating the norepinephrine (NE) analgesic system.

Gynecological / Spasmolytic Mechanisms

Crude extract of C. rotundus has been shown to exhibit dose-dependent spasmolytic effects on rabbit jejunum, bronchodilator activity on trachea preparations, and vasodilator effects on aorta preparations, all through calcium channel blockade.

Anti-Endometriotic Mechanisms

Cyperi rhizoma extract (CRE) inhibited the adhesion of human endometriotic 12Z cells to peritoneal mesothelial Met5A cells, downregulated the mRNA expression of adhesion molecules P-cadherin and MMP-2, and significantly inhibited the mRNA expression of neurotrophins including BDNF, NGF, NT-3, and NT-4/5 in 12Z cells.

5. Scientific Evidence by Area of Use

Important note on evidence levels: The overwhelming majority of pharmacological research on C. rotundus is preclinical — conducted in cell cultures (in vitro) and animal models (in vivo, primarily rodents). Human clinical evidence is sparse, and where it exists, trials are generally small, pilot, or short-term. Current preclinical investigations predominantly utilize crude aqueous or ethanolic extracts characterized by chemical heterogeneity and a lack of quantified quality markers. Rigorous randomized controlled trials (RCTs) remain scarce, as standardized investigations into metabolic disorders are only recently emerging, thereby limiting the clinical generalizability of current findings.

5.1 Inflammation and Pain

Preclinical evidence: In the past decade, numerous studies have confirmed analgesic, anti-inflammatory, anti-pyretic, and anti-arthritic activities of C. rotundus and its chemical constituents. Anti-inflammatory activity has been demonstrated through inhibition of PGE-2, COX-2, LOX-5, and NF-κB pathways. The analgesic activity operates through both central (neurogenic) and peripheral pathways.

In murine studies, tested extracts significantly enhanced lymphocyte proliferation at 1 mg/mL, and it appears that C. rotundus extracts contain potent components such as flavonoids that may potentially be useful for modulating immune cell functions, provoking analgesic, anti-inflammatory, and antioxidant effects.

Clinical evidence: Formal randomized clinical trials specifically evaluating C. rotundus as a standalone intervention for pain or inflammation in humans are not well-established in the indexed literature reviewed here. The exact mechanism of action is not very clear and requires further evaluation.

Strength of evidence: Preclinical evidence is moderately strong across multiple models and extraction methods. Human clinical evidence is insufficient to support specific therapeutic claims at this stage.

5.2 Gynecological Conditions: Dysmenorrhea and Menstrual Disorders

In Chinese medicine, C. rotundus is prescribed for gynecological disorders, including dysmenorrhea and irregular menstruation, while its rhizomes have been used as sedatives and analgesics. In both Taiwan and China, Xiang Fu is one of the most commonly prescribed herbs for treatment of dysmenorrhea.

Preclinical evidence: Essential oil of C. rotundus (EOC) and its fractions F2–F6 significantly reduced uterine distortion times after intraperitoneal oxytocin injection, with fraction F4 — containing spathulenol, β-caryophyllene oxide, and isoaromadendrene oxide — performing best, demonstrating significant anti-dysmenorrhea activity in animal models.

Cell/molecular evidence: In vitro research has investigated CRE on cell adhesion and pain-related neurotrophin expression in endometriotic cells, finding that CRE inhibited the adhesion of human endometriotic 12Z cells to peritoneal mesothelial cells and downregulated mRNA expression of adhesion molecules and multiple neurotrophins.

Clinical evidence: Standardized investigations into primary dysmenorrhea are only recently emerging, limiting clinical generalizability. This remains an active area of TCM clinical investigation, but large-scale RCTs are lacking.

Strength of evidence: Ethnobotanical use is strong and cross-cultural. Preclinical and mechanistic data are supportive. Robust human clinical evidence is currently insufficient.

5.3 Diabetes and Glycemic Regulation

Preclinical evidence: In vitro experiments demonstrated that CrE effectively inhibited key enzymes associated with obesity and type 2 diabetes (DPP-4, PTP1B, lipase, α-amylase) and exhibited protective effects on pancreatic β-cells by inhibiting oxidative stress biomarkers and inducing antioxidant enzyme activities.

CrE significantly inhibited activities of intestinal, pancreatic, and serum lipase and α-amylase. In diabetic rats, it suppressed glycogen phosphorylase while stimulating glycogen synthase, increasing liver glycogen content by 45%.

Clinical evidence: Human clinical trials specifically targeting glycemic control with isolated C. rotundus preparations are not well-represented in the indexed peer-reviewed literature as of the time of this article's sources. Modern pharmacological studies have shown that C. rotundus possesses a hypoglycemic effect, among other biological activities.

Strength of evidence: Preclinical evidence (in vitro and animal) is consistent and mechanistically plausible. No high-quality human RCT evidence is available to confirm clinical antidiabetic efficacy.

5.4 Obesity

Preclinical evidence: Multiple rodent studies have demonstrated anti-obesity effects of aqueous and methanolic rhizome extracts in high-fat diet models.

Human clinical evidence (pilot): A standardized C. rotundus rhizome extract (CRE) containing piceatannol, scirpusin A, and scirpusin B (5% total stilbenoids) was evaluated in 30 obese individuals with a BMI of 30 to 40 kg/m² for 90 days in a randomized, double-blind, parallel-group, placebo-controlled study, with the mechanism of activity also evaluated in a diet-induced mouse model and adipocytes in vitro. The pilot clinical study showed a reduction in body weight with a significant decrease in waist circumference and BMI.

Strength of evidence: One small pilot RCT (n=30) provides preliminary positive evidence. The small sample size and single-study nature mean results must be interpreted cautiously and require replication in larger trials.

5.5 Gastrointestinal Conditions

Since centuries, Cyperus rotundus L. has been used against gastric ailments in traditional Indian medicine, especially in Ayurveda and Siddha.

Preclinical evidence: Modern research has demonstrated gastroprotective effects of C. rotundus extracts against ethanol-induced and aspirin-induced gastric ulceration in animal models. Studies have indicated that the rhizomes of C. rotundus are used as traditional folk medicine for the treatment of stomach and bowel disorders and inflammatory diseases in Asian countries.

The collected information suggest that C. rotundus has limited activity against different forms of infectious diarrhea due to its selective activity against diarrheal pathogens.

Strength of evidence: Antidiarrheal and gastroprotective evidence is primarily from animal studies and in vitro models. No large-scale clinical trials for gastrointestinal indications are reported in the reviewed sources.

5.6 Neuroprotection and Central Nervous System

Modern pharmacological studies have shown that C. rotundus possesses neuroprotective and antidepressant effects, among other biological activities.

Preclinical evidence: Cyprotuoside A and cyprotuoside B showed remarkable antidepressant activity in despair mice models. A study evaluated the effects of C. rotundus extract and its active metabolite α-cyperone on paclitaxel-induced neuropathic pain; oral administration of C. rotundus extract at doses of 500 mg/kg and intraperitoneal administration of α-cyperone at doses of 480 and 800 μg/kg prevented both the development of cold and mechanical pain. The results indicated that C. rotundus at doses of 300 and 500 mg/kg significantly alleviated paclitaxel-induced cold allodynia, while mechanical allodynia was significantly reduced only at 500 mg/kg, with the most potent analgesic effect observed at the highest dose.

Strength of evidence: All neuroprotective evidence is preclinical (animal or cell-based). No human clinical trials have been identified in the reviewed sources.

5.7 Antimicrobial and Antiparasitic Activity

Studies have confirmed anti-candida, anti-helminthic, anti-malarial, and anti-viral activities of C. rotundus and its chemical constituents.

Anthelmintic clinical/animal evidence: In vivo therapeutic effects of C. rotundus fractions were evaluated using the fraction that showed the most promising in vitro anti-Trichinella spiralis potential. Histopathologically, treated groups showed a remarkable improvement in the small intestine and muscle changes. Maximal therapeutic effects were detected in the combination therapy. C. rotundus extracts may have anti-T. spiralis potential, particularly when combined with albendazole.

Strength of evidence: Predominantly animal and in vitro preclinical data. The combination anthelmintic study used an animal model; no human clinical evidence is available from the reviewed sources.

5.8 Anticancer Activity

Cell-based evidence: Treatment of ethanol crude extraction of C. rotundus (CRE) on HeLa cells caused morphological changes and induced chromatin condensation; DNA microarray analysis showed that CRE led to up-regulation of 449 genes and down-regulation of 484 genes, classified in several interaction pathways.

The compound 11,12-dihydroxyeudesm-4-en-3-one showed a potent proliferation inhibitory effect against ovarian cancer A2780 cells (EC50: 11.06 ± 0.25 μM) compared to another compound from the same plant. The same compound also exhibited detectable cytotoxicity against endometrial adenocarcinoma Ishikawa cells (EC50: 6.46 ± 0.12 μM).

Strength of evidence: All anticancer evidence is from in vitro cell-line experiments. No animal tumor studies or human clinical trials are cited in the reviewed sources for C. rotundus alone as an anticancer agent.

5.9 Skin and Cosmetic Applications

The anti-inflammatory function of C. rotundus in experimental studies has implied that it has the potential to cure inflammatory skin disorders. Extrapone, a formulation found in many skin whitening creams, is made from the powdered extracts of nutgrass galingale rhizome (C. rotundus). Tyrosinase inhibition, which relates to melanin synthesis reduction, has been identified as one mechanism underlying its skin-lightening reputation, though clinical human evidence for this specific application in the reviewed sources is limited.

5.10 Cardiovascular Effects

Modern pharmacological studies have shown that C. rotundus is commonly used in the treatment of nervous system, cardiovascular system, digestive system, uterus, and other diseases in clinical contexts. Preclinical evidence includes vasodilatory effects (via calcium channel blockade) and documented antiplatelet activity. Human cardiovascular clinical data are not well-represented in the reviewed sources.

6. Body Systems and Health Areas Associated with Nut Grass

Modern pharmacological studies have shown that C. rotundus has wide-ranging pharmacological activities, including antidepressant, hypoglycemic, antioxidant, anti-inflammatory, antipyretic, and analgesic effects. The following body systems are associated with its use across traditional systems and preclinical research:

• Digestive system: Gastritis, peptic ulcers, diarrhea, dysentery, IBS (traditional and preclinical)
• Reproductive / gynecological system: Dysmenorrhea, irregular menstruation, endometriosis, amenorrhea
• Musculoskeletal system: Arthritis, joint inflammation, pain management
• Metabolic system: Blood glucose regulation, anti-obesity
• Nervous system: Neuroprotection, pain (neurogenic and inflammatory), antidepressant, anticonvulsant, sedative
• Immune system: Anti-inflammatory, immunomodulatory, antiallergic
• Cardiovascular system: Antihypertensive, antiplatelet, cardioprotective
• Hepatic system: Hepatoprotective
• Integumentary (skin): Anti-inflammatory, tyrosinase inhibition (cosmetic)
• Infectious disease: Antimicrobial (antibacterial, antifungal/anticandidal), antimalarial, anthelmintic, antiviral

7. Dosage Forms and Dosages Reported in Studies

The following dosages are reported exactly as stated in source materials. They represent the forms used in research or traditional practice contexts and do not constitute recommendations.

Traditional Chinese Medicine (Decoction)

The recommended dosage of nutgrass galingale rhizome (Cyperus rotundus) in TCM practice is 6–9 g when used in a decoction.

Animal Study Dosages (Preclinical — Not Directly Translatable to Humans)

• Three different doses of C. rotundus extracts — 100, 300, and 500 mg/kg — were administered orally to evaluate preventive effects on paclitaxel-induced neuropathic pain. The results indicated that C. rotundus at 300 and 500 mg/kg significantly alleviated cold allodynia, while a significant analgesic effect on mechanical allodynia was observed only in the 500 mg/kg group.
• Intraperitoneal administration of α-cyperone at doses of 480 and 800 μg/kg prevented the development of both cold and mechanical pain.
• In anti-inflammatory models, doses of 300 mg/kg of crude extract have been used in rats.

Human Pilot Study

A standardized rhizome extract (CRE) containing 5% total stilbenoids (piceatannol, scirpusin A, scirpusin B) was evaluated over 90 days in a randomized, double-blind, placebo-controlled study of 30 obese individuals with BMI of 30–40 kg/m². The specific daily dose of CRE used in the human pilot study is not explicitly stated in the reviewed abstract.

Toxicity Thresholds

Acute oral toxicity studies following OECD guidelines reported that aqueous-ethanolic extracts at doses up to 2000 mg/kg caused no mortality or observable toxic symptoms in Wistar rats, indicating an LD50 greater than 2000 mg/kg. The LD50 of the essential oils was 5000 mg/kg in rats. A single oral administration of the ethanol extract at a dose of 5000 mg/kg did not produce signs of toxicity, behavioral changes, mortality, or differences in gross appearance of internal organs in rats.

8. Safety Considerations and Interactions

General Toxicological Profile

Toxicological assessments of C. rotundus extracts have demonstrated a favorable safety profile across various experimental models. Acute oral toxicity studies following OECD guidelines reported no mortality or observable toxic symptoms at doses up to 2000 mg/kg in Wistar rats (LD50 >2000 mg/kg). Thirty-day subacute toxicity studies revealed no significant alterations in behavioral parameters, body weight, hematological indices, or liver and kidney function biomarkers.

In vitro cytotoxicity evaluations using both malignant (MCF-7) and non-malignant (HEK-293) cell lines confirmed the low cytotoxic potential of the extracts, with IC50 values far exceeding the tested concentrations and minimal impact observed even at 1000 μg/mL in HEK-293 cells.

Toxicological assessments indicate that aqueous and ethanolic extracts possess a favorable safety profile with high LD50 values, although systematic clinical safety data remain limited.

CYP450 Enzyme Interactions

Safety assessments are frequently restricted to acute toxicity screenings in healthy models and fail to evaluate complex herb-drug interactions, despite evidence that C. rotundus modulates hepatic CYP3A4 enzymes. This modulation of CYP3A4 is pharmacokinetically significant because CYP3A4 is responsible for metabolizing a large proportion of commonly prescribed pharmaceutical drugs. The clinical relevance of this interaction in humans at typical use doses has not been formally quantified in RCTs reviewed here.

Limitations of Safety Data

Unoptimized clinical dosing regimens persist due to the absence of reliable Human Equivalent Dose (HED) modeling, as efficacy data derived from high-dose rodent studies cannot be linearly extrapolated to human physiology.

Genotoxicity

Genotoxicity was evaluated in one murine study by measuring structural chromosome aberrations in mice treated with 300 mg/kg of extract; the reviewed sources do not report genotoxic signals at this dose in standard assays, consistent with the overall low-toxicity profile observed.

Special Populations

Information regarding use in pregnancy, lactation, pediatric populations, or individuals with specific organ impairments is not systematically documented in the peer-reviewed clinical literature reviewed for this article. Traditional TCM sources caution against use during pregnancy.

Evidence Gaps and Research Translation Challenges

Current preclinical investigations predominantly utilize crude aqueous or ethanolic extracts with chemical heterogeneity and a lack of standardized quality markers, severely hampering reproducibility of therapeutic outcomes. Rigorous RCTs remain scarce, limiting clinical generalizability. The exact mechanisms of action are not very clear and require further evaluation, though the existing properties strongly suggest an extensive potential use of C. rotundus for clinical applications.

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