Amomum

Amomum: A Comprehensive Reference

1. Identity, Taxonomy, and Botanical Classification

The tropical ginger genus Amomum (Zingiberaceae) has always posed challenges for classification based on morphological characters. Amomum Roxb. is the second-largest genus in the Zingiberaceae Martinov family after Alpinia and includes approximately 111 to 150 species distributed in tropical Asia and Australia, particularly in Southeast Asia, such as India, Malaysia, and Indonesia. It is distributed from the Himalayas throughout Southeast Asia to northern Australia and extends into the central Pacific, with the centre of endemism being the forests of Southeast Asia.

The tropical ginger genus Amomum has always posed challenges for classification based on morphological characters. Previous molecular phylogenetic studies showed Amomum to be paraphyletic, but limited sampling and absence of data of the type Amomum subulatum made it impossible to resolve the paraphyly and make nomenclatural changes. Three genera — Conamomum, Meistera, and Wurfbainia — have been resurrected, and three new genera — Epiamomum, Lanxangia, and Sundamomum — have been described, together with a key to the genera and a nomenclatural synopsis placing 384 specific names (including all synonyms) into the new generic framework. Studies indicate that Amomum exhibits significant differences in morphology, habit, inflorescence, and capsule structure, with previous studies indicating that Amomum belongs to a polyphyletic lineage.

In practical usage across medicine, pharmacopoeia, and dietary supplement contexts, the term "Amomum" most commonly refers to one of several economically and medicinally significant species. The three most prominent are:

• Amomum subulatum Roxb. — Commonly known as Black Cardamom, Large Cardamom, Greater Cardamom, Hill Cardamom, or Bengal Cardamom. This species is the type species of the genus, described by Roxburgh. It is a perennial herb primarily cultivated in moist, hilly regions near water sources across the Eastern Himalayan belt, including India, Nepal, and Bhutan.
• Amomum villosum Lour. — Known in Chinese as Sha Ren or "Villous Amomum," and in commerce as Fructus Amomi. Amomum villosum Lour. is a perennial herb of the Zingiberaceae family, cherished for its fruits, flowers, and rhizomes which hold significant value in traditional medicine. Its distribution primarily spans the tropical and subtropical regions of Asia, including China, India, Thailand, Vietnam, and other Southeast Asian areas.
• Amomum tsao-ko Crevost & Lemarié (syn. Lanxangia tsaoko) — Known as Tsaoko or Chinese Black Cardamom, called Caoguo (草果) in Chinese. It is a perennial Zingiberaceae herb, mainly growing in the warm and humid southwestern China and northern Vietnam.

In China, Amomum comprises 39 species (29 endemic and 1 introduced), mainly distributed across the Fujian, Guangdong, Guangxi, Guizhou, Yunnan, and Tibet provinces. Among these, six species are listed in the Chinese Pharmacopoeia.

Common Names and Synonyms

• Amomum subulatum: Black Cardamom, Large Cardamom, Greater Cardamom, Brown Cardamom, Bengal Cardamom, Nepal Cardamom, Badi Elaichi (Hindi), Alaichi (Nepali)
• Amomum villosum: Sha Ren (砂仁, Chinese), Villous Amomum, Fructus Amomi, Sharen, Amomi Fructus, Cardamome médicinale (French)
• Amomum tsao-ko: Tsaoko, Caoguo (草果, Chinese), Chinese Black Cardamom, Tsaoko Fructus

Common Preparations and Dosage Forms

The dried ripe fruits are used mainly in Chinese Traditional Medicine and are registered in the Pharmacopoeia of the People's Republic of China. They are used in the treatment of gastrointestinal bloating, spasms and pains, and to stabilize pregnancy. Preparations encountered in research and commerce include dried whole or powdered fruit, essential oil obtained by hydrodistillation of seeds or rind, aqueous decoctions (teas), alcoholic extracts, standardized water extracts, and fixed-oil preparations. Today 60% of cardamom is consumed in food preparation, and 40% is used in the pharmaceutical, cosmetic, and perfume industries.

2. Traditional and Historical Use

Ayurvedic and South Asian Traditions

Amomum subulatum Roxb., commonly called Badi Elaichi or Greater Cardamom, is an important medicinal and aromatic spice belonging to the Zingiberaceae family. Historical references indicate its medicinal application dates back to ancient Ayurvedic literature. It is a perennial herb primarily cultivated in moist, hilly regions near water sources across the Eastern Himalayan belt, including India, Nepal, and Bhutan. The spice is valued both for culinary flavouring and its long-standing use in traditional Ayurvedic and Unani medicine.

It is mentioned in Ayurveda for a variety of health benefits, including for dental, skincare, kidney, heart, nausea, circulation, detoxification, digestion, asthma, stimulants, astringents, and many others. Amomum subulatum Roxb. is a major cash crop in the Himalayan region of India and is valued for its historical and traditional importance. This plant is well-known in the treatment of snake and scorpion bite, teeth problems, throat ailments, lung congestion, eye-lid inflammation, pulmonary tuberculosis, and digestive disorders.

It is reported as an official drug in the Ayurvedic Pharmacopoeia due to its curative as well as preventive properties for various ailments.

Unani Medicine

Small cardamom known as 'Heel Khurd' (Elettaria cardamomum) and large cardamom 'Heel Kalan' (fruits of Amomum subulatum Roxb.) are used in the Unani System of Medicine to treat gastrointestinal disorders. These seeds are used as stomachic (Muqavvi-e-Meda), desiccant (Mujaffif), resolvent (Muhallil), digestive (Hazim), and carminative (Kasir-e-Riyah).

Traditional Chinese Medicine (TCM)

Amomi fructus has been in use medically for more than 1300 years to treat cold deficiency of the spleen and stomach, loss of appetite, vomiting, and diarrhea. Additionally, it is also used as herbal tea or spice in China and Southeast Asia.

The dried ripe fruit of Amomum tsao-ko, called Tsaoko Fructus (Caoguo in Chinese), smells aromatic and spicy and has been used as both folk medicine and food additive. The earliest record of the medicinal application of Tsaoko Fructus can be dated back to the Official Prescription of the Royal Medical Prescriptions (Taiping Huimin Heji Ju Fang) and Summary of Medicinal Herbs in Baoqing in the Song Dynasty. Since then, the actions, compatibility, and prescriptions of Tsaoko Fructus had been developed and recorded in successive ancient medical books such as Yanshi Ji Sheng Fang in the South Song dynasty, Wen Yi Lun in the Ming dynasty, and Wen Bing Tiao Bian.

The indications of classical prescriptions are primarily for treating spleen and stomach disorders and epidemic febrile diseases including malaria. In China, the dried A. tsao-ko, named "Cao Guo," is a Traditional Chinese Medicine (TCM) which has been used to treat inflammation, lower body weight, and freshen the breath, and also exhibits strong anti-tumor and hypoglycemic activities.

In clinical practice, A. tsaoko is often used in treatment of dampness/cold resistance, malaria, vomiting, fullness, and epigastric distension across additional disorders, such as SARS, COVID-19, and hepatitis.

Southeast Asian and Other Traditions

The use of Amomum as a cooking spice and medicine has long been carried out by local people of Sumatra. The main traditional medicinal uses of plants of Amomum genus include treatments of stomach diseases, cancer, inflammation, malaria, and dental infections. Previous studies have mainly investigated Amomum species in different countries of Asia, including southern China, India, and Thailand.

Edmund Roberts noted on his 1834 trip to China that amomum was used as a spice to "season sweet dishes" in culinary practice.

3. Key Phytoconstituents and Active Compounds

Volatile Oils and Terpenoids

In Amomum subulatum: The fruit of A. subulatum contains 2–3% essential oils. The main component of the oils is the oxygenated monoterpene 'eucalyptol' or 1,8-cineole (65–80%), the concentration of which varies across cultivars and geographical conditions of cultivation. The essential oils from the seed and rind of Amomum subulatum Roxb. collected from Nepal were obtained by hydrodistillation and analyzed by GC-MS. A total of 87 components were identified among the two essential oils. The two essential oils were dominated by the monoterpenoids 1,8-cineole (60.8% and 39.0%), alpha-pinene (6.4% and 4.8%), beta-pinene (8.3% and 17.7%), and alpha-terpineol (9.8% and 12.3%). The monoterpene hydrocarbon content is in the range of 5 to 17%, of which limonene, sabinene, and pinenes are significant components. 1,8-cineole (60–80% of total volatile oil), α-terpineol, limonene, and α-terpinyl acetate are among the notable phytochemicals reported from Amomum subulatum.

In Amomum villosum (Fructus Amomi / Sha Ren): More than 100 phytochemicals have been isolated and identified from A. fructus, which mainly include volatile oils, saponins, flavonoids, organic acids, inorganic ingredients, and polysaccharides. Volatile oils of A. fructus mostly consist of borneol acetate (5–47%), camphor (4–17%), borneol (1.5–6%), camphene (0.2–3%), α-pinene (0.2–3%), and β-pinene (0.2–5%). Fruits contain an essential oil (at least 3%), with bornyl acetate being the main molecular compound (about 50%). A comprehensive 2024 review noted that about 500 compounds have been isolated and identified from various organs of A. villosum, including monoterpenoids, sesquiterpenoids, diterpenoids, flavonoids, phenols, polysaccharides, and other components.

In Amomum tsao-ko: At least 209 compounds have been isolated and identified from Tsaoko Fructus, most of which belong to terpenoids, phenylpropanoids, and organic acids. Geraniol, a major A. tsaoko essential oil component, is an extensively applied fragrant component with antibiosis, anticancer, anti-inflammatory, and insect resistance effects, and can restore the antibiotic effect on multidrug-resistant isolates.

Non-Volatile Secondary Metabolites

A total of 27 bioactive compounds have been identified in the seeds, fruits, and other parts of A. subulatum, including flavonoids, chalconoids, phenolics, alkaloids, and fatty acid esters. Diarylheptanoids represent the characteristic components of Zingiberaceae plants and exhibit different biological effects. Tsaokoarylone, a representative component of diarylheptanoids, showed widespread pharmacological effects, including anti-inflammation, antitumor, and anti-complementary activity. The chemical components of A. fructus include volatile components represented by borneol acetate, camphor, and borneol, and nonvolatile components including polysaccharides, flavonoid glycosides, inorganic components, and organic acids.

Summary of Key Chemical Groups Across Principal Species

• Monoterpenes: 1,8-cineole (eucalyptol), α-pinene, β-pinene, α-terpineol, limonene, camphene
• Oxygenated monoterpenes: Bornyl acetate, borneol, camphor, α-terpinyl acetate
• Sesquiterpenes: Spathulenol, β-elemene, allo-aromadendrene, caryophyllene
• Acyclic monoterpene alcohols: Geraniol (particularly in A. tsao-ko)
• Diarylheptanoids: Tsaokoarylone, tsaokoarilon (neolignane)
• Flavonoids and phenolics: Various flavonoid glycosides and phenolic acids
• Polysaccharides
• Alkaloids and fatty acid esters (in A. subulatum)

4. Mechanisms of Action

Anti-Inflammatory Pathways

An ethanol extract of A. tsao-ko (designated NNMBS227) exhibited potent anti-inflammatory activities in RAW264.7 macrophages. The effect was investigated in the suppression of pro-inflammatory mediators, including pro-inflammatory enzymes (inducible nitric oxide synthase and cyclooxygenase-2) and cytokines (tumor necrosis factor-α and interleukin-1β) in LPS-stimulated macrophages. NNMBS227 also inhibited the phosphorylation and degradation of IκB-α, as well as the nuclear translocation of nuclear factor kappa B (NF-κB) p65 caused by stimulation with LPS. The compound (1R,4S,6S)-1,6-dihydroxy-2-menthene from A. tsao-ko exerted anti-inflammation through suppressing NO generation by decreasing iNOS expression within LPS-treated RAW264.7 cells, with an IC50 value of 82.5 µM.

A new compound isolated from A. villosum stems and leaves showed a significant antioxidant effect via activation of NRF2/HO-1 pathways.

Antioxidant Mechanisms

Amomum subulatum has strong antioxidant properties due to its phenolics, flavonoids, and volatile oils. The mechanisms include free radical scavenging (neutralizing reactive oxygen species such as superoxide and hydroxyl radicals) and inhibition of lipid peroxidation, which prevents oxidative damage to cell membranes.

Gastrointestinal Motility and Protection

The main pharmacological effects of Fructus Amomi involve gastrointestinal protection, reducing blood viscosity, improving hemorheological characteristics, accelerating fibrin degradation, antioxidant activity, anti-infection activity, improving glucose metabolism disorders, and analgesic activity.

Anticancer / Cytotoxic Mechanisms

The research demonstrated that tsaokoarylone dramatically suppressed LPS-mediated NO generation within BV2 microglial cells at 1–100 µM. Tsaokoarylone had significant antiproliferative activity within mouse neuroblastoma N2a cells (with IC50 values of 46 µM) and anticancer effect on human A549 lung cancer cells as well as human SKMel-2 melanoma cells. The ethanol extract of Amomum species was found to have significant cytotoxicities against some cancer cells, such as cervical cancer cell HeLa, hepatoma cells HepG-2 and SMMC-7721, lung cancer cell A549, and gastric cancer cell SNU638.

Antimicrobial Mechanisms

Research aimed to investigate the antibacterial mechanism of A. villosum essential oil in methicillin-resistant Staphylococcus aureus (MRSA). The metabolite profile of MRSA was acquired, and metabolic pathways were assessed for significant alterations caused upon treating bacterial cells with the essential oil. Metabolomics analysis revealed that 72 metabolites and 10 pathways were significantly affected. The essential oil specifically disrupted amino acid metabolism and the tricarboxylic acid (TCA) cycle, and also inhibited adenosine triphosphate (ATP) and reactive oxygen species (ROS) synthesis.

Hypoglycemic Mechanisms

Network pharmacology identified 11 core targets involved in oxidative stress and glucose metabolism, with functional enrichment pointing to the PPAR and steroid hormone signaling pathways. Molecular docking confirmed stable binding affinities of bornyl acetate, (−)-spathulenol, and (−)-pogostol to JAK2, NCOA2, and PPARA via hydrogen bonding and hydrophobic interactions. A. villosum extract demonstrated a concentration-dependent inhibitory effect against rat α-glucosidase. At concentrations of 1, 3, and 5 mg/mL, extract inhibited α-glucosidase activity by 31.99%, 48.85%, and 62.58%, respectively.

5. Scientific Evidence by Area of Use

5.1 Gastrointestinal Health

Strength of evidence: Mostly preclinical (in vitro and animal); limited human evidence.

The main traditional medicinal uses of plants of the Amomum genus include treatments of stomach diseases. Modern pharmacological studies have confirmed that A. villosum has the properties of gastrointestinal protection, anti-inflammatory activity, analgesic activity, antidiarrheal activity, antibacterial activity, and hypoglycemic activity.

Regarding antiulcer effects, the essential oils and petroleum ether soluble fractions of A. subulatum seeds were studied in rats for their ability to inhibit gastric lesions induced by aspirin and ethanol, and results were compared. Both fractions of the drug inhibited gastric lesions significantly, though fractions of small cardamom were found to be better than large cardamom. This represents preclinical animal data only; no controlled human trials on the antiulcer effects of Amomum specifically have been identified in the peer-reviewed literature.

A network pharmacology and in vivo investigation of Amomi fructus against gastric ulcers used multiple public databases to compile bioactive compounds and potential targets, with animal model validation, and found mechanisms relating to gastrointestinal mucosal protection, though the mechanism underlying this impact was still not fully known.

5.2 Cardiovascular Risk Factors and Lipid Metabolism

Strength of evidence: One small, unblinded human trial (n=30); preliminary.

Greater cardamom (Amomum subulatum Roxb.) fruit powder (seeds with pericarp) was evaluated for its effect on some cardiovascular risk factors in patients with ischemic heart disease. Thirty male individuals (50–70 years) with ischemic heart disease (old MI >6 months) were selected and divided into two groups of fifteen each. Group I (treated) received 3 g cardamom powder in two divided doses while Group II (placebo) received matched placebo capsules for 12 weeks. Blood samples were collected initially and at 6 and 12 weeks for analysis of lipid profile, fibrinolytic activity, and total antioxidant status. Administration of greater cardamom significantly (P<0.001) reduced atherogenic lipids without significant alteration in HDL-cholesterol. Plasma fibrinolytic activity and serum total antioxidant status were also enhanced significantly (P<0.05) at the end of the study.

An independent assessment of this trial noted that the subjects in Verma's study were hypertensive patients and it did not have any control group, which might be the reason for showing more benefits of cardamom. This is an important limitation. The evidence for cardiovascular effects of Amomum in humans therefore remains preliminary and is based on a single small study with methodological constraints.

5.3 Antiobesity / Weight Management

Strength of evidence: One randomized, double-blind, placebo-controlled trial; moderate for short-term weight outcomes.

One study aimed to assess how well Amomum villosum water extract (AVE) assisted overweight to moderately obese people in losing weight. Eighty participants were chosen at random for the AVE group or the placebo group. Subjects were given two tablets of the test substance after their two consistent meals daily for 12 weeks. Measurements of body mass index (BMI), body weight, percent body fat, body fat mass, visceral adipose tissue (VAT), lean body mass, subcutaneous adipose tissue (SAT), percent VAT, and percent SAT were taken at the start and completion of the experiment. After taking the products for 12 weeks, the AVE group lost considerably more weight than the placebo group (−2.04 ± 3.04 kg vs −0.30 ± 2.88 kg, respectively; P < 0.014). There were no negative effects associated with AVE consumption.

While this study represents a higher quality of evidence than the cardiovascular trial, replication in independent trials with larger populations is needed before firm conclusions can be drawn.

5.4 Anti-Inflammatory Activity

Strength of evidence: In vitro and animal studies only; no human clinical trials identified.

Research conducted through in-vitro studies, animal models, and compound analysis has revealed that both A. villosum and A. tsao-ko exhibit a diverse array of health-promoting properties. The anti-inflammatory activity is well-characterized in cell-based assays. As described above, NF-κB pathway suppression and iNOS inhibition have been documented in macrophage models. Essential oil, crude extract, and some compounds were observed to have pharmacological activities such as anti-biotics, anti-inflammation, and antioxidant, mostly via in vitro experiments. However, the mechanism of its medicinal uses remains unclear. No controlled human trials on the anti-inflammatory effects of Amomum species have been identified in the peer-reviewed literature.

5.5 Antimicrobial Activity

Strength of evidence: In vitro studies only; no human clinical trials identified.

Amomum essential oils have been studied for their chemical profiles, with limonene, allo-aromadendrene, 1,8-cineole, camphor, farnesyl acetate, α-pinene, β-pinene, caryophyllene, camphene, D-camphor, santolina triene, methyl chavicol, bornyl acetate, β-elemene, and δ-3-carene as major compounds. The oils extracted from Amomum plants have been reported to possess antimicrobial, antioxidant, insecticidal, larvicidal, cytotoxic, anti-scabies, and anti-inflammatory activities. All solvent and water extracts of Amomum species show significant antibacterial activities against both bacterial and fungal pathogens, due to the existence of various secondary metabolites in these extracts.

Studies on A. subulatum essential oils showed that seed and rind oils were only marginally cytotoxic (20% and 30% kill on MCF-7 cells at 100 µg/mL, respectively) and antibacterial (MIC ≥ 313 µg/mL), but A. subulatum rind oil was appreciably active against the fungus Aspergillus niger (MIC = 19.5 µg/mL).

5.6 Antioxidant Activity

Strength of evidence: In vitro studies only.

Recent studies have shown the antioxidant activity of the essential oils isolated from several Amomum species. The oils of A. subulatum fruits from India and Saudi Arabia were found effective against DPPH radical scavenging with IC50 values of 219.38 mg/mL and 203.79 mg/mL, respectively. The fruit oils of three cultivars of A. subulatum collected from India (seremna, varlangy, and sawney) were active on DPPH and ABTS radical cation. In the ABTS scavenging model, the IC50 values were found to be 27.96, 31.34, and 32.49 µg/mL, respectively, whereas these values in the DPPH scavenging model were 172.3, 216.9, and 274.3 µg/mL, respectively.

5.7 Anticancer / Antiproliferative Activity

Strength of evidence: In vitro and animal studies only; no human clinical evidence.

Several studies have been carried out on the fruits, seeds, roots, rhizomes, and leaves of Amomum species, with approximately 127 metabolites isolated as flavonoid, diterpenoid, diarylheptanoid, monoterpenoid, sesquiterpenoid, phenylpropanoid, phenolic, and steroid groups. Besides cytotoxicity, antioxidant, and anti-inflammatory potentials, isolated compounds were evaluated for cytotoxicity, antioxidant, anticancer, antiproliferative, anti-inflammatory, antifungal, antimicrobial, neuroprotective, platelet antiaggregation, and antidiabetic properties. Tsaokoarilon (neolignane) had antiproliferative and cytotoxic activity, with the highest reactions considered as lead compounds for further development.

5.8 Antidiabetic / Hypoglycemic Activity

Strength of evidence: In vitro and animal studies; one RCT on anti-obesity did not specifically assess glycemic outcomes in a diabetic population.

Research showed that A. tsao-ko extract maintained the structural integrity and functionality of the pancreas. The flavonoids present in A. tsao-ko exhibited remarkable antioxidant and antidiabetic properties, as demonstrated in both laboratory experiments and animal studies. This suggests that A. tsao-ko holds promise as a novel natural material and could be developed for use in functional foods and medicines related to the management of Type 2 Diabetes Mellitus. These findings are preliminary and limited to preclinical models.

5.9 Hepatoprotective / Liver-Related Effects

Strength of evidence: Animal model studies; no human clinical trials identified.

A study investigated whether the volatile oil of A. villosum could address nonalcoholic fatty liver disease via the gut-liver axis. The dried mature fruit of Amomum villosum has been historically used in China as food and in the auxiliary treatment of digestive system disorders. Numerous studies have shown that gastrointestinal function is closely related to the development of nonalcoholic fatty liver disease via the "gut-liver" axis. The experiment was conducted in male Sprague-Dawley rats on a high-fat diet and represents animal-model evidence only.

6. Body Systems and Health Areas Associated with Amomum

The ethnopharmacological use of Amomum subulatum has been described in various medicinal systems including Ayurveda, Unani, and Chinese for its therapeutic properties in mitigating gastrointestinal disorders, lung congestions, respiratory ailments, jaundice, tuberculosis, hyperlipidemia, inflammation, and ischemic heart diseases. Based on the totality of traditional records and research studies reviewed, the following body systems are associated with Amomum:

• Digestive / Gastrointestinal system: Most consistently associated area. Used traditionally for dyspepsia, bloating, vomiting, diarrhea, gastric ulcer, and abdominal pain. Supported by preclinical and some clinical data.
• Cardiovascular system: Associated with lipid-lowering, fibrinolytic, and antioxidant effects relevant to heart disease. Supported by one small human trial with limitations.
• Metabolic system (weight, glucose): Anti-obesity effects in one RCT; antidiabetic effects in preclinical studies only.
• Hepatic system: Hepatoprotective effects in animal models; traditional use for jaundice.
• Immune / Inflammatory system: Anti-inflammatory activity documented in vitro and in animal studies.
• Respiratory system: Traditional use for lung congestion, asthma, and tuberculosis; no modern clinical evidence identified.
• Antimicrobial: In vitro activity against bacteria and fungi including MRSA and Aspergillus niger.
• Oral health: Traditional use for dental infections and breath freshening; limited scientific study.

Isolated compounds and extracts exhibit a diverse range of biological activities, including anti-inflammatory, antioxidant, hepatoprotective, anti-tumor, hypoglycemic, antimicrobial, gastrointestinal regulation, immunomodulatory, bacterial regulation, anti-obesity, and estrogenic effects.

7. Dosage Forms and Reported Dosages

The following dosages reflect those reported specifically in identified research studies:

• Amomum subulatum fruit powder for ischemic heart disease: Thirty male patients (50–70 years) received 3 g cardamom powder in two divided doses for 12 weeks.
• Amomum villosum water extract (AVE) for obesity: Eighty female and male participants between the ages of 20 and 75 participated. Subjects were given two tablets of the test substance after their two consistent meals daily for 12 weeks.
• Amomum subulatum methanol extract (MEAS) in toxicity study: Administration of a 250 mg/kg body weight dose reported no acute and subacute toxicities in BALB/c mice according to OECD guidelines.
• The seeds of A. subulatum contain about 2–4% volatile oil.
• Amomum subulatum contains 1.95–3.32% of essential oil having characteristic aroma and medicinal properties.

There are noted imperfections in the current body of research, including that the action sites and mechanisms of pharmacological activities are not clearly established. No standard therapeutic dosage for Amomum species has been established by major international regulatory or pharmacopeial bodies such as the WHO, EMA, or NIH Office of Dietary Supplements as of the available published literature.

8. Safety Considerations

General Toxicological Profile

Toxicity research suggests that A. tsaoko actually belongs to the non-toxic substance, although citral and 1,8-cineole — two main components of A. tsaoko — are hepatotoxic (for citral) and display low acute toxicity and sub-chronic oral toxicity (for 1,8-cineole) respectively, but no obviously accumulative toxicity has so far been discovered for A. tsaoko.

A toxicity study on Swiss albino mice fasted overnight revealed that even at 5 and 10 times higher than the corresponding human dose, the total methanolic extract of the test drug showed no gross behavior modification or mortality up to 24 hours. Administration of a 250 mg/kg body weight dose of methanol extract of A. subulatum reported no acute and subacute toxicities in BALB/c mice according to OECD guidelines 423 and 407 (2008), respectively.

Identified Gaps and Limitations

The plants of the genus Amomum are used as dietary materials, but they still need to be studied in depth, taking into consideration their safety and mechanism of action. Many natural products from the genus Amomum present several interesting pharmacological properties. However, the therapeutic potential is hampered due to their hydrophobic nature, which leads to poor bioavailability. More conclusive studies on the safety, efficacy, and in vivo toxicity of extracts and pure compounds from the genus Amomum are needed to gain a better understanding of this genus.

Identification and Adulteration Concerns

The genus Amomum includes over 111 species, six of which are widely utilized as medicinal plants and have already undergone taxonomic revision. Due to their morphological similarities, the presence of counterfeit and substandard products remains a challenge. Accurate plant identification is therefore essential to address these issues.

Pregnancy

In traditional Chinese medicine, the dried ripe fruits of A. villosum have been used to stabilize pregnancy; however, no controlled human safety data for use in pregnancy are available from the peer-reviewed literature identified in this review. Given the presence of volatile oil components with known pharmacological activities, caution is warranted pending more data.

Evidence Quality and Limitations

Detailed insights into the molecular mechanistic pathways mediating the beneficial role of this traditional herb on cell/animal models and large-scale clinical trials are lacking. The research base for Amomum species is predominantly composed of in vitro assays, animal model studies, and a very limited number of human trials. The two human studies identified — one on cardiovascular risk factors and one on body weight — are small, conducted in specific populations, and have not been independently replicated at scale. Research conducted through in-vitro studies, animal models, and compound analysis has revealed diverse health-promoting properties, but translation of these findings to confirmed clinical benefits in humans requires substantially more rigorous investigation.

References

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• Amomum villosum Lour.: An insight into ethnopharmacological, phytochemical, and pharmacological overview — Journal of Ethnopharmacology (ScienceDirect)
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