IngredientsMountain pepper (Tasmannia lanceolata (Poir.) A.C. Smith) is a species of flowering plant in the family Winteraceae, endemic to south-eastern Australia. It is commonly known by several names, including mountain pepper, pepper tree, and Tasmanian pepperberry, with the accepted synonym Drimys lanceolata. Other historical synonyms include Drimys aromatica, Tasmannia aromatica, and Wintera lanceolata.
The species was originally described by the French botanist Jean Louis Poiret. Until 1969 it was classified in the genus Drimys and was named Drimys lanceolata. Most authorities now follow A.C. Smith (1969) in recognizing the genus Tasmannia, which for others is a section within Drimys. Smith's interpretation was controversial and only became widely adopted following Doust and Drinnan's 2004 analysis based on molecular work.
The plant belongs to the Winteraceae family, which is part of the group known as palaeodicots, considered among the most primitive flowering plants because of their floral anatomy and wood structure.
Tasmannia lanceolata is a medium to large shrub (2–5 m in height) which is endemic to the woodlands and cool temperate rainforests of Tasmania and the south-eastern region of the Australian mainland. It is widespread in mountainous areas at altitudes of 300–1400 m (down to sea-level in Tasmania), where annual precipitation exceeds 1000 mm, in wet eucalyptus forest or dry sclerophyll woodland, temperate rainforest, often along watercourses, alpine shrublands, and granite outcrops in mountains.
It is a dioecious bushy shrub to small tree with lance-shaped or narrowly elliptic leaves, male and female flowers on separate plants, the flowers with 3 to 9 petals, and the fruit a deep maroon to glossy black berry. The stems, branches, and twigs are red in colour. The aromatic leaves are lanceolate to narrowly elliptical in shape (4–12 cm long, 0.7–2 cm wide) with a distinctly pale undersurface.
When the berry is air dried it forms a small, hard peppercorn suitable for milling or crushing. The berry has a pleasant spicy flavour and sharp aroma. The berries are sweet and fruity at first with a lingering peppery aftertaste.
Both the berries and the leaves are used in commercial and traditional contexts. Both leaves and berries may be used fresh or dried to add a spicy, peppery flavour to curries, cheese, salad dressings, and sauces. Flowers may be enjoyed fresh in salads or as a peppery garnish for a variety of sweet and savoury dishes. It can also be added to curries, cheeses, and alcoholic beverages, and is exported to Japan to flavour wasabi.
In Australia, the species has been brought into commercial cultivation for culinary use (berries), and for the extraction of the sesquiterpene polygodial, the source of the plant's characteristic peppery flavour, and an antifungal and antibacterial. Tasmannia lanceolata extract has been listed under the GRAS (generally regarded as safe) flavoring substances. It was evaluated and approved by the Expert Panel of the Flavor and Extract Manufacturers Association of the United States (FEMA). It is classified as FEMA No. 4755; its primary name is Tasmannia lanceolata extract, with the synonyms Drimys lanceolata extract and Drimys aromatica extract.
Low-safrole clonal selections are grown in plantations for commercial use, as safrole is considered a low-risk toxin. The extract is also formulated into topical cosmetic preparations for dermatological applications (discussed further below).
T. lanceolata was used as a flavouring agent by Australian Aborigines and, more recently, by European settlers. Historically, the leaves have been used as a herb and the berries have been used as a spice. Australian Aborigines also used T. lanceolata as a therapeutic agent to treat stomach disorders and as an emetic, as well as generally as a tonic.
In Aboriginal cuisine it was used both as a food flavouring and in traditional medicine as a treatment for skin disorders, venereal diseases, colic, and stomach ache. Traditionally, the plant was used for its antiseptic properties as well as its flavour. Both the leaves and fruit were used: Aboriginal people suffering from sore gums and toothaches would crush the berries with water to make a paste and applied it to treat the infection.
Tasmannia lanceolata has a long history of usage by Australian Aborigines and European settlers as a food flavouring agent. Aborigines also used it for the treatment and cure of skin disorders, venereal diseases, colic, stomach ache, and as a quinine substitute.
The 1889 book The Useful Native Plants of Australia records that the common name included "Pepper Tree" and that "the drupe is used as a condiment, being a fair substitute for pepper, or rather allspice [...] The leaves and bark also have a hot, biting, cinnamon-like taste." Used in colonial medicine as a substitute for Winter's bark, a stomachic, it was also used for treating scurvy. The tonic, made from ground berries, leaves, and bark, is also recorded as being used by early European settlers to treat scurvy.
In a lecture delivered to the Royal Horticultural Society in July 1931, Comber included Tasmannia lanceolata (as Drimys aromatica) in a group of prominent examples of 'showy shrubs' that colonial settlers had introduced to cultivation in England.
Multiple studies have reported that the drimane sesquiterpene polygodial is the major component responsible for the flavour and aroma characteristics of this species. A recent analysis of commercial essential oil components reported these to be predominantly sesquiterpenic, with polygodial (36.74%) being the major component. Some cultivated Tasmanian pepper leaf clones are found to contain polygodial as high as 64%.
A chemical profiling of the essential oil of Tasmanian pepper leaf identified the following sesquiterpene compounds: polygodial (36.74%), guaiol (4.46%), calamenene (3.42%), spathulenol (1.94%), drimenol (1.91%), cadina-1,4-diene (1.58%), 5-hydroxycalamenene (1.47%), bicyclogermacrene (1.15%), α-cubebene (0.88%), β-caryophyllene (0.87%), α-copaene (0.48%), cadalene (0.44%), d-cadinol (0.40%), elemol (0.39%), T-muurolol (0.39%), and germacrene-D (0.33%).
Polygodial is a drimane-type sesquiterpene dialdehyde and has been reported to have antimicrobial, antifungal, and antiparasitic potential.
The fruits contain benzoic acids, flavanols, and flavanones, as well as eugenol, methyl eugenol, and gallic acid, and also the glycosides quercetin, rutin, and possibly vitamin D. A 2023 study using LC-ESI-QTOF-MS/MS analysis of mountain-pepper berries identified an extensive polyphenol profile: the study identified 143 phenolic compounds, including 31 phenolic acids, 70 flavonoids, 10 isoflavonoids, 7 tannins, 3 stilbenes, 7 lignans, 10 other compounds, and 5 limonoids.
A 2023 PMC study also characterised the leaf profile: This study characterised the non-anthocyanin phenolic and organic acid profiles of aqueous extracts obtained from the leaves of T. lanceolata by UHPLC-Q-Orbitrap-MS/MS and UHPLC-TQ-MS/MS. A total of 39 non-anthocyanin polyphenols were tentatively identified in T. lanceolata extracts.
Both the leaves and the fruit contain polygodial, a peppery and hot compound which has been examined extensively in scientific journals. The pepperberry can also be used as a fish poison, reflecting high biological activity of its chemical constituents at sufficient concentrations. The dried leaves of Tasmannia lanceolata contain 0.67% w/w vitamin D₂.
The primary antifungal action of polygodial comes in part from its ability to function as a nonionic surfactant, disrupting the lipid-protein interface of integral proteins and denaturing their conformation. As a result, the antifungal mechanism of this sesquiterpene dialdehyde is associated with membrane functions or derangement of the membrane. For example, the glucose-induced medium acidification process of Saccharomyces cerevisiae was inhibited by polygodial, presumably caused by inhibition of the plasma membrane H⁺-ATPase. The potent antifungal activity of polygodial results from its multiple functions.
Polygodial can enter the cell membrane of microbes via passive diffusion, and once inside, it may react with various intercellular structures causing cell dysfunction. A 2021 genome-wide mutant screen study using the haploid deletion mutant library of S. cerevisiae provided additional mechanistic detail: polygodial triggers a dose-dependent vacuolar alkalinization and increases Ca²⁺ influx and inhibits glucose-induced Ca²⁺ signaling. Using the haploid deletion mutant library of S. cerevisiae, a genome-wide mutant screen was performed; 66 deletion strains were identified as hypersensitive and 47 as highly resistant to polygodial treatment.
Research published in the Journal of Agricultural and Food Chemistry (2017) elucidated the mechanism by which drimane sesquiterpenes from Tasmanian pepper produce pungency. Sensory-guided fractionation of extracts of Tasmanian pepper berries revealed 20 drimane sesquiterpenes, amongst which polygodial, warburganal, and 1β-acetoxy-9-deoxy-isomuzigadial exhibited the lowest pungency threshold concentrations on the tongue surface (0.6–2.8 nmol/cm²) and elicited a dose-dependent calcium influx into mTRPA1-expressing CHO cells with the lowest EC₅₀ values (4.5 ± 1.0 – 16.7 ± 7.5 µmol/L) and a good correlation to oral pungency thresholds (R² = 0.986).
Calcium imaging assays demonstrated these chemosensates to induce a calcium influx into cultured trigeminal neurons prepared from wildtype (TRPA1⁺/⁺) mice, whereas no calcium influx was observed in neurons from TRPA1 knockout mice (TRPA1⁻/⁻), confirming the α,β-unsaturated 1,4-dialdehyde structure to be the required structural motif for low oral pungency thresholds and activation of Transient Receptor Potential Channel A1 (TRPA1). Time-resolved NMR experiments confirmed the pungency-mediating mechanism for electrophilic drimane sesquiterpene dialdehydes to be different from that found for other electrophilic pungent agents like isothiocyanates, which undergo a covalent binding with cysteine residues in TRPA1. Instead, polygodial and related compounds showed immediate reactivity with the ε-amino group of lysine side chains to give pyrrole-type conjugates.
Beyond TRPA1, polygodial from Tasmannia lanceolata has also been identified as an activator of TRPV1 in published reviews on transient receptor potential channels as targets for phytochemicals. Polygodial, a lipophilic drimane-type sesquiterpene dialdehyde, has known activity at transient receptor potential channel family members including TRPA1 and TRPV1. Research further assessed polygodial's activity at NaV1.7 and NaV1.8, two key isoforms of the voltage-gated sodium channel family involved in nociception, using automated whole-cell patch-clamp electrophysiology. The compound inhibits members of the voltage-gated sodium channel family, specifically NaV1.7 and NaV1.8, without changing the voltage-dependence of activation or inactivation.
Cell-based in vitro research has examined the anti-inflammatory properties of Tasmanian pepper leaf extract. A PMC study found that suppression of LPS-induced expression of COX-2 and iNOS and decrease of NO and PGE₂ levels suggests potential anti-inflammatory properties of the extracts. Anise myrtle, lemon myrtle, and bay leaf selectively inhibited COX-2 and iNOS enzymes, while Tasmannia pepper leaf extract exhibited a pronounced inhibitory activity toward COX-1 and was the least effective inhibitor of COX-2 in that comparison. These results are from in vitro cell-based experiments and do not constitute clinical evidence of anti-inflammatory effects in humans.
The antimicrobial activity of T. lanceolata extracts is among the most extensively documented areas in published laboratory literature. Dried T. lanceolata berries and leaves have strong antimicrobial activity against food spoilage organisms. The Tasmanian pepper leaf extract has broad-spectrum antimicrobial activity and is very effective against fungi, especially yeasts, demonstrating its potential to be used in the food industry as a natural preservative.
In a published PMC study examining solvent extracts of T. lanceolata against food spoilage yeasts (including Candida albicans, Candida krusei, Dekkera anomala, Rhodotorula mucilaginosa, Saccharomyces cerevisiae, and Schizosaccharomyces pombe), as well as against Escherichia coli and Staphylococcus aureus via the agar disc diffusion method: extracts showed broad-spectrum antifungal activity against weak-acid resistant yeasts in comparison to the standard antifungal agents, fluconazole and amphotericin B. Dekkera anomala was the most sensitive and strongly inhibited by all extracts, while E. coli was the least sensitive. Polygodial, identified as the major bioactive compound in T. lanceolata, was the key active agent, and hexane extracts contained the highest amount of bioactive compounds and demonstrated the strongest antimicrobial activities.
A 2022 PMC study further confirmed antifungal efficacy for post-harvest food applications: in an in vivo storage study, dates were treated with three different concentrations of T. lanceolata leaf extract (12.5, 25, and 50 µg/mL) and stored at 30°C. Treatment exhibited potent antifungal activity against most tested fungi, where minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) were below 25 µg/mL for polygodial.
Evidence strength: The antimicrobial/antifungal evidence base is robust at the in vitro and food-application level. No controlled human clinical trials evaluating therapeutic antimicrobial use have been identified in the published literature. Evidence of anti-Proteus mirabilis activity exists in vitro: fruit extracts of the plant strongly inhibited growth of Proteus mirabilis, which is a bacterial trigger for rheumatoid arthritis, but this remains preliminary and laboratory-based.
Mountain pepper also has high antioxidant activity. A 2023 study published in PMC (Ali et al., University of Melbourne / University of Leeds) examined mountain-pepper berries alongside other Australian native foods using DPPH free radical scavenging and reducing power assays. Australian mountain-pepper berries represent a rich reservoir of bioactive phenolic metabolites (phenolic acids, flavonoids, isoflavonoids, tannins, stilbenes, lignans, and limonoids). The analysis provided evidence that T. lanceolata possesses high antioxidant potential, a property that could be exploited in the development of specific biopharmaceuticals. Methanol and ethanol extracts reveal the highest phenolic content and antioxidant properties.
Evidence strength: Antioxidant effects are well established via multiple in vitro analytical methods. There are no published human clinical trials specifically designed to test the antioxidant efficacy of mountain pepper as a supplement in human subjects.
The 2023 study by Ali et al. analyzed mountain-pepper berries for phenolic and non-phenolic metabolites and their antioxidant and alpha-glucosidase inhibition activities, using LC-ESI-QTOF-MS/MS. The analysis provided evidence that T. lanceolata possesses high antioxidant and antidiabetic potential, with alpha-glucosidase inhibition activity observed in vitro. Additionally, in silico molecular docking was employed in this study. Evidence strength: This work is entirely in vitro and in silico. No human clinical trials investigating mountain pepper's effect on blood sugar regulation have been identified.
The most advanced area of human clinical evidence for mountain pepper extract is in topical dermatology. A double-blind, randomised, placebo-controlled clinical trial was published in the Journal of Cosmetic Dermatology (2021): using Tasmannia lanceolata extract (TLE) significantly reduces the dermal roughness of stretch marks in women. The trial included 29 women (mean age 47.0 ± 10.2 years; range, 25 to 60 years) with a mean body mass index (BMI) of 26.9 ± 7.0 kg/m². The patients presented with noninflammatory and nonpigmented stretch marks of more than 6 months' duration, with hollow lesions less than 1 cm wide. The investigators applied TLE and placebo topically every day for 8 weeks; 15 participants received TLE and 14 received placebo. Dermal density and thickness were evaluated using ultrasound, while stretch mark conditions (length, colour, and depth) were determined by clinical scoring. Matricial proteins (pro-collagen I and elastin) and pro-matricial factors, like TGF-β concentrations, were quantified from cultures of human skin explants.
The tested composition induced a significant increase in the thickness of the dermis of stretch marks after 8 weeks of treatment (p<0.01) measured by ultrasound. An increase in the thickness of the dermis at the level of stretch marks was observed in 87% of subjects with the tested composition. After 8 weeks of daily application, subjects noted a strong improvement in the appearance of stretch marks: stretch marks were less visible for 80% of subjects; less deep for 80% of subjects; skin was softer for 93% of subjects; skin was smoother for 80% of subjects.
Future studies may target the anti-inflammatory and skin-restructuring properties of TLE, as well as the extract's potential to treat other skin conditions, such as acne or surgical scars. Several study authors declared affiliations with the pharmaceutical industry.
Evidence strength: The single randomised controlled trial (n=29) is the only published controlled human trial for mountain pepper extract in any health indication. The small sample size, industry affiliations among authors, and the restriction to a single cosmetic indication mean this evidence should be considered preliminary. The ex vivo skin explant data provide mechanistic support but are not clinical outcomes.
The biological activity of polygodial has been reported in the scientific literature to include antifungal and antimicrobial activities and antihyperalgesia, which helps reduce pain. Animal and cell studies have documented the anti-inflammatory properties of polygodial more broadly; a published paper referenced in PMC is titled "Additional evidence for the anti-inflammatory and anti-allergic properties of the sesquiterpene polygodial" (Da Cunha et al., Life Sciences, 2001). However, these findings are preclinical and have not been confirmed in human clinical trials. Evidence strength: Preclinical only (animal models and in vitro). No human trials found.
A study cited in academic literature investigated the ability of Tasmanian pepper extracts to inhibit Proteus mirabilis, proposed as a microbial trigger of rheumatoid arthritis (RA). The study was undertaken to test the ability of Tasmanian pepper extracts to block the microbial trigger of RA and to use metabolomics fingerprint analysis to detect anti-inflammatory compounds. Tasmanian pepper berry and leaf were extracted with solvents of varying polarity and investigated for their ability to inhibit the growth of the bacterial trigger of RA (P. mirabilis). Evidence strength: In vitro only. No human data.
No standardised therapeutic dosage for mountain pepper has been established by any regulatory or pharmacopeial body. The following dosages and forms appear in source-cited scientific studies:
The most significant documented safety concern with T. lanceolata is the presence of safrole, a phenylpropanoid compound. The presence of safrole in T. lanceolata is concerning as it has been reported to be mildly genotoxic and carcinogenic in rats. Furthermore, safrole is also a weak hepatotoxin and has been shown to induce oxidative damage to liver cells. The carcinogenicity and toxicity of safrole has been shown to be due to the conversion by rat cytochrome P450 enzymes to electrophilic esters which form covalent adducts with DNA. In the past, safrole was widely used as an additive to beverages such as root beer and sassafras tea, although its use is now banned by the US Food and Drug Administration (FDA) as a food additive, and monitoring of its levels is recommended in products in which it occurs naturally.
Importantly, however, those early carcinogenesis/toxicity studies were performed in rodent experimental systems. Parallel safrole metabolism studies in humans demonstrated that the carcinogenic metabolites present in rat urine were absent in humans. Safrole is prohibited from direct addition to food or use as human food in the United States. In practice, low-safrole clonal selections are grown in plantations for commercial use, as safrole is considered a low-risk toxin.
Tasmannia lanceolata extract has been approved as a generally regarded as safe (GRAS) flavoring ingredient by the Flavor and Extract Manufacturers Association (FEMA No. 4755). This designation applies specifically to its use as a flavouring agent at typical culinary concentrations, and does not extend to therapeutic supplemental dosing.
Polygodial activates TRPA1 and TRPV1 channels — the same ion channels targeted by capsaicin and other pungent compounds — which are expressed in sensory neurons throughout the gastrointestinal tract and oral mucosa. At concentrations producing significant pungency, mucosal irritation is an expected biological effect consistent with the mechanism of action. The pepperberry has also been documented to be usable as a fish poison, indicating that high-concentration exposure can be biologically toxic to certain species. No systematic human safety studies characterising adverse events at supplemental doses have been identified in the published literature.
Polygodial is also used as an insecticide for its antifeedant properties — it causes insects to starve. This ecological toxicity is relevant to understanding the compound's potency but has not been linked to known adverse effects in human consumers at culinary-level exposure.
Apart from the reported ethnopharmacological uses of Tasmanian pepper, surprisingly few studies have rigorously examined this species for its medical properties. No pharmacokinetic data in humans, no drug interaction studies, and no long-term human safety data are available in the published literature. The industrial GRAS status is based on its use as a food flavouring, not as a concentrated dietary supplement.
Health conditions that Mountain pepper may help support.
Body systems that Mountain pepper may help support.
Go back