IngredientsScientific name: Begonia fimbristipula Hance. The species epithet fimbristipula refers to the fringed stipules characteristic of this taxon. It belongs to the family Begoniaceae, order Cucurbitales, and is placed within section Diploclinium. The native range of this species is southeastern China to Hainan and Thailand. It is a tuberous geophyte and grows primarily in the subtropical biome. Two subspecies are currently recognized: B. fimbristipula subsp. fimbristipula (the type, confined to southern China) and the recently described B. fimbristipula subsp. siamensis Phutthai & S.Radbouchoom (found in northern Thailand). Morphological differences between the two subspecies include tuber shape, petiole and peduncle trichomes, and number of female tepals; subsp. fimbristipula occurs in southern China (Fujian, Guangdong, Guangxi, Hainan, Hunan, Jiangxi, Zhejiang), while subsp. siamensis is found in northern and northeastern Thailand.
Common names include mountain begonia (English); Zibei Tiankui (紫背天葵, meaning "purple-backed heavenly mallow") and Hong Tong Cao (红铜草) in Chinese. A drink made with mountain begonia (Begonia fimbristipula Hance) is native to southeastern China. Flowering in May and fruiting in June, the tiny but resilient perennial plant can be found growing in cliff crevices and on damp rocks in mountain forests.
B. fimbristipula is a tuberous type, deciduous with a single ball-shaped tuber. The habit of Chinese begonias is rich in diversity, containing nearly all growth forms of the genus. Begonia fimbristipula requires typical shade-plant and acidophilic (pH 3.1–4.21) growing conditions, and its ideal temperature and humidity range is narrow. The complete chloroplast genome of Begonia fimbristipula has been characterized, and in 2025, a chromosome-level genome assembly of B. fimbristipula was published. The genome was assembled using a combination of Oxford Nanopore long-read data and Illumina short-read data, with an assembled genome size of 462.11 Mb.
Begonia fimbristipula is a medicinal herb distributed in the Chinese provinces of Fujian, Guangdong, Guangxi, Hainan, Hunan, Jiangxi, and Zhejiang, and it is on the verge of extinction due to habitat destruction and deterioration of its ecosystem. Begonia fimbristipula requires typical shade-plant and acidophilic growing conditions, and its ideal temperature and humidity range is narrow. Because of its high economic value, it has been excessively exploited to a degree that the wild populations have been greatly reduced. This species faces threats from climate change and human activities, particularly the local demand for its use in herbal tea. It was designated as a protected wild species by Guangdong Province, China, in 2023.
The plant is used primarily in the following forms:
Begonia fimbristipula has a history of use in traditional Chinese medicine (TCM), where it is known as "Hong Tong Cao" and is often included in herbal formulas intended to support liver health and address conditions such as hepatitis or liver stagnation. The traditional rationale for its use stems from its classification as a "cooling" herb that is thought to clear heat, detoxify, and support the flow of qi (energy) in the liver meridian. Historical texts and pharmacopeias from China mention its use for symptoms such as jaundice, fatigue, and digestive issues linked to liver imbalance.
Its leaves, dried stems, and flowers are used in Chinese herbal medicine to reduce inflammation, eliminate phlegm, and relieve cough and asthma. For centuries, its leaves and stems have been valued for their cooling and detoxifying properties. Healers traditionally used Begonia fimbristipula as a remedy for ailments such as sore throats, coughs, and fevers. Its tangy, tart flavor also made it a popular addition to teas and decoctions aimed at supporting respiratory health and alleviating mild digestive discomfort.
In traditional Chinese medicine (TCM), the mountain begonia is a valuable medicinal herb most commonly consumed as a herbal tea, with reputed health benefits ranging from reducing inflammation to eliminating phlegm. Its use as a cooling tea is particularly associated with Guangdong Province and the Hong Kong region, where it is served as a reddish-brown drink with a subtle floral, bittersweet flavor, considered the perfect tonic on hot days.
Historically, it has been incorporated into herbal formulations and traditional teas such as "Guangxi herbal tea," prized for its perceived cooling and detoxifying properties. Folk uses include alleviation of sore throat, cough, and inflammation, as well as support for digestive health. In TCM formulation practice, Begonia fimbristipula has often been combined with other botanicals to enhance synergistic effects and is frequently paired with honeysuckle, chrysanthemum, or licorice root in herbal infusions intended to clear heat and toxins from the body.
The genus Begonia L. (Begoniaceae), comprising about 2,151 species, is widely used in traditional medicine across various regions. Numerous Begonia species have been employed to treat a broad range of ailments, underscoring their ethnomedicinal significance. Despite their extensive traditional use, comprehensive scientific documentation on the ethnomedicinal applications, phytochemical profiles, and pharmacological properties of Begonia species remains limited. Across the genus, 41 Begonia species are used to treat ailments related to the respiratory system, skin, digestive system, and others.
The most thoroughly characterized phytochemicals specific to B. fimbristipula are anthocyanins. Its main components include cyanidin chloride, cyanidin-3-O-glucoside, and cyanidin-3-O-rutinoside (Tan et al., 2012). These were identified by Tan et al. through polyamide thin-layer chromatography (TLC) and HPLC. The characteristic purple-red coloration of the plant's leaves and stems, and of the tea produced from it, is attributable to these anthocyanin pigments. The antioxidant ability of the methanol extract may be mainly attributed to total phenols, especially cyanidin-3-O-glucoside.
The total phenolic content of the methanol extract of B. fimbristipula Hance (EBFH) was estimated using the Folin-Ciocalteu method and found to be 133.25 ± 2.88 pyrogallol/g. The antioxidant property was attributed to the total phenolic content of this Chinese drug.
Chemical profiling of various extracts of Begonia has revealed the presence of a number of bioactive compounds belonging to terpenoids, flavonoids, steroids, phenols, alkaloids, carbohydrates, anthocyanins, and many others. While these broad compound classes have been documented across multiple Begonia species, not all have been individually confirmed in B. fimbristipula specifically at the time of writing. Preliminary phytochemical analyses of B. fimbristipula have revealed the presence of bioactive compounds including flavonoids, polyphenols, and organic acids, which are associated with antioxidant and anti-inflammatory activities.
B. fimbristipula holds considerable economic significance as both a medicinal and food source; for example, the essential oil derived from B. fimbristipula has shown inhibitory effects against Streptococcus iniae Pier in tilapia. The specific constituent composition of the essential oil from this species has not been comprehensively detailed in publicly accessible peer-reviewed literature at the time of writing.
Like all members of the genus Begonia, B. fimbristipula contains calcium oxalate. Begonia leaves and stems contain oxalic acid, which the plant evolved as a defense against insects and herbivores, but which is also toxic to humans. The roots contain soluble calcium oxalates, which can lead to kidney stones and mineral deficiencies.
The most mechanistically characterized activity for B. fimbristipula is antioxidant action. The methanol extract (EBFH) was measured by various antioxidant methods, including a DNA damage assay, DPPH• assay, superoxide anion radical (O2•−) scavenging assay, ABTS•+ assay, Fe3+-reducing assay, and Cu2+-reducing assay. Results revealed that EBFH could effectively protect against hydroxyl-induced DNA damage. In addition, it could scavenge O2•−, DPPH•, and ABTS•+ radicals, and reduce Fe3+ and Cu2+. B. fimbristipula Hance can effectively protect against hydroxyl-induced DNA damage. One mechanism of this protective effect may be radical scavenging via donating a hydrogen atom (H•) or donating an electron (e−).
Several laboratory investigations have demonstrated that extracts of Begonia fimbristipula possess anti-inflammatory activity in vitro and in animal models. Research has shown that flavonoids and other phenolic compounds present in the plant can inhibit pro-inflammatory mediators such as nitric oxide (NO) and tumor necrosis factor-alpha (TNF-α). One study reported that aqueous extracts of the plant reduced ear edema in mice, indicating an anti-inflammatory effect. These mechanistic findings are, however, preclinical and have not been replicated in human clinical trials.
It has been demonstrated that compounds found in Begonia species, such as terpenoids, flavonoids, and alkaloids, hinder the growth of several bacteria and fungi, indicating the possibility of using them as natural substitutes for antibiotics in the treatment of infections and antibiotic resistance. For B. fimbristipula specifically, antimicrobial activity has been documented for the essential oil fraction against the fish pathogen Streptococcus iniae, though this has not been studied in the context of human infectious disease.
Evidence type: In vitro (laboratory). Evidence strength: Preliminary; no clinical data.
As a tea or functional vegetable in southeast China, Begonia fimbristipula Hance possesses various pharmacological effects including antioxidant ability; however, its antioxidant effect had not previously been reported. A study published in Oxidants and Antioxidants in Medical Science (Han, Liang, and Li, 2013) extracted the plant with methanol and tested the extract (EBFH) using multiple antioxidant assays. EBFH could effectively protect against hydroxyl-induced DNA damage, scavenge O2•−, DPPH•, and ABTS•+ radicals, and reduce Fe3+ and Cu2+. The total phenols content of EBFH was 133.25 ± 2.88 pyrogallol/g. This study was entirely in vitro; no human or animal subjects were involved, and no conclusions about clinical antioxidant effects in people can be drawn from it.
Evidence type: In vitro and animal (mouse) models. Evidence strength: Preliminary; no clinical data.
Some in vitro studies suggest that extracts from this plant may scavenge free radicals and inhibit inflammatory pathways, supporting its traditional use for managing minor ailments. One study reported that aqueous extracts of the plant reduced ear edema in mice, indicating an anti-inflammatory effect. However, while these preclinical results are promising, there is currently a lack of high-quality clinical trials in humans to confirm efficacy and safety for inflammatory conditions.
Evidence type: In vitro / applied aquaculture model. Evidence strength: Very preliminary; no human data.
The essential oil derived from B. fimbristipula has shown inhibitory effects against Streptococcus iniae Pier in tilapia. This finding is reported in the context of aquaculture disease management and has not been evaluated in human medicine. Across the broader Begonia genus, compounds such as terpenoids, flavonoids, and alkaloids hinder the growth of several bacteria and fungi, indicating the possibility of using them as natural substitutes for antibiotics in the treatment of infections and antibiotic resistance — though for B. fimbristipula specifically, this remains largely extrapolated from related species.
Evidence type: Traditional claim; no specific in vitro, animal, or clinical studies confirmed for this species. Evidence strength: Anecdotal / traditional only.
There is very limited scientific research directly validating the traditional hepatoprotective uses of B. fimbristipula. While some phytochemical studies have identified antioxidant and anti-inflammatory compounds in Begonia fimbristipula, there is a lack of robust in vitro, animal, or clinical studies specifically demonstrating hepatoprotective effects. Hepatoprotective activity has been described for other Begonia species within genus-level reviews but has not been specifically confirmed for B. fimbristipula.
Evidence type: Traditional use only; no clinical studies identified. Evidence strength: Anecdotal / traditional only.
Its leaves, dried stems, and flowers are used in Chinese herbal medicine to reduce inflammation, eliminate phlegm, and relieve cough and asthma (Han et al., 2013). No controlled clinical trials, randomized studies, or systematic reviews have been published evaluating the efficacy of B. fimbristipula specifically for respiratory outcomes in humans.
There is a notable lack of large-scale clinical trials or comprehensive human studies directly assessing the health benefits of Begonia fimbristipula as a nutritional ingredient. Most available evidence derives from laboratory or animal models, making it difficult to confirm efficacy and safety in human populations. Despite extensive traditional use, comprehensive scientific documentation on the ethnomedicinal applications, phytochemical profiles, and pharmacological properties of Begonia species remains limited. Existing studies are often fragmented, and the evidence supporting traditional claims is frequently inconsistent or preliminary.
There are currently no standardized clinical dosage recommendations for Begonia fimbristipula established by any major regulatory body (NIH, EMA, WHO, or equivalent). Published dosage information is limited to traditional practice and the extraction quantities used in preclinical laboratory studies. No human clinical trials specifying therapeutic doses have been published in the peer-reviewed literature identified in this review.
A primary, genus-wide safety concern for Begonia — including B. fimbristipula — is the presence of calcium oxalate. Begonia leaves and stems contain oxalic acid, which evolved as a defense against insects and herbivores but is also toxic to humans. Some begonia species have a history of culinary use in small, cooked amounts, yet raw parts still contain oxalic acid and crystals that can irritate the mouth and gut. People with kidney disease, a history of kidney stones, or mineral balance issues should avoid eating any part of common ornamental begonias.
The roots contain soluble calcium oxalates, which can lead to kidney stones and mineral deficiencies. Concentration of oxalates is highest in the underground parts: clinical signs of Begonia spp. ingestion include kidney failure (in grazing animals), vomiting, and salivation in dogs/cats, with the most toxic part being underground.
While the leaves, stems, and flowers all contain irritating calcium oxalate crystals, the concentration is not uniform throughout the plant. The most toxic parts of the begonia are the underground parts: roots, rhizomes, and tubers. Traditional Chinese herbal use of B. fimbristipula employs primarily leaves, dried stems, and flowers, which carry lower oxalate concentrations than the roots or tubers. Traditional preparation as a brewed tea (involving dilution and heating) may reduce the bioavailable oxalate load compared to raw consumption.
The toxicity of oxalic acid is due to kidney failure caused by precipitation of solid calcium oxalate. This concern is most acute for individuals with pre-existing kidney disease, a history of calcium oxalate kidney stones, or conditions affecting mineral homeostasis. While the herb is generally safe to consume in moderation, it is not recommended for kidney patients since begonias contain oxalic acid that may aggravate urine and kidney disorders.
Because of its high economic value, B. fimbristipula has been excessively exploited to a degree that the wild populations have been greatly reduced. Environmental vulnerability and human activities caused a sharp decrease of the wild populations. This species was designated as a protected wild species by Guangdong Province, China, in 2023. Consequently, this species faces threats from climate change and human activities, particularly the local demand for its use in herbal tea. This protected status raises questions about the sustainability and legality of supply chains for commercial herbal products based on wild-harvested material.
No formal toxicological studies, maximum tolerated dose evaluations, or long-term human safety data for Begonia fimbristipula as a dietary supplement ingredient appear in the peer-reviewed literature identified in this review. There is a notable lack of large-scale clinical trials or comprehensive human studies directly assessing the health benefits of Begonia fimbristipula as a nutritional ingredient. Most available evidence derives from laboratory or animal models, making it difficult to confirm efficacy and safety in human populations.
A 2025 Springer review aimed to consolidate and critically analyze the current knowledge on the ethnomedicinal uses, phytochemical constituents, and pharmacological activities of Begonia species, with information retrieved from databases such as Google Scholar, PubMed, ScienceDirect, and ResearchGate, resulting in the inclusion of 115 studies published up to April 2025. Despite this body of work, significant gaps remain for B. fimbristipula specifically:
Health conditions that Begonia fimbristipula may help support.
Body systems that Begonia fimbristipula may help support.
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