Fact-checked by Grok 2 weeks ago

Tragacanth

Tragacanth gum, also known as gum tragacanth (E 413), is a natural, anionic polysaccharide exudate derived from the dried sap of stems and branches of various Astragalus species in the Fabaceae family, primarily Astragalus gummifer Labill. and Astragalus microcephalus Willd., which are native to arid regions of Iran and other parts of Western Asia.^[1]^[2] It appears as flattened, horny fragments or powder ranging from white to pale yellow, swelling in water to form a viscous, gel-like mucilage due to its high molecular weight components, including tragacanthin (water-soluble) and bassorin (water-swellable).^[1]^[2] Chemically, it is a complex mixture of acidic polysaccharides rich in galacturonic acid, arabinose, galactose, xylose, and fucose, with a molecular weight up to 850 kDa, exhibiting pseudoplastic flow and stability across a wide pH (3–10) and temperature range (up to 100°C).^[2] Production of tragacanth gum involves natural exudation or incision of the plant's aerial parts, primarily in Iran, which accounts for approximately 70% of global supply, followed by Turkey and Iraq; the gum is collected, dried, sorted by quality (e.g., ribbons, flakes, powder), and exported for industrial use.^[2]^[3] Historically documented since 300 B.C. in ancient texts for medicinal purposes, it has been a key natural hydrocolloid in traditional Persian and Ayurvedic medicine as a demulcent and emollient.^[4] Its biodegradability, non-toxicity, and biocompatibility have positioned it as a versatile material in modern applications beyond traditional uses.^[2] In the food industry, tragacanth gum functions as an emulsifier, stabilizer, and thickener in products such as dressings, sauces, confectionery, ice creams, and beverages, where it prevents separation, enhances texture, and improves mouthfeel at low concentrations (0.1–1%).^[1]^[5] In pharmaceuticals, it serves as a suspending agent, binder in tablets, and bulk-forming laxative, while in cosmetics, it acts as a viscosity enhancer in lotions and creams; emerging biomedical roles include drug delivery systems (e.g., hydrogels for controlled release) and tissue engineering scaffolds for wound healing and bone regeneration due to its film-forming and mucoadhesive properties.^[6]^[2] Its non-Newtonian rheology and high water-binding capacity (up to 50 times its weight) make it superior to some synthetic alternatives for these purposes.^[2] Regulatory bodies consider tragacanth gum safe for human consumption; the Joint FAO/WHO Expert Committee on Food Additives (JECFA) specifies no numerical acceptable daily intake (ADI), indicating low toxicity based on biochemical and metabolic studies, while the European Food Safety Authority (EFSA) concurs with no safety concerns for the general population at the refined estimated dietary exposure levels, despite potential allergenicity in sensitive individuals via inhalation or ingestion.^[1]^[7] In the United States, it is generally recognized as safe (GRAS) by the FDA for food use without quantitative limits, provided it meets purity standards such as loss on drying ≤16% and lead ≤2 mg/kg.^[1] No genotoxic or carcinogenic effects have been observed in long-term studies.^[7]

Etymology and History

Etymology

The term "tragacanth" originates from the Latin tragacantha, which itself derives from the Ancient Greek tragákanthe (τραγάκανθος), a compound of trágos (τράγος, meaning "goat") and ákantha (ἄκανθα, meaning "thorn"). This name alludes to the spiny, goat-thorn-like appearance of the shrubs in the genus Astragalus from which the gum is obtained.^[8]^[9] In Persian and Arabic traditions, the substance has been known historically as katirā (کتیرا), a term reflecting its regional significance as a natural gum exudate. This name, along with variants like katheera in Arabic, underscores its longstanding use in Middle Eastern pharmacopeias and trade.^[10]^[5]^[11] The word entered English in the mid-16th century through European trade routes connecting the Levant and Persia, with the earliest recorded use appearing in 1558 in a translation referencing the imported gum.^[12] Over time, this evolved into common English appellations such as "goat's thorn gum," mirroring the descriptive etymology across languages like French (tragacante) and retaining the thorny plant association in vernacular terms.^[9]

Historical Use

Tragacanth gum, derived from species of the Astragalus plant native to Persia, has roots in ancient medicinal practices dating back to at least the 3rd century BCE, when it was described by the Greek botanist Theophrastus as a valuable exudate used for its binding and soothing properties.^[13] In traditional Persian medicine, which influenced Unani systems, it served as an analgesic for treating coughs, lip fissures, and gastrointestinal issues, often prepared as a mucilage for internal and external applications.^[14] Its use extended to Ayurvedic traditions through cultural exchanges, where it functioned as an emulsifier in lotions and remedies for skin conditions and inflammation.^[15] By the medieval period, tragacanth's reputation spread through Islamic scholarship, with the polymath Avicenna documenting its application in the Canon of Medicine (c. 1025 CE) for formulations like hair dyes and demulcent pastes to soothe mucous membranes.^[16] Trade along the Silk Road facilitated its introduction to Europe around the 13th century, where it appeared in apothecary records and herbals as a prized import from Persian and Anatolian sources, valued for its stability in medicinal compounds. For instance, by 1305, it was recorded in the statutes of Pisa as a taxable import through Italian trading cities.^[17] This exchange integrated tragacanth into European pharmacology, building on its etymological ties to ancient Greek terms for "goat's thorn," reflecting the plant's thorny habitat. The 19th century marked a surge in tragacanth's industrial adoption in Europe amid textile and pharmaceutical advancements, where it was employed as a thickener in calico printing to fix dyes on cotton fabrics and as a suspending agent in early drug formulations.^[18] Iran, as the primary source, reached peak exports in the mid-20th century, particularly in the 1950s, supplying over 4,000 tonnes annually to meet demand from manufacturers worldwide before the rise of synthetic alternatives, geopolitical shifts, and overharvesting strained supplies.^[19] Following World War II, tragacanth's prominence waned post-1950s as synthetic alternatives like xanthan gum offered cheaper, more consistent alternatives for emulsification and stabilization in industry.^[20] However, renewed interest in natural biopolymers has spurred a revival in niche markets, particularly for sustainable pharmaceuticals and eco-friendly textiles, leveraging its biodegradable properties.^[15]

Botany

Plant Species

Tragacanth gum is primarily derived from Astragalus gummifer Labill., a perennial legume belonging to the family Fabaceae (Leguminosae), native to the Zagros Mountains region spanning Iran, Iraq, and Turkey.^[21]^[10] This species is classified under the order Fabales, clade Angiosperms, and kingdom Plantae, characterized by its role as a low-growing, spiny shrub that reaches heights of 30-60 cm at maturity.^[21]^[22] Several other Astragalus species contribute to tragacanth production, including A. microcephalus Willd., A. strobiliferus Boiss., A. gossypinus Fisch., A. parrowianus Mozaff., A. rahensis Bunge, and A. fluccosus Boiss., including several variants across Asiatic regions.^[10]^[23]^[24] These species share a similar morphology as thorny, evergreen shrubs, featuring compound pinnate leaves with numerous leaflets, pink to purple flowers arranged in axillary racemes, and extensive root systems that exude the gum upon injury.^[22]^[11]^[25] Genetic diversity among these Astragalus species and their subspecies significantly influences tragacanth gum quality, including variations in viscosity, sugar composition, and viscoelastic properties that affect its industrial applications.^[26]^[27] For instance, exudates from different variants exhibit distinct physicochemical profiles, with higher-quality gums often linked to specific genetic lines from A. gummifer and A. microcephalus that yield more translucent, ribbon-like structures.^[28]^[10]

Habitat and Cultivation

Tragacanth-producing plants, such as Astragalus gummifer, are native to arid and semi-desert regions across Western Asia, including Iran, Turkey, Iraq, Syria, Lebanon, and parts of Afghanistan, where they grow primarily at elevations ranging from 1,000 to 3,000 meters in drier mountainous areas.^[29]^[30] These environments feature low precipitation and harsh conditions, yet the plants require occasional water to support their growth on dry sub-alpine slopes and valleys below the tree line.^[29]^[31] The species prefer well-drained, rocky limestone or gravelly soils with minimal organic matter, which contribute to their exceptional drought resistance adapted to low-water availability.^[32] They perform best in sunny positions and tolerate poor, slightly alkaline conditions but are highly sensitive to overwatering, which can lead to root rot in less arid settings.^[32]^[33] Wild harvesting dominates tragacanth production, as the plants are collected from natural habitats rather than cultivated fields, with Iran and Turkey supplying the majority of global output.^[31] Limited cultivation efforts have been attempted in Iran since the early 2000s, focusing on propagation for gum production, but these face significant agronomic challenges including slow establishment rates and low economic yields compared to wild sources.^[31]^[34] Overharvesting from wild populations has raised concerns about sustainability, contributing to population declines and endangering some Astragalus species in key regions, while climate change exacerbates these pressures through increased aridity and habitat fragmentation in mountainous ecosystems.^[31]^[35]

Production

Harvesting

Tragacanth gum is traditionally harvested from mature shrubs of Astragalus species, such as A. gummifer and A. microcephalus, in arid and semi-arid regions. The process begins with the identification of plants typically 4-5 years old or older, as younger specimens yield insufficient exudate. Harvesters make shallow incisions, approximately 1-2 cm deep, on the roots or lower stems to stimulate sap flow, a method known as tapping. This is performed during dry seasons, often in late spring or summer (July through September in major producing areas), when low moisture and high temperatures promote optimal exudation without excessive plant stress.^[36]^[37]^[3] The sap that emerges from the incisions dries naturally in the arid air, forming brittle structures such as ribbons, flakes, or tear-shaped pieces over 2-4 weeks, depending on environmental conditions. Collectors return periodically to monitor the exudate and hand-pick the dried material once it has hardened sufficiently, ensuring minimal contamination from soil or debris. This manual collection is essential to preserve the gum's purity, as mechanical methods could introduce impurities. The process is inherently labor-intensive, requiring skilled workers to navigate rugged, remote terrains.^[38]^[5]^[3] Annual yields typically range from 0.5-2 g per healthy mature plant, with averages around 15 g depending on species and conditions, influenced by factors like plant age, overall health, and climatic conditions during the tapping period.^[31] Tapping occurs annually during the dry season, with sustainable practices limiting incisions to promote plant recovery and prevent overexploitation, which has led to population declines in some areas. Regional variations in technique reflect local traditions and plant morphology: in Iran, the primary producer supplying approximately 80% of global output and producing 1,500-2,000 metric tons annually as of recent estimates, root tapping predominates due to the deeper root systems of species like A. microcephalus, while in Turkey, stem incisions are more common on accessible branches. These operations often involve nomadic or semi-nomadic herders who traverse mountainous rangelands, combining gum collection with seasonal grazing.^[39]^[28]^[5]

Processing

Upon collection from incisions on the roots and stems of Astragalus species, raw tragacanth gum undergoes initial sorting to remove impurities such as dirt and plant debris, followed by grading into high-quality ribbons and lower-grade flakes based on color, form, and purity.^[5] In Iran, this sorting employs five distinct grades for ribbons and seven for flakes to ensure market standardization.^[39]^[2] The sorted gum is then cleaned through limited mechanical processes to eliminate remaining foreign matter, with natural drying occurring during the harvest season from August to November to preserve its structure without degradation.^[40] Further drying, if needed, is conducted at low temperatures to maintain integrity, avoiding high heat that could alter its properties.^[5] Subsequently, the cleaned and dried exudate is milled into a fine powder, typically achieving a particle size where 90% passes through a BSS 150 mesh sieve (approximately 106 microns) to enhance water solubility and uniformity for commercial use.^[40] In modern facilities, sterilization via gamma irradiation at doses around 10 kGy is applied to reduce microbial contamination while minimally affecting rheological properties.^[41] Quality control involves rigorous testing of each batch, including moisture content (limited to ≤16% loss on drying at 105°C for 5 hours, often achieving 8-13% in practice), viscosity of a 1% solution (typically 800 ± 150 cPs for standard grades or up to 3400 cPs for high-grade), and microbial load (absence of Salmonella in 10 g and E. coli in 5 g, with total aerobic and yeast/mold counts monitored per EU standards).^[40]^[34]^[42] Iranian export standards emphasize these parameters to meet international specifications, ensuring consistent quality for global markets.^[39]

Chemical Composition and Properties

Composition

Tragacanth gum is a complex, heterogeneous polysaccharide primarily composed of two main fractions: bassorin, which constitutes 60-70% of the gum and is the water-insoluble, swellable component, and tragacanthin, making up the remaining 30-40% as the water-soluble fraction resembling an arabinogalactan.^[43] Bassorin features a pectic structure with a backbone of (1→4)-linked α-D-galacturonic acid units, some substituted at O-3 with β-D-xylopyranosyl residues and terminal D-galactose or L-fucose groups, while tragacanthin consists of a highly branched type II arabinogalactan with (1→6)- and (1→3)-linked galactose and arabinose chains bearing side groups of (1→2)-, (1→3)-, and (1→5)-linked arabinose.^[44] Minor components include 3-4% proteins, which contribute to the gum's emulsifying properties, along with trace minerals such as calcium and magnesium that form associated cations with the polysaccharide chains.^[45] Uronic acids, particularly galacturonic acid at levels of 100-330 mg/g, impart an anionic character to the gum due to their carboxyl groups.^[44] Structurally, tragacanth gum is a highly branched heteropolysaccharide with a molecular weight of approximately 840 kDa for the whole gum, though the tragacanthin fraction has a lower molar mass of about 10⁴ Da and bassorin around 10⁵ Da.^[44] Fourier-transform infrared (FTIR) spectroscopy reveals characteristic bands for galacturonic acid, including C=O stretching at 1751 cm⁻¹ for carboxyl groups and glycosidic bonds at 1238 and 1623 cm⁻¹, while ¹H nuclear magnetic resonance (NMR) spectroscopy confirms the backbone with proton signals at 3.5-5.0 ppm for sugar residues and additional peaks indicating substitutions and branching.^[46] The composition of tragacanth gum exhibits variability depending on the Astragalus species and harvest conditions, with differences in the bassorin-to-tragacanthin ratio (ranging from 25:75 to 65:35) and monosaccharide profiles, such as higher fucose in certain species like A. compactus; root-derived exudates tend to have elevated bassorin content compared to stem or branch sources.^[44]

Physical and Chemical Properties

Tragacanth gum exhibits partial solubility in water, with approximately 30-40% of its composition—primarily the tragacanthin fraction—dissolving to form a colloidal hydrosol, while the remaining bassorin fraction swells without fully dissolving, resulting in opalescent, stiff mucilages at low concentrations of 1-5%.^[6]^[1] This behavior arises from the gum's heterogeneous polysaccharide structure, where the soluble portion disperses readily, and the insoluble portion absorbs up to 50 times its weight in water to yield highly viscous systems without complete dissolution.^[47] The polysaccharide fractions, such as tragacanthin and bassorin, underpin this solubility profile, enabling the formation of stable dispersions suitable for various functional roles. Rheologically, tragacanth gum solutions display pseudoplastic, shear-thinning behavior, with apparent viscosity decreasing under increasing shear rates, and maximum values reaching up to 3,400-3,600 cP in 1% aqueous dispersions after 24 hours at room temperature.^[6]^[48] These solutions maintain high viscosity—often exceeding 1,000 cP at typical use levels—and exhibit excellent stability across a broad pH range of 2-10, with optimal performance near pH 5, as well as thermal endurance up to 80°C without significant degradation.^[6]^[5] Additionally, the gum demonstrates strong emulsifying capacity for oil-in-water systems, providing long-term stability against coalescence and creaming even under acidic conditions or moderate salt concentrations.^[49] Its film-forming ability allows the creation of flexible, transparent barriers, while inherent biodegradability occurs through microbial enzymatic action.^[50] Analytical characterization of these properties typically involves viscosity measurements using a Brookfield viscometer, which quantifies shear-dependent flow at standardized speeds (e.g., 20-60 rpm) and concentrations to assess quality and consistency.^[51] Thermal stability is evaluated via differential scanning calorimetry (DSC), revealing an onset of decomposition above 250°C, with major exothermic transitions around 260-300°C indicating robust heat resistance before polysaccharide breakdown.^[52]^[53] These methods confirm tragacanth's functional reliability, distinguishing it as one of the most stable natural hydrocolloids.

Uses

Food Applications

Tragacanth gum serves as a versatile food additive, primarily functioning as a thickener, stabilizer, and emulsifier in various products, with typical usage levels ranging from 0.1% to 0.5% in formulations such as sauces, salad dressings, and confectionery items.^[54] In the European Union, it is designated as E413 for labeling purposes on food packaging.^[7] Its high viscosity, which develops rapidly in water to form stable gels, enables these roles by enhancing texture without altering flavor.^[51] In specific applications, tragacanth stabilizes emulsions in ice cream by preventing ice crystal formation during freezing and storage, typically at concentrations of 0.2% to 0.35%, which improves smoothness and mouthfeel.^[55] It also binds water effectively in gluten-free baking, where addition at 0.5% to 1% of flour weight enhances dough elasticity, crumb structure, and overall volume in breads and cakes made from alternative flours like buckwheat.^[56] Additionally, tragacanth suspends particles in beverages, such as flavored milks or syrup-based drinks, by forming viscous solutions that maintain uniformity and prevent sedimentation.^[57] Historically, tragacanth has been incorporated into traditional Middle Eastern sweets, such as chewy confections, where it provides binding and textural qualities in recipes dating back centuries.^[51] In modern food production, it is increasingly used in low-fat products like reduced-calorie dressings and yogurts to mimic the creaminess of full-fat versions through superior water retention and emulsion stability.^[7] Compared to synthetic thickeners, tragacanth offers advantages as a natural, plant-derived polysaccharide that is inherently halal and kosher certified, appealing to consumers seeking clean-label ingredients.^[58] Its notable heat resistance during processing, maintaining functionality across a wide temperature range, further supports its use in heat-intensive applications like baking and pasteurization without degradation.^[59]

Pharmaceutical and Medical Uses

Tragacanth serves as a versatile excipient in pharmaceutical formulations, primarily functioning as a binder in tablet production to enhance cohesion and mechanical strength of the dosage form. Typically incorporated at concentrations of 2-5% w/w, it helps prevent tablet friability during manufacturing and ensures uniform drug distribution.^[60] It also acts as a suspending agent in oral syrups, maintaining the stability of insoluble particles in liquid vehicles by increasing viscosity and preventing sedimentation.^[51] Additionally, its emulsifying properties make it suitable for stabilizing oil-in-water emulsions in topical creams, where it forms protective films around dispersed phases to improve homogeneity and shelf life.^[6] In drug delivery systems, tragacanth-based hydrogels have emerged as effective matrices for controlled release applications, leveraging their swelling behavior and biocompatibility to modulate drug kinetics. For instance, these hydrogels facilitate the encapsulation and sustained release of antibiotics such as ampicillin, achieving prolonged therapeutic levels while minimizing burst effects through pH-responsive mechanisms.^[61] Their mucoadhesive characteristics further enable prolonged contact with mucosal surfaces, making them ideal for wound dressings that promote healing by absorbing exudate and providing a barrier against infection.^[62] Recent biomedical advancements highlight tragacanth's role in tissue engineering, where it forms biocompatible scaffolds that support cellular activities essential for regeneration. Post-2020 studies have demonstrated its compatibility with human adipose-derived mesenchymal stem cells, enhancing osteogenic differentiation and extracellular matrix deposition in hydrogel constructs designed for bone repair.^[63] In targeted therapies, tragacanth coatings on nanoparticles improve site-specific delivery, as seen in magnetic hydrogel systems that enable pH- and redox-triggered release of chemotherapeutic agents directly at tumor sites, reducing systemic toxicity.^[64] Clinically, tragacanth has been incorporated into lozenges for soothing sore throats, where its demulcent action forms a protective coating on irritated mucous membranes to alleviate discomfort. The U.S. Food and Drug Administration has recognized tragacanth as generally recognized as safe (GRAS) for use in various oral pharmaceutical formulations since the mid-20th century, affirming its long-standing safety profile in such applications.^[45]^[5]

Industrial Applications

Tragacanth gum serves as a versatile natural thickener and stabilizer in various industrial sectors, leveraging its adhesive and gelling properties to enhance product performance.^[51] In the textile industry, tragacanth gum functions primarily as a sizing agent for yarns, applied in aqueous solutions to coat fibers and reduce breakage during weaving processes.^[65] Its historical application includes calico printing, where it acts as a thickener in dye preparations to ensure even color distribution on fabrics.^[4] Additionally, it serves as a hardener for textiles, improving fabric durability and handling.^[66] Within cosmetics manufacturing, tragacanth gum is employed as a thickener in formulations such as lotions, hand creams, and toothpaste, typically at concentrations of 0.4–0.8% to achieve desired viscosity and prevent phase separation.^[51] It also stabilizes hair gels, maintaining structure and emulsion integrity during product use.^[65] Beyond textiles and cosmetics, tragacanth gum finds utility as an auxiliary in leather tanning, particularly for edge slicking and polishing in vegetable-tanned processes to produce smooth, glossy finishes.^[66] In paper production, it contributes to coatings that enhance surface gloss and printability.^[51] As an adhesive, it is used in bookbinding for stiffening materials like buckram, providing a natural alternative to synthetic binders.^[67] Emerging research highlights its potential in water treatment, where tragacanth-based hydrogels effectively adsorb heavy metals from aqueous solutions, with studies demonstrating high removal efficiencies for contaminants like crystal violet and methylene blue.^[68]^[69] As of the 2020s, global production of tragacanth gum is estimated at 2000–3000 tons per year, primarily from Iran, with a significant portion allocated to industrial applications.^[70] However, demand has been moderated by substitutes such as carboxymethyl cellulose, which offers similar thickening and stabilizing effects at lower cost in sectors like textiles and adhesives.^[71]^[72]

Safety and Regulation

Toxicity and Health Effects

Tragacanth gum exhibits low acute toxicity, with oral LD50 values of 7.2–10.3 g/kg body weight in rats, mice, hamsters, and rabbits, indicating it is practically nontoxic at typical exposure levels.^[6]^[73] Studies confirm it is non-carcinogenic, as no tumors were observed in long-term animal models, including mice treated with tragacanth as a vehicle.^[74] In humans, it is non-toxic and non-allergenic at conventional doses used in food and pharmaceuticals, consistent with its affirmed Generally Recognized as Safe (GRAS) status by the FDA.^[54] Chronic exposure to tragacanth gum shows no significant adverse effects in subchronic and long-term studies, with no-observed-adverse-effect levels (NOAELs) up to 5% in the diet (approximately 5 g/kg body weight per day) in rats and baboons.^[74]^[73] Rare gastrointestinal upset, such as bloating or increased fecal output, may occur with high intake exceeding 10 g/day due to its fiber-like properties, but this is typically mild and resolves with adequate hydration.^[75] Reproductive and developmental toxicity studies in rats, mice, hamsters, and rabbits demonstrate no teratogenic effects or impacts on fertility at doses up to 6% in the diet, though maternal toxicity was noted at very high levels (e.g., 1.2 g/kg in pregnant rats).^[74]^[76] Tragacanth gum offers potential health benefits, including prebiotic effects that support gut microbiota by promoting fermentation and short-chain fatty acid production, as observed in in vitro studies with its oligosaccharide components.^[77] Additionally, it demonstrates anti-inflammatory properties in animal models, accelerating wound healing and contraction in rat skin excision studies through enhanced tissue repair and reduced inflammation.^[78] Allergenicity of tragacanth gum is minimal, with isolated reports of contact dermatitis among occupational handlers and rare hypersensitivity reactions such as asthma upon inhalation or ingestion in sensitized individuals.^[79]^[74] No cross-reactivity with gluten or latex has been documented in clinical cases.^[73]

Regulatory Status

In the United States, tragacanth gum is affirmed as generally recognized as safe (GRAS) by the Food and Drug Administration (FDA) for use as a direct food additive since 1961, in accordance with 21 CFR 184.1351.^[80] It is also approved for use in cosmetics, where the Cosmetic Ingredient Review has deemed it safe in the present practices of use.^[73] In the European Union, tragacanth gum is authorized as a food additive with the E number E413 under Regulation (EC) No 1333/2008, subject to specific purity criteria outlined in Commission Regulation (EU) No 231/2012, including a limit for heavy metals (expressed as lead) not exceeding 10 mg/kg and lead not exceeding 2 mg/kg.^[81] The maximum permitted level varies by food category but reaches 5 g/kg in fine bakery wares.^[82] Globally, the Codex Alimentarius Commission recognizes tragacanth gum as INS 413, establishing it as a permitted stabilizer, thickener, and emulsifier in various food categories, typically at levels conforming to good manufacturing practices, with purity aligned to Joint FAO/WHO Expert Committee on Food Additives specifications such as lead not exceeding 2 mg/kg.^[1] In Iran, the leading producer, export regulations mandate compliance with international purity standards to facilitate trade, ensuring the gum meets criteria like low microbial counts and minimal insoluble matter.^[83] Post-2020 assessments, including a 2021 European Food Safety Authority statement on its use as a feed additive, have reaffirmed tragacanth gum's safety profile in line with its low toxicity, supporting approvals amid rising demand for natural additives; no bans have been enacted, though sustainability labeling is increasingly encouraged for sourced materials.^[84]

References

[1]
[PDF] TRAGACANTH GUM
DEFINITION. A dried exudation obtained from the stems and branches of Astragalus gummifer Labillardiere and other Asiatic species of Astragalus (Fam.
[2]
Gum Tragacanth (GT): A Versatile Biocompatible Material beyond ...
Mar 10, 2021 · Astragalus gummifer has been previously the primary source of GT, while Astragalus microcephalus is currently considered as the major source [6] ...
[3]
Gums and resins & discussion
Gum tragacanth has been used in calico printing and for other industrial purposes. It is one of the oldest drugs and was known since 300 B.C. In modern medicine ...
[4]
Tragacanth - an overview | ScienceDirect Topics
This gum is used in the food industry as a thickener, suspender and stabilizer in various products such as ice cream, beverages, sweets, chocolate, sauces and ...
[5]
Gum Tragacanth - PubChem - NIH
Powdered exudate from Astragalus gummifer and related plants. It forms gelatinous mass in water. Tragacanth is used as suspending agent, excipient or ...
[6]
Re-evaluation of tragacanth (E 413) as a food additive - EFSA
Jun 9, 2017 · No adverse effects were reported in carcinogenicity studies at the highest dose tested and there is no concern with respect to the genotoxicity.
[7]
tragacanth - Wiktionary, the free dictionary
From Latin tragacantha, from Koine Greek τραγάκανθα (tragákantha, “tragacanth”), from Ancient Greek τράγος (trágos, “he-goat”) + ἄκανθα (ákantha, “thorn”).
[8]
TRAGACANTH definition in American English - Collins Dictionary
Word origin. C16: from French tragacante, from Latin tragacantha goat's thorn, from Greek tragakantha, from tragos goat + akantha thorn. Quick word challenge.Missing: etymology | Show results with:etymology
[9]
KATIRĀ - Encyclopaedia Iranica
Nov 20, 2015 · The English name tragacanth, derived from the Latin words tragos (goat) and acanthus (thorn), means “goat's thorn” (Webster's Dictionary). The ...
[10]
https://www.iranicaonline.org/articles/katira/
[11]
tragacanth, n. meanings, etymology and more | Oxford English ...
OED's earliest evidence for tragacanth is from 1558, in a translation by W. Ward. tragacanth is a borrowing from Latin. Etymons: Latin tragacantha, tragacanthum ...
[12]
None
Error: Could not load webpage.<|control11|><|separator|>
[13]
Plant-Based Gums and Mucilages Applications in Pharmacology ...
Mar 22, 2021 · In Iran, the tragacanth gum, popularly recognized as “Katira”, has been widely applied in medication and confectionery since ancient periods. In ...
[14]
https://pmc.ncbi.nlm.nih.gov/articles/PMC8004199/
[15]
https://doi.org/10.3390/molecules26061510
[16]
[PDF] 63400 Gum Tragacanth - Kremer Pigmente
The cheaper varieties of gum tragacanth are used in the calico printing industry, for which purpose the gum is first soaked in water for twenty-four hours ...<|separator|>
[17]
COMMERCE vii. In the Pahlavi and post-Pahlavi periods
Owing to rising wage rates, restrictions designed to prevent soil erosion, and synthetic substitutes, export products like gum tragacanth gradually became ...
[18]
[PDF] A review of recent trends in selected markets for water-soluble gums ...
the preserve of certain natural gums such as gum tragacanth, has made very ... Its use in the offshore oil industry, however, has declined greatly since the.
[19]
Astragalus gummifer Labill. - USDA Plants Database
gum tragacanth milkvetch. Classification. Kingdom. Plantae - Plants. Subkingdom. Tracheobionta - Vascular plants. Superdivision. Spermatophyta - Seed plants ...Missing: taxonomy | Show results with:taxonomy
[20]
Astragalus gummifer - Labill. - PFAF.org
Common Name, Tragacanth, Gum tragacanth milkvetch ; Family, Fabaceae or Leguminosae ; USDA hardiness, 7-10 ; Known Hazards, Many members of this genus contain ...Missing: taxonomy | Show results with:taxonomy
[21]
Stabilization of emulsions by gum tragacanth (Astragalus spp ...
The six gum tragacanth samples were exudates from the species Astragalus parrowianus, Astragalus fluccosus, Astragalus rahensis, Astragalus gossypinus, ...
[22]
Tragacanth gum - JECFA specification - CyberColloids
DEFINITION, A dried exudation obtained from the stems and branches of Astragalus gummifer Labillardiere and other Asiatic species of Astragalus (Fam.<|control11|><|separator|>
[23]
A Modern Herbal | Tragacanth - Botanical.com
Mucilage of Tragacanth has been used as anapplication to burns; it is also employed by manufacturers for stiffening calico, crape, etc. Mucilage, B.P. and ...
[24]
Physicochemical and Rheological Characterization of Gum ...
Jan 12, 2010 · The results indicated that the six species of gum tragacanth being studied in this paper exhibited significantly different physicochemical ...
[25]
Compositional analysis and rheological characterization of gum ...
The sugar composition and viscoelastic behaviour of Iranian gum tragacanth exuded by six species of Astragalus was investigated at a concentration of 1.3%
[26]
Gum Tragacanth: A Novel Biopolymer Platform for Advanced ...
Jul 21, 2025 · Gum tragacanth is sourced from the bark of Astragalus trees found in countries like Iran, Turkey, and Pakistan. The gum is collected by ...
[27]
Astragalus gummifer – Native Plant Search - PFAF.org
Tragacanth, Gum tragacanth milkvetch Astragalus gummifer native habitat is Dry sub-alpine slopes and valleys, occasionally below the tree line, 1200 - 2600 ...Missing: regions | Show results with:regions
[28]
Tragacanth | Description, Gum, Source, Uses, & Facts - Britannica
Tragacanth is second to gum arabic in commercial importance and has an ancient history of use in traditional medicine.Missing: etymology | Show results with:etymology
[29]
Tragacanth (FAO, NWFP 6) - Pl@ntUse - PlantNet
Jul 6, 2020 · Severe problems are encountered in estimating consumption of tragacanth: firstly, export data from the major producers (Iran and Turkey) are ...Missing: challenges | Show results with:challenges
[30]
Astragalus gummifer (Tragacanth) - Practical Plants
May 4, 2013 · Requires a dry well-drained soil in a sunny position. Succeeds in poor soils. Tolerates a pH in the range 3.2 to 7.8. This species is not hardy ...Missing: resistant | Show results with:resistant
[31]
https://plantuse.plantnet.org/en/Tragacanth_%28FAO%2C_NWFP_6%29
[32]
Tragacanth gum-based hydrogels for drug delivery and tissue ...
Tragacanth gum, one of many well-known gums, is regarded as a flexible substance in biomedicine. Iran is the world's top producer and exporter of Tragacanth ...
[33]
Ethnobotanical Diversity of Trees and Shrubs of Iran - ResearchGate
Jan 15, 2023 · Because of overharvesting, these species are calling a wake-up alarm for conservation. ... Astragalus gummifer . Labill. root, stem ...
[34]
https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2024.1296399/full
[35]
[PDF] Tragacanth Gum Petition.pdf - Agricultural Marketing Service
Sep 4, 2007 · Gum tragacanth is defined by JECFA as: "a dried exudation obtained from the stems and branches of Astragalus gummifer Labillardière and other ...
[36]
V. Plant gums
Trade. Iran's export of tragacanth was 91 tonnes in 1987, which with a growth rate of 56% reached 142 tonnes in 1988. The export volume further increased to ...
[37]
NFT Gums - Ancient and Modern Commercial Products
An average annual yield is 250 g/tree, although production may range from a few grams to 10 kg (NAS 1979) or 0.2 to 6.7 kg (Duke 1981). Tree improvement ...Missing: per | Show results with:per
[38]
sustainable utilization of gum and resin by improved tapping ...
A simple and safe technique of tapping with substantial increase in the yield is being developed using ethephon to enhance gum yield and wound healing.
[39]
3.4 Iran - Food and Agriculture Organization of the United Nations
Iran's export of tragacanth was 91 tonnes in 1987, increasing to 142 tonnes in 1988. The export volume further increased to 257 in 1990. Thus, there was an ...
[40]
https://www.sciencedirect.com/science/article/pii/B9780128201046000036
[41]
https://journals.sagepub.com/doi/pdf/10.3109/10915818709095487
[42]
[PDF] Final Report on the Safety Assessment of Tragacanth Gum
Traga- canth Gum was essentially nonmutagenic in a variety of mutagenic assays. Tragacanth Gum has been used as the solvent control in a carcinogenicity study.
[43]
Tragacanth – Knowledge and References - Taylor & Francis
... Astragalus gummifer, belonging to the Fabaceae family and native to western Asia. It is an excellent oil-in-water emulsifying agent with good stability to ...Missing: habitat | Show results with:habitat
[44]
[PDF] Tragacanth Gum: Structural Composition, Natural Functionality and ...
Dec 20, 2017 · The objective of this PhD study were to evaluate tragacanth samples from six species of Iranian Astragalus for their emulsion stabilizing.<|separator|>
[45]
Tragacanth Uses, Benefits & Dosage - Drugs.com
Scientific Name(s): Astragalus gummifer Labill. Common Name(s): Goat's thorn, Green dragon, Gum dragon, Gum tragacanth, Gummi tragacanthae, Hog gum, Milkvetch, ...
[46]
Periodate oxidation of tragacanth gum and evaluation of ... - Nature
Aug 18, 2025 · The molecular structure and functional groups of OTG were characterized using FTIR and ¹H NMR spectroscopy. FTIR spectra of TG and OTG ...
[47]
Tragacanth gum | 9000-65-1 - ChemicalBook
Apr 29, 2025 · Physical properties Powdered tragacanth is white to yellowish white. Gum tragacanth swells in cold water to give extremely viscous colloidal ...
[48]
[PDF] Gum Tragacanth Gels as a New Supporting Matrix for Immobilization ...
A 1% solution of GT has a viscosity of. 3600 cps at 60 rpm using a Brookfield viscometer [1 , 2]. The potential of GT as an immobilization medium, has never ...
[49]
The effect of pH and salt on the stability and physicochemical ...
Apr 20, 2016 · Emulsions stabilized with gum tragacanth show resistance to instability mechanisms when exposed to a range of salt concentrations (0–1 wt% NaCl) after 150 days ...Missing: capacity | Show results with:capacity
[50]
Biodegradation of Gum tragacanth acrylic acid based hydrogel and ...
Within 77 days, complete degradation of synthesized hydrogel was observed in the composting method, while 92.29% of degradation was observed in soil burial ...
[51]
Application of tragacanth gum as a potential food packaging film and ...
Among the many biopolymers, tragacanth gum (TG) is being explored for the production of biodegradable food packaging films. As a hydrophilic colloidal ...
[52]
Gum Tragacanth - an overview | ScienceDirect Topics
Gum Tragacanth (GT) is defined as a highly branched, anionic polysaccharide that is a biodegradable, noncarcinogenic, nontoxic, and nonallergenic natural gum, ...
[53]
[PDF] Physicochemical, rheological and structural characteristics of ...
Compositional analysis and rheological characterization of gum tragacanth ex- udates from six species of Iranian Astragalus. Food Hy- drocolloids, 25(7) ...<|control11|><|separator|>
[54]
The thermal decomposition of gum tragacanth in nitrogen
The first mass loss appears at 248 °C, which was attributed to the decomposition of tragacanthic acid as its main component. The second mass loss is at 285 °C, ...
[55]
21 CFR 184.1351 -- Gum tragacanth. - eCFR
(c) The ingredient is used in food under the following conditions: Expand Table. Maximum Usage Levels Permitted. Food (as served), Percent, Function. Baked ...
[56]
A Mini-Review on the Recent Food Applications of Major Exudates
Gum tragacanth (Concentration of 0.2 to 0.35%) was used as a stabilizer for ice cream mixtures and also ices, ice pops and sherbets, at a concentration of ∼0.5 ...
[57]
Improvement of gluten‐free bread and cake properties using natural ...
Oct 17, 2019 · Quality properties of buckwheat flour were compared with refined wheat flour, and gums (guar, acacia, xanthan, and tragacanth) were added in ...
[58]
Effect of gum tragacanth on rheological and physical properties of a ...
In this study, a flavored milk beverage was formulated using date syrup for flavoring the product and gum tragacanth to obtain an acceptable mouth feel.
[59]
Gum tragacanth - Willy Benecke
All grades are 100% natural, vegan, Halal and Kosher certified. Its use as an additive (E 413) has been approved in the EU.
[60]
Gum Tragacanth (GT): A Versatile Biocompatible Material beyond ...
Generally, GT, also known as Katira, is sourced from Central Asia and Eastern countries, and Iran is the largest producer and exporter of this natural gum [1,2] ...
[61]
[PDF] Evaluation of binder's efficiency of different natural gums in tableting ...
Tablet prepared from tragacanth were softer than acacia and gum tamarind and it was also observed that the granules binding capacity was more in case of Tam 2 ...
[62]
Novel nanohydrogel based on itaconic acid grafted tragacanth gum ...
Sep 15, 2018 · Nanohydrogel of tragacanth gum using microwave radiations is used for the controlled release of ampicillin. Tragacanth gum was grafted with ...
[63]
Synthesis and characterization of tragacanth gum derived hydrogels ...
Oct 16, 2025 · The present work focused on the design and development of tragacanth-based antibiotic drug encapsulated hydrogel wound dressings. These hydrogel ...
[64]
nano-hydroxyapatite bone tissue engineering scaffold
Osteogenic differentiation of human adipose-derived mesenchymal stem cells on gum tragacanth hydrogel. Source: Biologicals. Regulation of bone development and ...
[65]
Multi-stimuli-responsive magnetic hydrogel based on Tragacanth ...
A novel magnetic pH- and redox-responsive drug delivery system (DDS) based on natural Tragacanth gum (TG) was developed for targeted chemo/hyperthermia ...
[66]
https://www.atamanchemicals.com/tragacanth_u26230/
[67]
TRAGACANTH - Ataman Kimya
Tragacanth is used to bind aromatic substances together. Tragacanth is used as fabric stiffener and in calico printing. Tragacanth is also used as a polishing ...Missing: 19th | Show results with:19th
[68]
Making Linen Buckram: Gum Tragacanth vs Xanthan Gum
Aug 19, 2019 · Gum tragacanth is the most easily obtainable historically accurate gum for making linen buckram (less easily obtainable historical alternatives are glues based ...
[69]
Activated Carbon-Incorporated Tragacanth Gum Hydrogel ... - NIH
Dec 7, 2023 · In this study, a biocomposite hydrogel was prepared by the incorporation of activated carbon derived from pomegranate peels (PPAC) in tragacanth gum (TG).
[70]
Development of Gum Tragacanth‐Based Graft Copolymer Hydrogel ...
Sep 13, 2025 · The nanocomposite of GT was used for the adsorptive removal of MB dye [25]. The developed material adsorbed 80% of the dye from water. The ...
[71]
V. Plant gums - FAO Knowledge Repository
Current production potential is around 30,000 to 40,000 tonnes per annum, of which bulk (80%) originates in Sudan; Nigeria being the second largest producer.Missing: global | Show results with:global
[72]
Whats the Difference??? Tylose Powder…CMC Powder…Trag ...
May 12, 2009 · It is derived from purified cellulose such as cotton linters. CMC Gum helps products retain moisture. CMC Gum is a man-made gum. CMC produces ...
[73]
Tylose, Gum Tragacanth, Gum Tex- What are the differences?
Dec 5, 2017 · Tragacanth is a natural gum obtained from the dried sap of several species of Middle Eastern legumes of the genus Astragalus. To harden ...
[74]
1: Final Report on the Safety Assessment of Tragacanth Gum
In acute toxicity studies, Tragacanth Gum was practically nontoxic when administered orally to mice, rats, hamsters, and rabbits. In subchronic studies, a ...
[75]
Re‐evaluation of tragacanth (E 413) as a food additive - PMC - NIH
Jun 9, 2017 · The Panel on Food Additives and Nutrient Sources added to Food (ANS) provides a scientific opinion re‐evaluating the safety of tragacanth (E 413) as a food ...
[76]
Tragacanth - Uses, Side Effects, and More - WebMD
It is possibly safe when used as medicine. But be sure to take it with plenty of water. It can block the throat and intestines if you don't drink enough fluid.Missing: lozenges | Show results with:lozenges
[77]
606. Tragacanth Gum (WHO Food Additives Series 20) - INCHEM
Tragacanth gum is a powerful allergen capable of causing extremely severe reactions. Allergic reactions may occur as a result of inhalation or oral ingestion.Missing: definition | Show results with:definition
[78]
Developing novel synbiotic low‐fat yogurt with fucoxylogalacturonan ...
Jun 29, 2020 · Tragacanth gum (TG) displayed a prebiotic activity, but its application was restricted due to high viscosity and deterioration of organoleptic ...
[79]
Acceleration of skin wound healing with tragacanth (Astragalus ...
The results of this study clearly showed the useful effects of topical application of gum tragacanth in acceleration of skin wound contraction and healing.
[80]
f298 Tragacanth gum - Thermo Fisher Scientific
Tragacanth gum may rarely induce allergy symptoms in sensitised individuals. Asthma and contact dermatitis have been described (1-4). Excess ingestion can ...
[81]
Evidence for the safety of gum tragacanth (Asiatic Astragalus spp ...
This review collates the dietary, toxicological, immunological and chemical data available and presents the pre-requisite data concerning the 'Need' and low ...
[82]
Re‐evaluation of tragacanth (E 413) as a food additive - EFSA Journal
Jun 9, 2017 · Tragacanth is exclusively defined as a dried exudation obtained from the stems and branches of strains of Astragalus gummifer Labillardiere and ...
[83]
[PDF] B REGULATION (EC) No 1333/2008 OF THE ... - EUR-Lex
Mar 22, 2023 · ... gum, the maximum level for each is reduced proportionally. ▽M6. (25): The quantities of each of the colours E 122 and E 155 may not exceed 50 ...Missing: E413 | Show results with:E413
[84]
GSFA Online Food Additive Details for Tragacanth gum
Tragacanth gum is a food additive that is included in Table 3, and as such may be used in the following foods under the conditions of good manufacturing ...Missing: definition | Show results with:definition
[85]
Statement on the safety and efficacy of the feed additive ... - EFSA
Mar 2, 2021 · Statement on the safety and efficacy of the feed additive consisting on tragacanth gum for all animal species (Association for International ...