Skip to main content

Karaya Gum

Scientific Name(s): Sterculia urens Roxb.
Common Name(s): Bassora tragacanth, Indian chestnut, Indian tragacanth, Kadaya, Kadira, Karaya, Katila, Kullo, Mucara, Sterculia

Medically reviewed by Last updated on Apr 21, 2022.

Clinical Overview


Karaya gum is used in cosmetics and food as well as in pharmaceuticals as a laxative and adhesive. Extracts of the seeds and bark of related Sterculia species have been investigated for hypocholesterolemic and anti-inflammatory effects in animals.


No specific dosage of karaya gum preparations has been determined by clinical studies. Studies conducted in the 1980s used doses of 10 g/day.


Contraindications have not been identified.


Information regarding safety and efficacy in pregnancy and lactation is lacking.


None well documented.

Adverse Reactions

Aside from allergy, case reports of adverse reactions are lacking; however, excessive doses as a laxative may cause diarrhea, and, with inadequate water consumption, may result in bowel obstruction.


Karaya gum is generally recognized as safe (GRAS) by the US Food and Drug Administration.

Scientific Family

  • Sterculiaceae (Cacao)


The majority of commercial karaya gum is obtained from S. urens, a soft-wood tree that grows to approximately 10 m. The small, yellow flowers bloom from February to March, and the tree bears a star-shaped fruit.1, 2

The plant is native to India and Pakistan, where it is found on the dry, rocky hills and plateaus and is cultivated for karaya production.3 All parts of the tree exude a soft gum when injured. Karaya gum is produced by charring or scarring the tree trunk and removing a piece of bark or by drilling holes into the trunk. The gum seeps from the scars and is collected, washed, dried, and then graded. A mature tree may yield 1 to 5 kg of gum per season.1, 3, 4


Karaya gum has been used commercially for approximately 100 years. Its use became widespread during the early 20th century, when it was used as an adulterant or as an alternative to tragacanth gum.3 However, experience indicated that karaya possessed certain physiochemical properties that made it more useful than tragacanth and less expensive. Traditionally, India has been the largest producer and exporter of karaya gum.3 The gum has been used in a variety of products, including cosmetics and lotions, and as a bulking agent.5 The fruit of the related Sterculia villosa has been used traditionally as an antidiabetic agent in India.6


Karaya gum is a complex, partially acetylated polysaccharide obtained as a calcium and magnesium salt. The polysaccharide component of karaya has a high molecular weight and is composed of galacturonic acid, beta-D-galactose, glucuronic acid, L-rhamnose, and other residues.1, 2

The quality of karaya gum depends on the thoroughness of impurity removal. Food-grade gum is usually a white to pinkish-gray powder with a slight vinegar odor from acetic acid released during storage.1 Pharmaceutical grades of karaya may be almost clear or translucent.2

Karaya gum is the least soluble of commercial plant exudates, but it absorbs water rapidly and swells to form viscous colloidal solutions even at low concentrations (1%).1 The swelling reaction of karaya gum is dependent upon the presence of acetyl groups in its structure. Deacetylation through alkali treatment results in a water soluble gum. When used in higher concentrations in water (up to 4%), karaya forms gels or pastes. Unlike other gums, karaya swells in 60% alcohol but remains insoluble in other organic solvents. Karaya may absorb up to 100 times its weight in water.1

The astringent bark, containing alpha cellulose, botulin, and tannin, has also been investigated.2, 7 Sesquiterpenoids possessing antiproliferative properties have been identified in the bark of the related Madagascan species Sterculia tavia.8

In addition, seeds of the karaya plant contain carbohydrates and lignoceric, linoleic, myrstic, oleic, palmitic, and stearic acids.7 Cerebroside chemicals, with antioxidant properties, and polysaccharides have been identified in the related species Sterculia lychnophora, that is used in traditional Chinese medicine,9, 10 whereas lectins have been identified in Serissa foetida seeds.11

Uses and Pharmacology

Anti-inflammatory effects

Animal data

Extracts of S. lychnophora10 seeds and Sigara striata12 bark were effective in reducing ear and paw edema and writhing in mice.

Clinical data

There are no clinical data regarding the use of extracts of Sterculia species for anti-inflammatory effects.


Animal data

Limited studies in hens and quails suggest karaya saponin may exert a hypocholerstolemic effect.13, 14

Clinical data

No clinical data exist regarding the use of karaya extracts for the management of dyslipidemia. Earlier preliminary studies suggested that gums may normalize blood sugar and plasma lipid levels.15


Animal data

There are no recent animal data regarding the use of karaya gum as a laxative. Studies were conducted in dogs in the 1930s.16

Clinical data

Karaya gum particles absorb water and swell to 60 to 100 times their original volume, making it useful as a bulk laxative.1, 3, 17 Excessive doses as a laxative may cause diarrhea and, with inadequate water consumption, may result in bowel obstruction.18 Recent clinical data is lacking.

Other uses

Karaya gum has also been used as an adhesive for dental fixtures. A protective coating of karaya gum applied to dentures has been shown to reduce bacterial adhesion by 98%.19

The gum has been used in ostomy care, as a base for transdermal delivery of medicines,20, 21 and as a carrier for poorly soluble medicines.22, 23 Similarly, the gum has been tested as a biosorbent of toxic heavy metal ions.24

Antiproliferative properties of the bark of the related Madagascan S. tavia plant have been described,8 whereas antioxidant properties have been identified in the related plant S. lychnophora, used in traditional Chinese medicine.9 Antimicrobial activity against human pathogens was demonstrated by lectins extracted from the seeds of S. foetida.11


No specific dosage of karaya gum preparations has been determined by clinical studies. Studies conducted in the 1980s used doses of 10 g/day.16

Pregnancy / Lactation

Information regarding safety and efficacy in pregnancy and lactation is lacking.


None well documented. Use with antiperistalsis agents (eg, loperamide) is unadvisable.1

Adverse Reactions

A report published in 1989 found that widespread use of karaya gum throughout the United States and Europe was not associated with any clinically important adverse experiences.25 Aside from allergy,16 case reports of adverse reactions with the use of karaya gum are limited; however, excessive doses as a laxative may cause diarrhea and, with inadequate water consumption, may result in bowel obstruction.18


Karaya gum is GRAS for internal consumption.25 Studies conducted in the 1970s and 1980s found no evidence of mutagenicity or teratogenicity.16


1. Khan I, Abourashed E. Leung’s Encyclopedia of Common Natural Ingredients Used in Food, Drugs, and Cosmetics. 3rd Ed. Hoboken, NJ: Wiley; 2009.
2. Morton JF. Major Medicinal Plants. Springfield, IL: CC Thomas; 1977.
3. Verbeken D, Dierckx S, Dewettinck K. Exudate gums: occurrence, production, and applications. Appl Microbiol Biotechnol. 2003;63(1):10-21.12802529
4. Sterculia urens Roxb. sterculia. USDA, NRCS. 2014. The PLANTS Database (, 8 December 2014). National Plant Data Center, Greensboro, NC 27401-4901 USA. Accessed December 8, 2014.
5. Der Marderosian AH, Liberti LE. Natural Product Medicine: A Scientific Guide to Food, Drugs, Cosmetics. Philadelphia, PA: GF Stickley Co; 1988.
6. Tarak D, Namsa ND, Tangjang S, et al. An inventory of the ethnobotanicals used as anti-diabetic by a rural community of Dhemaji district of Assam, Northeast India. J Ethnopharmacol. 2011;138(2):345-350.21871548
7. Duke JA. Handbook of Biologically Active Phytochemicals and Their Activities. Boca Raton, FL: CRC Press Inc; 1992.
8. Dai Y, Harinantenaina L, Brodie PJ, et al. Isolation and synthesis of two antiproliferative calamenene-type sesquiterpenoids from Sterculia tavia from the Madagascar rain forest. Bioorg Med Chem. 2012;20(24):6940-6944.23149304
9. Wang RF, Wu XW, Geng D. Two cerebrosides isolated from the seeds of Sterculia lychnophora and their neuroprotective effect. Molecules. 2013;18(1):1181-1187.23344207
10. Ai L, Wu J, Che N, Wu Y, Cui SW. Extraction, partial characterization and bioactivity of polysaccharides from boat-fruited sterculia seeds. Int J Biol Macromol. 2012;51(5):815-818.22910576
11. Braga AA, E Lacerda RR, de Vasconcelos Medeiros GK, et al. Antibacterial and hemolytic activity of a new lectin purified from the seeds of Sterculia foetida L. Appl Biochem Biotechnol. 2014;175(3):1689-1699.25422058
12. Silva FV, Oliveira IS, Figueiredo KA, et al. Anti-inflammatory and antinociceptive effects of Sterculia striata A. St.-Hil. & Naudin (Malvaceae) in rodents. J Med Food. 2014;17(6):694-700.24476221
13. Afrose S, Hossain MS, Tsujii H. Effect of dietary karaya saponin on serum and egg yolk cholesterol in laying hens. Br Poult Sci. 2010;51(6):797-804.21161787
14. Afrose S, Hossain MS, Tsujii H. Hypocholesterolemic effect of karaya saponin in Japanese laying quails (Coturnix coturnix japonica). J Anim Physiol Anim Nutr (Berl). 2011;95(6):693-700.21114549
15. Behall KM. Effect of soluble fibers on plasma lipids, glucose tolerance and mineral balance. Adv Exp Med Biol. 1990;270:7-16.1964020
16. Karaya Gum (Sterculia). International Programme in Chemical Safety INCHEM. Accessed December 8, 2014.
17. Meier P, Seiler WO, Stahelin HB. Bulk-forming agents as laxatives in geriatric patients [in German]. Schweiz Med Wochenschr. 1990;120(9):314-317.2156337
18. Duke J, Bogenschutz-Godwin M, duCellier J, Duke P. Handbook of Medicinal Herbs. 2nd ed. Boca Raton, FL: CRC Press; 2002.
19. Wilson M, Harvey W. Prevention of bacterial adhesion to denture acrylic. J Dent. 1989;17(4):166-170.2768628
20. Evans WC. Trease and Evans' Pharmacognosy. 13th ed. London, England: Bailliere Tindall; 1989.
21. Bart BJ, Biglow J, Vance JC, Neveaux JL. Salicylic acid in karaya gum patch as a treatment for verruca vulgaris. J Am Acad Dermatol. 1989;20(1):74-76.2643641
22. Munday DL, Cox PJ. Compressed xanthan and karaya gum matrices: hydration, erosion and drug release mechanisms. Int J Pharm. 2000;203(1-2):179-192.10967440
23. Murali Mohan Babu GV, Prasad ChD, Ramana Murthy KV. Evaluation of modified gum karaya as carrier for the dissolution enhancement of poorly water-soluble drug nimodipine. Int J Pharm. 2002;234(1-2):1-17.11839433
24. Vellora Thekkae Padil V, Rouha M, Cernik M. Hydrocolloid-stabilized magnetite for efficient removal of radioactive phosphates. Biomed Res Int. 2014;2014:504760.24696854
25. Anderson DM. Evidence for the safety of gum karaya (Sterculia spp.) as a food additive. Food Addit Contam. 1989;6(2):189-199.2647531


This information relates to an herbal, vitamin, mineral or other dietary supplement. This product has not been reviewed by the FDA to determine whether it is safe or effective and is not subject to the quality standards and safety information collection standards that are applicable to most prescription drugs. This information should not be used to decide whether or not to take this product. This information does not endorse this product as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this product. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this product. This information is not specific medical advice and does not replace information you receive from your health care provider. You should talk with your health care provider for complete information about the risks and benefits of using this product.

This product may adversely interact with certain health and medical conditions, other prescription and over-the-counter drugs, foods, or other dietary supplements. This product may be unsafe when used before surgery or other medical procedures. It is important to fully inform your doctor about the herbal, vitamins, mineral or any other supplements you are taking before any kind of surgery or medical procedure. With the exception of certain products that are generally recognized as safe in normal quantities, including use of folic acid and prenatal vitamins during pregnancy, this product has not been sufficiently studied to determine whether it is safe to use during pregnancy or nursing or by persons younger than 2 years of age.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.