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 Drugs.com. Last updated on Apr 21, 2022.

Clinical Overview

Use

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.

Dosing

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

Contraindications have not been identified.

Pregnancy/Lactation

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

Interactions

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.

Toxicology

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

Scientific Family

• Sterculiaceae (Cacao)

Botany

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

History

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

Chemistry

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 ...