Gurjun balzam

The essential oil obtained from the oleoresin is called gurjun balsam. The oleoresin obtained from the sapwood of Dipterocarpus is known as minyak keruing, damar minyak, minyak lagan or balau. Dipterocarpus turbinatus, commonly known as gurjan or gurjun, is a species of tree native to north-eastern India and mainland Southeast Asia. The trees of D. turbinatus are lofty, growing 30-45 m tall. The resin of the tree is used in India, where it is the source of kanyin oil and gurjun oil. Dipterocarpus tuberculatus, from Bangladesh, Burma (Myanmar), Indo-China and Thailand, is another important species yielding gurjun balsam. Dipterocarpus turbinatus is an important source of the wood known as keruing, and is often used in the plywood industry. The conservation status of Dipterocarpus turbinatus is Vulnerable, and the major threat for the species is habitat loss.

The essential oil is not a balsam in the strict sense, as it does not contain any cinnamic or benzoic acid. The essential oils from Dipterocarpus are composed almost exclusively of sesquiterpene hydrocarbons. As such they resemble copaiva balsam from South American Copaifera species and have also been known as East Indian copaiva balsam. The essential oil of Dipterocarpus kerrii oleoresin harvested by bark chipping contains 79% α-gurjunene, 5.3% allo-aromadendrene, 1.1% β-caryophyllene and 0.8% β-gurjunene. The essential oil from traditionally harvested oleoresin contains 58% α-gurjunene and 4.1% allo-aromadendrene. The essential oil of Dipterocarpus grandiflorus is soluble in common solvents except ethanol. The oil of Dipterocarpus grandiflorus contains 50-95% allo-aromadendrene and 3-20% α-gurjunene. The essential oil of Dipterocarpus gracilis is composed of 75% β-caryophyllene and 25% α-humulene. The balsam contains 40 to 70 per cent of a volatile oil that is similar to oil of copaiba in composition. Besides the volatile oil, the balsam contains crystalline gurjunic acid, resin and a bitter principle. The resinous fraction of the oleoresin contains 10-40% dipterocarpol, a triterpenoid. Alpha-gurjunene has the molecular formula C₁₅H₂₄ and a molecular weight of 204.35. The compounds α-gurjunene, allo-aromadendrene, humulene and caryophyllene have termiticidal properties.

The oleoresin is still traditionally used for illumination, to caulk boats, to make baskets watertight and to treat timber which is exposed to the weather. It is now used for interior varnishing, and in medicine as disinfectant, laxative, diuretic, mild stimulant, and in analgesic liniments. As a natural varnish it produces a brilliant, tough, and durable coating, but it is slow-drying and becomes brittle over time. In Cambodia, the almost solid resin is especially used to prepare torches. In herbal medicine, the plant has been traditionally used for treating gonorrhea, leprosy, psoriasis, and other skin diseases.

—

Related: Amberwood · Andiroba · Bakhoor · Balsamic Notes · Benzoin Resinoid · Benzyl Benzoate · Benzyl Salicylate · Birch Tar