Gango

Perennial, Trees, Shrubs, Woody throughout, Stems erect or ascending, Stems or branches arching, spreading or decumbent, Stems greater than 2 m tall, Stems solid, Stems or young twigs glabrous or sparsely glabrate, Leaves alternate, Leaves petiolate, Stipules inconspicuous, absent, or caducous, Stipules setiform, subulate or acicular, Stipules deciduous, Stipules free, Leaves compound, Leaves even pinnate, Leaves bipinnate, Leaf or leaflet marg ins entire, Leaflets opposite, Leaflets alternate or subopposite, Leaflets 10-many, Leaves glabrous or nearly so, Inflorescences racemes, Inflorescence panicles, Inflorescence terminal, Bracts very small, absent or caducous, Flowers actinomorphic or somewhat irregular, Calyx 5-lobed, Calyx glabrous, Petals separate, Petals clawed, Petals orange or yellow, Petals bicolored or with red, purple or yellow streaks or spots, Banner petal ovoid or obovate, Wing petals narrow, oblanceolate to oblong, Wing tips obtuse or rounded, Keel tips obtuse or rounded, not beaked, Stamens 9-10, Stamens completely free, separate, Stamens long exserted, Filaments glabrous, Style terete, Fruit a legume, Fruit unilocular, Fruit indehiscent, Fruit elongate, straight, Fruit oblong or ellipsoidal, Fruit exserted from calyx, Fruit beaked, Fruit glabrous or glabrate, Fruit 3-10 seeded, Seeds ovoid to rounded in outline, Seed surface smooth, Seeds olive, brown, or black.

Biancaea sappan is a species of flowering tree in the legume family, Fabaceae, that is native to tropical Asia. Common names in English include sappanwood and Indian redwood. It was previously ascribed to the genus Caesalpinia. Sappanwood is related to brazilwood (Paubrasilia echinata), and was itself called brasilwood in the Middle Ages.

Biancaea sappan can be infected by twig dieback (Lasiodiplodia theobromae).

This plant has many uses. It has antibacterial and anticoagulant properties. It also produces a valuable reddish dye called brazilin, used for dyeing fabric as well as making red paints and inks. Slivers of heartwood are used for making herbal drinking water in various regions, such as Kerala, Karnataka and Central Java, where it is usually mixed with ginger, cinnamon, and cloves. The heartwood also contains juglone (5-hydroxy-1,4-naphthoquinone), which has antimicrobial activity. Homoisoflavonoids (sappanol, episappanol, 3'-deoxysappanol, 3'-O-methylsappanol, 3'-O-methylepisappanol and sappanone A) can also be found in B. sappan.

The wood is somewhat lighter in color than brazilwood and other related trees. Sappanwood was a major trade good during the 17th century, when it was exported from Southeast Asian nations (especially Thailand) aboard red seal ships to Japan.