Garcinia hanburyi (gum resin)

Nomenclature

Garcinia hanburyi Hook. f.   Clusiaceae  
Syn. Hanbury's garcinia; Siam gamboge  
Standardized common name (English): gamboge

Botanical Voucher Specimen

Source: Royal Botanic Gardens, Kew.	Source: Royal Botanic Gardens, Kew.

Organoleptic Characteristics

Garcinia hanburyi Texture Brittle, easily powdered. Color Bright yellow. Scent Nearly odorless. Flavor Slightly acrid. Source: Schneider, A. (1921) The Microanalysis of Powdered Vegetable Drugs, 2nd ed. Garcinia hanburyi (gum resin) is odorless; taste very acrid. [...] It has no odor, and little taste, but, after remaining a short time in the mouth, produces an acrid sensation in the fauces. Source: United States Dispensatory (1918)

Macroscopic Characteristics

In hard, brittle, cylindrical pieces, usually hollow in the center, from 2 to 5 cm. in diameter, from 10 to 20 cm in length, externally grayish-orange-brown, longitudinally striate; fracture conchoidal, smooth, orange-red. When rubbed with water it yields a yellow emulsion which becomes darker and almost transparent upon the addition of ammonia water. The emulsion turns green upon the addition of iodine T.S. (starch). Source: United States Dispensatory (1918)

Microscopic Characteristics

The official description is [in part] as follows: "The powder is bright yellow, containing few or no starch grains. When mounted in hydrated chloral T.S. and examined under the microscope the particles, for the most part, slowly dissolve, leaving scattered fragments of vegetable tissues. Not less than 65 per cent. of Gamboge is soluble in alcohol." U.S. Source: United States Dispensatory (1918) The microscope reveals little that is characteristic. Fragments of vegetable tissue are sparingly present. There is no starch present. The emulsified particles resemble bacteria and show active Brownian movement. Source: Schneider, A. (1921) The Microanalysis of Powdered Vegetable Drugs, 2nd ed. Source: Schneider, A. (1921) The Microanalysis of Powdered Vegetable Drugs, 2nd ed.