Aquilaria crassna leaves extracts possess antipyretic, analgesic and anti-oxidative properties without anti-inflammatory activity. Aquilaria sinensis is a species of plant in the Thymelaeaceae family. It is endemic to China. It is threatened by habitat loss. This medicinal plant is a source of fragrant wood, formed under a pathological condition, called agarwood. According to Chinese medicinal literature, the resin can be extracted in large quantities by natural fungal infection or by external wounding (up to 5 cm into the bark). Sustainable harvesting of the resin of one tree can be induced by opening a wound 3 to 4 cm into the bark, and with the resin collected a few years later after accumulation. Or a small quantity of resin can be extracted from wood blocks by heating or burning, so that the resin liquefies and seeps from the wood blocks.  The resin is probably produced by the plant as a reaction against fungal infection or external wounding.