Concept

Styrax

Styrax (common names storax or snowbell) is a genus of about 130 species of large shrubs or small trees in the family Styracaceae, mostly native to warm temperate to tropical regions of the Northern Hemisphere, with the majority in eastern and southeastern Asia, but also crossing the equator in South America. The resin obtained from the tree is called benzoin or storax (not to be confused with the Liquidambar storax balsam). The genus Pamphilia, sometimes regarded as distinct, is now included within Styrax based on analysis of morphological and DNA sequence data. The spicebush (Lindera benzoin) is a different plant, in the family Lauraceae. Styrax trees grow to 2–14 m tall, and have alternate, deciduous or evergreen simple ovate leaves 1–18 cm long and 2–10 cm broad. The flowers are pendulous, with a white 5–10-lobed corolla, produced 3–30 together on open or dense panicles 5–25 cm long. The fruit is an oblong dry drupe, smooth and lacking ribs or narrow wings, unlike the fruit of the related snowdrop trees (Halesia) and epaulette trees (Pterostyrax). Benzoin resin, a dried exudation from pierced bark, is currently produced from various Styrax species native to Sumatra, Java, and Thailand. Commonly traded are the resins of S. tonkinensis (Siam benzoin), S. benzoin (Sumatra benzoin), and S. benzoides. The name benzoin is probably derived from Arabic lubān jāwī (لبان جاوي, "Javan frankincense); compare the obsolete terms gum benjamin and benjoin. This incidentally shows that the Arabs were aware of the origin of these resins, and that by the late Middle Ages at latest international trade in them was probably of major importance. The chemical benzoin (2-hydroxy-2-phenylacetophenone), despite the apparent similarity of the name, is not contained in benzoin resin in measurable quantities. However, benzoin resin does contain small amounts of the hydrocarbon styrene, named however for Levant storax (from Liquidambar orientalis), from which it was first isolated, and not for the genus Styrax itself; industrially produced styrene is now used to produce polystyrene plastics, including Styrofoam.

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