Category: Medicines - plant based
Introduction and description
Styrax is a genus of about 130 species of large shrubs or small trees in the family Styracaceae. Common names include snowbell, styrax, and the more ambiguous storax and benzoin. The spicebush (Lindera benzoin) is a different plant, in the family Lauraceae.
It is principally known for its resin. Benzoin resin is a balsamic resin obtained from the bark of several species of trees in the genus Styrax. Benzoin resin is the dried exudation from the pierced bark. Commonly called "benzoin", it is called "benzoin resin" to distinguish it from the chemical compound benzoin. Benzoin is also called gum benzoin or gum benjamin, but "gum" is incorrect as benzoin is not a polysaccharide. Its name came via the Italian from the Arabic lubān jāwī (لبان جاوي, "frankincense from Java").
Benzoin resin is used in perfumes, some kinds of incense, as a flavouring, and medicine [of which more shortly]. It is a common ingredient in incense-making and perfumery because of its sweet vanilla-like aroma and fixative properties. It is found in the church incense used in Russia and some other Orthodox Christian societies, as well as Western Catholic Churches. It is also used in Arab States of the Persian Gulf and India, where it is burned on charcoal as an incense.
Benzoin resin is also used in blended types of Japanese incense, Indian incense, Chinese incense (known as Anxi xiang; 安息香), and Papier d'Arménie as well as incense sticks. It is also used in the production of Bakhoor (Arabic بخور - scented wood chips) as well as various mixed resin incense in the Arab countries and the Horn of Africa.
In perfumery, benzoin is used as a fixative, slowing the dispersion of essential oils and other fragrance materials into the air. Benzoin resin is used in cosmetics, veterinary medicine, and scented candles. It is used as a flavoring in alcoholic and nonalcoholic beverages, baked goods, chewing gum, frozen dairy, gelatins, puddings, and soft candy.
Styrax are very attractive trees. Several species of styrax are popular ornamental trees in parks and gardens, especially S. japonicus and its cultivars like 'Emerald Pagoda', and Styrax obassia.
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).
The wood of the larger species has been used for fine handicrafts. That of egonoki (エゴノキ, S. japonicus) is used to build kokyū (胡弓), the Japanese bowed instrument. But this has caused problems as styrax species have declined in numbers due to unsustainable logging and habitat degradation. While most of the speciese are classified as Vulnerable by the IUCN, only four trees of the nearly extinct palo de jazmin (S. portoricensis) are known to survive at a single location. Although legally protected, this species could be wiped out by a single hurricane.
Styrax is 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.
Types of Resin
There are two common kinds of benzoin resin, benzoin Siam and benzoin Sumatra. Benzoin Siam is obtained from Styrax tonkinensis, found across Thailand, Laos, Cambodia, and Vietnam. Benzoin Sumatra is obtained from Styrax benzoin, which grows predominantly on the island of Sumatra. Unlike Siamese benzoin, Sumatran benzoin contains cinnamic acid in addition to benzoic acid. In the United States, Sumatra benzoin (Styrax benzoin and Styrax paralleoneurus) is more customarily used in pharmaceutical preparations, Siam benzoin (Styrax tonkinensis et al.) in the flavor and fragrance industries.
Styrax resin has been used in perfumes, certain types of incense, and medicines since antiquity. There is some degree of uncertainty as to exactly what resin old sources refer to. Turkish sweetgum (Liquidambar orientalis) is an unrelated tree in the family Altingiaceae that produces a similar resin traded in modern times as storax or as "Levant styrax,". Liquidamabar is also on the site.
Nevertheless it is clear that at least some of the resin traded in ancient times was not Turkish sweetgum but Styrax. The Ancient Greeks and the Ancient Romans used ‘sweetgum’, some of which may have been Styrax resin, probably from S. officinalis, and imported in quantity from the Near East by Phoenician merchants. Herodotus of Halicarnassus in the 5th century BC indicated that different kinds of "storax" were traded.
The nataf (נטף) of the incense sacred to Yahweh, mentioned in the Book of Exodus, is loosely translated by the Greek term staktē (στακτή, AMP: Exodus 30:34), or an unspecific "gum resin" or similar term (NIV: Exodus 30:34). Nataf may have meant the resin of Styrax officinalis
Styrax resin from southern Arabian species was once burned during frankincense (Boswellia resin) harvesting; it was said to drive away snakes:
Herodotus of Halicarnassus (c.440 BC) III.107.2:
[The Arabians] gather frankincense by burning that storax which Phoenicians carry to Hellas; they burn this and so get the frankincense; for the spice-bearing trees are guarded by small winged snakes of varied color, many around each tree; these are the snakes that attack Egypt. Nothing except the smoke of storax will drive them away from the trees."
Since the Middle Ages, Southeast Asian benzoin resins became increasingly available; today there is sadly little international trade in S. officinalis resin and little production of Turkish sweetgum resin due to that species' decline in numbers.
There has been little dedicated research into the medical properties of styrax resin, but it has been used for long, and apparently with favorable results. It was important in Islamic medicine; Avicenna (Ibn Seena, ابن سینا) discusses S. officinalis in his Al-Qanun fi al-Tibb (القانون في الطب, The Law of Medicine). He indicates that styrax resin mixed with other antibiotic substances and hardening material gives a good dental restorative material. Benzoin resin is a component of the "Theriaca Andromachi Senioris", a Venice treacle recipe in the 1686 d'Amsterdammer Apotheek.
The resin is still to be found in Friar's Balsam, which contains Cape aloes and storax (liquidambar resin) along with Benzoin resin from the bark of several species of trees in the genus Styrax. It was invented by Dr Joshua Ward around 1760. It was and is used as an inhalant. It is inhaled in steam as a treatment for various conditions including bronchitis and colds. It is also used for a variety of nose problems including sinusitis, as its bacterial action helps to fight the bacterial infection.
Tincture of benzoin is benzoin resin dissolved in alcohol. Today tincture of benzoin is most often used in first aid for small injuries, as it acts as a disinfectant and local anaesthetic and seems to promote healing. Benzoin resin and its derivatives are also used as additives in cigarettes.
The antibiotic activity of benzoin resin seems mostly due to its abundant benzoic acid and benzoic acid esters, which were named after the resin; other less well known secondary compounds such as lignans like pinoresinol are likely significant too.
- Dr Duke's list of Chemicals and their Biological Activities in: Styrax benzoin DRYANDER (Styracaceae) -- Benzoin, Onycha, Styrax 020252