The trees start producing resin at about eight to 10 years old. Tapping is done two to three times per year with the final taps producing the best tears because of their higher aromatic terpene, sesquiterpene and diterpene content. Generally speaking, the more opaque resins are the best quality. Cheap resin is produced in the Horn of Africa, which is the Roman Catholic Church's major source.
Boswellia bhaw-dajiana (older spelling Boswellia bhau-dajiana): Horn of Africa.: 487 It is a synonym of Boswellia sacra
Boswellia carteri (older spelling Boswellia carterii): Horn of Africa, Nubia.: 10 It was long considered an independent species,: 138 but in the 1980s it was determined to be a synonym of Boswellia sacra.
Boswellia frereana: Horn of Africa.: 10 The resin is less bitter and the fragrance of incense is less "heavy" than Boswellia sacra.: 497 Contains no boswellic acids.: 19
Other notable species:
Boswellia occulta: Horn of Africa. In 2019, it was discovered that Somali harvesters considered Boswellia occulta to be the same species with Boswellia carteri even though their shapes are different, and sold resins from both species as the same thing. However, the chemical compositions of their essential oils are completely different.
Recent studies indicate that frankincense tree populations are declining, partly from overexploitation. Heavily tapped trees produce seeds that germinate at only 16% while seeds of trees that had not been tapped germinate at more than 80%. In addition, burning, grazing, and attacks by the longhorn beetle have reduced the tree population. Conversion (clearing) of frankincense woodlands to agriculture is also a major threat.
Structure of β-boswellic acid, one of the main active components of frankincense
These are some of the chemical compounds present in frankincense:
acid resin (6%), soluble in alcohol and having the formula C20H32O4
Frankincense was reintroduced to Western Europe by Frankish Crusaders, and other Western Europeans on their journeys to the Eastern Roman Empire where it was commonly used in church services. Although named frankincense, the name refers to the quality of incense brought to Western Europe, not to the Franks themselves.
Southern Arabia was an exporter of frankincense in antiquity, with some of it being traded as far as China. The 13th-century Chinese writer and customs inspector Zhao Rugua wrote that Ruxiang or xunluxiang (Chinese: 乳香rǔ xiāng/ 薰陸香xūn lù xiāng) comes from the three Dashi states (Chinese: 大食dàshí - Caliphate (Arab Muslims)) of Maloba (Murbat), Shihe (Shihr), and Nufa (Dhofar), from the depths of the remotest mountains; the trunk of the tree is notched with a hatchet, upon which the resin flows out, and, when hardened, turns into incense, which is gathered and made into lumps; it is transported on elephants to the Dashi ports, then on ship to Sanfoqi; which is why it was known as a product of Sanfoqi.
Thousands of tons of frankincense are traded every year to be used in religious ceremonies as incense in thuribles and by makers of perfumes, natural medicines, and essential oils. It can be inhaled or applied to the skin for its supposed health benefits. In the Horn of Africa, frankincense is harvested in the Bari and Sanaag regions: mountains lying at the northwest of Erigavo; El Afweyn District; Cal Madow mountain range, a westerly escarpment that runs parallel to the coast; Cal Miskeed, including Hantaara and Habeeno plateau and a middle segment of the frankincense-growing escarpment; Karkaar mountains or eastern escarpment, which lies at the eastern fringe of the frankinscence escarpment. In Dhofar, Oman, frankincense species grow north of Salalah and were traded in the ancient coastal city of Sumhuram, now Khor Rori.
In 1998, the International Union for Conservation of Nature warned that one of the primary frankincense species, Boswellia sacra, is "near threatened". Frankincense trees are not covered by the Convention on International Trade in Endangered Species of Wild Fauna and Flora, but experts argue that Boswellia species meet the criteria for protection. In a 2006 study, an ecologist at Wageningen University & Research claimed that, by the late-1990s, Boswellia papyrifera trees in Eritrea were becoming hard to find. In 2019, a new paper predicted a 50% reduction in Boswellia papyrifera within the next two decades. This species, found mainly in Ethiopia, Eritrea, and Sudan, accounts for about two-thirds of global frankincense production. The paper warns that all Boswellia species are threatened by habitat loss and overexploitation. Most Boswellia grow in harsh, arid regions beset by poverty and conflict. Harvesting and selling the tree's resin is one of the only sources of income for the inhabitants, resulting in overtapping.
The use of Boswellia resin for spiritual and medicinal purposes dates back to ancient civilizations. Numerous compounds of different chemical categories are identified in the resin; the pharmacological actions of Boswellia resin are attributed to the complementary effects exerted by these compounds. Clinical studies have demonstrated the effectiveness of frankincense resin in some disease conditions like asthma, rheumatoid arthritis, inflammatory bowel diseases, osteoarthritis, and relapsing-remitting multiple sclerosis. The essential oil obtained from the oleogum resin of Boswellia serrata showed antimicrobial activities. Also, in vivo studies on animals revealed that frankincense oleogum resin exhibits neuroprotective activity.
Frankincense is often prepared inside a censer, such as the meerschaumdabqaad traditionally used in Horn of Africa.
The Egyptians cleansed body cavities in the mummification process with frankincense and natron. In Persian medicine, it is used for diabetes, gastritis and stomach ulcer. The oil is used in Abrahamic religions to cleanse a house or building of bad or evil energy—including used in exorcisms and to bless one's being (like the bakhoor commonly found in Persian Gulf cultures by spreading the fumes towards the body).
In traditional Chinese medicine, frankincense (Chinese: 乳香rǔ xiāng) along with myrrh (沒藥mò yào) are considered to have anti-bacterial properties and blood-moving uses. It can be used topically or orally, also used in surgical and internal medicine of traditional Chinese medicine. It is used to relieve pain, remove blood stasis, promote blood circulation and treat deafness, stroke, locked jaw, and abnormalities in women's menstruation.
The essential oil of frankincense is produced by steam distillation of the tree resin. The oil's chemical components are 75% monoterpenes, sesquiterpenes, and ketones. Contrary to some commercial claims, steam distilled frankincense oils do not contain the insufficiently volatile boswellic acids (triterpenoids), although they may be present in solvent extractions. The chemistry of the essential oil is mainly monoterpenes and sesquiterpenes, such as alpha-pinene, Limonene, alpha-Thujene, and beta-Pinene with small amounts of diterpenoid components being the upper limit in terms of molecular weight.
Essential oils can be diluted and applied to skin or the frangrance can be inhaled.
^Kauz R (2010). Aspects of the Maritime Silk Road: From the Persian Gulf to the East China Sea. Otto Harrassowitz Verlag. p. 130. ISBN978-3-447-06103-2. Retrieved December 26, 2011. The frankincense was first collected in the Hadhramaut ports of Mirbat, Shihr, and Zufar whence Arab merchant vessels shipped it to Srivijaya, before it was then reexported to China. The term "xunluxiang" derives from the Arab word "kundur". . . According to Li Xun, frankincense originally came from Persia. Laufer refers to the Xiangpu 香譜 by Hong Chu . . . Zhao Rugua notes: Ruxiang or xunluxiang comes from the three Dashi countries of Murbat (Maloba), Shihr (Shihe), and Dhofar (Nufa), from the depths of the remotest mountains. The tree which yields this drug may generally be compared to the pine tree. Its trunk is notched with a hatchet, upon which the
^Kauz R (2010). Ralph Kauz (ed.). Aspects of the Maritime Silk Road: From the Persian Gulf to the East China Sea. Otto Harrassowitz Verlag. p. 131. ISBN978-3-447-06103-2. Retrieved December 26, 2011. resin flows out, and, when hardened, turns into incense, which is gathered and made into lumps. It is transported on elephants to the Dashi (on the coast), who then load it upon their ships to exchange it for other commodities in Sanfoqi. This is the reason why it is commonly collected at and known as a product of Sanfoqi.
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