Frankincense

Description

Frankincense is tapped from the scraggy but hardy trees by slashing the bark, which is called striping, and allowing the exuded resin to bleed out and harden. These hardened resins are called tears. There are several species and varieties of frankincense trees, each producing a slightly different type of resin. Differences in soil and climate create even more diversity of the resin, even within the same species. Boswellia sacra trees are considered unusual for their ability to grow in environments so unforgiving that they sometimes grow out of solid rock. The initial means of attachment to the rock is unknown, but is accomplished by a bulbous disk-like swelling of the trunk. This growth prevents it from being ripped from the rock during violent storms. This feature is slight or absent in trees grown in rocky soil or gravel. The trees start producing resin when they are about eight to 10 years old. Tapping is done two to three times a year with the final taps producing the best tears due to their higher aromatic terpene, sesquiterpene and diterpene content. Generally speaking, the more opaque resins are the best quality. Fine resin is produced in Somalia, from which the Roman Catholic Church purchases most of its stock.

Recent studies have indicated that frankincense tree populations are declining, partly due to over-exploitation. 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.

History

Frankincense has been traded on the Arabian Peninsula, in North Africa, and Somalia for more than 5000 years. A mural depicting sacks of frankincense traded from the Land of Punt adorns the walls of the temple of ancient Egyptian Queen Hatshepsut, who died circa 1458 BC.

Frankincense was one of the consecrated incenses (HaKetoret) described in the Hebrew Bible and Talmud used in Ketoret ceremonies. The frankincense of the Jews, as well as of the Greeks and Romans, is also called Olibanum (from the Hebrew חלבנה). Old Testament references report it in trade from Sheba (Isaiah 60:6 ; Jeremiah 6:20). Frankincense is mentioned in the Song of Solomon (Song of Solomon 4:14).

It was offered on a specialized incense altar in the time when the Tabernacle was located in the First and Second Jerusalem Temples. The ketoret was an important component of the Temple service in Jerusalem. It is mentioned in the Hebrew Bible book of Exodus 30:34, where it is named levonah (lebonah in the Biblical Hebrew), meaning "white" in Hebrew. It was one of the ingredients in the perfume of the sanctuary (Exodus 30:34), and was used as an accompaniment of the meal-offering (Leviticus 2:1, 2:16, 6:15, 24:7). When burnt it emitted a fragrant odour, and the incense was a symbol of the Divine name (Malachi 1:11 ; Song of Solomon 1:3) and an emblem of prayer (Psalm 141:2 ; Luke 1:10 ; Revelation 5:8, 8:3). It was often associated with myrrh (Song of Solomon 3:6, 4:6) and with it was made an offering to the infant Jesus (Matthew 2:11). A specially "pure" kind, lebhonah zakkah, was presented with the showbread (Leviticus 24:7).

Frankincense was reintroduced to Europe by Frankish Crusaders, although its name refers to its quality, not to the Franks themselves. Although it is better known as "frankincense" to westerners, the resin is also known as olibanum, in Arabic al-lubān (roughly translated: "that which results from milking"), a reference to the milky sap tapped from the Boswellia tree.

The lost city of Ubar, sometimes identified with Irem in what is now the town of Shisr in Oman, is believed to have been a centre of the frankincense trade along the recently rediscovered "Incense Road". Ubar was rediscovered in the early 1990s and is now under archaeological excavation.

The Greek historian Herodotus was familiar with frankincense and knew it was harvested from trees in southern Arabia. He reported that the gum was dangerous to harvest because of venomous snakes that lived in the trees. He goes on to describe the method used by the Arabs to get around this problem, that being the burning of the gum of the styrax tree whose smoke would drive the snakes away. The resin is also mentioned by Theophrastus and by Pliny the Elder in his Naturalis Historia.

Southern Arabia was a major exporter of frankincense in antiquity, with some of it being traded as far as China. The Chinese writer and customs inspector Zhao Rugua wrote on the origin of frankincense, and of its being traded to China:

"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 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."

Quality

Frankincense comes in many types, and its quality is based on color, purity, aroma, age, and shape. Silver and Hojari are generally considered the highest grades of frankincense.

Currently, there are two dissertations which may enable the identification of a few Olibanum species according to their specific secondary metabolism products.

Production

Estimates of the current annual world production of frankincense vary, but generally are around several thousands tonnes. More than 82% of the product comes from Somalia, with some frankincense also gathered in adjacent Southern Arabia and Ethiopia, Sudan, and other central African countries.

In Somalia, frankincense is harvested in three ecological zones: the northern Cal Madow mountain range, a westerly escarpment that runs parallel to the coast and grows frankinscence-bearing species; Cal Miskeed, a middle segment of the frankincense-growing escarpment; and Cal Bari or eastern escarpment, which lies at the eastern fringe of the frankinscence escarpment. Frankincense is also produced in the Karkaar mountains. Frankincense is also produced in the mountains lying at the northwest of Erigavo and Eil-afweyn zones.

Uses

Frankincense is used in perfumery and aromatherapy. It is also an ingredient that is sometimes used in skincare. The essential oil is obtained by steam distillation of the dry resin. Some of the smells of the frankincense smoke are products of pyrolysis.

Frankincense is used in many Christian churches including the Eastern Orthodox, Oriental Orthodox and Catholic churches. According to the gospel of Matthew 2:11, gold, frankincense, and myrrh were among the gifts to Jesus by the biblical magi "from out of the East." Christian and Islamic Abrahamic faiths have all used frankincense mixed with oils to anoint newborn infants, initiates and members entering into new phases of their spiritual lives.

Conversely, the spread of Christianity depressed the market for frankincense during the 4th century AD. Desertification made the caravan routes across the Rub' al Khali or "Empty Quarter" of the Arabian Peninsula more difficult. Additionally, increased raiding by the Parthians in the Near East caused the frankincense trade to dry up after A.D. 300.

Traditional medicine

Frankincense resin is edible and is used in traditional medicines in Africa and Asia for digestion and healthy skin. For internal consumption, it is recommended that frankincense be translucent, with no black or brown impurities. It is often light yellow with a (very) slight greenish tint. It is often chewed like gum, but it is stickier.

In Ayurvedic medicine frankincense (Boswellia serrata), commonly referred to in India as "dhoop," has been used for hundreds of years for treating arthritis, healing wounds, strengthening the female hormone system and purifying the air. The use of frankincense in Ayurveda is called "dhoopan". In Somali, Ethiopian, Arabian, and Indian cultures, it is suggested that burning frankincense daily in the house brings good health.

Frankincense oil can also be used for relief from stings such as scorpion stings.

Frankincense essential oil

The essential oil of frankincense is produced by steam distillation of the tree resin. The oil's chemical components are 75% monoterpenes, sesquiterpenes, monoterpenoles, sesquiterpenols and ketones. It has a good balsamic sweet fragrance, while the Indian frankincense oil has a very fresh smell. Contrary to what some commercial entities claim, steam or hydro distilled frankincense oils do not contain boswellic acids (triterpenoids), although may be present in trace quantities in the solvent extracted products. The chemistry of the essential oil is mainly monoterpenes and sesquiterpenes, with small amounts of diterpenoid components being the upper limit in terms of molecular weight.

Perfume

Olibanum is characterised by a balsamic-spicy, slightly lemon, fragrance of incense, with a conifer-like undertone. It is used in the perfume, cosmetic and pharmaceutical industries.

Medical research

For therapy trials in ulcerative colitis, asthma and rheumatoid arthritis there are only isolated reports and pilot studies from which there is not yet sufficient evidence of safety and efficacy. Similarly, the long-term effects and side effects of taking frankincense has not yet been scientifically investigated. Nonetheless, several preliminary studies have been published.

A 2008 study reported that frankincense smoke was a psychoactive drug that relieves depression and anxiety in mice. The researchers found that the chemical compound incensole acetate was responsible for the effects.

In a different study, an enriched extract of "Indian Frankincense" (usually Boswellia serrata) was used in a randomized, double-blinded, placebo-controlled study of patients with osteoarthritis. Patients receiving the extract showed significant improvement in their arthritis in as little as seven days. The compound caused no major adverse effects and, according to the study authors, is safe for human consumption and long-term use.

In a study published in 2009, it was reported that "Frankincense oil appears to distinguish cancerous from normal bladder cells and suppress cancer cell viability."

A 2012 study in healthy volunteers determined that exposure to 11-keto-β-boswellic acid (KBA), a lead boswellic acid in the novel solubilized frankincense extract Boswelan, is increased when taken with food. However, simulations based on a two-compartment pharmacokinetic model with single first-order absorption phase proposed that the observed food interaction loses its relevance for the simulated repeated-dose scenario.

In a 2012 study, researchers found that the "behavioral effect [of insensole actetate] was concomitant to reduced serum corticosterone levels, dose-dependent down-regulation of corticotropin releasing factor and up-regulation of brain derived neurotrophic factor transcripts IV and VI expression in the hippocampus. These data suggest that IA modulates the hypothalamic–pituitary–adrenal (HPA) axis and influences hippocampal gene expression, leading to beneficial behavioral effects supporting its potential as a novel treatment of depressive-like disorders."

In study published in 2014, researchers found "the effects of frankincense and sandalwood essential oils on J82 cells and UROtsa cells involved different mechanisms leading to cancer cell death. While frankincense essential oil elicited selective cancer cell death via NRF-2-mediated oxidative stress, sandalwood essential oil induced non-selective cell death via DNA damage and cell cycle arrest."

Chemical composition

These are some of the chemical compounds present in frankincense:

See also for example the following references which give a comprehensive overview on the chemical compounds present in different frankincense species:.