Boswellia

Boswellia serrata j-Camphorene (Compound 4) and p-Camphorene (Compound 5) and Cembrenol (Serratol)... 

Olibanum (frankincense) is one of a group known as the oleogum resins (mono-, sesqui-, di-, and triterpenes and mucous substances) that exude from incisions in the bark of the Boswellia trees (fam Burseraceae), the most common species of which are B. carterii (Sudan, Somalia, and Ethiopia) and B. serrata (India), whereas B. frereana (Oman, Somalia) and B. sacra (Arabia) belong to the rare resins on the market. 

A perceptible marker of the olibanum fragrances coming from Somalia, Sudan, or Ethiopia is the aliphatic octyl acetate marked by a distinct acrid smell. Boswellia carterii contains up to 50% of the aliphatic octyl acetate, demonstrated by the strong stinging smell of the fume, whereas Boswellia serrata (its common name in India is salai guggul) contains none or only small amounts of it and, consequentiy, does not have such a harsh smell. 

Another striking difference relates to the diterpenes (Figure 16.3) B. carterii reveals strong peaks that have been assigned to verticilla-4 (20),7,ll-triene (compound 1), incensole acetate (compound 2), and incensole (compound 3) and, on the other hand, Boswellia serrata shows peaks of m- and / -camphorene (compoimd 4 and compound 5) as well of cembrenol (= serratol) (compound 6). 

Boswellia carterii Verticilla-4(20),7,11-Triene (Compound 1) and the Other Cembrenes... 

To summarize, generally, the diterpenes of both investigated Boswellia species are suitable for marker substances. Figure 16.9 clearly demonstrates that for TLC... 

Basar, S., Koch, A., and Konig, W.A., A verticillane-type diterpene from Boswellia carterii essential oil. Flavour Fragrances J., 16, 315, 2001. 

Basar, S., Phytochemical Investigations on Boswellia Species, Dissertation Hamburg, 2005. 

Frankincense Trees of genus Boswellia Watt and Sellar (1996) Martinetz et al. (1988) Groom (1981)... 

Burseraceae Commiphora (myrrh) Boswellia (olibanum or frankincense) Canarium (elemi) a and (3 amyrin, euphanes, oleananes... 

Frankincense, also known as olibanum, is obtained from trees belonging to the genus Boswellia (Burseraceae family). It is one of the best-known ancient plant resins. The ancient Egyptians were the first to use it as incense in embalming practices and in the preparation of medicines, cosmetics and perfumes, and today it is still used therapeutically. It contains pentacyclic triterpenoids belonging to oleanane, ursane or lupane type molecules and in particular of a- and p-boswellic acids, and their O-acetates [104 111], 11 -Oxo-p-boswellic acid and its acetyl derivative, identified in several Boswellia species, are also diagnostic for frankincense [112]. 

G. Culioli, C. Mathe, P. Archier, C. Vieillescazes, A lupane triterpene from frankincense (Boswellia sp., Burseraceae), Phytochemistry, 62, 537 541 (2003). 

R.S. Pardhy, S.C. Bhattacharyya, P Boswellic acid, acetyl P boswellic acid, acetyl 11 keto P boswellic acid and 11 keto P boswellic acid, four pentacyclic triterpene acids from the resin of Boswellia serrata Roxb, Indian Journal of Chemistry, 16B, 176 178 (1978). 

Frankincense, also called olibanum, is a natural oleo gum resin that exudes from incisions in the bark of Boswellia trees [46, 47]. Diterpenes like incensole or isoincensole and their oxide or acetate derivatives (see Figure 10.3) are characteristic biomarkers of olibanum [48]. Although diterpenoid hydrocarbons possessing the cembrane skeleton have been isolated from a variety of terrestrial and marine organisms, their occurrence and particularly that of cembrenes A and C (see Figure 10.3) is supplementary proof of the presence of olibanum in a sample. Optimisation of the SPME conditions was done with the aim of trapping these low volatile diterpenes. 

The first observation is the similarity between the chemical compositions of both the Boswellia carteri and Boswellia sacra. For these three olibanum samples, a-pinene (2), (3-myrcene (8) and limonene (14) are the predominant monoterpenes. p-Caryophyllene (73) is the major sesquiterpene besides a-copaene (65), a-humulene (also called a-caryophyllene) (78) and caryophyllene oxide (95). The characteristic olibanum compounds isoincensole and isoincensole acetate (128) together with cembrene A (120) are the main diterpenes. 

Boswellia serrata olibanum has a chemical composition close to that of both the B. carteri and of B. sacra, but contains compounds that are absent in those from other Boswellia and could be used as markers methylchavicol (38), p-anisaldehyde (47), methyleugenol (70), isocaryophyllene (82), sesquiterpene 91, elemicin (92) and an unidentified diterpene (124) eluting between cembrene C (123) and verticilla-4(20),7,ll-triene (125). It is devoid of (5-caryophyllene (73), a-humulene (78), caryophyllene oxide (95) and bornyl acetate (50). 

The chemical composition of B. papyrifera olibanum is markedly different from that of other Boswellia, with small amounts of monoterpenes and sesquiterpenes, large amounts of w-octanol (18) and -octy I acetate (40), with the latter being the major compound, and the presence of particular diterpenes [incensole (127), incen-sole acetate (129), incensole oxide (130) and incensole oxide acetate (131)] and the absence of both isoincensole and isoincensole acetate (128). Linear carboxylic acids from hexanoic acid (10) to lauric acid (93) were also identified in B. papyrifera olibanum exclusively. 

Eight olibanum samples of unknown botanical origin have been analysed [26]. The chemical compositions are summarized in Table 10.3 for three of them. Both the olibanum coming from Somalia and that from a market in Ta izz (Yemen) have been attributed to Boswellia carteri or sacra on the basis of the occurrence of the characteristic diterpenes isoincensole and isoincensole acetate (128) together with diterpene 126. The absence of methylchavicol (38), oxygenated sesquiterpene 91 and diterpene 124 and the presence in relatively large amount of (3-caryophyllene (73), ot-humulene (78) and caryophyllene oxide (95) excluded the hypothesis of a B. serrata sample. 

A number of important resins are composed of triterpenoids, including the dammar resins which derive from a sub-family of the family Dipterocarpaceae. Dammar resins are fluid, balsamic oleoresins highly suited for caulking and waterproofing. Frankincense (olibanum) is known as a gum-resin collected from various Boswellia spp. and contains amyrin epimers and triterpenoid acids. The gum component is polysaccharide in origin and is water soluble. The Anacardiaceae family contains the genus Pistacia (Mills and White, 1977 21 Mills and White, 1989). 

Flepatic mixed function oxidase inhibition. Oleoresin, administered to rats at a dose of 250 mg%, was active " " ". Hypocholesterolemic activity. A hot mixture of Nigella sativa, Commiphora myrrha, Ferula assafoetida, Aloe vera, and Boswellia serrata, administered by gastric intubation to rats at a dose of 0.5 g/kg for 7 days, was active vs streptozotocin-induced hyperglycemia " " ". 

Olibanum oil and olibanum resinoid are obtained from frankincense, which is a gum resin collected from the bark of the tree Boswellia carterii Birdw. or B. frereana Birdw. (Burseraceae) growing in Arabia and Somalia. The resinoid is produced by solvent extraction, and steam distillation gives the oil, which is a pale yellow, slightly viscous liquid with a balsamic odor and a faint lemon note. 

Various qualities are commercially available. Their compositions may vary considerably because they are prepared from the resins of different Boswellia species. Main constituents of the oil are monoterpene hydrocarbons [284a, 658-661a]. 

Acetyl-11-keto-P-boswellic acid (AKBA) 196 Boswellia serrata resin 5LOX. HLA [93,153-155]... 

Another gum resin is frankincense, obtained by cutting notches in the stem of Boswellia carterii, which grows in northeastern Africa and in Arabia. This resin is used in incense. Asafoetida is also a gum resin. See also Gums and Mucilages. 

Negative tests were obtained for the remainder of the samples Boswellia serrala, Bursera aptera, Bursera sp. aff. aptera, B. arho-... 

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