Malaysian Journal of Chemistry, 2017, Vol. 19(1), 33–58
Sesquiterpenes and Chromones of Agarwood: A Review
Daoud Tajeldeinn Ahmaed1* and Ajaykumar D. Kulkarni2
1Faculty of pharmacy, Pharmaceutical Chemistry Department, Omdurman Islamic university,Khartoum, Sudan
2Department of Applied Sciences, MIT Academy of Engineering (An Autonomous Institute Affi liated to Savitribai Phule Pune University), Dehu Phata, Alandi (D), Pune, 412105, India
Received: January 2017; Accepted: April 2017
This study is to characterize and profile the chemical constituents of Aquilaria species, mainly Aqularia malaccensis, Aqularia sinensis, and Aqularia crassna. This precious wood has long been used traditionally in religious ceremonies in the form of incense and oil. There are variations among the chemical group that has been identified in this species, mostly sesquiterpenoids, chromones and volatile aromatic compounds. Studies on the chemistry of agarwood smoke are discussed. Emphasis is given to structural and analytical aspects through this study. The agarwood grading system totally depended on its physical characteristics; there was no scientific approach based on the chemical profile which was used to classify the different grades of agarwood. A different type of analytical technique was used to isolate single pure compounds from chip wood of agarwood, and solvent refluxing was the most popular among them. The polar solvent was found to be used to obtain the polar compounds and chromium, while most of the sesquiterpene was obtained from the non-polar solvent. For extraction of agarwood, hydrodistillation was the most common technique to extract the oil and followed by supercritical fluid extraction, while steam distillation and Soxhlet distillation was rarely used. Different analytical instrumentation were used for the investigation of the chemical profile of agarwood such as GC-FID, GC-MS, GC-MS-OLF which were the most common research tools. The chemical profile of the wood from the different species and countries all looked different except the Vietnamese Aquilaria sinensis, and A. agallocha which seemed to have a very closed chemical profile. There were remarkable similarities in the chemical profile of A. agallocha India (wood ), A. agallocha Vietnam (wood), and A. sinensis Vietnam (wood) with the minor absence of some compounds from A. agallocha India (wood). From the literature, we could say that the 6-methoxy-2-[2-(4 -methoxypheny1)-ethyl]chromone and2-(2 (4methoxyphenyl)ethyl)chromone was the most dominate chromones found in all species.
Key words: Aquilaria malaccensis; Aquilaria sinensis; Aquilaria crassna; GC-FID; GC-MS; SPME; sesquiterpene
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