Profiling of compounds in hydrosol extract of Aquilaria (Agarwood) species using gas chromatography-mass spectrometry (GCMS)

Most research involving agarwood mainly focused on extracting the agarwood oil from the infiltrated resin, the most sought non-timber forest product from Aquilariaspecies with high demand and prices. This led to other parts of this valuable plant species being considered as waste. This includes the agarwood hydrosol (by-product of water distillation). Hydrosol has been reported to retain certain aromatics of its primary essential oil. Therefore, the aim of the present study is to identify the composition of the agarwood hydrosol extracts from Aquilariaspecies by using gas chromatography-mass spectrometry (GCMS). Six agarwood hydrosol samples from different batches of production were used in this study and designated as S1 until S6. The hydrosol extracts were prepared in three steps; isolation of dissolved essential oil, filtration of the hydrosol extract and finally the evaporation of solvent (hexane). The resulting extracts were subjected to GCMS analysis. A total of 46, 48, 40, 53, 58 and 62 compounds were detected in hydrosol extract samples of S1, S2, S3, S4, S5 and S6, respectively. Accordingly, the oxygenated and phenolic compounds were found to be present in all hydrosol extract samples. The detected phenolic compounds include phenol, 2,5-bis (1,1-dimethylethyl)-,.phenol, 2,4-bis (1,1-dimethylethyl)- and 9-octadecenoic acid (Z)-, methyl ester. These compounds are believed to possess various potential biological activities including antioxidant activities. Sample S1 and S2 consist of sesquiterpene compounds such as (-)-aristolene, naphthalene, decahydro-4a-methyl-1- methylene-7- (1-methylethylidene)-,(4aR-trans), azulene,1,2,3,3a,4,5,6,7-octahydro-1,4-dimethyl-7- (1-methylethenyl)-,[1R-(1.alpha.,3a.beta.,4.alpha.,7.beta.)]- and alloaromadendrene where the later had the highest number of oxygenated and antioxidant compounds. In conclusion, results from this study suggests that agarwood hydrosol possesses myriad of compounds that warrant further investigation based on their potential medicinal benefits. This in turn could help realize the waste to wealth paradigm as well as promote the material as sustainable source for development of halal therapeutics