Abstract:

Objective: The research compared the differences in secretion distribution, the types and relative contents of main chemical components between Qi-Nan agarwood and ordinary agarwood, and analyzed the antibacterial effect of the two kinds of agarwood on cigarette gas to provide a significant scientific basis for the quality assessment and rational utilization of Qi-Nan agarwood. Method: Taking 10 batches of Qi-Nan agarwood and 9 batches of ordinary agarwood as the research objects, the distribution of secretions was investigated using the microsection method, the chemical composition of the secretions was examined using gas chromatography-mass spectrometry(GC-MS) and the smoke components of incense sticks produced by Qi-Nan agarwood and ordinary agarwood were analyzed using headspace solid-phase microextraction coupled with gas chrom·atography-mass spectrometry(HS-SPME-GC-MS). Additional, the air disinfection effect test was used to test the inhibitory effects of smoke on natural bacteria, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Result: Both Qi-Nan agarwood and or ordinary agarwood generally accumulate their secretions in included phlocm and ray parenchyma cells. However, Qi-Nan agarwood has a higher organization ratio of these two organizations than ordinary agarwood. Qi-Nan agarwood has a substantially greater secretion content than regular agarwood. Also, the chemical composition of Qi-Nan agarwood and ordinary agarwood differs significantly. While Qi-Nan agarwood has a higher relative content of chromones than ordinary agarwood, the relative content of sesquiterpenoids in ordinary agarwood is lower. The majority of the chromones in Qi-Nan agarwood are 2-(2-phenylethyl)chromone and 2-[2-(4-methoxy)phenethyl]chromone, with a combined relative content of 77.3% compared to 1.5% in ordinary agarwood. Lastly, aromatic chemicals, sesquiterpenoids, and chromone derivatives made up the smoke produced by burning the Qi-Nan and ord agarwood incense sticks. The smoke composition comprises more aromatic compounds than the chemical composition of secretions, which is mostly made up of aromatic compounds in secretions, products of secretions cracked, and products of wood cracked. Moreover, Sagarwoodphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa are all strongly inhibited by the smoke of two types of burnt agarwood incense sticks, with a kill rate of more than 99%. Yet, the Qi-Nan agarwood incense sticks' antibacterial impact on natural bacteria in the air is superior than that of ordinary agarwood. Conclusion: The secretion characteristics of Qi-Nan agarwood and ordinary agarwood are significantly different and they are produced by different types of Aquilaria sinensis. Qi-Nan agarwood has a high secretion content and is rich in 2-(2-phenylethyl)chromone and 2-[2-(4-methoxy)phenethyl]chromone, and when it is burned to make incense, it has a strong antibacterial effect that is slightly superior to that of ordinary agarwood.

Key words: Qi-Nan agarwood, ordinary agarwood, secretion characteristics, antibacterial activity