Study On Extraction And Biological Activity Of Agarwood Essential Oil

In this study,the quality of the agarwood essential oil extracted by different methods was identified by using GC-MC and other methods,and it was analyzed and clarified that the microwave-assisted extraction method is a green and efficient preferred method for the extraction of agarwood essential oil.The method of microwave-assisted extraction of agarwood essential oil is optimized for process,and the relevant process parameters in the method are clarified.Finally,the antioxidant performance of agarwood essential oil is scientifically compared,which provides a certain theoretical basis and technical guidance for the industrial production and quality control of agarwood essential oil And provided certain support for the comprehensive development and utilization of agarwood essential oil.The main findings are as follows:1.Using agarwood of ant incense in Xishuangbanna as raw material,prepare agarwood essential oil by water bath reflux extraction method,Soxhlet extraction method,ultrasonic assisted extraction method and microwave assisted extraction method,using gas chromatography-mass spectrometry(gas chromatography-mass)spectrometry(GC-MS)analyzes the essential oil composition,and compares the effects of four extraction methods on the preparation of agarwood essential oil based on the essential oil yield,ingredient type and composition,and the content of characteristic components.The results showed that the composition of essential oils prepared by the four extraction methods were similar,mainly including sesquiterpenes,aromatics,chromones and fatty acids,but the contents were significantly different;the extraction rate of the agarwood essential oil prepared by microwave-assisted extraction The highest and the most substance types are 1.32% and 70 types,respectively,and the types and contents of sesquiterpenoids and aromatic substances reflecting the quality of agarwood essential oil are higher than those of the other three methods,respectively 19,20 and 22.29%,12.36%,and the content of fatty acids is the lowest,which is 24.30%;Ultrasound-assisted extraction method has the highest content of chromones in essential oil,38.62%,followed by microwave-assisted extraction method,which is 36.52%;microwave only The six characteristic substances in the essential oil obtained by the method were all detected.Among them,the content of agarol spiritol,guaiacyl alcohol,atractylol,(+)-yumonene,?-eucalyptus alcohol was the highest,respectively 1.53%,1.73%,0.19%,1.47% and 1.69%.In summary,the microwave-assisted extraction method is the best extraction method of agarwood essential oil among the four methods,and has the characteristics of high extraction rate and good quality of essential oil.2.Combined with response surface analysis,the best technology for extracting agarwood essential oil by microwave-assisted extraction method is: material-liquid ratio 8.20: 1,microwave power 335 W,extraction temperature 38.47 ?,extraction time 5.97 min,and the maximum extraction rate is 1.479%.The regression equation between the extraction rate(Y)of agarwood essential oil(Y)and the ratio of material to liquid(A),microwave power(B),extraction temperature(C)and extraction time(D)is: Y= 0.011375 A + 0.00487333 B + 0.23582 C + 0.83617 D + 0.110015 AC + 0.024750 AD + 0.000137BC+ 0.0014CD-0.011615A~2-0.075833D~2-6.41400.The material composition of Aquilaria essential oil before and after process optimization is basically similar,which are mainly composed of sesquiterpenes,aromatics,chromones,fatty acids,etc.There is a small difference in the content of each common substance.The content of sesquiterpenes,aromatics,and chromones in the optimized agarwood essential oil was higher than that in the prior optimization,22.19%,7.30%,and 31.15%,respectively.The quality is more excellent;the optimized agarwood essential oil has a fatty acid content lower than the agarwood essential oil before optimization,which is 10.07%,indicating that the optimized agarwood essential oil is superior in stability quality.The quality of the agarwood essential oil obtained after the microwave-assisted extraction process optimization is improved.3.Through the determination of the scavenging ability of agarwood essential oil to DPPH free radicals,hydroxyl radicals and superoxide anion free radicals,agarwood essential oil shows a certain antioxidant capacity in each system.As the concentration of agarwood essential oil increases,the antioxidant The ability is gradually enhanced,with obvious relevance.The agar dilution method was used to determine the antibacterial and bactericidal effects of agarwood essential oil on Escherichia coli,Salmonella,Staphylococcus aureus,and Aspergillus niger,indicating that agarwood essential oil has broad-spectrum antibacterial properties,which provides a theoretical basis for the comprehensive development and utilization of agarwood essential oil.