Studies And Analisis Of Volatile Components From Plants Via Ultrasound/microwave Assisted Extraction

Ultrasonic/microwave assisted extraction(UMAE),combination of microwave and ultrasonic wave technologies,with the assistances of ultrasonic cavitation and high-energy microwave,simultaneously energy out of ultrasonic vibration and microwave toward samples and thus has advantages of simple operation,short extracting time,energy effectiveness in the extraction process.In the sections that follow,four kinds of sample pretreatment methods have been compared and volatile substances extracted from four common plants have been analyzed.The main content includes:1.In the first chapter,a review is given of principle,development andapplication of UMAE as well as of particular relevant researches on volatile oil and aromatic water.2.In the second chapter,the extracting techniques involving microwave-assisted extraction(MAE),ultrasonic microwave-assisted extraction(UMAE),traditional steam distillation(SD)and ultrasonic assisted steam distillation(UASD)of volatile oil from Amomum kravanh Pierre ex Gagnep were optimized and compared.Different parts of Amomum kravanh Pierre ex Gagnep were extracted using MAE coupled with gas chromatography/mass spectrometry.The extraction rates of volatile oil were 1.28%?1.38%?1.03%and 1.19%,respectively and the total number of 57,53,55,45 compounds were identified corresponding to MASD,UMASD,SD,UASD.40 conpounds were identified by these four extraction methods.The extraction rates of volatile oil were 1.24%?1.13%and 1.31%from Amomum kravanh Pierre ex Gagnep?shell and seed,respectively.They mainly consist of Eucalyptol,a-Terpineol,P-Pinene,Linalool,?-cis-Terpineol,a-Pinene,et al.The results show that there is no obvious difference among extraction components by these four methods.MAE is alternative to SD in terms of extraction rates and extraction time.The results suggest that MAE is an efficient,rapid,simple and green preparation technique.3.The third chapter optimize and compare MAE,UMAE,SD and UASD extraction of the volatile oil from Illicium verum Hook.f and the MAE extraction of volatile oil from different parts of Illicium verum Hook.f coupled to GC/MS,with extraction rate of volatile oil 4.0%?6.1%?4.1%and 4.1%while the total number of 63,57,67,66 compounds identified for MASD,UMASD,SD,UASD,respectively.56 conpounds were identified by these four extraction methods.The extraction rates of volatile oil 4.0%?5.2%and 2.1%were obtained from fruit,shell and seed out of Illicium verum Hook.f.,respectively.The main components include Trans-Anethol,Estragole,Anise aldehyde,Cis-Anethol,Linalool,et al.The comparison of these four methods suggests that UMAE can accelerate the extracting process and improve volatile oil extraction.The results imply that UMAE and MAE will be more efficient volatile oil extracting technique in the future.4,In the fourth chapter,volatile oil from Zingiber of ficinale Rosc were extracted by MAE,UMAE,SD and UASD before GC/MS analysis.The extraction rates of volatile oil were 0.87‰,0.88‰,0.91‰ and 0.94‰,respectively.The results show that the total numbers of identified compounds were 54,46,45,42 using MASD,UMASD,SD,UASD,respectively and 41 compounds identified by these four extraction methods mainly involving Zingiberene,Citral,?-Sesquiphellandrene,P-Citral,a-Curcumene,et al.After secondary magnetic stirring coupled to dispersion-micro-liquid extraction of aromatic water from Zingiber of ficinale Rosc.,3,7-dimethyl-2,6-octadiene-aldehyde,P-Citral,Borneol,Trans-Geraniol,a-Terpineol are found.The results indicate that the four methods are green techniques due to water as extract solvent;These four methods have not much obvious differences with volatile oils extraction rate and extraction components considerations.MASD and UMASD are alternative to SD in comparison with extraction time.This study suggests that UMASD is an efficient,rapid,simple and green preparation technique.5.The fifth chapter was to compare UMAE-HeadSpace Solid-Phase Micro Extraction(HS-SPME)with SD in extracting volatile components from Atractlodesm acrocephala Koidz.Optimal conditions for the experiment were to use PDMS/DVB fiber with the temperature of 103?,the ultrasonic time was 4 min and the ultrasonic power should be 600 W,as for microwave,both microwave processing and extracting time were 8 min and microwave power should be 600 W.The number of identified compounds were 52 and 30 corresponding to UMAE-HS-SPME and SD.The highest amount of extraction for both UMAE-HS-SPME and SD was Atractylon with percentage of relative content 23.56%,61.41%,respectively.16 compounds were identified by the two extraction methods,accounting for 89.43%of the SD extracting content.It is demonstrated that UMAE-HS-SPME in comparison with SD is more suitable and more attractive extract method for Atractlodesm acrocephala Koidz.-like volatile components which is rapid in extraction time,effective in energy,simple in operation and complete in extracting components.