利用SFC和双监测PDA和FTIR纯化薄荷油中的香芹酮

精油中的萜烯很容易被氧化，会导致食物风味下降。去除萜烯通常用于香料工业中，以产生更高质量的油。天然留兰香油含有l-柠檬烯，与d-柠檬烯截然不同，其香气不会让人想起柑橘，而是淡淡、干净的萜烯碳氢化合物香气。通常，萜烯是使用真空蒸馏除去的。然而，在这个过程中很难实时监测分馏过程。我们使用SFC与PDA检测器和FTIR光谱仪作为双重监测系统，以便在洗脱和分级过程中实时选择性监测目标化合物香芹酮。PDA提供了关于分离的广泛信息，但不能区分柠檬烯和香芹酮。Application Note 2/4Application NotePurification of Carvone in Spearmint Oil Purification of Carvone in Spearmint Oil using SFC with PDA and FTIR Dual-Monitoring Terpenes i n essential oils are easily oxidized and can cause a d e crease in the flavor in foods.Removal of T erpenes is commonly practiced in perfume in d ustry to yield higher quality o i ls.Natural spearmint oilcontains I-limonene that is quite unlike d-limonene， the aroma is not rem i niscent of ci t rus but of a light， c l ean T erpene hydrocarbon f ragra n ce. Conventionally， Terpenes are removed using vacuum distillation. However ，it is difficult to monitor the fractionation process in real -ti me dur i ng this process. We used SFC with a PDA detector and an FTIR spectrometer as a dual monitoring system to enable selec ti ve m onitor i ng of the target compound Carvone in real t ime during elution and fractionation. The PDA provides broad information on the separation， but cannot differentiate between l i monene an d Carvone. Keyword： Terpenes， esse n tial oil purification， Spearmint Oil，Limonene， Carvone， CO2， SFC， FTIR， Enrichment HPLC-FTIR Table 1. Co n s ti t u e nt s of Spea rmin t O il Component Percent Content a-Pinene 0.40 B-Pinene 0.51 Limonene 20.80 B-Borbonene 0.80 Octanol 0.61 Mentol 1.03 Dihydrocarbeol 2.71 Dihydrocarvyl 1.92 Carvone 59.70 Cis-， Trans-dihydrocarvone 3.65 Mentone 1.50 Total 93.63 Figure 1. St r u c t u r es of C arvone and Li m o n ene. d-ca r vone i s presen t i n caraway oil w h ile l -c a rvone is present in s p ear m int oil.T h ey are e a sily d i f f erent iat e d b y t h e n ose.d -l i m o n e n e is p r ese nt in c itrus o ils wh il e I-limo n ene i s pr e se n t in s p e a r m int oil， pin e o i l， e tc .It is d es i r a b l e to r e move I-lim o nene from s p earmint o il. Figure 2. UV and I R Spect r a of L im o nene and Ca r v o n e Standards . Figure 2， Limonene and Carvone have very simil a r UV spect r a ， but show differences i n the IR. Co-elu t ion in the chromatogram detected using UV as shown in f igure 3 and 4 i llustrates the i nability of us i ng UV to t r igger f ract i on collection. Figure 5 shows I R chromatograms at t wo different wave number ranges and the fractions collected using those chromatograms . A Carvone standard and Spearmint oil were separated using HPLC and fractions 1and 2 were compared to confirm the separation and purity as seen in Fi g ure 6. SFC Conditions Figure 3. PDA C on t o ur Pl o t of S p earm in t Oil . The PDA c o u l d n ot d i f f e rent i a t e lim o nen e f r o m c ar v on e d u e t o apparent c o -e lu ti o n .T h er ef or e f r a ct i o n t im in g c o u l d n o t b e se t b a s e d o n t h e PDA. Figure 4. SFC Chrom a t o grams of Sp e a rm i nt Oil by PDA D e t ec t i on. Figure 5. I R Chromatog r a m o f Spearmin t Oil u sed f or F r act i onation. Figure 6. HPLC Chromatograms HPLC Co n d it i on s： C o lum n ： Crest p ak C18S， M o bile P h a se： CH3C N /H2O 60/40Flow r a te： 1.0mL/min ， C o l um n Tem p er a ture： 40℃. Conclusions The carvone content in the original spearmint oi l (62.7%) was success f ully enriched to 89.1%. During the fractionation process the limonene peak was clearly detected using FT I R and was easily removed as fraction 1. HPLC was used to analyze the pur i ty of the two fractions and conf i r m ed the removal l imonene from the spearmint oil. A p plicat i o n L i br a r y ： htt p ：//www.j as co i n c .c o m /ap p l i c a ti o n s