沉香多级提取物的化学成分及释香行为

Chemical Constituents and Aroma Release Behavior of Multi-Stage Extracts of Agarwood

[目的]沉香提取物是其主要应用方式之一。针对不同应用领域对沉香成分需求存在显著差异的问题,在提取过程中对沉香主要成分进行粗犷分离,明确不同提取物的释香行为,为实现沉香在特定领域的定向、高效利用提供参考。[方法]以传统沉香和奇楠沉香为研究对象,通过水蒸气-溶剂多级提取,获得精油、浸膏、醇沉等沉香多级提取物;利用气相色谱质谱联用(GC-MS)和高效液相色谱(HPLC)技术,分析不同品种沉香多级提取物的化学成分差异;采用顶空-气相色谱联用(HS-GC-MS)技术,分析传统沉香和奇楠沉香多级提取物在40~160℃的香气释放规律。[结果]水蒸气-溶剂多级提取可实现传统沉香和奇楠沉香中倍半萜、色酮类成分的粗犷分离;水中蒸馏和隔水蒸馏对精油成分影响较小,均主要含有倍半萜和芳香族小分子物质,相对峰面积≥99%;蒸馏后再进行溶剂提取,获得的浸膏主要含有色酮类成分,相对峰面积≥90%;醇沉可实现对传统沉香浸膏中杂质的有效分离。2种沉香多级提取物的主要化学成分和释香成分存在显著差异:传统沉香、奇楠沉香精油中,分别主要含有榄香醇、α-檀香醇,40℃时主要释香物质分别为匙叶桉油烯醇、(1R,3aR,5aR,9aS)-1,4,4,7-Tetramethyl-1,2,3,3a,4,5a,8,9-octahydrocyclopenta[c]benzofuran;传统沉香浸膏中色酮种类更为丰富,160℃后色酮裂解形成大量小分子挥发性物质,出峰数量和强度明显高于奇楠沉香。[结论]通过多级提取方式,可获得富含倍半萜类化合物的沉香精油以及富含色酮类成分的沉香浸膏、杂质较高的醇沉。精油在低温时具有较好的香气释放能力,适合开发香水、日化等常温释香产品;浸膏适用于高温释香,可开发熏香、燃香等产品;奇楠沉香浸膏中主要成分为2-(2-苯乙基)色酮、2-[2-(4-甲氧基苯基)乙基]色酮,可用于该色酮的单体分离;醇沉中沉香有效物质明显降低,可开发低值化产品。

[Objective]Agarwood extract is one of the main applications.According to the problem that there are significant differences in the demand for agarwood ingredients in different application fields,this work focused on the main components of agarwood by crude separation during the extraction process,and clarified the incense release behavior of different extracts,aiming to provide references for the directional and efficient utilization of agarwood in specific fields.[Method]Taking the traditional agarwood(CX)and new variety Qinan agarwood(QN)as the research objects,three extracts of essential oil,extractum,and alcohol precipitation were obtained by the steam-solvent multi-stage extraction.The main chemical components of CX and QN’s multi-stage extracts were studied by gas chromatography-mass spectrometry(GC-MS)combined with high performance liquid chromatography(HPLC).Headspace-gas chromatography(HS-GC-MS)was used to analyze the aroma release rules of CX and QN’s multi-stage extracts at 40−160℃.[Result]The crude separation of CX and QN sesquiterpenoids and chromones was achieved by the steam and solvent multi-stage extraction.There is little effect on the components of the essential oil obtained by distillation in water and out of water.The relative peak areas of sesquiterpenoids and other small molecules were≥99%.After distillation,solvent extraction was carried out and the extractum mainly contained chromone,and the relative peak area was≥90%.The alcohol precipitation method was suitable for CX extract extractum to effectively separate impurities.There were significant differences in the main components and aroma release components between CX and QN.The elemenol andα-santalol were the main component from CX and QN essential oil,respectively.Both of CX and QN had good aroma release ability at low temperatures.The main aroma releasing substances of CX and QN were eucalyptol and(1R,3aR,5aR,9aS)-1,4,4,7-tetramethyl-1,2,3,3a,4,5a,8,9-Octahydrocyclopenta[c]benzofuran at 40℃,respectively.The types of chromones in CX extractum were relatively richer.The chromone could be dissociated to form small molecule volatile substances at 160℃.Both of the number and intensity of CX’s pyrolysis products were significantly higher than those of QN.[Conclusion]By multi-stage extraction method,agarwood essential oil rich in sesquiterpenoids,agarwood extract rich in chromones and alcohol precipitation with high impurities were obtained.Essential oil has a good aroma release ability at low temperature,which is suitable for the development of perfumes,daily chemicals and other room temperature fragrance release products.Extractum is suitable for high temperature incense release,and can be developed incense,burning incense and other products.QN extract mainly contains 2-(2-phenylethyl)chromone and 2-[2-(4-methoxyphenyl)ethyl]chromone,which can be used for monomer separation of the chromone.The active substance of agarwood in alcohol deposition is obviously reduced,and low value products can be developed.