气质联用鉴别降香黄檀与越南香枝的研究

为了研究降香黄檀与越南香枝木材中的化学成分,采用顶空/气质联用法测定了降香黄檀与越南香枝可挥发性成分与脂溶性成分,通过对指纹图谱的对比分析,得出一种可以准确区分两种材质的鉴别方法。结果表明:在可挥发性成分测定中,顶空进样器平衡温度是影响可挥发性成分检出种类及量的主要因素之一,可挥发性成分检出种类及量随平衡温度增高而增加; 两材种可挥发性成分较多,均达30种以上,且种类相似,虽含量有差别但不足以构成其特征性差异,无法将两材种加以区分。在脂溶性成分测定中,乙酸乙酯是提取两材种脂溶性成分的最佳试剂,石油醚提取效果较差,甲醇提取液对检测系统污染程度较高; 两材种脂溶性成分丰富、相同成分众多,且差异性成分也多。两材种均含大量的橙花叔醇、反式-橙花叔醇和6,7-环氧-蛇麻烯等3种脂溶性成分,三者之和均可达脂溶性成分总量的40%以上。越南香枝中有5种含量较高的脂溶性成分即3,3',4,4'-四甲氧基二苯乙烯、松属素、3-(2,4-二甲氧基苯基)-7-甲氧基苯并二氢吡喃、3,4-二氢-7-甲氧基-3-(2,3,4-三甲氧基苯基)-2H-1-苯并吡喃、N-2-(3,4-二甲氧基苯基)乙基]-3-甲氧基-苯甲酰胺,这5种脂溶性成分在越南香枝中含量之和占总脂溶性成分的20%～40%,而在降香黄檀中不足1%,由此可将两材种进行有效鉴别和区分。分析认为,降香黄檀与越南香枝两材种的化学成分差异显著,其中可挥发性成分差异不明显,无法以此准确区分材种,而脂溶性成分种类及含量差异显著,可准确区分两材种。

The identification of Dalbergia odorifera and D.tonkinensi by gas chromatography mass spectrometry

For identifing Dalbergia odorifera and D. tonkinensi accurately, the volatile components and fat-soluble ingredients of D. odorifera and D. tonkinensi are tested with gGC-MS. In detecting volatile components, equilibrium temperature of headspace sampler was one of the main factors that the volatile substance species and quantity increased with increasing of the equilibrium temperature. These two wood species share more than 30 kinds of volatile components with great similarity but little difference in content, which was not characteristic for identification.In detecting fat-soluble ingredients ethyl acetate was the best extraction reagent. Both wood species occupied many similar and different fat-soluble ingredients. Similar ingredients included large amounts of 3,7,11-trimethyl-1,6,10-dodecatrien-3-ol,(6Z)3,7,11-trimethyl-1,6,10-dodecatrien-3-ol and 6,7-epoxide humulene(6Z), which accounted for more than 40% of the total fat-soluble ingredients.D. tonkinensi occupies 5 ingredients with higher content which amount up to 20%-40% of total fat-soluble substance, namely, 3,3',4,4'-tetra-methoxystilbene, 5,7-dihydroxyflavanone, 3-(2,4-dimethoxyphenyl)-7-methoxychroman, 3,4-dihydro-7-methoxy-3-(2,3,4-trimethoxyphenyl)-2H-1-benzopyran and N-2-(3,4-dimethoxyphenyl)ethyl]-3-methoxy-benzamide. However, these substance add up to less than 1% in D. odorifera, making these two species differentiable. In a word, volatile components resemble but fat-soluble ingredients differed distinctly, which was the basis for identification of D. odorifera and D.tonkinensi with GC-MS.