基于顶空及SERS分子识别的薤与韭的挥发物研究

摘要

顶空及表面增强拉曼散射（SERS）分子识别技术应用于新鲜薤、韭的挥发性物质研究，直接测得了以纳米银溶胶作为基底的薤、韭的挥发物的 SERS 光谱，并与液态烯丙基甲基硫醚（allyl methyl sulfide）、1-丙硫醇（1-propanethiol）、二烯丙基二硫（diallyl disulfide）及三者中两两混合后的挥发物的SERS 谱进行比对。结果显示薤、韭的挥发物的SERS光谱重现性非常好；薤的挥发性物的SERS谱与液态烯丙基甲基硫醚和1-丙硫醇混合后的挥发物的SERS谱基本一致，薤的挥发物的SERS 谱中既有烯丙基甲基硫醚挥发物的SERS谱的特征峰：626和674 cm－1，又有1-丙硫醇挥发物的 SERS 谱的特征峰：702，893，1024，1085，1215，1320 cm－1；韭的挥发物的SERS谱与液态烯丙基甲基硫醚和二烯丙基二硫混合后的挥发物的SERS谱基本一致，韭的挥发物的SERS谱中既有烯丙基甲基硫醚挥发物的SERS谱的特征峰：674 cm－1，又有二烯丙基二硫挥发物的SERS谱的特征峰，407，577，716，1189，1291，1401 cm－1。说明薤的挥发物中含有烯丙基甲基硫醚和1-丙硫醇成分；韭的挥发物中含有烯丙基甲基硫醚和二烯丙基二硫成分；薤和韭的挥发物虽有所差异，但都含有烯丙基甲基硫醚成分。证明顶空技术结合SERS分子识别技术可用于直接对薤和韭的挥发物研究。该技术在常温下进行，能保证得到的挥发物即为植物所含物种的原始成分，通过与标样对比，可确定植物中挥发物的组成。%The headspace and the molecular recognition of surface enhanced Raman scattering (SERS)were used to research vol-atiles of rakkyo and Chinese chive.Their volatiles SERS spectra were obtained using nano-silver colloid as the substrate$Then, volatiles SERS spectra of rakkyo and Chinese Chive were compared respectively with the volatiles SERS spectra of liquid allyl methyl sulfide,1-propanethiol,diallyl disulfide and all possible pairings of the three compounds.The results showed that the re-peatability of volatiles SERS spectra of rakkyo and Chinese Chive were all good.The volatiles SERS spectrum of rakkyo was ba-sically consistent with the volatiles SERS spectrum of the mixture of liquid allyl methyl sulfide and 1-propanethiol.The volatiles SERS spectrum of rakkyo included both characteristic peaks at 626 and 674 cm-1 in volatiles SERS spectrum of allyl methyl sul-fide and characteristic peaks at 702,893,1 024,1 085,1 215 and 1 320 cm-1 in volatiles SERS spectrum of 1-Propanethiol.The volatiles SERS spectrum of Chinese chive was basically consistent with the volatiles SERS spectrum of the mixture of liquid allyl methyl sulfide and diallyl disulfide.The volatiles SERS spectrum of Chinese chive included both characteristic peak at 674 cm-1 in volatiles SERS spectrum of allyl methyl sulfide and characteristic peaks at 407,577,716,1 189,1 291 and 1 401 cm-1 in vol-atiles SERS spectrum of diallyl disulfide.These illustrated that volatiles of rakkyo contained allyl methyl sulfide and 1-Propane-thiol and volatiles of Chinese chive contained allyl methyl sulfide and diallyl disulfide.The volatiles of rakkyo and Chinese chive were different,but they all contained allyl methyl sulfide.All of the above have revealed that the headspace combined with mo-lecular recognition of SERS can be directly used to study volatiles of rakkyo and Chinese chive.The technology under room tem-perature,can guarantee the volatiles obtained were the primitive constituents in plant volatiles.By comparison with the standard sample,the constituents in plant volatiles can be determined.