Zhang Xiaoping, Chingin Konstantin, Zhong Dacai, Luo Liping, Frankevich Vladimir, Chen Huanwen
Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, PR China.
Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation, East China University of Technology, Nanchang, 330013, PR China.
Phytochemistry. 2018 Jan;145:137-145. doi: 10.1016/j.phytochem.2017.11.001. Epub 2017 Nov 8.
The chemical origin and biological role of distinct semen-like odor occasionally found in some flowers are very curious but remain scarcely studied. Here, we used direct ambient corona discharge ionization mass spectrometry (MS) to study the volatile chemical composition behind the semen-like odor emitted by the fresh flowers of Photinia serrulata, Castanopsis sclerophylla and Stemona japonica without any chemical pretreatment. Chemical identification was performed using high-resolution MS analysis in combination with tandem MS analysis and whenever possible was confirmed by the analysis of standard reference compounds. A total of 19 compounds, mostly belonging to nitrogenous volatiles, were identified in P. serrulata, C. sclerophylla, and S. japonica flowers, 1-pyrroline, 1-piperideine, 2-pyrrolidone, and phenethylamine being common in all the three studied species. Several lines of evidence indicate that the major component responsible for the semen-like odor is most likely 1-pyrroline. 1-Pyrroline is most probably formed via the oxidative deamination of putrescine, as indicated by the observation of signal from 4-amino-butanal intermediate. Flower visitation observations suggest that the released volatiles serve to attract dipterans, including Syrphidae, Calliphoridae, and Muscidae. On the analytical side, the comparison of our results to earlier studies also indicate that compared to the traditional GC-MS approach the direct corona discharge ionization mass spectrometry provides more sensitive detection of VOCs with high proton affinity, in particular volatile amines, and therefore can be used to complement traditional GC-MS approach for the highest chemical coverage of VOC analysis.
某些花朵中偶尔出现的类似精液气味的化学起源和生物学作用非常令人好奇，但仍几乎未被研究。在这里，我们使用直接常压电晕放电电离质谱（MS），在不进行任何化学预处理的情况下，研究石楠、苦槠和百部鲜花所散发的类似精液气味背后的挥发性化学成分。通过高分辨率MS分析结合串联MS分析进行化学鉴定，并尽可能通过标准参考化合物分析进行确认。在石楠、苦槠和百部的花朵中总共鉴定出19种化合物，大多数属于含氮挥发物，1-吡咯啉、1-哌啶、2-吡咯烷酮和苯乙胺在所有三个研究物种中都很常见。几条证据表明，造成类似精液气味的主要成分很可能是1-吡咯啉。如4-氨基丁醛中间体信号的观察所示，1-吡咯啉很可能是通过腐胺的氧化脱氨形成的。花朵访察观察表明，释放的挥发物有助于吸引双翅目昆虫，包括食蚜蝇科、丽蝇科和蝇科。在分析方面，将我们的结果与早期研究进行比较也表明，与传统的气相色谱-质谱联用（GC-MS）方法相比，直接电晕放电电离质谱对具有高质子亲和力的挥发性有机化合物（VOCs），特别是挥发性胺类，提供了更灵敏的检测，因此可用于补充传统的GC-MS方法，以实现VOC分析的最高化学覆盖范围。
