Deciphering the chemical origin of the semen-like floral scents in three angiosperm plants. (January 2018)

• Record Type: Journal Article
• Authors: Zhang, Xiaoping; Chingin, Konstantin; Zhong, Dacai; Luo, Liping; Frankevich, Vladimir; Chen, Huanwen
• Is Part Of: Phytochemistry. Volume 145(2018)
• Page Start: 137
• Page End: 145
• Publication Date: 2018-01
• Subjects: Semiochemicals -- Semen-like odor -- 1-Pyrroline -- Photinia serrulata -- Castanopsis sclerophylla -- Stemona japonica -- Direct ambient corona discharge ionization mass spectrometry -- Sapromyophily -- Pollination; Botanical chemistry -- Periodicals; Biochemistry -- Periodicals; Botany -- Periodicals; Chimie végétale -- Périodiques; 572.2
• DOI: 10.1016/j.phytochem.2017.11.001
• Languages: English
• ISSNs: 0031-9422

Abstract

Abstract: 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. Graphical abstract: Image 1 Highlights: The semen-like flower odor shares similar molecular profile across different families. 1-Pyrroline is the major molecular component responsible for the semen-like odor. The semen-like flower odor is released to attract dipterans. Several volatiles were identified in the studied flowers for the first time. Ambient corona ionization offers sensitive detection of volatile amines from flowers.