Abstract:

The volatile oil of Flos Magnoliae was extracted by simultaneous distillation extraction (SDE) method,
hydrodistillation (HD) method and static headspace (SH) method, respectively. Quantitative analyses of volatile oils were
carried out by retention index using gas chromatography-mass spectrometry (GC-MS) combined with database searching.
To compare the volatile oils extracted with the HD and SDE methods, we used Prussian blue method and the Neocuproine
method to examine their antioxidant activities, used 1,1-diphenyl-2-picrylhydrazyl (DPPH) to determine their free radical
scavenging abilities, and used the filter paper method and the 96-well plate method to measure their antibacterial activities.
The results showed that a total of 66 chemical compounds were identified in the volatile oils extracted with the above three
methods, 17 compounds of which were common to the three oils, showing significant differences in the relative amount
of each of them. A total of 47, 43 and 26 volatile compounds were identified in the oils extracted with HD, SDE and SH,
respectively. The composition of volatile compounds extracted with HD and SDE was similar, while SH extracted the
smallest number of compounds. The Flos Magnoliae volatile oils extracted by HD and SDE showed an obvious antioxidant
activity, as well as the ability to inhibit Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salmonella
typhimurium, especially Gram-negative bacteria. The antioxidant activity and antibacterial activity showed the potential
usage of Flos Magnoliae volatile oils as natural food preservatives in the pharmaceutical and food industries.

Key words: Flos Magnoliae (Xinyi), volatiles, gas chromatography-mass spectrometry (GC-MS), static headspace, simultaneous distillation extraction, hydrodistillation, antioxidant, antimicrobial