A new method based on high performance liquid chromatography-electrospray ionization time of flight-mass spectrometry (HPLC-ESI-TOF/MS) was developed for the rapid identification of active compounds in Styela clava and the development of its specific chromatograms. Samples were extracted by ultrasonic-assisted extraction, and the extraction conditions were optimized. The developed HPLC-ESI-TOF/MS method was used to identify the components in Styela clava extract, and a specific chromatogram based on HPLC analysis was established. Ten compounds in Styela clava extract have been primary identified by HPLC-ESI-TOF/MS on-line detection combined with literature review. The result of similarity evaluation for specific chromatograms indicated that the quality of different Styela clava samples was not entirely consistent. This method has the advantages of simple operation, rapid measurement and it is a powerful tool for identification of active components in Styela clava and its quality control.

To establish a rapid method for analysis of gingerol-related compounds in fresh ginger by using high performance liquid chromatography coupled with electron spray ionization-quadrupole-time of flight mass/mass spectrometry (HPLC-ESI-Q-TOF-MS/ MS). The gingerol-related compounds in fresh ginger was separated by an Inertsil ODS-SP column (4.6 mm x 250 mm, 5 microm) using a binary eluent under gradient conditions. The analytes were detected by ESI-Q-TOF-MS/MS in positive ion mode to obtain MS and MS/MS spectra and to extract molecular weights. From the MS data, the accurate molecular weights of gingerol-related compounds were obtained, and from the MS/MS data, the (+) ESI-Q-TOF-MS/MS fragments were obtained. 25 gingerol-related compounds were identified from fresh ginger by attentive studying on the mass spectra of compounds and comparing with reference data reported in the literature, respectively. This method was certified to be accurate and reliable and can be used for the rapid analysis of gingerol-related compounds in fresh ginger.
Catechols ; analysis ; Chromatography, High Pressure Liquid ; methods ; Fatty Alcohols ; analysis ; Ginger ; chemistry ; Spectrometry, Mass, Electrospray Ionization ; methods ; Tandem Mass Spectrometry ; methods

ObjectiveTo compare the effects of different drying methods on volatile components of Pseudostellariae Radix. MethodThe samples were dried by different methods， including air drying， sun drying， hot air drying （40， 60， 80 ℃） and vacuum freeze drying. Gas chromatography-ion mobility spectrometry （GC-IMS） was used to compare the changes of volatile components in the samples after different treatments. The samples were incubated at 80 ℃ and 500 r·min^-1 for 15 min， the injection temperature was 85 ℃， the injection volume was 200 μL， the flow rate of carrier gas was from 2 mL to 150 mL during 20 min， and the temperature of IMS detector was 60 ℃. SE-54 capillary column （0.32 mm×30 m， 0.25 μm） was used， the column temperature was 60 ℃， and the analysis time was 35 min. The differential spectra of volatile components were constructed and analyzed by principal component analysis （PCA）. ResultA total of 37 volatile components were identified from dried Pseudostellariae Radix. The number of compounds in descending order was ketones， aldehydes and alcohols. There were some differences in the volatile components in samples dried by different methods. And the volatile components in samples with sun drying， air drying and hot air drying at 40 ℃ were similar， compared with other drying methods， vacuum freeze drying and hot air drying at 80 ℃ had great effects on the volatile components of Pseudostellariae Radix， and the compounds in the samples with vacuum freeze drying were the least. ConclusionIn this study， GC-IMS for the detection and analysis of volatile components in Pseudostellariae Radix is established， which has the characteristics of high efficiency， nondestructive inspection and simple sample processing. This method can be used for the distinction of Pseudostellariae Radix dried by different methods. And hot air drying at 40 ℃ can effectively retain the volatile components of Pseudostellariae Radix， and achieve similar flavor to samples with sun drying and air drying.