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- Author or Editor: F. Guo x
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A rapid method has been used for simultaneous identification of both hydrophilic and lipophilic compounds from Radix Salviae Miltiorrhizae (RSM, the root of Salvia miltiorrhiza BGE.) by ultra-performance liquid chromatography/quadrupole time-offlight mass spectrometry (UPLC/Q-TOF-MS). A total of 58 compounds extracted by methanol were detected and tentatively identified within 20 min, including hydrophilic phenolics, lipophilic diterpenoids, a verbascose, and several organic acids. These compounds were separated on an Acquity UPLC BEH C18 column and identified based on tandem mass spectrometry (MS/MS) fragmentation patterns under the positive and negative ion modes, respectively. Among them, micranthin B and 9-oxo-10E,12Zoctadecadienoic acid were reported in RSM for the first time. Their fragmentation patterns in electrospray ionization (ESI)—MS/MS spectra were first investigated by matching their accurate molecular masses. This contribution presented one of the first reports on the analysis of hydrophilic phenolics and lipophilic diterpenoids from Radix Salviae Miltiorrhizae using UPLC/Q-TOF-MS. The results demonstrated that UPLC/Q-TOF-MS method could be applied to rapidly and expediently describe and provide comprehensive chemical information for simultaneous analysis of two different polar components in RSM.
Phyllostachys edulis (PES), the most important bamboo species in China, is widely distributed in East Asia. Flavonoids, which are important bioactive natural compounds, often have similar structures, making their structural elucidation difficult. The aim of this study was to represent valuable, reliable mass spectral data for the identification of flavonoids in plant leaves. Ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (UPLC–Q-TOF-MS/MS) method was established for characterization and identification of the major flavonoids in PES leaf extract. A total of 13 flavonoids were simultaneously characterized, and their proposed characteristic product ions and fragmentation pathways were investigated. Thirteen compounds were separated on an Agilent Zorbax RRHD SB-C18 column (150 mm × 2.1 mm, 1.8 μm). On the basis of comparing with the 4 reference standards and the literature data, the other 9 flavonoids were identified by tandem mass spectrometry (MS/MS). Eight compounds (compounds 1, 4, 5, 8, 9, 10, 11, and 12) were found in PES leaves for the first time. An efficient UPLC–QTOF-MS/MS method was successfully applied for the structural identification of flavonoids in PES leaves. These results have practical applications for the rapid identification and structural characterization of these compounds in crude bioactive extracts or mixtures.
Background and aims
This study aims to examine the mediating effects of insomnia on the associations between problematic Internet use, including Internet addiction (IA) and online social networking addiction (OSNA), and depression among adolescents.
Methods
A total of 1,015 secondary school students from Guangzhou in China participated in a cross-sectional survey. Levels of depression, insomnia, IA, and OSNA were assessed using the Center for Epidemiological Studies-Depression Scale, Pittsburgh Sleep Quality Index, Young’s Diagnostic Questionnaire, and Online Social Networking Addiction Scale, respectively. Logistic regression models were fit to test the associations between IA, OSNA, insomnia, and depression. The mediation effects of insomnia were tested using Baron and Kenny’s strategy.
Results
The prevalence of depression at moderate level or above (CES-D ≥ 21), insomnia, IA, and OSNA were 23.5%, 37.2%, 8.1%, and 25.5%, respectively. IA and OSNA were significantly associated with depression (IA: AOR = 2.79, 95% CI: 1.71, 4.55; OSNA: AOR = 3.27, 95% CI: 2.33, 4.59) and insomnia (IA: AOR = 2.83, 95% CI: 1.72, 4.65; OSNA: AOR = 2.19, 95% CI: 1.61, 2.96), after adjusting for significant background factors. Furthermore, insomnia partially mediated 60.6% of the effect of IA on depression (Sobel Z = 3.562, p < .002) and 44.8% of the effect of OSNA on depression (Sobel Z = 3.919, p < .001), respectively.
Discussion
The high prevalence of IA and OSNA may be associated with increased risk of developing depression among adolescents, both through direct and indirect effects (via insomnia). Findings from this study indicated that it may be effective to develop and implement interventions that jointly consider the problematic Internet use, insomnia, and depression.
