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31.
Suan‐Zao‐Ren granule is widely used to treat insomnia in China. However, because of the complexity and diversity of the chemical compositions in traditional Chinese medicine formula, the comprehensive analysis of constituents in vitro and in vivo is rather difficult. In our study, an ultra high performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry and the PeakView® software, which uses multiple data processing approaches including product ion filter, neutral loss filter, and mass defect filter, method was developed to characterize the ingredients and rat serum metabolites in Suan‐Zao‐Ren granule. A total of 101 constituents were detected in vitro. Under the same analysis conditions, 68 constituents were characterized in rat serum, including 35 prototype components and 33 metabolites. The metabolic pathways of main components were also illustrated. Among them, the metabolic pathways of timosaponin AI were firstly revealed. The bioactive compounds mainly underwent the phase I metabolic pathways including hydroxylation, oxidation, hydrolysis, and phase II metabolic pathways including sulfate conjugation, glucuronide conjugation, cysteine conjugation, acetycysteine conjugation, and glutathione conjugation. In conclusion, our results showed that this analysis approach was extremely useful for the in‐depth pharmacological research of Suan‐Zao‐Ren granule and provided a chemical basis for its rational.  相似文献   
32.
毛蕊杜鹃挥发油化学成分研究   总被引:1,自引:0,他引:1  
毛蕊杜鹃(Rhododendron tubulosum Ching ex wang wei-yei)系杜鹃花科杜鹃花属植物,分布于四川、西藏、甘肃和青海,其中青海分布最广,藏民常作为单方草药用于治疗肺炎和老年慢性气管炎,具有镇咳、祛痰作用,本文用自制的同时水汽蒸馏-溶剂萃取装置,从采自青海玉树州的毛蕊杜鹃鲜叶和嫩枝提取挥发油,用毛细管气相色谱-质谱和Kovats指数双重定性法对  相似文献   
33.
The branches and leaves of Pyrus pashia are used to cure abdominal pain and diarrhoea in Chinese folk medicine. A new phenilic compound, 4-O-β-d-glucopyranosylbenzyl-benzoate ester (1), along with 21 known ones (2–22) were isolated from the branches and leaves of this plant. Compounds 2 and 3 displayed remarkable antioxidant activities against 1,1-diphenyl-2-picrylhydrazyl radical (IC50 = 13.26 ± 0.04 μM, 13.28 ± 0.11 μM, respectively), which were at the same grade as positive control rutin. The caffeoyl group in compounds 2 and 3 was supposed to play an important role in the antioxidant activities.  相似文献   
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35.
The aim of this research was to determine the chemical composition, antioxidant and antibacterial properties of the essential oils from Cynanchum chinense and Ligustrum compactum and isolation of antioxidant and antibacterial constituents from the essential oils. Thirty-eight components were identified in essential oils. Based on bioactivity-guided fractionation, guaiacol, linalool and 2-phenylethanol were isolated and identified as active constituents. Both L. compactum flower oil and 2-phenylethanol showed high antibacterial performance, with inhibition zone from 22.8 ± 0.8 to 11.9 ± 2.0 mm at highest concentration, and minimum inhibitory concentration values ranging from 0.25% to 1%. In both DPPH and ABTS assay, the active constituent guaiacol (IC50 = 4.15 ± 0.72 and 9.12 ± 0.98 μg mL? 1, respectively) exhibited high antioxidant activity, and the oils showed moderate antioxidant activity. These results indicate potential efficacy of active constituents and essential oils of L. compactum and C. chinense to control food-borne pathogenic and spoilage bacteria.  相似文献   
36.
This article reports the lipophilic chemical composition of different processed products (Changii Radix, Changii Radix Alba) and parts (root bark, leaf and fruit) of Changium smyrnioides Wolff.. The lipophilic constituents were extracted with petroleum ether in Soxhlet apparatus, subsequently identified and determined by gas chromatography–mass spectroscopy (GC–MS). Yield of lipophilic constituents from Changii Radix (3.65%) was about three times more than Changii Radix Alba's (1.07%), which indicated processing by boiling in water had an impact on the content of lipophilic constituents. Moreover, the major compounds in different processed products and parts were found to be fatty acids and sesquiterpenes. The results are a contribution for the lipophilic chemical composition and can serve as a reference for product development of Changium smyrnioides Wolff..  相似文献   
37.
Ardisiae Japonicae Herba is a well‐known traditional Chinese medicine for the treatment of bronchitis conjunctivitis, pneumonia, and trauma. In this work, a high‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry method was first established for the separation and structural identification of the chemical constituents in Ardisiae Japonicae Herba. A total of 15 compounds including coumarins, flavonoid glycosides, and catechins were identified or tentatively characterized based on their chromatographic behaviors and mass spectral fragmentation and by comparisons with the reference standards. Furthermore, a simple high‐performance liquid chromatography with diode array detection method was developed for the simultaneous determination of five major constituents. Results obtained from method validation, including linearity, precision, repeatability, stability, and recovery, showed that the established method was reliable and accurate. Bergenin and quercitrin were found to be the most abundant constituents and could be served as chemical markers for quality control of Ardisiae Japonicae Herba.  相似文献   
38.
Oxidative stress has been reported as a cause of many diseases like Parkinson′s, Alzheimer′s, cardiovascular disease, and diabetes. Oxidative stress can also lead to cancer formation by promoting tumor development and progression. Antioxidants derived from Lamiaceae plants play an important role in natural medicine, pharmacology, cosmetology, and aromatherapy. Herein, we examine the antioxidative capacity of essential oils from seven aromatic Lamiaceae plants against the synthetic radicals DPPH and ABTS. Among the essential oils analyzed, the most robust scavenging capacities were found in mixtures of volatile compounds from thyme and savory. The scavenging activity of tested EOs against the ABTS radical was clearly higher than activity towards DPPH. Analysis of essential oils with weaker antioxidant activity has shown that volatile compounds from marjoram, sage, and hyssop were more active than EOs from lavender and mint. It can be suggested that the potent antioxidant capacity of thyme (Thymus vulgaris) and savory (Satyreja hortensis) are related to a high level of phenolic constituents, such as thymol and carvacrol. On the other hand, the elevated antioxidative power of marjoram, sage, and hyssop essential oils may also be due to their terpinene, o-cymene, terpinolene, and terpinen-4-ol constituents. Although non-phenolic components are less active than thymol or carvacrol, they may affect antioxidant capacity synergistically.  相似文献   
39.
Aronia berry (black chokeberry) is a shrub native to North America, of which the fresh fruits are used in the food industry to produce different types of dietary products. The fruits of Aronia melanocarpa (Aronia berries) have been found to show multiple bioactivities potentially beneficial to human health, including antidiabetic, anti-infective, antineoplastic, antiobesity, and antioxidant activities, as well as heart-, liver-, and neuroprotective effects. Thus far, phenolic compounds, such as anthocyanins, cyanidins, phenolic acids, proanthocyanidins, triterpenoids, and their analogues have been identified as the major active components of Aronia berries. These natural products possess potent antioxidant activity, which contributes to the majority of the other bioactivities observed for Aronia berries. The chemical components and the potential pharmaceutical or health-promoting effects of Aronia berries have been summarized previously. The present review article focuses on the molecular targets of extracts of Aronia berries and the examples of promising lead compounds isolated from these berries, including cyanidin-3-O-galactoside, chlorogenic acid, quercetin, and ursolic acid. In addition, presented herein are clinical trial investigations for Aronia berries and their major components, including cancer clinical trials for chlorogenic acid and COVID-19 trial studies for quercetin. Additionally, the possible development of Aronia berries and their secondary metabolites as potential therapeutic agents is discussed. It is hoped that this contribution will help stimulate future investigations on Aronia berries for the continual improvement of human health.  相似文献   
40.
Matricaria recutita L., German chamomile, is one of the most widely used medicinal plants, whose efficacy has been proven in numerous studies. However, its roots have attracted only little interest so far, since mainly above-ground plant parts are used for medicinal purposes. To broaden the knowledge of chamomile roots, a profound phytochemical characterization was performed along with a bioactivity screening of corresponding root extracts. While volatile constituents such as chamomillol and polyynes were detected using GC-MS, HPLC-MSn analyses revealed the occurrence of four coumarin glycosides, more than ten phenolic acid esters and five glyceroglycolipids. Furthermore, the antioxidant activity of the extracts was evaluated. Polar extracts revealed IC50 values ranging from 13 to 57 µg/mL in the DPPH radical scavenging assay, which is in the same range as reported for chamomile flower extracts. In addition, superoxide radical scavenging potential and mild antibacterial effects against S. aureus und B. subtilis were demonstrated. Moreover, to assess interspecies variation in chamomile roots, extracts of M. recutita were compared to those of M. discoidea DC. Interestingly, the latter revealed stronger antioxidant activity. The presented results aim at the valorization of chamomile roots, previously discarded as by-product of chamomile flower production, as a sustainable source of bioactive phytochemicals.  相似文献   
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