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51.
茵陈挥发油GC-MS指纹图谱分析 总被引:9,自引:0,他引:9
建立了茵陈挥发油GC-MS指纹图谱,将正交投影算法用于不同样本中共有峰的提取,提高了共有峰的识别能力,降低了由于保留时间的漂移、质谱检索匹配度不高以及色谱峰重叠而引起的共有峰识别的难度.采用共有峰率、变异率及相似度等几个指标对4个不同产地的茵陈挥发油成分进行了评价,从共性、差异和整体性等多个方面全面表征茵陈挥发油的化学模式特征.结果表明,不同产地的茵陈挥发油成分大致相同,该指纹图谱可用于茵陈中挥发油成分的质量控制. 相似文献
52.
反相高效液相色谱法测定不同产地白花蛇舌草中的对香豆酸 总被引:4,自引:0,他引:4
用反相高效液相色谱法对不同产地的白花蛇舌草中对香豆酸的含量进行了测定。色谱柱采用DiamonsilTM ODS柱(4.6 mm i.d.×250 mm, 5 μm),流动相为乙腈-20 mmol/L NH4Ac(pH 4.0)(体积比为15∶85),流速1.0 mL/min,柱温为室温,检测波长为308 nm。在上述条件下测得对香豆酸的质量浓度为4.04~202 mg/L时与色谱峰面积之间线性关系良好(r=0.9996),高中低浓度条件下的平均回收率为97.4%~102.2%。该方法快速简便,精密度高,重现性和准确度良好,可以作为白花蛇舌草质量控制的一个有效方法。 相似文献
53.
Two new oplopane sesquiterpenes, gmelinin A(1) and gmelinin B(2), were isolated from Artemisia gmelinii Web. ex Stechm. Their structures were established by spectroscopic techniques(mainly 1D and2 D NMR) and application of the modified Mosher method. 相似文献
54.
Zhi‐Yong Xie Ting‐Ting Lin Mei‐Cun Yao Jin‐Zhi Wan Sheng Yin 《Helvetica chimica acta》2013,96(6):1182-1187
Two new guaiane sesquiterpenoids, (1β,5β)‐1‐hydroxyguaia‐4(15),11(13)‐dieno‐12,5‐lactone ( 1 ) and 1,5‐epoxy‐4‐hydroxyguai‐11(13)‐en‐12‐oic acid ( 2 ), together with five known compounds, rupestonic acid ( 3 ), strobilactone A ( 4 ), antiquorin ( 5 ), isosclerone ( 6 ), and 5‐hydroxy‐2′,3′,4′,7,8‐pentamethoxyflavone ( 7 ), were isolated from a 95% EtOH extract of Artemisia rupestris. Compounds 1 and 2 are rare examples of guaiane sesquiterpenoids, incorporating a 12,5‐lactone group or featuring a 1,5‐epoxy ring, respectively. The structures of 1 and 2 were identified by various spectroscopic methods. Compounds 1, 4 , and 5 exhibited moderate cytotoxic activities against the human lung cancer 95‐D cell line with IC50 values of 11.3, 19.8, and 34.5 μM , respectively. 相似文献
55.
56.
Marchand E Atemnkeng MA Vanermen S Plaizier-Vercammen J 《Biomedical chromatography : BMC》2008,22(5):454-459
Owing to the development of parasite resistance to standard antimalarial treatments like chloroquine and sulfadoxine-pyrimethamine, the demand for Artemisia annua, a key ingredient for new and highly effective antimalarial drugs, is huge. Therefore selective and precise methods to determine the content of artemisinin in dry plant material and in raw impure extracts are needed. In this work a method is described for the clear separation and extraction of artemisinin from other plant components in the Artemisia annua L. plant by thin-layer chromatography (TLC). To obtain optimal extraction and recovery efficiency, several parameters were evaluated, including choice of extraction solvent, TLC plate type and sensitivity between UV and visible light. Method validation was performed on both the dry plant material and non-purified plant extracts. Toluene presented the highest extraction efficiency compared with petroleum ether, hexane and methanol. Reversed-phase plates showed more concentrated spots than normal-phase plates, while the sensitivity of the analysis in UV was comparable to that in visible light but less precise. The impure plant extracts were analyzed by both TLC and HPLC-UV at 215 nm and both methods met the requirements for linearity, selectivity, precision and accuracy. Hence, the proposed TLC method can easily be used for both qualitative and quantitative control of the raw plant extract in areas where advanced methods are scarce. 相似文献
57.
从蒿属植物白莲蒿(Atemisia sacrorumLedeb.)地上部分分得4个肉桂酸类化合物,经理化常数测定,光谱(红外光谱、核磁共振光谱、质谱)分析,分别鉴定为:1,4-二咖啡酰奎宁酸(1,4-dicaffcoylquinic acidⅠ),水杨酸(salicylic acidⅡ),黎芦酸(veratric acidⅢ),琥珀酸(succinic acidⅣ),其中,1,4-二咖啡酰奎宁酸经药理活性试验证明有良好的抗质子过氧化和保肝作用。 相似文献
58.
Halina Ekiert Ewa Knut Joanna
witkowska Pawe Klin Agnieszka Rzepiela Micha Tomczyk Agnieszka Szopa 《Molecules (Basel, Switzerland)》2021,26(9)
Artemisia abrotanum L. (southern wormwood) is a plant species with an important position in the history of European and Asian medicine. It is a species famous as a medicinal plant in Central Asia, Asia Minor, and in South-East and Central Europe. The raw materials obtained from this species are Abrotani herba and Abrotani folium. In the traditional European medicine, they have been used successfully most of all in liver and biliary tract diseases, in parasitic diseases in children and as antipyretic medication. In the official European medicine, this plant species is recommended by the French Pharmacopoeia for use in homeopathy. In many European countries, it is used traditionally in allopathy. The latest studies on the biological activity of extracts from the aboveground parts of the plant and/or the leaves, and/or the essential oil have provided evidence of other possible applications related to their antibacterial, antifungal, antioxidant, anticancer, and antiallergic properties. The latest studies have also focused on the repellent activity of the essential oil of this species and the possibility to use it in the prevention of diseases in which insects are the vectors. The main substances obtained from the plant that are responsible for this activity are: the essential oil, coumarins, phenolic acids, and flavonoids. Some of the latest investigations emphasize the large differences in the composition of the essential oil, determined by the geographical (climatic) origin of the plant. A. abrotanum is recommended by the European Cosmetic Ingredients Database (CosIng) as a source of valuable cosmetic ingredients. Additionally, the leaves of this species possess a well-established position in the food industry. This plant species is also the object of biotechnological studies. 相似文献
59.
Artemisia jordanica (AJ) is one of the folkloric medicinal plants and grows in the arid condition used by Palestinian Bedouins in the Al-Naqab desert for the treatment of diabetes and gastrointestinal infections. The current investigation aimed, for the first time, to characterize the (AJ) essential oil (EO) components and evaluate EO’s antioxidant, anti-obesity, antidiabetic, antimicrobial, anti-inflammatory, and cytotoxic activities. The gas chromatography-mass spectrometer (GC-MS) technique was utilized to characterize the chemical ingredients of (AJ) EO, while validated biochemical approaches were utilized to evaluate the antioxidant, anti-obesity and antidiabetic. The microbicidal efficacy of (AJ) EO was measured utilizing the broth microdilution assay. Besides, the cytotoxic activity was estimated utilizing the (MTS) procedure. Finally, the anti-inflammatory activity was measured utilizing a COX inhibitory screening test kit. The analytical investigation revealed the presence of 19 molecules in the (AJ) EO. Oxygenated terpenoids, including bornyl acetate (63.40%) and endo-borneol (17.75%) presented as major components of the (AJ) EO. The EO exhibited potent antioxidant activity compared with Trolox, while it showed a weak anti-lipase effect compared with orlistat. In addition, the tested EO displayed a potent α-amylase suppressing effect compared with the positive control acarbose. Notably, the (AJ) EO exhibited strong α-glucosidase inhibitory potential compared with the positive control acarbose. The EO had has a cytotoxic effect against all the screened tumor cells. In fact, (AJ) EO showed potent antimicrobial properties. Besides, the EO inhibited the enzymes COX-1 and COX-2, compared with the anti-inflammatory drug ketoprofen. The (AJ) EO has strong antioxidant, antibacterial, antifungal, anti-α-amylase, anti-α-glucosidase, and COX inhibitory effects which could be a favorite candidate for the treatment of various neurodegenerative diseases caused by harmful free radicals, microbial resistance, diabetes, and inflammations. Further in-depth investigations are urgently crucial to explore the importance of such medicinal plants in pharmaceutical production. 相似文献
60.
Anjali D. Ruikar Ravindra B. Jadhav Usha D. Phalgune Supada R. Rojatkar Vedavati G. Puranik Nirmala R. Deshpande 《Helvetica chimica acta》2011,94(1):73-77
Two new eudesmanolides, pallensin ( 1 ) and 4‐epipallensin ( 2 ), along with a known eudesmanolide, santonin, and a known flavone, 4‐epivalgarin, have been isolated from the aerial part of A. pallens. Their structures were established by detailed spectral studies (1D and 2D) and by comparison of their spectroscopic data with those of known compounds. 相似文献