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Novel uniform-sized magnetic molecularly imprinted polymers (MMIPs) were synthe- sized for selective recognition of active antitumor ingredients of kaempferol (KMF) and protoapi- genone (PA) in Macrothelypteris torresiana (M. torresiana) by surface molecular imprinting tech- nique in this study. Super paramagnetic core-sheU nanoparticles (γ-MPS-SiO2@Fe3O4) were used as seeds, KMF as template molecule, acrylamide (AM) as functional monomer, and N, N'-methylene bisacrylamide (BisAM) as cross-linker. The prepared MMIPs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectrum fiT/R), transmission electron microscopy (TEM) and thermo-gravimetric analysis (TGA), respectively. The recognition capacity of MMIPs was 2.436 times of non-imprinted polymers. The adsorption results based on kinetics and isotherm analysis were in accordance with the pseudo-second-order model (R2=0.9980) and the Langmuir adsorption model (R2=0.9944). The value of E (6.742 kJ/mol) calculated from the Dubinin-Radushkevich isotherm model suggested that the physical adsorption via hydrogen-bonding might be predominant. The Scatchard plot showed a single line (R2=0.9172) and demonstrated the homogeneous recognition sites on MMIPs for KMF. The magnetic solid phase extraction (MSPE) based on MMIPs as sorbent was established for fast and selective enrichment of KMF and its structural analogue PA from the crude extract of M. torresiana and then KMF and PA were detected by HPLC-UV. The established method showed good performance and satisfactory results for real sample analysis. It also showed the feasi- bility of MMIPs for selective recognition of active structural analogues from complex herbal extracts. 相似文献
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目的 观察麦芽提取物对高泌乳素血症(HPRL)雌性小鼠泌乳素水平的影响,并初步分析麦芽提取物的化学成分,以确定麦芽中抗高泌乳素血症的活性部位。方法采用苯酚 硫酸法测定提取物中多糖的含量,采用紫外分光光度法测定提取物中黄酮的含量。采用甲氧氯普胺诱导雌性小鼠制备HPRL模型,给予麦芽提取物灌胃治疗。结果提取物中多糖和总黄酮含量分别为7.60%,0.17%,RSD分别为0.70%,1.70%;模型组小鼠造模前后血清PRL明显升高,差异有显著性(P<0.05);麦芽提取物高、中、低剂量组给药后小鼠血清PRL明显下降,均差异有显著性(均P<0.05)。组别之间以及各组与溴隐亭组之间差异无显著性。结论麦芽提取物能明显降低甲氧氯普胺诱导的HPRL雌性小鼠泌乳素水平,作用与溴隐亭相似。 相似文献
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不同寄主植物桑寄生总黄酮含量研究 总被引:6,自引:3,他引:3
目的 考察不同寄主植物的桑寄生总黄酮含量.方法 采用分光光度法测定寄生在16种不同寄主植物的桑寄生样品的总黄酮含量,并用正交实验的方法研究比较了不同提取条件对桑寄生总黄酮提取率的影响.结果 不同寄主植物的桑寄生茎枝的总黄酮含量为4.10~7.82 mg/g,其中以桑树为寄主的人工种植的桑寄生茎枝的总黄酮含量为最高;桑寄生叶总黄酮含量为18.33~32.08 mg/g,其中以夹竹桃为寄主的桑寄生叶的总黄酮含量最高.正交实验结果优选的提取条件茎枝是A_1B_2C_2D_3,即桑寄生茎枝0.5 g,乙醇浓度为60%,超声提取时间为30 min,超声提取温度为45℃,料液比1∶25;叶是A_2B_1C_2D_3,即桑寄生叶0.5 g,乙醇浓度为70%,超声提取时间为20 min,超声提取温度为45℃,料液比1∶25.结论 桑寄生总黄酮含量因寄主植物不同,其总黄酮含量表现出一定的差异性.优选的提取方法稳定、可靠、简洁,提取效率高. 相似文献
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从萝摩科植物喙柱牛奶菜(Marsdenia oreophila W.W.Sm)茎中首次分得 4种结晶性成分,经波谱分析(IR,MS,~1H-NMR,~(13)C-NMR)及物理化学方法分别鉴定为α-香树脂醇棕榈酸酯(α-amyrin palmitate,Ⅰ),α-香树脂醇己酸酯(α-amyrin caproate,Ⅱ),α-香树脂醇丁酸酯(α-amyrin bu-tyrate,Ⅲ)和β-谷甾醇(β-sitosterol,Ⅳ)。 相似文献
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