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1.
太空诱变桔梗的X射线荧光光谱的测定分析   总被引:6,自引:3,他引:3  
选用X射线荧光光谱法(XRF),对我国独创的第4代太空诱变育种桔梗、地面组桔梗和桔梗对照品的元素种类和含量进行测定与分析。结果表明,太空组桔梗中与桔梗理气、化痰功效相关的Zn,Mn,Fe等元素分别比地面组提高了1.9,2.4,0.6倍,其中Zn和Mn元素比对照品分别提高了0.6和1.9倍。即与地面组相比,太空组桔梗更趋近于或优于对照品桔梗。太空组桔梗中多种元素指标得到了大幅度的提升和优化。XRF方法具有方便快捷、灵敏度高、元素和含量范围广以及再现性好等特点,可用于一切能制成粉末样品的其他中药的测定分析。  相似文献   
2.
邢倩倩  傅青  金郁  梁鑫淼 《色谱》2014,32(7):767-772
建立了亲水/反相二维色谱用于制备桔梗中三萜皂苷单体的方法。桔梗经水煮醇沉、反相和亲水两种模式的固相萃取后得到三萜皂苷类组分。选定XAmide色谱柱(150 mm×20 mm,5 μm),以乙腈和水为流动相,在亲水色谱模式下进行组分制备。选择时间触发模式,以1 min为单位进行馏分收集,得到6~25 min之间的20个三萜皂苷精细组分。以第18个馏分(JG23)为例,在反相色谱模式下采用Atlantis Prep T3色谱柱(100 mm×30 mm,5 μm)制备,得到两个单体化合物。通过质谱和核磁共振对其进行定性,确定分别为deapi-platycoside E和platycoside E。实验结果表明,该制备方法具有好的正交选择性,对于复杂样品中三萜皂苷类化合物的分离纯化有一定的借鉴意义。  相似文献   
3.
Studies on polyphenols and flavonoids in natural products reveal benefits in the prevention of multiple diseases. Proper extraction, treatment of extracts, and quantification of polyphenols and flavonoids demand attention from the scientific community in order to report more specific biological action. Total polyphenol content (TPC) and total flavonoid content (TFC) (measured at three different times) of ethanol, methanol and acetone extracts of Mauritia flexuosa (aguaje) and Theobroma grandiflorum (copoazú) fresh pulp, from the Colombian Amazon region, were evaluated with the purpose of focusing in the polyphenol/flavonoid proportion and its effective antioxidant activity. This objective could help to explain specific flavonoid biological action based on higher flavonoid proportion rather than higher total polyphenol content. Differences in extracting solvents resulted in statistically significant different yields; the highest TPC was observed with acetone 70% in Mauritia flexuosa and ethanol 80% for T. grandiflorum. The best flavonoid/polyphenol ratio in M. flexuosa was about 1:2.4 and 1:12.8 in T. grandiflorum and the antioxidant efficacy was proportionally higher for flavonoids extracted from T. grandiflorum. HPLC analysis revealed 54 µg/g of the flavonoid kaempferol in M. Flexuosa and 29 µg/g in T. grandiflorum. Further studies evaluating this proportionality, in seeds or peel of fruits, as well as, other specific biological activities, could help to understand the detailed flavonoid action without focusing on the high total polyphenol content.  相似文献   
4.
In vitro cultures of scarlet flax (Linum grandiflorum L.), an important ornamental flax, have been established as a new possible valuable resource of lignans and neolignans for antioxidant and anti-inflammatory applications. The callogenic potential at different concentrations of α-naphthalene acetic acid (NAA) and thidiazuron (TDZ), alone or in combinations, was evaluated using both L. grandiflorum hypocotyl and cotyledon explants. A higher callus induction frequency was observed on NAA than TDZ, especially for hypocotyl explants, with a maximum frequency (i.e., 95.2%) on 1.0 mg/L of NAA. The presence of NAA (1.0 mg/L) in conjunction with TDZ tended to increase the frequency of callogenesis relative to TDZ alone, but never reached the values observed with NAA alone, thereby indicating the lack of synergy between these two plant growth regulators (PGRs). Similarly, in terms of biomass, NAA was more effective than TDZ, with a maximum accumulation of biomass registered for medium supplemented with 1.0 mg/L of NAA using hypocotyls as initial explants (DW: 13.1 g). However, for biomass, a synergy between the two PGRs was observed, particularly for cotyledon-derived explants and for the lowest concentrations of TDZ. The influence of these two PGRs on callogenesis and biomass is discussed. The HPLC analysis confirmed the presence of lignans (secoisolariciresinol (SECO) and lariciresinol (LARI) and neolignan (dehydrodiconiferyl alcohol [DCA]) naturally accumulated in their glycoside forms. Furthermore, the antioxidant activities performed for both hypocotyl- and cotyledon-derived cultures were also found maximal (DPPH: 89.5%, FRAP 866: µM TEAC, ABTS: 456 µM TEAC) in hypocotyl-derived callus cultures as compared with callus obtained from cotyledon explants. Moreover, the anti-inflammatory activities revealed high inhibition (COX-1: 47.4% and COX-2: 51.1%) for extract of hypocotyl-derived callus cultures at 2.5 mg/L TDZ. The anti-inflammatory action against COX-1 and COX-2 was supported by the IC50 values. This report provides a viable approach for enhanced biomass accumulation and efficient production of (neo)lignans in L. grandiflorum callus cultures.  相似文献   
5.
Platycodon grandiflorum is an edible and medicinal plant, and polysaccharides are one of its important components. To further improve the utilization rate of P. grandiflorum, we investigated the effects of four different extraction methods, including hot water, ultrasonic-assisted, acid-assisted, and alkali-assisted extractions, on the polysaccharides, which were named PG-H, PG-U, PG-C, and PG-A. The findings indicated that the extraction method had a significant impact on the yield, characteristics, and immunoregulatory activity. We observed that the yields decreased in the following order: PG-H, PG-U, PG-C, and PG-A. Galacturonic acid, glucose, galactose, and arabinose were the most prevalent monosaccharides in the four PGs. However, their proportions varied. In addition, the difference between the content of glucose and galacturonic acid was more significant. PG-U had the highest glucose content, whereas PG-C had the lowest. Galacturonic acid content was highest in PG-A, while the lowest in PG-U. The molecular weight decreased in the order of PG-U, PG-H, PG-C, and PG-A; the particle size was in the order of PG-U, PG-A, PG-H, and PG-C. Moreover, the extraction method had a great impact on immunoregulatory activity. The ability to stimulate the immune function of macrophages was as follows: PG-A > PG-C > PG-U > PG-H. The results indicated that PGs, with lower molecular weights and higher GalA content, exhibited better immune-stimulating activity. And more important the AAE method was a good way to extract polysaccharides from Platycodon grandiflorum for use as a functional product and immunological adjuvant.  相似文献   
6.
分别采用湿法、干法和先灰化再用硝酸-高氯酸(φ,4∶1)常压微沸条件下消解桔梗样品,用火焰原子吸收法测定栽培桔梗中的金属元素K,Mg,Ca,Cu,Zn,Mn,Fe,Co,Ni,Cd,Cr和Pb含量。研究了不同消化方法对测定栽培桔梗中的金属元素含量的影响以及测定不同元素的仪器最佳工作条件,并做了方法的准确度和精密度考察。结果表明,不同消化方法对测定Mg和Ca有显著影响,不同消化方法测定的栽培桔梗中K, Mg, Ca, Mn, Fe, Cu, Zn的平均含量分别为13 226.32, 922.57, 1 710.72, 9.23, 336.66, 8.75, 19.62 μg·g-1;Ni,Co,Cd,Cr和Pb未检出。方法的加标回收率为95.45%~105.50%, 相对标准偏差(n=9)为0.34%~5.78%。选择先灰化再用混酸消化测定栽培中药材金属元素含量,方法简单易行,结果令人满意。  相似文献   
7.
A new triterpenoid saponin from the roots of Platycodon grandiflorum   总被引:1,自引:0,他引:1  
A new triterpenoid saponin, 3-O-β-D-glucopyranosyl 16-oxo-platycodigenin 28-O-β-D-apiofuranosyl-(1→3)-β-D-xylopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyra-nosyl ester, was isolated from the roots of Platycodon grandiflorum, together with three known saponins, including platycodin D, deapio platycoside E and platycoside E. The structure of the new compound, named 16-oxo-platycodin D, was elucidated on the basis of spectroscopic data.  相似文献   
8.
Curcuma aromatica (Family Zingiberaceae) is an important medicinal plant and its rhizome has been used as a traditional Chinese medicine possessing activities of anticancer, antioxidation and bile secretion promotion. Curdione, compound 1, with a germacrane skeleton is one of its major active constituents. Recently, curdione was reported to exhibit hepatoprotective activity 1, 2. In an endeavor to find new chemical entities, we examined the plant cell suspension cultures of Platycodon grandi…  相似文献   
9.
Cupuassu (Theobroma grandiflorum Schum.) is a popular Amazonian fruit because of its intense aroma and nutritional value, whose lipid fraction is alternatively used in cosmetics. To preserve active principles and ensure their controlled release, extract was microencapsulated by spray drying. Influence of spray-drying conditions on microencapsulation of cupuassu seed by-product extract was investigated according to a 33-Box Behnken factorial design, selecting inlet temperature, maltodextrin concentration and feed flowrate as independent variables, and total polyphenol and flavonoid contents, antiradical power, yields of drying and microencapsulation as responses. Fitting the results by second-order equations and modelling by Response Surface Methodology allowed predicting optimum conditions. Epicatechin and glycosylated quercetin were the major microencapsulated flavonoids. Microparticles showed satisfactory antiradical power and stability at 5 °C or under simulated gastrointestinal conditions, thus they may be used to formulate new foods or pharmaceuticals.  相似文献   
10.
建立分散固相萃取-气相色谱法测定中药材桔梗中11种有机氯农药的残留量的测定方法。采用Agilent Sampliq QuEChERS分散固相萃取包进行样品处理。色谱条件为:HP-1701弹性石英毛细管色谱柱(30 m×0.32mm,25μm),进样口温度为250℃,检测器为Ni63电子捕获检测器,检测器温度为300℃,不分流进样,程序升温,高纯氮气为载气。8种有机氯农药在0.02~0.2 mg/L范围内与色谱峰面积线性关系良好(r0.999),其检出限范围为0.0015~0.0098 mg/kg,该方法的回收率为82.3%~104.1%,相对标准偏差不大于2.5%(n=5)。  相似文献   
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