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采用HPLC法对广西十个不同产地的两面针中具有抗肿瘤活性的氯化两面针碱和具有镇痛活性的 L-芝麻脂素的含量进行了分析和比较。发现在不同产地的两面针中氯化两面针碱和L-芝麻脂素的含量差别 都较大,广西百色的两面针中氯化两面针碱含量和L-芝麻脂素的含量均最高,氯化两面针碱0.467%,L-芝麻 脂素0.160%;广西金秀的两面针中氯化两面针碱含量和L-芝麻脂素的含量均最低,氯化两面针碱0.0490%, L-芝麻脂素0.0370%。分析的色谱柱为HYPERSIL BDS C18,测定氯化两面针碱的条件为,流动相乙腈: 0.02 mol/L KH2PO4溶液(34:66),流速为1.0 mL/min,柱温40℃,检测波长329 nm,进样量为20μL;测定 L-芝麻脂素的条件为,流动相乙腈:水(50:50),流速为1.0 mL/min,柱温40℃,检测波长287 nm,进样量为 20μL。该研究为两面针在抗肿瘤药物和镇痛等方面的开发利用提供了可靠的理论依据,具有重要应用价值。 相似文献
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该研究选取广西不同类型的两面针为材料,通过查阅文献对两面针基原植物进行考证,用反相高效液相色谱法(RP-HPLC)对两面针原变种及变种中的5种活性成分进行定量分析。结果表明:(1)毛两面针[Zanthoxylum nitidum (Roxb) DC. f. fastuosum How ex Huang]早已并入两面针原变种[Z. nitidum (Roxb.)DC. var. nitidum];虽然毛两面针与毛叶两面针中文名称相似,但不可认为是同一个变种。(2) RP-HPLC结果显示两面针原变种及变种均不含毛两面针素。(3) 5种活性成分在不同类型中存在显著性差异。(4)根据5种活性成分含量数据,对9份两面针样品进行聚类分析,结果划分为4组,与两面针形态划分一致。这不仅理清了"毛叶两面针"与"毛两面针"存在的混淆问题,而且还比较了不同形态类型间的活性成分含量,为两面针质量控制和资源的合理应用开发提供了参考。 相似文献
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广西两面针野生种质资源调查研究 总被引:8,自引:3,他引:8
采用实地调查和走访调查相结合的方法对两面针在广西的野生种质资源情况进行调查。结果表明:广西民间使用两面针药材的基源植物有18种(含变种)。正品两面针有2个变种,原变种和毛两面针,原变种下又分为3个类型。两面针的植物形态和群落特征与生长的地形地貌有一定的相关性,原变种类型一通常生于丘陵地区,原变种类型二、类型三和毛两面针通常生于石山地区,各变种和类型的形态特征主要区别在叶片质地和植株的被毛情况。两面针生长的群落结构乔木层构成通常比较单一,灌木层、草本层相对复杂。由于生境破坏和不合理采收,广西两面针分布面积正逐年减小,经调查后估算,总蕴藏量(干重)约为2600t,资源短缺十分明显。建议采取各种积极的办法保护两面针野生种质资源,保证两面针的可持续利用。 相似文献
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两面针变种及类型间的小叶形态比较 总被引:1,自引:0,他引:1
为更好地分类和鉴定两面针原变种、毛两面针变种以及原变种的3个类型,对两面针2个变种及原变种3个类型的小叶形态特征进行了观察,并利用扫描电镜和解剖镜对叶片表皮和叶脉进行了显微观察和微形态研究。结果显示:两面针原变种各类型和毛两面针的植物形态主要区别在叶片质地和被毛情况,叶片质地在类型内较为稳定,是首要分类性状。毛两面针的叶表面特征与原变种区别明显,类型三有别于前两种类型。叶脉特征中毛两面针和类型一也与类型二和三有所不同。叶表面和叶脉的微形态均具有较好的分类意义和鉴别意义,支持《中国植物志》关于两面针2个变种以及3个类型的划分。 相似文献
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《天然产物研究与开发》2020,(8)
从滇产两面针的干燥根中分离得到12个化合物,通过其一维或二维核磁共振谱、质谱和理化性质的解析并结合文献鉴定了它们的结构,分别为9-去甲氧基两面针碱(1)、8-dehydroxyl-buesgenine(2)、6β-hydroxymenthyldihydronitidine(3)、花椒木精(4)、rhoifoline B(5)、两面针碱(6)、白屈菜红碱(7)、博落回碱(8)、白鲜碱(9)、γ-崖椒碱(10)、茵芋碱(11)和鹅掌楸碱(12)。其中,化合物1和2为新结构化合物。通过MTT法,首次评价了化合物1~12对黑色素瘤细胞WM9增殖的抑制活性,并发现化合物3和6对WM9细胞的增殖表现出较强的活性,半数抑制浓度(IC_(50))值分别为1.936μM和0.880μM,研究结果为抗肿瘤药物候选药物分子的发现提供了科学依据。 相似文献
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《天然产物研究与开发》2015,(4)
复合酶预处理两面针药材后,以氯化两面针碱、总生物碱得率和干膏收率为指标,采用正交试验和动态过程优化半仿生-超声法、渗漉法和回流法提取工艺,对其提取效果进行比较。各以4倍量枸橼酸-三乙胺60%乙醇缓冲液(p H 2.0、7.5和8.3)为溶剂,依次超声(250 W)提取15、12和9 min,氯化两面针碱得率2.52‰,总生物碱得率2.15%,干膏收率16.14%。以60%乙醇(5 g/L盐酸)为溶剂,浸润10 min后以10mL/min流速渗漉16倍量溶剂,氯化两面针碱得率2.30‰,总生物碱得率2.18%,干膏收率14.86%。分别用6、5和4倍量60%乙醇(5 g/L盐酸)依次回流15、12和9 min,氯化两面针碱得率2.46‰,总生物碱得率2.36%,干膏收率15.37%。半仿生-超声法和渗漉法比回流法经济,可为工业生产提供参考依据。 相似文献
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植物异喹啉生物碱(plant isoquinoline alkaloids,PIAs)包括吗啡、可待因、加兰他敏及小糵碱等药用活性产物和其他天然活性产物。从植物中提取异喹啉生物碱,受制于低含量、种植季节及提取方法。人们开始研究利用微生物异源合成和改造天然异喹啉生物碱,从而获得低成本的药用活性物质。异喹啉生物碱合成途径长,反应复杂,为实现微生物异源合成带来了诸多挑战。随着合成途径和酶的解析和鉴定,合成生物学技术为在微生物中合成异喹啉生物碱提供了可能。综述了PIAs合成途径解析的最新进展,以及微生物异源合成PIAs的代谢工程策略,讨论了目前存在的问题和未来的发展趋势。 相似文献
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Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons. 相似文献
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The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare
these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow
the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human
serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three
reconstituted reference serum samples by comparison with other methods and by the standard addition procedure.
The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision,
and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest
in the environment, the relatively delicate sample handling, and the high cost of the equipment. 相似文献
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G. V. Iyengar 《Biological trace element research》1987,12(1):263-295
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues
and body fluids.
A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements
of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or
partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America,
Australia, and New Zealand.
This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world.
It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several
elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different
countries reflected some interesting associations for elements, such as Mn and Zn.
Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples
requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as
Cu, Fe, and Zn were not available.
In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies
to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions,
which sadly lack data of any kind at present. 相似文献
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The unitary conductances and permeability sequences of the rat connexin40 (rCx40) gap junction channels to seven monovalent cations and anions were studied in rCx40-transfected neuroblastoma 2A (N2A) cell pairs using the dual whole cell recording technique. Chloride salt cation substitutions (115 mM principal salt) resulted in the following junctional maximal single channel current-voltage relationship slope conductances (γj in pS): CsCl (153), RbCl (148), KCl (142), NaCl (115), LiCl (86), TMACl (71), TEACl (63). Reversible block of the rCx40 channel was observed with TBA. Potassium anion salt γj are: Kglutamate (160), Kacetate (160), Kaspartate (158), KNO3 (157), KF (148), KCl (142), and KBr (132). Ion selectivity was verified by measuring reversal potentials for current in rCx40 gap junction channels with asymmetric salt solutions in the two electrodes and using the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The permeabilities relative to Li+ are: Cs+ (1.38), Rb+ (1.32), K+ (1.31), Na+ (1.16), TMA+ (0.53), TEA+ (0.45), TBA+ (0.03), Cl− (0.19), glutamate− (0.04), and NO3− (0.14), assuming that the monovalent anions permeate the channel by forming ion pairs with permeant monovalent cations within the pore thereby causing proportionate decreases in the channel conductance. This hypothesis can account for why the predicted increasing conductances with increasing ion mobilities in an essentially aqueous channel were not observed for anions in the rCx40 channel. The rCx40 effective channel radius is estimated to be 6.6 Å from a theoretical fit of the relationship of relative permeability and cation radius. 相似文献
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A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability. 相似文献
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The aim of this report has been to present results concerning analytical quality controls of Hg analysis of fish and sediment, analyses of Fe, Ca, total-P, K, pH, alkalinity, conductivity, colour and hardness (Ca + Mg) of lake water samples. Despite the fact that these are standard parameters in many regular water control programs, there are major differences in the reliability with which these parameters can be determined. The focus here is on an overall inter-laboratory comparison between the parameters. Six laboratories have been involved in the analysis. Selected results: pH gives the lowest (average) relative standard deviation (error), about 2 %; conductivity gives an error of about 5–7 %; alkalinity yields an average error of as much as 13–25 %, which is the largest among the parameters studied here; colour also gives a high error, 9–15 %; hardness gives a relative standard deviation of about 6–7 %. Of the other parameters (i. e., Hg, Fe, Ca and P), Hg gives the best reliability and Fe and P the lowest. To have knowledge of the reliability of the analytical data is of paramount importance in most control programs and research projects. 相似文献
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We investigated the uptake of inorganic elements (Be, Na, Mg, K, Ca, Sc, Mn, Co, Zn, Se, Rb, Sr, Y, Zr, Ce, Pm, Gd, and Hf)
and the effect of Ca on their uptake in carrots (Daucus carota cv. U.S. harumakigosun) by the radioactive multitracer technique. The experimental results suggested that Na, Mg, K, and
Rb competed for the functional groups outside the cells in roots with Ca but not for the transporter-binding sites on the
plasma membrrane of the root cortex cells. In contrast, Y, Ce, Pm, and Gd competed with Ca for the transporters on the plasma
membrane. The selectivity, which was defined as the value obtained by dividing the concentration ratio of an elemental pair,
K/Na, Rb/Na, Be/Sr, and Mg/Sr, in the presence of 0.2 and 2 ppm Ca by that of the corresponding elemental pair in the absence
of Ca in the solution was estimated. The selectivity of K and Rb in roots was increased in the presence of Ca. The selectivity
of Be in roots was not affected, whereas the selectivity of Mg was increased by Ca. These observations suggest that the presence
of Ca in the uptake solution enhances the selectivity in the uptake of metabolically important elements against unwanted elements. 相似文献
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The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid. 相似文献
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Vladimir Zaichick Sofia Zaichick Vasilii Karandashev Sergey Nosenko 《Biological trace element research》2009,129(1-3):107-115
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs. 相似文献