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1.
滕道祥  马利华  秦卫东 《安徽农业科学》2010,(25):13703-13704,13706
[目的]提取牛蒡多酚,并进行抗氧化性试验。[方法]采用不同预处理方法处理牛蒡,并提取牛蒡多酚物质;采用电子顺磁共振技术(EPR),分别检测不同浓度牛蒡多酚对DPPH自由基的清除作用。[结果]Vc浸泡处理后,牛蒡多酚提取率最高;牛蒡多酚浓度与清除效用呈线性关系,其半数清除率EC50为202.04μg/ml。[结论]Vc浸泡处理后的牛蒡多酚在一定浓度范围内具明显的清除DPPH自由基作用。EPR检测自由基方法快速、灵敏。  相似文献   
2.
目的研究蒸煮腌肉色素(CCMP)的结构。方法利用电子顺磁共振(EPR)、高效液相色谱和高分辨率电喷雾质谱联用(HPLC-ESI-HR-MS)、傅立叶红外光谱(FTIR)和红外激光拉曼光谱4种波谱综合分析鉴定。结果CCMP丙酮溶液的EPR图谱出现卟啉铁3d轨道上的未成对电子与一个-NO基团的14N原子的核自旋发生相互作用,在g3处产生3个一组信号的超精细分裂。FTIR和拉曼图谱分别在1653.31和1656.69cm-1出现5配位的CCMP的Fe-NO结构的特征吸收,CCMP的ESI-HR-MS图谱中未出现二亚硝酰亚铁卟啉血色原的分子离子峰,而出现一亚硝酰亚铁卟啉血色原不同碎片离子的质荷比。结论本研究认为CCMP的结构为五配位的一亚硝酰亚铁卟啉血色原。  相似文献   
3.
试验旨在建立一种高效液相色谱检测方法,同时测定乙酰氨基阿维菌素(EPR)缓释注射剂的主成分与有关物质,采用外标法计算主成分的含量,采用自身对照法计算有关物质的含量。色谱柱为Phenomenex Luna 5 μ-C8-100A 250 mm×4.60 mm,5 μm;色谱条件为:流动相为乙腈-0.1%高氯酸水溶液,梯度洗脱,流速为1.5 mL/min,检测波长为245 nm,柱温为35 ℃,进样量为20 μL。结果表明,EPR缓释注射剂主成分与杂质分离度良好,B1a与B1b之间分离度>3;在EPR浓度为1.5625~1 000 μg/mL的范围内线性关系良好;EPR的检测限与定量限分别为0.01和0.34 μg/mL,3种精密度的相对标准偏差(RSD)均<2%,稳定性的RSD为0.28%,加样回收率为102.54%,且RSD为3.14%(n=9)。耐用性试验表明,EPR缓释注射剂主成分的分离度均>1.5,理论塔板数>4 500,表明该检测条件的耐用性良好。3批样品中,EPR缓释注射剂含量的平均值为102.60%,B1b占B1a与B1b之和的1.68%,总杂质的平均含量为2.57%。建立的EPR缓释注射剂中主成分含量与有关物质的测定方法具有简便、专属性强、灵敏度高、结果准确等特点,可用于EPR缓释注射剂的质量控制。  相似文献   
4.
将810只初生淮北麻鸡随机分为27组,采用2因素3水平试验设计,日粮代谢能分别为10.90MJ/kg(低)、11.40MJ/kg(中)和11.90MJ/kg(高),粗蛋白分别为16.4%(低)、17.7%(中)和19.0%(高),研究0~4周龄淮北麻鸡的能量和蛋白质需要量。结果表明,日粮能量、蛋白质以及两者的交互作用均显著影响0~4周龄淮北麻鸡的生长性能、体成分和能量、蛋白质的沉积(P<0.05)。低能量+高蛋白组采食量显著高于其他处理组(P<0.01)。日粮能量由10.90MJ/kg提高到11.40MJ/kg,采食量下降,当继续提高能量时,对采食量的影响不明显,这一规律不受日粮蛋白质的影响;高能量+高蛋白组和低能量+低蛋白组生长性能高于其他组,中等能量组以及低能量中高蛋白组最差(P<0.01)。高能量+高蛋白质组饲料转化率显著优于其他各组。高能量+低蛋白质组组织中脂肪含量显著高于其他处理组,中能量+中蛋白质组和低能量+高蛋白质组最低(P<0.01)。各处理组中,低能量+低蛋白质组和高能量+低蛋白质组能量沉积率最高,中能量、中高蛋白质组最低(P<0.01)。0~4周龄淮北麻鸡日粮适宜代谢能和蛋白质分别为11.90MJ/kg、17.7%或10.90MJ/kg、16.4%。  相似文献   
5.
氮离子束等诱变机理研究(一)   总被引:7,自引:0,他引:7  
选用小麦品种(系)、远缘杂种和四倍体黑麦等供试样品,经N+束、C。60γ-ray、2660A紫外激光等七种不同诱变源各高低两种剂量处理后,分析不同诱变源与小麦试样间的互作效应,据电子顺磁共振(EPR)波谱特征和发芽率的差异,首先发现N+与γ-ray一样对发芽率有明显的影响,而N+处理的所有样品,其EPR谱信号都较强,超过中子、紫外激光甚至γ-ray处理的结果。这可能表明低能N+束引起物体内自由基信号强度增大,是诱导植物内部损伤、分子集团重组以致构成遗传变异的基础。  相似文献   
6.
依据《中华人民共和国兽药典》与《兽药研究技术指导原则汇编》等相关指导要求,对乙酰氨基阿维菌素(EPR)注射用缓释剂进行外观、黏度、pH、水分、密度、内毒素、含量及有关物质检测,建立EPR注射用缓释剂的质量标准并比较与参比制剂的药学等效性。含量与有关物质检测方法为使用ZORBAX Eclipse Plus C18柱(2.1 mm×50 mm,1.8 μm);流动相:甲酸:水:乙腈(0.04 mL:40 mL:60 mL);流速:0.4 mL/min;检测波长:245 nm;柱温:35 ℃;进样量:2 μL。在37 ℃,转速为50 r/min,0.5% SDS的PBS缓冲液条件下,比较自研与原研EPR注射用缓释剂的药学等效性。EPR注射用缓释剂外观澄清透明,平均相对黏度为46.45 mPa·s,平均pH为6.88,制剂中不含水分,密度为1.13 g/cm3,内毒素满足<0.1 EU/mL限度,含量>5%的标示值,有关物质的量<5%,检测结果均符合注射剂制剂要求;在同一条件下释放31 d后,自研与原研EPR注射用缓释剂累积释放量均超过80%,且自研与原研的相似因子(f2)值>50。自研EPR注射用缓释剂的检测结果均符合注射剂标准,自研与原研EPR注射用缓释剂具有药学等效。  相似文献   
7.
In tropical soils, the high turnover rate and mineralization of organic matter (OM) associated with intensive agricultural use, generally leads to faster soil degradation than that observed in temperate climatic zones. The application of sewage sludge to the soils is one proposed method of maintaining soil organic matter, and is also an alternative method of disposing of this waste product. As well as containing large quantities of OM, sludge is also a significant source of supplementary nitrogen, phosphorus and other essential nutrients for plant growth. However, it is necessary to understand the qualitative and quantitative changes that take place in the OM in soil treated with sewage sludge. The approach of the present study was intended to identify possible structural changes caused by sewage sludge applications on soil humic acids (HAs). The HAs extracted from a Typic Achrortox under sewage sludge applications were characterized by electron paramagnetic resonance (EPR) spectroscopy. The soil samples were collected from a field experiment designed to evaluate the effects of different doses of sewage sludge on corn growth and development in Brazil. The sewage sludge originated from urban waste treated at the sewage sludge treatment station in the city of Franca, state of Sao Paulo, Brazil. The following soil treatments were studied: control (non-cultivated soil under natural vegetation (NC)), control soil amended with NPK (conventional corn fertilization) and four treatments N1, N2, N4 and N8 with applications of 3.5, 7, 14 and 28 Mg ha−1 of sewage sludge (dry matter), respectively. HAs were extracted from the surface layer using the methodology of the International Humic Substance Society (IHSS). Fe3+ and VO2+ ions complexed with HAs, and also semiquinone-type free radical (SFR) at concentrations of approximately 2.0 × 1018 spins g−1 HA were identified in EPR spectra. The levels of SFR were lower for treatments where the applied sewage sludge doses were equivalent to four and eight times the normal doses of N mineral fertilization, reaching values of 1.7 × 1018 and 1.24 × 1018 spins g−1 HA, respectively. The observed decrease in SFR content as sewage sludge dose was increased, was probably associated with the incorporation of less aromatic components into HAs originating from the sewage sludge.  相似文献   
8.
在节酸磷肥的生产过程中,在磷矿粉中加入一定比例的添加剂,制成3种新型改性磷肥.化学分析结果表明,改性磷肥有效磷中水溶性磷比例下降;盆栽试验结果显示,在等重条件下,3种改性磷肥的玉米生物量较过磷酸钙均有较大幅度的增加;运用电子顺磁共振(EPR)对改性磷肥和植株的顺磁元素进行了研究,发现改性磷肥的EPR谱与磷矿粉相比则发生较大变化,经改性后,改性磷肥Mn2+的超精细结构谱峰消失,说明磷矿粉经改性后其结构趋于无序.改性磷肥的施用能改善植物对微量元素Fe3+、Mn2+的均衡吸收并使Fe3+、Mn2+在植物体内分布更为有序,是其生物量增产的内因.  相似文献   
9.
【目的】分析不同酿酒葡萄品种所酿制的干红葡萄酒抗氧化性的差异及其与总酚含量之间的关系。【方法】利用电子顺磁共振波谱仪(Electron Paramagnetic Resonance, 简称EPR)和福林-肖卡法(Folin-Ciocalteu,简称FC)分别对河北沙城产区5个单品种干红葡萄酒检测DPPH清除率和总酚含量,筛选适当的EPR试验条件。【结果】干红葡萄酒具有很强的抗氧化能力,在样品稀释200倍、反应时间5 min的条件下,各样品清除DPPH自由基的能力以赤霞珠葡萄酒为最强72.31%,宝石解百纳72.23%,梅鹿辄68.31%,西拉和增芳德分别为59.03%和56.34%。梅鹿辄、宝石解百纳和赤霞珠葡萄酒的总酚含量,分别为3 044.43、3 026.92和2 886.81 mg•L-1。西拉和增芳德葡萄酒的总酚含量相对较低,分别为2 085.51 mg•L-1和1 647.64 mg•L-1。【结论】电子顺磁共振法可以简便、快速检测干红葡萄酒的抗氧化性,不同单品种干红葡萄酒DPPH清除能力表现明显不同,自由基清除率与总酚含量之间存在线性正相关,回归方程y=0.01116x+37.327665,相关系数rGAE/DPPHequiv=0.91753。  相似文献   
10.
Although high oxygen consumption in skeletal muscle may result in severe oxidative stress, there are no direct studies that have documented free radical production in horse muscles after intensive exercise. To find a new parameter indicating the muscle adaptation state for the training of Thoroughbred horses, we examined free radical formation in the muscle by using electron paramagnetic resonance (EPR). Ten male Thoroughbred horses received conventional training for 18 weeks. Before and after the training period, all horses performed an exhaustive incremental load exercise on a 6% incline treadmill. Muscle samples of the middle gluteal muscle were taken pre-exercise and 1 min, 1 hr, and 1 day after exercise. Muscle fiber type composition was also determined in the pre-exercise samples by immunohistochemical staining with monoclonal antibody to myosin heavy chain. We measured the free radical in the muscle homogenate using EPR at room temperature, and the amount was expressed as relative EPR signal intensity. There was a significant increase in Type IIA muscle fiber composition and a decrease in Type IIX fiber composition after the training period. Before the training period, the mean value of the relative EPR signal intensity showed a significant increase over the pre-exercise value at 1 min after the exercise and an incomplete recovery at 24 hr after the exercise. While no significant changes were found in the relative EPR signal intensity after the training period. There was a significant relationship between percentages of Type IIA fiber and change rates in EPR signal intensity at 1 min after exercise. The measurement of free radicals may be useful for determining the muscle adaptation state in the training of Thoroughbred horses.  相似文献   
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