共查询到20条相似文献,搜索用时 171 毫秒
1.
2.
3.
《食品与药品》2017,(5)
目的比较紫外-可见分光光度法和柱前衍生高效液相色谱法(HPLC)两种方法测定对乙酰氨基酚注射液中抗氧剂盐酸半胱氨酸的含量差异,研究盐酸半胱氨酸含量测定方法的可靠性。方法紫外-可见分光光度法:通过盐酸半胱氨酸与酸性茚三酮溶液反应生成红色产物,在559 nm波长处测定吸收度;柱前衍生HPLC:以2,4-二硝基氟苯为衍生化试剂,与对乙酰氨基酚注射液在60℃水浴暗处反应,HPLC测定。采用Agilent extend C_(18)(250 mm×4.6 mm,5μm)色谱柱,以乙腈-0.014 mol/L磷酸氢二钾溶液(用磷酸溶液调pH 8.2)(35:65)为流动相,流速1.0 mL/min,检测波长360 nm。结果使用紫外-可见分光光度法,测得3批样品的含量分别为0.24,0.24,0.23 mg/mL。使用柱前衍生HPLC,测得3批样品的含量分别为0.23,0.24,0.23 mg/mL。结论紫外-可见分光光度法和柱前衍生HPLC均可准确测定对乙酰氨基酚注射液中的抗氧剂盐酸半胱氨酸的含量。 相似文献
4.
通过L9(34)正交实验对杜仲粉丝中活性成分绿原酸和总黄酮含量检测的最佳同时提取条件进行了优化。结果表明:杜仲粉丝中活性成分最佳同时提取条件为以30%乙醇为溶剂,于60℃浸提2h;采用紫外分光光度法检测绿原酸的最大吸收波长为325nm,标准曲线为:A=0.0491C+0.0068,R2=0.9998;采用紫外分光光度法检测总黄酮的最大吸收波长为500nm,标准曲线为:A=0.0073C+0.0221,R2=0.9997;测得杜仲活性成分绿原酸含量0.1491%、总黄酮含量0.5927%。 相似文献
5.
紫外分光光度法测定调味品中苯甲酸 总被引:4,自引:0,他引:4
探讨了紫外分光光度法测定调味品中苯甲酸含量 ,通过正交实验确定水浴温度 10 0℃、馏液体积 5 0mL、水浴时间 10min为最佳提取氧化条件。该方法检测成本低廉 ,测定程序方便快捷 ,不需大型仪器和特殊试剂 ,可应用于一般工厂实践中。 相似文献
6.
7.
8.
9.
《中国调味品》2016,(9)
研究了超声微波协同萃取法提取食品中亚硝酸盐的最佳提取条件,并用双波长分光光度法测定亚硝酸盐的含量。结果表明:超声微波协同萃取最佳工艺参数为在pH 7.5、料液比1∶10、提取功率50W条件下提取6min;与传统水浴提取法比较,提取率增加了3.02%~14.60%。双波长分光光度法测定条件:pH值在4~9范围内,硝酸盐和亚硝酸盐测定波长分别为202,209nm,线性范围分别为0.04~0.2,0.02~0.2μg/mL。应用于食品样品测定,相对标准偏差为1.57%~4.56%,加标回收率为95.6%~107.5%,其测定结果与国标盐酸萘乙二胺显色法比较,相对误差在0.11%~6.5%。 相似文献
10.
11.
世界油料、油脂供需及贸易格局分析 总被引:1,自引:0,他引:1
总结近几年世界油料、油脂生产、消费以及贸易格局变动特征,分析了大豆、油菜籽、花生、棕榈油、大豆油、菜籽油及葵花籽油的主产国和需求国之间供需贸易情况,以及未来世界油脂市场供求贸易关系的演变趋势。分析表明:未来发展中国家对油料、油脂市场的影响日趋显著;从全球视角来看,油料主要供给国之间以及主要需求国之间存在相互竞争关系,具体表现为供给国供应能力和需求国购买力相互间的权衡。 相似文献
12.
D'Arco G Blasi F Cossignani L Di Giacomo F Ciavardelli D Ventura F Scipioni S Simonetti MS Damiani P 《Journal of the science of food and agriculture》2012,92(4):952-959
BACKGROUND: Rabbit meat has excellent nutritive properties. The purpose of this study was to characterize rabbit meat and offal; in particular, the lipid fraction was studied in order to evaluate total and positional fatty acid (FA) compositions of triacylglycerol (TAG) and phosphatidylcholine (PC) fractions. Eight samples of weaned and eight of fattened rabbits were considered. RESULTS: Fattened rabbit meat contained slightly higher protein percentage content (P < 0.05) in comparison to weaned (20.1% versus 18.0%). Calcium content was higher in meat than in offal, unlike sodium, iron, zinc, manganese and copper. The cholesterol content in offal was much higher than in meat. FA profiles of total lipid showed a high percentage of unsaturated fatty acids and an n‐6/n‐3 ratio of 10.3 for fattened rabbit meat. Stereospecific analysis of TAG and PC was carried out on an eight‐sample pool of each meat and offal from weaned and fattened rabbits. In all samples the sn‐2‐position was prevalently esterified with oleic and linoleic acids in TAG, with polyunsaturated fatty acids in PC. CONCLUSION: Lipids from rabbit meat presented higher content of monounsaturated FA and lower n‐6/n‐3 ratio in comparison to offal, which was characterized by higher cholesterol and mineral levels. Copyright © 2011 Society of Chemical Industry 相似文献
13.
14.
通过对兔毛纤维进行改性处理改善其可纺性,并与羊毛、氨纶和其他原料等混合,采用半精纺和精梳工艺相结合生产羊兔毛精梳弹力纱,生产出羊兔毛精梳弹力织物。根据兔毛纤维的特点,为了达到理想的针梳效果,对针梳机设备作了改进,使纱线的质量和条干均匀度良好。通过对原料的选择、混纺比的确定、纺纱、织造、后整理等一整套工艺路线和技术参数的选择,研制的羊兔毛精纺弹力织物外观华贵,手感柔软滑糯,具有独特风格。 相似文献
15.
野杂种猪肉品质特性研究及应用进展 总被引:3,自引:0,他引:3
本文综述了野杂种猪肉品质特性的研究及利用状况,分析了大面积推广应用野杂种猪可能出现的风险,并提出了开展野杂种猪肉品质特性选育的方向。 相似文献
16.
17.
18.
19.
蔬菜抗氧化能力及与酚酸和总黄酮相关性研究 总被引:1,自引:0,他引:1
分析常见蔬菜总抗氧化活性,探讨蔬菜抗氧化能力与酚酸、总黄酮的相关性。采用ABTS、DPPH与FRAP法测定10种常见蔬菜的抗氧化能力,采用Folin-Ciocalteu法测总酚酸,硝酸铝-亚硝酸钠-氢氧化钠法测总黄酮,采用matlab软件进行拟合抗氧化与酚酸、总黄酮的函数方程。结果表明:抗氧化活性与主要抗氧化物质(酚酸和黄酮)的函数关系为Z=-137.743 2-0.918 2 X2+0.211 2Y2-0.422 9 XY+52.843 5 X+2.229 9Y。当总黄酮在6~26mg/100g时,总黄酮、酚酸的量对总抗氧化活性有促进作用;而在27~54mg/100g范围内,总黄酮和酚酸的含量对总抗氧化能力具有一定的抑制作用。 相似文献
20.
Tetrahydrocurcumin (THC, 1) and zingerone (2) are biologically active molecules originating from the important spices turmeric and ginger, respectively. Novel quinoline derivatives of THC and zingerone have been synthesised by an efficient protocol involving their reaction with substituted 2-aminobenzophenones and 2-aminoacetophenone. Radical-scavenging activities (RSA) of THC, zingerone and their quinoline derivatives were evaluated. The amino-substituted quinoline derivative of THC, 1e, showed antioxidant activity superior to those of 1 and 1a. Derivatives 1b, 1c, 1d and 1f exhibited relatively lower RSA at equimolar concentrations (∼50–55 μmol). A similar trend was also seen in zingerone (2) and its derivatives (2a–2e), with 2e displaying the best RSA. Derivatives of THC (1a–1f) showed stronger antimicrobial activity than THC (1) against Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Yersinia enterocolitica. Also, derivatives of zingerone (2b–2e) exhibited lower minimum inhibitory concentrations (MIC) values than zingerone (2) and its derivative, 2a for both Gram-positive and Gram-negative bacteria. The molecules may have potential pharmacological applications. 相似文献