高效液相色谱法测定糖肽酮萜素中低聚糖的含量

采用高效液相色谱法（HPLC），分离柱选用ODS色谱柱，以纯水为洗脱液，用示差折光检测。测定了饲料添加剂和功能食品中低聚糖的含量，即蔗糖、水苏糖和棉子糖。本法具有流动相价廉、无污染、快速简便和稳定性好的特点，色谱柱使用寿命长。     

含乳食品中常用防腐剂、甜味剂同时检测方法的研究

本文对一些含乳食品中的常用防腐剂(苯甲酸、山梨酸、脱氢乙酸)、甜味剂(安赛蜜、阿斯巴甜、糖精钠)同时检测方法的建立进行了研究。通过对检测波长、流动相及流动相比例的选择,确定的液相色谱检测条件是:流动相为乙腈:甲醇:0.01mol/L乙酸铵=4:3:93,流速为1.0m L/min,柱温为30℃,进样量为10μL,色谱样为Agilent C18液相色谱柱,高效液相色谱紫外检测波长为205nm。结果在最佳色谱条件下,六种化合物的线性关系良好,相关系数为0.9991~0.9998,实现了20min内对六种化合物的同时测定。     

高效液相色谱法检测乳制品中三聚氰胺的分析

本文采用国家标准法中高效液相色谱法检测了乳及乳制中的三聚氰胺,经过反复使用和多次试验,从样品处理、净化、仪器测定3个方面,对国家标准中要求不详之处,进行了补充和改进。对用液相色谱法检测三聚氰胺所用色谱柱和流动相进行了优选,将乳及乳制品中与三聚氰胺出峰时间重叠的组分进行了完全分离。     

UPLC和HPLC法检测猪肉中磺胺类药物残留的比较

比较了超高效液相色谱法与高效液相色谱法测定猪肉中磺胺类药物残留的结果。采用农牧发[2001]38号动物源食品中磺胺类药物残留的检测方法有关标准,将原高效液相色谱方法转换并优化为超高效液相色谱方法。高效液相色谱方法色谱柱为Waters Symmetry C18柱(4.6 mm×250 mm,5μm),流动相:乙腈-甲醇-水-乙酸(2∶2∶9∶0.2),流速:1 mL/min,进样量:50μL;超高效液相色谱方法色谱柱为Waters Acquity UPLC BEH RP18柱(2.1 mm×50 mm,1.7μm),流动相:乙腈-甲醇-水-乙酸(2∶2∶10∶0.2),流速:0.4 mL/min,进样量:5μL。结果表明超高效液相色谱方法能够替代高效液相色谱分析方法测定猪肉中磺胺类药物残留,既加快了分析速度,达到了样品分析的高通量,减少有机溶剂的使用,又得到更高的分析灵敏度。     

牛乳中氨基酚、硝基苯胺和硝基酚残留检测方法研究

本试验采用乙醚作萃取剂,提取牛乳中的氨基酚、硝基苯胺和硝基酚,用高效液相色谱法同时对三种物质进行检测。高效液相色谱条件：固定相为C18反相色谱柱;流动相为0．008mol／LKH2PO4溶液：色谱纯甲醇（60：40）;离子对为四丁基溴化胺（终浓度为0．003mol／L）;柱温25％;紫外检测器检测波长270nm;流速1．0mL/min。结果表明,该方法能够准确地对牛乳中的氨基酚、硝基苯胺和硝基酚进行定性和定量检测。     

反相离子对高效液相色谱法测定饲料中维生素B_1、B_2、烟酸的研究

建立反相离子对高效液相色谱同时测定饲料中维生素B1、B2 和烟酸的方法。色谱柱为μ- Bondapak C(18),流动相含 0.005mol/ L PIC B- 5和 PICB- 7的 25% 甲醇水溶液,用紫外检测器254nm检测,最低检出量2μg,添加回收率为91.68% 、97.08% 、95.81% 。方法简便、灵敏、快速。     

基于双柱固相萃取-色质联用技术同时检测鸡肉中8种抗病毒药物残留

建立了双柱固相萃取-液相色谱-串联质谱法,可实现对鸡肉中金刚烷胺、金刚乙胺、美金刚胺、吗啉胍、利巴韦林、阿昔洛韦、更昔洛韦、奥司他韦等8种抗病毒药物的同时分析。采用三氯乙酸水溶液-乙腈对鸡肉中8种抗病毒药物残留同时提取,依次通过石墨化碳柱和强阳离子交换柱以实现对目标药物的富集、净化,选用石墨化碳色谱柱进行分离,超高效液相色谱-串联质谱检测。本文通过研究不同提取溶液、固相萃取柱及色谱柱对检测结果的影响,最终建立优化的检测方法,采用外标法计算,检测限1μg/kg,定量限2μg/kg,添加浓度在2~200μg/kg范围内的回收率大于80%,适用于鸡肉中8种抗病毒药物的同时分析。     

饲用酸化剂中甲酸、乙酸、丙酸、乳酸、柠檬酸的同步测定

实验建立利用高效液相色谱同时测定饲用酸化剂中甲酸、乙酸、丙酸、乳酸、柠檬酸含量的方法。采用Grom-Sil org acid柱(250 mm×2.1 mm,5μm)进行分析。流动相为pH值2.5磷酸水溶液;流速为1.0 ml/min;检测波长为210 nm;柱温为30℃。在此色谱条件下,5种有机酸分离良好。平均回收率均大于85%,RSD小于10.0%。对实际样品的检测结果表明:该方法操作简便易行,准确可靠。     

蚕药熏烟剂中百菌清含量的分析

介绍了高效液相色谱法测定蚕药熏烟剂中百菌清含量，以C18柱为色谱柱、甲醇和水为流动相的色谱条件分析百菌清的方法，并对方法的线性关系、精密度、准确度、检测限、定量限进行评估。     

迷迭香提取物HPLC特征图谱研究

研究旨在运用高效液相色谱法（HPLC）建立饲用植物迷迭香提取物的特征图谱,为迷迭香提取物的辨别和质量控制提供新的方法。采用Sunfire C18色谱柱,以乙腈-0.1%甲酸水为流动相,以1.0 mL/min的流速、10μL的样品进样量、25℃的柱温、280 nm的紫外吸收波长作为液相色谱条件进行检测。结果显示：试验选取的15批迷迭香提取物色图谱中分离度、峰型较好的8个峰为特征峰,指认了迷迭香酸、鼠尾草酸、鼠尾草酚3个色谱峰,建立了迷迭香提取物的HPLC特征图谱。试验所建立的迷迭香提取物特征图谱实现了对其质量的稳定控制,可为迷迭香提取物质量评价提供参考。     

电感耦合等离子-质谱法测定饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅

应用电感耦合等离子-质谱技术(ICP-MS),建立饲料中钠、镁、铬、锰、铁、铜、锌、砷、硒、镉和铅等元素的测定方法。对饲料样品的前处理方法、仪器工作参数和11种元素标准曲线进行优化;并以加标回收、分析方法比对和重复测试说明方法的准确性和精密性。方法在0～1 000 ng/ml范围内线性良好,仪器检出限为0.557 7～5.072 ng/ml,具有良好的精密度,其回收率在88.1%～104.4%之间,相对标准偏差小于5.0%。同时与原子吸收和原子荧光方法进行比对,测定结果相近。所建立的方法简单、快速,可替代原子吸收和原子荧光方法测定饲料中的11种金属元素,为饲料的质量控制提供理想的元素分析方法。     

Supplementation of broodmares with copper, zinc, iron, manganese, cobalt, iodine, and selenium

In experiment 1, 6 pregnant mares received a concentrate that contained a trace mineral premix that provided 14.3 mg Cu, 40 mg Zn, 28 mg Fe, 28 mg Mn, 0.08 mg Co, 0.16 mg I, and 0.16 mg Se/kg concentrate (group A). Seven mares received the same concentrate plus 502 mg Zn and 127 mg Cu once daily (group B). No differences (P > .05) in foal growth data, or Cu, Zn, and Fe concentrations of mare milk, mare serum, or foal serum were observed. In experiment 2, 6 pregnant mares received the same concentrate as group A (group C), and 8 mares received the same concentrate fortified with 4× the trace mineral premix (group D). Group C mares had higher serum Zn concentration at 1 day (P < 0.01) and 56 days (P < 0.04). Group C mares had higher milk Fe concentration at 28 days (P < .01), and group D mares had higher milk Cu concentration at 56 days (P < .01). Group C foals had higher serum Cu concentration at 14 days (P < .03). The results from this study provide no evidence to indicate that supplementing late gestating and lactating mares with higher dietary trace mineral levels than those recommended currently by NRC has any influence on foal growth and development, or on the Cu, Zn, and Fe concentrations of the mare milk, mare serum, or foal serum.     

Comparisons of Angus, Charolais, Galloway, Hereford, Longhorn, Nellore, Piedmontese, Salers, and Shorthorn breeds for weight, weight adjusted for condition score, height, and condition score of cows

Breed differences for weight (CW), height (CH), and condition score (CS) were estimated from records (n = 12,188) of 2- to 6-yr-old cows (n = 744) from Cycle IV of the U.S. Meat Animal Research Center's Germplasm Evaluation (GPE) Program. Cows were produced from mating Angus and Hereford dams to Angus, Hereford, Charolais, Shorthorn, Galloway, Longhorn, Nellore, Piedmontese, and Salers sires. Samples of Angus and Hereford sires were 1) reference sires born from 1962 through 1970 and 2) 1980s sires born in 1980 through 1987. The mixed model included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breedgroup as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects associated with the cow. Differences among breed groups were significant (P < 0.05) for all traits and were maintained through maturity with few interchanges in ranking. The order of F1 cows for weight was as follows: Charolais (506 to 635 kg for different ages), Shorthorn and Salers, reciprocal Hereford-Angus (HA) with 1980s sires, Nellore, HA with reference sires, Galloway, Piedmontese, and Longhorn (412 to 525 kg for different ages). Order for height was as follows: Nellore (136 to 140 cm), Charolais, Shorthorn, Salers, HA with 1980s sires, Piedmontese, Longhorn, Galloway and HA with reference sires (126 to 128 cm). Hereford and Angus cows with reference sires were generally lighter than those with 1980s sires. In general, breed differences for height followed those for weight except that F1 Nellore cows were tallest, which may in part be due to Bos taurus-Bos indicus heterosis for size.     

液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量的不确定度评估

采用液相色谱-串联质谱法测定动物尿液中11种β-受体激动剂残留量,对标准溶液、体积、质谱峰面积、浓缩过程及回收率等测定不确定度因素进行了分析,通过评定各不确定度分量及标准不确定度,得出11种β-受体激动剂的扩展不确定度在0.7 ～ 1.1 ng/mL范围内.由各因素对合成不确定度的贡献比分析可知,影响较大的因素为试验回收率及标准溶液浓度.     

文山黄牛的现状与保种措施

文章阐述了文山黄牛的品种特性、现状和保种措施。文山牛保种可采用原产地活体保种,迁地活体保种和现代生物技术保种等多种方式。文山牛体型较大,性情温顺,产肉性能好、活动敏捷、结构紧凑、肌肉强健、肉品质优良、耐粗饲、适应性广、繁殖力和抗病力均较强等特点。文山牛是云南省一个地方良种,种质资源保护刻不容缓。