星点东方鲀及共生细菌河鲀毒素的提取与检测

从福建东山县附近海域捕获3尾野生星点东方鲀(Takifugu niphobles),采用液相色谱-串联质谱法检测了其组织及从组织分离到的细菌发酵产物的河鲀毒素(Tetrodotoxin,TTX)含量,结果显示星点东方鲀卵巢、肝脏和肌肉组织的TTX含量分别是56.247、0.380和0.118μg/g。根据16S r DNA测序的结果,从星点东方鲀的肠道中分离到一株鳗利斯顿氏菌属(Listonella sp.)细菌,从肝脏中分离到两种不动杆菌属(Acinetobacter sp.)细菌,从肌肉中分离到一株肠杆菌属(Enterobacter sp.)细菌,从卵巢组织中分离到一株牡蛎弧菌(Vibrio crassostreae),其中,除牡蛎弧菌和一株不动杆菌属细菌外,其他细菌的发酵液提取物中均检测到TTX。这是首次在河鲀鱼类组织中分离到产TTX的鳗利斯顿氏菌属细菌和不动杆菌属细菌。     

环境因子对脱氧雪腐镰刀菌烯醇在小麦中残留降解的影响（英文）

利用三重四级杆液质联用仪LCMSMS研究了环境因子对小麦籽粒中DON毒素的降解影响,不同处理得到的DON毒素降解半衰期范围在54.57~71.44 d,150 d后降解率为78.85%~87.00%,对毒素的降解有加快作用的是自然光强光(10 000 lx)黑暗,90%湿度50%湿度,而高温并不能加快毒素的降解。     

蜂王浆中氯霉素残留量的LC-MS/MS与ELISA检测方法研究

介绍了利用LC-MS/MS与ELISA方法快速、准确地测定蜂王浆中氯霉素残留量.前处理方法包括用酸沉淀蛋白、乙酸乙酯提取、自制硅胶柱、Oasis(HLB)小柱等净化步骤.同时,在LC-MS/MS测定方法中使用了同位素内标氯霉素-d5.建立的LC-MS/MS方法,多反应监测了氯霉素3对离子(321.0/256.9、321.0/194.0、321.0/175.8)和同位素内标氯霉素-d5 1对离子(326.0/157.1),检测低限为0.2μg/kg,线性范围为0.2～0.8μg/kg,加标回收率为97%～102%,RSD为1.9%～7.1%;ELISA方法检测低限为0.1μg/kg,该水平添加回收率为108.2%,RSD为12.2%.     

电喷雾串联质谱法检测氯霉素的初步研究

研究了串联质谱MS／MS分析氯霉素的方法，以国外资料所提供的参数为基础，经过优化和补充建立了一套完整、检测灵敏度更高的质谱仪参数：锥孔电压30V，碰撞电压分别为m／z152，20eV,m/z194,10eV,m/z257,9eV。     

Increased content of phenolic compounds in pear leaves after infection by the pear rust pathogen

European pear rust induced by the fungus Gymnosporangium sabinae (Dicks) G. causes yellow to bright orange leaf spots on leaves of pear trees. The aim of this study is to identify and quantify polyphenolic compounds found in pear leaf extracts. Identified were: ten hydroxycinnamates, eight flavonols, nine flavan-3-ols and three arbutin derivatives. Polymeric procyanidins were additionally determined by UPLC-FL. The total content of phenolics in the control healthy green leaf extract was 11,889.98 mg but in the infected leaves it reached 28,573.89 mg in the samples with yellow spots and 11,480.06 mg/100 g dry matter (dm) in the green part of leaves. The yellow spots in pear rust leaves were characterized by increased content of flavanol (catechins and procyanidins) and arbutin compounds compared with the green part of the infected leaves and control healthy leaves.     

Serum Metabolomics Analysis of Feline Mammary Carcinomas Based on LC-MS Techniques

The purpose of this study was to investigate the variation of differential metabolites in mammary carcinomas bearing cats and healthy cats, and to explore the relationship between differential metabolites and the occurrence of feline mammary carcinomas. In this study, 6 feline mammary carcinomas serum samples were selected as test (T) group. Meanwhile, 6 healthy cats with similar age and same breed were selected as control (C) group. Serum samples were detected by ultra-high performance liquid tandem chromatography quadrupole time of flight mass spectrometry (LC-MS). Differential metabolites were screened by principal component analysis (PCA), orthogonal projections to latent structures-discriminant analysis (OPLS-DA) and Student's t-test. Then the hierarchical clustering analysis (HCA) was carried out for the screened differential metabolites. The KEGG annotation and the metabolic pathway of differential metabolites were analyzed. The results showed that a total of 159 differential metabolites were identified in the 2 groups. Compared with C group, 49 differential metabolites were down-regulated and 110 differential metabolites were up-regulated in T group. Finally, a total of 5 differential metabolites which closely related to feline mammary carcinomas were selected. Ergothioneine (EGT) and creatine in T group were down-regulated, while indolelactic acid (IAA), choline and uric acid were up-regulated compared to C group. These differential metabolites indicated that during the development of feline mammary carcinomas, the body changes involved multiple metabolic pathways, such as glycine, serine and threonine metabolism, arginine and proline metabolism, histidine metabolism, tryptophan metabolism, purine metabolism and glycerophospholipid metabolism. This study provides a new idea for further research of the pathogenesis of feline mammary carcinomas.     

LC-MS/MS方法检测家兔组织中的灰黄霉素

本研究建立了家兔组织中灰黄霉素的高效液相色谱串联质谱(LC-MS/MS)检测方法。将灰黄霉素标准液按一定量加入到肝、肾、肌肉、皮肤及脑组织的匀浆中,以盐酸普萘洛尔为内标,采用二氯甲烷萃取法进行提取,用LC-MS/MS法进行灰黄霉素的组织浓度测定。结果表明,家兔肌肉、肾及肝中灰黄霉素含量的检测线性范围为1.08～249 ng/mL,皮肤、脑组织中灰黄霉素含量的检测线性范围为1.08～51.87 ng/mL;肌肉、肝、肾、皮肤和脑组织中灰黄霉素的定量检测下限为1.08 ng/mL。本研究建立的LC-MS/MS可用于家兔组织中灰黄霉素的检测。     

超高效液相色谱-串联质谱法检测猪血清中泰乐菌素残留的建立

建立一种超高效液相色谱-串联质谱(UPLC-MS/MS)法测定猪血清中泰乐菌素的残留。血清样品在弱酸性条件下,经乙腈溶液提取,Sep-Vac C18固相萃取柱净化,用ACQUITY UPLC BEH-C18色谱柱(50 mm×2.1mm,1.7μm)进行分离,以乙腈-0.2%乙酸作流动相梯度洗脱,经电喷雾正离子模式,多反应监测(MRM)方式质谱分析,外标法定量。泰乐菌素含量在0.5~50 ng.mL-1范围内与峰面积μ呈良好线性,相关系数R2>0.9994,本方法的检测限为0.2 ng·mL-(1S/N>10)。样品添加浓度在5~50 ng·mL-1时,其回收率为73%~84%,日间与日内RSD均小于13.5%(n=5)。建立了一种快速、简单、廉价、高效和严格的方法来检测猪血清中的泰乐菌素残留情况,并为药物代谢动力学研究提供了可靠的检测方法。     

液相色谱-串联质谱法测定鸡蛋中地克珠利的残留量

[目的]用液相色谱-串联质谱法建立鸡蛋中地克珠利残留的检测方法,并考察地克珠利在鸡蛋中的消除规律。[方法]用乙腈和乙酸乙酯的混合溶液提取,60 ℃氮气吹干,乙腈溶解,过0.22 μm微孔滤膜后,采用液相色谱-串联质谱分析。[结果]地克珠利在1-50 μg/kg范围内具有较好的线性关系（r^2〉0.99）,检测限和定量限分别为0.2和0.5 μg/kg。[结论]该方法操作简单、灵敏度高,适用于鸡蛋中地克珠利残留量的检测。     

枯草芽孢杆菌B2菌株产生的抑菌活性物质分析

枯草芽孢杆菌B2菌株产生的胞外物质经盐酸沉淀，甲醇抽提获得粗制备物。利用HPLC系统将粗制备物过Xterra RPl8层析柱分离，共获得120管收集液。以抑制小麦赤霉病菌分生孢子萌发为指标对各管收集液的抑菌活性进行了测定。通过LC-MS分析，结果表明B2菌株胞外存在3种抑菌物质，即脂肽类抗生素表面活性素、多烯类和一种分子量为564的结构未知的新物质。