基于食品安全指数法和危害物风险系数法评估山西省韭菜中农药残留的风险

为评估山西省韭菜中农药残留现状及居民膳食摄入风险，利用GC-MS/MS和UPLC-MS/MS技术对山西省韭菜主产区6个不同地区共计121个待上市韭菜样品中13种农药残留进行了精准定量，进而通过食品安全指数(IFS)法和危害物风险系数法对样品中检出的农药进行风险评估。结果显示，韭菜样品的农药检出率为97.5%，农药残留超标率为32.2%，其中腐霉利是造成韭菜中农药残留超标的主要农药，另检出克百威、毒死蜱、甲拌磷3种禁止在蔬菜上使用的农药，农药多残留检出率为57.0%。韭菜中检出的农药残留种类和数量存在采样时间、种植地区和种植模式上的差异。IFS法评估结果显示，12种检出农药的IFS值均小于1，膳食摄入风险在可接受范围；而危害物风险系数法评估结果表明腐霉利、甲拌磷、毒死蜱、克百威、二甲戊灵和氯氟氰菊酯6种农药为高度风险农药。总之，山西省韭菜质量安全风险仍在可接受范围，但存在高度风险农药使用情况，韭菜质量安全监管工作仍需进一步加强。     

GPC结合超高效液相色谱-串联质谱法测定韭菜中50种农药残留

利用GPC结合超高效液相色谱-串联质谱(UPLC-MS/MS)检测韭菜中50种农药残留。样品用1%乙酸乙腈震荡提取,经凝胶色谱净化,收集9~21min的流出液,在线浓缩近干并用乙腈∶水(1∶3)溶解定容至2ml,收集于2ml样品瓶中,过0.22μm滤膜,以Waters BEHC18色谱柱分离,采用多反应检测模式进行检测,外标法定量。加标水平为0.05mg/kg和0.1mg/kg时,回收率在65.2%~102.1%之间,相对标准偏差小于20%。农药在线性范围内相关系数均大于0.99。方法具有提取效率高,净化效果好,准确度高、灵敏等优点,适用于韭菜中多农药残留检测。     

鲜枣中21种农药气相色谱串联质谱测定及膳食风险评估

利用气相色谱串联质谱法（GC-MS/MS）检测结合QuEChERS前处理方法建立了鲜枣中21种农药残留分析方法，回收率和精密度均满足农药残留分析要求，定量限为5～20μg/kg。通过测定145个鲜枣样品中21种目标农药的残留水平，发现36%鲜枣样品中存在较低水平的农药残留检出。通过膳食风险评估（%ADI）发现，鲜枣样品中残留农药%ADI在12.9%以下，远低于100%，表明鲜枣中目标农药残留膳食摄入风险在可接受范围之内。     

超高效液相色谱-串联质谱检测蔬菜中氨基甲酸酯类农药残留

以番茄、茄子、西葫芦、大白菜、甘蓝为试材,采用超高效液相色谱-串联质谱(UPLC-MS/MS)技术建立了蔬菜中12种氨基甲酸酯类农药残留的检测方法。结果表明:样品经乙腈提取,氨基固相萃取小柱净化,以waters BEH T3色谱柱分离,采用多反应检测模式对试材进行检测,外标法定量;在质量浓度1~100μg/L范围内呈良好线性,相关系数均大于0.99。在空白基质中添加3个水平加标试验,回收率为65.2%~119.2%,相对标准偏差均小于5%。该方法灵敏度高、准确可靠、精密度好、选择性强,可以满足蔬菜中氨基甲酸酯类农药残留检测的要求。     

综合安全评估（FSA）法在芹菜农药残留安全评估中的应用

采用GC-MS/MS和LC-MS/MS方法,对18份芹菜样品中的179种农药残留进行检测;综合考虑农药残留的LD_(50)、ADI、芹菜摄入量占总膳食比例、农药使用频率、是否存在高暴露人群和检测中值等主要影响因素,运用综合安全评估(FSA)方法,通过3种赋值方式计算不同农药残留的风险总分并排序。结果表明:特丁硫磷、水胺硫磷、喹硫磷、地虫硫磷在芹菜中的安全风险相对较高。同时分析了FSA方法进行芹菜农药残留安全评估的优点和不足。     

阿维菌素在柑桔和土壤中的残留及其消解动态

为了解柑桔果实和土壤中阿维菌素的残留消解规律和明确阿维菌素的安全间隔期,建立液相色谱-串联质谱法(LC-MS/MS)结合QuEChERS样品前处理方法,对重庆北碚和湖南张家界两地田间施药[33%联苯肼酯·阿维菌素悬浮剂(3%阿维菌素)]后柑桔果实和土壤中阿维菌素的残留情况进行研究。结果表明,检测方法的准确度和精密度均符合农药残留试验准则的要求,对阿维菌素的最低检测浓度为0.005mg/kg。阿维菌素残留量随时间的延长而降低,消解动态曲线符合一级动力学指数模型,在柑桔果实和土壤中的半衰期分别为5.0~10.7d和8.8~10.0d,属于易降解农药。建议33%联苯肼酯·阿维菌素悬浮剂的使用浓度为3 000倍液,最多连续施药2次(间隔7d),食用安全间隔期为30d。     

赣州地区脐橙农药残留及其分布特征

为揭示江西赣州地区脐橙中农药残留现状及其地理分布特征,2014年11月在江西赣州18个区县的110个乡镇共采集788份脐橙鲜果样品,采用QuEChERS技术结合GC/MS-MS和HPLC-MS/MS测定样品果肉中166种农药残留,并随机抽取25份样品对比分析果肉和果皮的农药残留。结果表明:(1)样品果肉中共检出18种农药,其中,啶虫脒、多菌灵、咪鲜胺、杀扑磷、甲基硫菌灵、氧乐果等检出率较高;(2)寻乌、龙南、赣县和石城的样品中农药检出率很高,阳性样品达到60%以上,兴国和上犹的检出率很低;(3)果肉和果皮的农药残留状况存在差异;(4)赣州脐橙整体比较安全,仅有7份样品的果肉出现农药(氧乐果)残留量超过国家标准(GB 2763—2014)的限量要求,占检测样品总数的0.89%。     

溴氰虫酰胺和吡蚜酮在南瓜中的残留消解动态

建立了用于检测南瓜中溴氰虫酰胺、吡蚜酮残留的分析方法,并对河北、浙江两地的溴氰虫酰胺 · 吡蚜酮水分散粒剂在南瓜中的消解动态规律和最终残留进行了研究.样品经乙腈提取,N-丙基乙二胺(PSA)净化后,采用液相色谱-串联质谱仪测定.结果表明,南瓜样品中溴氰虫酰胺和吡蚜酮的最低检出浓度分别为0.01 mg·kg-1和0.00...     

氟啶胺在小白菜中的残留行为及膳食摄入风险评估

为了建立一种由超高效液相色谱-串联质谱(UPLC-MS/MS)检测小白菜中氟啶胺的分析方法,并对小白菜中的残留量进行膳食风险评估。样品经乙腈提取,NaCl盐析、无水MgSO₄、N-丙基乙二胺(PSA)和石墨化碳黑(GCB)净化,超高效液相色谱-串联质谱检测。结果表明,小白菜中氟啶胺的标准曲线为y=2 000 000 x+15 687,R²=0.992 8,平均回收率为105%～108%,相对标准偏差为1%～7%,在0.005～0.500 mg·kg^-1范围内具有良好的线性关系,方法正确度和精密度均符合农作物中农药残留试验准则要求。氟啶胺的普通人群每日摄入量国家估算值为0.12 mg,占允许摄入量的19.5%,不会对一般人群构成不可接受的风险。     

蔬菜农药残留检测中基质效应影响因素分析

为了提高农药检测的准确率,试验选择气相色谱(7890A、1310)与气相串联质谱(GCMS-MS)3种不同仪器,结球白菜、结球甘蓝、黄瓜、辣椒4种蔬菜样品及其基质标准溶液和正己烷溶剂标准溶液,对4种不同蔬菜中分别添加腐霉利、甲氰菊酯、氯氰菊酯、溴氰菊酯4种农药并进行回收校正,比较不同的校正溶液、不同仪器以及不同的样品类型对蔬菜农药残留检测中的基质效应的影响。结果显示:按不同基质标准溶液和溶剂标准溶液校正的检测结果分类,不同蔬菜、不同的标准校正溶液对于农药残留检测中的基质效应表现出多样性和复杂性的特点。但采用与本底一致的基质标准溶液校正样品可有效消除基质效应。按不同仪器检测结果分类,气相色谱(7890A、1310)与气相串联质谱(GC-MS-MS)基质效应的影响存在一定的差异,GC-MS-MS存在较为明显的基质增强效应;而同类仪器(7890A、1310)之间基质效应的影响较小。     

应用iTRAQ结合2D LC-MS/MS技术分析草菇同核和异核菌丝蛋白质组

首次利用同位素标记相对和绝对定量(isobaric tags for relative and absolute quantification,iTRAQ)技术结合二维液相色谱串联质谱对草菇(Volvariella volvacea)同核和异核菌丝蛋白质组进行研究。采用QExactive质谱鉴定并经MASCOT软件搜库,对所有鉴定蛋白进行主成分分析(principal component analysis,PCA)、层次聚类(hierarchical clustering)分析和GO(gene ontology)注释,并进行生物信息学分析。结果共获得2335个不同肽段,鉴定到1039个蛋白,其中1030个蛋白具有定量信息。在同核菌丝中显著上调蛋白83个,下调蛋白97个,表明iTRAQ标记技术结合二维液相色谱串联质谱可有效地分离和鉴定草菇菌丝蛋白质组。该研究结果为更深入全面地研究草菇菌丝蛋白质组学奠定基础。     

快速测定豇豆中农药残留量的方法研究

建立豇豆中克百威、三羟基克百威、残杀威、灭多威、抗蚜威、仲丁威、甲萘威、异丙威、速灭威9种农药残留的超高效液相色谱-串联质谱(UPLC-MS/MS)测定方法。样品通过乙腈匀浆提取,在电喷电离方式(ESI+)、多反应监测模式(MRM)下进行测定,基质配标准曲线定量。分析物在0.01～0.50 mg/L范围内呈线性,相关系数r0.99,空白样品中分析物在0.01 mg/kg、0.02 mg/kg、0.10 mg/kg 3个不同添加水平时,平均回收率在89.0%～110.0%之间;相对标准偏差为0.7%～9.1%,定量限为0.005～0.01 mg/kg,满足定量分析的要求。     

Identification of specific serum biomarkers in gastric adenocarcinoma patients

AIM: To screen the possible serum biomarkers for the diagnosis of gastric adenocarcinoma. METHODS: The surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS) was used to screen the serum samples from 109 cases of gastric adenocarcinoma and 106 control subjects (60 healthy subjects, 30 patients with chronic superficial gastritis and 16 cases of chronic atrophic gastritis). The differentially-expressed protein peaks were selected and isolated with high-performance liquid chromatography (HPLC), and processed with enzyme before liquid chromatography-mass spectrometry tandem mass spectrometry (LC-MS/MS) analysis. The data mining was performed with software Xcalibur program component Bioworks 3.2. RESULTS: Three differentially-expressed protein peaks were selected as potential serum biomarkers of gastric adenocarcinoma patients.The m/z peak at 5 906.5 showed the increase (8.53±4.33 in cancer group, and 0.88±0.31 in control group). The m/z peaks at 6 635.7 and 8 716.3 showed the decrease (6.54±2.44 and 0.93 ± 0.29, respectively, in cancer group and 17.56±4.43 and 2.16±0.98, respectively, in control group, P<0.01). The 3 m/z peaks were identified as fibrinogen α-chain, apolipoprotein A-II and apolipoprotein CI,respectively. The combined use of the 3 biomarkers distinguished the samples in the cancer patients out of the controls at a sensitivity of 93.85% (61/65) and a specificity of 94.34% (50/53). CONCLUSION: The fibrinogen α-chain, apolipoprotein A-II and apolipoprotein CI identified as potential markers for gastric adenocarcinoma show diagnostic values in clinical application.     

甜椒中螺虫乙酯主要代谢产物及残留量膳食摄入评估

为了研究甜椒中螺虫乙酯主要代谢物的转化情况、施药措施与残留量的相关性,以及残留量膳食摄入评估,利用建立的螺虫乙酯及其4个主要代谢物的高效液相色谱三重四极杆串联质谱法,对施用过螺虫乙酯的甜椒样品进行检测分析及膳食摄入评估.结果表明,甜椒中螺虫乙酯及其4个主要代谢物的平均回收率为89％～107％,相对标准偏差为1.2％～4...     

独山盐酸菜风味物质的研究

采用水蒸气蒸馏法、气相色谱和质谱联用技术(GC/MS),共鉴定出贵州传统食品独山盐酸菜2个样品中的挥发性化合物11类28种,包括酯、酸、酰胺、醇、醛、酚、烯、苯、酮、噻唑、盐等。其中酸、醛、酯是主体挥发物,对产品风味的形成起重要作用。     

广叶绣球菌子实体不同发育阶段的比较蛋白质组学分析

利用同位素标记相对和绝对定量(isobaric tags for relative and absolute quantification,iTRAQ)标记结合二维液相色谱串联质谱(two-dimensional liquid chromatography tandem mass spectrometry,2D LC-MS/MS)技术,研究广叶绣球菌(Sparassis latifolia)原基期、幼菇期和成熟子实体阶段的差异表达蛋白质组.采用Q-Exactive质谱鉴定并经ProteinPilot软件搜库,对所获得的差异蛋白进行GO (gene ontology)、KEGG(kyoto encyclopedia of genes and genomes)和转录因子注释分析.结果共鉴定到可信蛋白2305个,其中2219个蛋白具有相对定量信息.与原基期相比,幼菇期显著上调蛋白104个,下调蛋白142个,子实体阶段显著上调蛋白155个,下调蛋白460个.GO分子功能提示这些差异性蛋白主要参与催化活性、蛋白结合和水解酶活性.KEGG代谢通路分析结果显示,差异蛋白主要涉及碳代谢、氨基酸合成、核糖体、糖酵解/糖衍生等代谢过程.差异蛋白中与信号传导和转录因子相关的蛋白数量分别为27个和7个.     

广叶绣球菌溶血素基因的序列分析及表达动态

通过转录组测序获得了一个广叶绣球菌(Sparassis latifolia)编码的溶血素基因(latifolysin),进行生物信息学分析,并利用实时定量PCR分析溶血素基因表达水平,采用同位素标记相对和绝对定量(isobaric tags for relative and absolute quantification,iTRAQ)标记结合二维液相色谱串联质谱鉴定分析溶血素表达差异.结果表明latifolysin基因全长为399 bp,编码133个氨基酸.保守功能域搜索显示latifolysin具有与杨树菇溶血素(aegerolysins)蛋白家族相同的结构域和功能位点,两者序列相似性40％.杨树菇溶血素家族蛋白在真菌中呈不连续性分布.系统进化树结果显示绣球菌溶血素隶属于担子菌类群,与草菇(Volvariellavolvacea)遗传关系较近.实时定量PCR和蛋白定量结果表明,latifolysin和绣球菌溶血素在广叶绣球菌幼菇期表达量最高,且显著高于菌丝体中表达水平.     

Screening and identification of specific serum biomarkers of Parkinson disease

AIM：To screen the possible serum biomarkers of Parkinson’s disease. METHODS：The surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS) was used to screen the serum samples from 44 cases of Parkinson’s disease and 60 control subjects. The differentially expressed protein peaks were selected and isolated with high-performance liquid chromatography (HPLC), and processed with enzyme before analysis by liquid chromatography-mass spectrometry tandem mass spectrometry (LC-MS/MS). The data mining was performed by Xcalibur program component BioWorks 3.2. RESULTS：Three differentially expressed protein peaks were selected as potential serum biomarkers from the patients of Parkinson’s disease: the protein at 8 937 m/z peak showed significant increase (27.47±16.58 in Parkinson’s disease group, and only 5.01±3.47 in control group), and the proteins at 6 636 and 8 697 m/z peaks showed significant decreases (5.43±2.66 and 20.22±9.57, respectively, in Parkinson’s disease group, and 18.85±7.56 and 51.13±26.22, respectively, in control group). The proteins at 6 636, 8 697 and 8 937 m/z peaks were identified as apolipoprotein C-I, apolipoprotein C-III and complement 3a,respectively. Combined use of these 3 biomarkers effectively distinguished the subjects between Parkinsons disease group and control group. The detection rate of the patients with Parkinsons disease was 90.0% (27/30), and the detection rate of the healthy sibkects was 92.5% (37/40). CONCLUSION：The apolipoprotein C-I, apolipoprotein C-III and complement component 3a identified as potential markers of Parkinson’s disease have diagnostic value in clinical application.     

Effect of somatostatin analogue octreotide on metabolism of LPS-induced A549 cells

AIM: To investigate the effects of octreotide on metabolism in the A549 cells treated with lipopolysaccharides (LPS). METHODS: The technologies of gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS) were used to test the metabolism of lung A549 cells subject to different treatment with LPS and/or octreotide. The results were visualized and checked by chromatogram, and the corresponding intensity data were analyzed by the principal component analysis(PCA)method. The metabolites with different expression and the underlying interaction network were resolved. RESULTS: The metabolism analysis by LC/MS method indicated that there were different expression levels between different treated groups. Further analysis was carried out by orthogonal projections to latent structures-discriminant analysis (OPLS-DA) and the different expressed metabolites were obtained, which were mainly amino acids and phospholipids. By analyzing with GC/MS method and t-test, the different expressed metabolites were mainly organic acid, saccharides and amino acid metabolite. The interaction network diagram was constructed about the response of A549 cells induced by LPS and/or octreotide, including glycolysis/gluconenogenesis, tryptophan metabolism, galactose metabolism, urine cycle and citrate cycle. Fourteen key components were found such as serotonin, indole, threonine, serine, glucose, phenylalanine, lactose, fumarate, 4-hydroxyphenyllactate, aspartate, asparagine, putrescine, proline and succinate. CONCLUSION: In octreotide treated LPS-induced A549 cells, the main metabolites are organic acid, saccharides, amino acids and phospholipids. The interaction network is constructed, including 5 metabolic pathways and 14 key components.