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1.
QuEChERS_GPC_GC_MS快速测定蔬菜中24种农药残留 总被引：1，自引：0，他引：1
采用QuEChERS前处理方法和在线凝胶渗透色谱-气相色谱质谱联用仪(gel permeation chromatography-gas chromatography/mass spectrometry,GPC-GC/MS)快速测定蔬菜中24种多农药残留。样品经乙腈提取,净化采用分散固相萃取的方式,加标浓度为0.1 mg/kg,油麦菜样品中的24种农药回收率大部分在70%～120%,24种农药的检出限范围在0.000 2～0.009 mg/kg,线性范围0.025～0.30 mg/L,相对标准偏差在1.41%～10.05%,满足农药多残留的分析要求。实验表明,QuEChERS方法提取和净化使样品前处理更为简单、方便、快速,GPC-GC/MS系统中的GPC柱弥补了QuEChERS方法去除干扰物不彻底的问题,能更准确地检测出蔬菜中多农药残留,检测灵敏度高,重现性好。 相似文献
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建立了超高效液相色谱-串联质谱法测定茶叶中灭草松及其代谢产物的快速检测方法。茶叶样品使用0.1%冰乙酸-甲醇混合溶液提取，上清液使用石墨化碳黑(GCB)、N-丙基乙二胺(PSA)、Mg SO4组成的复合填料净化过滤后，经超高效液相色谱-串联质谱法测定，最后通过外标法定量。结果表明，在试验条件下，灭草松在0.001～0.010 mg/L含量范围内具有较好的线性关系，其代谢产物在0.000 2～0.002 0 mg/L含量范围内同样具有较好的线性关系，相关系数(R2)均大于0.995；本方法对灭草松的定量限为0.01 mg/kg，对两种代谢产物的定量限均为0.002 mg/kg。该方法操作简单、快捷、灵敏、精密度高、成本低，能够满足茶叶中灭草松及代谢物的检测需求。 相似文献
3.
建立分散固相萃取-反相高效液相色谱同时测定蔬菜和水果中10种氨基甲酸酯类农药(涕灭威，涕灭威砜，涕灭威亚砜，克百威，3-羟基克百威，灭多威，甲萘威，异丙威，速灭威，仲丁威)残留的分析方法。样品经乙腈提取，PSA分散固相萃取净化，液相色谱柱后衍生分离，荧光检测(λex＝330 nm, λem＝465 nm)测定，外标法定量。10种农药在0.005～0.50 mg/L范围内线性关系良好；检出限在0.004～0.008 mg/L；平均加标回收率在75.6%～112.3%，相对标准偏差(RSD)在 0.8%～10.2%。该方法具有快速、灵敏、准确、重现性好以及操作简单等特点，适合日常大批量蔬菜和水果样品中10种氨基甲酸酯类农药残留的测定。 相似文献
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建立以超高效液相色谱-串联质谱(UPLC-MS/MS)同时测定茶鲜叶中79种农药残留量的分析方法。以乙腈为提取剂，茶鲜叶样品经高速破壁均质后加入NaCl盐析，离心取上清液经无水硫酸镁、C18、PSA和GCB分散固相萃取净化后上机，多反应监测模式扫描，分段时间窗口采集数据，外标法定量。结果显示，79种目标化合物在0.001～0.400 mg·L-1质量浓度范围内线性良好，相关系数(R2)为0.990 6～0.999 9，在0.01、0.03、0.05、0.10 mg·kg-1和0.20 mg·kg-1等5个添加水平下的平均回收率为70.7%～119.0%，相对标准偏差(RSD)为0.1%～19.8%，方法定量限为0.01～0.05 mg·kg-1。该方法灵敏度高、准确性好、分析速度快，适用于茶鲜叶中79种农药残留的检测。 相似文献
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建立了采用固相萃取-超高效液相色谱-质谱/质谱法(SPE-LC-MS/MS)对叶菜中11种氨基甲酸酯农药(克百威、3羟基克百威、甲萘威、仲丁威、异丙威、抗牙威、速灭威、灭多威、涕灭威、涕灭威亚砜、涕灭威砜)残留同时测定的方法。样品用乙腈提取后经氨基固相萃取柱净化处理,经Acquity UPLCTM BEH C18(100 mm×2.1 mm,1.7 μm)色谱柱分离后测定,该方法采用多反应监测(MRM)离子扫描模式,外标法进行定量,线性良好(r2＞0.994),检出限为0.001～0.004 mg/kg,总体回收率为80.4%～99.8%,相对标准偏差为3.4%～10.8%。该方法的定量限满足目前国内外药物的最大残留限量要求,可作为叶菜中相关药物残留的筛选检测方法。 相似文献
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运用在线凝胶色谱-气相色谱质谱联用(GPC-GC/MS)技术,建立一种快速、准确测定菠菜样品中55种农药残留的方法。样品用乙腈提取,经盐析、PSA净化后,使用GPC-GC/MS进行检测。结果表明：各组分分离良好,在0.025、0.05及0.10 mg/kg 3个添加水平,55种农药的回收率在81.3%～106.2%,相对标准偏差均低于10.3%;在0.01～0.5 μg/mL浓度范围内,线性关系良好,相关系数均大于0.995 3;55种农药的检出限为0.005～0.5 μg/kg。该方法准确、灵敏、快速,可满足对菠菜中55种农药残留的检测需要。 相似文献
8.
《福建热作科技》2021,(3)
建立了基于QuEChERS(快速Quick、简单Easy、廉价Cheap、有效Effective、耐用Rugged、安全Safe)前处理技术和高效液相色谱-串联质谱法同时测定柑橘中13种磺酰脲类除草剂的分析方法。通过对提取溶剂、净化剂、色谱条件、质谱条件等进行优化,确定样品用乙腈提取,经QuEChERS方法净化后,以0.1%甲酸水溶液和甲醇作为流动相,用Hypersil GOLD C18色谱柱(1.9μm 2.1mm×100mm)进行梯度洗脱分离,在高效液相色谱-电喷雾串联质谱仪正离子扫描多反应监测模式下测定,外标法定量。结果表明,13种目标物在1.0～100.0 ng/mL的范围内线性关系良好,相关系数(r)均不低于0.9960。在5.0、20.0、50.0μg/kg添加水平下的回收率为65.4%～110.0%,相对标准偏差(n=5)为3.7%～9.8%,检出限(以信噪比大于3计)为0.02～0.30μg/kg,定量限(以信噪比大于10计)为0.07～0.98μg/kg。该方法稳定可靠,灵敏度高,适用于柑橘中13种磺酰脲类除草剂残留的同时检测。 相似文献
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为准确测定反式维生素K1的含量，建立了基于固相萃取-高效液相色谱串联质谱的甘蓝型油菜（Brassica napus L.）菜薹反式维生素K1高灵敏检测技术。样品经正己烷提取、中性氧化铝柱净化后，用C30反相色谱柱，以甲醇 （含0.025%甲酸+2.5 mmol/L甲酸铵）为流动相，采用选择反应监测（selected reaction monitoring, SRM）模式进行定量分析，20 min内可实现顺反异构体色谱分离。方法学考察结果显示，反式维生素K1在范围内线性关系良好，相关系数为0.9985。该方法检出限为0.29 μg/kg，定量限为0.95 μg/kg。回收率为87.5%～117.6%，精密度（RSD）在0.72% ～9.59%之间。利用该方法对油菜薹和反式维生素K1含量高的3种蔬菜进行分析，发现油菜薹中反式维生素K1含量为340.08 μg/100g，高于小白菜（B. rapa spp. chinensis，260.93 μg/100g）、西兰花（B. oleracea var. Italic Planch， 167.65 μg/100g）和结球甘蓝（B. oleracea var. capitata，151.11 μg/100g）。本文建立的蔬菜中反式维生素K1准确定量分析方法操作简单、灵敏度高、结果准确。同时比较发现油菜薹是一种富含维生素K1的蔬菜。 相似文献
10.
多壁碳纳米管分散固相萃取气相色谱-质谱法测定红甜菜中10种农药残留 总被引：1，自引：0，他引：1
《中国糖料》2019,(3)
以多壁碳纳米管分散固相萃取作为前处理手段,气相色谱-质谱法进行检测,建立了红甜菜中10种农药残留的测定方法。样品经乙腈提取,多壁碳纳米管、PSA、MgSO4分散固相萃取去除杂质,选择离子监测模式,外标法定量,对甜菜中10种农药残留进行了联合测定。结果表明:10种农药的浓度线性范围在10(或者30)μg/L～0.5 mg/L之间,相关系数(R2)均大于0.99。10种农药的平均回收率在73.8%～99.2%之间,相对标准偏差为2.3%～8.25%,最低检出限为1～9μg/kg。此方法简便、快速且具有较高的灵敏度,符合农药多残留分析的要求。 相似文献
11.
Joseph E. Laferriere Charles W. Weber Edwin A. Kohlhepp 《Plant foods for human nutrition (Dordrecht, Netherlands)》1991,41(3):277-282
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described. 相似文献
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Lakshman Lal 《Potato Research》1987,30(2):329-334
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong
(1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage,
sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over
45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield
of a subsequent crop. 相似文献
14.
《Journal of Crop Improvement》2013,27(2):81-114
Summary The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices. 相似文献
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Tatiana G. Polotow Sandra C. Poppe Cristina V. Vardaris Douglas Ganini Maísa Guariroba Rita Mattei Elaine Hatanaka Maria F. Martins Eduardo F. Bondan Marcelo P. Barros 《Marine drugs》2015,13(10):6117-6137
Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions. 相似文献
17.
Youna Hemery Ulla Holopainen Anna-Maija Lampi Pekka Lehtinen Tanja Nurmi Vieno Piironen Minnamari Edelmann Xavier Rouau 《Journal of Cereal Science》2011
Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased. 相似文献
18.
M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results
for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin
presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear
relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins
and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds. 相似文献
19.
Alexander N. Shikov Elena V. Flisyuk Ekaterina D. Obluchinskaya Olga N. Pozharitskaya 《Marine drugs》2020,18(11)
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future. 相似文献
20.
Novel food and non-food uses for sorghum and millets 总被引：4，自引：3，他引：4
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity. 相似文献