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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   

2.
采用高效液相色谱技术,以草莓、西瓜和西红柿为研究对象,建立了一种快速、准确测定蔬菜、水果中烯酰吗啉与赤霉素残留测定方法。酸性条件下(pH 2.5),样品用乙酸乙酯提取,经弗罗里硅土柱净化后,使用配有紫外检测器的高效液相色谱仪进行检测。结果表明,各组分分离良好,在0.025、0.050、0.100 mg/kg这3个添加水平,2种农药的回收率为81.2%~91.3%,相对标准偏差均小于6.7%;在0.025~1.00 μg/mL浓度范围内,线性关系良好,相关系数均大于0.9995;烯酰吗啉与赤霉素的检出限分别为为0.01、0.02 mg/kg。该方法准确、灵敏、快速,可满足对蔬菜、水果中烯酰吗啉与赤霉素农药残留的检测需要。  相似文献   

3.
建立槟榔中9种有机磷农药残留的三重四级杆液相色谱-质谱联用分析方法,采用1%乙酸-乙腈溶液作为提取液,直接稀释后以液相色谱-串联质谱仪在多反应监测模式(MRM)下检测。研究结果发现,9种有机磷农药成分的线性范围均在2~20 ng/mL,相关系数r均大于0.999。方法的平均回收率在73.4%~120%,RSD为0.59%~9.93%,方法检出限为50.0 μg/kg。此方法具有良好的回收率及稳定性,可用于槟榔中有机磷农药残留的测定。  相似文献   

4.
建立在线凝胶渗透色谱-气相质谱分析小麦粉中50种农药残留的方法。样品经乙腈超声提取,提取液经GPC-GCMS在线净化、分离和检测,方法的加标回收率为73.06%~119.9%,相对标准偏差为0.88%~11.02%。方法的检出限为0.000 3~0.009 mg/kg,该方法样品前处理简单、快速、灵敏度高、重现性好,能够满足农药多残留检测技术的要求。  相似文献   

5.
为建立同时测定蔬菜中阿维菌素和氟吡菌酰胺残留的超高效液相色谱-串联质谱(UPLC-MS/MS)方法,采用乙腈高速匀浆提取蔬菜样品中的阿维菌素和氟吡菌酰胺,利用无水硫酸镁和PSA吸附剂进行净化,在UPLC-MS/MS的正离子电离和多反应离子监测模式下进行测定。结果表明,阿维菌素和氟吡菌酰胺的检出限分别为1.0、0.2 μg/kg;在0.005~0.200 mg/L浓度范围内,其线性相关系数均大于0.999。阿维菌素和氟吡菌酰胺在3个试验水平(0.01、0.02和1.0 mg/kg)的添加回收率分别为83%~106%和90%~108%,相对标准偏差分别在0.5%~5.2%和1.2%~8.4%。本方法前处理过程快速简单,仪器分析灵敏度好,方法准确度高,可用于蔬菜样品中阿维菌素和氟吡菌酰胺农药残留量的检测分析。  相似文献   

6.
为了测定植物生长调节剂在香蕉中的残留,本研究建立了 QuEChERS 结合超高效液相色谱-串联质谱法同时测定香蕉中8种植物生长调节剂残留的分析方法。以1%乙酸-乙腈(V/V)为提取溶剂,样品前处理采用 QuEChERS 方法。以Agilent InfinityLab Poroshell 120 EC-C18柱为分离色谱柱,甲醇和5 mmol/L 乙酸铵-0.1%甲酸缓冲溶液为流动相,0.25 mL/min的流速梯度洗脱,10 min内可实现8种目标待测物分离。8种目标待测物经超高效液相色谱-串联质谱在选择反应监测模式下测定,基质匹配标准溶液外标法定量。结果表明,在5.0~100.0 μg/kg范围内线性良好,相关系数(r2)≥0.999;检出限(LODs)范围为0.03~0.6 μg/kg,定量限范围为0.10~2.0 μg/kg。在10、20、100 μg/kg 3个添加水平范围内,平均回收率在73.5%~107.2%之间,相对标准偏差(RSD)小于11%。本方法简便、快速、便捷、灵敏、准确,适用于香蕉中8种植物生长调节剂残留的测定。本方法的建立可为植物生长调节剂在其他果蔬中的残留检测提供参考。  相似文献   

7.
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   

8.
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   

9.
为建立超高效液相色谱-质谱/质谱法(UPLC-MS/MS)同时测定蔬菜中7种磺胺残留量的方法。样品用1%乙酸乙腈提取,以C18色谱柱分离待测物,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,相关系数均大于0.999。结果显示:7种磺胺的检出限为0.000 4~0.000 6 mg/kg,样品添加回收率为67.5%~94.1%,相对标准偏差均少于5.3%(n=6)。该方法简单快捷、定量准确,可满足多种蔬菜中7种磺胺的残留检测要求。  相似文献   

10.
八氯二丙醚(S-421)被广泛地作为农药增效剂。在农药、蚊香中使用,使其在茶叶中也有一定的残留。与已有的标准方法SN/T 1774-2006对比,是一种简便、快速测定茶叶中八氯二丙醚农药残留的方法。利用气相色谱-串联质谱(GC-MS/MS)检测技术,采用QuEChERS法作为样品前处理方法。通过保留时间、选择离子及其相对丰度定性,外标法定量。结果表明,八氯二丙醚的线性范围为0.006-0.06 μg/mL,线性相关系数0.999,加标回收率为83 %-92 %,相对标准偏差小于10 %。 该方法的检出限为0.001 mg/kg。  相似文献   

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   

12.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

13.
The review of the 2016–2017 marine pharmacology literature was prepared in a manner similar as the 10 prior reviews of this series. Preclinical marine pharmacology research during 2016–2017 assessed 313 marine compounds with novel pharmacology reported by a growing number of investigators from 54 countries. The peer-reviewed literature reported antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral activities for 123 marine natural products, 111 marine compounds with antidiabetic and anti-inflammatory activities as well as affecting the immune and nervous system, while in contrast 79 marine compounds displayed miscellaneous mechanisms of action which upon further investigation may contribute to several pharmacological classes. Therefore, in 2016–2017, the preclinical marine natural product pharmacology pipeline generated both novel pharmacology as well as potentially new lead compounds for the growing clinical marine pharmaceutical pipeline, and thus sustained with its contributions the global research for novel and effective therapeutic strategies for multiple disease categories.  相似文献   

14.
SUMMARY

Vitamin A, iodine, and iron deficiencies affect large numbers of people worldwide. A deficiency of one or more of these micronutrients adversely affects the physical and mental abilities of humans. South Asia contains a high percentage of these individuals, not just because of its large population, but also the prevalence of deficiency is higher there than in many other parts of the world. The reasons for the high rates of deficiency in South Asia are many, but they include inadequate availability of micronutrient-rich foods, sub-optimal dietary habits, and high rates of infection. Across the region, national plans vary from (a) increasing availability of appropriate foods, (b) introducing new dietary behaviors, (c) improving health status, and (d) directly addressing deficiency through intervention programs. The extent to which each of the countries is making progress toward the goals of these plans can help in understanding the priorities for future efforts to address micronutrient malnutrition. This article discusses the adverse effects of micronutrient deficiencies in humans with special reference to South Asia.  相似文献   

15.
Summary

Within the last three decades, the rice-wheat cropping system has triggered, and with time, aggravated soil micronutrient deficiencies in the Indo-Gangetic Plains (IGP). This has largely been due to the shift from an earlier rice and wheat monoculture with low yielding, long duration indigenous varieties, to an intensive rice-wheat rotation cropping system with short duration modern high yielding varieties on the same piece of land. The problems related to micronutrient deficiency in the IGP are more due to the size of its available pools in the soil rather than its total contents and are greatly influenced by crop management, or rather its mismanagement. Deficiency of zinc is widespread in the IGP, but with the extensive use of zinc sulfate, zinc deficiency has reduced in some areas of the region. Meanwhile, the deficiency of Fe, Mn and B has increased in the IGP. Deficiency of Cu and Mo is location specific and can limit rice and wheat yields. The adoption and spread of the rice-wheat system in permeable coarse textured soils, particularly in the western IGP, not only caused iron deficiency in rice but also resulted in the emergence of manganese deficiency in wheat. In highly calcareous and acidic soils, boron is the next limiting micronutrient in crop production after zinc. Bumper rice and wheat harvests in the past decade, the declining use of organic manures in the region and except for the widespread use of zinc sulfate, a general lack of awareness amongst farmers on micronutrient deficiency problems has contributed to micronutrients limiting rice and wheat yields in the IGP. Approaches to alleviating micronutrient deficiencies include matching the crop removals of the micronutrients with its replenishments through their respective external carriers, supplementation through organic sources and mobilization/utilization through cultivation of micronutrient efficient crop cultivars. Identification of efficient micronutrient carriers and finding the optimum rate, mode and time of its application is important in ameliorating the micronutrient deficiencies. This article reviews the extent of micronutrient deficiency and discusses various management options available to reduce micronutrient deficiency induced crop yield reduction for rice and wheat in the Indo-Gangetic Plains.  相似文献   

16.
Plains rough fescue ( F estuca hallii) is an important forage grass species in western Canada. Seed for use in pastures and ecological restoration is in high demand but supply is limited because F. hallii is an erratic seed producer. Seed producers require an understanding of the factors that influence flowering and seed set in this species. The aim of this study was to assess the effect of irrigation and nitrogen fertilization on the flowering and growth of F. hallii in a native rough fescue prairie in Alberta, Canada. Irrigation had a strong positive effect on seedhead density, whereas fertilization had limited effects on growth and reproduction of F. hallii. These results demonstrate that under field conditions, available moisture is likely to be a key factor driving flowering and seed production in F. hallii.  相似文献   

17.
Marine biomass diversity is a tremendous source of potential anticancer compounds. Several natural marine products have been described to restore tumor cell sensitivity to TNF-related apoptosis inducing ligand (TRAIL)-induced cell death. TRAIL is involved during tumor immune surveillance. Its selectivity for cancer cells has attracted much attention in oncology. This review aims at discussing the main mechanisms by which TRAIL signaling is regulated and presenting how marine bioactive compounds have been found, so far, to overcome TRAIL resistance in tumor cells.  相似文献   

18.
Summary Morphological and biochemical parameters that could be involved in resistance to late blight were studied in non-infected and in infected potato hybrids resulting from a cross betweenSolanum phureja, resistant toPhytophthora infestans, and a susceptibleSolanum tuberosum. Some morphological differences between resistant and susceptible hybrids, indicating a positive correlation between stem diameter and phloem thickness in the stem and resistance toP. infestans, were observed. The lignin content in the leaves of the resistant hybrid rose upon infection byP. infestans. In the leaves of the susceptible hybrid, a diminution of the lignin content could be observed upon infection byP. infestans. In the same context, peroxidasic activity raised upon infection byP. infestans in both resistant and susceptible hybrids. Further characterization of the hybrid clones based on the polymorphism of peroxidases was attempted using isoelectric focusing.  相似文献   

19.
Potato is an important crop, grown worldwide. It suffers from many pests and diseases among which late blight, caused by the oomycete Phytophthora infestans, is the worst. The disease is still causing major damage in many potato production areas and control is only possible by applying fungicides frequently. The knowledge on the molecular biology and genetics of the interaction between the plant and the oomycete is developing rapidly. These are relevant fields of study, currently dominated by the discovery of many resistance genes and numerous effector proteins and the analysis of their specific mode of action. These studies may yield essential information needed for the development of durable resistance. The long-term and worldwide effort to breed for resistance so far has had little effect. A novel breeding approach may change this. It is based on cisgenic modification (CM) consisting of marker-free pyramiding of several resistance genes and their spatial and temporal deployment yielding dynamic varieties that contain potato genes only. It is envisioned that this CM approach with potato’s own genes will not only prove societally acceptable but may also result in simplifications in the legislation on use of the CM approach. Various parties in the potato research arena intend to cooperate in this novel approach in a number of developing countries where potato substantially contributes to food security. The use of resources such as land, water and energy improves when the effect of late blight is markedly reduced.  相似文献   

20.
In an experimental breeding scheme to improve late blight (Phytophthora infestans) and white potato cyst nematode (Globodera pallida) resistance of tetraploid potato over three generations of crossing and selection, 15 clones survived the final selection, and these were derived from 15 great-grandparents. There was no direct selection for resistance to Potato virus Y (PVY), but 14 out of the 15 great-grandparents were resistant to PVY and three had extreme resistance. Thirteen of the 15 descendants had PVY resistance and one extreme resistance. This was within the range expected for a random (unselected) sample from the genotypes of the great-grandparents. Hence, we found no evidence for any positive or negative association between PVY resistance and the attributes selected. The conclusion is that laborious selection is not required in every generation when many parents have PVY resistance, including some with more than one copy of a PVY resistance gene or resistance at more than one locus. However, in the future, determining the major virus resistance genes present in potential parents in each generation using diagnostic molecular markers would prevent susceptible × susceptible crosses being made and maximise the number of resistant × resistant ones.  相似文献   

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