凝胶色谱净化-超高效液相色谱法测定食用油中苯并芘残留

建立了凝胶色谱净化-超高效液相色谱(GPC-UPLC)测定食用油中苯并芘的分析方法.样品用V乙酸乙酯∶V环己烷=1∶1提取,去除大分子油脂.以BEH C18柱(1.7 μm,2.1 mm×50 mm)为分离柱,V乙腈∶V水=88∶12为流动相,在优化试验条件下,苯并芘的检出限为0.05μg/kg,定量限为0.1 μg/kg,苯并芘的线性范围为0.1～10 μg/kg,相关系数为0.997.样品在0.1,0.2及10 μg/kg三个加标水平的加标回收率为70.1％～97.5％,相对标准偏差为0.9％～10.7％.该方法灵敏度高、自动化程度高,可用于食用油中苯并芘的常规检测.     

谷物及土壤中氟虫腈残留分析方法研究

本文报道了稻米、小麦、玉米等谷物及水稻秸秆和土壤中氟虫腈残留量检测方法。样品采用乙腈为提取溶剂,超声波振荡提取,谷物及秸秆提取液经柱层析净化,采用气相色谱电子俘获检测器检测。在0.01～0.5mg/kg的添加浓度范围内,氟虫腈的平均回收率在80.60%～99.66%之间,相对标准偏差低于9%,最小检测浓度为0.01mg/kg。方法的灵敏度与准确度符合农药残留分析要求。     

免疫亲和柱净化高效液相色谱荧光法测定调味品中赭曲霉毒素A

建立了免疫亲和柱净化高效液相色谱法测定调味品中赭曲霉毒素A。样品用甲醇与NaHCO3体积比为60:40的溶液提取,经免疫亲和色谱柱纯化,应用液相色谱法检测。结果表明,空白样品按照质量分数为1.0,20,50μg/kg添加赭曲霉毒素A,回收率为75.0%～102.0%,精密度小于15%,方法检测灵敏度为0.5μg/kg。免疫亲和柱净化高效液相色谱法测定调料中赭曲霉毒素A是一种简单、快速、准确的方法。     

免疫亲和柱净化高效液相色谱法测定坚果中黄曲霉毒素

建立了免疫亲和柱净化高效液相色谱法测定坚果中黄曲霉毒素B1,B2,G1和G2总量。样品用甲醇—水提取,经免疫亲和色谱柱纯化,应用液相色谱法检测。试验结果表明:空白样品分别按照5.2,26,52μg/kg添加黄曲霉毒素,回收率为81.3%～96.0%,精密度<10%,黄曲霉毒素B1,B2,G1和G2的检测灵敏度分别为0.10,0.05,0.10,0.15μg/kg。免疫亲和柱净化高效液相色谱法测定坚果中黄曲霉毒素B1,B2,G1,G2总量,是一种简单、快速和准确的方法。     

小麦中杂色曲霉毒素的硅镁吸附柱层析分离纯化及HPLC的定量分析

目的:建立小麦中杂色曲霉毒素含量的高效液相色谱检测方法。方法:样品中的杂色曲霉毒素经正己烷提取后,采用国产硅镁型吸附剂制备层析柱净化后,运用高效液相色谱法测定,色谱柱为Nova-Pak C18柱,以甲醇-水(70∶30,V/V)为流动相,流速0.7mL/min,检测波长为246nm进行检测。结果:该方法平均加标回收率为79.26%,相对标准偏差为3.84%,最低检出量为0.017μg/kg。结论:本方法简便、准确、成本低,可用于小麦中杂色曲霉毒素含量的测定。     

甲草胺在玉米籽粒上的QuEChERS-HPLC残留分析方法探究

建立了一种简单、快速、环保的甲草胺在玉米籽粒中的QuEChERS-HPLC残留分析方法。样品用极少量的乙腈提取,用N-丙基乙二胺（PSA）和石墨化炭黑（GCB）净化,高效液相色谱（紫外检测器）检测甲草胺浓度。色谱柱为C18反相柱(250 mm×4.6 mm×5.0μm),流动相乙腈和水（70:30）溶液。对玉米中的甲草胺进行不同水平的添加回收率实验,在考察浓度范围内线性关系良好(R2≥0.994);在0.2~10 mg/kg添加水平内,平均加标回收率为96.7%~113.8%,相对标准偏差（RSD）为3.2%~15.3%;检出限和定量限分别为0.015 mg/kg、0.05 mg/kg。该方法的精密度、灵敏度和准确度符合农药残留分析的要求。     

高效液相色谱-串联质谱法测定稻谷中氯虫苯甲酰胺残留

建立了使用石墨化碳/氨基固相萃取柱进行净化的测定稻谷中氯虫苯甲酰胺的残留量的方法。样品经乙腈提取后,过石墨化碳/氨基固相萃取柱净化,基本消除基质效应。以0.1%甲酸水-乙腈为流动相梯度洗脱,正离子多反应监测模式进行测定,可直接使用溶剂配制的标准点进行校正,不需要使用基质标准曲线。检出限可达到0.3μg/kg,在质量浓度1μg/L～100μg/L之间线性相关良好。添加浓度为1μg/kg、10μg/kg、20μg/kg时,回收率在89.1%～99.2%,相对标准偏差均小于10%。     

HPLC-ELSD法测定啤酒糟酶解物中低聚木糖

为建立啤酒糟酶解物中低聚木糖HPLC-ELSD检测方法,将啤酒糟酶解物用纯水提取,色谱柱为COSMOSIL Sugar-D分析柱(250 mm×4.6 mm,5μm),流动相为乙腈-水(69:31,V/V),流速为0.9 mL/min,柱温40℃,进样量3μL,Evaporator Temperature为78℃,载气流速为1.6 L/min,载气压力为0.5 MPa,采用峰面积外标法定量检测低聚木糖含量。结果表明,木二糖～木五糖分别在0.024～0.245 mg/mL质量浓度范围内呈良好的线性关系,检出限分别为0.0245、0.0245、0.02425、0.024 mg/mL,定量限分别为0.0907、0.0907、0.08981、0.8889 mg/mL,RSD分别为0.203%、0.224%、0.233%、0.252%,样品加标回收率为97.31%～99.83%。该方法具有灵敏度高、重复性好等优点,可用于啤酒糟酶解物中低聚木糖的检测。     

赤霉病毒素（DON）去毒技术的研究

将天然污染赤霉病毒素脱氧雪腐镰刀菌烯醇(deoxynivalenol)的小麦,用清水淘洗浮选后再经过加工制粉,可以使毒素含量为2.3mg/kg的小麦中脱氧雪腐镰刀菌烯醇(DON)的量减少75％,使毒素含量为1.2mg/kg的降低60％;6％的过氧化氢(加1％NaOH)去毒效果较明显,DON的含量可降低59％;用1％的亚硫酸氢钠处理的小麦,可去除毒素约30％;20％水分的小麦在100％氨气(加10％Na_2CO_3)中放置18小时,在10％氯气中暴露0.5小时,均可使毒素含量降低30％。     

大米、苹果中吡蚜酮残留量测定

建立了吡蚜酮（pymetrozine）在大米和苹果中的残留分析方法。大米样品以乙腈+氨水（10：1,v:v）提取,苹果样品用乙腈提取,提取液经固相萃取小柱净化,高效液相色谱(VWD)测定。吡蚜酮的最小检测量为6.0×10-10g,最低检测浓度为0.02mg/kg。大米中吡蚜酮的添加（浓度0.05～1.0mg&#8226;kg-1）回收率为75.99%～96.03%,变异系数分别为1.64%～4.74%;苹果中吡蚜酮的添加（浓度为0.05～1.0 mg&#8226;kg-1）回收率为74.84%～86.28%,,变异系数分别为1.67%～5.43%。该方法的准确性和灵敏度均符合农药残留分析要求。     

Resistance to Fusarium head blight and deoxynivalenol accumulation in wheat

Fusarium head blight (FHB), caused by Fusarium graminearum Schwabe (telomorph =Gibberella zeae (Schw.)), is an important wheat disease world‐wide. Production of deoxynivalenol (DON) by F. graminearum in infected wheat grain is detrimental to livestock and is also a safety concern in human foods. An international collection of 116 wheat lines was evaluated for FHB resistance and concentration of DON in grain. Plants were inoculated with mixed isolates of F. graminearum in the greenhouse by injecting conidia into a single spikelet of each spike and in the field by scattering F. graminearum‐infected wheat kernels on the soil surface. FHB symptoms were evaluated by visual inspection in both the greenhouse and field, and DON was analysed by HPLC. Significant differences in FHB ratings and DON levels were observed among cultivars. In the greenhouse test, visual symptoms varied from no spread of FHB from the inoculated spikelet to spread throughout the spike, and DON levels ranged from trace levels to 283 mg/kg. In the field test, DON ranged from 2.8 to 52 mg/kg. The greenhouse test identified 16 wheat lines from various origins that accumulated less than 2 mg/kg DON. These lines may be useful as sources for breeding wheat cultivars with lower DON levels. Correlation coefficients were significant between FHB symptom ratings, seed quality traits, and DON levels. Thus, the percentage of scabbed spikelets and kernels can be generally used to predict DON levels in harvested wheat grain. In breeding programmes, selection for plants having few scabbed spikelets and scabbed kernels is most likely to result in low DON levels.     

Correlations among Fusarium culmorum head blight resistance, fungal colonization and mycotoxin contents in winter rye

Fusarium culmorum head blight infections may lead to accumulation of toxic metabolites in winter rye grain. To estimate the correlation between resistance traits, fungal colonization and accumulation of deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-AcDON) and zea-ralenone (ZEA), 27 winter rye single-cross hybrids were artificially inoculated in 1992 and 1993. Resistance traits were head blight rating and grain weight of the inoculated relative to the non-inoculated plots. Fungal colonization was determined by the analysis of ergosterol (ERG) content in the grain. Head blight rating and relative grain yield showed a medium to high disease severity and ERG indicated a considerable fungal colonization of the kernels with a mean of 85 mg/kg in 1992 and 66 mg/kg in 1993. DON content among genotypes ranged from 0.7–28 mg/kg in 1992 and from 11 to 35 mg/kg in 1993. 3-AcDON and ZEA contents were low in both years with overall means of 1.1 and 0.09 mg/kg, respectively. Across both years, considerable genotypic variation was found for head blight rating, relative grain weight, and ERG content with medium to high heritabilities (0.6–0.7). For the mycotoxin contents, however, genotype-year interaction variance was the most important source of variation. The correlations between relative grain weight and DON, 3-AcDON, or ZEA were low in 1992 (r ～ 0.3), but considerably higher in 1993 (r ～ 0.7, P = 0.01). In contrast, correlation between relative grain weight and ERG was significant in both years (r ～ 0.5, P = 0.01). In F. culmorum head blight infections, DON, 3-AcDON and ZEA contents appear to be affected, at least partially, by different environmental factors than resistance traits and fungal colonization.     

小麦粉中单端孢霉烯族毒素的检测方法

使用GC/MS建立了小麦粉中脱氧雪腐镰刀菌烯醇和雪腐镰刀菌烯醇2种毒素同时检测的方法。前处理0.5倍浓缩,外标法定量,回收率超过70%,定量下限为0.01 mg/kg,0.005～0.5 mg/L标准溶液的相关系数大于0.99。该方法操作简单、重现性和准确度高,非常适用于脱氧雪腐镰刀菌烯醇和雪腐镰刀菌烯醇的检测。     

用化学方法脱除赤霉病麦毒素的研究

对天然污染脱氧雪腐镰刀菌烯醇（ＤＯＮ）毒素的小麦,进行机械加工去皮和化学试剂处理脱毒。结果机械加工去皮可以去除２３．６％～３４．７％的ＤＯＮ毒素。化学试剂处理中,对麦粒的脱毒效果以０．１ｍｏｌ／Ｌ碳酸钠为最好,去毒效果达到８２．１％～８５．０％,平均为８３．９％;其次是１％亚硫酸氢钠,其ＤＯＮ降低率为６９．９％;４％过氧化氢和５％石灰水对ＤＯＮ降低率分别为４５．１％和２１．８％;对麸皮的脱毒效果也     

Effects of genotype and genotype—environment interaction on deoxynivalenol accumulation and resistance to Fusarium head blight in rye, triticale, and wheat

Fusarium culmorum is one of the most important Fusarium species causing head blight infections in wheat, rye, and triticale. It is known as a potent mycotoxin producer with deoxynivalenol (DON), 3‐acetyl deoxynivalenol (3‐ADON), and nivalenol (NIV) being the most prevalent toxins. In this study, the effect of winter cereal species, host genotype, and environment on DON accumulation and Fusarium head blight (FHB) was analysed by inoculating 12 rye, eight wheat, and six triticale genotypes of different resistance levels with a DON‐producing isolate at three locations in 2 years (six environments). Seven resistance traits were assessed, including head blight rating and relative plot yield. In addition, ergosterol, DON and 3‐ADON contents in the grain were determined. A growth‐chamber experiment with an artificially synchronized flowering date was also conducted with a subset of two rye, wheat and triticale genotypes. Although rye genotypes were, on average, affected by Fusarium infections much the same as wheat genotypes, wheat accumulated twice as much DON as rye. Triticale was least affected and the grain contained slightly more DON than rye. In the growth‐chamber experiment, wheat and rye again showed similar head blight ratings, but rye had a somewhat lower relative head weight and a DON content nine times lower than wheat (3.9 vs. 35.3 mg/kg). Triticale was least susceptible with a five times lower DON content than wheat. Significant (P = 0.01) genotypic variation for DON accumulation existed in wheat and rye. The differences between and within cereal species in the field experiments were highly influenced by environment for resistance traits and mycotoxin contents. Nevertheless, mean mycotoxin content of the grain could not be associated with general weather conditions in the individual environments. Strong genotype‐environment interactions were found for all cereal species. This was mainly due to three wheat varieties and one rye genotype being environmentally extremely unstable. The more resistant entries, however, showed a higher environmental stability of FHB resistance and tolerance to DON accumulation. Correlations between resistance traits and DON content were high in wheat (P = 0.01), with the most resistant varieties also accumulating less DON, but with variability in rye. In conclusion, the medium to large genotypic variation in wheat and rye offers good possibilities for reducing DON content in the grains by resistance selection. Large confounding effects caused by the environment will require multiple locations and/or years to evaluate FHB resistance and mycotoxin accumulation.     

Comparison of rye,triticale, durum wheat and bread wheat genotypes for Fusarium head blight resistance and deoxynivalenol contamination

Small-grain winter cereal crops can be infected with Fusarium head blight (FHB) leading to mycotoxin contamination and reduction in grain weight and quality. Although a number of studies have investigated the genetic variation of genotypes within each small-grain cereal, a systematic comparison of the winter crops rye, triticale, durum and bread wheat for their FHB resistance, Fusarium-damaged kernels (FDK) and deoxynivalenol (DON) contamination across species is still missing. We have therefore evaluated twelve genotypes each of four crops widely varying in their FHB resistance under artificial infection with one DON-producing F. culmorum isolate at constant spore concentrations and additionally at crop-specific concentrations in two environments. Rye and triticale were the most resistant crops to FHB followed by bread and durum wheat at constant and crop-specific spore concentrations. On average, rye accumulated the lowest amount of DON (10.08 mg/kg) in the grains, followed by triticale (15.18 mg/kg) and bread wheat (16.59 mg/kg), while durum wheat had the highest amount (30.68 mg/kg). Genotypic variances within crops were significant (p ≤ .001) in most instances. These results underline the differing importance of breeding for FHB resistance in the different crops.     

粮食中DON-免疫亲和层析净化高效液相色谱法的回收率方法比较

用免疫亲和层析净化高效液相色谱法测定粮食中的脱氧雪腐镰刀菌烯醇,且与GB/T 23503-2009《食品中脱氧雪腐镰刀菌烯醇的测定免疫亲和层析净化高效液相色谱法》、Romer labs实验室推荐方法、实验室优化方法进行比较。本实验方法在前两种方法的基础上优化后,在0.5mg/kg~5mg/kg的加标水平下,回收率在90.3%~100.2%,RSD在1.2%~2.0%之间,最低检出限则为44μg/kg,定量限为146μg/kg,能够很好的满足实验室分析要求。     

高效液相色谱-紫外法同时检测小麦中DON、15ACDON和3ACDON

建立了测定小麦中B型单端孢酶烯族毒素脱氧雪腐镰刀菌烯醇(deoxynivalenol, DON)、3-乙酰脱氧雪腐镰刀菌烯醇(3-acetyldeoxynivalenol, 3-ACDON)和15-乙酰脱氧雪腐镰刀菌烯醇(15-acetyldeoxyni-valenol, 15-ACDON)的高效液相色谱-紫外(HPLC-UV)检测方法。用水提取小麦样品,提取液经无水乙醇等体积沉淀,再结合Oasis HLB固相萃取小柱可取得较好的净化效果。采用乙腈/0.005%磷酸水溶液二元梯度洗脱程序在高效液相色谱-紫外检测器上完成DON、15ACDON和3ACDON的定性定量分析。结果表明,在0.5~15.0 mg L^-1线性范围内,DON、15ACDON和3ACDON的平均加标回收率分别为89.8%、93.4%和92.9%,相对标准偏差分别为2.2%、2.0%和2.5% (n=3);检测限分别为12.2、10.5和16.7 μg kg^-1。该方法准确、重现性好,样品净化方法使杂峰干扰少,大幅减少有机溶剂的使用,成本低,适用于小麦中B型单端孢酶烯族毒素的大批量检测。     

氯苯嘧啶醇在苹果中残留检测方法的研究

本文建立了苹果中氯苯嘧啶醇的残留检测方法,用丙酮/水为提取溶剂,机械振荡法提取,二氯甲烷液液分配,弗罗里硅土柱层析净化,气相色谱电子俘获检测器（GC-ECD）检测。添加浓度为0.03mg/kg、0.3mg/kg、1.0mg/kg时,平均添加回收率分别为103.12%、86.06%和91.76%,变异系数分别为0.03%、0.12%和3.55%。方法的最小检出浓度为0.00375mg/kg,满足农药残留分析的要求。     

Genetic variation for head blight resistance in triticale caused by Fusarium graminearum isolates of different deoxynivalenol production

Summary Fusarium head blight infection causes severe yield losses and contamination of the grain with mycotoxins in triticale (× Triticosecale Wittmack) grown in temperate and semihumid areas. In a two-year experiment thirty-six genotypes were inoculated separately with two isolates of Fusarium graminearum differing fivefold in their in vitro deoxynivalenol (DON) production and the effect on various traits was studied. All traits were significantly affected by head blight. The two isolates differed considerably in their aggressiveness resulting in a mean reduction of grain weight per spike of almost 25% and 50%, respectively. Inter-annual correlation was high for average disease rating (r=0.63, P<-0.01) and low for the other traits. Therefore, disease rating, averaged from two to three records, was regarded a suitable criterion for screening purposes. The effect of isolates on genotypes was not stable over years. The mean DON content of five genotypes with diverse resistance levels was 68 mg kg^-1. In vitro DON production of the two isolates used for inoculation did not correspond to their aggressiveness and DON contamination of the grain.