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1.
《农产品质量与安全》2017,(4)
为研究土壤交换性钙含量对花生黄曲霉毒素污染的影响,选取黄曲霉毒素污染程度不同的江西樟树、山东临沂、辽宁阜新作为定点观测点,同时种植粤油256、花育25、白沙1016等3个主栽花生品种,连续2年实验结果分析表明,不同试验点土壤交换性钙含量差异显著,江西樟树的土壤交换性钙含量(10.15 cmol/kg)显著低于山东临沂(27.28 cmol/kg)和辽宁阜新(20.02 cmol/kg);土壤交换性钙含量与所产花生的壳、皮、仁中钙含量呈正相关,土壤交换性钙含量越高,花生各部位富集的钙含量也越高;珍珠豆型花生粤油256和白沙1016花生仁和皮的钙含量与黄曲霉侵染指数负相关(r-0.95),花生仁和皮中钙含量越高,花生仁黄曲霉侵染指数越低,抗侵染能力越强。 相似文献
2.
为了解我国花生土壤黄曲霉分布及产毒特征与产后花生黄曲霉毒素污染相关性,本试验从我国4个典型花生产区黄河流域产区(河北保定)、西北产区(新疆吐鲁番)、长江流域产区(湖北黄冈、四川南充)和东南沿海产区(广东湛江)采集花生土壤样品124份。通过对我国不同产区花生土壤中黄曲霉菌的分布及产毒特征研究,评估我国不同产区花生黄曲霉毒素污染风险。结果表明,湖北黄冈和四川南充土壤中黄曲霉检出率、带菌量和黄曲霉毒素B1(AFB1)量均高于其他地区,产后花生受AFB1污染风险最高,其次为广东湛江和新疆吐鲁番,河北保定花生受AFB1污染风险最低。从上述4个产区收集64份花生样品开展产后花生AFB1污染调查,发现湖北黄冈花生AFB1污染情况最严重,检出率为57%,超标率为10%,其次为四川南充和广东湛江,新疆吐鲁番和河北保定花生受AFB1污染较轻。风险评估结果与实际检测结果一致,表明花生土壤中黄曲霉菌数量、产毒菌比例及产毒能力与产后花生AFB1污染呈正相关性。本研究结果为花生黄曲霉毒素污染预警及综合防控提供了理论依据和数据支撑。 相似文献
3.
臭氧降解花生中黄曲霉毒素的设备及应用 总被引：1，自引：0，他引：1
为了高效降解花生中黄曲霉毒素,研制了一套臭氧降解黄曲霉毒素的设备。以人为污染的花生为试验材料,利用此设备研究了臭氧处理时间及其相对湿度对花生脱毒效果的影响。研究结果表明:臭氧能有效降解花生中的黄曲霉毒素,且臭氧处理时间和相对湿度显著影响其降解效果(P<0.05)。在臭氧浓度89mg/L、流速1L/min、搅拌速度70r/min条件下,黄曲霉毒素的较佳降解工艺为:臭氧相对湿度50%,处理时间30min。在此条件下,花生中黄曲霉毒素B1、B2、G1和G2的含量分别从87.53、21.99、9.71和4.38μg/kg降低到15.23、8.31、2.81和2.11μg/kg,降解率分别为82.6%、62.2%、71.1%和51.8%。研究结果可为花生贮藏和加工企业降低花生中的黄曲霉毒素、确保花生食用安全性提供技术参考。 相似文献
4.
为了解析不同培养温度和水分活度对稻谷和大米黄曲霉生长和产毒的影响,揭示温度和水分活度(aw)调控稻米上黄曲霉生长和产毒的分子机制,以湖南黄华占稻谷和黑龙江稻花香大米为原料,分析稻谷和大米的真菌菌相,并采用高效液相色谱法测定稻谷和大米AFB1含量,利用荧光定量PCR分析稻谷和大米水分活度及温度对黄曲霉毒素生物合成关键基因表达的影响。结果表明,当aw降低至0.75以下,稻谷和大米上不适合黄曲霉生长繁殖和产毒。在33℃、aw为0.96条件下大米黄曲霉产毒最多,33℃、aw为0.90条件下大米黄曲霉的生长最好;稻谷则是在温度37℃,aw为0.94和0.92条件下分别为最适产毒和生长,可见黄曲霉在稻谷和大米上生长和产毒的最适条件并不统一。荧光定量PCR结果显示,低温25℃可以促进黄曲霉产毒基因表达,但毒素在转录合成过程中受到了阻抑,高温37℃则抑制部分结构基因的表达,但菌的生长受到极显著影响而导致毒素量极低。因此,稻谷和大米储藏期及加工时,保持较低的aw是有效预防黄曲霉侵染及AFB1污染的关键。本研究结果为制定储藏及加工期稻谷和大米黄曲霉毒素污染的防控措施提供了一定的理论依据和数据支撑。 相似文献
5.
为获得拮抗黄曲霉和降解黄曲霉毒素的生物防治菌株,以烟台黄曲霉污染区域土壤为材料,采用稀释分离法和琼脂扩散法,筛选到一株对黄曲霉有抑制作用且可降解黄曲霉毒素的菌株Y-17-3。根据菌株的形态学特征、生理生化试验结合16S rDNA基因序列分析和系统发育树构建,确定菌株 Y-17-3 为空气芽孢杆菌(Bacillus aerius)。该菌株发酵液经硫酸铵沉淀的抗菌活性及稳定性试验,发现70%饱和硫酸铵沉淀的蛋白粗提物抑制黄曲霉活性最强,可降低黄曲霉孢子的萌发率,抑制菌丝的生长和菌丝球的形成,且该蛋白粗提物对温度、pH值和蛋白酶敏感。菌株Y-17-3能够降解黄曲霉毒素B1,培养6 d时的降解率达90%。综上,所分离的空气芽孢杆菌Y-17-3菌株能够通过产生拮抗蛋白来抑制黄曲霉生长,且具有较强的黄曲霉毒素降解能力,在农业生物防治领域具有一定的应用前景。 相似文献
6.
生猪黄曲霉毒素中毒的诊断与防治 总被引：1，自引：0，他引：1
猪黄曲霉毒素中毒是由于猪误食被黄曲霉或寄生曲霉污染的含有毒素的花生、玉米、麦类、豆类、油粕等而引起,误食后1～2周即可发病.黄曲霉毒素是黄曲霉菌的代谢产物,在高温多雨的季节或保存环境湿度大,24～30℃时在饲料中繁殖旺盛,产生大量毒素,目前发现有20多种,化学性质十分稳定、耐高温,以B1、B2、G1、G2的毒力为最强,对畜牧业生产危害极大.现就黔江区一生猪自繁自养规模养殖场的生猪不明原因陆续发病,随后出现中毒死亡,经临床检查、剖检诊断、病史调查、血液检查,诊断为黄曲霉毒素中毒.现将诊治情况简述如下. 相似文献
7.
8.
壳聚糖-胰蛋白酶抑制剂复合可食性膜的制备及抗黄曲霉活性 总被引：5，自引：4，他引：1
为探索新型生物膜材料的制备方法及抗黄曲霉活性,以壳聚糖和大豆胰蛋白酶抑制剂(TI)提取物为原料,甘油为增塑剂,利用溶液共混流延法制备壳聚糖-TI-甘油复合可食性膜,测试其厚度、表观结构、力学性质、透光率、水蒸气透过率及抗黄曲霉侵染活性。结果表明,当壳聚糖浓度为18mg/mL、TI浓度2mg/mL、甘油浓度12mg/mL和干燥温度45℃时,制备复合膜具有优良抗黄曲霉活性,且综合理化性能最佳。制备壳聚糖-TI-甘油复合膜液涂膜于花生上,接种黄曲霉培养后发现,复合膜对于黄曲霉侵染具有较强的抵抗和抑制作用。 相似文献
9.
为研究香根草篱(Vetiveria zizanioides)对红壤坡耕地土壤酶活性的影响,以典型红壤坡耕地花生+草篱种植模式为研究对象,选取花生常规种植为对照,研究了花生关键生育期香根草篱对表层土壤(0 ~ 20 cm)酶活性的空间影响。研究发现：与花生常规种植相比,香根草篱可以明显提高坡面土壤脲酶、蔗糖酶与过氧化氢酶的含量;栽培植物篱后,坡面土壤脲酶、蔗糖酶与过氧化氢酶活性表现出篱前含量增高,篱下含量降低,形成水平带状分布规律。从花生出苗期-结荚期-成熟期,土壤脲酶、蔗糖酶与过氧化氢酶活性均呈现先增后减的趋势,其中以结荚期较高。采样点与土壤脲酶、蔗糖酶活性呈显著线性相关,3种土壤酶之间的相关性也都达到了显著相关。 相似文献
10.
建立了一种萃取溶剂少、操作简单、灵敏度高的QuECHERS前处理方法,结合超高效液相色谱-串联质谱实现山楂干制品中黄曲霉毒素(AFB_1、 AFB_2、 AFG_1、 AFG_2)、赭曲霉毒素A (OTA)、交链孢酚(AOH)、交链孢酚单甲醚(AME)、展青霉素(PAT)等8种真菌毒素同步定量分析,并将该方法应用于实际山楂干制品中真菌毒素污染分析,了解其实际污染情况。试验以0.2%甲酸的乙腈溶液为提取剂,采用QuECHERS方法进行前处理,应用超高效液相色谱-质谱联用定量分析8种真菌毒素。结果显示, AFB_1、 AFB_2、 AFG_1、 AFG_2、 OTA、 AOH、 AME等7种真菌毒素在1～50μg/L范围内线性关系良好, PAT在5～50μg/L范围内线性关系良好,相关系数均R2≥0.991。回收率为84.3%～111.5%。将建立的方法应用于17个山楂干制品样品分析,其中AOH和AME检出率分别为100%、 88.2%,含量为1.2～9.0μg/kg,其余6种毒素均未检出。结果表明,建立的QuECHERS方法适用于山楂干制品中多种真菌毒素同步定量分析。 相似文献
11.
基于电子鼻的花生有害霉菌种类识别及侵染程度定量检测 总被引：4，自引：3，他引：1
针对花生霉变传统分析方法操作繁琐、时效性差等不足,该研究拟利用电子鼻气体传感技术建立起花生有害霉菌污染的快速检测方法。辐射灭菌花生籽粒分别接种5种谷物中常见有害霉菌(黄曲霉3.17、黄曲霉3.395 0、寄生曲霉3.395、寄生曲霉3.012 4和赭曲霉3.648 6),并于26℃、80%相对湿度条件下储藏9 d至严重霉变。利用电子鼻气体传感器获取不同储藏时期(0、3、6、9 d)花生样品的整体挥发性气味信息。最后,结合多元统计分析方法对电子鼻传感器响应信号进行特征提取,建立了花生中有害霉菌污染程度的定性定量分析模型。结果显示,主成分分析法(principal component analysis,PCA)可成功区分不同霉菌侵染程度的花生样品,线性判别分析(linear discriminant analysis,LDA)模型对样品不同储藏天数判别的准确率均达到或接近100%。花生中菌落总数的偏最小二乘回归分析(partial least squares regression,PLSR)模型的预测决定系数和预测相对均方根误差分别达到0.814 5和0.244 0 lg(CFU/g)。结果表明,应用电子鼻技术快速检测储藏期间花生霉变状况具有一定可行性,可为利用气味信息实现粮食霉菌污染的在线监测提供理论参考。 相似文献
12.
土壤水分对花生根际分泌物中低分子量有机酸的释放及根质外体中铁的积累的影响 总被引：1，自引：0，他引：1
A three-compartments rhizobox was designed and used to study the low-molecular-weight organic acids in root exudates and the root apoplastic iron of “lime-induced chlorosis“ peanut grown on a clacareous soil in realtion to different soil moistrue conditions.Results showed that chlorosis of peanuts developed under condition of high soil mositure level(250 g kg^-1),while peanuts grew well and chlorosis did not develop when soil moisture was managed to a normal level(150 g kg^-1).The malic acid maleic acid and succinic acid contents of chlorotic peanut increased by 108.723,0.029,and 22.446ug cm^-1 ,respectively,compared with healthy peanuts.The content of citric acid and fumaric acid also increased in root exudates of chlorotic peanuts.On Days 28 and 42 of peanut growth,the accumulation of root apoplastic iron in chlorotic peanuts was higher than that of healthy peanuts.From Day 28 to Day 42,the mobilization percentages of chlorotic peanuts and healthy peanuts to root apoplastic iron were almost the smae,being 52.4% and 52.8%,respectively,indicating that the chlorosis might be caused by the inactivation of iron within peanut plant grown on a calcareous soil under soil moisture conditions. 相似文献
13.
Utilization of the major corn (Zea mays) reserve materials (free saccharides, starch, triglycerides, and zein) was monitored during infection of detached kernels by Aspergillus flavus (A. flavus) over a 12-day period. Inoculated whole kernels were compared to noninoculated kernels. Concentrations of sucrose and raffinose in inoculated seed decreased to nearly zero at 6 days, whereas concentrations of these saccharides in noninoculated seed dropped at a considerably slower rate, and significant levels remained at the end of the incubation period. Triglyceride concentrations remained unchanged in the noninoculated seed but dropped continuously after 2 days in the inoculated seed. Starch and zein concentrations did not change during the 12-day incubation period. Aflatoxin B1 was first detected after 2 days and increased to about 20 microg/g (20,000 ppb) after 12 days. Very low aflatoxin concentrations were detected in the noninoculated seed. Significant concentrations of erythritol, arabitol, and mannitol were produced during infection, with peak concentrations occurring at 8 days. Whole seed and germ tissue appeared to support good fungal growth and aflatoxin production, whereas ground tissues and endosperm did not. A. flavus preferentially utilized saccharides as initial carbon substrates followed by triglycerides. When invading nonwounded corn kernels, the fungus selectively targets the germ tissue where these materials are localized in the highest concentrations. 相似文献
14.
Cottonseed storage lipids (primarily triglycerides), in either crude or refined form, were found to support growth and aflatoxin B(1) production by Aspergillus flavus. When lipids were removed from ground whole cottonseed by petroleum ether extraction, aflatoxin production dropped by more than 800-fold. Reconstitution of the lipid-extracted ground whole seed with a crude preparation of cottonseed lipids restored aflatoxin production to the previous levels. Fungal utilization of the three major cottonseed reserve materials, raffinose, triglycerides (refined cottonseed oil), and cottonseed storage protein, was monitored in vitro over a 7 day fermentation period. The fermentation medium contained the reserve compounds in proportions approximating those found in mature cottonseed. A. flavus rapidly converted raffinose to fructose and melibiose, presumably by action of invertase, and then hydrolyzed the melibiose. These simple sugars apparently supported initial growth and aflatoxin B(1) production. Raffinose and the resulting melibiose were nearly exhausted by day 2. Fungal hydrolysis of triglycerides began as exhaustion of carbohydrate approached. After day 2, rapid catabolism of the released fatty acids began and coincided with glucose regeneration through gluconeogenesis, which peaked on day 6. The fungus did not preferentially utilize specific fatty acids. A. flavus also produced a number of storage metabolites, including arabitol, erythritol, mannitol, and trehalose. Mannitol was produced in much higher concentrations than the other storage metabolites. Selective use of simple carbohydrates by A. flavus to drive aflatoxin production may suggest strategies for reducing vulnerability of cottonseed to aflatoxin contamination. 相似文献
15.
Liquid chromatographic method for determination of aflatoxins B1, B2, G1, and G2 in corn and peanut products: collaborative study 总被引：1，自引：0，他引：1
D L Park S Nesheim M W Trucksess M E Stack R F Newell 《Journal of the Association of Official Analytical Chemists》1990,73(2):260-266
A collaborative study of a liquid chromatographic method for the determination of aflatoxins B1, B2, G1, and G2 was conducted in laboratories located in the United States, Canada, South Africa, and Switzerland. Twenty-one artificially contaminated raw peanuts, peanut butter, and corn samples containing varying amounts of aflatoxins B1, B2, G1, and G2 were distributed to participating laboratories. The test portion was extracted with methanol-0.1N HCl (4 + 1), filtered, defatted with hexane, and then partitioned with methylene chloride. The concentrated extract was passed through a silica gel column. Aflatoxins B1 and G1 were derivatized with trifluoroacetic acid, and the individual aflatoxins were determined by reverse-phase liquid chromatography with fluorescence detection. Statistical analysis of the data was performed to determine or confirm outliers, and to compute repeatability and reproducibility of the method. For corn, relative standard deviations for repeatability (RSDr) for aflatoxin B1 ranged from 27.2 to 8.3% for contamination levels from 5 through 50 ng/g. For raw peanuts and peanut butter, RSDr values for aflatoxin B1 were 35.0 to 41.2% and 11.2 to 19.1%, respectively, for contamination levels from 5 through 25 ng/g. RSDr values for aflatoxins B2, G1, and G2 were similar. Relative standard deviations for reproducibility (RSDr) for aflatoxin B1 ranged from 15.8 to 38.4%, 24.4 to 33.4%, and 43.9 to 54.0% for corn, peanut butter, and raw peanuts, respectively. The method has been adopted official first action for the determination of aflatoxins B1, B2, G1, and G2 in peanut butter and corn at concentrations greater than or equal to 13 ng total aflatoxins/g. 相似文献
16.
Aflatoxins in domestic and imported foods and feeds 总被引：4，自引：0，他引：4
G E Wood 《Journal of the Association of Official Analytical Chemists》1989,72(4):543-548
Aflatoxins, metabolic products of the molds Aspergillus flavus and A. parasiticus, may occur in foods and feeds. These toxins cannot be entirely avoided or eliminated from foods or feeds by current agronomic and manufacturing processes and are considered unavoidable contaminants. To limit aflatoxin exposure, the U.S. Food and Drug Administration (FDA) has set action levels for these toxins in foods and feeds involved in interstate commerce. FDA continually monitors food and feed industries through compliance programs. This report summarizes data generated from compliance programs on aflatoxins for the fiscal year 1986. Commodities sampled included peanuts and peanut products, corn and corn products, tree nuts, cottonseed, milk, spices, manufactured products, and miscellaneous foods and feeds. Correlations were highest between aflatoxin contamination and geographical areas for corn/corn products and cottonseed/cottonseed meal. Higher incidences of aflatoxin contamination in corn and corn products designated for human consumption were observed in samples collected in the southeastern states (32 and 28%, respectively). A higher incidence of contamination was observed in corn designated for animal feed from Arkansas-Texas (74%) than from the southeastern states (47%). Only 3% of feed corn from corn belt states contained detectable aflatoxins. All aflatoxin-contaminated cottonseed was collected in the Arizona-California area; 80% of cottonseed meal analyzed from this area also contained detectable levels of aflatoxins.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
17.
收获时期及干燥方式对花生品质的影响 总被引：3，自引：3，他引：0
为探索不同收获期和后熟干燥方式对花生品质的影响,该研究以泰花5号花生为试验对象,采用在株晾干法、鲜摘晾干法、鲜摘催干法3种方法对3个时期收获的花生进行后熟干燥品质对比测试分析。结果表明,在同一收获期中,在株晾干法花生百果质量、百仁质量显著高于其他2种方法,该后熟干燥方法的增重作用随收获期提前而更明显(P0.05);但在相同后熟干燥方法中,提前2周收获的干燥荚果百果质量、百仁质量均显著低于前1周和原定收期收获的花生荚果(P0.05)。自然晾晒干燥期间,在株晾干花生果壳、果仁含水率均高于同期鲜摘晾干果壳、果仁含水率,两种晾干方式含水率差异在初期逐渐增加、随后逐渐减小直至达到相当的最终含水率。鲜摘晾干和鲜摘催干果仁粗蛋白、粗脂肪均未见显著差异(P0.05),而在株晾干果仁粗蛋白、粗脂肪含量分别增加了3%、2%左右;而收获期越早,果仁粗蛋白和粗脂肪含量越低。在果仁不饱和脂肪酸总相对含量上,鲜摘晾干、在株晾干果仁与新鲜果仁未见差异(P0.05),但机械催干果仁显著低于新鲜果仁(P0.05)。在果仁氨基酸组成方面,经3种不同后熟干燥方法后,8种主要氨基酸及氨基酸总含量均呈现在株晾干含量最高、鲜摘晾干其次、机械催干最低的差异(P0.05)。在株晾干花生果柄横断面显微结构观察表明,果柄在干燥初期仍保留对水分、养分等物质输导、贮藏的空间通道,为荚果的物质代谢和积累提供必要条件。该研究结果为花生生产实践提供参考。 相似文献
18.
用于污染黄曲霉毒素花生分选的荧光信号研究 总被引：2，自引：2，他引：0
为在加工前将黄曲霉毒素超限的带衣花生米从原料中剔除,参照已有的色选系统,提出一种依据黄曲霉毒素含量超限带衣花生米的专属荧光信号进行逐粒分选的技术构想。采用Cary Eclipse荧光分光光度计测定100粒外观具有代表性的带衣花生米表面的紫外-荧光规律,通过与免疫亲和层析净化荧光光度法(GB/T18979-2003)检测结果对比,判定了黄曲霉毒素超限带衣花生米的荧光光谱特征;通过绘制450/490、460/490荧光强度比值的箱线图,评估了表面荧光法判断黄曲霉毒素超限带衣花生米的准确率;在搭建的荧光成像系统上,对黄曲霉毒素超限带衣花生米进行了荧光成像。检测发现,在365 nm波长激发下,黄曲霉毒素超限带衣花生米在420~460 nm处有荧光峰;以450/490荧光强度比值为依据剔除超限值带衣花生米的判断准确率为81%;a.u.40的带衣花生米可在图像中呈现亮蓝荧光光斑。表明表面荧光信号可作为带衣花生米在线、无损、逐粒分选的专属光学信号,用于黄曲霉毒素超限带衣花生米的剔除。 相似文献