重组猪抑制素蛋白质中毒素残留检测及其理化稳定性     

李辉  翟颖超  窦晓  张甜  果双双  施振旦 《江苏农业学报》2015,31(2)

为探索纯化的重组猪抑制素蛋白质毒素残留情况以及重组猪抑制素蛋白质稳定性,本研究利用鲎试剂、气相色谱和SDS-PAGE方法对重组猪抑制素蛋白质中的细菌内毒素、β-巯基乙醇的残留量及其蛋白质在不同温度、极端p H值和反复冻融条件下的稳定性进行检测。结果显示,经过3次等电点沉淀洗涤后,重组猪抑制素蛋白质中细菌内毒素和β-巯基乙醇的残留量大幅减少。通过在不同温度下的处理发现,重组猪抑制素蛋白质在4℃环境下较稳定,可以长期保存;但在37℃时,稳定性快速下降,随着温度上升而降解加速。通过极端p H值和反复冻融试验发现,重组猪抑制素蛋白质对极端p H值和反复冻融具有较好的耐受性。  相似文献   

不同基质活性炭对阿特拉津吸附特性研究     

杨峰山  孙丛  于苹艳  马玉堃  付海燕  刘春光 《中国农学通报》2020,36(12):68-72

为了解决阿特拉津给土壤带来的污染问题以及寻找吸附效果较好的活性炭基质,本研究利用高效液相色谱(HPLC)技术检测了阿特拉津溶液和悬浮液经煤、木、果和竹质4种生物炭处理后的残留量,并对其在阿特拉津溶液和土壤中的吸附动态进行检测。结果表明,煤质活性炭对初始浓度为100 mg/L和10 mg/L的阿特拉津溶液和悬浮液的吸附效果较好,其吸附率为5.651%~68.42%;当阿特拉津初始浓度为100 mg/L时,煤质活性炭在40 min时对阿特拉津溶液的吸附率高达23.49%;与对照组相比,当阿特拉津的初始浓度为100 mg/L时,土壤中阿特拉津经煤质活性炭处理42天后的残留浓度最低,活性炭吸附率达到91.39%。综上,煤质活性炭能有效降解溶液及土壤中阿特拉津含量,这将为阿特拉津污染土壤的改良研究奠定基础。  相似文献   

气相色谱-串联质谱法测定柑橘中5种杀螨剂残留     

苏旭  李国烈  彭海燕  杜鑫  覃明丽  蒋金芳 《农药科学与管理》2020,41(4):46-52

建立了气相色谱-串联质谱法(GC-MS/MS)检测柑橘中5种杀螨剂残留分析方法。样品经乙腈提取、氯化钠盐析后,取有机相用Qu EChERS方法净化,利用GC-MS/MS在多反应监测(MRM)模式下进行测定,外标法定量。5种杀螨剂在0.005~0.5mg/L浓度范围内呈现良好的线性关系,相关系数r^2均>0.996,方法定量限为0.005 mg/kg。在0.005、0.01和0.1mg/kg 3种添加水平下,加标回收率为70.6%~111.3%,相对标准偏差(RSD)为1.07%~14.64%。本方法简便、重现性良好,可用于柑橘类水果样品中杀螨剂的日常检测。  相似文献   

广西主要动物源性产品中磺胺二甲嘧啶残留调查与分析     

马玲  陈凤莲  凌丹  李志源  骆永泉  李丹  张怡轩  吴健敏 《中国畜牧兽医》2018,45(11):3286-3295

为了解广西动物源性产品中磺胺二甲嘧啶（SM₂）残留情况，本研究采用磺胺二甲嘧啶化学发光酶免疫分析法（SM₂-CLEIA）对2013-2017年采集的4 637份动物源性产品进行检测，共检出超标样品122份，涉及鲜乳、猪肉、水产品和猪尿，其中超标猪尿92份，SM₂含量100.51~860.44 μg/kg，猪尿中抗生素残留会污染水体、土壤，再通过动植物的富集作用进入食物链，危害人类健康，应引起重视；而本次受检的水牛奶、鸡肝脏、鸭肝脏、鸭肉均合格。所有受检样品超标率逐年下降，同时规模化养殖场样品合格率高于农村散养户、超市高于农贸市场。不同年份超标样品含量以2014年最高。采用食品安全指数（IFS）对广西动物源性食品中SM₂残留风险进行评估，结果均远小于1，说明在广西地区，现有的SM₂残留对人体的潜在危害较低。  相似文献   

中国和欧盟动物源性产品中药物残留限量差异性分析(一)     

程坚  李婷婷  娄鹏祥 《安徽农业科学》2017,45(36):69-71,160

将中国和欧盟动物源性产品中药物残留标准进行了对比,同时结合TBT/SPS预警数据库,找出二者差异性,并提出了改进建议。  相似文献   

Effect of conservation agriculture on soil organic and inorganic carbon sequestration and lability: A study from a rice–wheat cropping system on a calcareous soil of the eastern Indo-Gangetic Plains     

Abir Dey  Brahma Swaroop Dwivedi  Ranjan Bhattacharyya  Siba Prasad Datta  Mahesh Chand Meena  Raj K. Jat  Raj Kumar Gupta  Mangi Lal Jat  Vinod Kumar Singh  Debarup Das  Ravi G. Singh 《Soil Use and Management》2020,36(3):429-438

Increasing soil carbon (C) in arable soils is an important strategy to achieve sustainable yields and mitigate climate change. We investigated changes in soil organic and inorganic carbon (SOC and SIC) under conservation agriculture (CA) in a calcareous soil of the eastern Indo-Gangetic Plains of India. The treatments were as follows: conventional-till rice and wheat (CT-CT), CT rice and zero-till wheat (CT-ZT), ZT direct seeded rice (DSR) and CT wheat (ZT-CT), ZTDSR and ZT wheat without crop residue retention (ZT-ZT), ZT-ZT with residue (ZT-ZT+R), and DSR and wheat both on permanent beds with residue (PB-PB+R). The ZT-ZT+R had the highest total SOC in both 0–15 and 15–30 cm soil layers (20% and 40% higher (p < .05) than CT-CT, respectively), whereas total SIC decreased by 11% and 15% in the respective layers under ZT-ZT+R compared with CT-CT. Non-labile SOC was the largest pool, followed by very labile, labile and less labile SOC. The benefits of ZT and residue retention were greatest for very labile SOC, which showed a significant (p < .05) increase (~50%) under ZT-ZT+R compared with CT-CT. The ZT-ZT+R sequestered ~2 Mg ha⁻¹ total SOC in the 0–15 cm soil layer in 6 years, where CT registered significant losses. Thus, the adoption of CA should be recommended in calcareous soils, for C sequestration, and also as a reclamation technique.  相似文献   

供氮方式对冬马铃薯氮肥利用效率及氮素去向的影响   总被引：2，自引：0，他引：2  

韦剑锋  宋书会  梁振华  韦冬萍  韦巧云  梁和 《核农学报》2016,(1):178-183

以马铃薯费乌瑞它为试材,采用田间微区~(15)N示踪技术,研究施N量160kg·hm~(-2)全部基施(T1)、55%基施+45%在齐苗期追施(T2)、55%基施+30%在齐苗期追施+15%在现蕾期追施(T3)3种方式,对冬马铃薯氮肥利用效率及去向的影响。结果表明:马铃薯吸收的N约46%~52%来源于当季施用的氮肥,48%~54%来自土壤和种薯;肥料N利用率为35.16%~39.99%,残留率为47.71%~51.78%,损失率为8.23%~15.50%。3种施氮方式下,肥料N主要残留在0~15cm土层。随施氮时间后移,肥料N残留在0~15cm土层呈上升趋势,在15~45cm土层呈下降趋势。施氮方式对马铃薯干物质积累总量和块茎干物质积累量影响不明显,但T3肥料N利用率、肥料N残留率明显大于T1、T2。因此,综合经济效益和环境效益,T3施氮方式的效果较为理想。本研究为马铃薯氮素养分的有效管理提供了指导依据。  相似文献   

基于点评估方法的两广地区番木瓜中农药残留膳食暴露风险研究     

郭宏斌  刘福现  林玲  叶剑芝  杨春亮 《热带作物学报》2020,41(12):2548-2554

为评估两广地区番木瓜中主要农药的残留情况及其产生的风险,采集了广东、广西地区40个生产基地的番木瓜样品进行测试分析,研究其生产过程中使用的杀虫剂、杀菌剂、杀螨剂和植物生长调节剂等各种农药残留情况,并对我国不同人群的膳食暴露风险进行了评估。结果显示,40批次番木瓜中检出农药残留32批次;在检出的32份番木瓜样品中,检出率超过10%的有咪鲜胺、吡虫啉、多菌灵、啶虫脒和苯醚甲环唑5种农药,检出率分别为51.1%、21.5%、13.3%、11.1%、10.9%。采用点评估方法,选择检出率在10%以上的咪鲜胺、吡虫啉、多菌灵、啶虫脒和苯醚甲环唑,进行农药残留慢性膳食摄入风险（%ADI）评估、急性膳食摄入风险（%ARfD）评估,并进行不同消费人群暴露点评估。结果显示：检出的5种农药%ADI均低于100.00%,为0.00023%~0.0059%;%ARfD远低于100%,为0.50%~28.3%,5种农药的急性和慢性摄入风险均为儿童高于成年人,绝大多数女性的摄入风险高于男性;5种农药急性摄入风险均高于慢性摄入风险,风险水平由高到低为咪鲜胺>啶虫脒>苯醚甲环唑>多菌灵>吡虫啉,但点评估结果均远低于100%,说明通过食用番木瓜摄入的农药残留极其微量,不会对人体产生急性或慢性风险。  相似文献   

Effects of cover crop growth and decomposition on the distribution of aggregate size fractions and soil microbial carbon dynamics          下载免费PDF全文

D. Linsler  M. Kaiser  R. Andruschkewitsch  C. Piegholdt  B. Ludwig 《Soil Use and Management》2016,32(2):192-199

Although the effects of cover crops (CC) on various soil parameters have been fully investigated, less is known about the impacts at different stages in CC cultivation. The objective of this study was to quantify the influence of CC cultivation stages and residue placement on aggregates and microbial carbon (C_mic). Additionally, the influence of residue location and crop species on CO₂ emissions and leached mineralized nitrogen (N_min) during the plant degradation period was also investigated. Within an incubation experiment, four CC species were sown in soil columns, with additional columns being kept plant‐free. After plant growth, the columns were frozen (as occurs in winter under field conditions) and then incubated with the plant material either incorporated or surface‐applied. With CC, concentrations of large and medium macroaggregates were twice that of the fallow, confirming positive effects of root growth. Freezing led to a decrease in these aggregate size classes. In the subsequent incubation, the large macroaggregates decreased far more in the samples with CC than in the fallow, leading to similar aggregate size distributions. No difference in C_mic concentration was found among the CC cultivation stages. CO₂ emissions were roughly equivalent to the carbon amounts added as plant residues. Comparison of columns with incorporated or surface‐applied residues indicated no consistent pattern of aggregate distribution, CO₂ emission or C_mic and N_min concentrations. Our results suggest that positive effects of CC cultivation are only short term and that a large amount of organic material in the soil could have a greater influence than CC cultivation.  相似文献   

酸化红薯粉渣对肉兔生长性能、免疫器官指数和胃肠pH的影响     

王中华  毕玉霞  丛付臻 《中国饲料》2012,(11):36-38

为探讨酸化红薯粉渣对肉兔生长性能、免疫器官指数和胃肠pH的影响,试验采用单因子完全随机分组设计,选取128只(公母各半)50日龄体重相近的新西兰兔随机分为4个处理组(对照组、试验1组、2组和3组),每组4个重复,分别饲喂含0%、5%、10%、15%酸化红薯粉渣的饲粮。结果表明,与对照组相比,试验2组和3组肉兔日均采食量、平均日增重、胸腺指数和脾脏指数均显著提高(P<0.05),胃pH显著降低(P<0.05);试验1、2和3组腹泻率、十二指肠pH、盲肠pH均有所降低(P>0.05)。由此可见,在饲料中添加适量的酸化红薯粉渣能提高肉兔的生长性能和免疫器官指数,降低胃肠pH,其中添加量为10%~15%效果较理想。  相似文献