Transfer assessment of carbendazim residues from rapeseed to oil production determined by HPLC–MS/MS

Abstract

It is crucial to develop practical procedures for the control and reduction of pesticide residues in oil productions from farm to dining table. In this study, the dissipation behaviors of typical fungicide from rapeseed to oil production were studied to reveal relationship among spraying stage, application dosage, household oil processing stage, and pesticide residues. In the field trials, rape plants were sprayed with carbendazim at three different dosages during flowering period. Transfer assessment of carbendazim residues from rapeseed to oil production during household oil processing via different press techniques was determined using high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS). The recoveries of carbendazim in rapeseed samples, meals after squeezing samples, and rapeseed oil samples ranged from 82.5% to 93.6% with relative standard deviations (RSDs) ＜5.2%. The validation results illustrated that the methods were reliable and sensitive. The average processing factor (PF) during household oil processing via hot press technique and cold press technique was 0.15 and 0.51, respectively. This study demonstrated that household oil processing could significantly reduce the pesticide residues, especially by hot press technique.     

Cell wall surface layer (S-layer) promotes colony formation in Microcystis: comparison of S-layer characteristics between colonial and unicellular forms of Microcystis and function conformation

Colony is a key to Microcystis becoming a dominant population and forming blooms. To find the mechanism of colony formation, we investigated cell wall structures of colonial and unicellular strains. Results showed that colonial strains had significant surface layer protein (S-layer) on the surface of cells than unicellular strains by transmission electron microscopy. Western blot showed colonial strains had more S-layer than the unicellular strains. When the S-layer gene (GenBank accession number CAO89090.1) of Microcystis aeruginosa PCC7806 was expressed in Synechocystis sp. PCC6803, PCC6803 aggregated into colonial morphology. The results indicated that the S-layer could promote colony formation in Microcystis. Based on the S-layer sequences of PCC6803 and PCC7806, nine S-layer genes in other Microcystis strains were screened from the GenBank. Sequence comparing showed that the S-layers conserved regions were all located in N-terminal. The S-layers contain repeats-in-toxin (RTX) sequences with Ca²⁺-binding site, and their amino acid composition, hydrophobicity, isoelectric point, etc. were consistent with the characteristics of RTX-type S-layer in bacteria.

     

Neurological effects of subchronic exposure to dioctyl phthalate (DOP), lead,and arsenic,individual and mixtures,in immature mice

Environmental Science and Pollution Research - Dioctyl phthalate (DOP) (200, 500, and 1000 mg kg?1 bw, i.g.), Pb (Ac)2 (50 mg L?1, p.o.), and NaAsO2 (10 mg L?1, p.o.) were...     

长江三角洲的区域特点与产业结构

长江三角洲是我国最大的经济核心区，它的发展对于长江流域乃至全国都有重要意义，针对长江三角洲的区域发展特点与产业结构现状进行了分析，找提出了产业结构的调整意见。     

长江中游沿江地区发展冶金工业的资源、条件及对策

长江中游沿江地区有我国第二大钢铁基地─—武钢和国家重要有色基地─—大冶，冶金工业已成为区内的支柱产业，在全国有举足轻重的地位。如何利用现有基础和交通、区位、技术等优势，弥补资源和设备落后等不足，以求更大发展，对区域经济发展和实现“中部崛起”的战略，有着重要的意义。     

固相微萃取及其在环境分析中的应用

本文系统地阐述了一种新型的样品制备方法——固相微萃取的原理及其在环境分析中的应用。该法的优越之处在于可一步完成取样、萃取和浓缩。操作简便、快速且易于实现自动化，适用于挥发性和非挥发性的有机样品的前处理     

从1998年大水看我国未来防洪减灾之路

透视１９９８年南北洪水，通过对自然背景因素，人口因素，防洪工程现状及经济能力限制等的系统分析，指出在今后３０－４０年间，我国防洪事务将面临空前严峻的挑战。     

汽车工业发展中必须解决的环境问题

在可持续发展的大背景下,中国汽车工业发展面临着新的考验。文章从能源短缺,环境影响和城市交通拥堵三方面,探讨了汽车工业发展中必须引起注意、并要努力解决的环境问题。     

Determination of polycyclic aromatic hydrocarbonswith supercritical fluid extractionand chromatography (SFE/SFC )

Ｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｐｏｌｙｃｙｃｌｉｃａｒｏｍａｔｉｃｈｙｄｒｏｃａｒｂｏｎｓｗｉｔｈｓｕｐｅｒｃｒｉｔｉｃａｌｆｌｕｉｄｅｘｔｒａｃｔｉｏｎａｎｄｃｈｒｏｍａｔｏｇｒａｐｈｙ（ＳＦＥ／ＳＦＣ）ＹａｏＷｅｉｘｉ（ＲｅｓｅａｒｃｈＣｅｎｔｅ...     

季戊四醇酯的生物降解评估研究

根据用评估润滑油生物降解性的CEC测试方法，对新型冷冻机的润滑油基础油季戊四醇酯的生物降解性以及添加剂对其的影响进行评估，并结合红外光谱讨论季戊四醇酯的生物降解规律。