Selective separation of deltamethrin by molecularly imprinted polymers using a β-cyclodextrin derivative as the functional monomer

A deltamethrin-imprinted polymer (MIP₁) was prepared using bis(-6-O-butanediacid monoester)-β-cyclodextrin (BBA-β-CD) as the functional monomer and toluene 2,4-diisocyanate (TDI) as the cross-linker. In comparison to the molecularly imprinted polymer where β-CD was applied as the functional monomer (MIP₂), MIP₁ showed a higher specific binding capacity (ΔC_P) and an improved imprinting factor (IF) for deltamethrin. The selective recognition experiments demonstrated that compared to MIP₂, MIP₁ could better recognize its template over other substrates that had similar chemical structures. The solid phase extraction (SPE) of deltamethrin using MIP₁ as the adsorbent was further investigated. The recoveries of the molecularly imprinted solid phase extraction (MISPE) column for deltamethrin were 83.2–93.4% with relative standard deviations (RSD) of 2.03–6.19%. The method has been successfully applied to the enrichment of trace deltamethrin from real water samples.     

Sorption of 1-naphthol by plant cuticular fractions

The contribution of aliphatic-rich plant biopolymer to sorption of hydrophobic organic compounds is significantly important because of their preservation and accumulation in the soil environment,but sorption mechanism is still not fully understood.In this study, sorption of 1-naphthol by plant cuticular fractions was examined to better understand the contributions of respective fraction.Toward this end,cuticular materials were isolated from the fruits of tomato by chemical method.The tomato cuticle sheet consisted of waxes (6.5 wt%),cuticular monomer (69.5 wt%),and polysaccharide (24.0 wt%).Isotherms of l-naphthol to the cuticular fractions were nonlinear (N value (0.82-0.90)) at the whole tested concentration ranges.The KodKow ratios for bulk cuticle (TC1),dewaxed cuticle (TC2),cutin (TC4),and desugared cuticle (TC5) were larger than unity,suggested that tomato bulk cuticle and cutin are much powerful solption medium.Sorption capability of cutin (TC4) was 2.4 times higher than the nonsaponifiable fraction (TC3).The 1-naphthol interactions with tomato cuticular materials were governed by both hydrophobic-type interactions and polar (H-bonding) interactions. Removal of the wax and polysaccharide materials from the bulk tomato cuticle caused a significant increase in the sorption ability of the cuticular material.There was a linear negative trend between K_(oc) values and the amount of polysaccharides or fraction's polarities ((N O)/C);while a linear positive relationship between K_(oc) values and the content of cutin monomer (linear R~2=0.993) was observed for present in the cuticular fractions.Predominant sorbent of the hydrophobic organic compounds (HOCs) in the plant cuticular fraction was the cutin monomer,contributing to 91.7% of the total sorption of tomato bulk cuticle.     

Effect of Agricultural Antibiotics on the Persistence and Transformation of 17β-Estradiol in a Sequatchie Loam

A laboratory incubation study was conducted to investigate the effect of agricultural antibiotics (sulfamethazine, tylosin, and chlortetracycline) on the persistence and transformation of 17β-estradiol in Sequatchie loam. We measured concentrations of 17β-estradiol and its primary metabolite (estrone) in soils spiked with antibiotics and 17β-estradiol. Dehydrogenase activity (DHA) was also measured as an indicator of the total microbial activity of the soils. The presence of antibiotics significantly decreased transformation of 17β-estradiol to estrone. There was a positive correlation between the DHA and the concentrations of estrone in soil spiked with 17β-estradiol only, implying that the reaction is mainly catalyzed by dehydrogenases. However, the positive correlation was weakened in soil spiked with 17β-estradiol and antibiotics together. We recommend that any study evaluating the fate and transport of estrogenic hormones in soil should include the effect of agricultural antibiotics because antibiotics and estrogenic hormones are commonly excreted together in environmental samples.     

NLRP3 inflammasome activation determines the fibrogenic potential of PM2.5 air pollution particles in the lung

Airborne fine particulate matter(PM_2.5) is known to cause respiratory inflammation such as chronic obstructive pulmonary disease and lung fibrosis. NLRP3 inflammasome activation has been implicated in these diseases; however, due to the complexity in PM_2.5compositions, it is difficult to differentiate the roles of the components in triggering this pathway. We collected eight real-life PM_2.5samples for a comparative analysis of their effects on NLRP3 inflammasome ...     

17β3-雌二醇对西伯利亚鲟幼鱼的雌激素效应

为了研究以及评估在利用17β-雌二醇(estradiol-17β,E2)混饲投喂进行人工诱导西伯利亚鲟(Acipenser baerii)性别逆转过程中,外源雌激素处理对西伯利亚鲟幼鱼的雌激素效应以及激素残留风险.实验选取健康的2月龄西伯利亚鲟840尾,设置E2在饲料中的投喂剂量为1 mg·1kg-1(C组)和10 m...     

Antioxidant contents of bell pepper and melon fruits grown in soil amended with recycled waste

Composting and land application of municipal sewage sludge (SS) and yard waste (YW) compost are increasingly popular ways for using organic waste as a source of organic matter, while decreasing the amount of waste being diverted into landfills. Researchers have largely ignored the effect of SS and SS mixed with YW (SS+YW) compost on the antioxidant contents of vegetables grown under this practice. Accordingly, the main objective of this investigation was to monitor the impact of SS and SS+YW on the nutritional composition of pepper and melon fruits at harvest. Total phenols and ascorbic acid contents of pepper and melons (determined by the Folin-Ciocalteau and the dichlorophenol–indophenol methods, respectively) were greater in pepper than melon fruits. Soil amended with SS or SS+YW significantly elevated the concentrations of ascorbic acid and total phenols in melon fruits compared to no-mulch native soil. The application of SS did not modify the concentration of β-carotene in melon fruits at three harvests. Regardless of soil treatments, ascorbic acid and total phenols concentrations were greater in melon fruits collected at the first harvest compared to harvest three. Pepper fruits collected at harvest three contained the greatest concentrations of ascorbic acid and total phenols; whereas, pepper fruits collected at the second harvest contained the greatest concentrations of soluble sugars.     

环境浓度下磺胺混合物对秀丽线虫(Caenorhabditis elegans)生长、饮食、抗氧化酶及其调控基因表达水平的影响

磺胺类药物在环境中的普遍残留引起了人们对其潜在效应的担忧。因为磺胺混合物的效应不能通过单个物质效应进行准确预测,所以需要针对混合物效应开展深入研究。将秀丽线虫暴露于4种常用磺胺药物(磺胺嘧啶、磺胺吡啶、磺胺甲噁唑和磺胺甲嘧啶)组成的、环境浓度水平(0.01 mg·L-1)的混合物后,对生长调控基因dbl-1和egl-4,饮食调控基因eat-2和eat-18,过氧化氢酶(CAT)编码基因ctl-2和ctl-3,寿命调控基因sir-2,以及凋亡调控基因ced-4的表达水平进行检测。暴露组与空白对照组的结果比较表明,秀丽线虫dbl-1表达水平没有显著变化(下调3%),egl-4表达下调18%,解释了生长的抑制效应(抑制率为15.6%)。eat-2和eat-18的表达水平下调幅度相似,介于20%~22%之间,该幅度高于饮食的抑制效应(10.7%)。ctl-2和ctl-3的表达水平上调,分别比空白对照组高101%与66%,该幅度显著小于0.01 mg·L-1磺胺混合物暴露对CAT活性的刺激效应(比空白对照组高789.5%)。此外,sir-2的表达水平没有显著变化,与线虫寿命没有受到显著影响相一致。同时,ced-4表达上调32%,预示凋亡水平的显著增加。egl-4、eat-2、ctl-2和ced-4基因表达水平的显著变化分别表明磺胺混合物对β转化生长因子(TGF-β),烟酰乙酰胆碱受体(n AChR)、抗氧化系统以及细胞凋亡等多个方面的产生影响。