RETRACTED ARTICLE: The bioremediation of metolachlor in soil using Rhodospirillum rubrum after wastewater treatment

Purpose

Reliable and effective techniques for removing contaminants from soil are highly desirable. However, metolachlor residue bioremediation and soil fertility improvement by Rhodospirillum rubrum (R. rubrum) in effluent after wastewater treatment have not yet been investigated. The aims of this study were to investigate the feasibility of bioremediation of metolachlor residues in soil and soil fertility improvement by R. rubrum in effluent and to explain the mechanism that R. rubrum in effluent was induced to express the regulatory gene.

Materials and methods

Soybean processing wastewater was obtained from Harbin Soybean Products Machining Factory. Soil samples were the surface soil (0–30 cm) from campus (1.77 g/kg total N, 4.15 g/kg total P, 1.58 g/kg total K, 17 g/kg SOM, 0.07 g/kg SMBC). Cytochrome P450 monooxygenase regulatory gene, MAPKKKs gene, was measured by RT-PCR.

Results and discussion

Compared to control treatment, metolachlor was removed efficiently and soil fertility was remediated by effluent containing R. rubrum. The removal in concentrations reached 2.97 mg/L (99%). Soil organic matter (SOM) and SMBC were enhanced 42 times. Molecular analysis revealed that metolachlor induced cpm gene expression to synthesize cytochrome P450 monooxygenase through activating MAPKKKs gene in MAPK signal transduction pathway.

Conclusions

Bioremediation of metolachlor in soil and improvement of soil fertility using R. rubrum in effluent were feasible. Metolachlor, as environmental pressure, induced cpm gene expression to synthesize cytochrome P450 monooxygenase and to remove metolachlor through activating MAPKKKs, MAPKKs, MAPKs genes in MAPK signal transduction pathway.

     

3种水质调控方式下刺参池塘初级生产力的周年变化

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通过对晋中地区毛白杨、新疆杨、北京杨这3种树种实地调查和资料收集,得出：早春时期,重点应从树皮的颜色与粗糙度、皮孔的形状、大小及密集度来鉴别树种。通过对树高、胸径、成活率等的实地测量及内业计算,在树种选择上应优先选择新疆杨和毛白杨。在今后的通道绿化及城市绿化中,可以根据绿化的成本及成效要求灵活选择规格。     

负压轻炭化木材物理力学性能

对比了奥克榄Aucoumea klaineana,椴木Tilia europaea,单瓣豆Monopetalanthus sp.等3种木材在同一炭化条件下物理力学性能的变化,探究负压轻炭化处理木材的可行性与实际效果。将3种木材分别置于真空炭化箱内以160℃,0 MPa的条件处理3.0 h,然后将木材按照国标规定的木材物理力学试材锯解及试样截取方法加工,之后分别测量木材的密度、色差、冲击韧性、抗弯强度、抗弯弹性模量、硬度、干缩率和湿胀率。结果表明:在该炭化工艺下单瓣豆的体积干缩系数降低了16.00%,尺寸稳定性有较大改善;抗弯强度增加了18.00%,径面、弦面和端面硬度分别增加了19.00%,33.00%和50.00%,冲击韧性损失24.00%。负压轻炭化能够在一定程度上改善木材的尺寸稳定性,并且使其物理力学性能不受太大损失。     

绵羊及相关物种去乙酰化酶1的理化性质和蛋白结构预测

为深入研究SIRT1基因及其编码蛋白的结构和功能,特别是在各信号通路中的作用,本文基于NCBI发布的包括绵羊在内的9个物种的SIRT1基因的核苷酸和蛋白质序列,采用生物信息学方法分析SIRT1蛋白的理化性质和蛋白结构,预测了绵羊SIRT1蛋白的结构和翻译后修饰位点。结果表明,不同物种SIRT1蛋白的理化性质基本一致。绵羊SIRT1是一种接近于中性的亲水性脂溶蛋白,预测其有40个潜在的O-糖基化位点、2个N-糖基化位点、33个磷酸化位点、18个乙酰化修饰位点、11个泛素化修饰位点和3个类泛素化修饰位点。这些结果为进一步研究SIRT1的功能和表达调控奠定了科学依据。     

添加剂对青贮水稻秸秆发酵品质的改善作用

水稻种植产生大量的作物残渣,其中只有20%用于工业和生活用途。在大多数发展中国家(特别是东南亚),水稻秸秆常常被用作反刍动物的饲料原料。但由于其蛋白质含量低,木质素和二氧化硅含量高,消化率和营养价值受到限制。青贮可以提高水稻秸秆的营养价值,促进其合理利用。影响青贮饲料质量的因素主要包括水溶性碳水化合物、微生物菌群和原料的收获条件。饲料添加剂可以控制发酵过程,提高青贮饲料的营养成分和稳定性。本文综述了青贮饲料加工的一些实际问题,以及利用添加剂提高水稻秸秆发酵质量。     

The removal of butachlor from soil by wastewater-derived Rhodopseudomonas marshes

Butachlor is a systemic selective pre-emergent herbicide most commonly used to control grasses and broadleaf weeds. Residual butachlor in soil can have harmful ecotoxological effects and remediation is, therefore, important. Effects of Rhodopseudomonas marshes in wastewater effluent on biorestoration of butachlor in soil were investigated. Over a time period of one day, butachlor induced EthB gene expression to synthesize cytochrome P450 monooxygenase which led to the successful bioremediation of the herbicide. Residual organics in wastewater effluent provided sufficient carbon sources for continued growth of R. marshes beyond one day.     

SIRT1基因在绵羊不同组织器官中的差异性表达研究

SIRT1(silent mating type information regulation 2homolog1)是一种具有NAD+依赖性去乙酰化酶活性的转录调节因子,参与能量代谢的调节。利用实时荧光定量PCR技术,对10月龄山西肉用绵羊母本品系去势公羊内脏(肝、肾、脾、肺、心)、肌肉(背最长肌)和脂肪(大网膜、小网膜、肠系膜、腹膜后、皮下)等11种器官或组织中SIRT1基因mRNA的表达量进行检测,以探讨SIRT1基因的差异性表达规律。结果表明,绵羊SIRT1基因在所检测的器官或组织中均有表达,且差异极显著(P0.001)。主要表现在脾脏、肝脏和肾脏中的表达显著高于心脏和肺脏中的表达;深层脂肪组织中的表达高于浅层的皮下脂肪;在背最长肌中也有较高表达。这些差异与绵羊SIRT1基因调节脂质代谢及糖异生有关。有关结果为研究SIRT1基因的功能奠定了科学依据。