Microbiological Quality of Cyperus esculentus L. Products Sold in Ouagadougou and Bobo Dioulasso (Burkina Faso)

This study aimed to assess the microbiological quality of tiger nut (Cyperus esculentus L.) products sold in Ouagadougou and Bobo Dioulasso. The microbial load of tubers and tiger nut milk was determined using ISO 4833-1 (2003) standard (total mesophilic aerobic flora), NF ISO 7954 (1998) standard (yeasts and molds), and ISO 4832 (2006) standard (total coliforms, thermotolerant coliforms). The results showed that tiger nut tubers had an average microbial load between 4.86 ± 7.03 × 106 UFC/g and 1.82 ± 2.30 × 107 UFC/g for total mesophilic aerobic flora, from 4.34 ± 10.6 × 105 UFC/g to 3.52 ± 4.54 × 106 UFC/g for yeasts and molds, from 2.23 ± 2.25 × 105 UFC/g to 1.41 ± 2.16 × 105 UFC/g for total coliforms and from 1.83 ± 2.03 × 105 UFC/g to 7.0 ± 10.8 × 104 CFU/g for thermotolerant coliforms. For tiger nut milk samples, the average microbial load varied from 3.48 ± 2.98 × 106 CFU/g to 2.80 ± 5.69 × 107 CFU/g for total mesophilic aerobic flora, from 5.00 ± 7.21 × 104 CFU/g to 1.88 ± 3.31 × 105 CFU/g for yeasts and molds, from 4.58 ± 10.4 × 104 CFU/g to 6.31 ± 9.17 × 105 CFU/g for total coliforms and 7.00 ± 7.00 × 103 CFU/g to 2.87 ± 5.86 × 105 CFU/g for thermotolerant coliforms. This study revealed that the tubers and tiger nut milk sold in Ouagadougou and Bobo Dioulasso had a high microbial load which could lead to the degradation of these products and food poisoning for consumers.

Neuroprotection of Cyperus esculentus L. orientin against cerebral ischemia/reperfusion induced brain injury

Orientin is a flavonoid monomer.In recent years,its importance as a source of pharmacological active substance is growing rapidly due to its properties such as anti-myocardial ischemia,anti-apoptosis,anti-radiation,anti-tumor,and anti-aging.However,the neuroprotective effects of Orientin on stroke injury have not been comprehensively evaluated.The aim of the present study was thus to investigate the neuroprotective capacity and the potential mechanisms of Cyperus esculentus L.orientin(CLO)from Cyperus esculentus L.leaves against ischemia/reperfusion(I/R)injury using standard orientin as control.For in vitro studies,we treated HT22 cells with CoCl2 as an in vitro ischemic injury model.HT22 cells in the control group were treated with CoCl2.For in vivo studies,we used rat models of middle cerebral artery occlusion,and animals that received sham surgery were used as controls.We found that CLO protected CoCl2-induced HT22 cells against ischemia/reperfusion injury by lowering lipid peroxidation and reactive oxygen species formation as well as decreasing protein oxidation.However,CLO did not reduce the release of lactate dehydrogenase nor increase the activity of superoxide dismutase.Results showed that CLO could decrease neurological deficit score,attenuate brain water content,and reduce cerebral infarct volume,leading to neuroprotection during cerebral ischemia-reperfusion injury.Our studies indicate that CLO flavonoids can be taken as a natural antioxidant and bacteriostastic substance in food and pharmaceutical industry.The molecular mechanisms of CLO could be at least partially attributed to the antioxidant properties and subsequently inhibiting activation of casepase-3.All experimental procedures and protocols were approved on May 16,2016 by the Experimental Animal Ethics Committee of Xinjiang Medical University of China(approval No.IACUC20160516-57).

不同除草剂对棉田恶性杂草香附子的防除效果及安全性分析

为筛选出棉田防除香附子(Cyperus rotundus L.)的除草剂,选用5种除草剂,采用大田试验,对比分析了其对棉田香附子的防治效果及对棉花生长的安全性。结果表明,药后14 d,75%氯吡嘧磺隆水分散粒剂(WG)和10%吡嘧磺隆可湿性粉剂(WP)对香附子的株防效分别为88.68%和87.71%,极显著高于其他药剂处理;药后21 d,75%氯吡嘧磺隆WG和10%吡嘧磺隆WP对香附子的株防效分别为78.70%和76.04%,极显著高于其他药剂处理;药后28 d,75%氯吡嘧磺隆WG对香附子的株防效和鲜重防效分别为82.37%和91.82%,极显著高于其他药剂处理;安全性分析显示,5种除草剂均对棉花生长安全。

几种湿地植物对重金属镉胁迫的生理生化响应

通过水培试验研究了不同质最浓度的重金属镉（0、20、30、40、50、60mg·L^-1）胁迫对水牛美人蕉（Canna glauca）、红蛋（Eehinodorus osiris）、风车草（Cyperus alternifolius）、彩叶草（Coleus blumeibenth）等湿地植物体内丙二醛、脯氨酸、镉的含量以及细胞膜的透性变化的影响，探讨了镉胁迫下不同湿地植物对镉的生理生化响应和耐受能力，为应用人工湿地处理含镉废水提供依据。研究结果表明，在镉胁迫下4种供试植物叶片的丙二醛含量和膜透性增加，并且试验条件下，培养液中镉质量浓度越高植物叶片中丙二醛细胞膜透性也越高；植物叶片中脯氨酸质量分数变化则有所不同，培养液中镉质量浓度处于0-40mg·L^-1时，脯氨酸质量分数随着镉质量浓度增加而增加，镉质量浓度高于40mg·L^-1，脯氨酸质量分数随着镉质量浓度的增加而降低。不同湿地植物对镉胁迫响应也显著不同，丙二醛含量、脯氨酸质量分数和细胞膜透性大小为：彩叶草〉风车草〉红蛋〉美人蕉。由此可见，4种供试植物耐受镉害的能力依次为：美人蕉〉红蛋〉风车草〉彩叶草。美人蕉和红蛋在含镉废水人工湿地生态工程修复中具有很好的应用前景。

湿生植物根系泌氧能力与其结构相关性研究

为了更好地了解湿生植物对湿地基质供氧能力,对西伯利亚鸢尾、风车草、芦竹和腺柳根系泌氧能力进行研究,并计算湿地植物泌氧能力,为人工湿地不同植物选择提供参考数据。结果表明:在26℃、3000 lux光照的水培条件下,芦竹根系干重泌氧率最高,达到0.201 mmol/(g·h)。湿生植物植株干重泌氧速率与根重-根长比及植株-根系干重比呈显著正相关(p<0.01),也与根系孔隙度呈显著正相关。除木本植物腺柳外,西伯利亚鸢尾、风车草和芦竹单植株干重的泌氧率与通气组织面积占比呈显著正相关(p<0.01),而与根系表皮层平均厚度呈显著负相关(p<0.01),因此,通气组织发育程度和根系表皮层厚度也是影响湿生植物根系泌氧能力的重要因素。基于试验条件,湿地芦竹泌氧率为38.4 g/(m^2·d),湿地腺柳泌氧率为98.3 g/(m^2·d),都高于西伯利亚鸢尾和风车草泌氧率。因此,腺柳和芦竹有利于提高湿地基质中氧含量,其根际易于形成好氧环境。

风车草对低污染水体氮磷的净化效能

为探讨湿地水生植物对低污染水体中氮磷的去除效果,以挺水植物风车草为研究对象,研究其对低污染水中氮、磷削减的日变化规律,及温度对净化效果的影响,并探究了系统中溶解性有机物的变化。结果表明:风车草对低污染水的氮、磷去除过程符合一级动力学方程,常温下(24~30℃)对TN、TP去除的一阶反应速率常数分别为0.4493、0.5028,70 h后对TN、TP的去除率高达82.87%、72.40%,日变化率分别为48.52%、40.31%,而低温(4~8℃)下风车草对氮、磷的去除效果明显受到抑制且根系活力显著降低;系统中溶解性有机物组分(紫外类腐植酸和类色氨酸)含量随时间延长而增加,相关性分析表明二者均利于水中氮磷的去除。研究表明,风车草对低污染水体中氮磷具有较好的净化效果,且其净化效能受温度的影响。

异型莎草对不同除草剂的敏感性研究

采用盆栽法茎叶处理方式分别测定了湖南省4个地区的水田异型莎草(Cyperus difformis L.)对灭草松、二甲四氯、吡嘧磺隆、氯吡嘧磺隆、五氟磺草胺5种除草剂的敏感性。结果表明,各异型莎草种群对灭草松和二甲四氯均敏感,鲜重抑制率达90%以上;种群H1、H4对氯吡嘧磺隆不敏感,鲜重抑制率最高达32.12%;种群H1、H3、H4对吡嘧磺隆产生抗性,其ED50分别为6 397.17、194.18、198.06 g(a.i.)/hm2,且这3个种群对五氟磺草胺产生交互抗性,但种群H2对吡嘧磺隆和五氟磺草胺均敏感。

Treating wastewater under zero waste principle using wetland mesocosms

The present investigation demonstrates the synergistic action of using a sedimentation unit together with Cyperus papyrus(L.)wetland enriched with zeolite mineral in one-year round experiment for treating wastewater.The system was designed to support a horizontal surface flow pattern and showed satisfactory removal efficiencies for both physicochemical and bacteriological contaminants within 3 days of residence time.The removal efficiencies ranged between 76.3%and 98.8%for total suspended solids,turbidity,iron,biological oxygen demand,and ammonia.The bacterial indicators(total and fecal coliforms,as well as fecal streptococci)and the potential pathogens(Escherichia coli,Staphylococcus aureus,and Pseudomonas aeruginosa)showed removal efficiencies ranged between 96.9%and 99.8%.We expect the system to offer a smart management for every component according to zero waste principle.The treated effluent was reused to irrigate the landscape of pilot area,and the excess sludge was recycled as fertilizer and soil conditioner.The zeolite mineral did not require regeneration for almost 36 weeks of operation,and enhanced the density of shoots(14.11%)and the height of shoots(15.88%).The harvested plant biomass could be a profitable resource for potent antibacterial and antioxidant bioactive compounds.This could certainly offset part of the operation and maintenance costs and optimize the system implementation feasibility.Although the experiment was designed under local conditions,its results could provide insights to upgrade and optimize the performance of other analogous large-scale constructed wetlands.

葡萄糖碳源对复合垂直流人工湿地甲烷排放的驱动影响

人工湿地甲烷排放驱动对全球变暖具有重要作用,为控制甲烷排放同时提高污水去除效率,构建了5层不同介质组成的复合垂直流人工湿地系统(Integrated Vertical-Flow Constructed Wetland,IVCW),利用现场监测和动力学模型分析添加不同浓度葡萄糖碳源对甲烷排放驱动和总氮(TN)、化学需氧量(COD)去除率的影响.结果表明:添加0.5、1、2和4 mmol/L葡萄糖溶液时,(1)甲烷排放通量分别为4、3.50、3.90和3.40 mol m^(-2) d^(-1),比空白实验分别增加了27%、12%、24%和9.80%;(2)对应的风车草茎叶系统甲烷排放通量比根水系统分别高了0.90、1.60、1.50和0.70 mol m^(-2)d^(-1);(3)同时IVCW对碳平均利用率分别为32.17%、53.51%、76.86%和76.72%;TN平均去除率分别为37.30%、11.14%、14.79%和48.75%,COD平均去除率分别为70%、91.10%、98.78%和92.31%.(4)葡萄糖驱动IVCW甲烷排放可认为符合二级动力学方程,其甲烷驱动常数为49.64 mg/h.本研究结果表明添加葡萄糖驱动IVCW的甲烷排放处于较高水平,甲烷平均排放通量增加了18.2%,可为IVCW处理污水过程中甲烷排放提供参考.