Root zone microbial populations, urease activities, and purification efficiency for a constructed wetland

In order to investigate the effects of microorganisms and their urease activities in macrophytic root zones on pollutant removal, four small-scale plots (SSPs) of vertical/reverse-vertical flow wetlands were set up to determine: a) the relationship between the abundance of microorganisms in the root zones and water purification efficiency; and b) the relationship between urease activities in the root zones and pollutant removal in a constructed wetland system. Total numbers of the microbial population (bacteria, fungi, and actinomyces) along with urease activities in the macrophytic root zones were determined. In addition, the relationships between microbial populations and urease activities as well as the wastewater purification efficiencies of total phosphorus (TP), total Kjeldahl nitrogen (TKN), biochemical oxygen demand in 5 days (BOD₅), and chemical oxygen demand (COD) were also analyzed. The results showed that there was a highly significant positive correlation (r = 0.9772, P < 0.01) between the number of bacteria in the root zones and BOD₅ removal efficiency and a significant negative correlation (r = -0.9092, P < 0.05) between the number of fungi and the removal efficiency of TKN. Meanwhile, there was a significant positive correlation (r = 0.8830, P < 0.05) between urease activities in the root zones and the removal efficiency of TKN. Thus, during wastewater treatment in a constructed wetland system, microorganism and urease activities in the root zones were very important factors.     

条斑紫菜藻红蛋白纯化方法的研究

为了解决目前藻红蛋白纯化方法过于复杂，处理量小等问题，采用“盐析→超滤→HA柱层析或DEAE-52柱层析”的工艺路线，建立了一种简化而高效的条斑紫菜藻红蛋白纯化方法。结果显示：1)对藻红蛋白纯度(以OD₅₆₁/OD₂₈₀表示)为0.365的条斑紫菜粗提物采用盐析法沉淀藻红蛋白时，得到藻红蛋白的纯度为0.45，回收率为90.53%；2)采用截留分子量为5万Da的超滤膜对藻红蛋白盐析物进行脱盐和出去小分子杂蛋白处理，得到的藻红蛋白的纯度为0.74，回收率为93.11%；3)进一步分别采用HA柱层析和DEAE-52柱层析纯化超滤液，藻红蛋白最高纯度分别为2.76和1.74，回收率分别为59.3%和56.81%。研究结果表明，采用盐析和超滤相结合的方法，可以较为方便而高效地得到食用级藻红蛋白，进一步通过HA柱层析，即可达到药用级的要求。     

沙枣果肉原花青素的提取、纯化及抗氧化性能的研究

该文对沙枣果肉中原花青素的提取工艺进行了研究，通过单因素试验，在中心组合试验基础上得出了提取沙枣果肉原花青素的最佳工艺条件：提取温度76℃、提取时间86 min、乙醇浓度72％、提取液pH值5.0、料液比1∶9、提取3次。在此条件下提取率达95.9%。采用固相萃取法对沙枣果肉提取物中原花青素进行纯化，产物纯度为89.91％，原花青素的得率为4.23％；同时对纯化后沙枣果肉原花青素的抗氧化性能进行了测定，结果显示沙枣果肉原花青素有较好的抗脂氧化能力。     

Purification of Raw Surface Water Using Electro-Coagulation Method

The purification of raw surface water from its organic, inorganic and microbial content using the electro-coagulation method was investigated. Batch coagulation experiments were conducted using the jar-test method. A pair of aluminum electrodes (suspended in the jar) was charged with low voltage current for releasing aluminum ions in the raw water to precipitate the suspended matter. The optimum current density was 0.6325 mA cm^–2. The coagulation efficiency was evaluated by determining the turbidity of treated water. The efficiency reduction in raw water turbidity was 90%, leading to a change in water Zeta potential from –85 mV (before treatment) to –40 mV (after treatment), i.e. the particles tended to be destabilized and the coagulation process became predominant. Water contents of nitrates, phosphates and sulfates were considerably reduced by 77.5, 83.3 and 20.0%, respectively. Also, this method is effective in reducing both the total viable bacterial count (TVBC) and total coliforms (TC) by a ratio of 1/10⁴ and 1/10³, respectively.     

银杏黄酮苷提纯工艺研究

根据黄酮苷的物性选择丙酮，正丁醇，正丙醇，乙酸乙酯为萃取剂。单因素实验优选出正丙醇为萃取黄酮苷的主萃取剂。对其进行改性，通过单因素实验和正交实验优化出：水∶正丙醇=1∶25为萃取黄酮苷的较佳萃取剂。T=25℃，t=10 min，固液比=15∶1(g/100 mL)为其最佳萃取工艺参数。最后得到纯度＞50%，得率＞80%的总黄酮苷产品。为后续提纯分离打下较好的基础。     

重组牛IFN-γ蛋白在昆虫杆状病毒表达系统中的表达、纯化和鉴定

为合成与天然构象相似的干扰素γ蛋白,通过优化干扰素序列的密码子序列,利用杆状病毒表达系统合成真核重组牛IFN-γ蛋白。实验化学合成牛IFN-γ基因,并将该基因克隆至真核表达载体pFastBacHTA中,将构建成功的重组载体与DH10Bac感受态大肠杆菌进行转座形成穿梭载体,穿梭载体质粒瞬时转染至SF9昆虫细胞中,获得重组杆状病毒,最后利用SF9昆虫细胞悬浮培养大量表达目的蛋白。蛋白纯化后经Western Blotting和BOVIGAM牛分枝杆菌IFN-γELISA检测试剂盒检测分析,具有较好的免疫原性和反应原性。研究结果为牛IFN-γ的单克隆抗体制备以及牛结核病临床诊断奠定了基础。     

多层楼房式猪舍自动化通风与臭气净化系统的设计与应用

楼房式猪舍因其节约土地、方便管理等突出优点,在越来越多的地方被采用。由于楼房式养殖的饲养密度更大,所以其通风设计与舍外场区环境控制显得尤为重要。文章针对大跨度小单元楼房式猪舍,设计了一种通风与臭气净化相结合的新型通风工艺。夏季采用湿帘-定速风机模式通风降温,保证高效率通风降温;冬季采用檐下通风小窗-吊顶通风窗-变频风机模式,变频风机转速随着氨气浓度上升而相应加大,这种方式可以保证通风效果的同时确保最大程度减少舍内热量损失。在出风端,增加臭气净化处理工艺,利用添加生物菌剂的水循环过滤墙将猪舍排出的臭气通过水洗过滤,降低排出气体中的臭味物质浓度,改善养殖场区空气环境。整套工艺采用智能化控制,实现对系统的精准控制,同时节能降耗,提高养殖场的总体效益。     

富士苹果中膜结合态多酚氧化酶分离纯化方法

以烟台红富士为原料,研究膜结合态多酚氧化酶(m PPO)的分离纯化条件,采用非离子型去污剂结合热诱导方法粗提,硫酸铵分级沉淀,DEAE Sepharose Fast Flow离子交换柱层析方法对m PPO进行纯化,并对其进行串联质谱(LC-MS/MS)分析鉴定。结果表明m PPO提取纯化最佳条件为:超声提取10 min,50%~80%饱和度硫酸铵沉淀,0.1 mol/L Na Cl梯度洗脱。纯化后的m PPO纯度提高了64.30倍,比活力高达387 032.97 U/mg。纯化后的m PPO经SDS-PAGE和Native-PAGE分析均为单一蛋白带,且为亚基分子量67 k Da的二聚体。经串联质谱分析及蛋白数据库鉴定此纯化蛋白为多酚氧化酶。     

沙门氏菌高效价宽谱噬菌体的分离纯化及生物学特性测定

为探索控制沙门氏菌感染的新途径,本试验进行了高效价宽裂解谱噬菌体的分离。首先利用点斑试验和成斑率（EOP）测定法对环境样品进行了沙门氏菌噬菌体的分离纯化及裂解效价和裂解谱的测定,然后对其中1株效价较高、裂解谱较广的噬菌体进行了电镜形态特征观察、最佳感染复数测定、一步生长曲线测定及温度、pH和紫外线敏感性的测定。结果显示,该株噬菌体对不同沙门氏菌的裂解率不同,裂解效价在10⁹~10¹² PFU/mL;对检测的32株沙门氏菌菌株的裂解率为59.4%;透射电镜下观察到该噬菌体为头部直径约70 nm、尾部长约140 nm的长尾噬菌体;以鼠伤寒沙门氏菌ATCC 14028为宿主菌测得最佳感染复数为0.01;在宿主菌鼠伤寒沙门氏菌ATCC 14028中的一步生长曲线显示,潜伏期为20 min,暴发期为100 min,暴发量为113 PFU/cell;在40~60 ℃效价稳定在10¹⁰ PFU/mL,pH 5.0~13.0效价在10⁶ PFU/mL以上,紫外线照射50 min效价仍有10⁶ PFU/mL。综上可知,该株噬菌体分离株具有效价高、裂解谱宽且对温度、pH、紫外线稳定性良好等特性,符合噬菌体制剂的相关特征,具备作为噬菌体制剂后备菌株开发的潜力。     

巴泰病毒G1189aa-239aa肽段的原核表达、纯化及间接ELISA方法的建立

本研究旨在获得高纯度巴泰病毒（Batai virus,BATV） G1蛋白强抗原性肽段,并建立一种用于检测BATV羊血清抗体的间接ELISA方法。首先对G1蛋白51个氨基酸编码的189－239位氨基酸强抗原肽段进行密码子优化,基因合成后构建重组表达质粒pET-32a-G1_189aa-239aa,转化大肠杆菌BL21感受态细胞进行诱导表达。优化表达条件获得大量rHis-G1_189aa-239aa肽段,利用镍柱亲和层析方法进行纯化,并用BCA试剂盒进行蛋白浓度的测定。通过Western blotting对rHis-G1_189aa-239aa肽段进行抗原特异性分析,以rHis-G1_189aa-239aa肽段为抗原,羊BATV阳性血清作为抗体,通过方阵滴定优化反应条件,建立BATV间接ELISA检测方法。SDS-PAGE结果显示,rHis-G1_189aa-239aa肽段在大肠杆菌中主要以包涵体形式存在,分子质量为24.5 ku,在0.1 mmol/L的IPTG诱导5 h后rHis-G1_189aa-239aa肽段表达量达到峰值。通过镍柱亲和层析纯化后,测得蛋白浓度为0.296 mg/mL。Western blotting结果显示,rHis-G1_189aa-239aa肽段特异性较好。以rHis-G1_189aa-239aa肽段为抗原建立的间接ELISA方法,通过条件优化确定最佳抗原包被浓度为2.5 μg/mL,血清和二抗稀释度为1∶60和1∶10 000。样品D_{450 nm}值≥0.367为阳性,D_{450 nm}值≤0.319为阴性。该方法与山羊痘病毒和布鲁氏杆菌的阳性血清均无交叉反应,批内和批间的变异系数均<10%,阳性血清最高可稀释至1 600倍,该方法具有特异性强、灵敏性高和重复性好的特点。利用本方法对云南地区的120份羊血清样本进行检测,血清阳性率为21.67%。本研究获得了特异性强和纯度较高的rHis-G1_189aa-239aa肽段,建立了间接ELISA方法,可应用于羊BATV血清流行病学调查,为疫病防控及致病机制研究奠定基础。