替考拉宁产生菌醋酸钠抗性变株的选育

为选育替考拉宁高产菌种，提高替考拉宁发酵单位，采用替考拉宁产生菌（Actinoplanes teichomyceticus）经紫外诱变后筛选链霉素抗性。获得了替考拉宁高产变株04-10-3，其发酵单位比出发菌株XYU-28提高55％。传代试验表明菌株04-10-3的遗传特性较稳定。     

不同氨基酸和植物油对替考拉宁产量及组分含量的影响

研究了氨基酸和植物油对替考拉宁产量和组分含量的影响。结果发现,与对照相比,在发酵培养基中添加0.05%异亮氨酸和0.05%L-缬氨酸,替考拉宁产量分别提高24.7%和38.2%;在发酵培养基中添加0.50%大豆油和0.50%玉米油,替考拉宁产量分别提高20.4%和28.7%。L-缬氨酸和大豆油在提高替考拉宁产量的同时,对主成分A2-2的影响作用是相反的,L-缬氨酸可以升高A2-2含量,而大豆油则降低A2-2含量。L-缬氨酸和大豆油的联合使用可进一步提高替考拉宁产量,当L-缬氨酸和大豆油添加量分别为0.06%、0.75%时,替考拉宁产量提高47.2%。优化后的配方经过50L发酵罐发酵验证,替考拉宁的平均发酵效价达到5 652U·mL~(-1),各组分含量均符合质量要求,主成分A2-2含量达到53.1%。     

高效液相色谱法检测替考拉宁组分及其有关物质

建立了替考拉宁组分及其有关物质的HPLC测定方法.色谱柱为Agilent Extend-C18柱(5 μm,4.6mm×25 0 mm),流动相为20mmol/L醋酸铵-乙腈,梯度洗脱,柱温30℃,检测波长254 nm.该方法对替考拉宁的5种主要组分及其有关物质能够较好地分离.该方法稳定、准确,可用于替考拉宁及其有关物质的测定.     

头孢菌素C产生菌的诱变育种及发酵应用

以头孢菌素C产生菌顶头孢霉(Cephalosporium acremonium)B-1822-S-04为出发菌株,经过紫外线和丙二酸复合诱变,筛选得到了4株头孢菌素C高产菌株D-G-017、D-G-083、D-G-096和D-G-133,其中菌株D-G-096的效价高达6 816 mg·L~(-1),较出发菌株提高了50.80%,且高产特性稳定;50 L发酵罐小试结果显示,菌株D-G-096的效价达到了29 270 mg·L~(-1),较出发菌株提高了111.06%,可作为优良高产菌株保存使用。该实验筛选出的高产菌株及其在小试中的应用,可为后期工业化生产提供优质菌种资源,为发酵工艺提供指导。     

替考拉宁提取工艺研究

替考拉宁由于是多组分抗生素,工业分离时容易因为各组分回收率差异大而使产品质量比原研药Targocid(他格适)差。通过研究开发了一种新的提取工艺,能同时有效提取替考拉宁的各组分。以替考拉宁发酵液为原料,通过微滤、两次层析、脱色、结晶、过滤、干燥等步骤,所得到的替考拉宁能同时满足EP、JP和CP的质量要求,与Targocid(他格适)质量接近。     

替考拉宁吸附树脂的筛选

替考拉宁为游动放线菌属发酵产生的糖肽类抗生素,发酵液中含有大量的色素、无机盐、杂蛋白以及同系物等杂质.介绍了替考拉宁富集树脂型号和类型的筛选以及发酵液pH值的筛选.     

复合诱变法筛选FK506高产菌株

通过复合诱变的方法对出发菌株筑波链霉菌08-6—9进行处理,得到一株FK506高产菌株08-9-81,其摇瓶发酵水平较出发菌株提高73．6％,并顺利通过20L发酵罐放大,具有实际生产意义。     

恩拉霉素高产菌株的筛选

从原始生产菌BKSFJ06出发,对其进行了紫外诱变、氯化锂与紫外复合诱变、亚硝基胍诱变和亚硝基胍与紫外的复合诱变及恩拉霉素抗性筛选工作,用HPLC检测方法,以恩拉霉素的产量为指标,筛选高产菌株。最终筛选出的最优突变菌株ERS42-101108产量提高了50%,且该菌株具有良好的遗传稳定性。通过实验内容可以看出,通过亚硝基胍和紫外复合诱变的方法,抗自身产物定向筛选出的突变株具有较优良的性质。     

利用前体物质定向选育阿维菌素高产菌株

以除虫链霉菌(Streptomyces avermitilis)AV-0105为出发菌株,采用紫外线诱变处理,并结合前体抗性定向选育阿维菌素高产菌株. 通过对致死率的考察,确定了紫外线诱变的最适剂量. 在分离培养基中分别加入不同体积分数的缬氨酸和D -脱氧葡萄糖作为前体物质进行正突变株的定向筛选,选育得到阿维菌素高产菌株 AV-03-35,其摇瓶发酵效价达到4 695 u/mL,较出发菌株提高15.5%. 采用该菌株在2 t罐进行生产验证,平均发酵效价达4 592 u/mL,较出发菌株提高了13%.     

采用紫外线和微波处理法选育万古霉素高产菌株

以东方拟无枝酸菌（Amycolatopsisoriental）V30为出发菌株,经过紫外线、微波复合诱变,选育得到万古霉素高产菌株V311-04,较出发菌摇瓶单位提高7%以上,并且有良好的遗传稳定性。     

卡泊芬净合成前体Pneumocandin B0的发酵工艺研究

以Pneumocandin B0 PB5—31为出发菌株,从筛选高产菌株和提高产物中有效组分的比例两方面进行研究,以期提高Pneumocandin B0的发酵水平。结果表明,紫外线诱变复合氯化锂后处理筛选出高产菌株,其发酵效价比出发菌株提高了72％;发酵培养基中添加0．3％的脯氨酸很好地提高了有效组分B0的比例。     

拟无枝菌酸菌M3-1降解丙酯草醚的特性及应用初探

丙酯草醚是我国自主研制的一种新型高效油菜田除草剂。采用现代分子生物技术和微生物学传统方法从长期施用嘧啶水杨酸类除草剂的农田中富集、筛选出以丙酯草醚为唯一碳源生长的高效降解菌株M3-1,并对其最适降解条件及在土壤中的应用进行研究。结果表明:(1)经形态、生理生化和16S rDNA鉴定,M3-1属于拟无枝菌酸菌(Amycolatopsis sp.)。(2)最适温度为35℃,pH为6.0,接种量为8%,在底物(ZJ0273)浓度为100～400 mg.L.1均具有一定的降解效果,且降解率随底物浓度的增加而降低,浓度高于300 mg.L.1时,对M3-1的降解效果有较强的抑制作用。(3)最适降解条件下,水溶液中培养25 d对浓度为100 mg.L.1丙酯草醚的降解率可达63.3%。(4)M3-1在土壤中对ZJ0273有很好的去除效果,处理25 d,其降解率可达53.7%。     

卡泊芬净合成前体Pneumocandin Bo的发酵工艺研究

以Pneumocandin B0 PB5-31为出发菌株,从筛选高产菌株和提高产物中有效组分的比例两方面进行研究,以期提高Pneumocandin B0 的发酵水平.结果表明,紫外线诱变复合氯化锂后处理筛选出高产菌株,其发酵效价比出发菌株提高了72％;发酵培养基中添加0.3％的脯氨酸很好地提高了有效组分B0的比例.     

Adsorptive removal of tetracycline from water using Fe (III)-functionalized carbonized humic acid

Humic acid (HA) was carbonized at 300, 400 and 500 ℃ and then functionalized with 1 wt%-12 wt% Fe(III) respectively [CHA300/400/500-Fe(III)]. Adsorption of such Fe(III)-functionalized carbonized HA as adsorbents to aqueous tetracycline (TC: 25 mg·L^-1) was studied. The adsorption equilibrium time for CHA400-Fe(III) to TC was 6 h faster and the adsorption removal efficiency (R_e) was two times higher than that of HA/CHA. The adsorption R e of CHA400-Fe(III) loaded 10% iron [CHA400-(10%)Fe(III)] to TC could reach 99.8% at 8 h and still kept 80.6% after 8 cycles. The adsorption kinetics were well fitted to the pseudo-second-order equation and the adsorption isotherms could be well delineated via Langmuir equations(R² > 0.99), indicating that the homogeneous chemical adsorption of TC occurred on the adsorbents. The main adsorption mechanisms of TC were complexation Fe(III) and hydrophobic distribution. Electropositive and electronegative repulsion between TC and CHA400-(10%)Fe(III) at lowly pH(2) and highly pH(8-10) respectively, leaded to the relatively low adsorption capacity and more notable influence of ion concentration. When the pH was between 4 and 8, TC mainly existed in neutral molecules (TCH₂), so the influence of ion concentration was not obvious. The dynamic adsorption results showed that the CHA400-(10%)Fe(III) could continuously treat about 2.4 L TC(27 mg·L^-1) wastewater with the effluent concentration as low as 0.068 mg·L^-1. Our study suggested a broad application prospect of a new, effective, lowcost and environment-friendly adsorbent CHA400-(10%)Fe(III) for treatment of low-concentration TC polluted wastewater.     

重组痘苗病毒VMS11HAV25株的毒力研究

对带有甲肝病毒抗原基因的重组痘苗病毒VMS11HAV25株与其亲本病毒天坛株和JingC－1系减毒株进行了毒力比较，结果表明，VMS11HAV25株对小鼠神经毒力和尾静脉注射后的全身症状以及家兔皮内反应都比天坛株有明显减弱。在40℃培育下鸡胚尿囊膜（CAM）上形成的痘疱数也比天坛株有明显减少。VMS11HAV25株在37℃培育下CAM上形成的痘疱较大，家兔皮内接种后出现有小面积的皮肤坏死性损伤，因此认为，VMS11HAV25株的残余毒力高于JingC－系，介于天坛株和JingC－1系减毒株之间。     

Characterization of Thermophilic Halotolerant Aeribacillus pallidus TD1 from Tao Dam Hot Spring, Thailand

The bacterial strain TD1 was isolated from Tao Dam hot spring in Thailand. Strain TD1 was Gram positive, rod-shaped, aerobic, motile, and endospore forming. The cell was 2.0-40 μm in length and about 0.4 μm in diameter. The optimum growth occurred at 55-60 °C and at pH 7-8. Strain TD1 was able to grow on medium containing up to 10% NaCl. The DNA G+C content was 38.9 mol%. The cellular fatty acid content was mainly C(16:0), which comprised 25.04% of the total amount of cellular fatty acid. 16S rDNA showed 99% identity to Aeribacillus pallidus DSM 3670(T). Bayesian tree analysis strongly supported the idea that strain TD1 is affiliated with genus Aeribacillus, as Aeribacillus pallidus strain TD1. Although the 16S rDNA of A. pallidus strain TD1 is similar to that of A. pallidus DSM 3670(T), some physiological properties and the cellular fatty acid profiles differ significantly. A. pallidus strain TD1 can produce extracellular pectate lyase, which has not been reported elsewhere for other bacterial strains in the genus Aeribacillus. A. pallidus strain TD1 may be a good candidate as a pectate lyase producer, which may have useful industrial applications.     

Adsorptive removal of tetracycline from water using Fe(III)-functionalized carbonized humic acid

Humic acid (HA) was carbonized at 300, 400 and 500 °C and then functionalized with 1 wt%–12 wt% Fe(III) respectively [CHA300/400/500-Fe(III)]. Adsorption of such Fe(III)-functionalized carbonized HA as adsorbents to aqueous tetracycline (TC: 25 mg·L⁻¹) was studied. The adsorption equilibrium time for CHA400-Fe(III) to TC was 6 h faster and the adsorption removal efficiency (R_e) was two times higher than that of HA/CHA. The adsorption R_e of CHA400-Fe(III) loaded 10% iron [CHA400-(10%)Fe(III)] to TC could reach 99.8% at 8 h and still kept 80.6% after 8 cycles. The adsorption kinetics were well fitted to the pseudo-second-order equation and the adsorption isotherms could be well delineated via Langmuir equations(R² > 0.99), indicating that the homogeneous chemical adsorption of TC occurred on the adsorbents. The main adsorption mechanisms of TC were complexation Fe(III) and hydrophobic distribution. Electropositive and electronegative repulsion between TC and CHA400-(10%)Fe(III) at lowly pH(2) and highly pH(8–10) respectively, leaded to the relatively low adsorption capacity and more notable influence of ion concentration. When the pH was between 4 and 8, TC mainly existed in neutral molecules (TCH₂), so the influence of ion concentration was not obvious. The dynamic adsorption results showed that the CHA400-(10%)Fe(III) could continuously treat about 2.4 L TC(27 mg·L⁻¹) wastewater with the effluent concentration as low as 0.068 mg·L⁻¹. Our study suggested a broad application prospect of a new, effective, low-cost and environment-friendly adsorbent CHA400-(10%)Fe(III) for treatment of low-concentration TC polluted wastewater.     

N~+注入诱变选育β-葡萄糖苷酶高产菌株及其产酶条件的优化

以筛选得到能够有效利用木糖渣作为碳源生产β-葡萄糖苷酶的菌株为目的,利用N+注入棘孢曲霉L22,筛选得到一株β-葡萄糖苷酶活提高1倍的突变株NIP35。通过单因子实验结合正交实验,对其培养基组成如碳源、氮源、表面活性剂等进行了优化,使其产酶水平最终提高了近2倍。     

33株柯萨奇病毒A组16型分离株的全基因序列分析

目的对2008～2010年北京和青岛地区流行的33株柯萨奇病毒A组16型(Coxsackie virus A16,CA16)分离株的全基因序列进行分析。方法收集2008～2010年北京和青岛地区CA16感染患者咽拭子标本,采用Vero细胞对病毒进行分离,并经噬斑纯化。提取病毒RNA,采用RT-PCR法分段扩增CA16全长基因,经序列测定和拼接后,利用DNAStar和MEGA5.10软件分析全基因序列。结果经病毒分离和噬斑纯化,共获得33株CA16分离株;33个分离株之间的核苷酸序列同源性大于90.9%,与CA16国际标准株G10各区段的核苷酸序列同源性为72.7%～89.0%,氨基酸序列同源性为79.3%～100.0%;与近年中国分离的CA16 SZ/HK08-7株同源性较高,全基因组同源性大于91.5%,各区段核苷酸序列同源性均大于83.7%;在基于VP1序列的种系进化树中,BJWG16、BJWG17、BJWG20等23个分离株属于C1亚型,其余10个分离株属于C3亚型。结论 2008～2010年北京和青岛地区流行的33株CA16分离株均为C基因型。本研究对我国CA16分子流行病学、毒力位点的研究以及疫苗株的选择具有重要意义。     

一株高效絮凝剂菌株的培养条件及应用

筛选到一株高效合成絮凝剂的菌株G-2-3,它能够利用多种碳源和氮源合成絮凝剂,其中以廉价的玉米淀粉和玉米浆培养的絮凝剂的絮凝率达94%以上。在5 L自控发酵罐中,控制pH=5.5～6.0,溶解氧的饱和度(DOT)15%～25%,葡萄糖5.0～7.0 g/L,经25 h发酵培养,该菌的絮凝剂产量达到最高,发酵上清液以3.0 mL.L-1的用量对高岭土悬浮液的絮凝率达98%以上,对煤泥水的絮凝率达90%以上,比阴离子聚丙烯酰胺(APAM)处理煤泥水的最佳絮凝率高出8%以上。菌株G-2-3所产絮凝剂经100℃、30 min保温处理后的絮凝率达80%,在pH=8.5～10.5环境中絮凝率达95%以上,适用于强碱性的生活或工业废水处理。