除油生物表面活性剂产生菌的分离及其特性

为了对石油污染的土壤进行生物修复,从大庆油田油泥和油田污水中富集培养、分离得到52株菌,通过对各菌株的排油活性及表面张力实验,优选出菌株B381、B101、B64和C43,它们产生的表面活性剂的表面张力较低,并且表面活性稳定.对纯化的表面活性剂分析表明,表面活性剂的主要成分为脂肽类(Lipopeptide)、鼠李糖脂(Rham nolipid)、槐糖脂(Sophrolipids)及甘油酯类(G lyceride)化合物.用这4株菌的发酵液进行了油泥处理实验,72 h后石油去除率平均达70%以上.与对照样品相比,石油去除率提高到大约7~9倍.     

产纳豆激酶的枯草芽孢杆菌基因工程菌发酵条件的响应面优化

采用实验室前期构建的能够高产纳豆激酶的枯草芽孢杆菌基因工程菌株,对其液体发酵条件进行优化。通过单因素实验和响应面Box-Behnken模型优化液体发酵培养参数,五因素三水平的响应面分析表明最佳发酵培养条件为:蛋白胨26.05 g/L,葡萄糖29.29 g/L,MgSO4 1.5 g/L,CaCl2 0.74 g/L,NaCl 10 g/L,pH 9.0,接种量3 %。在最优发酵培养条件下,纳豆激酶最高酶活达到2 186.17 IU/mL,比优化前提高了269 % ,这表明响应面法优化枯草芽孢杆菌工程菌能够明显的提高纳豆激酶活性,为该菌株规模化生产纳豆激酶提供了基础应用参考。     

高产蛋白酶活性的枯草芽孢杆菌筛选及鉴定

通过透明圈法从土壤中筛选出20株能分泌胞外蛋白酶的芽孢杆茵,并使用福林-酚试剂法测定了其中透明圈（H／C）值较大的6株和三种市购枯草芽孢杆茵发酵茵液的中性蛋白酶活性。选择中性蛋白酶活性最强的CDY-5菌株（23．44U／mL）及透明圈（H／C）值最大的CDY-1茵株（3．75）,进行16SrRNA基因测序后,通过MEGA软件构建系统发育树得出菌株CDY-1为巨大芽孢杆茵,CDY-5为枯草芽孢杆茵。     

聚合物/表面活性剂二元体系油水乳化过程动态表征方法研究

提出了一种新的通过测量油滴粒径变化来表征油水乳状液动态特性的方法,采用粒度分析仪测量了不同体系模拟油水乳状液油滴粒径的变化。比较了十二烷基苯磺酸钠(SDBS)、壬基酚聚氧乙烯醚(NP-10)和乙氧基化烷基硫酸钠(AES)所形成模拟乳状液的动态特性,测定了聚合物和乙醇在复合体系中对乳化过程的影响,并初步探讨了作用机理。结果表明:该方法不仅可以反映出不同体系的油水乳化速度,而且可以比较乳状液中油滴的粒径大小及其随时间变化的规律,这对于研究实际驱油过程中乳状液的形成和稳定具有重要的意义。     

桂林猫儿山地区Bt菌株的筛选及其抑菌成分的热稳定性

通过对桂林猫儿山原生态地区采集的166份土样样品进行筛选,分离到含有新的杀虫晶体蛋白基因、所产抑菌物质热稳定性好的苏云金芽胞杆菌菌株。采用温度筛选法对土样进行初筛和复筛,结合SDS-PAGE分析和牛津杯法抑菌试验来挑选目的菌株。从采集的166份天然土壤样品中分离出49株苏云金芽胞杆菌,出菌率29.5%。光学显微镜观察发现有大菱形、小菱形和不规则晶体类型。用SDS-PAGE分析了其中14株野生菌株的杀虫晶体蛋白表达谱,发现14株均表达了130和65 k D的蛋白,其中有7株表达约90 k D蛋白、2株表达35 k D和6株表达30 k D的蛋白。对其中8株表达不同分子量蛋白的菌株发酵44h,取其发酵液的上清液进行抑菌活性成分热稳定性检测,发现其热稳定性相差较大,95℃水浴加热2 h处理后,除247-1外,其他几株产生的抑菌物质全部失活。菌株247-1不仅产生耐热的Zwittermicin A,可能还产生其他热敏感性的抑菌成分。     

一种天然维生素E微囊的制备及其性能表征

使用几种不同的壁材及乳化剂对天然维生素E进行微胶囊化,通过对比微囊化效果确定最佳选材及条件,并对最终产品各项性能指标进行测定.结果表明,最佳壁材为纯胶(GUM 2000)与蔗糖,最佳乳化剂为蔗糖酯S1570(HLB 15),壁材比例m(纯胶)∶ m(蔗糖)为2∶1,乳化剂加入量为0.5％,喷雾干燥进风口温度180～19...     

聚合物/表面活性剂驱模拟采出水的乳化稳定性

以成分相对简单的轻质油(V(石油醚):V(苯)=9:1)作为模拟油取代成分复杂的原油配制模拟采出水,详细探究了驱油剂影响聚合物/表面活性剂二元复合驱采出水乳化稳定性的机理。采用超低界面张力仪、Zeta电位分析仪和界面流变仪对油水界面张力、油滴表面Zeta电位和油水界面流变进行测定,研究了部分水解聚丙烯酰胺(HPAM,聚合物)、石油磺酸盐(WPS,表面活性剂)和矿化度对模拟采出水油水分离性能的影响。研究结果表明:WPS能够降低油水界面张力,使模拟采出水更加稳定。HPAM能够增加模拟采出水体相黏度,但对其最终乳化稳定性影响较小。矿化度增加显著增强了模拟采出水乳化稳定性,从而为进一步加深对采出水乳化稳定性的研究提供借鉴。     

Production and characterization of alkaline extracellular lipase from newly isolated strain Aspergillus awamori HB-03

A strain HB-03 to produce alkaline extracellular lipase was isolated from oil-rich soil samples and identified as Aspergillus awamori.The growth conditions and nutritional factors for lipase production by strain HB-03 were optimized,and the maximum lipase production of (45.9±2.3) U/mL was obtained at 30 °C and pH 7.0 after 36 h using olive oil (1%) and sucrose (0.5%) as carbon sources and combination of peptone (2%),yeast extract (0.5%) and ammonium sulfate (0.1%) as nitrogen sources.The lipase was purified...     

表面活性剂T154和Span80对W/O型单重乳状液膜稳定性的影响

采用单因素实验法分别进行了表面活性剂T154和Span80制备W/O单重乳状液膜的研究。重点考察了表面活性剂体积分数、制乳搅拌速度、油内比、内相NaOH浓度和乳液静置时间对两种表面活性剂制备的乳状液膜破损率的影响并进行了比较。结果表明,T154和Span80制备的乳状液膜的破损率均随各考察因素的增大而降低或升高（除制乳搅拌速度外）,但前者降低或升高的幅度显著低于后者。实验确定了T154制备乳状液膜的最适宜条件,在此条件下,当乳状液膜静置时间为1、4、8 h时,其破损率分别为2.3%、4.7%和7.8%,显著低于Span80制备的乳状液膜的破损率9.2%、21.9%和48.4%。     

聚丙烯酸酯/聚硅氧烷共聚乳液的合成与表征

为了提高聚丙烯酸酯的耐寒热性能,制备了新型聚丙烯酸酯/聚硅氧烷共聚物.采用聚硅氧烷乳液为种子乳液,将丙烯酸酯和聚硅氧烷进行乳液共聚,合成了该共聚物乳液.探索了D4和VD4物质的量之比对聚合稳定性的影响.利用红外（IR）光谱表征了共聚物结构,利用差示扫描量热法（DSC）和热重分析（TGA）测试了共聚物的玻璃化转变温度和最大热分解温度.研究结果表明,聚硅氧烷被有效地共聚到丙烯酸酯单体中.当硅氧烷单体中D4和VD4物质的量之比大于10∶1时,该共聚物乳液聚合稳定性好.随着硅氧烷质量分数的增加,该共聚物的耐热性、耐寒性和耐水性均得到提高.     

TiO_2/PBA/PMMA核壳粒子的制备与表征

纳米粒子是热力学不稳定体系,容易发生颗粒团聚。为了更好地改善纳米粒子的分散性,本文报道利用乳液聚合的方法制备以表面处理过的纳米二氧化钛为核丙烯酸丁酯和甲基丙烯酸甲酯为壳的TiO2/PBA/PMMA复合粒子。分析二氧化钛、乳化剂、引发剂、反应温度和超声震荡时间等因素对聚合反应单体转化率的影响,并表征核壳复合粒子。结果表明,利用乳液聚合方法制备的二氧化钛粒子为核壳结构,平均粒径为251 nm,其粒径分布较未改性纳米TiO2明显变窄,改善了纳米粒子的分散性。     

TiO2／PBA／PMMA核壳粒子的制备与表征

纳米粒子是热力学不稳定体系，容易发生颗粒团聚。为了更好地改善纳米粒子的分散性,本文报道利用乳液聚合的方法制备以表面处理过的纳米二氧化钛为核丙烯酸丁酯和甲基丙烯酸甲酯为壳的TiO2／PBA／PMMA复合粒子。分析二氧化钛、乳化剂、引发剂、反应温度和超声震荡时间等因素对聚合反应单体转化率的影响，并表征核壳复合粒子。结果表明，利用乳液聚合方法制备的二氧化钛粒子为核壳结构。平均粒径为251nm。其粒径分布较未改性纳米TiO2明显变窄,改善了纳米粒子的分散性。     

鲍鱼腹足胶原蛋白的提取及性质研究

测定了鲍鱼腹足的基本组成成分,对皱纹盘鲍酶促溶性胶原蛋白(PSC)的提取及相关性质进行了研究。结果表明,用酶法提取的鲍鱼腹足PSC得率为8.72%(以干基计)。圆二色谱分析表明,鲍鱼腹足PSC溶液在221和199nm分别有一正、负峰,是具有典型三螺旋结构的胶原蛋白特征圆二色谱峰型。鲍鱼腹足PSC等电点为pH 5.17;质量浓度0.3 mg/mL、pH 3.0～3.5的PSC溶液起泡性达110%,泡沫稳定性较差,乳化性好,为100%;但乳化稳定性一般,放置5h后,仅保持在50%左右。鲍鱼腹足PSC具有较高的Fe2+螯合活性,其IC50值为0.348mg/mL,当质量浓度为1.2mg/mL时Fe2+螯合能力可达91.62%。     

Isolation and characterization of Acidithiobacillus caldus from several typical environments in China

Six strains of moderately thermophilic sulfur-oxidizing bacteria were isolated from several different typical environments in China. The identities of the isolates were confirmed by analyses of their 16S rRNA genes, and some key physiological traits. The isolates are Gram negative, rod-shaped bacteria, their optimal temperature and pH value for growth are 45-50 ℃ and 2.5-3.5 respectively. They are autotrophic and used＇elemental sulfur, sodium thiosulfate and potassium tetrathionate as electron donor, while a little glucose stimulated their growth. 16S rDNA sequences analysis reveals that the strains are phylogenetically clustered to Acidithiobacillus caldus.     

植物油脂肪酸烷醇酰胺的合成与性能表征(Ⅰ)──植物油脂肪酸甲酯的合成与工艺优化

以植物油和甲醇为原料合成了植物油脂肪酸甲酯，通过正交实验方法优化了合成工艺条件，产品 收率达８５％以上．     

Purification and characterization of extracellular chitinase from a novel strain Aspergillus fumigatus CS-01

Twelve samples derived from different locations in south central area of China are treated by enrichment and spread-plate technique for initial screening. Seven chitinase-producing strains are isolated. The chitinase present in the culture supernatant of strain CS-01 possesses the maximum activity of 0.118 U/mL. Analysis of the morphological feature and the ITS rDNA sequence reveals that strain CS-01 belongs to Aspergillus fumigatus. Production of the chitinase is regulated by a inducible way and the maximum activity appears at 36 h in colloidal chitin culture. Purification of the chitinase is carried out by salting out, gel filtrate chromatography and anion exchange chromatography sequentially. Native-PAGE and SDS-PAGE indicate that the chitinase from A. fumigatus CS-01 is a monomer with the relative molecular mass estimated to be 4.50×10⁴. Its maximum activity appears at pH 5 and 55 °C. The chitinase is stable at pH 4.0–7.5 and below 45 °C. Foundation item: Projects(50621063, 50674101) supported by the National Natural Science Foundation of China     

双酚A型苯并噁嗪树脂/蒙脱土纳米复合材料的制备与表征

为解决苯并噁嗪树脂(BZ)固化温度高和固化后韧性差的问题,首先制备了苯并噁嗪叔铵盐(Bz盐),并通过阳离子交换反应对蒙脱土(Na-MMT)进行改性,得到Bz盐改性蒙脱土(Bz-MMT);其次,将Bz-MMT与BZ共混,通过除泡和加热固化,制备了苯并噁嗪树脂/蒙脱土纳米复合材料(PBZ/Bz-MMT);最后,采用X射线衍射(XRD)、差示扫描量热法(DSC)和热重分析(TGA)等对Bz-MMT、BZ和MMT的混合物以及固化后的PBZ/Bz-MMT纳米复合材料进行分析,分别考察了Bz盐的用量对Bz-MMT层间距和热稳定性的影响、Bz-MMT对BZ的固化温度以及对PBZ/Bz-MMT热稳定性和力学性能的影响.结果表明:随着Bz盐用量的增加,Bz-MMT的层间距基本不变、有机含量提高、起始热分解温度降低;采用Bz-MMT改性BZ,不仅可以降低BZ的起始固化温度,而且能有效地提高PBZ/Bz-MMT的"残炭率"、拉伸强度和冲击强度.     

Fractionation and characterization of polysaccharides from cyanobacterium Spirulina （Arthrospira） maxima in nitrogen-limited batch culture

By a sequentially selective extraction procedure, polysaccharides (PS) from cyanobacterium Spirulina (Arthrospira) maxima that can be bio-functionally healthy components were fractionated in four parts including the culture medium (PSCM), the external layers of the cell (PSEL), the cell wall (PSCW) and storage granules (PSSG). The four fractionated parts of polysaccharides were characterized by gas-liquid chromatography (GLC) equipped with FID and fused-silica capillary column (15 m×0.53 mm i. d.). The contents of PSCM, PSEL, PSCW and PSSG were about 2.0%, 2.6%, 10.0% and 52.0% to cell dry matter, respectively. Glucose was almost the only monosaccharide in PSSG and PSCW and most predominant in PSEL, while in PSCM, xylose, rhamnose and glucose were the main ones. Two uronic acids represented by glucuronic acid and galacturoic acid, six neutral monosaccharides including fucose, rhamnose, xylose, mannose, galactose and glucose, and two possible unidentified sugars were found in PSEL and PSCM. These data are valuable for the selective productions of high-added value sugars from Spirulina. Foundation item: Scholarship for Ph. D at FPMs, Belgium Biography of the first author: NIE Zhen-yuan, Engineer in biomedicine, born in 1963, majoring in biotechnology and bioengineering.     

Thermal stability and long-acting antibacterial activity of phosphonium montmorillonites

Na-montruorillonite (Na-MMT) was exchanged with three quaternary alkylphosphonium salts:decyl tributylphosphonium bromide (DTBPBr), dodecyl tributylphosphonium bromide (DDTBPBr) and hexadecyl tributylphosphonium bromide (HDTBPBr), to investigate the effects of phosphonium salts species and relative molecular mass on the characteristics, morphology, thermal stability and long-acting antibacterial property of phosphonium montmorillonites. The resulting modified montmorillonites were characterized by the FTIR, XRD, TEM, and TG/DTG techniques. And minimum inhibitory concentration (MIC) was used to investigate antibacterial activity. The results show that the phosphonium salts are intercalated into Na-MMT, and the basal spacing of P-MMTs is enlarged with the increase of phosphonium salt content or the growth of alkyl chain length. DDTBP-MMT-3 with 19.83% (mass fraction) of dodecyl tributylphosphonium salts, displays excellent thermal stability and long-acting antibacterial activity.     

Chemical component and antimicrobial activity of volatile oil of Calycopteris floribunda

The volatile oil of leaves and barks of Calycopteris floribunda was examined by gas chromatography-mass spectrometry (GC-MS). 52 volatile chemical components in leaves were identified. The antimicrobial assay of oils in the leaves and barks was carried out by disk diffusion method in vitro. The major components (mass fraction) in leaves are caryophyllene oxide (13.79%), n-hexadecanoic acid (11.91%) and β-caryophyllene (10.45%). Ten constituents are identified accounting for about 99.98% of the total volatile oil in the bark. Among these components, n-hexadecanoic acid (59.18%), linolic acid (12.70%) and butyl octyl phthalate (8.21%) are the major constituents. The oils exhibit strong antimicrobial activity and display more potent against bacteria than fungi.