破乳菌种TR-1的筛选与破乳性能实验研究

从克拉玛依受石油污染的土壤中筛选出一株原油破乳菌TR-1。介绍了筛选方法。筛选时使用含水原油静置分层产生的油、水相等体积混合制备的W／O乳状液．35℃、50天自发脱水率〈5％；细菌全培养液加量为100mL/L。培养温度35℃，最佳培养pH值7～9．时间5～6天。所得培养液含菌1．1×100个／mL．含干菌体～8．68g／L，35℃、150min脱水率〉90％；2.0g／L干菌体水悬液相同加量时脱水率为80．0％；现用聚醚破乳剂加量100mg／L时脱水率～55％。TR-1菌主要以菌细胞破乳，所产生物表面活性剂也起一定破乳作用。TR-1菌破乳性能稳定，第1、5、25代全培养液的脱水率分别为88．3％、91．7％、80．0％。2．0g／L干菌体水悬液用于克拉玛依采油一厂、二厂含水50．0％、66．7％的稀油破乳（50℃），加量100mL／L时脱水率为66．7％、88．2％．高于现用聚醚破乳剂的脱水率，但对二、三区混合稠油无破乳效果。50℃、150min自发脱水率为16．5％的含水50．0％的稀油，加入5、20、40mg／L聚合物PAM后自发脱水率变为2．0％、4．0％、43．9％，再加入100mL／L干菌体水悬液时脱水率分别为96．5％、80．5％、76．5％．均高于加入100mg／L。化学破乳剂时的相应值。图3表4参6。

人工窖泥的培养操作法

优质的窖泥是生产高质量浓香型曲酒的基本条件之一。培养优质人工窖泥成功的关键主要取决于“种子”是否优良、培养方法是否恰当、配方是否合理3方面。利用对原材料的分析结果来指导窖泥原料的配比,使其各项指标合理;酸度、氨态氮、腐殖质、有效磷等的含量适合,采用适宜的培养温度和密封条件培养并加强管理。(丹妮)

辣椒内生枯草芽孢杆菌(Bacillus subtilis)BS-2和BS-1防治辣椒炭疽病研究

辣椒内生枯草芽孢杆菌(Bacillus subtilis)BS-莉和BS-1,对胶孢炭疽菌(Colletotrichum gloeosporioides)引起的辣椒苗和果炭疽病有良好的防治效果,菌株培养液对苗炭疽病的防效分别为81.5％～93.3％和66.1％～79.2％;对果炭疽病的防效分别为80.0％～100％和60.0％～100％,喷施菌株培养液后间隔24h以上接种病原菌的防病效果比两者同时接种的高。菌株外分泌物对病菌菌丝生长、分生孢子产生和萌发及附着胞形成均有明显的抑制作用。菌株菌体及其胞外分泌物均有防病作用,菌体可能起主导作用。另外,2菌株培养液浸种,对辣椒还有明显的促生效果。BS-2菌株的防病和促生效果均比BS-1高。

浓香型白酒窖池窖泥复壮方案

本方案旨在研究解决现有酒厂窖池窖泥老化问题,通过加入新窖泥测试配比,并植入己酸菌培养液来重新活化窖池窖泥,最终复壮并改善窖池窖泥质量,让窖泥中微生物菌落与繁衍环境达到最佳状态,从而达到提升原酒的风格和品质。本方案通过窖池窖泥复壮后,投粮发酵四轮后的原酒分析数值统计情况看,效果明显,达到预期目的,方案是可行有效的。

一种能同时富集沙门氏菌、金黄色葡萄球菌和单增李斯特菌的培养基

【目的】设计制备一种能够同时富集沙门氏菌、金黄色葡萄球菌及单增李斯特菌的复合增菌肉汤。【方法】挑选合适的添加剂进行单因素实验,确定增菌肉汤的成分及配比,采用平板计数法及三重荧光PCR技术验证肉汤的增菌效果。【结果】结果得到一种能同时富集沙门氏菌、金黄色葡萄球菌及单增李斯特菌的选择性增菌肉汤(SSL),经验证SSL可使得3种目标菌以相对一致的速度进行富集,经过37℃150 r/min振荡培养24 h后,菌体浓度到达107～108CFU/mL,非目标菌生长受到抑制。应用荧光PCR扩增样品,可同时得到3种目标菌的扩增曲线。在710份实际样品检测中,无假阳性及假阴性报告。【结论】研究结果表明,SSL肉汤可用于沙门氏菌、金黄色葡萄球菌及单增李斯特菌的共增菌,可用于多重PCR检测的前增菌。

显微镜下的发现

吮吸手指是幼儿常见的不良习惯,其危害自不必多说。尽管我也想了许多办法,试图让幼儿改掉这一习惯,可收获甚微。后来,我根据幼儿的心理特点,利用显微镜进行观察活动,结果收到了良好的教育效果。 活动前,我从中学实验室借来盛有无菌培养液的玻璃和显微镜,还从医院借来一些齿列畸形和寄生虫病患者的图片。

Classification and Identification of Marine Penicillium Species Based on ITS Sequences of rDNA

[ Objective ] The aim of this study is to identify 6 marine fungi species by analyzing ITS nucleotide sequence, which had been primarily identified as penicillium based on morphological characteristics. [ Method ] The ITS regions of these species were cloned by molecule biology method and phylogenetic analyzed using ClustalX1.83 software. [ Result] The ITS regions of these species were sequenced, and phylogenetic analysis between the yield sequences and the ITS sequences assessed in GenBank showed that the 6 strains all belonged to penicillium. [ Condusion] The present study suggests ITS sequence analysis could not be used as an only proof, but it is a very useful supplementary tool for the classification and identification of marine peniciUium combined with morphological characteristics.

青霉素的功与过

青霉素(Penicillin)是半个世纪来应用于医药方面的一枝独秀,从它之后,临床上又出现数十种抗菌素,至今无论在疗效及抗耐药性上,青霉素可算是抗菌素家族中的侨侨者。目前,临床治疗较普遍使用的为青霉素G(苄青霉素),是一种由青霉菌培养液中提取的天然青霉素。其结晶粉末在室温下保存,效力可保持2～3年。青霉素的抗菌作用强大,低浓度可抑菌。

氨基酸的酶法合成

前言 氨基酸广泛用作食品、医药、饲料、各种工业原料。其制造方法可分为化学合成法,蛋白质水解提取法、发酵法和酶法。现在应用广泛的L-型氨基酸工业上主要已采用微生物的发酵法(谷氨酸、赖氨酸等14种以上)和酶法(赖氨酸、天门冬氨酸、色氨酸、丙氨酸、蛋氨酸等)生产,这比化学合成法优越,因后者制得的是消旋型(DL型)氨基酸,要得到有光学活性的L-型还需拆分。当前酶法生产的氨基酸品种虽比发酵法少,但具有生产工艺简便、

青、链霉素在水产养殖上的应用

青霉素又名盘尼西林,是一种含有氮和硫的有机酸,通常以钠盐或钾盐的形式存在。为易溶于水的白色结晶粉末;链霉素是链丝菌属的链丝菌培养液中提取的一种抗菌素,为易溶于水的白色或淡黄色粉末,有潮解性。两者的作用主要是抑制细菌的生长和繁殖,抗菌作用优于磺胺类药物,有很好的防治鱼病的作用。

Purification and Characterization of a Versatile Peroxidase from Edible Mushroom Pleurotus eryngii

A versatile peroxidase (VP-Peco60-7 ) was generated and purified from the liquid culture of Pleurotus eryngii. The purification procedure included ammonium sulfate precipitation, ion exchange chromatography, and gel chromatography. The molecular weight and isoelectric point (pI) of VP-Peco60-7 were determined to be approxi-mately 40 kDa and 4.1, respectively. By N-terminal sequence determination and peptide mapping analysis, VP-Peco60-7 was found to be similar to the versatile peroxidase isoenzyme VPL1, which was previously isolated from liquid cultures of the same species. However, the molecular weight and pI of VP-Peco60-7 were different from those of versatile peroxidases of liquid cultures, implying that the VP-Peco60-7 in this study is of a novel type. With 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) as a substrate, the maximal enzyme activity was obtained at 50 °C and pH 3.0. The catalysis of ABTS by VP-Peco60-7 was expressed by the Michaelis-Menten equa-tion. At 50 °C and pH 3.0, the maximum velocity (V max ) was 188.68 U·mg-1 and the michaelis constant (K m ) was 203.09 μmol·L-1 .

Production and characterization of exopolysaccharides in mycelial culture of Cordyceps sinensis fungus Cs-HK1 with different carbon sources

The effects of different carbon sources(sugars) on the production and molecular properties of exopolysaccharides(EPS) were evaluated in the mycelial liquid culture of a medicinal fungus Cordyceps sinensis Cs-HK1. Galactose or mannose was used(at 5 g·L^(-1)) as a secondary carbon source with glucose(35 g·L^(-1)) at the mass ratio of 1:7. Mannose was consumed notably since the first day of culture, but galactose was not even after glucose was exhausted.The volumetric yield of EPS in culture was increased slightly with the addition of galactose and decreased with mannose. The monosaccharide composition of EPS was also different, e.g., on day 8, the glucose contents of EPS were 76%with the addition of mannose, 59% with galactose, compared with 62% with glucose only. The molecular weight distribution of EPS was also affected by the secondary carbon source, being generally lower compared with that with glucose only. The results suggested that the addition of galactose improved the total yield of EPS in culture while mannose can improve the yield of glucan constituent of EPS.

Optimization of the Culture Conditions for the Endophytic strain 4-3

Bacillus amyloliquefaciens 4-3 is an excellent plant endophyte that can be used as a good raw material for microecological preparations.For this reason,it is important to optimize the culture conditions of this strain.The number of viable bacteria of strain 4-3 in this study was the evaluation index,and the culture conditions of the liquid fermentation were optimized by single factor experiment.The optimized culture condition was as follows:incubating temperature 32°C,initial pH value 7.2,rotation speed 220 r/min,inoculum concentration 3%and incubating 56 h,under which higher concentrations of Bacillus amyloliquefaciens could be obtained.

Isolation and structural identification of two bioactive phenazines from Streptomyces griseoluteus P510

Phenazine antibiotics phenazine-l-carboxylic acid （PCA） and l-hydroxyphenazine （1-OH-PHZ） were purified from culture broth and mycelia ofStreptomyces griseoluteus P510, Both PCA and 1 -OH-PHZ exhibit strong antifun- gal activity against six plant pathogens, especially Fusarium oxysporium, with minimal inhibition concentrations less than I and 2/ag, ml- 1 for PCA and 1-OH-PHZ, respectively, The presence of PCA and 1 -OH-PHZ indicates that S. griseoluteus PSlO can be used as a potential source of pesticides,

Isolation and Production of Novel β-galactosidase from a Newly Isolated, Moderate Thermophile, Bacillus sp. Strain B1.1

The enzyme β-galactosidase （lactase; EC 3.2.1.23） is a commercially important enzyme due to its various applications in dairy and food industries, which are based on the β-galactosidase-catalysed hydrolysis of lactose into glucose and galactose. The objectives of this work were to identify novel and attractive sources of this industrially relevant enzyme, and to study the effect of selected growth parameters （carbon source, lactose concentration, nitrogen source, peptone concentration, initial pH and temperature） on the formation of β-galactosidase. Based on a screening of isolates from Tha Pai hot spring, Mae Hong Son Province, Thailand, strain BI.1 was selected for further studies. Strain BI.1 is a Gram-positive, rod-shaped, catalase-positive bacterium that forms endospores. Based on the sequence of the 16S rDNA determined, this isolate is most closely related to Anoxybacillus sp. and Bacillus sp., and hence the strain is designated as Bacillus sp. B 1. I.β-Galactosidase was produced by this strain with lactose and peptone as carbon and nitrogen sources, respectively. Optimal enzyme production occurred at an initial culture pH of 8.5 and at 45 ℃. Under these optimum culture conditions, maximal volumetric and specific β-galactosidase activity of 0.478 U mL^-1 and 0.338 U mg^-1 protein, respectively, were obtained after 13 h of cultivation in a medium contain 2.5% lactose, 2.0% peptone, 0.3% K2HPO4, 0.1% KH2PO4 and 0.05% MgSOa·7H2O.

杂乱实验室里诞生的青霉素

有些发明,是因为科学家看到了别人看不到的存在一战中,许多伤员因伤口感染而痛苦死去。参加战地救护的英国医生亚历山大·弗莱明立志找到能杀死病菌的药物。二战中投入使用的抗菌药青霉素挽救了大量伤员的性命,与原子弹和雷达被后人并称二战的三大发明。这种从青霉菌培养液中提制的药物是第一种针对人类传染病的抗生素.以其用途广、安全范围大的优良特性成为医院中必备的普通药品,迄今为止己从传染病手中抢回了数以百万计的生命。

Isolation and Identification of a Di-(2-Ethylhexyl)Phthalate-Degrading Bacterium and Its Role in the Bioremediation of a Contaminated Soil

Di-(2-ethylhexyl) phthalate(DEHP) is a high-molecular-weight phthalate ester(PAE) that has been widely used in the manufacture of polyvinylchloride and contributes to environmental pollution.The objectives of the present study were to isolate a DEHP degrader that can utilize DEHP as a carbon source and to investigate its capacity to biodegrade DEHP in both liquid culture and soil.A bacterial strain WJ4 was isolated from an intensively managed vegetable soil,which was contaminated with PAEs.The strain WJ4 was affiliated to the genus Rhodococcus and was able to remove DEHP from soil effectively.A period of only 7 d was required to degrade about 96.4%of DEHP(200 mg L^(-1)) in the liquid culture,and more than 55%of DEHP(1.0 g kg^(-1)) in the artificially contaminated soil was removed within 21 d.Furthermore,Rhodococcus sp.strain WJ4 had a strong ability to degrade DEHP without additional nutrients in liquid minimal medium culture and DEHP-contaminated soil and to degrade the homologue of DEHP in both liquid culture and soil.Strain WJ4 represents a novel tool for removing PAEs from contaminated soils and it may have great potential for application in the remediation of environmental pollution by PAEs.

Mobilization of Inorganic Phosphorus from Soils by Ectomycorrhizal Fungi

Ectomycorrhizal(EM) fungi could form symbiosis with plant roots and participate in nutrient absorption; however, many EM species commonly found in forest soils, where phosphorus(P) concentration and availability are usually very low, particularly in tropical and subtropical areas, have not yet been investigated for their efficiencies to mobilize soil P. In this study, fungal growth, P absorption,efflux of protons and organic acids, and soil P depletion by four isolates of EM fungi isolated either from acidic or calcareous soils were compared in pure liquid culture using soil as a sole P source. Boletus sp. 7(Bo 7), Lactarius deliciosus 3(Ld 3), and Pisolithus tinctorius 715(Pt 715) from acidic and P-deficient soils of southwestern China showed higher biomass and P concentration and accumulation than Cenococcum geophilum 4(Cg 4) from a calcareous soil of Inner Mongolia, northern China, after 4 weeks of liquid culture. Oxalate, malate, succinate, acetate, and citrate concentrations in the culture solutions varied significantly with fungal species,and oxalate accounted for 51.5%–91.4% of the total organic acids. Organic acids, particularly oxalate, in the culture solutions may lead to the solubilization of iron-bound P(Fe-P), aluminum-bound P(Al-P), and occluded P(O-P) from soil phosphates. Fungal species also varied greatly in proton efflux, which decreased the culture solution pH and may dissolve calcium-bound P(Ca-P) in soil.This could be the reason for the increment of both inorganic P in the culture solutions and Olsen P in the soil when EM fungi were present. Total inorganic P, the sum of Al-P, Fe-P, O-P, and Ca-P, in the culture solutions was positively correlated with the total concentration of organic acids in the culture solutions(r = 0.918*, n = 5), but negatively with both the total inorganic P in soil(r =-0.970**, n = 5) and the culture solution pH(r =-0.830*, n = 5). These suggested variable efficiencies of EM fungal species to mobilize inorganic P fractions from soil, which could make EM trees to utilize inorganic P in the same way like EM fungi and adapt to the soils with various P concentrations and availabilities.

Improving arsenic mobility concentration from As-polluted soils by the functional strains

Arsenic （As） contamination has become the environment issue of global concern. In China, large area of farmland and the site soil were contaminated by As, which means that suitable remedying methods were urgently needed. Phytoremediation, as one of environment-friendly soil remediation techniques developed in recent years, shows a bright future for the remediation of As contaminated soils. However, phytoremediation efficiency needs to be enhanced further because of low concentration of bio- available As in the soils. A triangle flask culture experiment was carried out to study the effects of functional species, isolated from As-polluted soils, that could improve As mobility from the soil. These species included two bacilli, B 1 and B2 （Breviba- cillus） and two fungi, F1 （Trichoderma）, F2 （Fusarium）. They could transform the concentration of As fractionation in the soil sterilized by the method of 6~Co-T ray. Through the experiment, the concentrations of non-specifically-sorbed and specifical- ly-sorbed As fractionation, and pH value of culture solution with inoculated treatment were higher than that with the control. Especially, the concentration of non-specifically-sorbed As fractionation in the treatment-inoculated species was 2 to 6 times higher than that of non-inoculation treatment. Moreover, two bacilli and two fungi could produce IAA, which was conducive to the plant survival when they were jointly used in remedying the As-contaminated soil.