海洋细菌B-1106生长特性及产胞外多糖研究

对从海泥中筛选到的1株海洋细菌B-1106的生长特性及产胞外多糖进行了初步研究.结果表明,海洋细菌B-1106耐盐度为4 g/dL,培养基初始pH 7.0～8.0,在淡水及海水培养基中产糖量时间均为96 h,产胞外多糖的较佳碳源、氮源分别为蔗糖和硫酸铵,较佳碳氮源质量浓度比为10∶1.     

产抗菌物质海洋细菌B105生长特性及培养条件

对1株产抗菌物质海洋细菌B105的生长特性及培养条件进行了初步研究。结果表明,海洋细菌B105耐盐度3g/100mL~4g/100mL,培养基初始pH值为7.0~8.0,在海水培养基中生长达到高峰时间72h~96h,产抗菌物质较佳时间72h。在最佳条件下,菌株B105产抗菌物质抑菌效果,对金黄色葡萄球菌抑菌圈直径33.6mm,对大肠埃希氏菌抑菌圈直径23.5mm。     

海洋细菌Bn-103产抑菌物质发酵条件及部分理化性质

对从海泥中分离到的一株海洋细菌Bn-103产抑菌物质的培养基、发酵条件及所产抑菌物质的热稳定性、pH值稳定性进行了初步研究。结果表明,海洋细菌Bn-103适宜培养基成分组合为：葡萄糖1 g/dL,蛋白胨0.1～0.3 g/dL,酵母膏0.1 g/dL,海水添加量60%～80%;培养基初始pH 5.0～7.0;接种体积分数2%～4%;发酵时间48～72 h;抑菌物质80℃处理90 min,保留活性80%以上,pH值稳定在pH 3～8之间。     

诗仙太白酒窖泥微生物的分离研究

针对诗仙太白浓香型白酒窖池窖泥中细菌、酵母、霉菌、放线菌、己酸菌及丁酸菌等微生物,选择多种培养基进行分离培养研究。结果表明,牛肉膏蛋白胨培养基+制霉菌素、孟加拉红培养基+氯霉素、孟加拉红培养基+链霉素、高氏Ⅰ号培养基+重铬酸钾+放线菌酮、巴氏培养基、丁酸菌培养基分别对诗仙太白浓香型白酒窖池窖泥中的细菌、酵母、霉菌、放线菌、己酸菌及丁酸菌具有较好的分离效果。     

一株杀线虫活性海洋真菌BH-0531的培养特性及种属鉴定

从渤海湾底水中分离得到的一株具有杀线虫活性海洋真菌BH-0531,考察该菌株的培养特性并进行种属鉴定。结果表明,菌株BH-0531最适海水浓度为20%,最适培养基为20%海水琼脂培养基,最适氮源为硝酸钠,最适pH值为6～7,最适温度为26 ℃。根据菌株BH-0531的形态学观察结果和5.8S rDNA-ITS序列对比发现,菌株BH-0531与Acremonium potronii isolate 35（JX535064.1）高度同源（100%）,被鉴定为波氏枝顶孢霉（A. potronii）的海栖型变种：Acremonium potronii var. marine BH-0531。     

烟草内生细菌分离方法的优化研究

用研磨组织稀释分离法与表面消毒有效性评价相结合的方法确定了适宜烟草组织的表面消毒方法以及内生细菌分离培养基。采用1%次氯酸钠浸泡5分钟,再用75%酒精浸泡2分钟能够100%去除表面附生菌,并且分离得到更多的内生细菌。研究比较了TSA、NA、PDA、LB 四种常用的细菌分离培养基在分离烟草内生细菌中的差异,其中TSA和NA培养基分离得到的内生细菌数量较高,TSA培养基从烟草根、茎、叶中分离出的内生细菌数量分别为5.18 log cfu/g.fw、2.17 log cfu/g.fw、4.69 log cfu/g.fw;NA培养基分别为5.01 log cfu/g.fw、1.81 log cfu/g.fw、4.93 log cfu/g.fw。对分离得到的127株内生细菌进行16S rDNA序列测定表明,TSA和NA培养基分离得到的内生细菌种类最多,其中TSA培养基分别从根、茎、叶中分离到9、7、13种内生细菌;其次是NA培养基,分别从根、茎、叶中分离到8、6、10种内生细菌。结果表明,采用TSA和NA培养基分离烟草内生细菌,可以达到较为理想的分离效果。      

中国舟山海域海水嗜盐假单胞菌多样性分析

目的 研究中国东海舟山海域海水中嗜盐假单胞菌的分布并评价其抗菌活性.方法 采集中国东海舟山海域(东经121°～123°,北纬29°～31°)海水样品14个.分离、纯化、鉴定其中的微生物种类,并评价其抗菌活性.利用PCR技术筛选分离得到的细菌中非核糖体多肽合成酶(NRPS)的分布情况.结果 分离得到的126株细菌中,82...     

窖泥和黄泥微生物分离分析的培养基选择及评价

对黔型浓香型白酒习酒的发酵窖泥及环境土样中微生物区系构成情况进行调查分析,选择多种分别针对细菌、放线菌,酵母菌、丝状真菌等微生物茵群的分离培养基进行了调查探讨.实验结果显示:添加1600 u/mL青霉素钠的培养基可完全抑制原核类微生物菌落的长出.添加0.067%孟加拉红的培养基可抑制部分真菌的扩散生长;选择葡萄糖胰胨琼脂培养基、高氏一号培养基、YEPD培养基或卡尔氏培养基、孟加拉红培养基或淀粉培养基或查氏培养基等,分别用于分离培养细菌、放线茵、酵母菌,丝状真菌等微生物茵群,可获得较好的分离效果和获得更多种群的菌落.在方法学上,采用适合的分离培养基探讨窖泥和黄泥中微生物区系的基本构成是可行的.     

拮抗猕猴桃溃疡病致病菌的海洋细菌的筛选与鉴定

猕猴桃溃疡病是一种严重威胁猕猴桃生产的毁灭性细菌性病害,其致病菌为丁香假单胞菌（Pseudomonas syringae）。本实验旨在利用印度洋海泥中分离出来的115株海洋细菌,从中筛选出对丁香假单胞菌有拮抗作用的海洋细菌。运用滤纸片扩散法对海洋细菌进行初筛,得到33株具有拮抗丁香假单胞菌作用的海洋细菌,利用牛津杯法复筛,筛选出1株海洋细菌NO.357具有最优的抑制效果。对NO.357进行形态学鉴定和生理生化鉴定,通过16S r DNA序列测定和构建系统发育树,鉴定NO.357为低温甲基杆菌（Methylobacterium frigidaeris）。本实验为进一步研究海洋细菌对猕猴桃溃疡病致病菌的拮抗作用以及猕猴桃健康种植奠定基础。     

老白干香型白酒大曲微生物分离培养基的选择

采用多种培养基对衡水老白干酒大曲制曲过程中不同时期的大曲曲坯进行微生物分离。通过对比各种培养基上的微生物种类、菌落数量、形态类别、分离效果等多项指标。结果表明,牛肉膏蛋白胨培养基、MRS培养基、Elliker培养基、马丁氏培养基、麦芽浸出粉培养基分别对老白干香型白酒大曲中的一般性细菌、乳杆菌、乳球菌、霉菌、酵母菌具有较好的分离效果。     

Investigation and culture of microbial contaminants of Caulerpa lentillifera (Sea Grape)

Caulerpa lentillifera is a kind of edible seaweed, known as 'sea grape' or 'green caviar'. It is used in fresh salads. However, it is sensitive to low temperature and osmotic pressure, and is easily spoilt by storage in a refrigerator or washing with tap water. That is the reason why it is difficult to prevent food poisoning, especially due to Vibrio parahaemolyticus. In this study we investigated of marine bacteria and V. parahaemolyticus in C. lentillifera and cultured them in order to develop effective control of bacteria in commercial farms. The sixteen farms in the Okinawa Islands were investigated from August to September in 2006. A total of 176 samples were collected from eleven points during the cultivation processes and from the products. About 10(3) cfu/mL of marine bacteria were detected in the seawater used in the tank culture, but after cultivation of C. lentillifera the number had increased to about 10(6) cfu/mL. The number of marine bacteria in C. lentillifera did not change significantly through the process of planting to the final product (about 10(7) cfu/g). V. parahaemolyticus was detected in seawater from all processes and C. lentillifera was isolated from 56% of seawater, 25% of seed-stocks, and 18.8% of product samples, though but thermostable direct hemolysin gene was not detected from enrichment cultures or isolated V. parahaemolyticus strains. These results indicate that for prevention of food poisoning by V. parahaemolyticus in C. lentillifera, it is important to establish a suitable sterilization procedure for each process.     

一株海洋梅久兰链霉菌的分离鉴定及其抗真菌作用研究

采用梯度稀释分离法从连云港海域海水、海泥、近海土壤、海洋动物以及海洋植物样品中,分离出海洋放线菌22株,采用平板对峙培养法测定不同放线菌菌株的抑菌作用,有9个放线菌菌株有抑菌作用。其中ZW-1菌株的抑制活性最强,该菌株及其发酵液对供试的小麦雪腐镰刀菌(Fusarium nivale)、小麦赤霉病菌(Fusarium graminearum)、斑点落叶病菌(Alternaria alternata)、油菜菌核病菌(Sclerotinia sclerotiorum)、菠菜早疫病菌(Alternaria solani)、玉米圆斑病菌(Helminthosporium carbonum)、西瓜枯萎病菌(Fusarium oxysporum f.sp.niveum)、棉花枯萎病菌(Fusarium oxysporum f.sp.vasinfectum)等8种植物病原真菌都有较强的抑制作用,可导致病原真菌菌丝细胞壁膨大,原生质体收缩,同时可抑制菠菜早疫病菌(A. solani)分生孢子的萌发和芽管的伸长。通过培养特性、细胞形态观察、生理生化实验和16S rDNA序列分析,将海洋放线菌ZW-1菌株鉴定为梅久兰链霉菌(Streptomyces mediolani)。     

Isolation of halotolerant Lactococcus lactis subsp. lactis from intestinal tract of coastal fish

We isolated lactic acid bacteria from the intestinal tract of the pufferfish Takifugu niphobles caught in Shimoda, Shizuoka, Japan by using MRS broth prepared with 50% seawater. Additional screening was carried out using phenotypic tests such as Gram staining, cell morphology, catalase, oxidase and fermentation of glucose. Subsequently 227 isolates screened by the phenotypic tests were subjected to species-specific PCR for Lactococcus lactis, resulting in four positive isolates. The 16S rRNA gene sequences from three isolates were highly similar to that of L. lactis subsp. lactis (DNA database accession number M58837), while that of one isolate was identical to that of Leuconostoc mesenteroides (AB023246). These isolates were characterized by API 50 CH for carbohydrate fermentation and other phenotypic criteria for salt tolerance, and the characteristics were compared with those of L. lactis subsp. lactis from a cheese starter culture. The carbohydrate fermentation profiles of these isolates were characteristic of L. lactis subsp. lactis strains, whereas the tolerance of these isolates to salt was higher than that of L. lactis subsp. lactis from the cheese starter culture: the new L. lactis isolates showed high salt tolerance in MRS-agar plates containing 200% seawater or 6% sodium chloride. This is the first report of the isolation of halotolerant strains of L. lactis subsp. lactis from a marine environment.     

Harvesting energy from the marine sediment--water interface

Pairs of platinum mesh or graphite fiber-based electrodes, one embedded in marine sediment (anode), the other in proximal seawater (cathode), have been used to harvest low-level power from natural, microbe established, voltage gradients at marine sediment-seawater interfaces in laboratory aquaria. The sustained power harvested thus far has been on the order of 0.01 W/m2 of electrode geometric area but is dependent on electrode design, sediment composition, and temperature. It is proposed that the sediment/anode-seawater/cathode configuration constitutes a microbial fuel cell in which power results from the net oxidation of sediment organic matter by dissolved seawater oxygen. Considering typical sediment organic carbon contents, typical fluxes of additional reduced carbon by sedimentation to sea floors < 1,000 m deep, and the proven viability of dissolved seawater oxygen as an oxidant for power generation by seawater batteries, it is calculated that optimized power supplies based on the phenomenon demonstrated here could power oceanographic instruments deployed for routine long-term monitoring operations in the coastal ocean.     

Marine yeasts-a review

Yeasts are ubiquitous in their distribution and populations mainly depend on the type and concentration of organic materials. The distribution of species, as well as their numbers and metabolic characteristics were found to be governed by existing environmental conditions. Marine yeasts were first discovered from the Atlantic Ocean and following this discovery, yeasts were isolated from different sources, viz. seawater, marine deposits, seaweeds, fish, marine mammals and sea birds. Near-shore environments are usually inhabited by tens to thousands of cells per litre of water, whereas low organic surface to deep-sea oceanic regions contain 10 or fewer cells/litre. Aerobic forms are found more in clean waters and fermentative forms in polluted waters. Yeasts are more abundant in silty muds than in sandy sediments. The isolation frequency of yeasts fell as the depth of the sampling site is increased. Major genera isolated in this study were Candida, Cryptococcus, Debaryomyces and Rhodotorula. For biomass estimation ergosterol method was used. Classification and identification of yeasts were performed using different criteria, i.e. morphology, sexual reproduction and physiological/biochemical characteristics. Fatty acid profiling or molecular sequencing of the IGS and ITS regions and 28S gene rDNA ensured accurate identification.     

Temperature effect on nitrogen removal performance and bacterial community in culture of marine anammox bacteria derived from sea-based waste disposal site

Anaerobic ammonium oxidation (anammox) bacteria have been detected in variety of marine environment in recent years, however, there have been only a few studies on their characteristics in the culture. The aim of this study is to reveal the effect of temperature on nitrogen removal ability and bacterial community in a culture of marine anammox bacteria (MAAOB). The MAAOB were cultured from the sediment of a sea-based waste disposal site at the North Port of Osaka Bay in Japan. The maximum nitrogen removal rate (NRR) was observed at 25°C in the MAAOB culture, and it decreased both at below 20°C and over 33°C. The activation energy of the MAAOB culture was calculated to be 54.6 kJ mol(-1) in the 5°C to 30°C range. No significant change in bacterial community according with temperature (5-37°C) was confirmed in the results of polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE). Meanwhile, a number of bacteria related to the oxidation-reduction reaction of sulfur were confirmed and it is speculated that they involved in the activity of MAAOB and nitrogen removal ability in the culture.     

一株拮抗海鱼干优势耐盐真菌芽孢杆菌HY-5筛选及其抗菌成分鉴定

目的:开发新的海鱼干耐高盐优势真菌抑制剂。方法:取用湛江市特呈岛红树林海域的海水、海泥以及红树林的根、茎和叶的样本,利用琼脂扩散法和平板点种法筛选出一株强抗菌活性菌株HY-5,通过传统细胞形态观察并结合生理生化实验及16S rDNA序列进行分析鉴定;利用杯碟法测定上清液对17株霉变海鱼干优势真菌抗菌谱,发酵液酸沉后经LC-MS检测其抗菌成分。结果:HY-5被鉴定为解淀粉芽孢杆菌,其上清液对17株霉变海鱼干优势真菌均有明显抗菌作用;LC-MS检测到HY-5发酵液中含2组抗菌脂肽surfactin(994.6、1008.6、1022.5和1036.6)和iturin(1016.5、1030.5、1044.4和1058.3)组分。结论:海洋源解淀粉芽孢杆菌HY-5的粗提液中含有抗菌脂肽,其对霉变海鱼干优势真菌有较强的拮抗作用。     

Xanthomonas ampelina发酵培养基组成的优化

本文采用正交实验的方法优化了Xanthomonas ampelina TS206发酵培养基的配方,从而达到了提高冰核活性细菌发酵所得的生物量和细菌的冰核活性的目的。实验结果表明较优化的培养基配方为:牛肉膏3.0g/L、蛋白胨5.0g/L、甘油25.0g/L、蔗糖20.0g/L、山梨醇2.0g/L、酵母粉20.0g/L、玉米浆20.0g/L、K2HPO4 1.5g/L、pH=7.0;最终发酵液的生物量达到8.2g/L(干重),冻滴率达到81%。     

Identification of cellulolytic bacteria associated with tunic softness syndrome in the sea squirt, Halocynthia roretzi

The edible ascidian, sea squirt Halocynthia roretzi (Drasche) is marine invertebrate that is a valuable source of foods and bioactive compounds. A severe disease of the sea squirt characterized by degeneration of tunic fibers formed of bundled cellulose microfibrils has occurred. We hypothesized that bacteria lyse the cellulose fibril structure, cellulase activity may be a causative agent of the disease. Among the bacteria isolated from diseased sea squirt, Pseudoalteromonas sp. NO3 had cellulase activity based on a Congo red overlay assay and starch-reducing activity. Sea squirts exhibited 40–100% cumulative mortality after injection with Pseudoalteromonas sp. NO3 using doses of 2×10⁶?2×10⁸ colony forming unit (CFU)/individual. Dead sea squirts possess thinner and ruptured tunics, which were similar to natural outbreaks. These results suggest that Pseudoalteromonas sp. NO3 possessing cellulase activity is one of the causes of tunic softness syndrome in sea squirt.     

植物抽取物对冰核活性细菌表达冰核活性蛋白的影响

植物提取物对于冰核活性细菌表达冰核活性蛋白具有明显的促进作用。通过添加适量的芥菜籽热水抽取物培养冰核活性细菌 (XanthomonasampelinaTS2 0 6) ,细菌的冰核活性比原来提高了 37.5 %,菌体的生物量提高了 36.2 %。芥菜籽抽提物作为一种效应物分子激活启动子 ,在冰核蛋白基因的表达中起到了重要作用 ,从而显著地提高了细菌高水平表达冰核活性蛋白的能力。