一株海洋细菌HZBN43的鉴定

[目的]鉴定1株分离自黄海海水的细菌菌株HZBN43。[方法]采用16S rRNA技术,对细菌样品株HZBN43进行鉴定,并对其进行系统分析。[结果]通过PCR扩增获得1 521 bp的16S rRNA序列,将其与NCBI已登陆的其他同源序列进行系统分析,确定了此株海洋细菌属于芽孢杆菌属(Bacillus)。虽然与已知种Bacillus selenatarsenatis的相似性为99.79%,但系统分析表明,置信度仅为46,可能受分析序列较短所限。要将其确定到种,尚需要其他研究佐证。     

一株海洋细菌HZBN43的鉴定(英文)

[Objective] The aim of this study is to identify a bacterial strain isolated from ocean water from the Yellow Sea.[Method]Using 16S rRNA technique,a strain from Yellow Sea was preliminarily identified and analyzed.[Result]One 1 521 bp fragment of 16S rRNA was amplified from the strain HZBN43;homology analysis between the yielded sequence and the 16S rRNA sequences accessed in NCBI from other strains showed that HZBN43 belonged to Bacillus,and shared 99.79% homologue with the known species of Bacillus selenatarsenatis.[Conclusion]The sequence of strain HZBN43 was obtained.However,because of the incomplete sequence,the confidence level is just 46,so other corroborations are still required for grouping HZBN43 into an exact species.     

海洋源杀虫细菌100206菌株的发酵条件

通过单因子及正交试验对海洋源杀虫细菌100206的液体发酵条件进行优化筛选。结果显示:适宜的发酵培养基组成为黄豆粉2.00 g、淀粉2.90 g、碳酸钙0.20 g、葡萄糖0.50 g、酵母膏0.25 g、海水75.00 m l、蒸馏水25.00 m l、初始pH值7.50。用菌株100206在28℃、180 r/m in条件下培养72 h得到的发酵原液饲喂棉铃虫初孵幼虫,48 h后棉铃虫死亡率可达66.67%。     

高产纤维素酶的绿色木霉菌种的诱变和筛选(英文)

[目的]诱变和筛选高产纤维素酶的绿色木霉菌种。[方法]利用紫外线对出发菌株进行诱变,经过初筛和发酵检测挑选出高产纤维素酶的菌株。[结果]筛选到高产纤维素酶的绿色木霉K6,酶活是出发菌株的1.39倍。[结论]诱变筛选得到的K6菌株高产纤维素酶,为秸秆纤维素的利用奠定了基础。     

高絮凝活性菌株的筛选及其絮凝特性研究(英文)

[目的]筛选一株高絮凝活性菌株并探究其絮凝特性。[方法]从活性污泥中筛选出一株絮凝剂产生菌,并进行鉴定。对该菌株所产絮凝剂进行提取纯化,并研究其理化性质和絮凝特性。[结果]该菌株被鉴定为沙雷氏菌属(Serratiaplumuthica)。该菌在一定的培养条件下达到最高絮凝活性仅需10h,这有可能大大降低其生产成本。红外分析结果,该菌所产絮凝剂是一种酸性多糖。当微生物絮凝剂用量为0.7mg/L,pH为2-7,温度30-80℃时,均具有很高的絮凝活性。[结论]该菌株所产絮凝剂和其他研究的菌株相比,具有用量少和比较宽泛的pH、温度使用范围的特点。该菌株所产絮凝剂能大大提高活性污泥的沉降能力。     

EalspF1, Essential Enzyme in Isoprenoid Biosynthesis from Eupatorium adenophorum,Reveals a Novel Role in Light Acclimation

Isoprenoids are a functionally and structurally diverse class of natural organic chemicals. The universal precursors of all isoprenoids, isopentenyl diphosphate and dimethylallyl diphosphate are synthesized through the mevalonate and 2C-methyl-D-erythritol 4-phosphate (MEP) pathways, respectively. Many isoprenoids produced through the MEP pathway play an important role in plant acclimation to different light environments. Eupatorium adenophorum, an invasive weed in China, presents a remarkable capacity to acclimate to various light environments, which constitutes its solid foundation of being a successful invasive species. Thus we aimed at gaining a deeper insight into the regulation of MEP pathway in E. adenophorum to further understand the invasive mechanism. 2C-Methyl-D-erythritol 2,4-cyclodiphosphate synthase (IspF or MCS) is an essential enzyme in the MEP pathway. In this paper, a novel IspF gene was cloned and characterized from E. adenophorum. Tissue-specific expression assays revealed a higher expression of EaIspF1 in leaves than in stems and roots. The expression of EaIspF1 was responsive to different light conditions. Some up-regulation of EaIspF1 expression was also found after the treatments with signal compounds and after wounding stress. Interestingly, the over-expression of EaIspF1 in Arabidopsis led to increase carotenoids contents, resulting in an enhanced tolerance to high light. Taken together, these results indicate that the EaIspF1-derived enzyme participates in isoprenoid metabolism and among others, the expression of this gene in E. adenophorum is involved in the regulation of plastidial isoprenoids, which play an important role in acclimation to various light environments.     

EalspF1, Essential Enzyme in Isoprenoid Biosynthesis from Eupatorium adenophorum,Reveals a Novel Role in Light Acclimation

Isoprenoids are a functionally and structurally diverse class of natural organic chemicals. The universal precursors of all isoprenoids, isopentenyl diphosphate and dimethylallyl diphosphate are synthesized through the mevalonate and 2C-methyl- D-erythritol 4-phosphate （MEP） pathways, respectively. Many isoprenoids produced through the MEP pathway play an important role in plant acclimation to different light environments. Eupatorium adenophorum, an invasive weed in China, presents a remarkable capacity to acclimate to various light environments, which constitutes its solid foundation of being a successful invasive species. Thus we aimed at gaining a deeper insight into the regulation of MEP pathway in E. adenophorum to further understand the invasive mechanism. 2C-Methyl-D-erythritol 2,4-cyclodiphosphate synthase （IspF or MCS） is an essential enzyme in the MEP pathway. In this paper, a novel IspF gene was cloned and characterized from E. adenophorum. Tissue-specific expression assays revealed a higher expression of EalspF1 in leaves than in stems and roots. The expression of EalspF1 was responsive to different light conditions. Some up-regulation of EalspF1 expression was also found after the treatments with signal compounds and after wounding stress. Interestingly, the over-expression of EalspF1 in Arabidopsis led to increase carotenoids contents, resulting in an enhanced tolerance to high light. Taken together, these results indicate that the EalspFl-derived enzyme participates in isoprenoid metabolism and among others, the expression of this gene in E. adenophorum is involved in the regulation of plastidial isoprenoids, which play an important role in acclimation to various light environments.     

耐铜菌株TLSB_2-K的鉴定及其铜富集能力测定(英文)

[目的]研究菌株TLSB2-K的铜耐性以及其铜富集能力的特性。[方法]通过形态观察、革兰氏染色和16S r DNA序列比对,对前期分离的菌株TLSB2-K进行了鉴定,并采用振荡培养法,探讨了温度、p H值和渗透压对菌株生长的影响,以及铜胁迫下菌株对铜的耐性及富集能力。[结果]TLSB2-K属于蜡样芽孢杆菌(Bacillus cereus),最适生长条件为:温度为27℃、p H值为7、渗透压为1.1%Na Cl。铜浓度100~500 mg/L范围内,菌体生长良好,铜浓度在100~400 mg/L范围内,菌体铜含量随着铜浓度的升高而增加,当铜浓度400 mg/L胁迫培养30 h,菌体铜含量达到最大值2 250mg/kg;菌株的最高铜耐受浓度为700 mg/L。[结论]菌株TLSB2-K具有较强的铜耐性和较高的铜富集能力,具有重要的理论研究和工程应用价值。     

一株硫化氢脱臭菌的分离、纯化与鉴定

试验将从不同地点采集的三个样品混合后,分离到2株能利用无机硫化物的菌株,优化筛选出菌株N1。通过对菌株N1的形态观察和生理生化试验,将其鉴定为假单胞菌,并确定N1菌株的最适生长温度为30℃、最适pH值为7左右。将H2S气体通入接种了菌株N1的无机硫化物培养基中,H2S明显被去除,并转变为SO42-。     

耐铜菌株TLSB2-K的鉴定及其铜富集能力测定

[目的]研究菌株TLSB2-K的铜耐性以及其铜富集能力的特性.[方法]通过形态观察、革兰氏染色和16S rDNA序列比对,对前期分离的菌株TLSB2-K进行了鉴定,并采用振荡培养法,探讨了温度、pH值和渗透压对菌株生长的影响,以及铜胁迫下菌株对铜的耐性及富集能力.[结果]TLSB2-K属于蜡样芽孢杆菌(Bacillus cereus),最适生长条件为:温度为27℃、pH值为7、渗透压为1.1％ NaC1.铜浓度100～500 mg/L范围内,菌体生长良好,铜浓度在100～400 mg/L范围内,菌体铜含量随着铜浓度的升高而增加,当铜浓度400 mg/L胁迫培养30 h,菌体铜含量达到最大值2 250mg/kg;菌株的最高铜耐受浓度为700 mg/L.[结论]菌株TLSB2-K具有较强的铜耐性和较高的铜富集能力,具有重要的理论研究和工程应用价值.     

施用海洋生物制剂农乐二号对烤烟的影响

研究了海洋生物制剂不同施用方法、施用浓度对烟叶产量和性状的影响.结果表明,农乐二号可提高烟叶产量8.75～15.44 kg/667m2,提高上等烟率3.38%～9.76%,产值增加108.14～177.96元/667m2,且具有显著的抗病抑菌作用,烟叶内在质量和化学成分有所改善,烟叶接近优质烟要求.施用方法以喷施为主,可以灌根,喷施浓度200～300倍液,施用量50～100 L/667m2,灌根用量150 L/667m2.     

一株海水藻类培养液的絮凝活性及机理分析

[目的]研究一株海水藻类培养液的絮凝活性及机理。[方法]由实验室分离保存,一株海水来源的石莼(编号S307)培养液,分析不同因素下该培养液对高岭土悬液的絮凝效果,并探讨絮凝成分及机理。[结果]海藻S307的培养液具有良好的絮凝活性,并且具有较好的热稳定性。在实验室条件下,S307培养液投加量为8%(v/v)时,对高岭土悬液的絮凝活性可达72%;絮凝体系为碱性时,絮凝效果最好;其作用的最佳Ca2+浓度为3.6 mmol/L;结合紫外扫描和絮凝机制的研究结果,初步推测培养液中主要的絮凝物质应该为S307在生长过程中产生的核酸类物质,其中可能含有少量的胞外多糖,主要以离子键结合絮凝高岭土颗粒。[结论]该研究为水处理提供了一种新型絮凝剂。     

海洋真菌MF-08产壳聚糖酶诱导条件及酶学性质分析

通过研究不同摇床转速、不同碳源和碳源浓度、不同诱导碳源对海洋真菌MF-08产壳聚糖酶的影响,提高其产酶活性,并对海洋真菌MF-08产壳聚糖酶进行部分酶学性质研究。结果表明,最佳发酵条件为27℃,150 r/min,1.5%蔗糖,0.01%氨基葡萄糖,海水培养基发酵72 h。该壳聚糖酶的最适作用温度为40℃,最适p H 5.2,酶活在p H 4.0~6.0范围内和0~40℃相对稳定;Cu2+、Fe3+和Hg2+对该酶活具有明显的抑制作用。经过培养条件的优化,该菌的最高产酶活性达到1.769 U/m L,与优化前相比提高了7.56倍。     

山毛豆在岩溶区石漠化治理中的作用

为探讨山毛豆对岩溶区石漠化治理的作用,在广西凌云县典型的石漠化治理示范点阁楼村和加尤镇,在椿树和板栗树林下种植山毛豆和合萌,以坡地种植山毛豆作对照,通过定点监测植被多样性和土壤中养分的变化情况。结果显示,岩溶区种植山毛豆后第1年,植被盖度达到20%~70%,第2年提高到95%~100%,水涵养性提高了3.85%~10.3%,野生物种有害数减少20%~30.7%,土壤有效氮提高6.14%~14.61%,全磷提高23.02%~51.66%,全钾提高38.10%~45.24%,有机质提高6.28%;86.7%的区域土壤有机质属于中等及以上等级,必需微量元素Cu、Mn、Ni、Mo、Sn等有益元素得到提高,有害金属元素中除了Cr外Pb、Ag、As、Hg等均明显减少,其中Hg由原来的三级标准提高到二级标准;阁楼对照区土壤pH值第2年比第1年降低6.47%~10.59%,而山毛豆种植区提高0.40%~6.63%。表明种植山毛豆可以提高石漠化地区植被盖度,提高土壤水涵养性、有效氮和pH值,可以减少野生有害物种的数量和土壤中有害金属元素的含量,具有强大的保持水土和恢复生态环境的作用,可促进石漠化地区土壤和植被正向恢复的演替。     

基于开关电流平衡的含并联输入并联输出结构的三电平DC/DC变换器的调制策略

阐述了三电平DC/DC变换器的发展过程,介绍了其研究焦点的变化:从软开关技术和效率方面转变到性能可靠方面.在此基础上,提出了一种三电平DC/DC变换器(three-level DC/DC converter,TLDC),该变换器由2个四开关半桥三电平(half-bridge three-level,HBTL) DC/DC变换器组成,采用交错和输入-并联-输出-并联(input-parallel output-parallel,IPOP)连接结构,并详细分析了(HBTL) DC/DC变换器的拓扑结构、工作原理、运行特点及工作性能.采用IPOP结构可以有效减小变换器中主要功率元件的电流应力,使得所提出的变换器将更适合于更高功率的应用.更重要的是,通过将所提出的变换器拓扑结构与相应的交换调制(periodically swapping modulation,PSM)策略相结合,不仅2个输入电容器电流得到平衡并大幅降低,而且一次侧的开关管功率也得到了平衡,从而提高了变换器的可靠性.最后,仿真和试验结果验证了该变换器的PSM策略的可行性.