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压力胁迫法从舟山海洋微生物中发现活性化合物的研究

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压力胁迫法从舟山海洋微生物中发现活性化合物的研究

作者： Auckloo Bibi nazia 浙江大学

学位级别：硕士

众所周知,海洋生物圈是一笔巨大的财富,有着来源于海洋植物群和动物群的独特的、有效的生物学活性的天然产物。海洋生物通常在特定的温度、压力、溶解氧和营养可利用性的条件下顽强地生长,因此导致了与陆地生物相比二次代谢产物的生化... 详细信息

众所周知,海洋生物圈是一笔巨大的财富,有着来源于海洋植物群和动物群的独特的、有效的生物学活性的天然产物。海洋生物通常在特定的温度、压力、溶解氧和营养可利用性的条件下顽强地生长,因此导致了与陆地生物相比二次代谢产物的生化差异。同样地,来自Blunt等的报道揭露了从2001年到2015年从海洋生物中总共分离到14637种新型的天然产物。海洋微生物被证明可以产生有着极好活性的化合物,如抗菌、抗肿瘤、抗癌性。更具体地说,在先前的研究中,海洋来源的化合物已经显示出抗菌能力,如在日本,从曲霉菌(***00272)中分离到的Terretonin G。更多有用的资料可以从文献中查到。此外,多样性的生物技术方法的使用显著地促进各种药用目的的化合物的产生。海洋生物技术极大地影响着化学产物、酶和药物,例如从宇螺中分离的齐考诺肽(止痛药)、从海绵中分离到的阿糖胞苷(抗癌)或者从水母(又称为维多利亚多管发光水母)中分离的绿色荧光蛋白。此外,海洋真菌已经被揭露有着极好的抗菌特性,从它们的发现到生产已经深入研究。的确,各种化合物正在处于不同的研究阶段,但是,有效天然产物的工业生产不应该被忽视,当然在工业生产中生物技术方法是优先考虑的。由于缺乏有效的资源,包括基金或人力,方法和技术,在过去的几年里,分离到的有效的抗菌化合物不停地减少。此外,由于进化的观点,病原体具有迅速变异的能力,引起遗传物质的改变,导致耐受性。因此,迫切需要创新方法用来分离和阐明有效抗菌特性的新型候选物。根据Shi等(2015),天然产物的产生可以被通过螯合作用生活在重金属应力环境中的微生物增加。基于以前的研究,“代谢转换”假说可以提出与在应力条件下的耐受菌株产生二次代谢产物有关。同样地,新型有效的代谢物的产生可能受到特定的螯合能力、显著的催化作用和微生物中隐藏的生物合成基因簇的启动的影响。我们的研究引入关于中国舟山海岸的海洋沉积物中分离到的海洋真菌的金属压力胁迫的观点。在这个实验中金属压力的方法指的是在青霉菌(***1122)的培养中使用特定浓度的重金属充当刺激素,极有可能使得隐藏基因簇的开放,因此引起新型二次代谢产物的产生。几种分离得到的新型聚酮化合物的分离和结构阐明被解析,根据抗菌活性筛选出抗葡萄球菌、绿浓杆菌、克雷白氏杆菌的一系列新化合物。在本研究中,钴被选为刺激素来给真菌压力,与正常生长菌株相比较,增强了真菌的抗菌性的表现。为了证明这个假设,对三种病原菌葡萄球菌、绿脓杆菌和克雷白氏杆菌实验,检测钴压力提取物的最小抑菌浓度(MIC)与正常培养的提取物的MIC值相比低很多。此外,基于正常培养组和钴压力培养组的高效液相色谱图的差异,八种代谢物已经成功被分离出来,其中的四种是新型的化合物,四种是已知的化合物。在这篇研究中,我们的重点是关注在半极性的化合物,这些化合物很容易被辨别出来,因为与正常培养组相比新的化合物是新出现的,而且分离度很好。同样地,在高效液相色谱指导的分离中通过应用制备高效液相色谱(C18)对压力代谢物进行分离。钴压力培养被放大并提取分离,应用光谱分析技术,ID、2D核磁共振,高分辨率质谱仪技术,阐明和证实了一种新的黄绿青霉素类似物(1)、一种新的带有一个2,6-二氧杂二环[3,2,1]辛烷环的多烯吡喃酮聚酮化合物(5)、两种新的带有2,5-二氧杂二环[2,2,1]庚烷环的多烯吡喃酮聚酮化合物(7和8)和4种已知的化合物。化合物1是被分离出来是一种微黄色的半固体。通过高分辨率飞行时间质谱仪分析其离子峰在425.1919、403.2102、827.3964 m/z。化合物1的氢谱和碳谱表明了 23个碳原子的相似的化学转换和相同的多样性,这23个碳原子包括一个四氢呋喃环、一个α-吡喃环和一个1,3,5,7-辛四烯,表明化合物1可以推测出有α-吡喃环型的聚酮化合物的基本结构。自然生产的α-吡喃环型的聚酮化合物可以分类为两种主要类型:C24H3407类似物和黄绿青霉素类似物。这两种类型的分子都包含两种确切的结构域:被一条烯烃链连接的α-吡喃环和四氢呋喃环。两种聚酮化合物类似物存在于自然界中,其中C24H3407类似物在大多数结构中被发现了。主要的差异存在于烯烃链,在C24H3407类似物的烯烃链上有3个甲基基团,而在黄绿青霉素类似物的烯烃链上只发现了一个甲基基团。在氢谱中,独特的烯烃质子信号,氢位移5.72(单峰,H-6)、6.37(H-8)、6.35(H-9)、6.59(双峰,J=14.53,11.04Hz,H-10)、6.32(H-11)、7.20(H-12)、6.34(H-13),和甲基质子信号,氢位移在1.94(单峰,H-21),排除了 C24H3407类似物存在的可能性。由于化合物1中缺乏环氧乙烷的亚结构,这个结果被进一步证实。在化合物1的H-H共振中,H8

关键词：海洋微生物活性化合物压力胁迫法抗菌活性

海外并购:政治归属,基于“一带一路”倡议的公平性

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华东师范大学学报（自然科学版） 2020年第S1期 15-23页

作者： FEROZE nazia 程同顺 FAROOQMuhammad Sabil 袁同凯南开大学周恩来政府管理学院政治学系天津300071 南开大学周恩来政府管理学院社会学系天津300071

以"一带一路"倡议为研究视角,选择2009年至2017年中国上市公司的海外并购作为研究样本,探究其权力的性质、政治联系及其对海外并购的影响.研究表明,政治并没有加强企业"一带一路"倡议的并购意愿,但会影响并购交易的规模.国有股的性质对... 详细信息

以"一带一路"倡议为研究视角,选择2009年至2017年中国上市公司的海外并购作为研究样本,探究其权力的性质、政治联系及其对海外并购的影响.研究表明,政治并没有加强企业"一带一路"倡议的并购意愿,但会影响并购交易的规模.国有股的性质对收购意愿和并购规模没有重大影响."一带一路"沿线的海外并购中,政治关联企业的海外并购规模大于非政治关联企业的海外并购规模,政治联系的深度和广度与并购规模呈正相关.中国企业可以通过"一带一路"倡议的实施来促进海外并购,同时注重企业自身的经济利益,实现国家、市场和企业的多赢.

关键词： “一带一路”倡议海外并购政治联系公平性

Metabolic and physiological regulation of Chlorella sp.(Trebouxiophyceae, Chlorophyta) under nitrogen deprivation

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Journal of Oceanology and Limnology 2019年第1期37卷 186-198页

作者： YONG Wai-Kuan LIM Phaik-Eem VELLO Vejeysri SIM Kae-Shin ABDUL MAJID nazia MUSTAFA Emienour Muzalina NIK SULAIMAN Nik Meriam LIEW Kan-Ern CHEN Brenna Jia-Tian PHANG Siew-Moi Institute of Ocean and Earth Sciences University of Malaya Institute of Graduate Studies University of Malaya Institute of Biological Sciences Faculty of Science University of Malaya School of Fisheries and Aquaculture Sciences University of Malaysia Department of Chemical Engineering Faculty of Engineering University of Malaya Airbus Group Malaysia Menara HLA Aerospace Malaysia Innovation Centre

A freshwater green microalgae Chlorella sp., UMACC344 was shown to produce high lipid content and has the potential to be used as feedstock for biofuel production. In this study, photosynthetic effciency, biochemical pro?les and non-targeted metabolic pro?ling were studied to compare between the nitrogen-replete and deplete conditions. Slowed growth, change in photosynthetic pigments and lowered photosynthetic effciency were observed in response to nitrogen deprivation. Biochemical pro?les of the cultures showed an increased level of carbohydrate, lipids and total fatty acids, while the total soluble protein content was lowered. A trend of fatty acid saturation was observed in the nitrogen-deplete culture with an increase in the level of saturated fatty acids especially C16:0 and C18:0, accompanied by a decrease in proportions of monounsaturated and polyunsaturated fatty acids. Fifty-nine metabolites, including amino acids, lipids, phytochemical compounds, vitamins and cofactors were signi?cantly dysregulated and annotated in this study. Pathway mapping analysis revealed a rewiring of metabolic pathways in the cells, particularly purine, carotenoid, nicotinate and nicotinamide, and amino acid metabolisms. Within the treatment period of nitrogen deprivation, the key processes involved were reshu ? ing of nitrogen from proteins and photosynthetic machinery, together with carbon repartitioning in carbohydrates and lipids.

关键词： metabolic profiling Chlorella sp. nitrogen stress lipid fatty acid

Impact of Different Parameters on Life Cycle Analysis, Embodied Energy and Environmental Emissions for Wind Turbine System

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Journal of Environmental Protection 2016年第7期7卷 1005-1015页

作者： nazia Binte Munir Ziaul Huque Raghava R. Kommalapati Center for Energy & Environmental Sustainability Prairie View A&M University Prairie View TX USA Department of Mechanical Engineering Prairie View A&M University Prairie View TX USA Department of Civil and Environmental Engineering Prairie View A&M University Prairie View TX USA

Due to the rapid depletion of fossil fuel reserves and increasing concern for climate change as a result of greenhouse gas effect, every country is looking for ways to develop eco-friendly renewable energy sources. Wind energy has become a good option due to its comparative economic advantages and environment friendly aspects. But there is always an ongoing debate if wind energy is as green as it seems to appear. Wind turbines once installed do not produce any greenhouse gases during operation, but it can and may produce significant emissions during manufacture, transport, installation and disposal stages. To determine the exact amount of emissions, it is necessary to consider all the stages for a wind turbine from manufacture to disposal. Life Cycle Analysis (LCA) is a technique that determines the energy consumption, emission of greenhouse gases and other environmental impacts of a product or system throughout the life cycle stages. The various approaches that have been used in the literature for the LCA of wind turbines have many discrepancies among the results, the main reason(s) being different investigators used different parameters and boundary conditions, and thus comparisons are difficult. In this paper, the influence of different parameters such as turbine size, technology (geared or gearbox less), recycling, medium of transport, different locations, orientation of the blade (horizontal or vertical), blade material, positioning of wind turbine (land, coastal or offshore), etc. on greenhouse gas emissions and embodied energy is studied using the available data from exhaustive search of literature. This provides tools to find better solutions for power production in an environmental friendly manner by selecting a proper blade orientation technique, with suitable blade material, technology, recycling techniques and suitable location.

关键词： Embodied Energy Energy Payback Time Emissions Life Cycle Analysis Wind Energy

Can outer-to-outer diameter be used alone in diagnosing appendicitis on 128-slice MDCT?

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World Journal of Radiology 2014年第12期6卷 913-918页

作者： Jamal Yaqoob Muhammad Idris Muhammad Shahbaz Alam nazia Kashif Department of Radiology Dallah Hospital Resident Radiology Department Peoples Medical College

AIM: To assess the frequency of visualization, position and diameter of normal appendix on 128-slice multidetector computed tomography(MDCT) in adult ***: Retrospective cross sectional study conducted at Radiology Department, Dallah Hospital, Riyadh, Saudi Arabia from March 2013 to October 2013. Non-enhanced computed tomography scans of abdomen and pelvis of 98 patients presenting with hematuria(not associated with abdominal pain, fever or colonic disease) were reviewed by two radiologists, blinded to patient history. The study group included 55 females and 43 males with overall mean age of 54.7 years(range 21 to 94 years). The coronal reformatted images were reviewed in addition to the axial images. The frequency of visualization of appendix was recorded with assessment of position, diameter and luminal ***: The appendix was recorded as definitely visualized in 99% of patients and mean outer-to-outer diameter of the appendix was 5.6 ± 1.3 mm(range 3.0-11.0 mm).CONCLUSION: MDCT with its multiplanar reformation display is extremely useful for visualization of normal appendix. The normal appendix is very variable in its position and diameter. In the absence of other signs, the diagnosis of acute appendix should not be made solely on outer-to-outer appendiceal diameter.

关键词： Normal appendix Multidetector computed tomography Appendiceal enlargement Computed tomography

Divergent trajectories of lean vs obese non-alcoholic steatohepatitis patients from listing to post-transplant:A retrospective cohort study

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World Journal of Gastroenterology 2022年第26期28卷 3218-3231页

作者： Fakhar Ali Qazi-Arisar Raj Uchila Catherine Chen Cathy Yang Shi-Yi Chen Ravikiran Sindhuvalada Karnam Amirhossein Azhie Wei Xu Zita Galvin nazia Selzner Leslie Lilly Mamatha Bhat Ajmera Transplant Program Toronto General HospitalUniversity Health NetworkToronto M5G 2N2OntarioCanada Division of Gastroenterology and Hepatology Department of MedicineUniversity of TorontoToronto M5G 2N2OntarioCanada National Institute of Liver and GI Diseases Dow University of Health SciencesKarachi 75330Pakistan Department of Biostatistics Princess Margaret Cancer CenterUniversity Health NetworkToronto M5G 2C1OntarioCanada Division of Biostatistics Dalla Lana School of Public HealthUniversity of TorontoToronto M5G 2C1OntarioCanada

BACKGROUND Non-alcoholic steatohepatitis(NASH)cirrhosis is the second most common indication for liver transplantation(LT).The role of body mass index(BMI)on outcomes of NASH cirrhosis has been *** To compare the longitudinal trajectories of patients with lean vs obese NASH cirrhosis,from listing up to post-transplant,having adjusted their BMI for *** We retrospectively reviewed all adult NASH patients listed for LT in our program from 2012 to ***-Gray Competing Risk analyses and Cox Proportional-Hazard Models were performed to examine the cumulative incidence of transplant and survival outcomes *** Out of 265 NASH cirrhosis listed patients,176 were *** age was 61.0 years;46%were females.111 patients underwent *** robust patients had better waitlist survival[hazard ratio(HR):0.12;95%CI:0.05–0.29,P<0.0001]with higher instantaneous rate of transplant(HR:5.71;95%CI:1.26–25.9,P=0.02).Lean NASH patients had a substantially higher risk of graft loss within 90 d post-LT(1.2%vs 13.8%,P=0.032)and death post-LT(2.4%vs 17.2%,P=0.029).1-3-and 5-year graft survival was poor for lean NASH(78.6%,77.3%and 41.7%vs 98.6%,96%and 85%respectively).Overall patient survival post-LT was significantly worse in lean NASH(HR:0.17;95%CI:0.03–0.86,P=0.0142)with 83%lower instantaneous rate of death in obese *** Although lean NASH is considered to be more benign than obese NASH,our study suggests a paradoxical correlation of lean NASH with waitlist outcomes,and graft and patient survival post-LT.

关键词： Outcomes Frailty Waitlist Liver transplant Survival

Influence of Ni substitution on structural,morphological,dielectric,magnetic and optical properties of Cu-Zn ferrite by double sintering sol–gel technique

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Journal of Advanced Dielectrics 2019年第2期9卷 63-71页

作者： Mohammad Sajjad Hossain Yeasmin Akter Mohammad Shahjahan Muhammad Shahriar Bashar MostHosney Ara Begum MdMoazzem Hossain Suravi Islam nazia Khatun MdAl-Mamun Industrial Physics Division BCSIR Laboratories Dhaka BCSIRDhaka-1205Bangladesh Department of Physics University of Chittagong Chottogram-4331Bangladesh Institute of Fuel Research and Development BCSIR Dhaka-1205Bangladesh Bangladesh Atomic Energy Centre BAEC Dhaka-1000Bangladesh

Polycrystalline NiCuZn ferrite(Ni_(x)Cu_(0.3)Zn(0.7-x)Fe_(2)O_(4);x=0.2,0.3,0.4 and 0.5)were prepared through solgel auto combustion method applying double sintering ***,morphological,elemental analyses(EDS),Fourier-transform infrared spectroscopy(FTIR),Direct Current(DC)electrical resistivity,dielectric,magnetic and optical properties of prepared samples were *** profiles reveal the formation of simple cubic spinel structure without any traceable *** average crystallite size lies within the range of 22–29 *** parameter decreases with increasing Ni *** temperature DC resistivity was recorded from 6:39×10^(5)to 3:79×10^(5)Ω*** dielectric constant(ε)and loss factor(tanδ)were decreased with increase of frequency while AC conductivity *** absorption peak occurred at three different frequency ranges at 570-577 cm^(-1),1635-1662 cm^(-1)and 3439–3448 cm^(-1).Magnetic properties were investigated by using vibrating sample magnetometer(VSM).Decreasing trends were observed for saturation magnetization(Ms),magnetic coercivity(Hc)and remanant magnetization(Mr)with the increase of Ni *** band gap(-2.70-2.79 eV)were calculated from diffuse reflectance data by using Kubelka–Munk function.

关键词： Sol-gel NiCuZn ferrite FTIR DC resistivity dielectric optical properties

An Efficient Procedure for DNA Isolation and Profiling of the Hyper Variable MtDNA Sequences

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Journal of Life Sciences 2015年第11期9卷 530-534页

作者： nazia Akbar Habib Ahmad Muhammad Shahid Nadeen Nasir Ali Muhammad Saadiq Department of Genetics Hazara University Garden Campus Mansehra 21300 Pakistan Department of Chemistry Bacha Khan University Charsadda Khyber Pakhtunkhwa Pakistan

Present study describes the results of an efficient protocol for the isolation of good quality DNA from human saliva. The protocol includes collection of saliva in sterile specimen tubes, followed by the cell lysis. After formation of cell lysate, proteins wereextracted by phenol chloroform treatment for purification of DNA. The purified DNA was precipitated by adding equal volume of isopropanol to the treated supernatant. After isolation DNA pellet was washed with 70% ethanol, air-dried and was suspended in 30 pL of double distilled water. Best quality of DNA was extracted from the saliva samples and the PCR product was amplified for hyper-variable regions （HVI＆ HV2） of the mitochondrial DNA. The genes were cleaned with GeneAll gel elution kit （Gel SV）（Cat. No. 102-10） and sequenced accordingly. The DNA isolation protocol presented here is recommended for the isolation, best quality and yield of DNA from the human saliva.

关键词： Human saliva DNA isolation mtDNA sequences forensic study.

Implications of Different DEMs on Watershed Runoffs Estimations

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Journal of Water Resource and Protection 2019年第4期11卷 448-467页

作者： nazia N. Arbab Jean Marie Hartman Johnny Quispe Jason Grabosky Department of Ecology Evolution and Natural Resources Rutgers University New Brunswick NJ USA Department of Landscape Architecture Rutgers University New Brunswick NJ USA

Watershed modelling tools like ArcSWAT, an ArcGIS extension of Soil and Water Assessment tool (SWAT), are useful to watershed managers in many ways. One particular use is analyzing model outputs for decision making related to waterway restoration and mitigation, which is often undertaken to improve water quality in streams. The present study evaluates the use of digital elevation model (DEM) at 10 meter, 30 meter, and 100 meter pixel size on non-point runoff predictions for three sub-watersheds in Raritan River Basin in New Jersey. These three watersheds include: Bound Brook, Lamington River, and Lawrence Brook watersheds. ArcSWAT is utilized to investigate the difference due to DEM variation in predicting monthly estimates of pollutant loads including ammonium (NH4), nitrite (NO2) and sediment transported with water out of a watershed. Using land use/cover, slope and soil data for 2012, monthly pollutant loads are calculated for each sub-basin in the watershed over a 10-year simulation period (2012-2022) in ArcSWAT. Overall statistical and spatial results show that ArcSWAT results are sensitive to changes in DEM pixel size for watershed modeling. The results show that total sum of monthly runoffs including NH4, NO2 and sediment differ among the three different DEMs. Moreover, the spatial pattern of input (in sub-catchments) also changes among the three DEMs for most watersheds. This indicates that watershed managers need to supplement model predictions with field measurements before making substantial investments in stream restoration programs.

关键词： Runoffs DEM SWAT Stream Restoration Watershed Characteristics Watershed Modeling