细菌细胞中类异戊二烯酯的分析

类异戊二烯酯是细菌质膜的成分，在电子传递和氧化磷酸化中起重要作用。甲基萘酯和泛酯是其中较为重要的两类化合物。这两种化合物的分析鉴定是研究细菌细胞中类异戊二烯酯组成构象的前提，在细菌化学分类的研究中具有十分重要的意义。     

固相萃取-LC-MS定性分析微生物呼吸醌方法的建立

以UQ-6,UQ-10和Vitamin K1作为研究对象,建立了固相萃取LC-MS定性分析微生物呼吸甲基萘醌(MK-n(Hz))和泛醌(UQ-n(Hx))的方法,并用此法定性分析了厌氧活性污泥中的微生物呼吸醌,该方法具有选择性强、灵敏度高的优点,是一种非常有效的微生物种群分析方法。     

醌类图谱分析在环境微生物生态测定中的应用

近年来，随着人们对各种非培养微生物测定法的重视，醌类图谱分析作为微生物群体指标已在各种环境中得到了应用．首先是样品的分析测定技术得到了提高，如用硅胶柱代替薄层色谱．醌类图谱分析的特点是能够同时对应微生物生态评价的3个重要指标，即微生物群体结构、生物量及微生物多样性．在结合统计分析的基础上，在土壤、污泥及堆肥等不同环境样品及不同微生物反应过程中，已通过醌类图谱分析对这3个指标在微生物生态系中的变动进行了成功的评价．另外，对C-14同位素标记醌类图谱分析法及醌类图谱分析法在污染物降解中的应用等最新进展也进行了简介．图4表3参43     

城市大气颗粒物表面半醌自由基的测定及特征分析

采集上海市城区和郊区两个典型站位的大气颗粒物样品,通过二氯甲烷萃取分离并利用电子自旋共振波谱技术(ESR)分析测定吸附在颗粒物表面的稳定自由基.结果显示,测试样品的波谱特征表现为显著的三重信号峰,且g因子值均在2.00379—2.00395范围内,通过与醌类标准物质图谱比对,可以判断颗粒物表面至少吸附1种邻位半醌自由基.对自由基分布特征研究发现,自由基浓度的时空变化和粒径分布特征显著:闵行采样点的半醌自由基浓度远高于普陀采样点;在季节变化上表现为夏秋季半醌自由基浓度低于冬春季,其中春季最高,夏季最低;半醌自由基在不同粒径颗粒上的分布,呈现PM2.5>PM10>TSP的变化规律,说明自由基更容易富集在细颗粒上.     

嗜盐光合细菌的分离鉴定及其营养成分分析

从大连海岸的海泥中分离到 4株海洋光合细菌 :菌株C4 10、菌株DS2、菌株E3 和E4,它们都能在厌氧光照下营光异养生长 ,菌株C4 10还能够利用还原性硫化物营光自养生长 .依菌对NaCl的需求 ,菌株C4 10、DS2归属于嗜盐光合细菌 ,菌株E3 和E4属于耐盐光合细菌 .根据形态和培养特征、生理生化特征、光合作用内膜结构、泛醌组成、(G +C)的摩尔百分比等指标 ,菌株C4 10鉴定为Rhodovulumsulfidophilus (嗜硫小红卵菌 )、菌株DS2鉴定为Rhodobiummarinum (海红菌 )、菌株E3 和E4鉴定为Rhodobacterazotoformans.4株菌的营养成分分析表明 ,它们的细胞的最大生长量为 4× 10 9mL-1.粗蛋白含量占细胞干重的 5 5 %左右 ,菌株DS2高达 6 4 .2 % .4菌株所含氨基酸种类齐全 ,特别具备人和动物所必需的氨基酸 .4株菌均含有辅酶Q10和类胡萝卜素 .其中菌株C4 10的类葫萝卜素含量最高 .图 1表 6参 14     

亚麻温水脱胶液中细菌菌群结构分析

为了探讨实验室条件下模拟的工厂亚麻温水脱胶液中细菌菌群结构,采用纯培养技术和PCR-DGGE技术(Denaturing gradient gel electrophoresis)对细菌菌群结构进行了研究.用纯培养方法分离获得9类菌落,其中假单胞菌属(Pseudomonas)在有氧培养条件下总是处于优势.梭菌属(Clostridium)在厌氧培养过程中总是处于优势.微球菌属(Micrococcus)和葡萄球菌属(Staphylococcus)只有亚麻脱胶初期才有发现.PCR-DGGE指纹图谱显示,亚麻温水脱胶过程中条带数量较少且没有明显种群群落结构演替过程.通过对不同时期沤麻液中16S rDNAV3片段PCR产物d、e两个DGGE条带进行分子克隆、序列测定和Blas份析,发现e条带包含的16S rDNAV3片段除e 35外均属于假单胞菌属.d条带包含着较多不同的16S rDNAV3片段,其中有传统方法没有分离到的泛菌属(Pantoea)细菌、一些NCBI未收录的序列及一些非可培养微生物序列.纯培养技术和PCR-DGGE技术的共同使用,可以更全面准确地提供细菌多样性方面的信息.图4参15     

水葫芦内生细菌脂肪酸生物标记特性研究（Characteristics of PLFA Biomarkers for the Endophyte Bacteria inside Eichhornia crassipe（Mart.）Solms）

应用基于微生物细胞脂肪酸成分鉴定的全自动微生物鉴定系统,鉴定水葫芦内生细菌25株,分属15个属.共检测到27个脂肪酸生物标记(PLFAs),这些生物标记分为4种类型,即(1)高频次分布:在25株细菌中出现13～22次,属于细菌总体类群(general)的生物标记.(2)中频次分布:在25株细菌中出现5～7次,可以用于代表细菌属类群(genus)识别生物标记.(3)低频次分布:在细菌中的分布概率较小,可以用于指示特定细菌种间差异的生物标记.(4)微频次分布:仅在一种细菌种类出现,是细菌种(species)特征生物标记.利用脂肪酸生物标记分析同属细菌不同种的差异,可将微杆菌属分为2类,第1类包括菌株9Microbacterium barkeri和11Microbacterium imperiale,这两个菌株17:0ISO和14:0ISO的脂肪酸生物标记含量均为0.第2类包括10Microbacterium esteraromaticum、12Microbacterium lacticum和13Microbacterium liquefaciens,这3个菌株均含有17:0ISO脂肪酸生物标记而区别于第一类菌株.利用脂肪酸生物标记的差异对25株内生细菌进行聚类分析,可将水葫芦内生细菌类群分为4类.不同植物内生菌群落中存在着特异的生物标记,利用特征脂肪酸生物标记的分析方法,分析水葫芦内生细菌的群体特性,对于植物内生菌微生物群落的研究具有重要意义.     

戴安(DIONEX)园地离子色谱新进展

1 概述 离子色谱(IC)是高效液相色谱(HPLC)的一种，是分析离子的一种新的液相色谱方法.由于操作简便，对常见阴阳离子分析的高灵敏度，特别是对阴离子和价态形态分析的突出优点，已广泛应用于环境、电厂、半导体、食品卫生、石油化工和生命科学等领域［1］.世界著名色谱学家G.Guiochon认为，近30年来气相色谱(GC)和高压液相色谱(HPLC)取得了辉煌成就.在GC和HPLC中，HPLC是应用最广泛，发表文献最多的一个领域.1997年后，以6—8％的速度递增，其中离子色谱是最活跃的领域之一. 离子色谱作为实验室中常规分析手段，近几年发展的趋势主要集中在以下几方面：高性能的分离柱和抑制器的研究；减少人为误差，提高自动化程度；离子色谱分析方法成为国家、各行业中某些项目特别是阴离子“标准分析方法”的数量不断增加；增加数据容量和数据集中管理使用.本文着重讨论第一方面的进展［2］.     

大骨节病病区饮用水中有机物的初步鉴定

对大骨节病区及非病区饮用水,用树脂吸附法富集其中的有机物并进行GC-MS分析。结果发现,所有样品的主要成分为各种脂肪和芳香烃类及含氧、硫、氮的化合物。病村饮水中鉴定出较高浓度的醌酚类化合物,表明这两类化合物对大骨节病病因的研究确实是不可忽视的因素。     

致癌性卤代醌介导的脂质氢过氧化物分解的分子机制

卤代醌是许多卤芳香持久有机污染物的致癌代谢产物和饮用水消毒副产物.13-过氧羟基-9,11-十八碳二烯酸(13-HPODE)是最为广泛研究的内源性脂质过氧化物.众所周知,过渡金属离子可以催化分解13-HPODE,但尚不清楚卤代醌是否可以通过不依赖金属离子的途径促进其分解;若是如此,又有什么特异性和相似性?我们发现卤化醌如2,5-二氯-1,4-苯醌(DCBQ)可显著促进13-HPODE的分解.综合采用电子自旋共振-自旋捕获、HPLC-MS和GC-MS等分析方法,可检测到反应形成的脂质烷基自由基如戊烷基自由基、7-羧甲基自由基以及具有基因毒性的4-羟基-2-壬烯醛(HNE)等.在DCBQ和13-HPODE的反应中也能检测到两种氯醌-脂质烷氧基耦合物.我们认为卤代醌促进内源性脂质过氧化物13-HPODE分解生成活性脂质烷基自由基和基因毒性的HNE是通过一类新型的金属非依赖亲核取代与裂解机理来实现的,这也在一定程度上解释了其潜在的基因毒性和致癌性.     

Structural confirmation of the sea ice biomarker IP25 found in Arctic marine sediments

IP₂₅ is a highly branched isoprenoid and an organic geochemical biomarker that is produced by some Arctic sea ice diatoms. IP₂₅ has previously been used in Arctic palaeo sea ice reconstruction studies and as a tracer for studying Arctic food webs. Here, the molecular structure of IP₂₅ has been confirmed by ¹H and ¹³C NMR spectroscopy following large-scale extraction from marine sediments obtained from the Canadian Arctic and purification using a combination of open-column and HPLC chromatographic methods. The structure of IP₂₅ was consistent between the three different sampling locations and was identical to that found previously for this biomarker following synthesis from a closely related highly branched isoprenoid diene. Since this study represents the first structural characterisation of IP₂₅ in sediments, future analysis of sedimentary IP₂₅ for palaeo Arctic sea ice reconstructions can be carried out with much greater confidence.     

The determination of partition coefficients of organic compounds in technical products and waste waters for the estimation of their bioaccumulation potential using reversed phase thin layer chromatography

Reversed phase thin layer chromatography (RPTLC) has been investigated for the estimation of octanol/water partition coefficients (P), an important parameter for the prediction of the environmental behaviour of organic chemicals. A strong correlation between P derived from the traditional octanol/water system and RPTLC has been established over five orders of magnitude. RPTLC data are likewise correlated to results obtained by high performance chromatography (HPLC). Due to the low costs, simplicity and separation power RPTLC is especially suited for the investigation and screening of mixtures of compounds before more complicated tests are involved.

Results from a round robin test on the determination of partition coefficients by HPLC, RPTLC and the batch method indicate the simplicity and accuracy of the RPTLC technique. Applications of the RPTLC‐technique on technical products and industrial waste waters are described.     

Comparison of various sensitive and selective spectrophotometric assays of environmental cyanide

A simple approach was carried out to study the effects of various parameters on high performance liquid chromatography (HPLC) performance of microcystin-LR (MC-LR) analysis in samples from some reservoirs and rivers in Taiwan under simulation conditions. Nature of column and its packing affected the instrument sensitivity. Varied column length indicated the longer column enhanced (C18, 5 μm, 4.6 × 150 mm) HPLC performance. Studies on mobile phase found that ratio and concentration of the mobile phase gradient greatly influenced the peak shape, retention time, and optimal conditions of mobile phase were set at acetonitrile and 0.01M ammonium acetate (30:70). Different compounds were added to mobile phase and their contribution to HPLC spectra was reported. Detection limits were carefully measured and reported. These investigations provide simple and important information that may be applied to HPLC performance for microcystin analysis from natural water systems.     

环境分析化学中化学发光分析的研究与应用

对2000年以来化学发光分析在环境污染物分析中的应用研究进行了评述,其中,包括与化学发光分析联用的流动注射、高效液相色谱和毛细管电泳技术等.     

Isolation and characterization of naturally and artificially induced hepatic metallothioneins from two species of flatfish: Limanda limanda and Microstomus kitt

The separation of hepatic metallothioneins of Limanda limanda and Microstomus kitt by gel-filtration chromatography, anion-exchange high-performance liquid chromatography (HPLC) and reversed-phase HPLC is described. Two isoforms of metal-binding proteins were isolated by DEAE HPLC chromatography from fish caught in the field and fish injected intraperitoneally with Cd. The amino acid composition of these proteins further purified by reversed-phase HPLC chromatography revealed the existence of metallothioneins. The route of contamination (natural or artificial) of the fish has no effect on the nature of these proteins and one of the two protein isoforms from each species has similar ionic properties.     

麻疯树种子中佛波酯的提取及对菜青虫的杀虫活性

佛波酯是麻疯树种子中的主要毒性物质之一.麻疯树种子经乙醇浸提、液液萃取和柱层析,获得佛波酯富集物.以TPA为外标,通过高效液相色谱(HPLC)定量分析佛波酯的含量,同时检测其对菜青虫的毒杀和拒食活性.结果显示,富集物中佛波酯含量达到0.817 35 mg mg-1.佛波酯富集物对3龄菜青虫具有显著的毒杀和拒食活性:毒杀活性表现为胃毒作用,胃毒活性具有明显的剂量效应和时间效应,48、72、120 h的佛波酯半致死浓度(LC50)分别为73.86、16.99、5.26μg mL-1;24、48 h的非选择拒食中浓度(AFC50)分别为9.81、5.39μg mL-1.图3表3参24     

Determination of 4-nonylphenol in carp blood samples by solid phase extraction and chromatographic techniques

In this study, selective methods were developed for isolation, purification, separation and determination of 4-nonylphenol (4NP) in biological samples. Several methods such as high-performance liquid chromatography (HPLC) with fluorescence and diode array detection and gas chromatography coupled to mass spectromotry (GC-MS) are described for the simultaneous determination of 4NP. The nonylphenols in the plasma of fish were extracted through solid phase process by using octadecyl, polymeric and octadecyl endcapping sorbents. The average recoveries in plasma samples spiked with 4NP of levels 1?µg?mL^?1 were between 80–95% using added surrogate standards. The aim of this study was to determine whether trace amounts of 4NP in fish plasma samples could be detected by solid phase extraction and chromatographic methods (HPLC, GC-MS). This technique of monitoring the levels of endocrine-disruptors in plasma samples is consistent, reliable as well as inexpensive.     

Involvement of quinones and phenoloxidase in the allorejection reaction in a colonial ascidian, Botrylloides simodensis: histochemical and immunohistochemical study

When incompatible colonies of Botrylloides simodensis were brought into contact at their artificially cut surfaces, allorejection occurred and a black line was formed along the contact border. Morula cells (MCs), a type of hemocytes, are the major effector in the allorejection reaction and are known to possess phenoloxidase (PO) that generates quinones. In this rejection reaction, MCs infiltrate the tunic and break down, discharging their vacuolar contents. Ascorbic acid (antioxidant) and benzamidine (protease inhibitor) showed inhibitory effects on MC breakdown, black line formation and new tunic cuticle formation, whereas tropolone (metal chelator) and sodium benzoate (substrate analog) did not. MCs probably store some amount of quinones, as well as PO; oxidants derived from the quinones appear to disintegrate the tissue to form a black line and promote MC breakdown. Histochemical and immunohistochemical studies revealed that MCs contain eosinophilic materials, PO and quinones. Quinones that are stored in MCs and produced by PO probably have a destructive function, forming rejection lesions.     

植物中的褪黑激素:含量、检测方法与功能

近年来发现褪黑激素不仅存在于动物中,而且在植物尤其是药用植物和食用植物中也普遍存在.目前国外对植物中的褪黑激素研究比较关注,国内仅有个别报道.本文综述了截止目前国内外对植物中褪黑激素含量与功能的研究进展,同时也介绍了褪黑激索的测量方法等.检测褪黑激素的方法有HPLC(高效液相法),RIA(放射免疫测定),LC-MS(液相色谱-质谱),GC-MS(气相色谱-质谱)等方法.褪黑激素在植物中有许多重要功能,如抗自由基抗氧化,促进植物生长和影响短日照植物开花,促进果实成熟以及抑制细胞程序性死亡等.因此研究褪黑激素在植物中的含量和功能对人们的生产生活具有较大的实际意义.最后讨论了植物中褪黑激素研究及其在农业生产中应用的前景.表1参41     

Atrazine and mancozeb induce excitotoxicity and cytotoxicity in primary cultures of mouse cerebellar cortex

This work aimed to determine the neurotoxicity of atrazine and mancozeb by high performance liquid chromatography (HPLC) evaluation of neurotransmitters, and morphologically by flow cytometry and ultrastructural analysis using transmission electron microscopy of primary cultures of mouse cerebellar cortex. The latter revealed mitochondrial damage, synaptic alterations, and neuroinflammation, while neurochemical results showed augmented release of excitatory neurotransmitters with a consequent increase in excitation/inhibition ratio of atrazine- and mancozeb-treated cultures. This study shows that atrazine and mancozeb exposure may lead to neuronal damage associated with excitotoxicity and cytotoxicity.