反相离子对色谱分析水稻愈伤组织中的内源生长素

本文用反相离子对色谱技术定量分析了水稻愈伤组织中的内源生长素５０Ｈ－１ＡＡ和１ＡＡ，样品用８０％丙酮－ＢＨＴ－抗坏血酸抽提，经ＤＥＡＥ纤维素柱和ＸＡＤ－７吸附树脂柱净化和富集，在Ｌｉｃｈｒｏｓｏｒｂ ＲＰＣ１８柱上分离，荧光检测。最低检出限：１ＡＡ为８０ｐｇ，５０Ｈ－ＩＡＡ为０．３ｎｇ。回收率为８５．５％～７３．３％，相对标准偏差为２．２％。文中还对ｐＨ值和离子对试剂对保留值的影响，进行了讨论，对     

气相色谱法测定化妆品中的 VE 含量

介绍了一种用气相色谱法准确快速测定品中ＶＥ２含量的新方法。该法以ＶＣ作保护剂,用环已烷提取样品,ＳＥＰ－ＰＡＫ ＡＬＵＭ－Ａ小柱净化。以氯氰菊酯内标物,在１？５％ＯＶ＝－１７色谱柱上进行分离,测定化妆口中ＶＥ含量。内标物与样品的分离度为１．５５。平均回收纺为９４．３％～９８．８％,相对标准偏差为１．７％～３．５％（ｎ＝５）。     

二乙氨乙基交联葡聚糖和季氨基琼脂糖色谱分离植物脂多糖的比较

比较了应用Q Sepharose Fast Flow凝胶和DEAE-Sephadex A50凝胶柱色谱分离米糠提取物中米糠脂多糖(LPSR)的效果。结果表明：通过改变体系的离子强度，两凝胶都可使LPSR与一般多糖分离，但仅Q Sepharose Fast Flow柱色谱可实现LPSR与米糠色素的有效分离，并获得淡黄色、99．5％纯度的LPSR产品，而且耐盐性能好于DEAE-Sephadex A50。     

以交联聚乙烯醇为载体的离子交换剂对蛋白质的分离性能

本文对阴离子交换剂ＤＥＡ—ＰＶＴ常压液相离子交换色谱分离蛋白质的性能、分离条件进行了探讨。结果表明其对蛋白质的分离性能良好，容易洗脱。与载体交联聚乙烯醇相比，ＤＥＡ—ＰＶＴ对蛋白质的非特异性吸附明显降低。     

高效液相色谱和高效液相色谱—质谱法测定粮食中互隔交链孢霉醇,互隔交…

建立了粮食中互隔交链孢霉醇，互隔交链孢霉醇单甲醚和玉米赤烯酮三个毒素的ＨＰＬＣ定性定量分析法和粒子束ＬＣ－ＭＳ／ＥＩ＾＋鉴定方法，采用反相色谱，以８０％的甲醇水溶液作流动相，这三个毒素在Ｃ１８色谱柱上彼此间均获得较好的分离，方法对粮食中ＡＯＨ，ＡＭＥ两个毒素的回收率均在７９％以上，ＡＯＨ，ＡＭＥ两个毒素的最低检出限为１×１０＾－９ｇ。用所建立方法对１００多个大骨节病病区，非病区的粮食样品进行了检测     

高效离子交换液相色谱法分离绿脓杆菌外膜蛋白

利用高效ＤＥＡＥ离子交换液相色谱法分离纯化了绿脓杆菌标准菌株ＰＡＯ１外膜蛋白。流动相为ｐＨ８．０Ｔｒｉｓ－ＨＣｌ缓冲液,色谱柱为ＴＳＫｇｅｌ－ＤＥＡＥ－５ＰＷ（０．７５ｃｍ×７．５ｃｍｉ．ｄ．）。通过纯化外膜蛋白,可以为研究绿脓杆菌外膜通透性与抗生素耐药性之间的关系及缩短研究周期提供有效的方法。     

吸附固定相电色谱和动态改性电色谱的手性分离

对动态改性电色谱手性分离进行了研究。电色谱柱填充强阴离子交换固定相（SAX0,添加在流动相中的磺化β－环糊精（S－CD）动态地吸陵于SAX填料表面,形成一层准手性固定相。色氨酸、阿托品和异博定对映体在本体系获得了很好的分离,它们的分离分别为2．06,10．1和1．96,对映体峰的柱效价于85,000塔板数／米和412,000塔板数／米之间。连续运行17次,死时间和色氨酸对映体的电色谱保留因子的相对标准偏差分别为0．53％,0．62％和0．69％。此外,以吸附于SAX填料的牛血清白蛋白和S－CD为手性固定相进行了电色谱手性分离的研究。在这两种体系下分离色氨酸对映体的分离度分别为3．86和2．97。吸附S－CD柱电色谱和动态改性电谱的重现性进行子比较,发现动态改性电色谱有更好的重现性。     

肝素亲和柱与高效液相柱二步色谱法分离基因重组的人血小板第四因子

介绍利用肝素亲和色谱和高效液相色谱二步法分离纯化基因重组的人血小板第四因子（ｒｈＰＦ４）。采用肝素柱，用含不同浓度的ＮａＣｌ的磷酸盐缓冲液（ｓｏｄｉｕｍｐｈｏｓｐｈａｔｂｕｆｅｒ，即ＰＢＳ）（２０ｍｍｏｌ／Ｌ，ｐＨ７．４）分级洗脱，得到初步纯化的ｒｈＰＦ４（纯度达８０％）；再采用Ｃ１８柱，乙腈（含０．１％三氟醋酸即ＴＦＡ）－水（含０．１％ＴＦＡ）为流动相梯度洗脱，得到进一步纯化的产物。方法快速、准确、分离效果好，经过两次分离后产物纯度达９５％以上。     

肝素亲和柱与高效液相柱二步色谱法分离基因重组的人血小板第四因子

 介绍利用肝素亲和色谱和高效液相色谱二步法分离纯化基因重组的人血小板第四因子（ｒｈＰＦ４）。采用肝素柱，用含不同浓度的ＮａＣｌ的磷酸盐缓冲液（ｓｏｄｉｕｍｐｈｏｓｐｈａｔｂｕｆｅｒ，即ＰＢＳ）（２０ｍｍｏｌ／Ｌ，ｐＨ７．４）分级洗脱，得到初步纯化的ｒｈＰＦ４（纯度达８０％）；再采用Ｃ１８柱，乙腈（含０．１％三氟醋酸即ＴＦＡ）－水（含０．１％ＴＦＡ）为流动相梯度洗脱，得到进一步纯化的产物。方法快速、准确、分离效果好，经过两次分离后产物纯度达９５％以上。     

离子交换法纯化重组类人胶原蛋白Ⅱ的研究

用阳离子交换树脂CM-52分离纯化类人胶原蛋白Ⅱ（Human Collagen-like Bioprotein Ⅱ，HCBⅡ）。通过实验，分别确定了静态吸附和柱层析吸附的操作条件，即静态吸附：在pH4．0、NaCl0．15mol／L、进料浓度7g／L，处理量17．26ml／g树脂的条件下进行吸附，吸附时间为60min；柱层析：在pH4．0、NaCl0．15mol／L、进料浓度5g／L、流速5ml／min的条件下进行吸附。然后上柱，在pH4．0、NaCl0．30mol／L下进行脱附。实验表明，采用静态吸附的方式吸附HCBⅡ，然后上柱洗脱，HCBⅡ的吸附量可达到48、6mg／g树脂，回收率83．8％，操作时间短，分辨率高，最终纯化的HCBⅡ达电泳纯，分子量为97kD。     

lux-marked Pseudomonas aeruginosa lipopolysaccharide production in the presence of rhamnolipid

Rhamnolipid produced by Pseudomonas aeruginosa during the late logarithmic growth phase has been reported to be an effective biosurfactant. In the presence of rhamnolipid, P. aeruginosa had a higher specific lipopolysaccharide production, which was attributed to the increase of carbon to nitrogen ratios owing to the increase of the solubility of hydrophobic hydrocarbons, favoring the synthesis of lipopolysaccharides. P. aeruginosa also had a higher ratio of lipopolysaccharides in the growth medium to those on cell surfaces than in the absence of rhamnolipid because the presence of rhamnolipid stimulated the release of lipopolysaccharides from P. aeruginosa cell outer membranes. The release of lipopolysaccharides from cell surfaces made P. aeruginosa exhibit a more hydrophobic surface, enhancing the accumulation of hydrophobic hydrocarbons on P. aeruginosa cell surfaces and consequently resulting in a higher growth rate.     

Gas chromatographic determination of (phosphorylated) 2-keto-3-deoxyoctonic acid, heptoses and glucosamine in bacterial lipopolysaccharides after treatment with hydrofluoric acid, methanolysis and trifluoroacetylation

Quantification of phosphorylated sugar constituents of lipopolysaccharides has been performed by the following sequence: dephosphorylation by treatment with hydrofluoric acid, cleavage to monomeric constituents by methanolysis and analysis of the released sugars by capillary gas chromatography. Lipopolysaccharides of Salmonella minnesota Rd1P+, Bordetella pertussis NIH 114 and Vibrio cholerae, NAG and 95R strains, were used as model substances. Comparison of the chromatographic data obtained from hydrofluoric acid-treated and untreated lipopolysaccharide preparations indicated that all lipopolysaccharides examined contained one moiety of glucosamine bound to phosphate in a stable linkage. 2-Keto-3-deoxyoctonic acid appeared phosphorylated to a variable extent. Lipopolysaccharides of the two V. cholerae strains contained one moiety of fully phosphorylated 2-keto-3-deoxyoctonic acid, whereas in that of S. minnesota Rd1P+ only one of the three moieties was phosphorylated. Lipopolysaccharide of B. pertussis had one moiety of 2-keto-3-deoxyoctonic acid, ca. 70% phosphorylated. All four of the preparations examined contained L-glycero-D-manno-heptose in amounts varying from 2.6 to 5.2 moieties. In the lipopolysaccharides of B. pertussis and strain 95R of V. cholerae this sugar was unphosphorylated, whereas the two remaining strains contained one phosphorylated moiety of this sugar. Phosphorylated lipopolysaccharide constituents can be analysed by this approach on a 50-100 micrograms scale.     

Cloning,High Expression and Purification of Recombinant Human Intereferon-β-1b in <Emphasis Type="Italic">Escherichia coli</Emphasis>

Sequential evaluation and process control strategy were employed for impurity profile and high recovery with quality of rhIFN-β-1b expressed in Escherichia coli. The high-level expression was achieved by using codon substitution (AT content of 52.6% at N-terminal region) and optimization of culture conditions. The addition of rifampicin at a concentration of 200 μg/ml has increased the specific product yield of 66 mg optical density⁻¹ l⁻¹ (43.5% of total cellular protein). Eighty-three percent of lipopolysaccharides, 32% of host deoxyribonucleic acid (DNA), and 78% of host cell proteins were removed by 0.75% Triton X-100 and 2 M urea wash. Eleven percent of lipopolysaccharides, 39% of host DNA, and 12% of host cell proteins were removed at the solubilization step. Ninety-two percent of protein refolding was achieved by high-pressure diafiltration method. Refolding by high-pressure diafiltration, bed height, and height equivalent to the theoretical plate value in chromatography column were identified as key parameters for high recovery with purity. Finally, the established process yielded 34% of purified protein with greater than 99% purity and is acceptable for preclinical toxicological studies. The purified rhIFN-β-1b obtained in this study is the highest that has been reported so far.     

Comparative structural study of the lipopolysaccharides of Y. enterocolitica serovars 0:7.8 and 0:19.8

The lipopolysaccharides ofYersinia enterocolitica, serovars 0:7.8 (strain 106) and 0:19.8 (strain 842), isolated from the microbial mass by phenol-water extraction, contained residues of L-fucose, 6-deoxy-D-gulose, D-mannose, D-galactose, D-glucose, D- and L-glycero-D-mannoheptoses, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, and 2-keto-3-deoxyoctonic acid (KDO). The polysaccharides obtained by mild acid hydrolysis of the lipopolysaccharides followed by gel filtration on Sephadex G-50 were a mixture of the O-specific polysaccharide and the core, which could not be separated even by repeated rechromatography because of the comparability of their molecular masses. On the basis of the results of monosaccharide analysis, methylation, Smith degradation, and partial hydrolysis, a structure has been suggested for the repeating unit of the O-specific polysaccharides of the lipopolysaccharides ofY. enterocolitica of the serovars studied.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, USSR Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 763–770, November–December, 1989.     

Recent results on the biochemistry of the cell wall lipopolysaccharides of Salmonella bacteria

Lipopolysaccharides, which are located in the cell wall of gram-negative bacteria, are characterized by their biological versatility. They represent the O antigens of the bacteria, they are potent endotoxins, and they often function as the receptor sites for bacteriophages. The study of the mode of action of lipopolysaccharides and the search for structures in the macromolecules that are responsible for biological activity became promising when principles of the chemical fine structure of lipopolysaccharides were identified. The following review summarizes the results of recent investigations regarding the structure of lipopolysaccharides, their biosynthesis and its genetic determination.     

Comparative structural study of the lipopolysaccharides of Y. enterocolitica serovars 0:7.8 and 0:19.8

The lipopolysaccharides ofYersinia enterocolitica, serovars 0:7.8 (strain 106) and 0:19.8 (strain 842), isolated from the microbial mass by phenol-water extraction, contained residues of L-fucose, 6-deoxy-D-gulose, D-mannose, D-galactose, D-glucose, D- and L-glycero-D-mannoheptoses, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, and 2-keto-3-deoxyoctonic acid (KDO). The polysaccharides obtained by mild acid hydrolysis of the lipopolysaccharides followed by gel filtration on Sephadex G-50 were a mixture of the O-specific polysaccharide and the core, which could not be separated even by repeated rechromatography because of the comparability of their molecular masses. On the basis of the results of monosaccharide analysis, methylation, Smith degradation, and partial hydrolysis, a structure has been suggested for the repeating unit of the O-specific polysaccharides of the lipopolysaccharides ofY. enterocolitica of the serovars studied. Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, USSR Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 763–770, November–December, 1989.     

Photodegradation of lipopolysaccharides and the inhibition of macrophage activation by anthraquinone-boronic acid hybrids

Target-selective photodegradation of 3-deoxy-D-manno-2-octulopyranosonic acid (KDO) was achieved without additives and under neutral conditions using a designed anthraquinone-boronic acid hybrid and long wavelength UV light irradiation. The hybrid can photodegrade lipopolysaccharides (LPS) and inhibit macrophage activation induced by LPS.     

Spectrophotometric determination of a bacterial lipopolysaccharide fromEscherichia coli 675

A method has been developed for the quantitative spectrophotometric determination of the lipopolysaccharides ofE. coli 675. The maximum absorption of the lipopoly-saccharides fromE. coli 675 (259 nm) coincides with the maximum absorption (259 nm) of a number of polysaccharides from other Gram-negative bacteria, which can be used to determine lipopolysaccharides in various media.     

Low frequency electric polarizability and zeta-potential of Escherichia coli HB101 (K-12) cells during inactivation with ethanol

The electric properties of bacteria determine their non-specific interactions with the environment, in particular their pathogenic activity. The electric polarizability of Escherichia coli HB101 (K-12 strain) was studied while inactivation with ethanol (20–40 vol.%). The current investigation might be regarded as a continuation of previous research on the polarizability of E. coli at lower ethanol concentration (≤ 20 vol.%) and higher frequencies (≥ 20 kHz). The bacteria polarizability at low frequencies (<10⁴ Hz) shows anomalies (unexpected increase in the polarizability at certain ethanol concentrations), while the parameter decreases with an increase in the ethanol concentration at higher frequencies. We investigated for the possible reasons causing the anomalies — in our case reduced to the medium dielectric permittivity, the average cell length and the surface electric charge density distribution, related to bacterial lipopolysaccharides. We suggest a hypothesis for the molecular mechanism of changing the surface charge of E. coli, carried by lipopolysaccharides, induced by the non-ionic ethanol.