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1.
异养细胞种子/光自养培养方法是一种可异养培养的能源微藻培养的有效方法,但已有文献尚未从工艺优化角度考察其发展潜力。为了获得较高细胞密度的用于光自养培养的种子和提高光自养培养的细胞密度与油脂产率,对异养细胞种子/光自养培养的培养基和培养条件进行了优化。结果表明,采用优化后的培养基,椭圆小球藻在摇瓶中异养培养的最高藻细胞密度可达11.04 g/L,比在初始培养基条件下提高了28.0%,在5 L发酵罐中异养培养的藻细胞密度达到73.89 g/L;在2 L柱式光生物反应器中光自养培养的藻细胞密度、油脂含量和油脂产率分别达1.62 g/L、36.34%和6.1 mg/(L·h),油脂成分主要为含C16-C18碳链的脂肪酸,是制备生物柴油的理想原料。经过优化,异养细胞种子/光自养培养这一方法能够显著地提高椭圆小球藻产油脂的能力,这进一步表明异养细胞种子/光自养培养方法有望成为可异养的能源微藻的高效培养方式。  相似文献   

2.
The distribution of choline oxidase activity was studied with cell-free extracts of yeasts, molds and actinomycetes. A fungus which was identified as Cylindrocarpon didymum M–1 showed the highest activity. The enzyme was purified from the cell-free extract of C. didymum M–1 by a procedure involving ammonium sulfate fractionation and DEAE-cellulose, hydroxyl-apatite and Sephadex G–150 column chromatographies. The enzyme preparation was homogeneous when subjected to disc gel electrophoresis and ultracentrifugation. Sedimentation velocity yielded a value of . The enzyme showed a typical flavoprotein spectrum of absorption maxima at 276,370 and 454 nm.  相似文献   

3.
Molecular networking approach was applied for the targeted isolation of new sterigmatocystin derivatives, sterigmatocystins A–C, from the marine sponge‐derived fungus Aspergillus versicolor. Sterigmatocystin A features a rare 6/6/6/6/5 polycyclic system. The structures of sterigmatocystins A–C, including absolute configurations, were determined on the basis of spectroscopic data and ECD calculations. Sterigmatocystin A showed more stronger promoting angiogenesis activity than the positive control at 1.25 μM level in transgenic fluorescent zebrafish. Sterigmatocystins A–C also exhibited moderate antiviral activity by the inhibition of HSV‐2.  相似文献   

4.
植物中来源于甘氨酸和丝氨酸的一碳单位转移给四氢叶酸用于四氢叶酸代谢物的生物合成.由于含量低、成份复杂以及稳定性差,植物组织中四氢叶酸代谢物和叶酸的定量分析一度是一个挑战性很强的课题.本研究旨在建立一种可靠方法测定对甲基基团要求不同的植物(例如累积甘氨酸甜菜碱的菠菜与不累积甘氨酸甜菜碱的拟南芥)中四氢叶酸代谢物和叶酸的含量,用于研究这些植物中通过叶酸途径的一碳单位通量.菠菜和拟南芥叶片在金色荧光灯下加液氮研磨,加入大鼠血浆轭合酶粗提物处理,提取物经叶酸结合蛋白琼脂糖亲和色谱柱纯化,用附有荧光和紫外检测器的高效液相色谱仪分离并测定四氢叶酸代谢物和叶酸的含量.菠菜和拟南芥叶片中单谷氨酸型N5-甲基四氢叶酸含量分别是252ng/g和64ng/g,而总N5-甲基四氢叶酸的含量分别是370ng/g和199ng/g.两种植物均检测到少量的四氢叶酸和N5-醛基四氢叶酸,但只在拟南芥叶片而非菠菜叶片中检测到叶酸.实验结果显示,菠菜中单谷氨酸型和多谷氨酸型N5-甲基四氢叶酸的含量均比拟南芥显著增多.这种样品制备和高效液相色谱方法适于测定植物中四氢叶酸代谢物和叶酸的含量.  相似文献   

5.
A chemical investigation of the endolichenic fungus Aspergillus versicolor (125a), which was found in the lichen Lobaria quercizans, resulted in the isolation of four novel diphenyl ethers, named diorcinols F–H ( 1 – 3 , resp.) and 3‐methoxyviolaceol‐II ( 4 ), eight new bisabolane sesquiterpenoids, named (?)‐(R)‐cyclo‐hydroxysydonic acid ( 5 ), (?)‐(7S,8R)‐8‐hydroxysydowic acid ( 6 ), (?)‐(7R,10S)‐10‐hydroxysydowic acid ( 7 ), (?)‐(7R,10R)‐iso‐10‐hydroxysydowic acid ( 8 ), (?)‐12‐acetoxy‐1‐deoxysydonic acid ( 9 ), (?)‐12‐acetoxysydonic acid ( 10 ), (?)‐12‐hydroxysydonic acid ( 11 ), and (?)‐(R)‐11‐dehydrosydonic acid ( 12 ), two new tris(pyrogallol ethers), named sydowiols D ( 13 ) and E ( 14 ), and fifteen known compounds, 15 – 29 . All of the structures were determined by spectroscopic analyses, and a number of them were further identified through chemical transformations and electronic circular dichroism (ECD) calculations. Preliminary bioassays of these isolates for the determination of their inhibitory activities against the fungus Candida albicans, and their cytotoxicities against the human cancer cell lines PC3, A549, A2780, MDA‐MB‐231, and HEPG2 were also evaluated.  相似文献   

6.
目的:利用HPLC-MS/MS方法对十种一碳代谢相关产物进行定量分析。方法:采用Aglient ZORBAX SB-AQ C18柱(2.1mm×100 mm,3.5 m)、电喷雾离子源(ESI),以多离子反应监测方式(MRM)进行正离子检测。对游离叶酸(FA)、5-甲酰四氢叶酸(5-FT)、5-甲基四氢叶酸(5-MT)、S-腺苷蛋氨酸(SAM)、S-腺苷同型半胱氨酸(SAH)、胱硫醚(CYSTA)、组氨酸(HIS)、丝氨酸(SER)、蛋氨酸(MET)、同型半胱氨酸(HCY)进行定量分析。结果:FA、5-FT、5-MT、SAM、SAH、CYSTA、HIS、SER、MET、HCY的检测限分别为0.1 ng.L-1、0.25 ng.L-1、0.1 ng.L-1、0.1 ng.L-1、0.25 ng.L-1、0.25 ng.L-1、0.1 ng.L-1、0.025 ng.L-1、0.1 ng.L-1、0.1 ng.L-1。FA、5-FT、5-MT、SAH、CYSTA浓度测定方法线性范围为2~50 ng.L-1,SER、SAM浓度测定方法线性范围20~500 ng.L-1,MET、HCY浓度测定方法线性范围200~5000 ng.L-1,HIS浓度测定方法线性范围为400~10000 ng.L-1,r均在0.993以上,全部涵盖了已报道的血清中指标的含量范围。结论:建立了HPLC-MS/MS方法,可同时分析十种一碳代谢通路的关键产物,所需样品量少,检测速度快,同时实现分项检测,可为多种代谢性疾病系统性地检测一碳代谢中间产物体液分析方法建立实验条件基础。  相似文献   

7.
MAPELLI  S.; ROCCHI  P. 《Annals of botany》1983,52(3):407-409
A technique for the separation and quantitative estimation ofabscisic acid and its metabolic products, phaseic acid and dihydrophaseicacid by high performance liquid chromatography (HPLC) is described.The efficiency of two HPLC columns, LiChrosorb RP-18 and LiChrosorbNH2 is compared. The method has been tested using extracts fromtomato plants and some of the results are presented. Abscisic acid, dihydrophaseic acid, phaseic acid, chromatography, tomato, Lycopersicon esculentum, Mill  相似文献   

8.
高效液相色谱法测定辣椒素   总被引:1,自引:0,他引:1  
用95%醋酸钠饱和乙醇溶液抽提辣椒树脂油中的辣椒素,经高效液相色谱(HPLC)分离,在紫外波长280 nm处测定。用此法分析测得福建特产"小米椒"的辣椒素含量为10.38%。  相似文献   

9.
A method is presented for separation of tryptic glycopeptides-containing oligosaccharides of the N-asparagine-linked type. High performance liquid Chromatography (HPLC) of glycopeptides on a C18 reverse-phase system eluted with a gradient of 0%–50% acetonitrile in 0.1 M NaPO4 pH 2.2 resolves the two major glycosylation sites from the envelope glycoprotein (G) of vesicular stomatitis virus. Glycopeptides containing N-linked oligosaccharides of the complex type coelute with those containing N-linked oligosaccharides of the neutral, high mannose type, indicating that separation is based upon peptide rather than carbohydrate composition. The contribution of the carbohydrate component to glycopeptide elution, as determined by cleavage of the high mannose oligosaccharides with endo-β-Nacetylglucosaminidase H, is that of a significant, but minor, decrease in peptide retention time. Comparison of the tryptic glycopeptide profiles of G isolated from both wild type and mutant strains of VSV illustrates the rapid, reproducible, and quantitative nature of the technique. Through HPLC analysis of appropriately treated glycopeptides, it is possible to explore both the nature and extent of glycosylation at individual sites in glycoproteins in a single step.  相似文献   

10.
高效液相色谱法测定超滤后血浆中的谷氨酰胺   总被引:13,自引:0,他引:13  
用高效液相色谱法测定超滤后血浆中的谷氨酰胺, 平均回收率为96.75%, 在130~1300μmol/L范围内呈线性关系(r=0.9906), 健康人正常值男性为(694.97±102.31)μmol/L, 女性为(623.79±99.27)μmol/L, 男女间值有显著差别(P<0.05)该分析方法简单、迅速, 可用于外科肠道内营养的监测和对肠粘膜结构与功能的研究.  相似文献   

11.
高效亲和膜色谱快速分析及小量制备蛋白质   总被引:3,自引:0,他引:3  
以甲基丙烯酸缩水甘油酯纤维素复合膜为基质,分别以蛋白A(Protein A)、人免疫球蛋白G(HIgG)、三嗪染料(Cibacron blue F3GA)、亚胺二乙酸铜离子为配基,用不同方法制备了适合于分析及小量制备的高效亲和膜色谱介质,并对高效亲和柱的基本性能及其应用于各种相应蛋白的定量测定情况进行了考察。利用这种方法可以针对不同的目标蛋白及所存在的环境采用不同的配基,对各种蛋白的定量测定及小量制备可达到较为满意的结果。  相似文献   

12.
利用高速逆流色谱对大黄中的5个蒽醌活性成分进行了分离,当两相溶剂系统的组成是石油醚∶乙酸乙酯∶甲醇∶水=8∶2∶8∶1时,分离出大黄素;当两相溶剂比为3∶4∶3∶2时,分离出大黄酸和芦荟大黄素;当溶剂比为12∶2∶12∶1时,分离出大黄酚和大黄素甲醚;经高压液相色谱检测大黄素、大黄酸和芦荟大黄素、大黄酚和大黄素甲醚的含量分别为98.81%9、9.15%、98.51%9、8.89%和98.16%。  相似文献   

13.
以米曲霉(Aspergillus oryzae)RIB40基因组DNA为模版,通过PCR扩增其烯酮烯酯还原酶(AspER)基因(asper)后连接到表达载体pET32a(+)上,在大肠杆菌BL21(DE3)中以可溶形式表达。通过Ni-NTA亲和色谱层析纯化后,蛋白纯度提高1.9倍,回收率为60.62%。根据分子筛凝胶层析结果推算,AspER以二聚体形式存在。性质分析表明此酶为依赖于NADPH的氧化还原酶,最适pH为7.0~8.0,最适温度为40℃。对2-环己烯酮Km和kcat值分别为(2.45±0.36)mmol/L和(4.4±0.4)×103s-1。底物谱分析发现AspER对马来酰亚胺及其衍生物有较高的活性,其中对2-甲基马来酰亚胺的转化率和e.e.值均高于99%。  相似文献   

14.
Pyriproxyfen is a chiral insecticide, and over 10 metabolites have been identified in the environment. In this work the separations of the enantiomers of pyriproxyfen and its six chiral metabolites were studied by high‐performance liquid chromatography (HPLC). Both normal phase and reverse phase were applied using the chiral columns Chiralpak IA, Chiralpak IB, Chiralpak IC, Chiralcel OD, Chiralcel OD‐RH, Chiralpak AY‐H, Chiralpak AD‐H, Chiracel OJ‐H, (R,R)‐Whelk‐O 1, and Lux Cellulose‐3. The effects of the chromatographic parameters such as mobile phase composition and temperature on the separations were investigated and the enantiomers were identified with an optical rotation detector. The enantiomers of these targets could obtain complete separations (resolution factor Rs > 1.5) on Chiralpak IA, Chiralpak IB, Chiralcel OD, Chiralpak AY‐H, or Chiracel OJ‐H under normal conditions. Chiralcel OJ‐H showed the best chiral separation results with n‐hexane as mobile phase and isopropanol (IPA) as modifier. The simultaneous enantiomeric separation of pyriproxyfen and four chiral metabolites was achieved on Chiralcel OJ‐H under optimized condition: n‐hexane/isopropanol = 80/20, 15°C, flow rate of 0.8 ml/min, and UV detection at 230 nm. The enantiomers of pyriproxyfen and the metabolites A , C , and D obtained complete separations on Chiralpak IA, Chiralpak IC, and Lux Cellulose‐3 under reverse phase using acetonitrile/water as the mobile phase. The retention factors (k) and selectivity factors (α) decreased with increasing temperature, and the separations were better under low temperature in most cases. The work is of significance for the investigation of the environmental behaviors of pyriproxyfen on an enantiomeric level. Chirality 28:245–252, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

15.
Abstract: The crude neurophysin containing extract from posterior lobes of porcine pituitaries was roughly purified by gel chromatography. 15 mg of the lyophilized neurophysin complex were completely separated by HPLC yielding in neurophysin I1 (3.6 mg), I2 (4.0 mg), II (4.6 mg) and III (1.9 mg). All of the neurophysins were homogenous by PAGE and SDS-electrophoresis, isoelectrofocussing, amino-acid composition and N- and C-terminal amino acid analysis. In conclusion, HPLC is a reliable and quick method for the preparation of pure neurophysins.  相似文献   

16.
本文介绍一种用高效波相色谱(HPLC)同时测定血清中24-脱氢胆固醇、7-烯胆甾烷醇、菜油甾醇、胆甾烷醇和β-谷甾醇的方法。血清加内标(6-氯豆甾醇)后用氢氧化钾醇溶液皂化,用正己烷提取其中的各种甾醇,将提出的甾醇衍生为苯氨基甲酸酯,用HPLC分离测定。本法样品处理简单,色谱分析时间短,批内和批间变异系数分别为2.2~3.8%和3.3~6.7%。本文也首次报告我国成年人血清非胆固醇甾醇水平,5种甾醇血清浓度的总和平均为1.54mg/dl,是胆固醇的0.86%。  相似文献   

17.
建立了一种高效液相色谱-库仑阵列电化学测定血浆中同型半胱氨酸的方法。采用3-2-羧乙基膦作为还原剂还原巯基间形成的二硫键,用0.1 mol.L-1HC lO4来沉淀血浆蛋白,离心取上清,进样分析。在0.40~50.00μmol.L-1范围内,线性关系良好。加标平均回收率是98.43%,RSD%是4.35%。该方法简单、快速、灵敏。  相似文献   

18.
Bis(4-chloro-2-ethylphenyl) phenylphosphonate was metabolically transformed into the cor-responding cyclic ester, i.e., 6-chloro-4-methyl-2-phenyl-4/f-1,3,2-benzodioxaphosphorin 2-oxide, in houseflies in vivo. In a p-unsubstituted analog, hydroxylation at the para-position of an ester linkage occurred preferably to alpha-hydroxylation with subsequent cyclization. The cyclization was diastereomerically selective, giving predominantly the cis ester. The biological activities of synthesized and related cyclic esters were similar to but weaker than saligenin cyclic phosphorus esters lacking a methyl group at the 4-position.  相似文献   

19.
Abstract

5-Fluorouracil (5-Fu) and 5-Fluorodeoxyuridine (FdUrd) are substances widely used in the chemotherapy of cancers. The exploration of the metabolic pathways, is of Beat interest when they are combined with drugs which are likely to alter their biological response. The method described consists in the detection with ion-pair microbore HPLC of minimum amounts, ranging from 100 to 500 pg.  相似文献   

20.
Minor nonpolar galactolipids were isolated from the total lipids of calf brain stem by column chromatography and were separated by preparative thin-layer chromatography into four groups. The material recovered from the bottom band of the thin-layer chromatography consisted of monogalactosyl diglyceride and its 1-0-alkyl isomer, alkylgalactolipid, present in a molar ratio of 11 :9. After perbenzoylation. they were separated by preparative thin-layer chromatography and characterized. The fatty acid compositions of these lipids were similar to each other and to those of the ester-linked fatty acids of cerebroside esters. The major alkyl group of alkylgalactolipid was palmityl, and the other, minor components were oleyl. myristyl, and stearyl ethers. Perbenzoylated derivatives of these lipids were further separated by reverse-phase high performance liquid chromatography. The chromatograms from these two lipids were similar; however, most of the peaks were still mixtures of homologs containing different fatty acids or an alkyl group.  相似文献   

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