RP-HPLC法测定不同产地红枣中甜菜碱的含量

目的:通过对影响甜菜碱提取和测定的符种因素进行了研究,建立了一种准确、快速的测定不同产地红枣中甜菜碱的方法.方法:样品采用超声波甲醇提取的方法,得到的样品采用反相C18柱进行分离,色谱条件为:流动相为50mmol/L pH 4.5的KH2PO4溶液;192nm波长测定,流速0.7ml/min.结果:总分析时间:4.5min.甜菜碱平均保留时间2.698min.甜菜碱在5.0～25.0mg/ml线性关系良好(r2=0.9911),平均回收率为96.87%.结论:该法测定红枣中甜菜碱含量简便、快速、准确,重现性好.     

RP-HPLC法测定长期盐胁迫下盐爪爪和盐穗木中的甜菜碱

通过对影响甜菜碱提取和测定的各种因素进行研究,建立了一种准确、快速的测定长期盐胁迫下盐爪爪和盐穗木中甜菜碱的HPLC方法。样品采用超声波甲醇提取,并依次通过强阴阳离子交换树脂(Dowex 50×8和Dowex 50×2)进行纯化,得到的样品采用反相C18柱进行分离,色谱条件:流动相为50 mmol/L、pH 4.5的KH2PO4溶液;波长200 nm下紫外测定,流速0.7 mL/min;此方法的检出限为0.02μg/mL,平均回收率为97.2%。通过对0~500 mmol/L NaCl胁迫下的盐爪爪和盐穗木中甜菜碱进行测定,甜菜碱的含量均呈现先增加后减少的趋势,盐爪爪在NaCl浓度为200 mmol/L时达到最大,而盐穗木在NaCl浓度为300 mmol/L时达到最大。     

超高效液相色谱法测定麻黄中l-麻黄碱和d-伪麻黄碱的含量

目的:建立超高效液相色谱法(UPLC)测定麻黄中l-麻黄碱和d-伪麻黄碱含量的方法,为麻黄药材质量评价提供依据。方法:UPLC测定麻黄碱色谱柱为Waters Acquity BEH-C_(18)(2.1 mm×50 mm, 1.7μm);检测波长:214 nm;流动相为0.15%氨水水溶液(A)和乙腈(B),梯度洗脱(0.0～4.0 min,5%B→55%B;4.0～4.1 min,55%B→95%B;4.1～4.7 min,95%B;4.7～4.8 min,95%B→5%B;4.8～5.0 min,5%B),流速:0.7mL/min;柱温:25℃。结果:l-麻黄碱和d-伪麻黄碱分别在12.50～500.00μg/mL和10.50～420.00μg/mL范围内具有良好的线性关系,相关系数均为0.9999,UPLC方法测定l-麻黄碱和d-伪麻黄碱的回收率分别为101.99%和98.68%。应用UPLC方法测定麻黄药材中的l-麻黄碱和d-伪麻黄碱的含量,麻黄药材两者含量分别为0.80%和0.18%。结论:与常规HPLC测定l-麻黄碱和d-伪麻黄碱含量方法比较,本文所用方法测定结果更加准确、全面、且重复性好,能够快速测定麻黄药材中的l-麻黄碱和d-伪麻黄碱的实际含量;并且对麻黄碱及相关物质的测定有一定的指导意义。     

甜菜碱合成代谢基因工程的研究进展

甜菜碱（Betaine）是生物体内氨基酸代谢的中间产物［1］,可作为甲基供体,参与“一碳单位”的活化的甲基循环［2］。许多生物,特别是依赖环境条件而代谢类型多样化的植物、细菌和水生低等生物,在干旱、盐渍、深冻等低水势的逆境中,为了维持细胞的渗透势,合成和积累有机小分子,如脯氨酸［3］、甜菜碱［4］等氨基酸类,岩藻糖［5］、甘露醇［6］等单糖、双糖、三糖及糖醇类物质。LeRudalier［1］等（1984）法国和美国科学家合作,用150种代谢中间产物作体外渗透胁迫实验,发现只有甘氨酸甜菜碱和脯氨酸甜菜碱能有效地促进细胞生长,…     

植物磷酸乙醇胺N-甲基转移酶的研究进展

甘氨酸甜菜碱是一种渗透调节物质,能够维持高盐浓度下细胞的渗透平衡和膜的有序性,并有效地稳定酶的结构;胆碱是甘氨酸甜菜碱生物合成的必要前体物质,而磷酸乙醇胺甲基转移酶（phosphoethanolamineN-methyltransferase,PEAMT）作为甲基转移酶,是催化磷酸乙醇胺三次甲基化生成胆碱的限速酶。近年来研究表明磷酸乙醇胺甲基转移酶不仅在植物生长发育过程发挥作用,而且通过参与渗调物质甜菜碱以及胁迫相关第二信使磷脂酸的合成从而使植物对盐胁迫产生应答反应。本文就植物磷酸乙醇胺甲基转移酶的反应作用机理、生物学功能及表达调控机制进行了归纳总结。     

高效液相色谱-质谱联用法分析微生物降解植物甾醇为雄甾烯酮

采用高效液相色谱-质谱联用法(HPLC/MS)分析测定植物甾醇侧链降解过程中产物雄甾-1,4-二烯-3,17-二酮(ADD)及雄甾4-烯-3,17-二酮(AD).其中液相色谱的条件为色谱柱Alltima C18ODS-2(5μm,250 mm×4.6 mm);流动相甲醇:水(V/V=7:3);流速1 mL/min;柱温室温;紫外检测器的检测波长244 nm.质谱为ZMD Micromass电喷雾质谱仪.结果测得ADD与AD标准样品的保留时间分别为9.70 min与11.13 min,发酵样品的HPLC与MS图谱与ADD与AD标准样品的图谱一致.采用高效液相色谱法定量ADD与AD的线性范围在0.01 mg/mL～0.09 mg/mL,产物回收率分别为102.6%与105.90%,日内精密度分别为3.02%与3.08%,日间RSD分别为3.50%与3.24%.该方法灵敏度高、选择性好、操作简便、定量准确,适用植物甾醇微生物侧链降解过程中产物的分析及产品质量控制.     

HPLC-DAD和UPLC-MS/MS对蔓花生中二苯乙烯类化合物的研究

采用HPLC-DAD和UPLC-MS/MS对蔓花生中白藜芦醇、白藜芦醇苷和二苯乙烯苷三种二苯乙烯类化合物进行鉴定,建立HPLC-DAD同时测定三种化合物含量的方法。HPLC-DAD分析采用依利特ODS1色谱柱,柱温40℃,流动相A为甲醇,B为1%乙酸水溶液,流速1.0 mL/min。UPLC-MS/MS采用ACQUITY UPLC BEH C18色谱柱,流动相A为乙腈,B为水,电喷雾离子源,负离子检测,数据采集方式为多反应监测模式(MRM)。结果表明:蔓花生根、茎和叶中白藜芦醇含量分别为66.28、90.83和81.56μg/g,白藜芦醇苷含量分别为123.78,302.77和236.53μg/g,根和茎中二苯乙烯苷含量分别为673.60和764.65μg/g,叶中未检测到二苯乙烯苷。     

大黄鱼共生菌Bacillus coagulans LL1103的代谢产物研究

[目的]研究大黄鱼共生菌Bacillus coagulans LL1103的次生代谢产物及其抑菌活性。[方法]利用色谱层析技术对B.coagulans LL1103发酵液乙酸乙酯和正丁醇提取物进行分离纯化;运用波谱技术鉴定化合物的结构;采用微量肉汤稀释法对化合物进行抗菌活性测定。[结果]从大黄鱼内生菌B.coagulans LL1103发酵液中分离并鉴定9个环二肽类化合物,分别为:(1)环(4-羟基-脯氨酸-亮氨酸)、(2)环(异亮氨酸-丙氨酸)、(3)环(脯氨酸-缬氨酸)、(4)环(脯氨酸-苯丙氨酸)、(5)环(脯氨酸-亮氨酸)、(6)环(甘氨酸-丙氨酸)、(7)环(脯氨酸-甘氨酸)、(8)环(脯氨酸-丙氨酸)和(9)环(络氨酸-甘氨酸)。活性评价显示化合物3、7和9对大肠埃希菌(Escherichia coli)具有较强抑制作用,最低抑菌浓度(minimal inhibitory concentration,MIC)分别为8.0、4.0和16.0μg/mL。[结论]从大黄鱼共生菌B.coagulans LL1103的发酵液中分离得到3个对大肠埃希菌(E.coli)具有较好抑制活性的化合物。     

盐胁迫下小麦甜菜碱和脯氨酸含量变化

运用高效液相色谱-质谱(HPLC-MS)联用技术分析了耐盐性强、中、弱3个小麦品种SW12、宁春4号和中国春苗期5个NaCl浓度胁迫下甜菜碱和脯氨酸含量的变化.方差分析表明盐胁迫下3个小麦品种之间甜菜碱的含量差异达到极显著水平(P＜0.01),SW12的含量最高,宁春4号次之,中国春最低,与小麦耐盐性表现相一致;脯氨酸在叶片中的含量差异不显著,在根中宁春4号和中国春的含量有显著差异(P＜0.05).结果表明:小麦叶和根中甘氨酸甜菜碱含量与小麦盐胁迫呈正相关,是小麦体内抵御盐胁迫的渗透调节物质之一,可作为小麦耐盐性鉴定指标.     

RP-HPLC法同时测定十种五加属植物叶中三萜Chiisanoside和Chiisaogenin

建立反相高效液相色谱法(RP-HPLC)测定chiisanoside和chiisanogenin的定量分析方法,利用最优色谱条件对十种中韩五加属植物叶中的三萜chiisanoside和chiisanogenin进行定量分析.研究结果表明,最佳色谱条件为:ODS-C18色谱柱(250mm×4.6mm,5μm);流动相:乙腈-水(55:45);检测波长:205 nm;柱温:40℃;流速:1.0 mL/min.Chiisanoside和chiisanogenin线性范围和回归方程分别为16.5～ 181.5 μg/mL,Y=5498356X-9738(r=0.9995)和4.88～78.0 μg/mL,Y=5753131X-8289 (r=0.9979),加样回收率分别为98.87％(标准偏差为1.14％)和98.83％(标准偏差为0.72％).     

New amino-dithiaphospholanes and phosphoramidodithioites and their rhodium and iridium complexes

New sulfur derivatives of phosphoramidite ligands were synthesized and the impact of the sulfur unit on the spectroscopic properties of their rhodium and iridium complexes was investigated. The new ligands Bn₂NPSCH₂CH₂S^a(P-S^a) (Bn = benzyl, 4), Bn₂NPSCHCHS^a(CH₂)₃C^aH₂(P-S^a)(C^a-S^a) (6) and Bn₂NP(4-XC₆H₄OMe)₂ (X = S, 7a; X = O, 7b) were converted to the rhodium and iridium complexes trans-[Rh(CO)Cl(L)₂] (L = 4, 6, 7), [RhCl(COD)(L)] (L = 4, 6, 7), [IrCl(COD)(7a)] and [IrCl₂Cp∗(6)]. For comparison, some phosphoramidite complexes of these formulations also were synthesized. The new metal complexes were spectroscopically analyzed. For the carbonyl complexes, the ν_CO IR stretching frequencies were lower than for the corresponding phosphite and phosphoramidite ligands. The ¹J_PRh coupling constants for the rhodium complexes with the new ligands were also smaller than for the respective phosphoramidite and phosphite complexes. Finally, the ¹J_PSe coupling constants of the selenides of the new ligands were lower than those of the phosphoramidite ligands but higher than for PPh₃. The spectroscopic data reveal that the new thio ligands 4, 6 and 7a are more electron donating than phosphites and phosphoramidites but less electron donating than PPh₃.     

Astrocytes and Synaptosomes Transport and Metabolize Lactate and Acetate Differently

Astrocytes transport the monocarboxylate acetate, but synaptosomes do not. The reason for this is unknown, because both preparations express monocarboxylate transporters (MCT). The transport and metabolism of lactate, another monocarboxylate, was examined in these two preparations, and the results were compared to those for acetate. Lactate transport is more rapid in astrocytes than in synaptosomes, but of lower affinity (Kms of 17 and 4 mM, respectively). Lactate (0.2 mM) is metabolized to CO2 more rapidly in synaptosomes than in astrocytes (rates of 0.37 and 0.07 nmol x mg protein(-1) x min(-1), respectively). The reason for this is unclear, but cellular differences in lactate dehydrogenase isotype expression may be involved. Acetate is metabolized to CO2 more rapidly in astrocytes than in synaptosomes (rates of 0.43 and 0.02 nmol x mg protein(-1) x min(-1), respectively). This is likely due to cellular differences in the expression of monocarboxylate transporter subtypes.     

白蚁与动物及微生物的共生类型及其机制

综述了白蚁螱客的主要种类、共生关系及相关机制的研究进展。白蚁螱客中,已报道的动物种类达170种。在与动物的共生关系中存在偏利共生（宾主共栖和异种共栖）、互利共生和无关共生三种;在与微生物的共生关系中,存在与内生菌（原生动物、细菌、真菌和放线菌）和外生菌（蚁巢伞菌等）间的互利关系。指出了白蚁与螱客研究中存在的问题,给出了解决方案,并提出了今后可能的研究热点或方向,为白蚁的综合利用（如纤维素酶）及今后研究物种间的协同进化提供了基础资料。     

Rapporteur report: Basics and technology and metrology and standards

The first and second sessions of the Workshop focussed on the basics of ultrasound and infrasound, their applications in both industry and medicine, and metrology and protection standards for ultrasound applications.     

Relative and combined effects of ethanol and protein deficiency on strontium and barium bone content and fecal and urinary excretion

To elucidate accumulation of minerals in human iliac arteries with aging, the content of minerals was analyzed by inductively coupled plasma atomic emission spectrometry. Bilateral common, internal, and external iliac arteries of 16 men and 8 women, ranging ages from 65 to 93 yr, were examined. It was found that an extremely high accumulation of calcium and phosphorus occurred in the common iliac artery at old age, being higher than that of the internal and external iliac arteries. It should be noted that the accumulation of calcium and phosphorus is the highest in the common iliac artery among the human arteries examined to date. Regarding sexual differences, the content of calcium and phosphorus in the common and internal iliac arteries was higher in women than in men, whereas their content in the external iliac artery was lower in women than in men.     

Cytoskeleton and mitochondrial morphology and function

It has been well established that the cytoskeleton is an essential modulator of cell morphology and motility, intracytoplasmic transport and mitosis, however cytoskeletal linkage to the organelles has not been unequivocally demonstrated. Indeed, cytoskeleton appears to be essential in determining and modulating gene phenotype as a function of cellular environment. According to recent studies, the organization of the cytoskeleton network together with associated protein(s) could be essential in regulating mitochondrial function and particularly the permeability of the mitochondrial outer membrane to ADP. The aim of this chapter is to summarize the main properties of the cytoskeletal environment of mitochondria and the possible role(s) of this network in mitochondrial function in myocytes.     

Cross-reactivity between storage and dust mites and between mites and shrimp

Many patients have sensitivities to multiple species of storage and house dust mites. It is not clear if this is because patients have multiple sensitivities to species-specific mite allergens or if these mites share many cross-reacting allergens. Our objective was to further define the cross-allergenicity between several species of storage and house dust mites using crossed-immunoelectrophoresis (CIE), crossed-radioimmunoelectrophoresis (CRIE), immunoblotting, and ELISA. CIE and CRIE reactions revealed that storage mites shared two cross-antigenic molecules and one of these bound IgE in a serum pool from mite allergic patients. Antibody in anti-sera built to each species of mite recognized many SDS–PAGE resolved proteins of other mite species and this suggested the potential for other cross-reactive allergens. Among patient sera, IgE bound to many different proteins but few had IgE that bound to a protein with common molecular weights across the mite species and this suggested mostly species-specific allergens. Antiserum built to each mite species precipitated one protein in shrimp extracts that bound anti-Der p 10 (tropomyosin) and IgE in the serum pool. Anti-Der p 10 showed strong binding to shrimp tropomyosin but very little to any of the mite proteins. ELISA showed the mite extracts contained very little tropomyosin. The storage and dust mites investigated contain mostly species-specific allergens and very small amounts of the pan-allergen tropomyosin compared to shrimp and snail.     

人血管能抑素基因的克隆、表达及其表达产物的纯化和生物活性测定

以人胎盘脐带组织为材料,提取组织总RNA,用netRTPCR方法合成人血管能抑素cDNA基因,将该cDNA克隆进pSP72载体获得重组质粒pSP72C, DNA序列分析结果与预期序列一致。用BamHⅠ和NdeⅠ双酶切,切下pSP72C上的血管能抑素cDNA,插入pET3c载体的相应位点获得重组表达质粒pETC, 转化E. coli BL21(DE3), SDSPAGE分析显示：在IPTG诱导下,血管能抑素基因获得了高效表达,表达量约占菌体总蛋白的 27.9 %,主要以包涵体形式存在。包涵体经过洗涤、裂解、蛋白复性以及Sephadex G75凝胶过滤层析等步骤后,获得了纯度达91.4 %的人血管能抑素。CAM实验证明10 μg纯化蛋白就能显著抑制鸡胚新生血管生成。     

Oxidation and nitration of ribonuclease and lysozyme by peroxynitrite and myeloperoxidase

In spite of the many studies on protein modifications by reactive species, knowledge about the products resulting from the oxidation of protein-aromatic residues, including protein-derived radicals and their stable products, remains limited. Here, we compared the oxidative modifications promoted by peroxynitrite and myeloperoxidase/hydrogen peroxide/nitrite in two model proteins, ribonuclease (6Tyr) and lysozyme (3Tyr/6Trp). The formation of protein-derived radicals and products was higher at pH 5.4 and 7.4 for myeloperoxidase and peroxynitrite, respectively. The main product was 3-nitro-Tyr for both proteins and oxidants. Lysozyme rendered similar yields of nitro-Trp, particularly when oxidized by peroxynitrite. Hydroxylated and dimerized products of Trp and Tyr were also produced, but in lower yields. Localization of the main modified residues indicates that peroxynitrite decomposes to radicals within the proteins behaving less specifically than myeloperoxidase. Nitrogen dioxide is emphasized as an important protein modifier.