考马斯亮蓝法测定青霉素发酵液中可溶性蛋白质含量

以青霉素发酵液为原料,利用蛋白质与考马斯亮蓝显色原理,测定发酵液中蛋白质含量,并对检测方法进行验证,检测波长为595 nm。蛋白质含量在0～30μg/mL时与吸光度有良好的线性关系,测定所需标准曲线方程为y=0.003 9 x＋0.048 8。采用考马斯亮蓝法测定青霉素发酵液中蛋白含量具有速度快、精确度高、重现性好等特点。     

HPLC-MS法测定黄芪中黄酮类成分的含量

采用Acclaim 120 C_(18)色谱柱,以乙腈-0.3%甲酸溶液为流动相,流速为1.0 mL/min,以离子监测(SIM)为扫描模式测定黄芪药材中黄酮类成分含量。研究发现毛蕊异黄酮苷、芒柄花苷、毛蕊异黄酮、芒柄花素检测的线性范围分别为0.0084～2.217 mg/mL(r=0.9991)、0.0049～1.287 mg/mL(r=0.9995)、0.0027～0.6847 mg/mL(r=0.9994)、0.00194～0.482 mg/mL(r=0.9998);精密度试验、稳定性试验、重复性试验RSD均2.0%;平均加样回收率(n=6)分别为100.31%、99.85%、100.45%、100.72%。该方法简便,可靠,准确,可用于黄芪药材质量控制。     

高效液相色谱法测定发酵液中丙酮酸的含量

建立了高效液相色谱法测定发酵液中丙酮酸含量方法。采用氨基柱进行液相色谱检测,检测波长210nm,柱温30℃,流动相采用乙腈／磷酸二氢钾。对检测方法的检出限、定量限、线性、精密度、稳定性进行考察。该方法线性方程为：y=0．3246x＋0．051,在5-200μg／mL内,线性关系良好（r=0．9999）。该方法适合于发酵液中丙酮酸含量测定。     

气相串联质谱法测定薄荷香精中二氢香豆素

建立了快速测定薄荷香精中二氢香豆素的气相色谱-串联质谱(gas chromatography-triple quadrupole tandem mass spectrometry,GC-MS/MS)方法。样品经涡旋提取、高速离心后,取上清液注入GC-MS/MS测定,结果表明:该方法在0. 0001 mg/mL到0. 0100 mg/mL的质量浓度范围呈良好的线性关系,相关系数为0. 9995;空白基质样品在3个加标水平0. 001、0. 002、0. 004 mg/mL的回收率为105%～117%,相对标准偏差(n=6)为3. 6%～4. 1%,方法检出限为0. 5 mg/kg,定量限为1. 5 mg/kg。该方法具有低毒、灵敏、高效、准确的特点,适用于薄荷香精中二氢香豆素的测定。     

反相高效液相色谱法测定发酵液中子囊霉素含量

建立用反相高效液相色谱法(RP-HPLC)测定发酵液中子囊霉素含量方法。采用Kromasil C18(250 mm×4.6 mm,5μm)色谱柱,以V(乙腈)∶V(水)=70∶30为流动相,柱温40℃,流速1.0 mL/min,检测波长210 nm,进样量20μL。子囊霉素标准品质量浓度在0.02~2.0 mg/mL范围内线性关系良好,线性回归方程为ρ=0.003 88A-0.001 41,r=0.999 97。平均回收率为99.79%(n=9),相对标准偏差(RSD)为0.45%。     

马兰叶总黄酮的提取及其含量的测定

优化了马兰叶总黄酮的超声提取工艺.结果表明,最佳的提取工艺是：乙醇体积分数为80％,提取温度50℃,料液比1/50（g/mL）,提取时间50 min,总黄酮的提取率为7.01％.以氯化铝为显色剂、芦丁为标准品,用紫外分光光度法测定黄酮含量.检测波长为418 nm,芦丁浓度在0.004～0.100 mg/mL,有良好的线性关系（R2=0.998 6）,平均加样回收率为97.4％（RSD=0.96％,n=5）,该方法简单、重复性好、结果可靠,适于马兰叶总黄酮的含量测定.     

高效液相色谱法测定依捷邦A产品中羟乙基磺酸钠的含量

采用高效液相色谱分离,蒸发光散射检测器检测的方法测定原料依捷邦A中羟乙基磺酸钠含量.色谱条件为:Lichrospher-C18(250 mm×4.6 mm,5μm)色谱柱,流动相为甲醇,流速0.4 mL/min.蒸发光散射检测器,检测器的喷雾室级别60%(36℃)、漂移管温度50℃、氮气压力172.369 Pa.结果表明,在此条件下羟乙基磺酸钠在0.004 mg/mL～1.0 mg/mL与相应的峰面积具有良好的线性关系(R2=0.999 6),回收率为94.3%～103.7%,方法精密度RSD为1.80%,并用离子色谱法验证该检测结果.     

高效液相色谱法测定沙棘油乳剂精华素中维生素E的含量

采用反相高效液相色谱法对沙棘油乳剂精华素中维生素E进行含量测定。色谱柱为ODS柱 ( 15 0mm×4.6mm) ,流动相为甲醇 ,检测波长为 2 92nm ,流速为 1 0mL/min。线性范围为 0 3mg/mL～ 0 8mg/mL ,r =0 9999(n =6 ) ;平均加样回收率为 97 76 % ,RSD =2 34%。方法灵敏可靠 ,可以用来控制沙棘油乳剂精华素产品质量     

HPLC-ELSD法同时测定甲壳素降解发酵液中果糖和葡萄糖

建立HPLC-ELSD同时测定甲壳素降解发酵液中果糖和葡萄糖含量的分析方法。样品离心分离过滤膜。Prevail Carbohydrate ES柱(4.6 mm×250 mm,5μm),流动相乙腈-水(83∶17),流速0.8 mL·min~(-1)。ELSD漂移管温度:90℃;载气流量:1.5 L/min;进量样10μL,柱温30℃的条件测定。果糖和葡萄糖含量的线性范围分别为0.1151.152 mg/mL(r0.9995)、0.1511.51mg/mL,(r0.9998)。13个批次的发酵液果糖含量为32.18135.68 mg/mL,葡萄糖含量为31.66119.84 mg/mL。方法简便、准确、专属性强,可用于甲壳素降解发酵液中果糖和葡萄糖含量的质量控制。     

GPC-ELSD测定发酵液中消泡剂丙三醇聚氧丙烯聚氧乙烯醚

建立了凝胶渗透色谱分离,蒸发光散射检测器检测测定发酵液中消泡剂丙三醇聚氧丙烯聚氧乙烯醚含量测定方法。前处理采用甲苯萃取发酵液中消泡剂,0.45μm膜过滤。取适量滤液进行液相分析。选用Shodex GPC KF-802色谱柱(300 mm×8.0 mm i.d),四氢呋喃为流动相,流速1.0 mL/min,蒸发光散射检测。该方法具有很好的重现性和线性关系,在0.1～0.8 mg.mL-1浓度范围内,相关系数均达到0.995以上,加标回收率为96.0%～102.5%,相对标准偏差小于1.5%。该方法简便、准确、灵敏度高。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料，介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比，介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序，对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。     

Inorganic/organic nanocomposite coatings: The next step in coating performance

Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.