Banana pulp extract mediated synthesis of Cu2O nanoparticles: An efficient heterogeneous catalyst for the ipso-hydroxylation of arylboronic acids

A green and facile novel procedure has been developed for the synthesis of Cu₂O nanoparticles within a very short reaction time using banana pulp extract as a reducing agent. The synthesized nanoparticles are well characterized by SEM (Scanning Electron Microscope), TEM (Transmission Electron Microscope) and powder XRD (X-ray Diffraction) methods. An environmental benign and highly efficient protocol for the ipso-hydroxylation of aryl and hetero arylboronic acids using bio-fabricated Cu₂O nanoparticles as a catalyst and aqueous H₂O₂ as an oxidant has also been developed. The main advantages of this protocol are the base free reaction condition, reusable and heterogeneous catalytic system, and short reaction time with excellent yields.     

Py-GC/MS分析烟用添加剂黄芩浸膏的热裂解产物

采用在线热裂解气相色谱-质谱法(Py-GC/MS)法研究了黄芩浸膏热裂解行为。在氦气氛围中,将黄芩浸膏分别在300、450、600、750和900℃下进行热裂解,并以GC/MS对其裂解产物进行定性和半定量分析,并用黄芩浸膏进行了卷烟加香试验。结果表明:①黄芩浸膏在这一系列裂解温度下检测到的挥发性热裂解产物分别为12种、19种、40种、55种和46种;②黄芩浸膏低温区(300℃～450℃)裂解后产生大量醛类、酮类、酯类和呋喃类物质,这些物质是构成卷烟香味的重要物质,能改善卷烟吸味、减轻刺激性;③在高温区(750℃～900℃)产生大量的芳香族化合物,如苯、甲苯、乙苯、萘等。该研究为香味物质在卷烟燃烧过程中的挥发性物质提供了例证。     

Estimating Aluminum leaching from Aluminum cook wares in different meat extracts and milk

A method of estimating Al leaching from Al cook ware in some meat extracts and liquid milk was investigated. In the present work four kinds of Al cook wares from four countries were chosen from the local market. Extracts of boiled meat (lamb, chicken, and fish) were used to make 10–50% (w/v) concentrations. In addition liquid fresh milk and long life milk were diluted to make 10–50% (v/v) concentrations. Weight loss (WL) method, atomic absorption, polarization method, and surface study were applied. The “estimated” Al intake per person from WL in 30% meat extract and milk range from 8.16 to 12.75 mg/h with fish extract having the highest leaching and chicken extract having the lowest leaching. Atomic absorption gave comparable results to that of WL. Comparing the present results with the Provisional Tolerance Weekly Intake of Al approved by the FDA/WHO shows that Al leaching from Al cook wares may add high doses of Al into the diet.     

On-line identification of 4″-isovalerylspiramycin I in the genetic engineered strain of S. spiramyceticus F21 by liquid chromatography with electrospray ionization tandem mass spectrometry,ultraviolet absorbance detection and nuclear magnetic resonance spectrometry

LC-hyphenated techniques were applied to the on-line identification of isovalerylspiramycin I (isp I), a spiramycin-like macrolide in the crude extract of fermentation broth from a genetically engineered strain of S. spiramyceticus F21. In the structural characterization of the large molecular secondary metabolite of isp I, LC–DAD-UV–ESI-MSⁿ analysis played a crucial role, and stop-flow LC–¹H NMR measurement, with bitespiramycin used as reference, was a valuable complement approach. This rational approach proved to be an efficient means for the rapid and accurate structural determination of known microbial secondary metabolites, by which targeted isolation of component(s) of interest can be subsequently performed for further biological and pharmacological studies in drug development.     

Simple quality assessment approach for herbal extracts using high performance liquid chromatography-UV based metabolomics platform

A lack of adequate or accepted research methodology has been a major obstacle to study herbal medicines. In this study, instead of the prevalent hyphenated chromatographies, common high performance liquid chromatography equipped with ultraviolet detector (HPLC-UV) and multivariate statistical analysis were utilized to assess the qualities of total flavones of sea buckthorn (TFS), an 85% ethanol extract of the sea buckthorn berries. Two complementary HPLC-UV methods were developed, validated and combined to comprehensively determine the ingredients in TFS. Principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) of the combined analytical data showed that the six batches of TFS could be well differentiated. Hierarchical cluster analysis (HCA) using Ward's minimum variance method of the PLS-DA loading matrix demonstrated the known ingredients (quercetin, kaempferol, isorhamnetin, oleanolic acid and ursolic acid) and three unknown ingredients in TFS significantly contributed to the quality differences. A PLS regression model indicated that the results of the present method correlated well with the content of total flavones, which is now the quality control approach of TFS. Results from this study indicated that the proposed method is reliable for the quality reassessment of some widely used herbal extracts.     

枫蓼肠胃康颗粒对非特异性和脾虚型溃疡性结肠炎的作用研究

为观察枫蓼肠胃康颗粒对非特异性和脾虚型溃疡性结肠炎豚鼠的血中E -玫瑰花环形成率 (Ea -RFC)、总E -玫瑰花环形成率 (Eτ -RFC)、溃疡个数、溃疡面积和水肿面积变化的影响 ,将杂毛豚鼠分成 6组 ,每组 10只 ,用二硝基氯苯Ⅰ、Ⅱ、Ⅲ液注入肠管法和番泻叶灌肠法 ,分别建立豚鼠慢性非特异性结肠炎和脾虚型溃疡性结肠炎动物模型 ,在 0、2 1d取血测定血中Ea -RFC及Eτ -RFC含量 ,脾虚动物于给药 7d处死 ,计出各组动物溃疡个数、溃疡面积和水肿面积 .结果表明 :各剂量给药组中的Ea -RFC、Eτ -RFC免疫指标较造模组升高 (P分别<0 .0 1和 <0 .0 5 ) ,受试药高、中剂量组溃疡个数、溃疡面积、水肿面积较造模组降低 (P分别 <0 .0 1和 <0 .0 5 ) .提示 :枫蓼肠胃康颗粒对豚鼠非特异性结肠炎和脾虚型溃疡性结肠炎有显著疗效 .     

飞龙掌血水提物的扩血管作用及原理初探

飞龙掌血的水提物飞龙一号(F01)给小鼠腹腔注射,其 LD_(50)=3.70g/kg。F01(80mg/kg)对麻醉 S.D.大鼠有明显降血压作用,伴有心率加快。该作用无快速耐受性,且不被 H_1及 H_2组胺受体、M 胆碱受体及β肾上腺素受体之阻断剂取消。对于离体 S.D.大鼠尾动脉螺旋条,F01(0.3至3mg/ml)可使由 KCl(60mmol/L)、NE(0.1μmol/L)或 AVP(0.01μmol/L)刺激而收缩的组织明显舒张。KCI(80mmol/L)增加血管平滑肌组织对钙的撮取,这可以通过测定组织中未被镧置换的低亲和力同位素~(45)Ca 的含量来确定。F01(0.06至4mg/ml)可显著降低这种钙摄取的增加。上述结果表明,F01具有直接扩张血管作用,此种作用与抑制钙内流有关。     

煤中砷,铅,铍,铬等元素的存在状态

煤是由有机物和无机物组成的混合物。无机物按其在煤中的浓度大小可分为三类:(1)常量元素,在煤中浓度大于0.5%,如Si,Al,Fe,Ca等。(2)次要元素,约占煤的0.02%—.5%,包括K,Mg,Na,Ti,有时还有P,Ba等。(3)微量元素,在煤中浓度<0.02%,这类元素目前已测出60种左右。60年代以来,基于能源需求的增加,国内外煤炭消耗量都很大,考虑到有害的微量元素对环境的污染,国外进行了大量的煤     

盐酸提取-液相色谱-原子荧光联用技术检测水产品中甲基汞等汞化合物

建立了HCl提取,高效液相色谱与原子荧光联用技术测定水产中无机汞、甲基汞、乙基汞形态的分析方法。对前处理方法和液相色谱的最佳参数进行优化,实验表明,3种汞化合物的线性范围为0~100μg/L,相关系数(r)均优于0.9990,检出限在0.3~0.6μg/L之间,汞化合物各形态的RSD均小于5%,加标回收率在78.8%~116.8%之间,标准物质(GBW10029),(GBW09101B)中汞形态的测定值均在标准值范围内,参加甲基汞FAPAS国际比对,测定结果的Z比分数为1.0,故本方法适用于水产品中汞化合物形态的分析测定。