三七素提取工艺及检测方法的优化

本研究以三七（Panax notoginseng）植株及其产品和近缘种为研究对象,采用L₉(3 ⁴)正交试验对三七素的提取工艺进行了优化,然后利用HPLC法检测三七素含量,并对各样品中的三七素含量进行了比较分析。结果表明：优化后的三七素提取条件为超纯水、料液比1∶20（g/mL）,提取1次（10 min）;三七素在三七花蕾中的含量最高,其次是根状茎和主根,但是三七茎叶中也有较高含量的三七素,说明三七花蕾和茎叶均可作为三七素的提取原料;在三七产品中三七花的三七素含量最高,达到3.33%,其次是剪口（根状茎）、筋条（侧根）和须根;但三七素的含量与三七个头大小（头数）并无明显的相关性;在三七近缘种姜状三七（P. zingiberensis）和野三七（P. vienamensis var. fuscidiscus）主根、珠子参（P. japonicus var. major）根状茎中的三七素含量显著低于三七主根三七素含量,也显著低于三七其他部位的三七素含量,说明三七是最佳的三七素来源植物。三七素的含量主要受到物种和部位的影响,与产品规格无关。本文所建立的三七素提取方法和HPLC检测方法,能够快速简便、稳定可靠测定样品中三七素含量;并可为三七素相关标准的建立奠定基础,为三七的综合利用开发提供依据。     

超高效液相色谱串联质谱法对水产品中硝基呋喃代谢物的测定

建立了使用Waters UPLC Xevo TQ超高效液相色谱串联质谱仪检测水产品中4种硝基呋喃代谢物的分析方法。匀浆后的样品在酸性环境下水解,并用2-硝基苯甲醛衍生16h,经磷酸氢二钾提取,LMS固相萃取小柱净化后,在三重四极杆多反应监测模式下进行测定。方法采用同位素内标法定量,四种代谢物的检出限(LOD)均低于0.25μg·kg-1,线性范围在0.5μg·L~(-1)到10μg·L~(-1)间,相关系数大于0.99。在0.5、1.0和5μg·kg-1浓度下分别进行添加回收试验(n=5),回收率在75.2%~123.3%之间,相对标准偏差(RSD)小于9.4%。     

仙草多糖提取工艺条件优化研究

采用水提法浸提仙草，以仙草多糖的提取率为指标，研究料液比、浸提温度、浸提时间及浸提次数4个因素对其提取率的影响，并从中挑取合适的因素水平进行正交试验及SPSS分析。结果表明：在这4个因素中，对提取率影响最大的因素是浸提温度，然后是浸提时间，再次是料液比，最后是浸提次数；在料液比1:60、温度100 ℃、浸提时间3 h的最优条件下，仙草多糖的提取率高达17.89 %，此时仙草多糖的含量为44.13 %。     

An improved method for extraction of sorghum polymeric protein complexes

A method for fractionating sorghum proteins using extraction solvents and techniques designed to obtain polymeric protein structures (especially disulfide linked) was developed. Extraction and separation conditions were optimized in terms of completeness of protein extraction, sample stability, and analytical resolution. After pre-extraction of albumins and globulins, a 3-step sequential procedure involving no reducing agents was applied to ground whole sorghum flour. The three fractions obtained represented proportionally different protein polymer contents and molecular weight distribution as evidenced by comparative size exclusion chromatography. Protein composition also varied among the extracts with differences in kafirin composition and non-kafirin proteins detected in the fractions by RP-HPLC and SDS-PAGE analysis. The ability to quantify and further characterize sorghum polymeric protein complexes will be useful for additional studies linking protein structures with functionality and digestibility and variations for these properties within diverse sorghum germplasm.     

裂褶菌多糖的研究进展

裂褶菌多糖(Schizophyllan)是裂褶菌(Schizophyllum commune)的主要活性成分之一.综述了裂褶菌多糖结构、提取纯化工艺和生理活性功能等方面的研究进展.     

地稔凝集素的提取及凝血活性的研究

为研究和利用地稔的促凝血活性物质,以地稔为试材,提取地稔凝集素,研究pH、温度和糖等理化因素对凝血活性的影响。结果表明:经硫酸铵沉淀及透析提取的地稔凝集素具有红细胞凝集活性;碱性条件下,抑制作用明显,而酸性条件有较强促进作用;温度对凝集素凝血活性影响很小;半乳糖有明显促进作用。     

Importance of Noncrystalline Hydroxide Phases in Sequential Extractions to Fractionate Antimony in Acid Soils

Abstract

Sequential extraction techniques have been used to make inferences about speciation of phosphorus (P) and to a lesser extent arsenic (As) in soils. However, sequential extraction studies on the less‐abundant group V element, antimony (Sb), are limited. In this work, a widely used P sequential extraction scheme was modified and used to extract P, As, and Sb from two acidic soils from the Macleay River floodplain, NSW, that were enriched with Sb (26.9 and 23.0 mg kg^?1). An ammonium oxalate–oxalic acid step was included in the extraction sequence to dissolve the noncrystalline iron (Fe) and aluminium (Al) hydroxide phase. It extracted 30 to 47% of Sb, indicating the importance of this fraction, which may be mobilized in the floodplain by acid sulfate soil processes and periodic waterlogging. The original method overestimated P, As, and Sb in the residual fraction (30–71%). Relative efficiency values of extracts for P, As, and Sb were compared, and inferences about phase distributions were made. The results suggest some potential in using extractions to assess bioavailability of Sb in soil.     

生物酶法提取中草药活性成分研究进展

对酶提方法的原理、酶类选择依据、酶提工艺,以及酶提法应用现状进行了综述,旨在为同类研究提供技术参考。中草药具有广泛的应用前景和开发潜力,为提高中药疗效,方便临床用药,生产中常需要对中草药进行提取,然而传统的提取方法较为繁杂。随着科技进步,一些现代中药提取方法不断涌现。酶提方法是一种应用酶工程技术提取中药的现代中药提取方法,该方法具有高效、无毒、反应条件温和等优点,是一种发展潜力较大的中药提取方法。     

分散固相萃取结合UPLC-Orbitrap MS联用测定鸡蛋中五氯苯酚残留量

建立了超高效液相色谱-静电轨道阱质谱联用测定禽蛋中五氯苯酚残留量的分析方法。取均质后的禽蛋样品经乙腈溶液提取,加入无水硫酸镁和氯化钠进行脱水和盐析,高速离心分层后,取适量乙腈层溶液经0.1%(V∶V)甲酸稀释后,用酸性氧化铝粉末进行样品净化并以10000 r/min离心取上清液,过0.22μm滤膜后上机测定。使用反相色谱柱进行分离,流动相为乙腈:0.1%甲酸=75∶25,采用等度程序进行洗脱,静电轨道阱质谱进行定性定量分析。结果表明,五氯苯酚在0.5~100μg/kg范围内线性关系良好(r>0.995),方法的最低检出限为0.2μg/kg,最低定量限为0.5μg/kg,添加回收率在74.43%~96.85%之间,批内批间变异系数CV%<10%。该方法具有较好的准确度与精密度,适用于禽蛋中五氯苯酚残留量的测定。     

酸与碱处理对海带多糖提取及其抗氧化活性的影响

本试验采用柠檬酸提取法和碱提取法从海带中提取多糖组分,以总抗氧化能力和羟自由基（·OH）为衡量抗氧化活性指标,比较这两种提取方法得到海带粗多糖产率和抗氧化活性。试验结果表明：柠檬酸提取法和碱提取法的提取率分别为15.92%和6.05%,所提取的海带粗多糖具有良好的抗氧化活性,且柠檬酸提取法抗氧化活性更高。 [关键词] 柠檬酸提取法|碱提取法|海带多糖|抗氧化活性