铜藻中β-丙氨酸的分离及结构鉴定

非蛋白质氨基酸在抗癌、抗菌、抗结核、抗坏血病等方面有着重要的作用。本文主要对铜藻中的游离氨基酸进行检测分析和部分分离纯化及结构鉴定方面的研究,为更好的开发利用这些天然产物提供技术支持。采用离子交换树脂层析法分离铜藻粗提液中的游离氨基酸,收集3 mol/L的氨水洗脱液,用PITC-HPLC柱前衍生反相高效液相色谱法对其进行检测分析,结果显示粗提液中除含有多种组成蛋白质的氨基酸外还有3种未知组分,且含量较高的常见蛋白质氨基酸为丙氨酸、脯氨酸、缬氨酸。采用半制备高效液相色谱系统制备分离了其中一种未知组分的衍生物MWZ2,经真空冷冻干燥后为略黄固体粉末,结合核磁共振波谱、高分辨质谱、红外光谱数据,最终鉴定MWZ2去掉已知取代基团PITC后的成分为β-丙氨酸,分子式为C3H7NO2,分子量为89.09。     

Excitation energy transfer in intact cells and in the phycobiliprotein antennae of the chlorophyll d containing cyanobacterium Acaryochloris marina

The cyanobacterium Acaryochloris marina is unique because it mainly contains Chlorophyll d (Chl d) in the core complexes of PS I and PS II instead of the usually dominant Chl a. Furthermore, its light harvesting system has a structure also different from other cyanobacteria. It has both, a membrane-internal chlorophyll containing antenna and a membrane-external phycobiliprotein (PBP) complex. The first one binds Chl d and is structurally analogous to CP43. The latter one has a rod-like structure consisting of three phycocyanin (PC) homohexamers and one heterohexamer containing PC and allophycocyanin (APC). In this paper, we give an overview on the investigations of excitation energy transfer (EET) in this PBP-light-harvesting system and of charge separation in the photosystem II (PS II) reaction center of A. marina performed at the Technische Universität Berlin. Due to the unique structure of the PBP antenna in A. marina, this EET occurs on a much shorter overall time scale than in other cyanobacteria. We also briefly discuss the question of the pigment composition in the reaction center (RC) of PS II and the nature of the primary donor of the PS II RC.     

双叉犀金龟表皮蛋白TdCPR12611与TdCPR7854的表达纯化及特性分析

[目的]探析双叉犀金龟Trypoxylus dichotomus表皮蛋白的序列特征及生化性质.[方法]利用RT-PCR克隆双叉犀金龟表皮蛋白基因,利用生物信息学方法分析表皮蛋白的结构特征及系统发育;采用大肠杆菌Escherichia coli表达系统对双叉犀金龟表皮蛋白进行重组表达,并通过金属离子鳌合层析的方法对重组蛋...     

微滤膜分离提纯苦楝素的研究

通过对不同孔径和材质的微孔滤膜对苦楝提取液过滤分离比较,优选出孔径为0.45μm的聚醚砜微滤膜对苦楝提取液具有良好的过滤性能。确定的膜分离提纯苦楝素优化工艺条件是:在料液浓度为0.374 mg/mL,料液温度35℃,操作压力差为0.08 MPa,循环流量为0.15 L/h,pH=7.0,苦楝素的转移率为99.4%,除杂率为8.3%,通量为147.2 L/m2.h,苦楝素的纯度为由提取液的0.89%,提高到了8.79%。     

A Microfluidic Platform for Precision Small-volume Sample Processing and Its Use to Size Separate Biological Particles with an Acoustic Microdevice

A major advantage of microfluidic devices is the ability to manipulate small sample volumes, thus reducing reagent waste and preserving precious sample. However, to achieve robust sample manipulation it is necessary to address device integration with the macroscale environment. To realize repeatable, sensitive particle separation with microfluidic devices, this protocol presents a complete automated and integrated microfluidic platform that enables precise processing of 0.15–1.5 ml samples using microfluidic devices. Important aspects of this system include modular device layout and robust fixtures resulting in reliable and flexible world to chip connections, and fully-automated fluid handling which accomplishes closed-loop sample collection, system cleaning and priming steps to ensure repeatable operation. Different microfluidic devices can be used interchangeably with this architecture. Here we incorporate an acoustofluidic device, detail its characterization, performance optimization, and demonstrate its use for size-separation of biological samples. By using real-time feedback during separation experiments, sample collection is optimized to conserve and concentrate sample. Although requiring the integration of multiple pieces of equipment, advantages of this architecture include the ability to process unknown samples with no additional system optimization, ease of device replacement, and precise, robust sample processing.     

余甘原汁中多酚的大孔树脂提取分离及其抗氧化活性

为研究余甘子多酚的分离提取方法,本文以余甘原汁为原料,采用NKA-Ⅱ大孔吸附树脂,对上样量、洗脱剂、洗脱体积及洗脱速度等条件进行了考察,并对提取物的抗氧化活性进行了对比分析。通过试验确定了余甘原汁多酚的大孔树脂分离提取条件为:上样速度2BV/h,上样量0.8BV,洗脱剂为70%乙醇溶液,洗脱体积3BV,洗脱速度8BV/h,在此条件下NKA-Ⅱ大孔树脂对余甘原汁中多酚的吸附率可达到88.42%,洗脱率为90.93%,提取率为80.39%;对提取物的抗氧化活性分析显示,与分离前的余甘原汁干燥物相比,提取物的多酚和维生素C含量均提高了0.53倍,类超氧化物歧化酶活性(SODL)提高了1.4倍;铁离子还原能力(FRAP)明显高于分离前,对DPPH自由基、ABTS自由基及脂质氧化的半抑制浓度(IC50)均显著低于分离前的原汁干燥物,表明通过大孔吸附树脂分离,使余甘原汁中的多酚等抗氧化活性成分得到了有效的分离纯化。     

猪血粉分离氨基酸的研究

本文报道了从猪血粉中提取分离七种氨基酸(L—Phe、L—Tyr、L—His·HCl、L—lys·HAC、L—Arg·HCl、L—leu、L—Val)的小试工艺。通过合成一系列专用树脂(AAS—1、AAS—2、D083)对现行工艺脱酸、脱色及层析分离等过程作了较大改进,使猪血粉分离氨基酸的生产工艺全部树脂化,并使氨基酸收率大幅度提高。经周期性实验,每批投料130g猪血粉,七种氨基酸总回收率平均达34.9%。(占血粉量)。经自检产品质量基本符合注射用结晶氨基酸原料标准。     

微生物转谷氨酰胺酶的纯化方法和酶学性质研究

由Streptoverticillium mobaTaense发酵生产的转谷氨酰胺酶经过除茵体、超滤浓缩、乙醇沉淀、干燥后得到粗酶产品,其活力回收率约70％。又经Superdex-75凝胶过滤和Source 30S阳离子交换两步纯化后得到纯酶,最终酶活力收率约37％。酶最适温度为50℃,在40℃以下稳定性良好;最适pH为6．0,pH4．0～8．0时比较稳定。离子强度对酶影响很小。     

大孔吸附树脂柱层析分离淫羊藿甙的研究

本文通过考察八种大孔吸附树脂对淫羊藿甙的吸附分离性能,筛选出了AB-8树脂作为分离纯化淫羊藿甙的介质。对该树脂的吸附性能研究表明其对浸提物中的淫羊藿甙有良好的吸附选择性,静态饱和吸附容量和动态吸附容量分别为22．97和16．20mg／mL。通过柱层析实验确定了AB-8树脂分离淫羊藿甙的工艺,经一步层析可将淫羊藿甙的纯度从2．78％提高到27％,回收率达97．3％。     

金樱子多糖的分离纯化及组成分析

对金樱子多糖的分离纯化方法作了探讨,筛选出较佳的工艺条件,通过紫外分光光度法,红外光谱以及气相色谱法分别对金樱子多糖纯品LP2的纯度,分子构型,单糖组成进行了分析;并通过了DEAE-纤维素（氯型）柱层析得一葡聚糖。