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1.
The effects of ultraviolet (UV) radiation, particularly UV-B on algae, have become an important issue as human-caused depletion of the protecting ozone layer has been reported. In this study, the effects of different short-term UV-B radiation on the growth, physiology, and metabolism of Porphyra haitanensis were examined. The growth of P. haitanensis decreased, and the bleaching phenomenon occurred in the thalli. The contents of total amino acids, soluble sugar, total protein, and mycosporine-like amino acids (MAAs) increased under different UV-B radiation intensities. The metabolic profiles of P. haitanensis differed between the control and UV-B radiation-treated groups. Most of the differential metabolites in P. haitanensis were significantly upregulated under UV-B exposure. Short-term enhanced UV-B irradiation significantly affected amino acid metabolism, carbohydrate metabolism, glutathione metabolism, and phenylpropane biosynthesis. The contents of phenylalanine, tyrosine, threonine, and serine were increased, suggesting that amino acid metabolism can promote the synthesis of UV-absorbing substances (such as phenols and MAAs) by providing precursor substances. The contents of sucrose, D-glucose-6-phosphate, and beta-D-fructose-6-phosphate were increased, suggesting that carbohydrate metabolism contributes to maintain energy supply for metabolic activity in response to UV-B exposure. Meanwhile, dehydroascorbic acid (DHA) was also significantly upregulated, denoting effective activation of the antioxidant system. To some extent, these results provide metabolic insights into the adaptive response mechanism of P. haitanensis to short-term enhanced UV-B radiation.  相似文献   

2.
胸腺五肽(TP5)是一种很有发展前景的药物,具有胸腺素的全部生理功能。固相合成法是胸腺五肽生产的主流技术,目前,对固相合成的五肽一般采用反相色谱技术纯化,但效率低、成本高,仅限于小规模制备。实验采用离子交换法纯化,并进行了方案优化,发现在pH4 4醋酸盐缓冲液平衡、盐梯度洗脱条件下纯化TP5,一步分离纯度可达98 23%。该法可以满足大规模制备的要求,且成本很低。  相似文献   

3.
本研究旨在制备两种琉璃苣叶水溶性多糖,进一步探究其结构特征,并评价其降血糖、抗癌和免疫活性。采用纤维素酶辅助提取(BLP-1)和微波辅助提取法(BLP-2)制备琉璃苣叶水溶性多糖,并比较了BLP-1和BLP-2的理化性质,通过分析α-葡萄糖苷酶和α-淀粉酶的抑制效果来评价BLP-1和BLP-2的降血糖活性,通过检测HepG2、MX-1和A549细胞的抑制率来评价抗癌活性,通过检测RAW246.7的免疫因子分泌来评价免疫活性。结果表明,BLP-1和BLP-2具有不同的多糖和蛋白质含量。BLP-1和BLP-2由阿拉伯糖(Ara)、半乳糖(Gal)、葡萄糖(Glc)、木糖(Xyl)组成,但摩尔比组成不同,其分子量分别为20.1和22.6KDa。热重分析(TGA)表明BLP-2比BLP-1具有更稳定的结构。这两种多糖具有抑制α-葡萄糖苷酶和α-淀粉酶活性、抑制HepG-2、A549和MX-1癌细胞增殖以及激活巨噬细胞RAW 264.7细胞分泌免疫细胞因子以介导细胞免疫反应的潜力。两种多糖可作为新功能食品和医药产品中的生物活性成分,为进一步研究两种多糖的构效关系提供了理论依据。  相似文献   

4.
对甘肃临泽出产的凹凸棒矿石进行了纯化、分离实验,确定了高速剪切结合超声波分散的提纯方案,提纯率可达99%以上,且矿浆的悬浮性能大幅提高,并对原矿和提纯矿进行了XRD、FT-IR、SEM、TEM等分析,结果表明经过适当的方法纯化,甘肃凹凸棒矿石的纯度和性能大幅度提高,应用领域和应用价值提高,具备工业化生产的可行性.  相似文献   

5.
为了得到果糖单酯纯品,需要将果糖单酯与未反应的糖及脂肪酸、催化剂、以及其他残留物进行提纯分离。利用混合溶剂萃取的方法,对固定化脂肪酶(Novozym435)促合成的棕榈酸果糖单酯进行了提纯分离研究。结果表明,混合溶剂环己烷乙醇水萃取棕榈酸果糖单酯的纯度可达93.8%,收率达到92.5%,同时确定了萃取的最佳条件是V(环己烷):V(乙醇):V(水)=2∶2∶1,棕榈酸果糖单酯的初始质量浓度在0.48~0.60 mg/mL,温度为60℃。  相似文献   

6.
利用粒径分布为0.27~1.70 mm的煤质颗粒活性炭为吸附剂,采用固定床方式分离废弃液中的去乙酰头孢菌素C(DCPC)。以8%(体积)乙醇水溶液洗脱,得到DCPC纯度大于85%的洗脱液,收率为60%~65%。洗脱液经过纳滤膜浓缩后,通过阴离子交换树脂Amberlite IRA67吸附,以0.5 mol.L-1醋酸钠缓冲液(pH6.3)洗脱,得到DCPC纯度96%、含量大于30 g.L-1的去乙酰头孢菌素C的钠盐溶液,收率在90%~95%。加入丙酮,可得到去乙酰头孢菌素C钠盐结晶。以含有异丙醇的强碱溶液浸泡洗涤洗脱后的煤质颗粒活性炭,再用酸溶液中和冲洗,可恢复其吸附能力。  相似文献   

7.
龙德清  杨峰  陈胜胜 《应用化工》2005,34(12):774-775
研究了用酸性醇提取魔芋中生物碱的方法,通过氧化铝干柱层析法初步分离出了魔芋生物碱样品Ⅰ、Ⅱ和Ⅲ,样品Ⅰ的结构经1H NMR、IR和MS表征。  相似文献   

8.
报道了一种从含萘量较低的煤焦油中分离、提纯萘的有效方法。先用乙醇对煤焦油进行萃取,然后对萃出液减压蒸馏,得到含萘量较高的固液混合物,经过滤抽干得到粗萘。建立了水蒸汽蒸馏提纯粗萘的方法,所得的精萘经气相色谱检测其纯度可达99.48%,回收率在93%以上。随后与精馏法、溶剂结晶法等提纯方法进行了比较,体现了水蒸汽蒸馏提纯萘的优越性。  相似文献   

9.
Separation and purification of dodecanedioic acid (DDDA) from its homologous compounds were studied experimentally by falling film crystallization (FFC). The influences of various operation parameters, including crystallizing time, flow rate of melt and temperature of glycerine bath, on purity of DDDA and crystallizing rate were investigated. Over 99% (by mole) DDDA was obtained for a feed composition of 96% (by mole). The main factors affecting the separation efficiency are flow rate of melt and temperature of glycerine bath. The crystallizing layer of DDDA was further purified by sweating and blasting. A set of optimized operation data are provided for better understanding the mechanism of heat and mass transfer in FFC, and for further industrial application of DDDA purification process.  相似文献   

10.
对兽疫链球菌诱变株NW-162发酵液中透明质酸(HA)的分离提取工艺方法进行了对比研究。采用乙醇沉淀分离透明质酸、链霉蛋白酶酶解结合氯仿除去蛋白质及经氯代十六烷吡啶分级分离工艺,结果表明:乙醇与上清液的体积比为2.5∶1.0时沉淀透明质酸25 h最为经济;酶解结合氯仿去除蛋白质较氯仿单独作用时,透明质酸产量及纯度均有一定提高,再经氯代十六烷吡啶分级分离后,可得纯度为71.5%、蛋白质质量分数2.8%、产量0.747 g/L、相对分子质量725×103的透明质酸产品。  相似文献   

11.
高治平  李元  刘刚  何小珍  彭翔  莫青青 《陕西化工》2012,(9):1640-1641,1663
采用乙醇回流法提取马尾松松针儿茶素,获儿茶素含量为25.0%的粗提物,用金属离子沉淀-树脂吸附法分离纯化,得纯度为91.45%的儿茶素。用金属离子沉淀-树脂吸附法分离纯化松针乙醇粗提物中儿茶素,工艺简单、收率高、成本低、健康环保,有良好的应用前景。  相似文献   

12.
介绍了一种从含2-甲基萘量较低的洗油中分离、提纯2-甲基萘的有效方法。所得2-甲基萘经气相色谱分析其纯度可达99.5%,回收率在79.8%以上,此方法具有工艺简单、产物纯度高、污染低、共沸剂可以重复利用和成本低等特点。  相似文献   

13.
分离技术的进展   总被引:5,自引:0,他引:5  
李洲 《化工进展》1993,(1):17-22
本文概述了基于生物技术的发展、超纯材料的制备等对发展分离科学和技术的需求,特别是从大量基体物或稀溶液中提取、分离、纯化和检测低含量物质要求发展高选择性的分离技术和相应的分离体系。在发展和完善原有分离技术(如萃取、离子交换、吸附、吸收等)的同时,超临界萃取和膜分离技术具有引入的应用前景。还应注意两种或多种分离技术相结合的分离方法和技术的研究。  相似文献   

14.
The technologies of solvent extraction, ion exchange, and liquid membrane for the separation and purification of scandium are reviewed. Acidic and neutral organo‐phosphorus extractants are most widely used in practice, with high extraction efficiencies. Their disadvantages originate from the high stripping acidity required for the former and the poor selectivity for the latter. Carboxylic acids, amines, and acidic β‐diketone have also been widely used to extract scandium from solutions with low acidities. Mixed extractants or synergistic systems for the solvent extraction of scandium have been developed. Extraction efficiencies are influenced by extraction conditions such as aqueous matrixes and acidities, types of diluents and A/O ratios. Scandium(III) extractions are interfered with by commonly associated elements such as iron(III), zirconium(IV), titanium(IV), thorium(IV), yttrium(III) and lanthanides(III). The advantages and disadvantages of applications of ion exchange and liquid membrane technologies for scandium recovery are reviewed and compared with solvent extraction. Copyright © 2011 Society of Chemical Industry  相似文献   

15.
以甘油分别对甘蔗渣进行常压甘油自催化(AGO)预处理和常压甘油碱催化(al-AGO)预处理。利用酸沉法分别从预处理液中得到自催化甘油木质素(AGOL)和碱催化甘油木质素(al-AGOL)。利用单因素实验和正交实验得到最佳木质素提取工艺为转速8000r/min、离心时间15min、甘油混合液pH为3、甘油混合液浓度10%,在该条件下木质素AGOL和al-AGOL提取率分别达到72%和76%。采用扫描电镜(SEM)、元素分析、紫外光谱(UV)、凝胶色谱(GPC)、核磁共振1H谱、热重分析以及抗氧化活性分析等技术手段对提取得到的木质素进行结构表征。结果表明:从甘蔗渣中提取的球磨甘蔗木质素(MBL)、AGOL和al-AGOL主要呈现出球形特征;AGOL和al-AGOL具有相似的活性特点,与MBL相比,AGOL和al-AGOL的分子量更小、分布更窄、均一性更好,热稳定性和抗氧化活性更高,有望成为重要的工业原料。  相似文献   

16.
王磊  范肖南 《化学试剂》1996,18(5):301-303
报道了两个新的含硫杂环化合物萘并[2,1-b]噻吩和萘并[2,1-d]噻吩的合成,用元素分析、红外光谱、核磁共振谱及质谱表征产物的结构。  相似文献   

17.
The extracellular cellulolytic complex from Clostridium cellulolyticum H10 has been isolated and partially characterized. Through application of gel filtration and ion exchange chromatography techniques it has been established that in its native state this complex essentially consists of highly stable macromolecular structures (Mr c. 20 000 kDa) (similar to those described for different cellulolytic bacteria and currently termed cellulosomes) exhibiting avicelase, carboxymethylcellulase (CMCase) and xylanase activities. Furthermore, immunoaffinity assays show that this extracellular cellutosomal form of the complex is immunochemically similar to the cell-associated form. Another feature of the C. cellulolyticum H10 complex is that the Avicel-adsorbed fraction consists essentially of three major components, two of them (those of 160–170 and 72 kDa) having no detectable activity and one (that of 95 kDa) being associated with strong CMCase activity.  相似文献   

18.
苯甲酰肼在乙醇中,回流条件下,与芳醛和苯乙酮反应得到相应的酰腙(2a~2h),然后再进一步与乙酸酐环合,以良好的收率合成出了1,3,4-卟恶唑啉类衍生物(3a~3h)。通过元素分析,IR,1HNMR和MS对其结构进行表征,并对其裂解途径进行了探讨。  相似文献   

19.
苯并咪唑螯合树脂的性能与结构表征   总被引:1,自引:0,他引:1  
研究以环氧聚合物为基质的苯并咪唑螯合树脂的结构性能以及配位机制.已合成含有BBPAH的新型螯合树脂,测定其在pH 0~6.0的缓冲溶液中对Cu2、Ni2+、Zn2+、Cd2+和Co2+的配位容量.实验结果表明,在pH0~2.0条件下对Cu2+、Zn2+、Cb2+的配位容量分别为0.84、1.65、0.84 mmol/g,显示出很高的配位选择性.对络合Cu2+树脂进行了EPR表征和配位场的研究,初步证明为四面体配位结构.同时对苯并咪唑螯合树脂在强酸条件下吸附金属离子的机制进行了探讨.  相似文献   

20.
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