以动物羽毛为原料制备饲用氨基酸的进展

综述了用酶和化学方法处理羽毛制备饲用氨基酸的进展及应用。羽毛的蛋白含量极高。是家畜的重要蛋白源。但是羽毛中含有大量的含胱氨酸的角蛋白，胱氨酸中含有二硫键。非反刍动物难以消化利用，因此，降解角蛋白为易消化吸收的氨基酸使其成为常规饲料，使废物充分利用，特别是合理利用蛋白质资源、开发角蛋白具有重要意义。     

Optimization of amino acids production from waste fish entrails by hydrolysis in sub and supercritical water

A resource recovery technique using sub‐ and supercritical water hydrolysis was applied to convert waste fish entrails into amino acids. The effect of reaction parameters such as temperature and time necessary for the control of reaction towards optimum yield of amino acids was investigated. Results showed a maximum yield of total amino acids (137 mg/g dry fish) from waste fish entrails at T= 523 K (P = 4 MPa) and reaction time of 60 min in a batch reactor. Under supercritical conditions (e. g., T= 653 K, P = 45 MPa), the yield decreases due to rapid decomposition compared to production rate of amino acids. The results suggest operation of the system at short reaction time and mild temperature condition.     

Potential-controlled chromatography for the separation of amino acids and peptides

Potential-controlled chromatography is introduced as a new technique for the separation of amino acids and peptides. The principle of potential-controlled chromatography depends on the use of electrically conductive material as the stationary phase of the chromatographic column. Thus from an electrochemical point of view the packed column can be regarded as a packed-bed electrode. The electrical potential of this stationary phase can be controlled by a potentiostat. The separation of amino acid and peptide molecules during their migration through the column depends on their own electric charge on the one hand and on the electrical potential of the stationary phase on the other. The chromatographic separation of some amino acids could be demonstrated.     

我国氨基酸与活性肽的提取精制技术进展

介绍了微滤膜、离子交换模拟移动床（SMB）、超滤膜、连续结晶、非极性吸附层析模拟移动床等现代分离技术。并介绍了用现代分离技术改造氨基酸与活性肽提取精制工艺的最新进展与成果。     

Combination of allyl protection and HYCRAMTM-linker technology for the synthesis of peptides with problematical amino acids and sequences

Analogues of both the nonapeptides, bradykinin and bradykinin potentiating nonapeptide BPP_9α, were synthesized using HYCRAM^TM-technique. The bradykinin analogues were assembled by the Boc-, Ddz- and Fmoc-strategy starting with Boc-Arg(Aloc)₂-OCr–OH, Ddz-Arg(Mtr)-OCr–OH and Fmoc–Arg(Mtr)-OCr–OH. While Boc- and Ddz-strategy provide peptides in good yield and purity, the Fmoc-strategy leads to a loss of peptide from resin. For simultaneous cleavage from HYCRAM^TM-resin and removal of Aloc-side chain protection optimized conditions for catalytic cleavage with Pd° were developed. As shown by the synthesis of BPP_9αanalogues the HYCRAM^TM-linker and the chlorotrityl resin allow the assembly of peptides with the C-terminal sequence Pro-Pro by preventing dioxopiperazine formation. Since the BPP_9α sequence contains the tripeptide Trp-X-Arg an intramolecular migration of the N^G-protecting group to the indole ring under conditions used for its removal had to be avoided. By the use of HYCRAM^TM-linker in combination with Aloc protection for the guanidino group and Ddz for N^αno modification of Trp occurred. HYCRAM^TM-technology in combination with Boc-, Ddz- or Aloc/All-protecting groups facilitates the synthesis of peptides with such very labile amino acids like cis-4-hydroxyproline.     

近临界水中禽类废弃物超低酸水解成氨基酸

为寻求禽类废弃物的有效利用途径,对其进行在近临界水中超低酸水解制备氨基酸的工艺优化及反应动力学研究。以鸡肠为原料,氨基酸总收率为指标,采用正交试验设计对反应温度、反应时间、硫酸浓度3种水解条件进行研究。实验结果表明,近临界超低酸水解法最佳的工艺条件为:T=533 K,t=28 min,c(H2SO4)=0.002 mol/L,氨基酸的总收率为11.49%。在反应温度分别为473,503,533,553 K,c(H2SO4)=0.002 mol/L条件下,鸡肠在近临界水中水解为氨基酸的动力学表观速率常数分别为1.52×10-2,3.35×10-2,11.58×10-2,14.01×10-2。其反应级数为1.52,反应活化能为64.44 kJ/mol,指前因子为1.91×105。     

近临界水中鱼肉水解制备氨基酸的反应动力学

利用鱼肉蛋白制备氨基酸不但具有经济效益,而且为生物质资源高效利用提供技术支持。采用HL-F(0.2 L+1.5 MG)/30 MPa-IIA超临界水反应装置,在无催化剂、反应温度分别为220,240,260℃,反应时间为30 min条件下,对鱼肉蛋白在近临界水中水解为氨基酸的反应动力学进行了实验研究。用AAA-Direct氨基酸分析仪测定不同反应时间中氨基酸总产率,以酸水解鱼肉蛋白得到的氨基酸量为完全水解标准。在水过量的情况下,得到了鱼肉蛋白水解率宏观反应动力学方程。结果表明鱼肉蛋白水解动力学的级数为1.614 7,220,240,260℃下的反应速率常数分别为0.001 7,0.004 5,0.009 7,活化能为145.125 kJ/mol,前置因子A为9.475 7×109,为工业化生产提供了基础数据。     

离子液体作薄层色谱添加剂对氨基酸分离的研究

将1-丁基-3-甲基咪唑基四氟硼酸盐([Bmim]BF4)离子液体作为薄层色谱展开剂添加剂,讨论了[Bmim]BF4浓度对精氨酸和赖氨酸两种碱性氨基酸分离的影响.结果表明:添加离子液体能有效改善碱性氨基酸的展开效果,而且分析物的Rf值随离子液体浓度的增加而增加,浓度增加到一定后Rf保持不变.另外,比较了[Bmim]PF...     

氨基酸分离提纯的研究进展

本文对氨基酸分离提纯常用的沉淀法、离子交换法、萃取法、吸附法等方法的原理及研究进展状况作了较全面的总结。     

Separation and identification of amino acids from lignite humic acids by thin layer chromatography

Thin layer chromatography with and without temperature gradient was used to identify ten amino acids in the humic acid hydrolysate of Rovinari lignite, using cellulose and volcanic tuff as stationary phases. The acids found were L-leucine, isoleucine, phenylalanine, L-valine, tyrosine, proline, L-alanine, glutamic acid, threonine and L-lysine.     

用聚酯材料制备高固体分聚酯/氨基烘漆

以废聚酯材料为原料,经过醇解、酯化,制成高固体分高羟基聚酯树脂,再与高固体分氨基树脂配合,制成高固体分聚酯/氨基清漆或磁漆,其具有较高的施工固体分和出色的涂膜性能。简述了涂料配方、生产工艺和产品性能,分析了该涂料的经济效益和社会效益。     

硅酸盐色谱分离中性氨基酸性能研究

将硅酸钠与硫酸铜或硫酸锌按等体积混合 ,制得新型无机离子交换剂硅酸铜、硅酸锌 ,分别用其作为色谱载体对中性氨基酸 (甘氨酸 ,丙氨酸 )进行分离 ,与强酸性阳离子交换树脂 0 0 1× 7的色谱行为作了比较。结果表明 ,合成的硅酸盐具有较好的分离性能。通过不同载体分离中性氨基酸 (甘氨酸 ,丙氨酸 )的流出体积的比较 ,硅酸铜的流出体积大于硅酸锌 ,硅酸锌的流出体积大于 0 0 1× 7。结果显示 ,硅酸铜比硅酸锌更适合于分离中性氨基酸 ,具有最好的分离特性     

Enantioselective separation of basic amino acids on talc

Certain amino acid derivatives (ε-basic, anilide group) can be readily adsorbed onto various types of talc (steopac, SS20, C300, C400). For instance, talc is capable of adsorbing the amino acid esters but not the equivalent free amino acids. The types of talc which have high hydrophobicity (00, 15M00) were poor adsorbents. Two applications of these findings are presented: enhancement of the sensitivity of enzymatic tests in the presence of chromogenic substrates and enantioselective separation of ε-basic amino acids (arginine, lysine, ornithine).     

表面活性剂双水相萃取分离氨基酸研究

用溴化十二烷基三乙铵(C12NE)与十二烷基硫钠(SDS)混合体系形成双水相,测定混合摩尔比与分相比例的关系,并以苯丙氨酸为萃取对象研究其在双水相体系中的分配及多级错流萃取效果。实验结果表明,当C12NE与SDS摩尔比为(1.6∶1)—(1.7∶1)时体系有分相,其中当C12NE与SDS摩尔比为1.65∶1时,分相所得上下相体积比为1∶1,且分相时间为10 m in左右,为适合实验条件。双水相体系萃取苯丙氨酸的结果表明,单级萃取率可达80%以上,二级萃取率可达99%以上。     

Supernovae, neutrinos and the chirality of amino acids

A mechanism for creating an enantioenrichment in the amino acids, the building blocks of the proteins, that involves global selection of one handedness by interactions between the amino acids and neutrinos from core-collapse supernovae is defined. The chiral selection involves the dependence of the interaction cross sections on the orientations of the spins of the neutrinos and the (14)N nuclei in the amino acids, or in precursor molecules, which in turn couple to the molecular chirality. It also requires an asymmetric distribution of neutrinos emitted from the supernova. The subsequent chemical evolution and galactic mixing would ultimately populate the Galaxy with the selected species. The resulting amino acids could either be the source thereof on Earth, or could have triggered the chirality that was ultimately achieved for Earth's proteinaceous amino acids.