利用毛发水解提取氨酸后的废液研制氨基酸复合肥料

利用胱氨酸废液中游离氨基酸为主要成份研究氨基酸肥料,既解决了废液排放问题,又开辟了新的肥料来源。本文详尽叙述这一研制的工艺原则流,调添加剂在这一流程中的作用,并对氨基酸肥料的肥效进行了试验研究。     

二氯苯磺酸沉淀毛发水解液中亮氨酸和精氨酸的新方法

本文介绍了一种以二氯苯磺酸为沉淀剂从毛发水解液中分步沉淀亮氨酸和精氨酸的方法。利用两种沉淀形成速度的不同,通过控制反应条件,实现了亮氨酸和精氨酸的分步沉淀,确定了沉淀条件对目标氨基酸沉淀效率的影响,得到合适的工艺条件:200g人发,水解得400mL水解液;加50g二氯苯磺酸沉淀剂,在5℃加晶种,间歇搅拌12h,过滤得亮氨酸复合物沉淀;在沉淀亮氨酸之后的母液中再加50g二氯苯磺酸沉淀剂,于相同的温度条件下加晶种,连续搅拌至生成稠厚的沉淀,再静置沉淀12h,过滤得精氨酸复合物沉淀。亮氨酸的沉淀率为71.0%,母液中残留亮氨酸浓度为7.6g/L;精氨酸的沉淀率为76.6%,母液中残留精氨酸浓度为8.9g/L。     

角蛋白水解液中L-胱氨酸含量测定方法的比较研究

比较研究了用碘量法和分光光度法测定角蛋白水解液中Ｌ－胱氨酸含量的适用性。结果表明,磺量法不适用于水解液中Ｌ－胱氨酸含量的测定。分光光度法不仅适用于水解液中Ｌ－胱氨酸含量的测定,同时也适用于产品Ｌ－胱氨酸含量的测定,测定结果准确可靠,相对误差为０．２９％～０．８４％。     

蚕蛹水解液的氨基酸分组分离法

采用７３２、７１７树脂对蚕蛹酸水解液进行分离。７３２树脂先将蚕蛹水解液粗略分成酸性、中性、碱性氨基酸,７１７树脂再将中性氨基酸分成甘氨酸－丙氨组酸和亮氨酸－异亮氨酸－缬氨酸组。其中亮、异亮、缬氨酸的含量达到７５．９％;同时还进行了脯氨酸的分离,经７１７树脂分离得到的脯氨酸的含量为５０．６％。     

植物非蛋白氨基酸的化学结构

植物非蛋白氨基酸的化学结构吴晓东杨兴洪张连忠（中国农业大学生物学院，北京１０００９４）ＣＨＥＭＩＣＡＬＳＴＲＵＣＴＵＲＥＯＦＰＬＡＮＴＮＯＮＰＲＯＴＥＩＮＡＭＩＮＯＡＣＩＤＳＷｕＸｉａｏ－ｄｏｎｇＹａｎｇＸｉｎｇ－ｈｏｎｇＺｈａｎｇＬｉａｎ－ｚｈｏ...     

纯化HuIFN—α蛋白含量测定方法的研究

本文对Ｋｊｅｌｄａｔｈ氏,Ｌｏｗｒｙ氏及Ｋａｌｃｋａｒ氏三种测定纯化α型人白细胞干扰ｕＩＮＦ－α）蛋白南含量的方法进行了比较试验和研究。Ｋｊｅｌｄａｈｌ氏法测定结果准确可靠,但样品用量大,费时,Ｌｏｒｒｙ氏法与Ｋｊｅｌｄａｈｌ结果一致,榈一少,结果稳定：ａｌｃｋａｒ氏法操作简单方便,样品用量少,但误差较大作者改良了Ｋａｌｃｋａｒ氏法,测定误差大为下降。纯化ＨｕＩＮＦ－α与人血清白蛋白（ＨＳＡ）,牛     

由铬革屑制备可溶性蛋白及氨基酸的研究

成品铬革屑中蛋白质含量在 70 %以上 ,处理成小颗粒后与水、Ca(OH) 2 按 1∶4 0∶0 .4的比例混合 ,90℃反应 5h ,可溶性蛋白转化率近 6 0 % ,且在升温后加入Ca(OH) 2 有利于退鞣。以 6mol/L盐酸水解皮革蛋白粉制备复合氨基酸 ,水解 14h ,水解液以HD -I树脂脱色 ,氨基酸损失较少 ,且动态脱色效率明显高于静态脱色 ,采用 717树脂脱酸可获得pH4 .5 - 5的复合氨基酸溶液 ,总得率为 6 0 .1%。     

罗汉果蛋白质的含量测定

对罗汉果三个栽培品种的蛋白质和氨基酸进行了含量测定,从水解产物中检出了18种氨基酸。     

A comparison of15N proline and13C leucine for monitoring protein biosynthesis in the skin

Summary The tracers L¹⁵N-proline and L(1-¹³C)-leucine were used to explore the synthesis of skin proteins in vivo in rabbits. They orally received a single dose containing an equimolecular mixture of L(1-¹³C)-leucine and L¹⁵N-proline. The changes in the amounts of these tracers in blood and skin were monitored for a total of 8 h. The data showed the appearance of the two tracers in blood within 15 min and their clearance in 8h. They were both rapidly (15 min) incorporated into skin proteins, but more proline was incorporated than leucine. We therefore consider L¹⁵N-proline to be a better tracer than L(1-¹³C)-leucine for studying protein metabolism in the skin.     

Quantitative determination of free intracellular amino acids in single human polymorphonuclear leucocytes: Recent developments in sample preparation and high-performance liquid chromatography

The described procedure allows quantitative, highly precise and reproducible analysis of free amino acid concentrations in single polymorphonuclear leucocytes (PMLs). This method is superior to previously described procedures with regard to sample size, PML separation, sample preparation and stability, as well as the chosen fluorescence high-performance liquid chromatography procedure, and can satisfy the high demands for ultra-sensitive and comprehensive amino acid analysis, especially for the continuous surveillance of severe diseases and organ dysfunction.     

Chiral separation of amino acids in biological fluids by micellar electrokinetic chromatography with laser-induced fluorescence detection

A method is presented for the chiral analysis of amino acids in biological fluids using micellar electrokinetic chromatography (MEKC) and laser-induced fluorescence (LIF). The amino acids are derivatized with the chiral reagent (+/−)-1-(9-anthryl)-2-propyl chloroformate (APOC) and separated using a mixed micellar separation system. No tedious pre-purification of samples is required. The excellent separation efficiency and good detection capabilities of the MEKC-LIF system are exemplified in the analysis of urine and cerebrospinal fluid. This is the first time MEKC has been reported for chiral analysis of amino acids in biological fluids. The amino acids -alanine, -glutamine, and -aspartic acid have been observed in cerebrospinal fluid, and -alanine and -glutamic acid in urine. To the best of our knowledge no measurements of either -alanine in cerebrospinal fluid or -glutamic acid in urine have been presented in the literature before.     

The use of a new silica gel separation system in thin-layer chromatography

Summary A new method for the chromatography of amino acids is described in which D- or L-amino acids are separated on ICT-Empore thin-layers. The compounds are developed ascending by means of normally used solvent systems. An overloading of the plates is nearly impossible. On the other hand, hydrophilic amino acids are well separated. A second front, moving with these amino acids and emerging with ninhydrin stain, was not detectable.     

Development of a protocol for the automated analysis of amino acids in brain tissue samples and microdialysates

An automated precolumn derivatisation method has been developed for the measurement of fourteen amino acids in brain tissue and microdialysate samples. The method involves labelling amino acids with naphthalene-2,3-dicarboxaldehyde (NDA) in the presence of cyanide (CN⁻). The resulting highly stable N-substituted 1-cyanobenz[f]isoindole (CBI) derivatives were separated using a binary gradient elution profile and detected fluorometrically. The order of elution of the derivatised amino acids was confirmed by using liquid chromatography with fluorescence and mass spectrometric detection in tandem. Linear calibration plots were obtained for all amino acids in the range studied (0.2–12.5 μM). The limit of detection for CBI derivatives of amino acids was in the range 5–20 fmol (S/N=2) using a 5 μl injection volume. The method has been used for the measurement of amino acids in microdialysates from rat brain and tissue homogenates from different regions of mouse brain.     

Synthesis of adhesive protein from the vitellaria of the liver flukeFasciola hepatica

Summary The polynonapeptide (Gly-Gly-Gly-Tyr-Gly-Gly-Tyr-Gly-Lys)_n, which is a precursor sequence of adhesive protein from the vitellaria of the liver flukeFasciola hepatica has been synthesized by the fragment coupling, followed by polycondensation, and by cleavage of the protecting groups by hydrogen bromide. The synthetic adhesive protein was estimated to have the molecular weight of 10,100 (12 repeating units as nonapeptide) and was found to have satisfactory amino acid compositions. The Tyr residues of the synthesized precursor polynonapeptides can be converted to the Dopa residues by tyrosinase, giving the synthetic adhesive protein of the liver fluke.