复方抗癌氨基酸注射液含量和稳定性研究

目的以色氨酸、精氨酸为主要成分研究复方抗癌氨基酸注射液。方法采用紫外分光光度法分析氨基酸注射液含量,考察注射液的稳定性。结果将抗癌氨基酸制成复方氨基酸注射液,其稳定性符合注射剂要求。结论复方抗癌氨基酸注射液的含量测定方法简单易行,经过光照、温度影响因素试验,稳定性良好,达到了液体制剂的要求。     

饮品与调味品中香味成分分析方法

饮品与调味品中的香味成分主要包括酯类、有机酸、糖类和氨基酸等。综述了这些成分的各种测定方法，重点介绍了气相色谱法（GC）、高效液相色谱法（耶LC）、离子色谱法（IC）和毛细管电泳法（CE）等当代先进的分析检测方法。     

酶法测定脂肪乳氨基酸（17）葡萄糖（11%）注射液氨基酸注射液中游离氨的含量

目的:建立脂肪乳氨基酸(17)葡萄糖(11%)注射液中氨基酸注射液游离氨的测定方法。方法:采用谷氨酸脱氢酶法测定。结果:在0～8μg范围内,氨的质量与吸光度之间线性关系良好;该方法的精密度、重复性和加样回收率的RSD值分别为0.34%、0.91%、1.2%。结论:该方法操作简便,可用于脂肪乳氨基酸(17)葡萄糖(11%)注射液中氨基酸注射液游离氨的测定。     

大豆主要抗营养因子检测方法的研究进展

大豆因其蛋白质含量高和氨基酸平衡性好,成为优质植物蛋白源应用于动物饲粮中。但大豆中存在的抗营养因子,限制其在饲粮中的利用效率,对动物生产也造成严重影响。本文综述了近年来,国内外关于蛋白酶抑制因子、大豆凝集素、大豆抗原蛋白三种抗营养因子检测方面的研究进展,使研究者进一步了解抗营养因子不同的活性测定方法的差异,为选择测定方法提供参考依据。     

用催化极谱法测定人发中的精氨酸

<正> 氨基酸是构成生物体的基本单元,是生命的物质基础。测定生物样品中氨基酸的含量,对于生命科学的研究具有重要意义。因此,寻找一种灵敏度高,稳定性好,宜于普及、推广的方法,一直是氨基酸测定方法研究中的重要课题。 J.M.Lopez Fonseca 等曾提出,精氨酸等15种氨基酸可以降低Ni~(2+)离子在滴汞     

专利文摘

检测阪崎肠杆菌的酶联免疫吸附测试方法及其中所用的抗体;半乳糖浓度的测定方法及半乳糖诊断试剂盒;氨基酸浓度的测定方法及氨基酸诊断试剂盒;新型酶促化学发光免疫检测系统;基于环介导等温扩增技术的沙门氏菌基因快速诊断试剂盒;环介导等温扩增技术的副溶血弧菌基因快速诊断试剂盒;使用动态表面生成和成像来检测生物和化学试剂的系统、方法和试剂;安氏隐孢子虫PCR检测试剂盒;基于聚二甲基硅氧烷的微型生物试剂分析检测芯片;含有经氧同位素标记的血红蛋白的生物体组织检测试剂及其制造方法;二步树脂法制备河豚毒素的方法及河豚毒素制剂。     

柱后衍生阳离子交换色谱法测定缤菲美肤养润抑菌凝胶中氨基酸的含量

采用阳离子交换色谱柱分离氨基酸,通过柱后衍生化检测分析,梯度洗脱,其中溶液泵(A泵)流速为0.50 mL/min,茚三酮泵(M泵)流速为0.25 mL/min,检测波长为440 nm (脯氨酸)和570 nm (其余氨基酸),进样量为50μL,建立了缤菲美肤养润抑菌凝胶中氨基酸的含量测定方法。结果表明,各氨基酸检测的线性关系良好;精密度(相对标准偏差,RSD)范围0.77%～1.30%,重复性(RSD)范围0.87%～1.96%;平均回收率范围95.81%～102.45%。所建立的分析方法准确,具有良好的重复性和回收率,可作为氨基酸的定量分析方法。     

气相色谱法测定N-脂肪酰氨基酸中游离脂肪酸

建立了气相色谱法测定N-脂肪酰氨基酸中游离脂肪酸含量的分析方法。用癸二酸作为内标,样品与三氟化硼甲醇溶液反应生成甲酯化合物,以HP-5色谱柱作为分析柱,FID作为检测器,用内标法定量。结果表明,脂肪酸质量在0.08～1.28 mg/mL范围内,其峰面积与质量呈现良好线性关系,相关系数r0.999,样品加标回收率为98.1%～105%。本方法可作为肪肪酰氨基酸中游离脂肪酸的快速测定方法,适用于肪酰氨基酸的质量控制。     

比较不同方法测定蔬菜中维生素C含量

蔬菜是人类不可缺少的重要食物,是人体维生素、矿物质、膳食纤维、氨基酸、蛋白质和糖等营养物质的重要来源。本实验是以蔬菜中维生素C含量的测定为对象,以西兰花、小白菜为样品,采用2,4-二硝基苯肼分光光度法和高效液相色谱及高效液相法为测定方法,旨在选定一种方法测定蔬菜中维生素C含量既快速、简便和准确度高的方法。实验结果表明:在两种测定方法中,西兰花中所含的维生素C比小白菜的多,而采用高效液相色谱法测定蔬菜中维生素C的方法结果准确,但耗时较长。     

红蓝草主要营养成分分析与评价

为红蓝草开发利用提供科学依据,采用食品安全国家标准的测定方法,对红蓝草嫩茎叶的营养物质、矿物质、蛋白质和氨基酸等含量进行测定分析,并与其他6种正在开发利用的植物进行比较。结果表明,红蓝草嫩茎叶的碳水化合物含量(28.92 g/100g)、粗蛋白含量(20.95 g/100g)和粗纤维含量(14.87 g/100 g)较高,含有一定量的活性成分总酚类物质(1.65 g/100 g)和总黄酮(0.83 g/100g),营养价值在6种植物中属中上水平。此外,其富含Ca、K、Mg、Na、P、Zn、Cu、Fe、Mn、Se等人体必需的多种矿质元素,其中Ca含量高于其余植物叶子,达5.84×104 mg/kg,是优良的补钙食物。氨基酸种类齐全且含量丰富,含有17种氨基酸,氨基酸总量为16.14 g/100 g,人体必需氨基酸总量为6.29 g/100g,药效氨基酸总量为9.45 g/100 g,占氨基酸总量的58.55%;氨基酸EAA/TAA与EAA/NEAA的值分别为39%和64%,非常接近于FAO/WHO建议的理想蛋白质标准;赖氨酸是第一限制氨基酸,必需氨基酸的SRC值为60.89,其蛋白质营养价值较高。有害金属元素Hg、Pb、Cd、As含量较低,符合食品安全标准对叶菜类的要求。结论:红蓝草含有丰富的碳水化合物,粗蛋白、粗纤维和多种人体必需的矿质元素,含有一定量的药理活性成分,氨基酸种类齐全且含量丰富,安全无毒,是一种兼具有营养和保健功能的优质食品资源。     

Analysis of functional groups in amino resins

Aiming at establishing recommended methods for the analysis of functional groups in amino resins, four tentative methods have been tested in an international cooperative exercise. The methods were employed on four model compounds and three commercial amino resin solutions. ¹³C-NMR spectroscopy was additionally employed by two of the participants.

The inter-laboratory analytical study has resulted in four recommended methods: 1. Solvent removal from amino resins, 2. Proton-NMR spectroscopy, 3. Alkoxy group analysis by transetherification plus G.L.C., 4. Alkoxy group analysis by Zeisel/Merz cleavage plus G.L.C. The recommended methods are improved versions of the tentative methods applied in the round robin and possible future inter-laboratory exercises will probably show a reduced variation between laboratories as far as quantitative results are concerned. As to qualitative analysis of amino resins, ¹³C-NMR spectroscopy has been shown to be a powerful technique.     

Determination of the amino acid tryptophan in protein fibres

Tryptophan can be used as an indicator amino acid for the photostability of proteins. The analysis of tryptophan and its degradation products is hampered by their instability in oxidative or strongly acidic media, or light. Various methods were employed to quantify tryptophan in wool and other protein fibres such as silk and human hair. Acid, alkaline and enzymatic methods were used to hydrolyse protein fibres. The amino acid tryptophan in wool and other protein fibres was determined by a colorimetric method, by amino acid analysis and by reversed-phase HPLC. The different analytical methods were compared with regard to their results. The colorimetric method (p-dimethylamino-benzaldehyde) proved to give reliable results for the tryptophan content in wool and unpigmented protein fibres. This method can be used also for wool dyed with acid, metal complex or reactive dyes or for pigmented keratin fibres after correction for a blank sample. Interference between dye and colorimetric reagent also have to be evaluated.     

SecProCT: In Silico Prediction of Human Secretory Proteins Based on Capsule Network and Transformer

Identifying secretory proteins from blood, saliva or other body fluids has become an effective method of diagnosing diseases. Existing secretory protein prediction methods are mainly based on conventional machine learning algorithms and are highly dependent on the feature set from the protein. In this article, we propose a deep learning model based on the capsule network and transformer architecture, SecProCT, to predict secretory proteins using only amino acid sequences. The proposed model was validated using cross-validation and achieved 0.921 and 0.892 accuracy for predicting blood-secretory proteins and saliva-secretory proteins, respectively. Meanwhile, the proposed model was validated on an independent test set and achieved 0.917 and 0.905 accuracy for predicting blood-secretory proteins and saliva-secretory proteins, respectively, which are better than conventional machine learning methods and other deep learning methods for biological sequence analysis. The main contributions of this article are as follows: (1) a deep learning model based on a capsule network and transformer architecture is proposed for predicting secretory proteins. The results of this model are better than the those of existing conventional machine learning methods and deep learning methods for biological sequence analysis; (2) only amino acid sequences are used in the proposed model, which overcomes the high dependence of existing methods on the annotated protein features; (3) the proposed model can accurately predict most experimentally verified secretory proteins and cancer protein biomarkers in blood and saliva.     

不对称转换方法制备D-型氨基酸

简述了D－型氨基酸的方法，化学不对称转换，生物不对称转换方法，制备D－型氨基酸的一般方法是先制备外消旋体，再进行拆分。根据拆分的手段和途径不同，分为物理拆分，化学拆分，生物拆分等。化学不对称转化是以L－型氨基酸或DL－型氨基酸为原料在拆分剂和催化剂共同存在下加热得到D－型氨基酸与拆分剂形成的盐，后者与碱反应得到D－型氨基酸。生物不对称转换包括两种情况，（1）不对称降解，即首先把DL－氨基酸衍生化。然后利用微生物产生的酶使氨基酸衍生物不对称水解。（2）水制备某一外消旋中间体，然后通过微生物体产生的消旋酶和水解酶在一定条件下使外消旋中间体转变为D－型氨基酸。     

氨基酸型两性表面活性剂的合成进展

氨基酸型两性表面活性剂是一类以生物物质为基础的环保表面活性剂。主要综述了两种羧酸基氨基酸型两性表面活性剂（N-烷基-β-丙氨酸和N-酰基氨基酸）的合成方法和合成进展,简述了磺基、硫酸基、磷酸基及其它氨基酸型两性表面活性剂的合成路线。指出环境友好的酶法和化学一酶法合成氨基酸型两性表面活性剂具有广阔的应用前景。     

Isolating the cuticle layer of wool: a comparison of methods

Various separation methods for cuticle isolation from whole wool have been studied. A method involving agitation of wool fibres in formic acid proved to be successful, producing a high yield of cuticle cells relatively free from contaminating cortical cells. The cuticle cells so isolated were characterised by amino acid analysis and scanning electron microscopy.     

油桐粕氨基酸分析和脱毒初探

采用水、醇、酸溶液处理桐粕 ,分析氨基酸含量 ,将处理后的桐粕制成复合饲料 ,并进行成鸡的饲喂实验 ,观察各方法的脱毒效果。结果表明 ,桐粕中粗蛋白的质量为干基质量的 35 % ,氨基酸的质量为干基质量的 2 9 0 3 % ;乙醇浸提时 ,浸出了极少的蛋白和有毒的含氮化合物 ,证明了桐毒为部分蛋白和含氮有机物     

微流控芯片电泳分析研究进展

综述了近年来微流控芯片技术设计加工、检测、应用方面的研究进展。主要包括电泳芯片制作的新方法、检测手段的创新以及在DNA、氨基酸、蛋白质、生物标记物、食品等方面的应用近况,并对微流控芯片电泳分析的发展进行了总结和展望。     

Species-Specific Chemical Signatures in Scale Insect Honeydew

The quantity and chemical composition of honeydew produced by scale insects may influence wider community structure, but little is known about the detailed chemical composition of the honeydew found in forest ecosystems. We used gas chromatography-mass spectrometry to examine the amino acid and carbohydrate composition of honeydew from three New Zealand communities. Low molecular weight carbohydrates (mono-, di-, and tri-saccharides) were derivatized using a modified trimethylsilyl (TMS) method, and amino and non-amino organic acids were derivatized using methylchloroformate (MCF). These recently developed derivatization methods allowed us to detect atypical compounds such as sugar alcohols, fatty acids, and non-amino organic acids, in addition to the more routinely studied compounds such as sugars and amino acids. Some compounds could not be identified and may be novel. Multivariate analysis showed that honeydew from each scale insect species had a distinctive amino acid and carbohydrate signature. We suggest these chemical signatures may influence the types of consumers that are attracted to different honeydews and may explain the characteristic communities associated with these honeydews.     

Designing amino acid sequences to fold with good hydrophobic cores

We present two methods for designing amino acid sequences ofproteins that will fold to have good hydrophobic cores. Giventhe coordinates of the desired target protein or polymer structure,the methods generate sequences of hydrophobic (H) and polar(P) monomers that are intended to fold to these structures.One method designs hydrophobic inside, polar outside; the otherminimizes an energy function in a sequence evolution process.The sequences generated by these methods agree at the levelof 60–80% of the sequence positions in 20 proteins inthe Protein Data Bank. A major challenge in protein design isto create sequences that can fold uniquely, i.e. to a singleconformation rather than to many. While an earlier lattice-basedsequence evolution method was shown not to design unique folders,our method generates unique folders in lattice model tests.These methods may also be useful in designing other types offoldable polymer not based on amino acids