胶原蛋白的应用

本文综述了胶原蛋白和多肽在生物，医学，食品，化妆品，饲料，化学品等工业中的进展，随着胶原蛋白与胶原多肽的生物功能等性能逐渐被人们认识，这方面的研究也逐渐成为研究的热点，利用动物皮开发新的生物产品将大大提高其附加值，具有广阔的发展前景。     

水溶液循环法尿素工艺技改生产多肽尿素

叙述水溶液循环法尿素生产工艺改产多肽尿素的工艺流程,并介绍了常见故障及其处理方法.     

Interaction of hIAPP with Model Raft Membranes and Pancreatic β‐Cells: Cytotoxicity of hIAPP Oligomers

Type II diabetes mellitus (T2DM) is associated with β‐cell failure, which correlates with the formation of pancreatic islet amyloid deposits. The human islet amyloid polypeptide (hIAPP) is the major component of islet amyloid and undergoes structural changes followed by self‐association and pathological tissue deposition during aggregation in T2DM. There is clear evidence that the aggregation process is accelerated in the presence of particular lipid membranes. Whereas hIAPP aggregation has been extensively studied in homogeneous model membrane systems, especially negatively charged lipid bilayers, information on the interaction of hIAPP with heterogeneous model raft membranes has been missing until now. In the present study, we focus on the principles of aggregation and amyloid formation of hIAPP in the presence of model raft membranes. Time‐lapse tapping mode AFM and confocal fluorescence microscopy experiments followed membrane permeabilization and localization of hIAPP in the raft membrane. Together with the ThT and WST‐1 assay, the data revealed elevated cytotoxicity of hIAPP oligomers on INS‐1E cells.     

水凝胶研究的最新进展

10余年来，有关刺激响应性水凝胶的理论和应用研究取得了长足的进展，在生物医学领域，水凝胶作为药物释放载体，软骨支架，细胞外基质更显示出巨大的应用前景。文中简要介绍了凝胶中水的特异性的研究进展，并综述了多糖和多肽凝胶的创建方法和其在组织工程中的应用。     

Dual‐pH Sensitive Charge‐Reversal Polypeptide Micelles for Tumor‐Triggered Targeting Uptake and Nuclear Drug Delivery

A novel dual‐pH sensitive charge‐reversal strategy is designed to deliver antitumor drugs targeting to tumor cells and to further promote the nuclei internalization by a stepwise response to the mildly acidic extracellular pH (≈6.5) of a tumor and endo/lysosome pH (≈5.0). Poly(l ‐lysine)‐block–poly(l ‐leucine) diblock copolymer is synthesized and the lysine amino residues are amidated by 2,3‐dimethylmaleic anhydride to form β‐carboxylic amide, making the polypeptides self‐assemble into negatively charged micelles. The amide can be hydrolyzed when exposed to the mildly acidic tumor extracellular environment, which makes the micelles switch to positively charged and they are then readily internalized by tumor cells. A nuclear targeting Tat peptide is further conjugated to the polypeptide via a click reaction. The Tat is amidated by succinyl chloride to mask its positive charge and cell‐penetrating function and thus to inhibit nonspecific cellular uptake. After the nanoparticles are internalized into the more acidic intracellular endo/lysosomes, the Tat succinyl amide is hydrolyzed to reactivate the Tat nuclear targeting function, promoting nanoparticle delivery into cell nuclei. This polypeptide nanocarrier facilitates tumor targeting and nuclear delivery simultaneously by simply modifying the lysine amino residues of polylysine and Tat into two different pH‐sensitive β‐carboxylic amides.     

~（125）I－酰化剂联结法标记人抑胃肽

实验证明，酰化剂联结法标记人抑胃肽（ＧＩＰ）能成功地保护ＧＩＰ免疫活性，其ＧＩＰ标记物与抗体５０％结合率时的效价为１：３×１０４，这为进一步建立ＧＩｐ的放免方法提供了条件。     

猪脾脏多肽的酶法制备及其生物活性研究

目的 探索酶解法制备猪脾脏多肽的最佳条件,检测所得产物的生物活性.方法 用胰酶酶解法、正交试验、甲醛滴定法考察最佳酶解条件,用乙醇沉淀法收集多肽,并分别用Fe2+诱发卵黄脂蛋白多不饱和脂肪酸过氧化体系和纤维蛋白平板法检测多肽的抗氧化活性和溶栓活性,CM-Sepharose离子交换层析纯化最佳酶解条件F的脾多肽,利用SDS-PAGE电泳确定具备促凝活性的多肽分子片段相对分子质量.结果 最佳酶解条件为60℃,pH 7.0,加酶量6.0%,时间5.5 h;检测到脾多肽具备抗氧化活性和促凝活性,经纯化后的脾多肽促凝时间比正常对照提前20 s.结论 可初步判断猪脾脏多肽在抗氧化和凝血方面有一定作用,且首次证实猪脾多肽具有凝血功能.     

酶解法制备大豆多肽的工艺研究

本实验以三种大豆制品豆饼、豆粉、豆皮为原料,选用Protease M"Amano"G酶作催化剂,探讨了分散浓度、分散时间、分散温度、水解温度、水解时间、水解pH值、酶用量等因素对酶解大豆多肽水解度(DH)、苦味和风味的影响.优选出了反应的最佳条件,并对三种原料酶解的最佳条件进行了比较,结果表明在水解度较大的情况下,大豆多肽有较好的风味并且无苦味.同时测定了大豆多肽的分子量分布和红外光谱.     

源于地龙蛋白的抗氧化肽鉴定与构效关系

为探究外源蛋白酶预酶解处理对地龙蛋白胃肠消化程度和胃肠消化后抗氧化活性的影响。该研究利用五种蛋白酶制备了不同的地龙蛋白酶解物,然后通过体外胃肠模拟消化探究这些酶解物的水解度、分子量分布和体外抗氧化活性的变化。五种蛋白酶酶解物中,碱性蛋白酶酶解物的水解度最高,为40.8%,其对DPPH、ABTS自由基的清除能力分别为27.36、175.46 μmol TE/g,ORAC值为0.70 μmol TE/mg。碱性蛋白酶酶解物经胃肠消化后的水解度、DPPH自由基清除率、ORAC值相比于地龙蛋白直接胃肠消化所得产物（EWP）分别提高了94.06%、72.21%及120.00%。GHEWP中鉴定出10 823条分子量<3 ku的肽,通过bioware.ucd.ie进行活性阈值评分筛选出活性评分最高的11个肽进行合成,验证活性,其中ATSGFFVY、HCFVLY、HLASGWY、HRYSDF、HYANMY的综合抗氧化能力较好,量子化学计算结果表明：ATSGFFVY、HCFVLY、HRYSDF、HYANMY的活性位点可能分别位于Tyr-8、Tyr-6、Tyr-3、Tyr-2上;HLASGWY的活性位点可能位于Trp-6上。该研究表明碱性蛋白酶预酶解可提高地龙蛋白的消化程度,增强其胃肠消化产物的抗氧化活性。     

猪血多肽亚铁螯合盐的体外抗氧化作用研究

研究了猪血多肽亚铁螯合盐对超氧阴离子自由基（O2-·）和过氧化氢（H2O2）的清除作用,并比较了维生素C、猪血多肽亚铁和猪血多肽对二者的清除能力。实验结果表明：猪血多肽亚铁螯合盐能清除超氧阴离子自由基（O2-·）和过氧化氢（H2O2）,维生素C、猪血多肽亚铁和猪血多肽这三种物质对超氧阴离子自由基（O2-·）和过氧化氢（H2O2）清除能力的强弱顺序为维生素C〉猪血多肽亚铁〉猪血多肽,故猪血多肽亚铁螯合盐具有较强的清除超氧阴离子自由基（O2-·）和过氧化氢（H2O2）的能力。