鱼鳞盐酸脱钙过程中胶原蛋白含量的变化

研究了鱼鳞盐酸法脱钙过程中胶原蛋白的变化 ,经过和脱除液中总蛋白的比较可以看出 :当脱除液中盐酸浓度 <0 0 8mol/L时 ,胶原蛋白和总蛋白溶出具有同样的规律 ,即随着酸度的增加而增加 ;当盐酸的浓度 >0 1mol/L时 ,胶原蛋白溶出随着酸度的增加而降低 ,总蛋白仍然随着酸度的增加而增加 ,盐酸浓度为 0 0 8～ 0 1mol/L范围时 ,脱钙液中羟脯氨酸含量最高 ,胶原蛋白溶出最多。     

Antioxidants alleviate electric field-induced effects on lung tissue based on assays of heme oxygenase-1, protein carbonyl content, malondialdehyde, nitric oxide, and hydroxyproline

In order to test whether antioxidants have beneficiary effects on electric field induced damage, we determined the pulmonary levels of heme oxygenase-1 (HO-1), protein carbonyl content (PCO), malondialdehyde (MDA), nitric oxide (NO) and hydroxyproline (HP) under extremely low frequency (ELF) electric (E) field exposure (50 Hz, 12 kV/m, 7 days/for 8 h/day). While PCO levels significantly increased (p < 0.05), insignificant changes (p > 0.05) were observed in HO-1, MDA, NO and HP levels for electric field exposure groups compared to the control group. We have not observed any significant change in these parameters on the electric field group compared to the group where NAC and EGCG were separately applied along with electric field. However, during our previous studies, we have concluded that NAC and EGCG are potent antioxidants and we believe that new studies should be established by way of setting up different experimental conditions.     

Study of Selective Adsorption of Hydroxyproline on Chitosan-Hydroxyproline Resin Microspheres

In this article, chitosan-hydroxyproline resin microspheres (CHRM) were used as adsorbent for the separation of hydroxyproline (Hyp) from mixed amino acids. The optimum operating conditions (e.g., concentration of Hyp, pH of solution, and the optimum eluting agent) were determined by batch adsorption and elution of Hyp on CHRM. Under the optimum operating conditions, the effect of the flow rate of Hyp solution on dynamic adsorption and elution was studied. Furthermore, the selective adsorption property of CHRM for Hyp was investigated. The results indicate that Hyp can be effectively separated from mixed amino acids using CHRM as adsorbent. The hydrophobic interaction between the Hyp and CHRM play an important role in the selective adsorption.     

阿托伐他汀对自发性高血压大鼠心室重构的影响

目的: 观察阿托伐他汀对自发性高血压大鼠(SHR)心室重构的影响。方法: 24只SHR 随机分为4组,每组6只。SHR对照组、阿托伐他汀50mg组(50mg·kg^-1·d^-1)、阿托伐他汀10mg组(10 mg·kg^-1·d^-1)和缬沙坦组(20mg·kg^-1·d^-1);6只Wistar-Kyoto 大鼠(WKY)作为正常对照组。灌胃给药共6 周,分别于给药前和给药后每2 周测量大鼠尾动脉收缩压(SBP)。酶法测定血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)及低密度脂蛋白胆固醇(LDL-C)含量,放免法测定血浆和心肌血管紧张素Ⅱ(Ang Ⅱ)水平,并检测心肌羟脯氨酸、胶原蛋白含量和全心重量(HW)、左室重量(LVM)及左室重量指数(LVMI)。透射电镜观察心肌超微结构改变。结果: 用药前SHR 各组SBP均显著高于WKY 正常对照组(P<0.01),给药后第4、6 周,阿托伐他汀50 mg 组SBP明显下降(P<0.01),阿托伐他汀10 mg 组不明显;缬沙坦组自给药后第2 周,SBP明显下降(P<0.01)。阿托伐他汀50 mg 组TC、TG 及LDL-C水平较SHR 对照组明显降低(P<0.05或P<0.01),阿托伐他汀10 mg 组仅LDL-C 水平明显下降(P<0.05)。SHR对照组血浆Ang Ⅱ浓度与WKY 正常对照组比较无显著性差异,但心肌Ang Ⅱ浓度明显增高(P<0.05);给药6 周后,阿托伐他汀各剂量组和缬沙坦组血浆Ang Ⅱ浓度显著高于SHR 对照组(P<0.01),而心肌Ang Ⅱ 浓度在阿托伐他汀50 mg 组和缬沙坦组明显降低(P<0.05)。SHR 对照组心肌羟脯氨酸和胶原蛋白含量较WKY 正常对照组明显升高(P<0.01);6 周后,阿托伐他汀50 mg 组较SHR 对照组降低(P<0.05)。SHR组HW、LVM和LVMI与WKY正常对照组相比增高(P<0.01),而阿托伐他汀50 mg 组却低于SHR 对照组(P<0.05)。透射电镜观察心肌超微结构显示,阿托伐他汀50mg组和缬沙坦组与SHR对照组比较,心肌细胞核膜较完整,肌原纤维清晰,排列较整齐,横纹清楚,间质胶原纤维无明显增生。结论: 阿托伐他汀能明显改善SHR 的心室重构,降低血压和心肌Ang Ⅱ浓度可能为其机制之一。     

分光光度法测定畜禽骨素中胶原蛋白含量

本文提供了一种快速、简单、准确、成本低的畜禽骨素中胶原蛋白含量的测定方法。通过热法和酸法提取畜禽骨中胶原蛋白,计算其中胶原蛋白与羟脯氨酸含量的比值,得到不同原料骨的胶原蛋白换算系数：猪骨为6.12-6.17,牛骨为6.77,鸡骨为6.27-6.30,羊骨为6.34-6.35,结果表明水溶性和酸溶性的胶原蛋白换算系数差异不显著（P〉0.05）。根据骨素生产实际情况,选用水溶性胶原蛋白换算系数作为骨素中胶原蛋白测定的换算系数,用分光光度法测定热提骨素中羟脯氨酸含量,乘以对应的胶原蛋白换算系数,得到猪骨素、牛骨素和鸡骨素中胶原蛋白含量分别为9.19%、7.92%、9.78%。该方法测定骨素中胶原蛋白含量的相对标准偏差在0.01-0.03%之间,变异系数在0.44-2.26%之间,平均回收率在99.36-100.44%之间,说明分光光度法适用于骨素中胶原蛋白含量的测定。     

刺参体壁胶原蛋白的检测条件

为了缩短刺参体壁胶原蛋白含量的测定时间,简化实验操作,以及更加准确地检测刺参体壁胶原蛋白质中羟脯氨酸的质量分数,使得检测结果更为真实可靠,采用酸水解法分别对刺参体壁酶促溶性胶原蛋白和酸溶性胶原蛋白的水解条件进行了优化,在110、115、120、125和130℃分别水解2～30 h,确定其适宜水解时间为6 h,水解温度为120℃。在此水解条件下,对刺参体壁胶原蛋白中羟脯氨酸的质量分数进行了测定。结果表明,刺参体壁酶促溶性胶原蛋白中羟脯氨酸的质量分数为8.29%,酸溶性胶原蛋白中羟脯氨酸的质量分数为8.16%。     

Synthesis and characterization of a novel biodegradable polymer poly(lactic acid–glycolic acid‐4‐hydroxyproline)

The effect of certain preparative variables, such as the composition of the feeds, the reaction time, catalyst concentration, degrees Centigrade (°C), and the reaction temperature on the properties of prepared polymer poly(lactic acid–glycolic acid‐4‐hydroxyproline) (PLGA‐Hpr), was investigated via direct melt polymerization with stannous chloride as a catalyst activated by a proton acid. The new polymer had pendant amine functional groups along the polymer backbone chain. The results with regard to the inherent viscosity and yield of PLGA‐Hpr are discussed in relation to a recently proposed polymerization mechanism. The content of lactic acid, glycolic acid, and 4‐hydroxyproline (Hpr) in the copolymer was found to affect the surface and bulk hydrophilicity of various PLGA‐Hpr copolymers. The inherent viscosity of the copolymer and the yield of the reaction depended on the reaction temperature and varied with the reaction time. The higher the 4‐hydroxyproline content of the feedzaq, the lower the inherent viscosity of the copolymer and the yield of the reaction. When the glycolic acid content was more than 70% or the content of HPr was more than 10%, the polymer changed from hemicrystalline to amorphous. The in vitro degradation rate of the PLGA‐HPr copolymers is dependent on the feed ratios of lactic acid and glycolic acid in the polymer chain. Lactic acid‐rich polymers are more hydrophobic; subsequently they degrade more slowly. The structure of this polymer was verified by infrared (IR) spectroscopy, proton nuclear magnetic resonance (¹H‐NMR) spectroscopy, X‐ray diffractometry (XRD), and differential scanning calorimetry (DSC). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3585–3590, 2007     

高效液相色谱法检测酱油中羟脯氨酸的含量

实验建立了柱前衍生高效液相色谱分析酱油中羟脯氨酸(hydroxyproline,Hyp)含量的方法。样品经乙醇提取,以2,4-二硝基氟苯为衍生试剂,采用GeminiC18(4.6×250mm,5μm)色谱柱分离,检测波长为360nm。Hyp质量浓度与其峰面积在10～320mg/L范围内具有良好的线性关系,相关系数为0.9992。回收率为97.19%～110.18%,检出限为2.5mg/L。对实际样品中相对Hyp含量(表示为每克氨态氮中所含羟脯氨酸的毫克数)进行检测发现,纯酿造酱油在0.67～1.93mg/g之间,酸水解植物蛋白液在9.51～20.11mg/g之间,酸水解猪皮和猪肌肉分别为855.55,37.03mg/g,三类样品间存在较明显的差异。上述结果提示,Hyp并非胶原蛋白中所特有,但通过检测酱油样品中Hyp含量有可能区分酱油中是否添加酸水解蛋白液。     

鸡脚脱脂除杂蛋白预处理工艺

以脱脂率、胶原蛋白损失和除杂蛋白效果为指标,研究超声波辅助下对鸡脚进行脱脂除杂蛋白的预处理工艺,为从鸡脚中提取胶原蛋白提供基础。索氏提取法测定鸡脚处理前后脂肪含量,计算脱脂率;高效液相色谱法测定处鸡脚理前后羟脯氨酸、脯氨酸、甘氨酸含量,计算胶原蛋白损失和评价除杂蛋白效果。首先考察了V(石油醚):V(乙醇)=1:1/NaCl溶液法、碱性脂肪酶溶液法、NaOH溶液法对脱脂率的影响。对料液比及超声时间/次数进行优化,得出采用V(石油醚):V(乙醇)=1:1/NaCl溶液法脱脂率最高,其次为碱性脂肪酶溶液法、氢氧化钠溶液法,而NaOH溶液法胶原蛋白损失最大。进一步设计V(石油醚):V(乙醇)=1:1与碱性脂肪酶溶液结合的两步法,优化两步的料液比及超声次数/时间,获得较佳工艺为：第一步,V(石油醚):V(乙醇)=1:1,料液比1:4（g/mL）,超声萃取3次,每次用新的溶剂超声10 min;第二步,质量分数为2.5%的脂肪酶溶液（含0.05 mol/L NaOH,pH 8）,料液比1:2（g/mL）,超声处理40 min;脱脂率96.48%,胶原蛋白损失率9.31%,处理后鸡脚中羟脯氨酸、脯氨酸、甘氨酸占比与从鸡脚中热水提取的明胶相似,表明除杂蛋白选择性较好。     

分光光度法测定鱼皮中羟脯氨酸含量

采用分光光度法测定鱼皮（鱿鱼皮和狗鲑鱼皮）中的羟脯氨酸（Hyp）含量具有较高的准确度和精密度。采用该法测定两种鱼皮中羟脯氨酸的含量分别为0．823％和2．247％，平均回收率分别为98．47％和98．39％，变异系数分别为1．65％和0．64％。该法重复性好，可信度高，可作为判定鱼皮中胶原蛋白含量的一个定量指标。