蚕蛹水解液的脱酸脱色研究

从蚕蛹中提取复合氨基酸的研究综观国内外文献报道主要在国内展开.我们深入分析了各位学者的研究成果,在此基础上展开了对蚕蛹水解液肥酸、脱色的试验工作,现愿以我们的实验结果为整个研究工作添上一笔.一、脱色研究蚕蛹水解液带有很深的酱油色,并有很浓的嗅味,在所见过的各篇报道大多采用活性炭脱色.我们采用了三种树脂和两种活性炭分别对水解液进行脱色,并用7520＃分光光度计测定脱色液透光率鉴定脱色效果,并对二个较好的脱色剂作正交试验得出影响脱色效果和脱色过程中氨基酸损失的主要因素,选出最佳脱色工艺条件.     

酶解法辅助提取花椒油树脂的工艺优化

试验以纤维素酶法辅助优化提取花椒油树脂。通过利用单因素和正交试验分析,结果表明,酶解温度为影响提取效果的显著因子,优化后提取条件为酶用量2.0mg/100mL,酶解时间1.5h,酶解温度45℃,在该工艺条件下提取一次花椒油树脂的平均提取率为30.2%。验证试验表明,经酶解提取法提取花椒油树脂与未经酶解处理的乙醇浸提法相比,结果增长25.8%。     

海参蛋白肽制备工艺优化及抗氧化性质

以海参为原料制备多肽,以水解度和羟自由基清除率为指标,从酸性蛋白酶、中性蛋白酶、碱性蛋白酶、木瓜蛋白酶筛选出最适酶并确定最优酶解工艺条件,测定所得多肽的抗氧化活性。结果表明,碱性蛋白酶制备海参多肽水解度明显高于其他蛋白酶,优化后的海参酶解工艺条件为:时间3.0h,加酶量4%,温度55℃,p H值为8.0,通过最优工艺参数验证实验,得到羟基自由基清除率为63.75%,表明用该工艺得到的活性肽具有较强抗氧化性,可作为制备海参多肽的工具酶。     

改性DGN丙烯酸树脂的研究

介绍了丙烯酸树脂及改性DGN丙烯酸树脂的研制方法，通过可控下的多种单体的聚合得到的共聚物，具有优良的涂饰特性。     

球孢白僵菌产几丁质酶液态发酵研究

对球孢白僵菌Bb174产几丁质酶的液态发酵条件进行了试验研究。选择麸皮和蚕蛹粉作为培养基的基本成分。以不同比例的麸皮和蚕蛹粉进行试验，结果显示：麸皮和蚕蛹粉分别为5％，培养温度28℃，接种量10％，装液量10mL，起始pH6．0，添加0．3％NaNO3对产几丁质酶有利，最高酶活力为4664U／mL。     

混合蛋白酶水解玉米蛋白的实验研究

研究了在不加碱pH渐变值条件下,经特殊热处理后,用枯草杆菌碱性蛋白酶和黑曲霉酸性蛋白酶混合水解玉米蛋白的方法,利用正交试验因素法考察了各种水解条件对玉米蛋白水解度和降解率的影响,并得出最佳水解条件是底物浓度80g／l,水解温度为55℃,碱性蛋白酶与底物比为50μl／g蛋白,酸性蛋白酶与底物比为8％（g／g）．利用反相高效液相色谱法测定水解产物氨基酸的成分,这些氨基酸包括人体,必需的八种氨基酸．     

从甘草中提取甘草酸和甘草次酸的工艺研究

采用水酸提取法从甘草中提取得到甘草酸粗品，用D101大孔树脂进行甘草酸的纯化，然后将甘草酸进行酸性加压水解得到甘草次酸。该方法工艺简便、产品收率与纯度高，树脂再生容易，是目前提取甘草酸和甘草次酸较为理想的方法。     

酶法水解动物蛋白工艺研究

用三种不同蛋白酶(胰蛋白酶和酸性蛋白酶)对猪肉在不同条件下进行酶解，利用甲醛滴定法对水解效果进行了对比。采用L18(37)确定两种蛋白酶水解猪肉的最佳工艺参数。     

环氧丙烯酸树脂合成工艺的改进

环氧改性丙烯酸树脂是先在环氧树脂分子链的两端引入丙烯酸不饱和双键,再以甲基丙烯酸甲酯、丙烯酸丁酯、苯乙烯等为混合单体,用过氧化苯甲酰为引发剂进行共聚而制得的一种改性树脂。用新型绿色溶剂取代传统的二甲苯等有毒溶剂,并对环氧丙烯酸树脂的合成工艺进行改进。     

浅议组成细胞有机物的构成元素和单体

本文就人教版高中生物学教材中关于组成细胞的有机物的单体以及有机物的组成元素谈几点认识。1如何理解“组成蛋白质的氨基酸约有20种”？迄今为止，从各种生物体中发现的氨基酸已有180多种，但是，     

米糠抗氧化肽的分离纯化研究

以DEAE-52离子交换柱层析和SephadexG-25凝胶过滤柱层析纯化米糠抗氧化肽,以硅胶G薄层层析测定其纯度,氨基酸自动分析仪测定其氨基酸组成。实验结果表明:米糠抗氧化肽经DEAE-52柱层析和Sephadex G-25柱层析后基本上得到了纯化;氨基酸组成分析表明,米糠抗氧化肽由14种氨基酸组成,富含两种酸性氨基酸:Asp、Glu,并含有6种人体必需氨基酸(Val、Met、Ile、Leu、Phe、Lys),占米糠抗氧化肽氨基酸总含量的31.89%,具有较高的营养价值和保健功能。     

珍珠贝肉酶解条件的优化探讨

以钦州珍珠贝肉为原料,以酶解液中氨基酸态氮含量作为指标,在单因素实验的基础上,通过正交实验来优化酶解工艺条件。结果表明：中性蛋白酶、碱性蛋白酶和胰蛋白酶3中酶中,碱性蛋白酶与胰蛋白酶进行双酶复合同步酶解效果较好,优化条件为：碱性蛋白酶与胰蛋白酶质量比为3∶2,温度50℃,pH7.5,酶解4h。在此条件下酶解液中氨基酸态氮含量为6.417mg/ml。     

电化学法测定西维因水解速率参数

使用现代电化学分析方法,通过监测水解产物的生成情况,研究了本身无电化学活性的西维因(甲萘威)在水中的水解情况,在pH=7.0的BR缓冲液环境中西维因水解产物检测的灵敏度最高.考察了环境酸度以及环境温度对水解的影响,并测定了不同条件下的水解速率常数.发现西维因的水解过程符合一级反应方程,其水解受pH值、温度的影响.在酸性介质中西维因仍有一定的水解,但是水解的速率明显低于碱性介质中的水解速率.同时,环境温度也会影响水解速率,在较高温度下,不论环境酸度值为碱性或者酸性,西维因的水解速率均有所升高.     

Affinity Purification of Insulin by Peptide-Ligand Affinity Chromatography

The affinity heptapeptide(HWWWPAS)for insulin,selected from phage display library,was coupled to EAH Sepharose 4B gel and packed to a 1-mL column.The column was used for the affinity purification of insulin from protein mixture and commercial insulin preparation.It was observed that the minor impurity in the commercial insulin was removed by the affinity chromatography.Nearly 40 mg of insulin could be purified with the 1-mL affinity column.The results revealed the high specificity and capacity of the affinity column for insulin purification.Moreover,based on the analysis of the amino acids in the peptide sequence,shorter peptides were designed and synthesized for insulin chromatography.As a result,HWWPS was found to be a good alternative to HWWWPAS,while the other two peptides with three or four amino acids showed weak affinity for insulin.The results indicated that the peptide sequence of HWWWPAS was quite conservative for specific binding of insulin.     

离子强度对盐类水解浓度平衡常数的影响

本文讨论了离子强度对盐类水解浓度平衡常数影响 ,指出在一定温度下 ,离子强度的增大 ,对一元弱酸强碱盐和强酸弱碱盐的水解浓度平衡常数趋向无影响 ;使一元弱酸弱碱盐的水解浓度平衡常数Kch 减小 ;对多元弱酸强碱盐的最后一级水解浓度平衡常数趋向无影响 ,其余各级水解浓平衡浓度平衡常数减小 ,以及相邻两级水解浓度平衡常数Kchi与Kch(i 1 ) 的比值减小     

AMINO ACIDS' PROTECTIVE EFFECTS ON EXPERIMENTAL ACUTE RENAL FAILURE

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AMINO ACIDS' PROTECTIVE EFFECTS ON EXPERIMENTAL ACUTE RENAL FAILURE

This study was carried out to elucidate the nephroprotective effects from a mixture of 8 L-amino acids and the possible mechanism of protection by this amino acid mixture. Acute renal failure model was induced by an intravenous administration of 10 mg/kg cisplatin to male Sprague-Dawley rats. A mixture of 8 L-amino acids or 0.9% saline was infused at a rate of 2 ml/h for 3 h, starting with a 2 ml bolus injection before cisplatin administration. Amino acids showed no acute effect on renal morphology. The infusion of a mixture of 8 L-amino acids increased GFR by 85% in control rats. The abnormalities of urine sodium and potassium excretion caused by cisplatin were markedly attenuated by the administration of the amino acid mixture. With the infusion of this amino acid mixture, cisplatin-induced abnormal state 4 respiration returned to control levels and the depressed state 3 respiration, respiratory control ratio and carbonyl cyanide p-trifluoromethoxyphenyl hydrazone-uncoupled respiration were ameliorated remarkably. A mixture of 8 L-amino acids showed marked nephroprotection against cisplatin-induced acute renal failure in rats and might function through augmentation of the cisplatin-injured renal mitochondrial electron transport-oxidative phosphorylation sequence, probably via stabilizing the membrane (including inner mitochondrial membrane) protein tertiary structure. In addition, this amino acid mixture remarkably increased GFR and decreased urine sodium excretion in rats.     

氨基酸N-酰化衍生物的合成与表征

用氯乙酰氯作为酰化剂在碱性条件下与氨基酸反应 ,通过改进反应条件 ,控温、调 p H值 ,选择萃取剂、洗涤剂、重结晶溶剂 ,使产品的纯度和产率有较大的提高 .用电喷雾电离质谱等先进手段对产品进行分析、鉴定 .同时对目标物作红外光谱及元素分析 .对化合物红外光谱进行了光谱归属     

Hg0 absorption in potassium persulfate solution

The aqueous phase oxidation of gaseous elemental mercury （Hg^0） by potassium persulfate （KPS） catalyzed by Ag^＋ was investigated using a glass bubble column reactor. Concentration of gaseous mercury and potassium persulfate were measured by cold vapor atom absorption （CVAA） and ion chromatograph （IC）, respectively. The effects of pH value, concentration of potassium persulfate and silver nitrate （SN）, temperature, Hg^0 concentration in the reactor inlet and tertiary butanol （TBA）, free radical scavenger, on the removal efficiency of Hg^0 were studied. The results showed that the removal efficiency of Hg^0 increased with increasing concentration of potassium persulfate and silver nitrate, while temperature and TBA were negatively effective. Furthermore, the removal efficiency of Hg^0 was much better in neutral solution than in both acidic and alkaline solution. But the influence of pH was almost eliminated by adding AgNO3. High Hg^0 concentration has positive effect. The possible reaction mechanism of gaseous mercury was also discussed.     

晾晒烟感赤星病后游离氨基酸含量的研究

不同品种晾晒烟接种赤星菌后,游离氮基酸含量也不同。随品种抗病性由弱到强,碱性、芳香族、杂环族三类基酸全病程病健比下降,酸性、脂肪族、侧链为非极性、侧链不带电极性四类氨基酸则上升,酪、赖、精、胱等氨基酸下降,苯、组、脯、蛋、谷、天、丝、苏、甘、缬、亮等氨基酸上升。品种抗性越强,苯、酪、赖、精、组、脯、胱等氨基酸上升越早,消减也越快。游离氨基酸总增值量也随品种抗性增强而增大。