由扩展青霉PF86产生脂肪酶催化油脂水解的研究

研究了由扩展青霉ＰＦ８６８产生脂肪酶催化水解三种油脂的影响因素与工艺条件,其中包括：水解时间、温度、ＰＨ、酶量、油水比及添加剂,并用气相色谱对产品脂肪酸进行了分析鉴定,初步分析其催化水解的脂肪酸的特异性。     

由扩展青霉(Penicillium expansum)PF868产生脂肪酶催化油脂水解的研究

研究了由扩展青霉（Ｐｅｎｉｃｉｌｉｕｍｅｘｐａｎｓｕｍ）ＰＦ８６８产生脂肪酶催化水解三种油脂（橄榄油、豆油、鱼油）的影响因素与工艺条件,其中包括：水解时间、温度、ｐＨ、酶量、油水比及添加剂,并用气相色谱对产品脂肪酸进行了分析鉴定,初步分析其催化水解的脂肪酸的特异性     

食源性抗氧化肽研究进展

生物活性肽主要水解自食源性蛋白质,此类活性物质表现出多种生物功能,其中尤以抗氧化能力最为突出。多项研究已证实抗氧化成分的摄入与疾病的发生呈逆相关关系。生物活性肽的抗氧化作用主要表现在自由基的清除能力、脂质过氧化的抑制能力以及金属离子的螯合能力。抗氧化活性的强弱取决于活性肽的结构及其特异性氨基酸序列。本文在对氧化应激的发生进行了介绍后,先后阐述了抗氧化肽的益生功能、酶法制备工艺、抗氧化活性的检测方法、生物利用度及其食用安全性。     

高压酶解卵清蛋白的工艺优化及其在BHK-21细胞培养中的初步应用

采用高压技术水解卵清蛋白,以水解度为指标,对6种酶的水解效果进行比较,筛选出最佳水解用酶;在单因素实验的基础上,采用正交实验的方法对高压酶解卵清蛋白的工艺进行优化,并对酶解产物在BHK-21细胞培养中的应用进行了初步探讨。结果表明:6种酶中胰酶的水解效果最好,水解最佳工艺为:压力120 MPa、温度50℃、p H值7.0和酶/底物(E/S)=1∶2.5(质量比),水解度达到45.13%;用酶解产物培养BHK-21细胞,细胞生长形态良好,在培养168 h后,试验组细胞最大密度达到6.69×105cells/m L,是对照组的1.56倍,细胞数量增大了33.45倍,说明卵清蛋白酶解产物有明显的促细胞生长效果,为其在细胞培养中的应用提供了理论依据。     

鲜猪血加压水解制备复合氨基酸新工艺的研究

采用正交试验方法,对鲜猪血加压水解制取复合氨基酸工艺条件进行优选。试验结果表明,采用鲜猪血加压水解制取复合氨基酸与采用猪血粉常压水解相比,简化了生产工序,缩短水解时间８～１２小时,降低能耗２倍多,减少硫酸用量２～３倍,而产品质量稳定可靠。     

脱氧核糖核酸对过氧化脂质和脂褐素生成的影响

实验探讨了脱氧核糖核酸（DNA）对小鼠心脏、肝脏和脑组织中的过氧化脂质（LPO）和脂褐素（Lf）生成的影响。结果表明,实验条件下所使用的脱氧核糖核酸可使小鼠体内过氧化脂质的生成明显减少,对脑和肝组织中脂褐素的生成有抑制效果。     

微波高压罐水解法在氨基酸分析中的应用简报

本文报导了采用微波高压罐水解技术快速水解食物蛋白质,并测定其１７种氨基酸含量的方法。研制的高压罐具有密闭性、微波穿透性好,耐热、耐压、耐腐蚀等特点。采用该高压罐研究了微波强度及作用时间等条件对氨基酸稳定性的影响,在微波输出功率１００Ｗ３５～４５分钟水解了３份食品样品,其氨基酸含量测定结果与传统的１１０℃２２左水解基本相符,１７种氨基酸５次平行测定结果ＣＶ值均＜１０％。     

补充谷氨酰胺对急性应激大鼠脑组织GSH、SOD和MDA含量的影响

目的：探讨谷氨酰胺对急性应激大鼠脑组织的抗氧化保护作用。方法：灌服Gln大鼠力竭性游泳后2h,检测其脑组织中谷胱甘肽(GSH)、超氧化物歧化酶(SOD)和丙二醛(MDA)含量的变化。结果：补充Gln大鼠力竭游泳后脑组织MDA含量显著下降。结论：补充Gln有助于减轻脑组织中的脂质过氧化反应。     

D-氨基葡萄糖硫酸盐水解条件的优化及组分分析

采用响应面分析法对H_2SO_4水解壳聚糖制备D-氨基葡萄糖胺硫酸盐工艺参数进行了优化,探索提取时间(min)、提取温度(℃)、物料比(m L/g)和H_2SO_4质量分数对D-氨基葡萄糖硫酸盐得率的影响,建立了提取D-氨基葡萄糖硫酸盐的二次项数学模型,得到最优提取工艺参数,并采用高效液相色谱-质谱联用仪(HPLC-MS)对H_2SO_4水解壳聚糖制备的组分进行初步分析。研究结果表明:H_2SO_4水解壳聚糖制备D-氨基葡萄糖硫酸盐的最佳工艺条件为H_2SO_4质量分数53.29%、物料比(m L/g)6∶1、温度88.31℃、时间6 h,在此工艺条件下的D-氨基葡萄糖硫酸盐得率为43.86%。影响D-氨基葡萄糖硫酸盐得率的因素主次顺序为温度、时间、H_2SO_4质量分数、物料比。用HPLC-MS测定提取物,首次发现H_2SO_4水解壳聚糖可得到D-氨基葡萄糖硫酸盐、葡萄糖胺和葡萄糖胺二聚糖硫酸盐混合物。     

木质纤维素预处理技术研究进展

详细评述了木质纤维素的预处理工艺研究进展,特别是浓酸低温水解-酸回收工艺、稀酸二阶段水解工艺、金属离子在稀酸水解过程中的助催化作用以及水蒸汽爆裂、氨纤维爆裂、CO2爆裂、酶催化水解等方法的研究进展情况。木质纤维素原料预处理技术发展为发酵生产乙醇技术的研究开发奠定了坚实基础。     

猪脑水解液的制备及其生物学活性研究

研究了猪脑水解液的制备及其生物学作用。结果表明:猪脑水解液含有17种氨基酸,其中包括8种必需氨基酸,总氨基酸含量为10493.9mg/L。实验组小鼠服用本品6天后,避暗试验和跳台试验的错误率明显下降(P<0.01),实验组大鼠服用28天后其脑重和雌性大鼠实验组血红蛋白水平显著高于对照组(P<0.05),雌性实验组大鼠在游泳30min后,血乳酸含量明显低于对照组(P<0.05)。提示猪脑水解液不但对脑营养价值高,而且能促进动物的被动学习能力和增强体质     

Study of rat brain tissue nucleases]

Acid and alkaline nucleases of the brain tissues have been identified and partially purified. Alkaline DNA-ase hydrolyzing denatured DNA at pH 8,0; alkaline RNA-ase having optimal activity at pH 8,0 and nuclease intensively hydrolyzing both DNA and RNA at pH 5.0. The molecular weights of these enzymes have been determined.     

The action of two classes of pyrethroids on the inhibition of brain Na-Ca and Ca + Mg ATP hydrolyzing activities of the American cockroach

Ca2+-stimulated ATP hydrolyzing activities (i.e. Na-Ca ATP hydrolysis and Ca + Mg ATP hydrolysis) measured in cockroach brain tissue were highly sensitive to the action of pyrethroid insecticides under in vitro conditions. Non-cyano-containing pyrethroids inhibited Na-Ca ATP hydrolysis to a greater extent than their cyano-containing counterparts. The reverse is true for pyrethroid action on Ca + Mg ATP hydrolysis. Nonmitochondrial Ca + Mg ATP hydrolysis of disrupted synaptosomes was the most sensitive activity examined. Ca2+-stimulated ATP hydrolyzing activities were inhibited in cockroaches poisoned by permethrin in vivo. In vivo poisoning occurred in the presence of a similar amount of bound [14C]permethrin which had been determined to cause a substantial amount of inhibition to Ca2+-stimulated ATP hydrolyzing activities in vitro.     

Effects of elevated plasma magnesium concentration on cerebrospinal fluid levels of magnesium in neonatal swine

To determine whether magnesium (Mg) can cross the blood brain barrier in developing swine, simultaneous measurements of [Mg] in plasma and cerebrospinal fluid (CSF) were made during experimental elevation of plasma [Mg] in 12 swine of differing postnatal age. All were anesthetized with Saffan and maintained at normal arterial blood gas composition. Aortic pressure and heart rate were monitored. Plasma and CSF samples, drawn at the beginning and end of a 60-min intravenous infusion of MgCl2 in all animals and every 10 min during the infusion in three, were analyzed for [Mg] and osmolality. CSF [Mg] increased in all animals as plasma [Mg] increased. There were no changes in CSF osmolality. The differences between plasma and CSF [Mg] was smallest in the youngest animals. These results indicate that Mg crosses the blood brain barrier in neonatal swine and suggest that the blood brain barrier is still maturing within the first postnatal month.     

Studies on the hydrolysis of 1-alk-1'-enyl-sn-glycero-3-phosphoethanolamine by microsomes from myelinating rat brain.

Microsomal fractions of 14-day-old rat brain were incubated at pH 7.1 with 1-[1'-14C]-alk-1'-enyl-sn-glycero-3-phosphoethanolamine (lysoplasmalogen). 1-[1'-14C]alkenylglycerol was produced by hydrolyzing enzyme activities, which were stimulated by Mg2 and inhibited by SH-group reagents. Hydrolysis of 1-[1'-14C]alkyl-sn-glycero-3-phosphoethanolamine is very similar in this respect, but the Km value is higher in the former case. The 1-alkyl compound acts as a non-competitive inhibitor of the hydrolyzing enzyme activity described, whereas the hydrolysis of the 1-alkyl derivative is not inhibited by the 1-alkenyl compound.     

Novel protease bound with chromatins in normal and tumorous tissues of rats

A protease capable of hydrolyzing casein with optimum pH 10 (alkaline protease), perhaps functional in hydrolysis of non-histone proteins and Hl histone, was found to exist at the state bound with chromatins of various normal and tumorous tissues of rats, in addition to the protease capable of hydrolyzing histone with optimum pH 8 (neutral protease). Alkaline protease was not observed in other subcellular fractions than nuclear fraction. It had approximately 18,000 daltons, and was chymotrypsin-like as inhibited by diisopropyl fluorophosphate, soybean trypsin inhibitor and Chymostatin. Its contents were significantly high in rapidly proliferating cells; Yoshida sarcoma? Rhodamine sarcoma≥ AH 130≥ thymus> spleen? kidney≥ liver? brain.     

High-Field Proton Magnetic Resonance Spectroscopy of a Swine Model for Axonal Injury

Abstract: A miniature swine model for diffuse brain injury has recently been developed that replicates the inertial loading conditions associated with rotational acceleration during automotive accidents. The swine model induces diffuse axonal pathology without macroscopic injury such as contusions and hematomas, thus affording a unique opportunity to study axonal injury with noninvasive techniques such as magnetic resonance imaging (MRI) and spectroscopy (MRS). In the present study, we evaluated this diffuse injury model with proton MRS, in vivo, using a high-field (4.0-T) MR scanner, since MRS has been demonstrated as a sensitive probe for detecting neurochemical abnormalities. Our study examined a region of the swine brain at timepoints before and after brain injury. Spectroscopic results indicate that N -acetylaspartate/creatine is diminished by at least 20% in regions of confirmed axonal pathology, whereas conventional MRI did not detect any abnormalities. These findings suggest that MRS has high sensitivity in diagnosing microscopic pathology following diffuse brain injury.     

Thiamine, thiamine phosphates and thiamine metabolizing enzymes in synaptosomes of rat brain

Thiamine and thiamine mono-, pyro- and triphosphate were found at detectable levels in synaptosomes isolated from whole rat brain. Synaptosomes prepared from whole brain, cerebellum and medulla were also found to contain uridine and inosine mono- and diphosphatases as well as the thiamine pyrophosphate synthetizing and hydrolyzing enzymes, but no thiamine monophosphatase. By isoelectric focusing on thin layer polyacrylamide gel of Triton X-100 homogenates of synaptosomes, thiamine pyrophosphatase activity could be separated into 10 bands with different isoelectric points. The contents of thiamine compounds and enzymes in synaptosomes were generally lower than those found in neuronal cell bodies.     

Clinical signs for identification of neurocysticercosis in swine naturally infected with Taenia solium

Taenia solium infection is a zoonotic disease and swine is the natural intermediate host. Till date no literatures have described clinical signs in swine indicative of brain involvement by cysticerci. In the present study we describe such clinical signs of porcine neurocysticercosis (NCC). These signs were excessive salivation, excessive blinking and tearing, and subconjunctival nodule. A total of 30 swine (18 with 2 or all 3 clinical signs and 12 without any sign) underwent magnetic resonance imaging (MRI). All 18 swine with above signs had NCC on MRI along with variable involvement of other organs that were subsequently confirmed by ex vivo MRI, necropsy and histopathology, while none of the 12 animals without any sign had NCC. As development of a porcine NCC model has proved difficult, we propose that naturally infected swine can be identified on the basis of these clinical signs and thus used as a model for further research on NCC.     

人天然免疫基因BCL10的猪同源物的识别、克隆与初步表达分析

采用电子克隆方法克隆到大小为925 bp的人天然免疫蛋白BCL10的猪同源基因完整cDNA序列(GenBank登录号：EU088132), 并利用RT-PCR方法从猪的全血中扩增出包含702 bp的完整开放读码框架(ORF)的cDNA片段。经核酸测序, 证明与电子克隆结果相符。利用NCBI BLAST分析该cDNA包含3个大小为57 bp、289 bp和356 bp的外显子, 并且定位于猪的4号染色体上。采用半定量PCR技术检测基础水平猪各组织BCL10基因mRNA表达丰度, 并将该基因构建到带有绿色标签的真核表达载体pEGFP-C1中, 采用脂质体转染法将该基因转入PK-15细胞, 通过绿色荧光标记和RT-PCR方法检测实验组的BCL10蛋白表达。研究结果表明, BCL10基因mRNA在脾脏中表达最高; 胸腺、大脑和淋巴结表达次之, 而肝脏只有微量表达, 肾脏没有检测到表达; 同时BCL10基因在PK-15细胞中得到了有效表达。