NaCl盐析法从猪血粉水解液中提取L-亮氨酸

以NaCl为盐析剂从猪血粉水解液中盐析沉淀L-亮氨酸,确定了盐析沉淀所需的时间,考察了温度、pH值、NaCl加入量等因素对L-亮氨酸盐析沉淀率的影响。结果表明:盐析剂NaCl在原料液全溶解后搅拌半小时盐析沉淀率基本上达到最大值;低温对于盐析沉淀是有利的,工业生产中可在室温下或低温下进行;在溶液的pH值约为2时,NaCl存在下L-亮氨酸以二亮氨酸盐酸盐形式析出,沉淀率达到最大;溶液中氯化钠浓度越高盐析沉淀率越高,工业生产上可按0.35g/mL的比例加入NaCl。室温下控制猪血粉水解液的pH值为2,按0.35g/mL原料液的比例加入NaCl盐析出二亮氨酸盐酸盐,经精制得L-亮氨酸产品,产品符合《中华人民共和国药典》(2000年版二部)质量标准,L-亮氨酸的平均提取率为82.36%。     

正交实验法优化黄连中小檗碱盐析提取工艺

采用正交实验法对黄连中小檗碱盐析提取的浸泡时间、黄连粒度、硫酸浓度、HCl调pH值、石灰乳调pH值及NaCl用量等影响因素进行了优化。确定最优的提取方案为:浸泡时间24 h、黄连粒度0.355～0.5 mm、硫酸浓度0.40%,固液比1∶16、石灰乳调pH值12、HCl调pH值5、NaCl用量25%,在此条件下,小檗碱产率为8.4%、纯度为72.7%。各因素对黄连小檗碱提取效果影响大小依次为:固液比硫酸浓度浸泡时间黄连粒度NaCl用量石灰乳调pH值HCl调pH值。     

废弃毕赤酵母核糖核酸提取条件的优化

为了确定废弃毕赤酵母提取核糖核酸的提取工艺条件,首先通过单因素试验研究了溶液pH、酵母浓度、抽提温度和抽提时间对毕赤酵母核糖核酸提取的影响,然后采用正交试验分析法对提取核糖核酸的影响因素进行了优化。优化结果表明,毕赤酵母核糖核酸提取的最佳工艺条件为:酵母浓度为3%,pH=10,抽提温度为100℃,抽提时间为2.5 h,在此条件下,核糖核酸的提取率可达3.11%。     

常见热带水果芒果果皮中果胶的提取

本文在单因素试验基础上,选取酸解pH值、酸解温度、盐析pH值、盐析温度作为考察因素,以果胶得率为指标进行正交试验,确定芒果皮果胶提取的最佳工艺参数。结果发现最佳提取工艺条件为酸解pH值为3,酸解温度为95℃,盐析pH值为5,盐析温度为40℃。     

龙虾虾壳蛋白质提取条件的研究

根据蛋白质溶液的pH值在某一值时蛋白质的静电荷为零，且蛋白质溶液溶于水形成胶体溶液，在该溶液中加入无机盐后，利用蛋白质盐析的原理分离蛋白质。实验以NaOH质量分数、反应时间、反应温度为三因素，提取出蛋白质，通过一系列实验，找出最佳反应条件。     

溶菌酶结晶法提取及其酶活力的探讨

以湖光岩鹌鹑蛋为原料,采用结晶法从蛋清中分离提取溶菌酶。探讨不同条件对溶菌酶收率及活性的影响,确定溶菌酶最佳的分离提取条件:盐析Na Cl质量分数为5.1%,pH=10.7,盐析时间为120h,收率达到0.378%,酶活力达到13700 U/mg。     

蛋壳型催化剂结构、制备方法及其催化性能影响因素分析

综述了蛋壳型催化剂结构及制备方法,并对蛋壳型催化剂的浸渍制备法和制备过程中的影响因素如溶液浓度、溶剂极性、浸渍时问、溶液pH值和载体等进行了总结和评述.介绍了活性组分呈蛋壳型分布对催化剂性能的影响以及活性组分最优分布状态理论.     

BⅢ型聚表剂缔合行为影响因素

荧光探针法是研究疏水缔合聚合物缔合行为的常用方法,采用芘荧光探针法研究浓度、剪切作用、pH值和NaCl对B_Ⅲ型聚表剂溶液缔合行为的影响,结果表明:增加聚表剂浓度和NaCl浓度可增强缔合行为;剪切会导致缔合行为变弱,但仍能依靠聚表剂分子链内和链间缔合作用形成缔合结构;pH值小于5时,溶液缔合行为随pH值增大逐渐减弱且幅度较大;pH值在5～9之间时,溶液缔合行为随pH值增大减弱幅度变小;pH值大于9时,溶液缔合行为随pH值增大逐渐增强。     

基于动态光散射的溶菌酶水力学直径研究

采用Zeta电位和粒度分析仪测量了溶菌酶的水力学直径,研究了pH值、离子强度和脲浓度对其大小的影响.随着 pH值增加,溶菌酶的水力学直径呈” W”形分布;在极端的碱性条件下,溶菌酶水力学直径随离子强度的增加而显著变大;中性pH值时,水力学直径随离子强度的增加变化不大.脲对溶菌酶具有双重作用,随着溶液中脲浓度的增加,溶菌酶的水力学直径先减小后增大.结果表明,动态光散射技术可以很好地应用于研究蛋白质分子的均一性和稳定性,同时也可以通过水力学直径来表征pH值、离子强度和脲对溶菌酶的影响.     

猪皮胶原蛋白的提取及粘度特性研究

以猪皮为原料,在柠檬酸和胃蛋白酶协同作用下提取胶原蛋白。采用旋转流变仪系统考察了浓度、pH、剪切速率、NaCl和CaCl2、乙醇和丙三醇对胶原蛋白粘度的影响。结果显示,胶原蛋白溶液粘度随浓度增大呈指数增加趋势;pH=3时粘度最大,pH=4和pH=6-9时粘度下降,pH=10时粘度又陡然回升;粘度随剪切速率的增大呈对数下降趋势;NaCl和CaCl2的添加都会使胶原蛋白溶液粘度下降;乙醇和丙三醇添加量在小于10％时,其添加浓度与粘度成正比例关系。通过对胶原蛋白粘度特性的研究,为制备新型胶原基医用粘合剂提供了理论基础。     

辉光放电电解降解水体中阳离子桃红FG的机理

用辉光放电电解（GDE）技术对模拟染料废水阳离子桃红FG的降解过程进行了研究。通过发射光谱法测定了GDE产生的活性粒子,用紫外光谱和总有机碳（TOC）分析仪研究了不同放电时间下的脱色率和去除率,用电导率仪和酸度计测定了降解过程中溶液的电导率和pH的变化,同时用离子色谱对降解中间产物进行了分析。结合各种分析结果,探讨了GDE降解阳离子桃红FG的机理。结果表明,在最佳电压600 V时,溶液中产生HO·、O·、H·等高活性粒子;放电120 min时,200 ml 20 mg/L阳离子桃红FG的脱色率和TOC去除率分别可达99.0%和72.6%;降解液pH先减小后增大,电导率存在先增大后减小的趋势;离子色谱测试表明,降解过程中产生多种有机小分子酸。羟基自由基（HO·）对阳离子桃红FG的降解起关键作用,GDE降解阳离子桃红FG的机理为：HO·作用下助色基团键断裂,产生酚类等中间产物,然后继续被降解为醌和小分子有机酸,最终矿化为Cl^-、NO₃^-、CO₂和H₂O。     

Synergistic Interactions of Cannabidiol with Chemotherapeutic Drugs in MCF7 Cells: Mode of Interaction and Proteomics Analysis of Mechanisms

Cannabidiol (CBD), a nonpsychoactive phytocannabinoid, has recently emerged as a potential cytotoxic agent in addition to its ameliorative activity in chemotherapy-associated side effects. In this work, the potential interactions of CBD with docetaxel (DOC), doxorubicin (DOX), paclitaxel (PTX), vinorelbine (VIN), and 7-ethyl-10-hydroxycamptothecin (SN−38) were explored in MCF7 breast adenocarcinoma cells using different synergy quantification models. The apoptotic profiles of MCF7 cells after the treatments were assessed via flow cytometry. The molecular mechanisms of CBD and the most promising combinations were investigated via label-free quantification proteomics. A strong synergy was observed across all synergy models at different molar ratios of CBD in combination with SN−38 and VIN. Intriguingly, synergy was observed for CBD with all chemotherapeutic drugs at a molar ratio of 636:1 in almost all synergy models. However, discording synergy trends warranted the validation of the selected combinations against different models. Enhanced apoptosis was observed for all synergistic CBD combinations compared to monotherapies or negative controls. A shotgun proteomics study highlighted 121 dysregulated proteins in CBD-treated MCF7 cells compared to the negative controls. We reported the inhibition of topoisomerase II β and α, cullin 1, V-type proton ATPase, and CDK-6 in CBD-treated MCF7 cells for the first time as additional cytotoxic mechanisms of CBD, alongside sabotaged energy production and reduced mitochondrial translation. We observed 91 significantly dysregulated proteins in MCF7 cells treated with the synergistic combination of CBD with SN−38 (CSN−38), compared to the monotherapies. Regulation of telomerase, cell cycle, topoisomerase I, EGFR1, protein metabolism, TP53 regulation of DNA repair, death receptor signalling, and RHO GTPase signalling pathways contributed to the proteome-wide synergistic molecular mechanisms of CSN−38. In conclusion, we identified significant synergistic interactions between CBD and the five important chemotherapeutic drugs and the key molecular pathways of CBD and its synergistic combination with SN−38 in MCF7 cells. Further in vivo and clinical studies are warranted to evaluate the implementation of CBD-based synergistic adjuvant therapies for breast cancer.     

Interphases in the Adhesive Bonding of Fluoropolymers

Strong and durable adhesive bonds may be made between polytetrafluoroethylene (PTFE) and either cyanoacrylate (CA) or epoxy adhesives, if the PTFE surface is modified by the use of a “primer” such as triphenylphosphine (TPP) or diaminodiphenylmethane (DDM). The primer mixes with the PTFE surface, and the modified surface is then capable of forming an interphase, tens to hundreds of nanometers thick, where interpenetration of the adhesive and adherend occurs. Using CA adhesives, PTFE/CA/PTFE block compression shear bond strength (ASTM D4501-85) of over 10 MPa can be achieved, with failure occurring cohesively. Initial work with epoxy adhesives indicates that the use of DDM primer gives adhesive bonds comparable in strength with those produced by modification of the fluoropolymer surface by sodium naphthalenide.     

The Influence of Glow and Afterglow Cold Plasma Treatment on Biochemistry,Morphology, and Physiology of Wheat Seeds

Cold plasma (CP) technology is a technique used to change chemical and morphological characteristics of the surface of various materials. It is a newly emerging technology in agriculture used for seed treatment with the potential of improving seed germination and yield of crops. Wheat seeds were treated with glow (direct) or afterglow (indirect) low-pressure radio-frequency oxygen plasma. Chemical characteristics of the seed surface were evaluated by XPS and FTIR analysis, changes in the morphology of the seed pericarp were analysed by SEM and AFM, and physiological characteristics of the seedlings were determined by germination tests, growth studies, and the evaluation of α-amylase activity. Changes in seed wettability were also studied, mainly in correlation with functionalization of the seed surface and oxidation of lipid molecules. Only prolonged direct CP treatment resulted in altered morphology of the seed pericarp and increased its roughness. The degree of functionalization is more evident in direct compared to indirect CP treatment. CP treatment slowed the germination of seedlings, decreased the activity of α-amylase in seeds after imbibition, and affected the root system of seedlings.     

正反向同时引发ATRP制备凹凸棒土/聚苯乙烯杂化粒子

通过脱醇法在凹凸棒土（ATP）表面接枝γ-氨丙基三乙氧基硅烷（APTES）实现氨基化（ATP-APTES）,再经酰胺化反应接枝α-溴代异丁酰溴,从而在ATP表面固载ATRP引发基团（ATP-Br）;最后以2,2-偶氮二异丁腈（AIBN）和ATP-Br为双组分引发体系进行正反向同时引发原子转移自由基聚合（SR&NI ATRP）制备ATP接枝聚苯乙烯杂化粒子（ATP@PS）。结果表明AIBN结合ATP-Br引发体系进行SR&NI ATRP具有活性/可控聚合的特征,随催化剂用量增大,体系过早偏离一级动力学行为。聚合温度在80℃,投料比为单体/催化剂/AIBN/ATP-Br=200/0.3/0.05/0.5的条件下,接枝聚合物和游离聚合物分子量差异随转化率（c）增大逐渐增加,转化率为31.1%时,两者分子量分布（PDI）均保持在1.54以下,ATP-Br表面ATRP引发基团的引发效率为6.3%。杂化粒子在PS基体中分散得到明显改善。     

Effects of Two Distinct Psychoactive Microbes,Lacticaseibacillus rhamnosus JB-1 and Limosilactobacillus reuteri 6475, on Circulating and Hippocampal mRNA in Male Mice

Discovery of the microbiota-gut–brain axis has led to proposed microbe-based therapeutic strategies in mental health, including the use of mood-altering bacterial species, termed psychobiotics. However, we still have limited understanding of the key signaling pathways engaged by specific organisms in modulating brain function, and evidence suggests that bacteria with broadly similar neuroactive and immunomodulatory actions can drive different behavioral outcomes. We sought to identify pathways distinguishing two psychoactive bacterial strains that seemingly engage similar gut–brain signaling pathways but have distinct effects on behaviour. We used RNAseq to identify mRNAs differentially expressed in the blood and hippocampus of mice following Lacticaseibacillus rhamnosus JB-1, and Limosilactobacillus reuteri 6475 treatment and performed Gene Set Enrichment Analysis (GSEA) to identify enrichment in pathway activity. L. rhamnosus, but not L. reuteri treatment altered several pathways in the blood and hippocampus, and the rhamnosus could be clearly distinguished based on mRNA profile. In particular, L. rhamnosus treatment modulated the activity of interferon signaling, JAK/STAT, and TNF-alpha via NF-KB pathways. Our results highlight that psychobiotics can induce complex changes in host gene expression, andin understanding these changes, we may help fine-tune selection of psychobiotics for treating mood disorders.     

Effects of Three Different Doses of Inter-Alpha Inhibitor Proteins on Severe Hypoxia–Ischemia-Related Brain Injury in Neonatal Rats

Hypoxia–ischemia (HI)-related brain injury is an important cause of morbidity and long-standing disability in newborns. We have previously shown that human plasma-derived inter-alpha inhibitor proteins (hIAIPs) attenuate HI-related brain injury in neonatal rats. The optimal dose of hIAIPs for their neuroprotective effects and improvement in behavioral outcomes remains to be determined. We examined the efficacy of 30, 60, or 90 mg/kg of hIAIPs administered to neonatal rats after exposure to HI for 2 h. Postnatal day 7 (P7) Wistar rats were exposed to either sham-surgery or unilateral HI (right carotid artery ligation, 2 h of 8% O₂) brain injury. A placebo, 30, 60, or 90 mg/kg of hIAIPs were injected intraperitoneally at 0, 24 and 48 h after HI (n = 9–10/sex). We carried out the following behavioral analyses: P8 (righting reflex), P9 (negative geotaxis) and P10 (open-field task). Rats were humanely killed on P10 and their brains were stained with cresyl violet. Male extension/contraction responses and female righting reflex times were higher in the HI placebo groups than the sham groups. Female open-field exploration was lower in the HI placebo group than the sham group. hIAIPs attenuated these behavioral deficits. However, the magnitude of the responses did not vary by hIAIP dose. hIAIPs reduced male brain infarct volumes in a manner that correlated with improved behavioral outcomes. Increasing the hIAIP dose from 30 to 90 mg/kg did not further accentuate the hIAIP-related decreases in infarct volumes. We conclude that larger doses of hIAIPs did not provide additional benefits over the 30 mg/kg dose for behavior tasks or reductions in infarct volumes in neonatal rats after exposure to severe HI.     

苯酚/丙酮市场供需现状与展望

分析了世界和我国苯酚／丙酮供需现状及消费结构,对未来供需进行了预测,提出了发展我国苯酚／丙酮装置的具体建议。     

小胶质细胞对阿尔兹海默病发生发展的影响作用

阿尔兹海默病(老年性痴呆,AD)是由β淀粉样蛋白(Aβ)和微管相关蛋白(Tau)聚集形成的具有毒性作用的寡聚物而引起的老年人主要以记忆力下降和脑部形成老年斑、神经纤维缠绕为特征的神经退行性疾病. 小胶质细胞作为中枢神经系统中的固有免疫细胞,是脑内免疫监视的关键成分,发挥内源性免疫防御作用. 正常生理状态的小胶质细胞能有效吞噬和清除毒性Aβ寡聚体,阻止AD发生. 在AD病理过程中,过度激活的小胶质细胞通过补体依赖途径过度吞噬突触,导致突触丧失,同时大量释放炎症因子,促进Tau相关病理变化,对神经元造成直接损伤,导致认知功能下降. 由此可见,小胶质细胞在AD发生发展过程中起着双刃剑的作用,探明小胶质细胞的极化状态及其在AD疾病机理中的作用将为攻克AD的药物研发提供突破性思路.