α-硫辛酸的研究进展

α-硫辛酸是一种具有很强抗氧化活性的含硫抗氧化剂.对α-硫辛酸在糖尿病及并发症、缺血再灌注损伤及辐射损伤等方面的最新实验研究、应用及其作用机制进行详细论述,说明α-硫辛酸是一种具有研究价值的用途广泛的抗氧化剂.     

α-硫辛酸对育肥猪脂肪代谢的影响

研究日粮中添加α-硫辛酸对肥育猪脂肪代谢的影响.对照组饲喂基础日粮,试验组在基础日粮中分别添加300、600和900 mg/kg的α-硫辛酸,试验期28 d.结果表明:Ⅱ-硫辛酸添加组血清中总胆固醇和甘油三酯均显著低于对照组,对低密度脂蛋白含量及高密度脂蛋白、肝脂酶活性均无显著影响.血清脂肪酶和脂蛋白脂酶活性随着α-硫辛酸添加水平的提高而增加,其中添加600、900 mg/kg α-硫辛酸组的脂肪酶活性与对照组相比提高显著,900mg/kg组的脂蛋白脂酶活性与对照组差异达到显著水平.α-硫辛酸的适宜添加水平为600～900 mg/kg.     

Scavenging ability on ROS of alpha-lipoic acid (ALA)

The scavenging ability of alpha-lipoic acid (ALA) towards superoxide anions, hydroxyl radicals and hydrogen peroxide was evaluated by means of chemiluminescence (CL). In neutral or acid conditions, ALA could scavenge superoxide anions and its scavenging efficiency depended on its concentration. In neutral or alkaline conditions, the CL intensity of the reaction of ALA with hydroxyl radical (OH radicals) decreased after the first 10 min and then increased with time, suggesting that ALA could scavenge OH radicals at the beginning, but yielded unknown intermediate products that could lead to the increase of CL intensity at later stages. The increase of CL intensity in the reaction of hydrogen peroxide with ALA may also be due to these products.     

α-硫辛酸对育肥猪生产性能和抗氧化功能的影响

研究日粮中添加α-硫辛酸对肥育猪生产性能和抗氧化功能的影响.对照组饲喂基础日粮,试验组在基础日粮中分别添加300、600和900 mg/kg的旷硫辛酸,试验期28 d.结果表明:与对照组相比,添加600、900 mg/kgα-硫辛酸降低了平均日增重(P＜0.05)和平均日采食量(P＜0.01),而各组料重比差异均不显著(P＞0.05);900mg/kgα-硫辛酸组总抗氧化能力增加显著(P＜0.05),谷胱甘肽过氧化物酶活性极显著增强(P＜0.01).α-硫辛酸添加组血清中丙二醛含量均显著降低(P＜0.05).α-硫辛酸的适宜添加水平为600 mg/kg.     

黑曲霉B0201产单宁酶生物转化没食子酸工艺研究

该文对微生物产单宁酶发酵五倍子合成没食子酸进行了研究.并对五倍子诱导黑曲霉产生单宁酶进行了生物转化实验研究,开展了产酶条件优化实验,对酶反应转化的最适pH值、温度、反应时间、底物浓度等进行研究,得出了最佳培养条件和微生物酶法制备没食子酸的工艺,为开发五倍子的生物化工加工技术提供参考.     

Optimization of process parameters in oriented strand board manufacturing with artificial neural network analysis

In the present work, an artificial neural network (ANN) model was developed for predicting the effects of some production factors such as adhesive ratio, press pressure and time, and wood density and moisture content on some physical properties of oriented strand board (OSB) such as moisture absorption, thickness swelling and thermal conductivity. The MATLAB Neural Network Toolbox was used for the training and optimization of the artificial neural network. The ANN model having the best prediction performance was determined by means of statistical and graphical comparisons. The results show that the prediction model is a useful, reliable and quite effective tool for predicting some physical properties of the OSB produced under different manufacturing conditions. Thus, this study has presented a novel and alternative approach to the literature to optimize process parameters in OSB manufacturing process.     

红枣干酪加工工艺研究

红枣干酪是在原料乳中添加枣泥制成的,符合中国人口味的风味干酪。对影响红枣干酪凝乳效果的主要因素进行了研究,试验结果表明:添加4%的枣泥,原料乳浓度越大,凝乳效果越好,用巴氏杀菌或高温短时杀菌,调节酸度到24°T,添加0.04%的CaCl2,凝乳效果较好。     

Innovative lay-up system in plywood manufacturing process

In the traditional plywood manufacturing process, the lay-up stage absorbs approximately 24% of the total manufacturing costs. It usually requires a large amount of manpower and produces a significant amount of waste material. Therefore, the authors have developed an innovative system based on a new idea that reduces these values drastically. The solution is characterized by intensive use of flexible automation, and this breakthrough lay-up system technology is specifically discussed in relation to plywood manufacture. Since the new system was tested, it has been adopted and used by the European leader in poplar plywood manufacturing. Interesting results include productivity increases of up to 20%, a decrease in lay-up costs of approximately 19% and a consumption of area reduced about 42%. Moreover, by reducing manpower requirements, the new system generates a significant reduction in the number of problems relating to product quality and operator safety, which is certainly not a trivial question in the traditional lay-up system.     

多功能聚合物纺丝设备的结构和功能研究

为了使新开发的工艺快速有效地从实验室投入生产,必须对现行的设备元件进行开发,使其能适应参数范围更广。就熔体纺丝而言,参数涉及挤压机、喷丝头、骤冷、上油、牵伸、空气喷射混合和卷绕设备。英国Fibre Extrusion Technology(FET)公司将这种用于热塑性和其他熔纺纤维的多功能纺丝机安装在德国图林根纺织塑料研究院(TITK),目的是为了支持该研究院的战略研究领域,特别是聚合物的结构与功能领域。     

Controlled release of alpha-lipoic acid through incorporation into natural polysaccharide-based gel beads

Alpha-lipoic acid (ALA) is an essential cofactor for mitochondrial multi-enzyme complexes related to energy production. However, it is unstable under light and heat and its biological half-life (t_1/2) is short. In this study, ALA was incorporated into alginic acid (Alg) gel beads to achieve stabilisation and sustained release. The cationic polymer chitosan (CS) was also added to the Alg gel beads to better control ALA release. In artificial gastric juice (pH 1.2), ALA release from the Alg gel beads was controlled through simple diffusion from the gel matrix. However, in artificial intestinal juice (pH 6.8), the Alg gel beads were immediately disintegrated. On the other hand, Alg gel beads with CS were not disintegrated in artificial intestinal juice (pH 6.8), and achieved pH-independent sustained release of ALA through an electrostatic interaction between the carboxyl groups of Alg and the amino groups of CS. ALA contained within the Alg gel beads was protected from light (UV) and heat (65 °C) compared with ALA alone. Addition of CS to the Alg gel beads further increased the stability of ALA. Thus, stabilisation and controlled release of ALA was achieved through incorporation of ALA in Alg gel beads containing CS.     

山桐子油提取工艺的研究及脂肪酸组成分析

以干燥的山桐子粉为原料,考察了不同提取剂及提取温度、料液比和提取时间对出油率的影响。通过单因素和正交试验得出最佳提取工艺条件为:乙醚-无水乙醇混合液(4:1,v/v)为提取剂、提取温度50℃、料液比为1:20、提取时间4.5 h,在此条件下山桐子的出油率为28.5%。然后将山桐子油脂肪酸组成与其他油脂进行比较,结果显示山桐子油亚油酸含量明显高于茶籽油、花生油和橄榄油。     

Production and structural analysis of triacylglycerols containing capric acid and conjugated linoleic acid isomers obtained by enzymatic acidolysis

BACKGROUND: Structured lipids containing medium‐chain fatty acids have interesting applications as reduced‐calorie fats; moreover, conjugated linoleic acid (CLA) isomers have shown interesting biological properties. The aim of this study was to synthesize triacylglycerols (TAGs) containing capric acid in the sn‐1‐ and sn‐3‐ positions and CLA isomers in the sn‐2‐ position, using different commercial available lipases. RESULTS: The homogeneous CLA‐TAGs (Tri‐CLA) were chemically synthesized starting from glycerol and CLA isomers, 9‐cis,11‐trans and 10‐trans,12‐cis CLA. The acidolysis reactions of Tri‐CLA with capric acid were carried out at 55 °C for different times in hexane; after 96 h the acidolysis average yield was 65%. The best capric acid incorporation in total TAGs was obtained after 96 h with Lipozyme IM (56.6%). The results of structural analysis carried out on the obtained TAGs showed that both Novozyme 435 and anhydrous Lipozyme IM gave the best incorporation of capric acid in sn‐1(3)‐ positions (61.8%). However, anhydrous Lipozyme IM gave also the highest CLA percent content in sn‐2‐ position (73.2%). CONCLUSION: Anhydrous Lipozyme IM appears to be the more effective enzyme in acidolysis reactions to obtain structured TAGs containing CLA isomers in the central position and capric acid at external positions. Copyright © 2009 Society of Chemical Industry     

牛骨胶原蛋白酶解工艺优化及结构特性分析

为研究前期纯化的特异性降解牛骨胶原蛋白的胶原蛋白酶(BSC)对牛骨胶原蛋白的酶解工艺,以水解度为响应值,在单因素试验基础上通过五元二次正交旋转组合试验,确定最佳酶解工艺为:反应温度46℃、牛骨胶原蛋白添加量5.14g/100mL、BSC添加量0.42g/100 mL、反应时间6h、pH 6.5,该工艺条件下水解度为34.98%。采用紫外光谱(UV)、荧光光谱(FS)、傅里叶红外光谱(FT-IR)、扫描电镜(SEM)对牛骨胶原蛋白及其产物进行结构特性分析。通过UV分析表明BSC酶的降解作用破坏了牛骨胶原蛋白的三股螺旋结构,游离出大量的氨基酸;FS分析表明牛骨胶原蛋白分子表面C═O、CONH_2、COOH逐步增多,胶原蛋白肽中生色基团分布也随之发生变化;FT-IR分析可知牛骨胶原蛋白经降解后的胶原蛋白肽的肽链上—NH_2~+—排斥作用逐渐减弱,主要以β-转角为主;SEM表明酶破坏了牛骨胶原蛋白的表面分子结构,使其变得疏松。     

香蕉假茎纤维制取工艺探讨

分析了香蕉假茎纤维的化学成分,选择预酸二煮脱胶工艺进行香蕉假茎纤维的制取,并对制得的纤维性能进行了测试。     

浓缩西洋菜蜜饮料生产工艺流程的研究

西洋菜在香港是无人不晓的蔬菜，喝西洋菜饮料以消暑、避孕在香港已成为一种消费的新时尚。利用现有的耐高温灌装PET瓶生产线，通过小试和中试。新鲜西洋莱原料在经过适当地酸化处理后，采取UHT杀菌、高温灌装的生产工艺，一举生产出符合广州市企业产品执行标准和客户要求的浓缩西洋菜蜜饮料。该工艺的显著特点乏一是原料只能经过适当地酸化处理，之二是不能采用中温灌装。     

甜菜糖生产中的节能新技术和新工艺

介绍了反渗透膜技术和冷冻结晶技术在甜菜制糖中的应用,同时还介绍了一种将微滤膜清净,离子交换树脂软化,反渗透膜预浓缩稀汁和冷冻结晶与传统制糖工艺结合的节能环保型甜菜制糖新工艺.     

响应面法优化花生四烯酸微胶囊工艺的研究

采用辛烯基琥珀酸酯化淀粉HI-CAP100和麦芽糊精作为复合壁材,以花生四烯酸为芯材,通过喷雾干燥法制备微胶囊化花生四烯酸,以微胶囊化效率为响应值,用响应面分析法（RSA）对花生四烯酸微胶囊化工艺进行了优化,确定最优工艺参数为:固形物含量39%,均质压力37MPa、喷雾干燥进风温度191℃,出风温度为88℃。      

猫屎瓜籽油提取及脂肪酸组成分析

目的:研究猫屎瓜籽油（Decaisnea Insignis seed oil,DIO）溶剂法提取的最佳工艺,猫屎瓜籽油的理化性质、脂肪酸组成。方法:利用响应曲面法（response surface methodology,RSM）建立溶剂法萃取猫屎瓜籽油的数学模型,获得最佳萃取工艺;利用气相色谱-质谱法测定猫屎瓜籽油中脂肪酸组成及含量。结果:最佳工艺条件:提取温度77℃、提取时间8h、料液比（g/mL）1:20,此条件下提取率28.14%;猫屎瓜籽油中单不饱和脂肪酸相对含量75.44%,其中棕榈油酸相对含量59.75%、9-油酸相对含量14.81%、8-油酸相对含量0.88%。结论:溶剂法提取猫屎瓜籽油油脂品质好;猫屎瓜籽油中单不饱和脂肪酸尤其是棕榈油酸含量高,可作为棕榈油酸的新油源。      

鱼油精制过程中邻苯二甲酸酯类化合物分析及变化规律

建立了气相色谱-质谱法检测鱼油样品中的邻苯二甲酸酯类化合物(phthalate acid esters,PAEs)的方法,并研究PAEs在鱼油精炼过程中的变化规律。研究表明,16种PAEs标准物质在20min内实现有效分离,在0.05~1.0μg/m L浓度范围内呈现出良好的线性关系(R20.998 3),加标实验回收率为82.1%~107.4%,相对标准偏差(RSD)为0.8%~12.9%,检出限为0.08~0.30 mg/kg。同时,毛油中3种塑化剂(DIBP,DBP和DEHP)含量分别为0.06、0.05和0.04 mg/kg,且随着精炼工艺的进行呈上升趋势,成品油中的含量分别为0.19、0.24和0.06 mg/kg。精炼工艺中所使用的化学助剂是造成鱼油中3种塑化剂含量增加的主要因素。