超临界CO_2萃取去除蛋黄粉中胆固醇和甘油三酯的研究

采用超临界 CO2 萃取 ,对去除蛋黄粉中胆固醇和甘油三酯进行了研究 .市购鲜鸡蛋去壳、分别收集湿蛋白和蛋黄 ,在 4 5℃下分别真空干燥 ,得蛋白粉和蛋黄粉 .取蛋黄粉装入高压釜中 ,进行超临界 CO2 循环萃取 .通过正交试验得最佳工艺条件是 :A萃取压力为 31 .5MPa,B萃取温度 4 0℃ ,C被萃取蛋黄粉重 30 0 g,D萃取时间 3h.所得蛋黄粉中胆固醇和甘油三酯等中性脂的残留量质量分数仅为 0 .0 1 9% .与不含此类脂质的蛋白粉混合 ,制成几乎不含胆固醇和甘油三酯的高级绿色保健营养食品鸡蛋粉 .     

超临界CO2技术萃取蛋黄磷脂

采用新型物理分离技术──超临界CO₂萃取法,提取天然蛋黄粉中的磷脂.在40MPa,先去除蛋黄粉中甘油三酯和胆固醇,再萃取磷脂.结果显示,磷脂纯度为95%,N/P比值为1.003,λ_max=214nm,薄层层析显示磷脂着色点清晰,并去除了绝大部分甘油三酯和胆固醇.此法操作简单、产品质量高、安全和不污染环境,还可得到天然纯蛋黄油和蛋白.     

薄荷油超临界CO2萃取条件的优化和筛选

以样品中的薄荷脑含量为指标,通过单因素和正交实验对影响薄荷(Mentha haplocalyx Briq.)油超临界CO2萃取的因素进行研究,筛选出薄荷油超临界CO2萃取的最佳条件.研究结果表明,影响样品中薄荷脑萃取率的因素从大到小依次为萃取压力、萃取温度、萃取时间、CO2流量.样品中薄荷脑含量最高的超临界CO2萃取条件为萃取压力10 MPa、萃取温度50℃、CO2流量30 L·h-1且萃取时间1.5 h.     

螺旋藻有效成分超临界萃取与分离研究

使用超临界CO2萃取技术对钝顶螺旋藻粉进行萃取与分离,结果表明:超临界CO2萃取的最优条件为压力20Mpa,夹带剂使用量100mL/100g,温度50℃,萃取时间2h;利用凯氏定氮法及气相色谱法分别对超临界萃取处理过的螺旋藻中蛋白质和多糖进行研究与分析,结果表明:螺旋藻粉中蛋白质含量为49.39%,螺旋藻多糖中的单糖含量占多糖粗品的9.25%,主要组成为鼠李糖、木糖、甘露糖、葡萄糖、半乳糖等。     

正交实验优选八角茴香油的超/亚临界CO_2萃取工艺

通过L16(45)正交实验优选最佳的超临界CO2萃取工艺条件,并在此基础上通过二因素随机区组实验优选最佳的亚临界CO2萃取工艺条件,以八角茴香油的得油率作为考查指标,以各实验方案所得茴香油中反式茴香脑的相对含量作为茴香油质量的评价指标.实验结果表明:最佳的亚临界CO2萃取工艺条件为:萃取压力为7 MPa、萃取温度为22 ℃、解析压力Ⅰ为7 MPa、解析温度Ⅰ为30 ℃、解析压力Ⅱ为5 MPa、解析温度Ⅱ为25 ℃,萃取时间为2.0 h,在此条件下八角茴香油的得油率可达12%以上,茴香油中反式茴香脑的相对含量可达91.2178%.采用亚临界CO2萃取,即保持了超临界CO2萃取八角茴香油高品质和天然芳香的优点,又能显著降低设备投资和成产成本,更有利于在生产中推广.     

干姜超临界CO2萃取与水蒸气蒸馏工艺比较研究

目的：比较干姜的超临界CO2萃取与水蒸气蒸馏两种工艺的差别,为其在复方制剂中的应用提供工艺设计参考。方法：分别用超临界CO2萃取和水蒸气蒸馏处理干姜药材,采用GC、TLC对产物进行分析比较。结果：超临界CO2萃取产物得率为8．0％,水蒸气蒸馏得率为0．2％,GC、TLC显示超临界CO2萃取物比水蒸气蒸馏样品有较多的成分。结论：干姜的超临界CO2萃取工艺较水蒸汽蒸馏工艺的产物量高,成分较多。     

微孔草籽油的超临界CO2流体萃取及HPLC—MS分析

利用超临界CO2萃取微孔草籽油,并对籽油进行了HPLC／MS分析。实验确定的最佳超临界CO2流体萃取条件是：萃取温度45℃,萃取压力20MPa,CO2流量为35-40kg／h,萃取时间120min,在此条件下白刺籽油的萃取率为16．12％。利用HPLC／MS对微孔草籽油分析,发现其不饱和脂肪酸的相对含量高达73．19％。比较了超临界CO2萃取微孔草籽油油样和石油醚萃取微孔草籽油油样的理化性质,发现超临界CO2流体萃取的籽油质量优于传统溶剂萃取的籽油。     

超临界CO2萃取洋葱挥发油工艺研究

本实验采用超临界CO2萃取技术从冻干洋葱粉中萃取挥发油。以洋葱挥发油得率为考察指标,经单因素及正交试验,考察了萃取温度、萃取压力、CO2流量、萃取时间4个因素对超临界CO2流体萃取的影响。结果表明萃取压力20 MPa,萃取温度35℃,CO2流量为14 kg/h的条件下萃取2.5 h为最佳工艺,洋葱挥发油得率达0.53%。     

超临界CO2萃取百合花挥发油的工艺研究

本文介绍了超临界CO2萃取百合花中挥发油的提取分离工艺,重点研究了超临界CO2萃取压力、温度、时间对出油率的影响。正交试验结果表明：影响超临界CO2萃取的主要因素为C3〉A2〉B2（A为萃取压力,B为萃取温度,C为萃取时间）;最佳工艺参数：SC-CO2萃取压力为18MPa,温度为50℃,时间为90min,流量为25L／min,所得百合花挥发油的出油率高达2．92％。     

白果油的提取工艺及其化学成分研究

采用正交实验对超临界CO2萃取白果油的工艺条件进行优化,比较超声波提取、索氏提取、超临界CO2萃取3种方式对白果油提取率的大小,用最佳提取方式分析不同品种白果中油脂的含量,并用GC-MS分析其成分.结果表明: (1)3种提取方式对白果油提取率的大小顺序为:超临界CO2萃取(添加夹带剂)＞索氏提取＞超声波提取.(2)超临界CO2萃取白果油的最佳工艺条件为:温度40℃、压力20 MPa、流速15 L/h、时间3 h并添加石油醚夹带剂,不同品种白果干粉中油脂得率为3.6%～7.11%.(3)GC-MS分析表明:从超临界萃取白果油中鉴定出17种化学成分,其中不饱和脂肪酸占85.4%;超声波和索氏提取相似,分别从提取的白果油中鉴定出10种和9种化学成分,其中不饱和脂肪酸含量分别为90.3%和90.1%;不饱和脂肪酸以十六、十八碳的为主.     

Use of two freezing extenders to cool stallion spermatozoa to 5 degrees C with and without seminal plasma

Motion characteristics of cooled stallion spermatozoa in 2 freezing extenders were studied. Ejaculates from 8 stallions were split into treatments and cooled in thermoelectric cooling units at each of 2 rates. Cooling started at 37 degrees C for Experiments 1 and 3 and at 23 degrees C for Experiments 2 and 4, at a rate of -0.7 degrees C/min to 20 degrees C and from 20 to 5 degrees C, at either -0.05 degrees C/min (Rate I) or -0.5 degrees C/min (Rate II). Percentages of motile (MOT) and progressively motile spermatozoa (PMOT) were determined at 6, 24 and 48 h. Treatments in Experiment 1 were modified skim milk extender (SM); SM + 4% egg yolk (EY); SM + 4% glycerol (GL); and SM + 4% egg yolk + 4% glycerol (EY + GL). At 24 and 48 h, MOT and PMOT were lowest (P < 0.05) for spermatozoa extended in SM + EY; spermatozoa in SM + GL had the highest MOT and PMOT. Thus, glycerol partially protected spermatozoa against the effects of cooling after long-term storage. Treatments in Experiment 2 were SM, semen centrifuged and pellet resuspended in SM (SMc), SM + EY, and semen centrifuged and pellet resuspended in SM + EY (EYc). Spermatozoa in SM + EYc had the highest (P < 0.05) PMOT at 24 h and MOT and PMOT at 48 hours. Spermatozoa in SM + EY (not centrifuged) had the lowest MOT and PMOT at 24 and 48 h, respectively. There was a detrimental interaction between egg yolk and seminal plasma. Extenders in Experiment 3 were Colorado extender (CO3), CO3 + 4% egg yolk (EY), CO3 + 4% glycerol (GL), and CO3 + 4% egg yolk + 4% glycerol (EY + GL). Spermatozoa in CO3 + EY had the lowest (P < 0.05) PMOT at 24 and 48 h. CO3 did not protect spermatozoa cooled in the presence of seminal plasma. Therefore, in Experiment 4 we tested CO3 with seminal plasma present (control) and semen centrifuged and pellet resuspended in CO3 (CO3c), CO3 + EY (EYc), CO3 + GL (GLc) and CO3 + EY + GL (EY + GLc). Spermatozoa in CO3 had the lowest (P < 0.05) MOT and PMOT at all time periods, which suggested a detrimental interaction of this extender with seminal plasma.     

钴—60对高兔卵黄液中大肠杆菌的灭菌研究

用钴－60γ射线对接种于卵黄液中的大肠杆菌进行辐照灭菌,并测定了卵黄液的抗体效价、活性氧和卵黄液保存期的变化。结果表明：1.大肠杆菌在卵黄液中的D10值为0.31-0.37kGy,杀灭卵黄液中大肠杆菌的照射剂量为3kGy;2.辐照量在15kGy以下时,对卵黄液的抗体效价没有影响或仅有轻微影响;3.经8kGy照射后的卵黄液在常温、4℃、-10℃条件保存时,保存期明显长于未照射的卵黄液。     

制首乌醇提物及其主要成分大黄素对斑马鱼非酒精性脂肪肝的治疗作用

研究制首乌醇提物及其主要成分大黄素对斑马鱼非酒精性脂肪肝疾病(non-alcoholic fatty liver disease, NAFLD)的治疗作用。选取野生型斑马鱼若干,随机均分为对照组、模型组、制首乌醇提物(RPMP)组和大黄素(emodin)组,于胚胎受精后5天,对照组给于普通饲料AP100,模型组给予2 mg/mL蛋黄粉(EY powder),制首乌醇提物组分别给予2 mg/mL蛋黄粉与低剂量组(1 mg/mL)、中剂量组(1.5 mg/mL)、高剂量组(2 mg/mL),大黄素组分别给予2 mg/mL蛋黄粉与低剂量组(0.25μg/mL)、中剂量组(0.5μg/mL)、高剂量组(1μg/mL)。72 h后观察斑马鱼存活率和体重、体长、BMI的变化■,用整体油红染色评判脂肪肝发生率,石蜡切片观察肝组织病理形态,甘油三酯(TG)、总胆固醇(TC)试剂盒判断斑马鱼体脂含量。制首乌醇提物组与大黄素组能显著降低非酒精性脂肪肝斑马鱼的死亡率、BMI、TG含量,并显著改善斑马鱼幼鱼肝脏脂质沉积情况(P<0.05)。由此可见制首乌醇提物与大黄素可有效治疗斑马鱼NAFLD,且大黄素可能为制首乌治疗NAFLD的主要有效成分。     

Egg yolk improves lipid profile, lipid peroxidation and retinal abnormalities in a murine model of genetic hypercholesterolemia

Carotenoids are believed to inhibit oxidative stress. We investigated the protective effect of lutein and egg yolk supplementation on systemic and retinal alterations in apolipoprotein E-deficient (apoE-/-) mice, an experimental model of hypercholesterolemia and cardiovascular disease. Three-month-old wild-type and apoE-/- mice received one of the following: vehicle, lutein (0.09 mg/kg per day) or egg yolk (0.8 g/kg per day), by gastroesophageal cannula for 3 months. Total cholesterol (TC), triacylglycerol (TG) and lipid peroxidation (TBARS) were measured in plasma. TBARS levels were also determined in retinal homogenates. Ultrastructural morphology was analyzed by electron microscopy. ApoE-/- mice, with increased TC and TG concentrations, had higher systemic (P<.05) and retinal (P<.01) levels of lipid peroxidation than wild-type strains. Electron microscopy showed ultrastructural alterations (basal laminar deposits, open intercellular junctions, increased cytoplasmic vacuoles) in the retinas from apoE-/- mice. Egg yolk significantly reduced plasma TG (P<.05) and, without changes in TC, decreased plasma lipid peroxidation (P<.05). Lutein supplementation marginally affected the parameters. Less severe retinal ultrastructural alterations were observed in apoE-/- mice receiving either egg yolk or lutein. In the apoE-/- mouse model, egg yolk improved the lipid profile and reduced systemic lipid peroxidation (P<.05). While lutein and egg yolk did not seem to reduce retinal lipid peroxidation, a reduction in retinal ultrastructural alterations was observed.     

The domestic goat: a useful model to determine effects of diet and exercise on cholesterol accumulation in the body

1. Young goats were used to study factors contributing to atherosclerosis. 2. Cholesterol in egg yolk affected plasma cholesterol concentration more than did a similar amount of crystalline cholesterol in the diet. 3. Goats fed high fat diets developed fatty lesions in their aortas. 4. Cholesterol concentration in low-density lipoprotein was greatest in goats fed restricted-calorie diets without exercise, but least in goats fed liberally and exercised. 5. Cholesterol concentration in liver and fat deposition in aorta were greatest in the restricted-calorie, no exercise regime.     

奎宁的热解机理、动力学及贮存期研究

利用热重-红外联用技术测得奎宁在氮气气氛中的热分解曲线,协同使用Achar法和Coats-Redfern法两种方法同时进行动力学处理,根据热分解的表观活化能(E_a)和指前因子(A)计算推断奎宁的贮存期。奎宁晶体在219.93～389.93℃发生了第一步分解,先后释放了醇类、CO、CO_2、醚类、胺类等物质,反应机理为化学反应控制,对应的函数名称是反应级数方程,反应级数n=2;第二步分解(389.93～800℃)是由于残余分子骨架中苯并吡啶环的深度裂解碳化,过程较为缓慢,形成了CO_2、H_2O、NH_3等气体。经红外光谱解析和热重数据结合分析,晶体在第一步分解时又先后分为两个阶段,首先是苯并吡啶环上与两个氧原子相连的化学键断裂,其次是支链上的其它原子化学键相继发生断裂并裂解;根据第一步热分解的表观活化能(E_a)和指前因子(A)推断,在室温25℃下,奎宁的贮存期为4～5年。     

硅藻金色奥杜藻色素的HPLC分析与超临界CO2萃取研究

以硅藻金色奥杜藻(Odontella aurita)为实验材料,利用高效液相色谱法分析了其色素组成与含量,采取超临界CO2萃取技术研究了从干藻粉内提取岩藻黄素的条件。结果表明,该藻主要含有岩藻黄素、硅甲藻黄素、β-胡萝卜素、硅藻黄素等类胡萝卜素以及叶绿素a和叶绿素c1,其中岩藻黄素为该藻含量最高的类胡萝卜素。色素的萃取率与压强、温度、夹带剂含量以及萃取时间呈正相关,夹带剂含量对萃取率影响最大,CO2流速的影响最小;与有机溶剂法相比,超临界CO2萃取岩藻黄素效率略低,而更利于岩藻黄素的选择性萃取及分离提纯;岩藻黄素的SFE-CO2适宜条件为压强400 bar、温度50℃、CO2流速0.2 L/min、夹带剂比例10%、萃取时间2～3 h。     

Effects of cooling and freezing on pH of semen extender

The pH change of 10 different buffering systems with temperature ranging from room to 5 °C was examined; three were conventional buffers which included phosphate yolk, citrate yolk, and skim milk. Seven were Good's buffers with egg yolk which included TES, TRIS, BES, MOPS, PIPES, MES, and TEST. The pH of the three conventional buffers did not change with decreasing temperature, but Good's buffers showed an increase in pH with decreasing temperature from room to 5 °C. The pH change due to temperature was measured for TEST buffer solution with and without 20% egg yolk containing 2 or 6% of five different cryoprotective compounds. The pH at 5 °C was significantly higher than at room temperature. The addition of egg yolk and/or cryoprotective compound did not alter the pH significantly during cooling, even though a slight drop in pH was noted with the addition of egg yolk indicating that the change in pH is primarily due to the buffer. The pH of TEST yolk buffer (pH 7.2 at room temperature) was measured continuously from 37 °C to below freezing (?18 °C). The pH increased with decreasing temperature to 8.0 ± 0.2 from 37 to ?14 °C at which point it dropped abruptly to pH 6.5 ± 0.2.     

林蛙卵油的提取研究

利用林蛙卵提取林蛙卵油,并对影响林蛙卵油提取率的因素,如提取溶剂的选择、提取温度、提取时间及提取料液比等条件进行研究,通过正交试验确定获得最大林蛙卵油产率的条件。即:以石油醚(30~60)作为提取剂;提取温度65℃;提取时间为4 h;提取料液比为1:9。并对提制的林蛙卵粗油进行精制。得到具有透明黄色,鱼腥味道的林蛙卵油。     

超临界CO_2萃取当归挥发油及其在烟草中的应用研究

为开发新的天然烟用香料,研究了超临界CO2萃取当归挥发油的工艺,用GC/MS分析了挥发油中的挥发性和半挥发性成分,并用该挥发油进行了卷烟加香试验。结果表明:①超临界CO2萃取当归挥发油的优化工艺条件为:萃取温度40℃、萃取压力45Mpa、萃取时间1.5 h、CO2流量20 L.h-1,分离釜压力8 Mpa,分离釜温度45℃。②当归挥发油共鉴定出29种成分,主要有藁本内酯、丁烯基芙内酯、亚油酸、棕榈酸、油酸以及萜烯类化合物等。③卷烟加香评价结果表明,当归挥发油在丰富烟香、掩盖杂气、改善口感方面有较好的作用。