胆固醇液晶热致变色微胶囊的制备及其性能

为探索胆固醇类液晶在热致变色纺织品制备中的应用,采用三羟甲基三聚氰胺为壁材,胆固醇油醇碳酸酯和胆固醇壬酸酯的混合物为芯材,利用原位聚合法制备了胆固醇液晶微胶囊。对制备得到液晶微胶囊的微观形貌特征、热学性能以及热致变色性能进行了测试。测试结果表明：在乳化速度为6 000r/min、芯壁质量比为3：2、微胶囊包覆时反应溶液pH值为4.0的条件下,制备的液晶微胶囊粒径分布在10μm左右,微胶囊具有致密的壳结构、表面光滑的球形形态,以及良好的热致变色性能;它可在34.4 ～38.0 ℃的温度区间内,依次显示红黄绿蓝紫的颜色变化;其变色温度与人体体温接近,适合用于热致变色织物的制备。     

Beneficial effects of probiotic cholesterol-lowering strain of Enterococcus faecium WEFA23 from infants on diet-induced metabolic syndrome in rats

The aim of this study was to select probiotic Enterococcus strains that have the potential to improve metabolic syndrome (MS). Ten Enterococcus strains isolated from healthy infants were evaluated for their probiotic properties in vitro, and Enterococcus faecium WEFA23 was selected due to its cholesterol removal ability (1.89 ± 0.07 mg/10¹⁰ cfu), highest glycodeoxycholic acid-hydrolase activity (1.86 ± 0.01 U/mg), and strong adhesion capacity to Caco-2 cells (17.90 ± 0.19%). The safety of E. faecium WEFA23 was verified by acute oral administration in mice, and it was found to have no adverse effects on general health status, bacterial translocation, and gut mucosal histology. Moreover, the bene?cial effects of E. faecium WEFA23 on high-fat diet-induced MS in rats were investigated, and we found WEFA23 signi?cantly decreased body weight, serum lipid levels (total cholesterol, triacylglycerols, and low-density lipoprotein cholesterol), blood glucose level, and insulin resistance in rats fed with a high-fat diet. This indicated that administration of E. faecium WEFA23 improved almost all key markers of MS, including obesity, hyperlipidemia, hyperglycemia, and insulin resistance. Our results supported E. faecium WEFA23 as a candidate for cholesterol-lowering dairy products and improvement of MS. Our research provided novel insights on Enterococcus as a strategy to combat MS.     

Dietary Tuna Dark Muscle Protein Attenuates Hepatic Steatosis and Increases Serum High‐Density Lipoprotein Cholesterol in Obese Type‐2 Diabetic/Obese KK‐Ay Mice

Tuna muscle consists of light and dark muscle in approximately equal proportions. However, besides for the light muscle of tuna, cod, sardine, and salmon, few researches have assessed the health‐promoting functions of fish protein. Therefore, we evaluated the mechanisms underlying the alteration of lipid storage and cholesterol metabolism following the intake of tuna dark muscle protein (TDMP) by obese type‐2 diabetic/obese mice. Four‐week‐old male KK‐A^y mice were separated into 2 dietary groups, with one group receiving a casein‐based diet and the other receiving a diet with the substitution of part of the protein (50%, w/w) by TDMP (TDMP diet) for 4 wk. The TDMP diet significantly increased the content of serum high‐density lipoprotein cholesterol, partly due to the reduction of the expression of scavenger receptor class B member 1 in epididymal white adipose tissue. In addition, dietary TDMP decreased the content of hepatic triacylglycerol, which could be due to the enhancement of carnitine palmitoyltransferase‐2 activity through the activation of the expression of the peroxisome proliferative activated receptor‐α in the liver. These results suggest that TDMP could have the potential to prevent the development of obesity‐related diseases by suppressing the storage of hepatic triacylglycerol and cholesterol.     

家庭烹调对鲟鱼中脂肪酸和胆固醇的影响

对杂交鲟鱼（Acipenser baerii×A. schrenckii）进行了清蒸、油煎、微波、微波烤、烤箱烤和压力锅煎6 种家庭烹调处理,测定其脂肪和胆固醇含量、脂肪氧化指标和各脂肪酸含量的变化。结果表明,所有烹调方法均降低了n-3/n-6多不饱和脂肪酸含量的比值,其中压力烹调比值最高（0.85）,清蒸次之（0.83）,而烤箱烤最低（0.73）。胆固醇保存率以清蒸和压力锅煎最高,两种处理间无显著差异。烹调后样品酸价和硫代巴比妥酸值上升而过氧化值下降,并与样品的胆固醇含量相关。清蒸和压力烹调中脂肪酸和胆固醇变化相对较少,可能与其密闭烹调条件造成氧化程度较低有关。     

无斑鹞鲼蛋白质对大鼠胆固醇代谢的影响

目的：探讨无斑鹞鲼蛋白（Aetobatus flagelum protein,AFP）对高胆固醇模型大鼠胆固醇代谢的影响,并对其可能的作用机制加以研究。方法：5 周龄雄性Sprague-Dawley（SD）大鼠,适应性饲养1 周后,按体质量随机分为酪蛋白对照组、5% AFP组、10% AFP组,分别给予高胆固醇饲料及分别添加5%和10% AFP的高胆固醇饲料。28 d后测定大鼠血清总胆固醇（total cholesterol,TC）、高密度脂蛋白胆固醇（high density lipoprotein cholesterol,HDL-C）水平,肝脏TC、游离胆固醇水平,粪便中胆汁酸和中性固醇含量以及肝脏3-羟基-3-甲基戊二酸单酰辅酶A（3-hydroxy-3-methyl glutaryl coenzyme A reductase,HMG-CoA）、胆固醇酰基转移酶2（acyl coenzyme Acholesterolacyltransferase 2,ACAT2）、胆固醇7α-羟化酶1（cholesterol 7α-hydroxylase 1,CYP7A1）的mRNA表达量。结果：与酪蛋白对照组相比,无斑鹞鲼蛋白可显著降低大鼠血清和肝脏中的TC含量（P＜0.05）,明显增加血清HDL-C含量（P＜0.05）,极显著降低大鼠动脉粥样硬化指数（P＜0.01）。此外,无斑鹞鲼蛋白可明显增加大鼠粪便中胆汁酸和中性固醇的排出量（P＜0.05）,并可降低大鼠肝脏中ACAT2 mRNA的表达量（P＜0.05）,增加CYP7A1 mRNA的表达量（P＜0.05）,而对HMG-CoA mRNA的作用不显著。结论：无斑鹞鲼蛋白可明显降低大鼠血清和肝脏中的TC含量,降低大鼠血清动脉粥样硬化指数,其作用机制主要与增加肝脏内胆固醇的分解代谢以及促进粪便中性固醇和胆汁酸的排出有关。     

褐壳与绿壳鸡胚蛋特色营养物质的含量变化

根据比色法原理,采用酶标仪对2 个品种鸡胚蛋中的胆固醇、卵磷脂、VE含量进行测定。与0胚龄相比,胆固醇呈明显下降趋势,5～12胚龄降幅最大,12胚龄后保持稳定;卵磷脂含量无显著性变化;VE含量逐渐增加,到12胚龄均增加了4 倍,之后保持稳定。2 个品种相比,入孵前绿壳蛋中胆固醇含量为褐壳蛋的79.37%,极显著低于褐壳蛋（P＜0.01）;孵化至12胚龄后,2 个品种的胆固醇含量差异不显著（P＞0.05）;绿壳蛋中的VE无论是在入孵前还是在孵化后期均极显著高于褐壳蛋（P＜0.01）;绿壳鸡胚蛋中的卵磷脂含量与褐壳蛋相比差异不显著（P＞0.05）。总体看来,随着孵化日龄的增加,2 个品种鸡胚蛋中的同种营养成分的变化趋势一致;在12胚龄后胆固醇大大降低,VE含量显著增加,且卵磷脂含量丰富,具有更高的食用价值。     

北五味子总木脂素对C57BL/6小鼠高脂血症的影响

目的：探讨北五味子总木脂素（Schisandra Chinensis lignans,SCL）对高脂饮食诱导的高脂血症小鼠血脂调节的影响。方法：雄性C57BL/6小鼠60 只,随机抽取30 只设为正常对照组（CON）和正常＋SCL 组（CON＋SCL 100 mg/kg）,每组15 只,以普通饲料喂养。其余30 只小鼠以高脂饲料喂养4 周,确定高脂血症小鼠模型建立成功后,将小鼠随机分为模型组和SCL治疗组（模型＋SCL 100 mg/kg）,全部小鼠连续灌胃给药12周后检测血清中总胆固醇（total cholesterol,TC）、甘油三酯（triglyceride,TG）、低密度脂蛋白胆固醇（lowdensity lipoprotein cholesterol,LDL-C）和高密度脂蛋白胆固醇（high density lipoprotein cholesterol,HDL-C）含量并计算动脉粥样硬化指数（atherosclerosis index,AI）,检测小鼠脂/体比,检测肝组织中TC和TG含量。结果：与正常对照组比较,模型组小鼠血清中TC、TG、LDL-C、AI及脂/体比均显著增高（P＜0.01）,HDL-C含量降低,肝组织中TG和TC含量升高,与模型组比较,SCL 显著降低了小鼠血清TC、TG、LDL-C、AI及脂/体比（P＜0.01或P＜0.05）,升高了HDL-C含量,并降低了肝组织中TC和TG含量（P＜0.01）。结论：SCL 可以减轻高脂血症小鼠脂肪含量,对小鼠高脂血症具有一定的治疗作用。     

鱼油精制过程中的品质变化规律及评价

在传统的鱼油生产中,毛油经脱胶、脱酸、脱色、脱臭等工艺可以得到品质合格的精制鱼油,但传统鱼油生产对胆固醇、胆酸、反式脂肪酸等关乎人体健康的成分关注较少。本文通过模拟传统的鱼油生产工艺,在确保成品鱼油品质合格的同时,对鱼油中DHA、EPA、胆固醇、总胆酸、反式脂肪酸(C18:1tran,C18:2trans,C18:3trans)等进行了分析。结果表明,成品鱼油的酸值(AV)、过氧化值(POV)、碘值(IV)分别为0.53 mg KOH/g,4.35 mmol/kg和139.60 g/100 g,均达到了多烯鱼油行业一级标准(SC/T 3502-2000)。精炼工艺对DHA和EPA的影响不大,DHA和EPA的相对总含量为26%左右。成品油中胆固醇和总胆酸含量随着精炼的进行呈下降趋势,成品油中含量分别为2399 mg/kg和30 mg/kg,脱除率分别为57.4%和97.2%。反式脂肪酸含量随着精炼的进行呈上升趋势,成品油中总反式脂肪酸的相对含量为1.42%。以上结果表明,传统的鱼油精炼工艺尚存在一定的缺陷,需及时改善工艺,进一步提高鱼油的品质。