苯乙基间苯二酚纳米结构脂质载体制备及稳定性分析

目的解决苯乙基间苯二酚的不稳定性及水溶性差的问题。方法采用热高压均质法制备得到苯乙基间苯二酚纳米结构脂质载体(NLC),通过考察其平均粒径、zeta电位、光稳定性和长期储存稳定性等物理化学稳定性,阐明了苯乙基间苯二酚NLC的稳定性和水溶性。结果优化条件下制备的苯乙基间苯二酚NLC平均粒径为(500±35)nm,多分散性指数(PDI)为0.098,平均包封率和载药量分别为96.9%±0.3%和4.95%±0.03%。结论热高压均质法制备的苯乙基间苯二酚NLC具有良好的稳定性,可与去离子水以任意比例稀释,且所用载体NLC对药物有很高的包封率,保证了药物的有效利用度,可广泛用于化妆品配方。     

蛋白修饰植物甾醇脂质体的制备及体外消化研究

本研究以植物甾醇(PS)替代胆固醇与卵磷脂(PC)为原料,以粒径、多分散系数PdI、电位和包封率为指标,采用乙醇注入法制备蛋白修饰的植物甾醇脂质体(SPI-LS),通过单因素优化脂质体制备工艺,研究了SPI-LS的复溶性及其在水中的溶解度,并考察了植物甾醇包埋前后体外消化生物活性。结果表明,最佳制备工艺为:PS:PC为1:4,乙醇体积比为25%,蛋白含量为1%;脂质体复溶后外观与冻干前无显著差异,溶解度可达1.971 mg/mL;经3 h体外胃肠消化后,SPI-LS中植物甾醇的生物活性仍可保持在50%以上,是未经包埋植物甾醇的三倍之多。故优化制备条件得到的SPI-LS复溶性良好,并能有效保持植物甾醇的生物活性。     

壳聚糖修饰植物甾醇脂质体的制备及稳定性研究

采用乙醇注入法制备植物甾醇脂质体(Phytosterol Liposome,PLs),并以不同浓度壳聚糖进行修饰优化制备工艺;通过粒径、Pd I、电位和稳定性指数,分析评价了壳聚糖修饰植物甾醇脂质体(Chitosan modified Phytosterol Liposome,CS-PLs)在不同环境下的稳定性;并对壳聚糖修饰前后PLs进行了体外胃肠消化环境稳定性实验。结果表明:当壳聚糖浓度为0.3 mg/mL时可获得粒径小、分布均一的CS-PLs;且pH、温度和离子强度及种类均对CS-PLs稳定性有显著影响;PLs经壳聚糖修饰前后,胃消化稳定性均良好,但在模拟肠消化环境中,经壳聚糖修饰后的PLs表现出更好的稳定性。     

我国10种铁核桃油的组成特性和氧化稳定性

选取我国新疆、云南和西藏三大主要产区的10种代表性铁核桃样品,制备铁核桃油,测定了铁核桃油的脂肪酸组成,总酚、生育酚、植物甾醇含量及氧化稳定性,采用化学计量学的方法对铁核桃油的组成特性进行分析。结果表明:我国铁核桃油的脂肪酸主要为亚油酸(54.84%~66.97%),油酸(15.88%~26.04%),亚麻酸(6.82%~12.25%)和棕榈酸(5.12%~7.62%)。微量伴随物生育酚含量176.89~832.86 mg/kg、植物甾醇含量530.96~1 095.47 mg/kg、总酚含量1.42~15.84 mg/kg,氧化稳定性指数(OSI)为0.55~3.39 h。基于回归分析发现,影响铁核桃油氧化稳定性的主要组成物质是亚油酸、亚麻酸、γ-生育酚和总酚。     

响应面试验优化植物甾醇超声乳化工艺及其乳化稳定性

采用超声乳化法,以蔗糖酯为乳化剂,通过单因素试验和响应面分析,对植物甾醇超声乳化的工艺条件进行研究,结果表明：超声功率330 W、超声时间35 min、植物甾醇加入量0.53%、超声频率28 kHz、超声温度30 ℃、蔗糖酯质量分数6%条件下,植物甾醇乳化液吸光度为1.57,吸光度与理论预测值基本一致。对超声乳化法与水浴乳化法制备的植物甾醇乳化液的稳定性进行评价,并采用倒置显微镜观察植物甾醇乳化液的粒径大小及形态,结果表明：超声乳化法制备的植物甾醇乳化液稳定性更好,粒径较小且更均匀。     

豆渣蛋白-植物甾醇纳米颗粒的制备及其性质表征

植物甾醇（Phytosterol,PS）具有多种优秀的生理活性,但较低的水溶性和生物可及性一直阻碍其被广泛应用。该研究以豆渣蛋白（Okara protein,OP）为原料,利用反溶剂法结合高压微射流技术制备了豆渣蛋白-植物甾醇纳米颗粒,并对其性质进行了表征。研究结果表明：高压微射流处理可显著降低OP-PS颗粒的粒径,明显提高PS的包埋率。在120 MPa高压微射流循环处理3次后,OP-PS颗粒的粒径可达到139.28 nm,PS包埋率高达98.63%,水溶重分散性良好。对OP-PS颗粒进行稳定性评估,发现常温贮藏50 d后,甾醇包埋率仍能保持在66.90%左右,且热稳定性明显优于同等条件下制备的大豆分离蛋白-植物甾醇颗粒（SPI-PS）。可能的原因是,OP的游离巯基及二硫键明显高于SPI,高压微射流能诱导蛋白分子内或分子间二硫键的形成与交联,可以有效提高纳米颗粒的稳定性。高压微射流技术制备的OP-PS纳米颗粒具有较高的稳定性和甾醇荷载能力,能够为工业生产水溶性甾醇提供借鉴。     

影响核桃油包水乳液物理与氧化稳定性的因素分析

以核桃油为油相,以聚甘油聚蓖麻油酸酯(PGPR)为表面活性剂,制备油包水(W/O)乳液,乳液于55 ℃避光保存,每隔1 d测定乳液液滴的平均粒径及粒径分布等物理特性,同时检测乳液初级氧化产物—脂质氢过氧化物与次级氧化产物—己醛,探究水油界面与表明活性剂浓度对W/O乳液稳定性影响。结果表明,在W/O乳液,油水界面存在加速乳液脂质氧化,降低了乳液氧化稳定性。0.3～1.0% PGPR,表面活性剂浓度增大显著降低乳液液滴粒径,提高乳液物理稳定性;同时,表面活性剂浓度增加显著推迟了初级与次级产物形成延迟期,提升了乳液脂质氧化稳定性。W/O体系中过量表面活性剂与脂质氢过氧化物相互作用,增加了脂质氢过氧化物在油相的浓度,并降低了该初级氧化物的分解速率。     

番茄红素纳米结构脂质体的制备

对番茄红素纳米结构脂质体(lyco-NLC)的制备工艺进行了研究,以产品的平均粒径、多分散性系数(PDI)和包封率为指标,通过单因素实验和正交实验研究了物料因素和操作因素对lyco-NLC的影响,确定最佳制备工艺。并对lyco-NLC进行了形貌观察和贮藏稳定性研究。结果表明,lyco-NLC的最佳制备工艺条件为:总脂质质量浓度7.5 g/100 m L,固液脂质量比3.5∶1,表面活性剂吐温80质量浓度2 g/100 m L,均质压力50 MPa,均质次数3次。在最佳制备工艺条件下,lyco-NLC平均粒径为230 nm,PDI为0.23,包封率达到91.95%,产品中番茄红素载量高达4%,具有很好的水分散性。透射电子显微镜结果表明lyco-NLC粒子呈规则的球形,分散均匀。30 d的贮藏实验表明lyco-NLC具有良好的物理稳定性(平均粒径270 nm,PDI0.3)。     

植物甾烷醇酯粉体制备工艺的响应面优化

为研究植物甾烷醇酯的粉体制备工艺，满足药品及功能食品的开发，通过单因素试验考察料水比、二氧化硅比例、酪蛋白酸钠比例、麦芽糊精比例和进风温度这5个因素对植物甾烷醇酯的粉体制备效果的影响，并通过Plackett-Burman试验考察影响因素的显著性，最后通过Box-Behnken试验对3个显著因素进行响应面优化分析。优化后的喷粉工艺最佳条件为：料水比51.30%，二氧化硅比例4.05%，麦芽糊精比例15.02%。在该条件下制备植物甾烷醇酯粉末，粉末得率为87.04%、粉末中甾醇含量为64.12%，与模型预测值（粉末得率87.281%，粉末中甾醇含量64.1525%）吻合度较高。所制成的植物甾烷醇酯粉末得率及甾醇含量较高，可用于功能食品或药品。     

均质和杀菌条件对核桃油微胶囊化的影响及贮藏稳定性

为研究不同均质及杀菌条件下乳化液特性与微胶囊包埋率、表面油质量分数之间的相关性,通过LUMiSizer 611分散体分析仪探究不同条件下乳化液稳定性、粒径大小和粒径分布规律对微胶囊包埋率的影响,并对最优条件下的微胶囊形貌和贮藏稳定性进行分析。结果表明,在均质压力40 MPa、均质温度65℃和杀菌条件为85℃/15 min时乳化液不稳定性指数和平均粒径最小,粒径分布离散度总体呈下降趋势,此时包埋率分别为95.38%、97.12%和94.23%;在上述最适工艺条件下核桃油微胶囊平均粒径为6.62μm,表面油质量分数为1.03%,微胶囊化包埋率为96.41%,在扫描电镜下观察微胶囊表面和内部结构良好,具有良好的包埋效果。加速贮藏实验表明,与未包埋的核桃油相比,核桃油微胶囊具有良好的氧化稳定性;在不同条件下经过35 d贮藏,其保留率下降幅度有所不同,将微胶囊于低温、避光、无氧或氧气含量很少条件下保存时效果最佳。本研究可为核桃油乳液和微胶囊产品的均质和杀菌工艺选择以及应用提供理论依据。     

Influence of different solid lipids on the properties of a novel nanostructured lipid carrier containing Antarctic krill oil

This study aimed to investigate the effect of solid lipids (lauric acid (LAU), myristic acid (MYR), stearic acid (STE), glycerol monostearate (GMS), glycerol 1,3-distearate (GDS), glycerol tristearate (GTS), glycerol trimyristate (GTM) and glycerol trilaurate (GTL)) on the characteristics of novel nanostructured lipid carrier (NLC) containing Antarctic krill oil through ultrasound. The fatty acids (LAU, MYR, STE and GMS) were unsuitable solid lipid materials, as apparent stratification was quickly observed during the NLC preparation. NLCs were successfully prepared using GTS, GTM, GTL and GDS. The zeta potential of all NLCs exceeded −30 mV indicating good uniformity and stability. These NLCs appeared spherical or oval. Differential calorimetry and X-ray diffraction analysis revealed these NLCs formed imperfect crystals. As the carbon chain length of triglycerides increased from C₁₂ to C₁₈, the particle size of NLCs increased from 235.8 ± 2.3 nm to 340.5 ± 2.2 nm, the degree of recrystallisation increased from 39.06% to 49.99%, while the EPA encapsulation efficiency decreased from 88.72 ± 0.47% to 72.86 ± 1.06%. NLC prepared with GDS had the smallest particle size (112.4 ± 0.4 nm), the lowest recrystallisation and the highest EPA encapsulation efficiency (>99%). GDS was the most suitable to prepare high encapsulate efficiency krill oil-loaded NLC.     

Development and characterisation of a novel krill oil nanostructured lipid carrier based on 1,3-glycerol distearate

A novel nanostructured lipid carrier (NLC) loaded with Antarctic krill oil while using 1,3-glycerol distearate (GDS) as the solid lipid was prepared through ultrasonication. The NLCs were optimised for ingredient formulation by single-factor experiment on the basis of their effects on the particle size and polydispersity index (PDI) of the NLCs. 2% (w/w) lecithin and 10% lipid phase of which krill oil accounted for 50% (w/w) were applied to develop the optimised NLC dispersion. The particle size, PDI and zeta potential of this NLC were 112 nm, 0.270 and −30.8 mV, respectively, indicating good dispersion uniformity and stability. Transmission electron microscopy (TEM) revealed that the optimised NLC particles were spherical and uniformly dispersed without apparent aggregation. Differential calorimetry scanning (DSC) and X-ray diffraction (XRD) showed that the optimised NLC had less-ordered crystalline structure contributing to the high entrapment efficiency (> 99%) of EPA and DHA.     

Optimisation of the formulation of β-carotene loaded nanostructured lipid carriers prepared by solvent diffusion method

In this study, the optimised β-carotene loaded nanostructured lipid carriers (NLC) were prepared using the solvent diffusion method. Response surface methodology (RSM) was employed in conjunction with a central composite design (CCD) to evaluate the effect of the preparation variables on particle size and β-carotene stability to optimise the NLC formulation. Quadratic polynomial was the best fitted mathematical model for the experimental results. The statistical evaluations revealed that the lipid phase concentration and the surfactant concentration had significant effect on particle size of NLC. In addition, the influence of the liquid lipid to total lipid ratio and temperature on β-carotene degradation was more important. The optimum formulations with minimum particle size (8–15 nm) and low β-carotene degradation (0–3%) were derived from the fitted models and were experimentally examined which demonstrated a reasonable agreement between experimental and predicted values. Transition electron microscopy (TEM) observations exhibited spherical morphology of β-carotene loaded NLC.     

VC脂质体的制备与稳定性测定

以卵磷脂和胆固醇为膜材,采用薄膜- 超声法制备VC 脂质体。通过单因素考察生产工艺对包封率的影响以及正交设计法进行工艺优化。得出制备VC 脂质体最佳工艺：制备温度65℃、卵磷脂:胆固醇=5:1、总脂材:VC=25:1、总脂材:表面活性剂(吐温-80)=10:2,在此条件下包封率可达42.1%,平均粒度为373.9nm;将脂质体在4℃下密闭放置15d,以脂质体的粒径变化为指标考察其稳定性。结果表明,脂质体悬液粒径无明显变化,脂质体悬液稳定性良好。     

pH值偏移大豆油体-姜黄素复合乳液的物理特性及稳定性

以大豆油体为原料，利用油体天然水包油结构，借助pH值偏移法将姜黄素负载到油体油相内核中，制备姜黄素递送体系。通过乳液包封率、粒径、Zeta电位、显微结构等研究其包封特征，通过内源荧光光谱、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳分析其结构变化，探讨其贮藏稳定性、pH值稳定性及氧化稳定性。结果表明：大豆油体借助pH值偏移可成功包封姜黄素，pH值偏移为1.0时，大豆油体对姜黄素的包封效果最佳，乳液包封率为65.55%；脂滴形状规则、大小均匀，平均粒径为590.5 nm；氧化稳定性良好，但贮藏稳定性、pH值稳定性较差；蛋白质结构与未处理油体相比，未发生明显改变。本研究为天然油体运载姜黄素等亲脂性多酚物质提供一定参考。     

Preparation and Characterization of Novel Lipid Carriers Containing Microalgae Oil for Food Applications

This work investigated the suitability of lipid carriers as potential encapsulation method to improve the physical and chemical stability of microalgae oil high in docosahexaenoic acid (DHA). Lipid carriers with various oil contents were successfully prepared by a microfluidization method using stearic acid as solid lipid, microalgae oil as liquid lipid, and poloxamer 188 as surfactant. Results show that the mean particle diameter of the lipid carriers was in the range of 300 to 350 nm with the polydispersity index below 0.2. The lipid carriers were found to have spherical shape when examined under the transmission electron microscope. Data from the encapsulation efficiency and loading capacity indicate high distribution of microalgae oil throughout the lipid carriers and good physical stability as reflected by the particle size and size distribution during storage. Furthermore, the lower DPPH scavenging activity of lipid carriers compared with that of free microalgae oil suggests better chemical stability of microalgae oil encapsulated in lipid carriers. The addition of microalgae oil into lipid phase could disturb the crystalline order and form lattice defects to enable encapsulation of DHA as revealed by the results from differential scanning calorimetery. Current results suggest that this type of novel lipid carriers could be an efficient and promising carrier system for delivery of microalgae oil.     

均质工艺对制备鱼油微胶囊结构和理化性质的影响

本实验分别利用高压均质、空化射流和超声破碎3 种均质方式制备以大豆分离蛋白和磷脂酰胆碱包裹的鱼油纳米乳液和微胶囊,并对纳米乳液粒径、Zeta-电位、稳定性、黏度、乳化产率及微胶囊形貌、理化性质、稳定性进行比较分析,研究均质工艺对鱼油纳米乳液和微胶囊理化性质的影响。结果发现,空化射流工艺制备的纳米乳液平均粒径小,乳化产率和乳液稳定性较高,经过空化射流10 min制备的微胶囊包埋率达87.44%,溶解度较高,微胶囊颗粒表面形态饱满、致密、无裂纹和空隙,氧化稳定性和热稳定性较好。高压均质和超声破碎制得的纳米乳液平均粒径大,乳化产率和乳液稳定性较低,经过100 MPa高压均质和400 W超声破碎制得的微胶囊包埋率分别为80.36%和78.64%,溶解度相较于空化射流差,微胶囊颗粒表面分别出现微孔和较大的孔洞,氧化稳定性和热稳定性较差。傅里叶变换红外光谱分析结果表明3 种均质工艺均有较好的包埋效果。通过实验可以得出空化射流均质工艺制备的鱼油纳米乳液及微胶囊在产品性能上要优于其他两种均质工艺。本研究可为鱼油纳米乳液和微胶囊产品的均质工艺选择以及应用评价体系的构建提供理论依据。     

Application of nanostructured lipid carrier in food for the improved bioavailability

Nanostructured lipid carriers (NLC) could be used as suitable carriers of water-insoluble nutrients such as coenzyme Q10 (CoQ10) improve their bioavailability. The CoQ10-NLC was prepared by high-pressure homogenization method. The freshly prepared CoQ10-NLC showed ellipsoid morphology under atomic force microscope, and the average encapsulation efficiency was about 98.4 ± 0.3%. Good physical and chemical stability was observed by photon correlation spectrum and HPLC, respectively. In 3 months’ storage, the concentration of CoQ10-NLC kept at 8.5 ± 1.5 mg/mL; the particle size was 190 ± 30 nm with polydispersity index (PDI) lower than 0.1. Lyophilization was proved feasible for the storage of NLC dispersion. The formulation also showed the potent possibility of application on beverage. Particle size remained relatively steady in simulated beverage solution for 3 months. The oral bioavailability study was carried out using Wistar rats. The relative bioavailability of CoQ-NLC was about 200% compared with CoQ10 suspension. In conclusion, the NLC formulation showed good stability and improved bioavailability. It demonstrated a promising perspective for daily consuming and industrial production.     

Incorporation of phytosterols in soy phospholipids nanoliposomes: Encapsulation efficiency and stability

The objective of this work was to determine the effect of the incorporation of plant sterols on the stability and encapsulation efficiency of soy phospholipids vesicles. Small, unilamellar liposomes were prepared using high pressure homogenization at pH 7. Two types of commercial plant sterol preparations were employed: a water and oil soluble. The model hydrophilic molecule used for encapsulation efficiency studies was ascorbic acid. The lipid vesicles were prepared with a total lipid concentration of 150 mg mL^?1, and plant sterols were incorporated at two different phospholipid/plant sterol mix ratios: 14/1 and 13/2 (g/g). All the liposomes obtained showed an initial monomodal size distribution with an average diameter between 115 and 150 nm (with a coefficient of variation <10%), depending on the preparation. Incorporation of plant sterols increased the vesicle size and their encapsulation efficiency, regardless of the method of preparation. Dilution of the vesicles in imidazole buffer with or without glucose showed a reduction in the encapsulation over time in all cases, with differences in stability depending on the method of preparation. This work clearly showed that, when preparing liposomes using high pressure homogenization, the presence of plant sterols affects their colloidal stability and encapsulation efficiency.