汤中物质的溶出、迁移以及微纳米颗粒形成的研究进展

目前,浓缩罐头汤和干燥汤料包等产品在市场上的出现,代表了现代食品科技对汤口味、营养和保质期等方面深入研究的程度,但是对汤功能性的研究却鲜见报道。对汤功能性的研究首先要以汤功效性的研究为基础,而汤发挥其功效性的主要因子是汤中的微纳米颗粒。本文综述了目前汤中微纳米颗粒主要成分的种类,营养物质从食材迁移到汤中的规律以及微纳米颗粒可能的形成机制的研究进展,以期能够了解汤中微纳米颗粒与人体健康的关系。     

河蚬汤纳米颗粒细胞毒性及对大鼠腹腔巨噬细胞吞噬功能的影响

许多传统食品中存在大量的伴生性纳米颗粒,其纳米尺度的构造赋予它们特殊的活性与功能,然而这类纳米颗粒对人体细胞的影响尚未被充分揭示。以河蚬汤及其伴生纳米颗粒为例,采用狗肾上皮细胞(MDCK)、人结肠腺癌细胞(Caco-2)、人正常肝细胞(L-02)和大鼠原代腹腔巨噬细胞模型,研究以液相色谱方法分离制备的河蚬汤纳米颗粒的细胞毒性,以及其对大鼠原代腹腔巨噬细胞功能的影响。实验结果表明:15.63~500.00μg/mL河蚬汤伴生纳米颗粒对4种细胞均无明显毒性;这些纳米颗粒能被大鼠原代腹腔巨噬细胞吞噬,对正常巨噬细胞的膜电位和吞噬功能无明显影响,抑制AAPH诱导氧化应激引起的细胞膜超极化,拮抗线粒体的氧化应激与细胞吞噬功能损伤。抗氧化测试结果显示,河蚬汤伴生纳米颗粒具有FRAP、ABTS抗氧化活力,但不具有ORAC活性。研究旨在为后续深入开展河蚬汤及其伴生纳米颗粒的功效以及作用机制提供必要的基础数据和理论支持。     

河蚬汤中纳米颗粒作用于大鼠口腔巨噬细胞的研究

食品加工过程中,食品成分的自组装行为会产生大量微纳米级别的胶体颗粒。这类胶体颗粒在人体的吸收、转运及其生理功能尚不完全明确。本文研究了河蚬汤中的纳米颗粒对消化道黏膜免疫细胞的影响。在消化道黏膜来源的巨噬细胞模型中,观测该纳米颗粒进入细胞的过程以及对细胞毒性、细胞膜电位和线粒体超氧自由基的影响。结果显示:河蚬汤纳米颗粒无明显细胞毒性,可进入巨噬细胞胞内并保持颗粒结构,可以改善巨噬细胞的氧化应激状态。本研究结果提供了食品纳米颗粒与免疫细胞之间直接相互作用的证据,揭示了一种食品与人体相互作用的方式。     

金属纳米颗粒-刺激响应型水凝胶：活性成分递送体系研究进展

刺激响应型水凝胶活性成分递送体系因其对不同环境具有独特的溶胀和降解特性,在食品、医药等领域已有广泛研究。然而,部分水凝胶作为活性成分递送载体时存在荷载效率和靶向释放效率低等问题。基于金属纳米颗粒具有高比表面积和多孔结构的特点,可增强刺激响应型水凝胶的活性成分荷载能力。将金属纳米颗粒和刺激响应型水凝胶杂化制备得到的复合材料,在环境响应型的活性成分递送和控制释放领域已得到大量研究。论文综述了金属纳米颗粒-刺激响应型水凝胶复合材料的特点、种类和制备方法,总结了其在活性成分递送领域的应用,并对其作为递送体系的未来发展进行了展望。     

基于网络药理学与分子对接技术的保健食品白及五味子颗粒保胃护肝作用机制和功效成分含量测定研究

基于网络药理学和分子对接筛选辨识白及五味子颗粒中保胃护肝的功效成分及作用机制,并利用HPLC-DAD建立含量测定方法。该研究遵循多个功效成分共同测定取代总成分测定以提升保健食品质量控制总体思路,采用网络药理学的方法对功效成分进行筛选。基于TCMSP、GEO和Genecards等数据库共收集白及五味子颗粒的59个目标成分和74个疾病与成分的共同作用靶点,采用PPI平台及“成分-靶点-疾病”网络筛选得到包括AKT1、JUN等11个核心靶点与橙皮苷、芒柄花素、川陈皮素、五味子醇甲、五味子甲素和五味子乙素共6个功效成分。通过对共同作用靶点进行GO和KEGG富集分析可知,白及五味子颗粒保胃护肝功能的发挥涉及对化学应激的反应、类固醇代谢过程、对酒精的反应、脂质和动脉粥样硬化通路、IL-17信号通路等关于脂质代谢、氧化应激和炎症反应的通路。提示了白及五味子颗粒发挥保胃护肝功能是通过多成分、多靶点、多通路的协同作用实现的。对筛选得到的功效成分与核心靶点的结合能力进行预测分析,结果显示,所有成分均与核心靶点结合情况良好,结合活性综合排名前3位分别是橙皮苷、五味子醇甲与五味子甲素。此外,对功效成分建立含量...     

纳米竹炭纺织品中纳米竹炭的检测方法研究

利用场发射环境扫描电镜、激光显微拉曼光谱、热重分析等手段表征了纳米竹炭纺织品中纳米竹炭的形貌、成分和含量,并检测了制品的远红外性质.结果表明:在所检测的制品中,纤维内部及表面均存在亚微米竹炭颗粒,质量分数较低,添加后使该纺织品的远红外性能得到一定程度的提高.纳米产品中纳米组分存在形态与性质的鉴别为评价纳米产品功能的关键环节.这些研究方法的建立和研究结果有望为下一步发展针对各种纳米制品的检测表征规范提供参考.     

新加坡研究指出食品与化妆品中的纳米级氧化锌有致癌风险

据foodnavigator.com网站消息,近日《生物材料》杂志刊登新加坡南洋理工大学的一项研究发现,包括防晒霜、食品添加剂等在内的一系列日常消费品含有纳米级氧化锌这种成分,而纳米级氧化锌微粒可破坏人体基因,可能具有致癌风险。研究发现,当纳米级氧化锌入侵人体后,人体内P53这种抑癌基因会起到抑制肿瘤生成的功效,     

保健食品功效成分测定方法现状及发展趋势

按照<保健食品管理办法>的要求,企业在申报保健食品时应提供产品的功效成分和功效成分的定性、定量测定方法,并说明功效成分在保健食品中所处地位.功效成分是保健食品保健功能的关键所在,也是产品质量的主要指标,国内外对保健食品(功能食品)的开发研究都十分重视功效成分的研究.1999年1月在北京举办的保健食品国际研讨会上,中外学者一致认为保健食品要长期稳定地健康发展,必须首先明确功效成分,解决功效成分的测定方法,特别是以草本植物为原料的保健食品,弄清其功效成分更有着极其重要的意义.我国传统的保健食品长期在低水平徘徊,没有确定功效成分及解决功效成分的测定方法是一个主要因素.     

柚皮素及其纳米递送体系研究进展

柚皮素是广泛存在于柑橘类水果中一种黄酮类化合物,具有多种生理功效,如抗肿瘤、抗氧化和抗炎活性等。然而,由于柚皮素的疏水性,导致其生物利用度较差,应用潜力受到阻碍。为了提高柚皮素的生物利用度,研究人员开发了包括聚合物纳米颗粒、脂质体、纳米乳液、纳米混悬液在内的纳米递送系统。在此,该文对柚皮素的生理功能、体内代谢及其纳米递送体系进行了介绍,针对目前研究中存在的问题对未来柚皮素纳米递送体系的研究方向和应用前景进行了展望。     

三七的超细化及纳米化研究

简述了三七的成分、功效和临床应用,以及超微粉碎技术在中药加工中的应用优势和纳米中药与微米中药的概念。并分别采用干法球磨、气流粉碎和湿法球磨3种方法对三七进行超细化加工,结果获得了微米三七粉和三七纳米混悬剂。这为三七超细加工的规模化生产以及纳米化加工研究提供了一定的依据。     

Lipid nanoparticles (SLN & NLC) for delivery of vitamin E: a comprehensive review

The antioxidative and photoprotective properties of vitamin E have caused it to be included as an active agent in various pharmaceutical and cosmetic products. However, its lipophilicity, chemical instability and poor skin penetration have limited the effectiveness of these formulations. For that reason, many attempts to include it in different drug delivery systems have been made. In recent decades, lipid nanoparticles have received special attention due to their advantages of compatibility with the skin, ability to enhance penetration of drugs in the stratum corneum, protection of the encapsulated substance against degradation induced by the external medium and control of drug release. This work reviews the current status of the encapsulation of vitamin E in lipid nanoparticles. We describe the most important methods for obtaining and characterizing lipid nanoparticles containing vitamin E (LNP‐VE), various techniques for the evaluation of vitamin E's properties after encapsulation, the main in vitro and in vivo studies of the potential effectiveness or toxicity of LNP‐VE, the formulations and stability studies of this delivery system, the commercial products based on LNP‐VE and the regulatory aspects related to lipid nanoparticles. Finally, we discuss the most relevant advantages of encapsulating vitamin E in such particles and critical aspects that still demand attention to enhance the potential of solid lipid nanoparticles to deliver vitamin E.     

Quercetin-Loaded Lecithin/Chitosan Nanoparticles for Functional Food Applications

This study aimed at the encapsulation of quercetin into lecithin/chitosan nanoparticles using the electrostatic self-assembly technique, followed by evaluation of their functionality (antioxidant activity) and stability at different environmental conditions. These nanoparticles were characterized in terms of: average size, morphology, zeta potential, encapsulation efficiency, loading, and spectroscopic characteristics. Quercetin has been successfully encapsulated in lecithin/chitosan nanoparticles with an efficiency of 96.13?±?0.44 %. Nanoparticles presented a spherical morphology with an average size of 168.58?±?20.94 nm and a zeta potential of 56.46?±?1.94 mV. Stability studies showed that nanoparticles are stable to temperatures ranging between 5 and 70 °C and a pH variation from 3.3 to 5.0. Moreover, encapsulated quercetin showed improved antioxidant properties when compared to free-quercetin. Our results suggest that quercetin-loaded lecithin/chitosan nanoparticles can be used in the manufacture of functional foods.     

In Situ Generation of Bimetallic Nanoparticles in Cotton Fabric Using Aloe Vera Leaf Extract,as a Reducing Agent

ABSTRACT

In the present work, bimetallic nanoparticles were in situ generated in cotton fabrics using Aloe Vera extract as reducing agent. The nanocomposite cotton fabrics were prepared, individually with 5 mM concentrations of Ag and Cu salt solutions and equi.molar concentration of their combination, characterized by FTIR, XRD, SEM, EDX, and antibacterial tests. FT-IR studies reveal that nitro compounds and hydroxyl groups are involved in reduction of the metal salts into their metal nanoparticles. The nanocomposite cotton fabrics have shown good antibacterial activity for five bacteria. These fabrics can be used for dressing, wound healing, packaging, and medical applications.     

The dissolution rates of SiO2 nanoparticles as a function of particle size

There is a critical need to better define the relationship among particle size, surface area, and dissolution rate for nanoscale materials to determine their role in the environment, their toxicity, and their technological utility. Although some previous studies concluded that nanoparticles dissolve faster than their bulk analogs, contradictory evidence suggests that nanoparticles dissolve more slowly. Furthermore, insufficient characterization of the nanoparticulate samples and the solution chemistry in past studies obscures the relationship between particle size, surface area, and dissolution rate. Here we report amorphous SiO(2) dissolution rates in aqueous solutions determined from complementary mixed-flow and closed reactor experiments at 6.9 ≥ pH ≥ 11.2 and 25 °C as a function of particle diameter from 25 to 177 nm. Experiments were performed at far-from-equilibrium conditions to isolate kinetic effects from those of changing the reaction driving force on overall dissolution rates. Measured far-from-equilibrium mass normalized dissolution rates are nearly independent of particle size, but corresponding BET surface area normalized rates decrease substantially with decreasing particle size. Combining these observations with existing established kinetic rate equations allows the prediction of nanoparticle dissolution rates as a function of both particle size and aqueous fluid saturation state.     

Antibacterial properties of silk fabric treated with silver nanoparticles

Silk is hygroscopic and is affected by microorganisms easily. Hence, treatment with antimicrobial agents can facilitate to make silk resistant to microbes. Silver nanoparticles have been attempted by researchers and applied as antimicrobial chemical finish on textiles. Silk has also been applied with silver nanoparticles through exhaust method to obtain antimicrobial properties. However, use of cross-linking agents such as 1,2,3,4 butane tetra carboxylic acid (BTCA) for entrapping silver nanoparticles in the interstitials of the silk molecular chain has not been attempted. The present study is focused on the application of BTCA on silk in the presence of sodium hypophosphite (SHP) simultaneously using silver nanoparticles has been done by pad-dry-cure (2dip/2nip) method. Application of 6% BTCA with 3% SHP and 250 ppm of silver nanoparticles gave satisfactory antimicrobial properties. Infrared spectroscopic (FTIR) studies showed good cross-linking of BTCA. X-ray diffraction studies depict that the crystal structure and crystallinity % of treated silk did not change due to the treatment. SEM studies showed the impregnation of silver nanoparticles on to the fibre matrix. Different physical properties of silk fabric did not change due to the treatment. Based on the studies, it is inferred that BTCA cross-links with silk fibroin at the carboxyl and amine groups, create a lattice void and trap silver nanoparticles giving durable antimicrobial finish.     

负载山奈酚的小麦醇溶蛋白纳米颗粒的制备及其抗氧化活性研究

近年来,越来越多的研究证实血管病变的发生和发展与氧化应激密切相关,而山奈酚作为黄酮类化合物具有良好的抗氧化活性。本研究通过反溶剂法制备出的山奈酚-小麦醇溶蛋白纳米颗粒的粒径在200 nm左右,粒子均一,使用去离子水复溶后仍然具有良好的分散性并在28天的时间里保持其稳定性。傅里叶变换红外光谱的分析结果表明,山奈酚主要通过氢键、疏水作用以及静电作用与小麦醇溶蛋白相互结合。与游离的山奈酚相比,纳米粒子具有更好的生物相容性,在体外具有显著的抗氧化能力,可以显著地清除细胞内的活性氧。总体而言,山奈酚-小麦醇溶蛋白纳米颗粒具有良好的生物相容性,同时可以显著提高其抗氧化活性,这为山奈酚的临床应用提供了新的途径。     

Mucus and microbiota as emerging players in gut nanotoxicology: The example of dietary silver and titanium dioxide nanoparticles

Given the growing use of nanotechnology in many common consumer products, including foods, evaluation of the consequences of chronic exposure to nanoparticles in humans has become a major public health issue. The oral route of exposure has been poorly explored, despite the presence of a fraction of nanosized particles in certain food additives/supplements and the incorporation of such particles into packaging in contact with foods. After their ingestion, these nanoparticles pass through the digestive tract, where they may undergo physicochemical transformations, with consequences for the luminal environment, before crossing the epithelial barrier to reach the systemic compartment. In this review, we consider two examples, nanosilver and nanotitanium dioxide. Despite the specific features of these particles and the differences between them, both display a close relationship between physicochemical reactivity and bioavailability/biopersistence in the gastrointestinal tract. Few studies have focused on the interactions of nanoparticles of silver or titanium dioxide with the microbiota and mucus. However, the microbiota and mucus play key roles in intestinal homeostasis and host health and are undoubtedly involved in controlling the distribution of nanoparticles in the systemic compartment.     

Nanoclay migration from food packaging materials

A recent trend is to use nanocomposites materials for food-packaging applications. Different kinds of nanoparticles are incorporated into the polymers to improve their characteristics, and, among them, nanoclay is used to improve their barrier properties to gases. In this work, the results of migration studies with different food simulants (ethanol 10% and acetic acid 3%), temperatures and times (40ºC for 10 days and 70ºC for 2 h) from two commercialised LDPE nanocomposite bags are presented. The migration solutions thus obtained were analysed by ICP-MS to evaluate the amount of aluminium which migrated into the solutions both in dissolved form and as a part of nanoparticles. Aluminium migration was observed for both samples with a maximum migration value of 51.65 ng cm^–2 for the Aisaika bags and 24.14 ng cm^–2 for the Debbie Meyer bags. The presence of spikes working in single-particle mode using ICP-MS indicated that part of this aluminium was present as nanoparticles. The size and morphology of the nanoclay, in both the original material and the migration solutions, was studied by scanning electron microscopy coupled to energy-dispersive X-ray diffraction (SEM-EDX). In this manner, nanoparticles of different morphologies and sizes were found to migrate into the food simulants.     

薏米淀粉纳米颗粒的制备及理化特性

以薏米淀粉为原料，采用3种不同纳米淀粉法体系（碱溶体系、水-乙醇体系、二甲基亚砜（dimethyl sulfoxide,DMSO）-乙醇体系）制备薏米淀粉纳米颗粒。通过颗粒特性、分子特性、结晶特性和热特性等对比研究3种不同薏米淀粉纳米颗粒的结构和理化特性。结果表明：碱溶体系制备的纳米颗粒具有最高的纳米颗粒占比（85.65%），碱溶体系和水-乙醇体系制备的纳米颗粒呈现A型结晶结构，而DMSO-乙醇体系制备的纳米颗粒的晶型结构由A型转变成无定形结构。通过对比分析可知，在45℃条件下碱溶体系制备的薏米淀粉纳米颗粒拥有最小的粒径（348 nm）、最高的多分散系数，较高的有序度、相对结晶度和热稳定性，是制备薏米淀粉纳米颗粒的最佳纳米沉淀法体系。该研究为制备淀粉纳米颗粒及其结构特性研究以及拓展薏米淀粉的应用提供一定理论依据。     

蛋白质纳米颗粒的制备及其在食品领域的应用研究进展

蛋白质纳米颗粒即纳米级的蛋白质颗粒，由于蛋白质本身具有良好的生物相容性和生物降解性，与合成纳米材料相比，蛋白质纳米颗粒在生物活性物质的包埋和传递方面具有极大优势，近年来逐渐成为研究的热点。本文首先介绍了目前主要用于食品工业的动物蛋白纳米颗粒和植物蛋白纳米颗粒的常见类型，并对蛋白质纳米颗粒的常用制备方法进行了归纳总结，包括反溶剂沉淀法、盐析法、纳米喷雾干燥法、静电纺丝法、超临界流体法和热致聚集法等，分析了各种方法的原理及在安全性、适用性、产品质量和操作复杂程度等方面的优缺点，然后对蛋白质纳米颗粒在功能性食品的生产、食品的活性包装和食品Pickering乳液的稳定三个方面的应用进行了综述，最后归纳了蛋白质纳米颗粒应用安全性方面的研究现状，以期为蛋白质纳米颗粒的进一步研究提供理论参考。