卵黄高磷蛋白的研究进展

结合国内外关于卵黄高磷蛋白的最新研究动态,介绍了它的组成、提取、功能性质及其开发应用前景。卵黄高磷蛋白有着良好的热稳定性、抗氧化性及乳化性能,在一定条件下对大肠杆菌有致死作用,将之与半乳甘露聚糖连在一起,其功能性质有提高。卵黄高磷蛋白及其水解得到的磷酸肽类有很好的持钙性,这些生物活性肽能增加小肠对钙的吸收及其在体内的蓄积,也能促进铁、锌等离子的吸收,因此它作为潜在的功能食品因子将有良好的应用前景。     

On the use of ultrafiltration for the concentration and desalting of phosvitin from egg yolk protein concentrate

An ultrafiltration‐based approach was integrated in the preparation of phosvitin (PVs) from delipidated egg yolk proteins. An attempt was made to concentrate PVs as well as to desalt by means of the diafiltration technique. Primary experiments were devoted to optimise the ultrafiltration performance as function of parameters such as the effects of pH, feed concentration and transmembrane pressure on permeate flux with the 10‐kDa molecular weight cut‐off (MWCO) polyethersulfone membrane at laboratory scale. Higher permeate flux values were observed at low concentration and at alkaline pH, whatever transmembrane pressure studied. Then, desalting of PVs was carried out at 50 °C with 10‐ and 30‐kDa MWCO membranes. The results showed that desalting of PVs was obtained with both the 10‐ and 30‐kDa MWCO membranes and with a few loss of protein in the permeate side.     

Antioxidant activity of tryptic digests of hen egg yolk phosvitin

BACKGROUND: Food protein‐derived peptides with antioxidant activity have great potential for use as natural antioxidants in food products. However, neither the structure–activity relationship nor the antioxidant mechanism of peptides is fully understood. Egg yolk phosvitin has been acknowledged to have strongly antioxidant protein owing to its highly phosphorylated form. In this study the antioxidant activities of tryptic digests of hen egg yolk phosvitin (PPPs), which were prepared by partial dephosphorylation and subsequent hydrolysis by trypsin, were compared with that of intact phosvitin. RESULTS: Compared with intact phosvitin, PPPs exhibited distinctly stronger capability of inhibiting lipid oxidation in a linoleic acid system and more efficient radical‐scavenging activity on 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radicals. However, the chelating capability of PPPs on iron(II) was weaker than that of intact phosvitin. The strong antioxidant activity of PPPs can be mainly attributed to the amino acid composition rather than to the content of phosphorylserine ligands. Histidine, methionine and tyrosine are the amino acids most likely to be responsible for the strong antioxidant activity of phosvitin peptides. CONCLUSION: The present study indicated that PPPs could be used in foods as natural antioxidants with strong antioxidant activity. Copyright © 2007 Society of Chemical Industry     

Egg yolk phosvitin and functional phosphopeptides--review

Phosphopeptides are among the most interesting biomolecules with characteristic molecular structure and functions. They usually contain clusters of phosphoserines, which can effectively bind calcium and iron, and inhibit formation of insoluble calcium phosphates or iron complexes. Therefore, phosphopeptides can increase calcium or iron bioavailability and prevent lipid oxidation in foods. Milk protein casein has been currently used by industry to produce phosphopeptides. Egg yolk phosvitin is considered as the most phosphorylated protein found in the nature. Phosvitin from egg yolk can be much better source for producing phosphopeptides with varying sizes and functions than casein because it contains much greater number of phosphates in the molecule than casein. However, still phosvitin has not been subjected to considerable attention with regard to bioactive peptides production.     

Bioactivities of hen's egg yolk phosvitin and its functional phosphopeptides in food industry and health

Phosvitin, one of the most noteworthy bioactive components of hen egg yolk, is an amphiphilic protein that stands out with its unique composition and functionality in the food industry and health. Phosvitin consists of 4% of egg yolk dry matter and 11% of egg yolk proteins. It is considered as the most phosphorylated protein with 10% phosphorus. Besides, some potential novel phosphopeptides containing clusters of phosphoserines can be derived from hen's egg yolk phosvitin. Phosvitin, which has many functional features thanks to its unique structure, is known primarily for its metal bonds binding (iron, calcium, etc.) feature. On the other hand, its phosphopeptides may increase the bioavailability of metals compared to phosvitin. Although this feature of phosvitin may partially decrease the bioavailability of especially iron in the egg, it allows the phosvitin to have many bioactivities in the food industry and health. Lipid oxidation, which is a serious problem in the food industry, can be inhibited by adding phosvitin and its derived phosphopeptides to the food production chain via inhibiting bivalent iron. Because phosvitin is an amphiphilic protein capable of chelating, it also shows potential antibacterial effects against the Gram-negative bacteria. Moreover, the literature has recently been attempting to define the promising relationship between phosvitin and its phosphopeptides and plenty of health-promoting activities such as immune-enhancing, melanogenesis inhibitor, anti-ageing, and anticancer. In this review, current information on the hen's egg yolk phosvitin and its phosphopeptides and their bioactivities in the food industry and health are discussed and some future directions are given.     

关于鸡蛋黄、鸭蛋黄、咸鸡蛋黄、咸鸭蛋黄四种蛋黄风味物质的研究

咸蛋因其鲜嫩可口,营养丰富是一直深受国内外消费者喜欢的传统美食.尤其是咸蛋黄不仅可以直接食用,还被用于添加至月饼等糕点中,提高产品的口感与营养.鸡蛋、鸭蛋经腌制后产生了更多宜人的口感和风味.文章运用顶空微萃取技术与气质联用相结合的方法对鸡蛋黄、鸭蛋黄、咸鸡蛋黄和咸鸭蛋黄四种蛋黄进行了挥发性风味物质的研究.     

鸡蛋黄中天然活性物质的开发与利用

鸡蛋中蛋白质、脂类、碳水化合物、维生素、矿物质等营养成分含量丰富,是人类饮食的重要组成部分。鸡蛋黄中的蛋黄油、卵磷脂、卵黄高磷蛋白、免疫球蛋白等多种成分具有抑菌、抗氧化、提高免疫力、消炎、防癌等生理功能。目前,蛋黄中生物活性成分及其生产新技术的开发已经成为国内外研究的热点,部分成果已经实现了商业化应用。如何充分利用蛋中的活性物质并将其开发成具有治疗、保健功能的原料是蛋品科学与加工技术研究的一个主要课题。本文以蛋黄油、卵磷脂、卵黄高磷蛋白、免疫球蛋白4种物质的开发为主线,就鸡蛋黄中天然活性物质的含义、制备方法、生理功能、开发利用情况进行综述,以期为蛋黄中活性物质的进一步研究开发提供参考。     

脱脂蛋黄蛋白的限制性酶水解及酶解产物的应用研究

脱脂蛋黄蛋白(DEYP)是食品工业上提取蛋黄卵磷脂的副产物。研究了动物(胰蛋白酶)、植物(木瓜蛋白酶)和微生物(碱性蛋白酶、中性蛋白酶)三种来源蛋白酶的限制性酶解对DEYP功能性质的影响并对其酶解产物的应用进行初探。结果表明,酶解使DEYP的溶解性、起泡性(FC)和泡沫稳定性(FS)显著提高,乳化性适度改善;其中,胰蛋白酶对溶解性改善最显著,水解度(DH)8%时达49.21%;木瓜蛋白酶DH5%的酶解物FC高达DEYP的3.4倍,FS高达DEYP的2.5倍;碱性蛋白酶对DEYP的乳化性改善最明显,DH8%时酶解物的平均粒径达9.22μm。选择DEYP木瓜蛋白酶DH5%的酶解物作为起泡剂,部分替代蛋清制作蛋糕,替代率10%以内可制作出易打发且品质和原始相仿的天使蛋糕。DEYP酶解物为一种潜在的功能性配料,在食品行业显示出广阔的应用前景。      

Heat Denaturation and Emulsifying Properties of Egg Yolk Phosvitin

Phosvitin in water at pH 7 had a denaturation temperature (T_d) of 79.7 ± 1.4°C when heated at 10°C/min. When dissolved in 0.1M and 1.0M NaCl, the T_d decreased to 77.7 ± 1.2°C and 77.2 ± 1.3°C, resoectivelv. and in 10 and 20% sucrose there was no change in T_d. Heat treatment of phosvitin solutions at ≥65°C led to decreased emulsifying activity (EA). The emulsion stability (ES) decreased when phosvitim solutioni were heated at 70, 80 or 96°C for up to 60 min. The ES was not affected (p < 0.05) for phosvitin solutions after heating at ≤67.5°C for up to 60 min.     

Egg yolk protein modification by controlled enzymatic hydrolysis for improved functionalities

Delipidated egg yolk protein (EYP) is produced as a co-product of egg yolk lecithin extraction. This EYP is expected to have poor functionality because of protein denaturation caused by ethanol treatment during lecithin extraction. Two food grade endo-proteases were used to produce EYP hydrolysates (EYPh) with two degrees of hydrolysis (DH), 3% and 6%. Protein solubility was improved as DH increased. Solubility profiles for both EYP and EYPh were relatively less pH-dependent compared with soy protein. Except for foaming capacity, EYPh showed improvement in foam stability, foaming speed, and foam density. Emulsion stability was improved for all EYPhs. Treatments at DH of 6% showed significant increase in emulsification capacity. We have shown quantitatively how controlled enzymatic hydrolysis can be applied to ethanol-treated lipid-free EYP to increase protein solubility, and thus to improve foaming and emulsification properties.     

蛋黄免疫球蛋白的制备与应用

介绍蛋黄免疫球蛋白(IgY)的形成、特性、免疫程序、分离、提取、检测、应用等,重点为蛋黄免疫球蛋白的制备工艺。     

Egg yolk: structures,functionalities and processes

Hen egg yolk is an ideal example of natural supramolecular assemblies of lipids and proteins with different organization levels. These assemblies are mainly due to interactions between proteins and phospholipids, and these interactions are essential in understanding and controlling the production of food made with yolk, and particularly emulsions. Furthermore, these assemblies can be modulated by external constraints among which thermo‐mechanical and high‐pressure treatments. This review focuses on multi‐scale structures present in egg yolk, and their modulation by processes, in relation with their emulsifying properties. Egg yolk is mainly composed of two fractions—plasma and granules—which are natural nano‐ and micro‐assemblies. These two fractions possess different composition, structures and functionalities and exhibit specific behaviour under treatments such as high pressure and temperature. Plasma contains a large quantity of lipids structured as lipoproteins (low‐density lipoproteins), whereas granules are mainly composed of proteins aggregated in micrometric assemblies. If plasma is responsible for the important emulsifying properties of yolk, granules bring interesting emulsifying properties when assemblies are in the form of micelles in presence of salts. High‐pressure or thermal treatments, applied before or after emulsion fabrication, alter their functionalities and could be used to commercially exploit these fractions. © 2013 Society of Chemical Industry     

pH and Sodium Chloride Effects on Emulsifying Properties of Egg Yolk Phosvitin

The emulsifying properties of phosvitin dissolved in water and 0.1, 0.5 and 1.0 M NaCl were determined from pH 3 to 10. The change in its emulsifying activity (EA) with pH was slight but significant (p<0.05) and emulsion stability (ES) was relatively high (68-73%), except at pH 5 (17%) and 10 (48%). The EA of phosvitin was higher than that of bovine serum albumin (BSA) at pH 3 or 8 and ES was higher than BSA at all pH levels except at pH 5 and 10. Added NaCl decreased in the EA of phosvitin at pH 3 and 10 and decreased the ES between pH 3 and 9. Increased instability of emulsions resulted mainly in coalescence of oil droplets at NaCl ≥ 0.5M. Salt increased the viscosity of phosvitin emulsion only at pH 3 but not at pH > 5. The viscosities of BSA emulsions were higher than those of phosvitin at pH 3, 5 or 8.     

卵黄高磷蛋白酶解和脱磷对乳化性的影响研究

卵黄高磷蛋白被发现比别的食品蛋白质的乳化性尤其乳液稳定性高。蛋白酶和磷酸酯酶可使乳化活性和乳液稳定性明显降低;卵黄高磷蛋白的蛋白酶水解导致大肽链(高磷酸化核心区50～210个肽)和小肽链裂解(N-端1～49个肽和C-端211～217个肽);不含小肽的肽不具备优秀的乳化特性,蛋白质中一部分小肽在乳化特性中扮演着重要角色;磷酸酯酶处理后,卵黄高磷蛋白中磷酸酯的静电排斥力对乳化性有显著影响;磷酸充分作用后的残基的这部分蛋白质对高乳化特性至关重要。     

卵黄高磷蛋白磷酸肽的制备及钙结合性质研究

以卵黄高磷蛋白质为原料 ,经碱法脱磷、胰蛋白酶水解后分离制备得到一种新型的卵黄高磷蛋白磷酸肽 (PPP) .卵黄高磷蛋白质经 0 .1,0 .2 ,0 .3,0 .4mol/LNaOH处理 3h ,脱磷率分别为34.6 % ,81.6 % ,92 .5% ,96 .3% .SDS PAGE电泳结果显示 ,脱磷卵黄高磷蛋白质经胰蛋白酶水解后 ,产物为小分子肽 .经BaCl2 法和超滤法分离得到的磷酸肽的平均氨基酸残基数分别为 10个与2 0个 .对PPP的钙结合能力进行了研究并同商品化酪蛋白磷酸肽 (CPP)进行了比较 .PPP能有效地与钙络合 ,因而它在功能食品中有着较好的应用前景 .     

蛋黄卵磷脂的分离纯化研究进展

该文介绍了卵磷脂的理化性质、生理功能,综述了国内外对蛋黄卵磷脂的分离提取和精制方法及其在食品中的应用等方面的研究进展,展示了其在食品、药品等研究开发方面的广阔前景。