蛋黄卵磷脂的提取及测定

从蛋黄中提取卵磷脂有两种思路，即直接用乙醇提取再用丙酮沉淀和直接用丙酮处理再用乙醇抽提，本文在参考文献的基础上，经实验比较，得到较合理的路线，收率为80%-90％。     

蛋黄卵磷脂细菌内毒素检查法研究

目的:建立蛋黄卵磷脂辅料的细菌内毒素检查法。方法:依据《中国药典》2015年版四部通则1 143细菌内毒素检查法,通过干扰试验,确定蛋黄卵磷脂最大无干扰浓度,并进行方法学验证。结果:蛋黄卵磷脂浓度稀释到5 mg/mL及乙醇浓度稀释到5%以下时对细菌内毒素检测无干扰。结论:建立的方法可用于蛋黄卵磷脂的细菌内毒素检查。     

高效液相色谱法测定蛋黄卵磷脂中胆固醇的含量

应用高效液相色谱 蒸发光散射检测器测定蛋黄卵磷脂中胆固醇含量。采用Hy persilDOSC18(150mm×4.6mm,5μm)色谱柱,以乙腈∶甲醇∶异丙醇=10∶80∶10(v/v)为流动相,流速为1ml/min,柱温为25℃,蒸发光散射检测器的空气流速为2L/min,漂移管温度为85℃。胆固醇进样量在0 22～1 83μg的范围内与峰面积的对数呈良好的线性关系。相关系数为0 9998,回收率为99 59%。方法操作简便,精密度好,结果准确可靠。样品的测定结果为0 42%。     

用超临界二氧化碳萃取技术制备蛋黄卵磷脂的几种工艺探讨

介绍了蛋黄卵磷脂的功能用途、市场需求和生产工艺,对用超临界CO2萃取技术制备蛋黄卵磷脂的几种典型工艺进行了归纳、分析和比较,指出这些工艺产业化过程中存在的问题,并给出一些初步解决的方案。     

蛋黄卵磷脂反相囊泡在乙醛酸修饰碳纤维上的构建

利用乙醛酸修饰碳纤维制备了蛋黄卵磷脂反相囊泡,并通过倒置生物光学显微镜实现反相囊泡的原位表征。乙醛酸和蛋黄卵磷脂分子之间的氢键作用对双分子层磷脂膜的构建和反相囊泡的形成起着至关重要的作用。在2~3 d的较长时间内,在乙醛酸修饰碳纤维上构建的反相囊泡结构能够较好地保持。     

乙醇提取鸭蛋黄卵磷脂的工艺研究

采用正交实验和单因素实验方法,考察了提取温度、乙醇浓度、提取时间、料液比对鸭蛋卵磷脂提取率的影响。结果表明：在提取温度30℃、乙醇浓度92%、提取时间60min且料液比为1：5的条件下,从鸭蛋黄中提取卵磷脂的得率达9.92%。     

高纯卵磷脂的分离方法

卵磷脂是一种天然的表面活性剂，在食品、医药、化妆品等方面有重要的应用。本文详细介绍了卵磷脂分离提纯方面的研究成果，总结了溶剂法、层析法、超临界萃取等六种分离纯化卵磷脂方法的进展。     

大青木中黄酮苷的分离与结构鉴定

分离、鉴定了大青木中化学成分。采用反复硅胶柱色谱法、Sephadex LH-20柱色谱法和反复重结晶等方法进行分离纯化,并通过理化方法及1H-NMR、13C-NMR、DEPT、HSQC、HMBC等光谱分析确定化合物结构。从大青木中分离得1个化合物I,鉴定为5-羟基-3,7,3'-三甲氧基-4'-β-D-吡喃葡萄糖基黄酮甙,为首次从该植物中分离得到。     

蛋黄卵磷脂制备工艺及超临界CO_2脱蛋黄油实验研究

对用超临界CO_2萃取技术制备蛋黄卵磷脂的几种典型工艺进行了归纳、分析和比较。根据选择的工艺,对关键设备萃取器料筒进行了改进,通过正交试验,探讨了萃取压力、温度、时间、料筒层数等条件对蛋黄油脱除率的影响规律。     

超临界CO2萃取高纯度蛋黄磷脂

采用超临界二氧化碳萃取技术，从蛋黄粉中提取高纯度卵磷脂。实验条件为：温度35℃-60℃，压力25PMa-40MPa,Co2流量60kg/h-90kg/h，最佳条件为：温度55℃，压力36MPa-38MPa。结果表明磷脂纯度可达95%-98%。该方法解决了有机溶剂提取无法克服的缺陷。具有广阔的工业应用前景。     

Isolation of Pure Phospholipid Fraction from Egg Yolk

The phospholipid (PL) fraction from egg yolk was isolated and purified. In the procedure applied (method 2) the egg yolk was extracted with ethanol, precipitated using acetone chilled to −20 °C and washed using acetone. The purity of the samples was checked by HPLC analysis using a Charged Aerosol Detector (CAD). The results were compared with those obtained for the phospholipid fraction isolated and purified by deoiling yolk before extraction and the precipitation of PL with acetone chilled to 4 °C (method 1). The use of acetone chilled to −20 °C to precipitate and wash the phospholipids yielded the phospholipid fraction with 100% purity (78.7 ± 0.2 of phosphatidylcholine and 21.3 ± 0.2 of phosphatidylethanolamine). When deoiling and the 4 °C purification process was used (method 1) 0.4 ± 0.1% cholesterol and some traces of triacylglycerols remained in the PL fraction.     

鸡卵黄抗体(IgY)的诱导

目的　获得鸡卵黄抗体（Ｉｇｙ）,并研究该抗体在鸡的黄液中表达的进程。方法　用吗啡—牛血清蛋白 结合物为模型抗原对３０周龄产蛋鸡进行免疫诱导,用ＥＬＩＳＡ间接法测定不同时间的抗体滴度。结果全程免疫过 程中白蛋白抗体最高滴度为１：１２８００,吗啡抗体最高滴度为 １：１６００,经 ５次免疫后（４２周龄）抗体滴度不再升高。结论　为使目的抗体在鸡卵黄液中持续而高质量诱导奠定基础。     

Extraction of Phospholipids from Structured Dry Egg Yolk

Chicken egg yolk is a concentrated source of phospholipids (PL). Extracting egg PL with high efficiency is vital to the availability and economics of this high-valued lipid product. In this study, two types of structured dry egg yolk materials, yolk flakes and pellets, were prepared. Two commonly used solvents, hexane and ethanol, were tested on the extraction of total yolk lipids including the PL. The PL fraction was obtained by the conventional cold acetone precipitation. The drum-dried yolk flakes were shown to be an ideal starting material for total lipid and PL extraction. Anhydrous ethanol can extract almost all the neutral lipids and PL with little change to the individual components of the native PL. A PL product with a purity of more than 90 % and a yield of 99 % can be prepared using this method.     

Antioxidant and ACE Inhibitory Bioactive Peptides Purified from Egg Yolk Proteins

Protein by-products from the extraction of lecithin from egg yolk can be converted into value-added products, such as bioactive hydrolysates and peptides that have potential health enhancing antioxidant, and antihypertensive properties. In this study, the antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of peptides isolated and purified from egg yolk protein were investigated. Defatted egg yolk was hydrolyzed using pepsin and pancreatin and sequentially fractionated by ultrafiltration, followed by gel filtration to produce egg yolk gel filtration fractions (EYGF). Of these, two fractions, EYGF-23 and EYGF-33, effectively inhibited the peroxides and thiobarbituric acid reactive substance (TBARS) in an oxidizing linoleic acid model system. The antioxidant mechanism involved superoxide anion and hydroxyl radicals scavenging and ferrous chelation. The presence of hydrophobic amino acids such as tyrosine (Y) and tryptophan (W), in sequences identified by LC-MS as WYGPD (EYGF-23) and KLSDW (EYGF-33), contributed to the antioxidant activity and were not significantly different from the synthetic BHA antioxidant. A third fraction (EYGF-56) was also purified from egg yolk protein by gel filtration and exhibited high ACE inhibitory activity (69%) and IC₅₀ value (3.35 mg/mL). The SDNRNQGY peptide (10 mg/mL) had ACE inhibitory activity, which was not significantly different from that of the positive control captopril (0.5 mg/mL). In addition, YPSPV in (EYGF-33) (10 mg/mL) had higher ACE inhibitory activity compared with captopril. These findings indicated a substantial potential for producing valuable peptides with antioxidant and ACE inhibitory activity from egg yolk.     

Extraction of Phospholipids from Egg Yolk Flakes Using Aqueous Alcohols

Two alcohols, ethanol and butanol, with different water contents were evaluated for phospholipids (PL) sequential extraction from drum dried egg yolk flakes. It showed that butanol was more effective in extracting total yolk lipids compared to ethanol, but the PL in the extract had the same concentration as in the original yolk total lipid. The use of aqueous ethanol of 95 and 75% resulted in lipid extracts with higher PL concentration during the initial stages of the sequential extraction. When ethanol was further diluted to a concentration of 55%, the solvent lost its PL extraction ability, and the total lipid recovery also decreased dramatically. When both the PL purity and recovery were considered, 75% ethanol was the most effective aqueous alcohol for PL extraction and enrichment from the yolk flakes. In the first stage of extraction using such a solvent, 67% of the total PL in the original yolk was recovered in a lipid fraction with a PL purity of 75%. This study identified the optimal ethanol concentration for PL extraction from dried egg yolk. With this information, the best solid:solvent ratio can be designed to extract and enrich the polar lipids from lipid-bearing materials with known moisture content using a renewable or “green” solvent, ethanol.     

Egg Yolk as Means for Providing Essential and Beneficial Fatty Acids

The new American Dietary Guidelines now recommend optimizing the types of fat consumed instead of reducing or eliminating fat from the diet. Chicken eggs are a means to deliver essential and beneficial human dietary fatty acids (FA), and can be staple component of healthy eating behavior. Additionally, polyunsaturated fatty acids can be increased in the avian egg yolk by simply incorporating selected lipid sources into the avian diet. Poultry feed rich in omega‐3 FA (omega‐3) has allowed commercialization of enriched eggs containing up to 600 mg of omega‐3. Conjugated linoleic acid (CLA) has also been used in the research setting to enrich eggs to provide a portion of the 3–4 g CLA day^?1 needed to promote weight loss to combat obesity. However, Americans consume only 50% of the omega‐3 recommended adequate intake, and average CLA consumption is under 600 mg day^?1. While a variety of foods are naturally rich in omega‐3, conventional sources of CLA are limited to bovine milk and meat, which do not provide enough CLA to produce clinical effects in a balanced diet. Since eggs and egg‐based products are common in the Western diet, eggs enriched with both omega‐3 and CLA using dietary additions to poultry feed may promote consumption of the recommended levels of these FA. This article reviews the design of poultry eggs with enhanced lipid profiles through dietary intervention, and discusses the future direction of enriched egg research.     

An X-Ray Study of Phosvitin,The Phosphoglycoprotein in Hens' Egg Yolk

An X-ray diffraction study has been made of the egg-yolk phosphoglycoprotein, phosvitin. Film specimens prepared from an aqueous solution of pH 3.3 give an oriented fibre pattern showing features characteristic of β-pleated-sheet structures. However, X-ray patterns of specimens derived from solutions of pH 7.3 show no evidence of any ordered conformation. These results bear out reports, based on physiochemical studies of phosvitin in solution, of a pH-dependent conformational transition.     

抗轮状病毒IgY的研制

目的用鸡卵黄制备抗轮状病毒（ＲＶ）免疫球蛋白,预防和治疗婴幼儿ＲＶ感染。方法制备ＲＶ 抗原,通过不同途径免疫母鸡,几种纯化方法联合应用从鸡卵中提取特异性鸡卵黄抗体（ＩｇＹ）,进行理化学检定及动 物效力实验。结果免疫母鸡均可产生特异性ＩｇＹ,纯度可达９１％以上,产量为４４ｍｇ／蛋;可保护乳鼠兔受ＲＶ攻击; ＩｇＹ耐热、耐酸,室温保存半年、４℃两年效价不变。结论已成功地应用ＲＶ免疫母鸡制备出高效价特异性抗ＲＶ－ＩｇＹ。