大豆肌醇磷脂的表面活性研究

研究了肌醇磷脂(PI)含量为30%～75%的大豆磷脂的润湿性能、乳化性能和界面张力,并与粉状大豆磷脂表面活性进行了比较。PI含量为50%的大豆磷脂的润湿性能优于PI含量低于50%的大豆磷脂的润湿性。随着PI含量的增加,大豆磷脂对石蜡、柴油、豆油及苯的乳化性能逐渐增强;当PI含量为75%时,其乳化能力接近OP(壬基酚聚氧乙烯醚)。不同组分的大豆磷脂的界面张力不同。高卵磷脂含量(72%)的大豆磷脂的界面张力降低值低于高PI含量(50%)的大豆磷脂。      

药品大豆磷脂散的适应症研究

药品大豆磷脂散是国家食品药品监督管理局批准大豆磷脂类药品新剂型,是上海金伴药业有限公司沿袭上海油脂一厂四十余年研发大豆磷脂药品历史,自主研发申报新品种。大豆磷脂散主要功效成份为大豆磷脂,由于磷脂是人体细胞膜重要组成部分,广泛存在于人体各组织器官中,对人体功能产生重要影响。但作为药品,必须突出个性功能,经研究表明,大豆磷脂散适应症:可用于脂肪肝、肝炎、肝硬化、中毒性肝炎、动脉粥样硬化、及神经衰弱等。     

饲用大豆磷脂应用价值及制取工艺

我国饲用大豆磷脂主要为浓缩大豆磷脂和粉末大豆磷脂,系由大豆毛油精炼过程中水化脱胶副产物在真空下干燥脱水、纯化处理,再萃取、分离、干燥而得。该文概述饲用大豆磷脂组成、功能特性、应用价值及其制取工艺。     

大豆磷脂的制备、功能特性及行业应用研究进展

大豆磷脂是从大豆中提取的磷脂类混合物,具有多种重要的功能特性和巨大的应用价值.该文主要介绍了大豆磷脂的制备工艺、功能特性,及近年来关于大豆磷脂应用的研究进展,并对大豆磷脂未来的发展前景做了简要分析,以期为我国大豆磷脂行业的进一步发展提供参考.     

大豆肌醇磷脂的表面活性研究

研究了肌醇磷脂(PI)含量为30%～75%的大豆磷脂的润湿性能、乳化性能和界面张力,并与粉状大豆磷脂表面活性进行了比较.PI含量为50%的大豆磷脂的润湿性能优于PI含量低于50%的大豆磷脂的润湿性.随着PI含量的增加,大豆磷脂对石蜡、柴油、豆油及苯的乳化性能逐渐增强;当PI含量为75%时,其乳化能力接近OP(壬基酚聚氧乙烯醚).不同组分的大豆磷脂的界面张力不同.高卵磷脂含量(72%)的大豆磷脂的界面张力降低值低于高PI含量(50%)的大豆磷脂.     

大豆粗磷脂中磷脂酰胆碱的分离纯化研究

为了筛选出从醇溶性大豆磷脂中分离纯化大豆磷脂酰胆碱的最佳分离纯化工艺,本文了采用正交设计试验筛选提取大豆磷脂酰胆碱的最佳工艺。结果表明大豆磷脂酰胆碱最佳提取工艺为:按1∶10的料水比进行加热,在78℃恒温下4 h回流提取,重复2次。大豆磷脂酰胆碱的进一步的精制方法为葡聚糖凝胶Sephadex LH-20凝胶柱层析法,并且考察了葡聚糖凝胶Sephadex LH-20对大豆磷脂酰胆碱的纯化能力。首先采用无水乙醇作为葡聚糖凝胶Sephadex LH-20凝胶柱层析洗脱液纯化大豆磷脂酰胆碱,然后将所得的大豆磷脂酰胆碱干燥,最后通过高效液相色谱法对所得的大豆磷脂酰胆碱进行含量测定。结果表明,乙醇提取法以及葡聚糖凝胶Sephadex LH-20柱层析法相结合的纯化过程对大豆磷脂酰胆碱分离纯化效果良好,此外该方法收率高,能够得到纯度为90.12%的大豆磷脂酰胆碱。     

测定大豆磷脂酸价的指示剂选择

<正> 在大豆磷脂各项质量指标中,酸价是最重要的指标之一。酸价的高低最能体现产品的新鲜程度、加工工艺先进性及保管条件,是用户首选指标。 测定大豆磷脂酸价根据行业标准采用滴定法。将大豆磷脂溶解于石油醚中,再加中性乙醇,然后用氢氧化钾标准溶液滴定。根据称取的大豆磷脂质量、氢氧化钾消耗的体     

HPLC-ESLD法分离测定大豆磷脂酰胆碱

通过HPLC-ELSD对大豆磷脂中的大豆磷脂酰胆碱进行了分离和检测.使用硅胶柱,以三氯甲烷-甲醇(88/12,V/V)为流动相,大豆磷脂酰胆碱在10 min内出峰.该法具有比HPLC-UV有更少的干扰、更高的检测灵敏度和更节省时间,同时该法具有良好的线性关系、分析准确度和分析精密度.该法可以方便地检测大豆磷脂中大豆磷脂酰胆碱的含量.     

大豆磷脂中磷脂酰胆碱稳定性研究

目的研究大豆磷脂中磷脂酰胆碱在一定环境中的稳定性。方法将大豆磷脂与不同物料混合,考察配方配伍实验、不同p H值、不同温度对大豆磷脂中磷脂酰胆碱(phosphatidyl choline,PC)的稳定性。结果磷脂酰胆碱在大豆磷脂、基质油、抗氧化剂、甘油、明胶、焦糖色等混合中,其含量较稳定无多大变化。在p H4.5~8.5环境中PC含量相对稳定。大豆磷脂在温度≤47℃氮气保护环境下保温40 h,其PC含量相对稳定。结论在一定的环境中,配方配伍、pH值、温度对磷脂酰胆碱稳定性无多大影响。但大豆磷脂遇水后PC含量快速下降,故在生产或贮存过程中大豆磷脂要避免与水接触或长期暴露在空气中,在保温或贮存过程建议温度不高于50℃。     

大豆磷脂组成与特性

本文介绍了大豆磷脂的组成、理化特性及大豆磷脂在食品中的应用。     

磷脂加脂剂的综述与探讨

本文分析了天然磷脂的来源及化学组成，并对利用磷脂制备皮革加脂剂的方法及涉及到的问题进行了讨论，提出了进一步利用磷脂的设想。     

磷脂结构、膳食来源及营养学研究进展北大核心CSCD

磷脂是一类复合极性脂质,拥有独特的生理活性,对维持机体正常生命活动以及营养健康起着至关重要的作用。为了对膳食磷脂的营养学研究以及相关代谢疾病的预防提供参考,对磷脂的结构组成与生理活性、膳食来源及其营养学特性进行了综述。根据分子结构,磷脂可以分为不同的类型,也具有不同的生理功能以及营养特性;此外,磷脂的膳食来源丰富,但不同膳食来源的磷脂组成及含量存在差异。不同类型磷脂在改善记忆、提高免疫力以及预防心脑血管等代谢性疾病方面都发挥着很大的作用。     

Evolution and distribution of phospholipids in cheese and whey during the manufacturing of fresh cheese from cows' milk

In this study, we report on the evolution of phospholipid contents and their distribution in cheese and whey, during the production of fresh cheese. We found that the phospholipid content in the total mass of whey and fresh cheese together was greater than the content of phospholipids in the starting milk used to make them. This increase was probably due to bacterial growth during fermentation and the consequent synthesis of phospholipids to generate cell membranes. In the coagulation process, ≈20% of the phospholipids were drained in the whey. Based on this result, we conclude that whey might be an interesting source of phospholipids, mainly phosphatidylethanolamine and sphingomyelin, for the food industry.     

Association of plasma insulin concentration to fatty acid distribution between milk fat and membrane synthesis

We examined the association between plasma insulin concentration and fatty acid distribution to milk fat and membrane fractions (triglyceride and phospholipid, respectively) in dairy cows. Thirty-seven Holstein cows at 60 to 70 d postpartum were synchronized by 2 PGF(2α) injections 14 d apart. Plasma samples were taken before morning and evening milkings and milk samples were obtained at morning milking. Plasma insulin concentrations were determined and cows were retrospectively assigned to low insulin (LI; 2.8±0.2 ng/mL, n=6) or high insulin (HI; 5.9±0.6 ng/mL, n=7) experimental groups. Fatty acid analysis of milk samples demonstrated a possible association between plasma insulin concentration and the fatty acid composition in phospholipid and triglyceride fractions. In the HI group, monounsaturated fatty acid concentration tended to be higher in the triglyceride (Tg) fraction than the phospholipids (Pl) fraction. In the LI group, the concentrations of short- and medium-chain saturated fatty acids (<16 carbon chain length), considered de novo-synthesized fatty acids, were higher in the triglyceride fraction than the phospholipid fraction. These results imply that the primary source of saturated fatty acids for phospholipid synthesis, in both HI and LI groups, is the circulation, as reflected by a higher concentration of longer saturated fatty acids (>16 carbon chain length) in the phospholipid fraction. Finally, the phospholipid-to-triglyceride ratio was higher in the HI group than in the LI group. Together, the results indicate that fatty acid distribution between phospholipid (membrane) and triglyceride (fat) synthesis by the mammary gland is associated with fatty acid length, degree of unsaturation, and origin, and might be subject to metabolic hormone regulation. Furthermore, a lower triglyceride-to-phospholipid ratio in the HI group implies that high plasma insulin and low milk fat concentrations are associated with a shift in the size distribution of milk fat globules.     

The phosphatidylcholine to phosphatidylethanolamine ratio of Saccharomyces cerevisiae varies with the growth phase

This study compares the effect of the growth phase on the phospholipid composition and the activity of several phospholipid biosynthetic enzymes in a wild-type yeast grown in fermentable (glucose) and non-fermentable (lactate) semi-synthetic and complete synthetic media. Several distinct differences as well as similarities were found. The cellular phosphatidylcholine: phosphatidylethanolamine (PC:PE) ratio was found to vary with the growth phase, with increases in PC levels at the expense of PE during the transition to stationary phase. The variation was most pronounced in semi-synthetic lactate medium, which is routinely used for the isolation of mitochondria, where the PC:PE ratio changed from 0.9 to 2.2 during this transition. Similar growth phase-dependent changes in PC and PE content were observed in isolated organelles such as mitochondria, mitochondria-associated membranes and microsomes. Phosphatidylinositol (PI) levels were much higher in cells grown on lactate compared to cells grown on glucose (20% vs. 5-10%). Irrespective of the medium, PI levels increased upon entering stationary phase. The activities of the phospholipid biosynthetic enzymes phosphatidylserine synthase and the phospholipid-N-methyltransferases were found to be maximal at the end of logarithmic growth and to decrease upon entering stationary phase in all media. Cells grown on lactate displayed a significantly higher phospholipid:protein ratio than cells grown on glucose. The results are discussed in terms of regulation of phospholipid biosynthesis and membrane biogenesis in response to growth phase and carbon source.     

Effect of dietary proteins on phospholipid transport between the subcellular membranes and restoration of lipid-transporting proteins in the liver

It has been demonstrated in experiments on Wistar rats that change in the protein quality and quota in the diet exerts an effect on intracellular phospholipid transport in the liver. In this case, the rate of the renewal of lipid-transporting proteins (LTP) in the liver decreases only with a considerable diminution of protein (6% of the diet caloric value). Sufficient quota of vegetable proteins in the diet (12% of the caloric value) produced changes in the rate of LTP synthesis only in the process of adaptation to a new protein source, deficient in individual amino acids.     

Determination of bioactive compounds in cream obtained as a by-product during cheese-making: Influence of cows' diet on lipid quality

Bioactive lipid components were determined in cream samples obtained as a by-product of industrial Parmigiano Reggiano cheese-making. Cream samples, produced from raw milk collected after the supplementation of cows' diet with an unsaturated-fat source, i.e., extruded linseed and fresh forage, were collected after cheese production. The addition of an unsaturated fat source into the traditional diet of cows significantly decreased the mean content of saturated fatty acids and significantly increased the mean content of unsaturated fatty acids in cream. In cream from the linseed group, the contents of monounsaturated fatty acids and polyunsaturated fatty acids significantly increased compared to cream from the control group. The total phospholipid content of cream from cows fed with linseed diet was significantly higher than that of cream samples from the control group. Thus, cream from cheese factories supplied by cows fed a linseed diet showed the highest content of bioactive lipids.     

Concentrations of high density lipoproteins vary among follicular sizes in the bovine

This study compared lipoprotein phospholipid, cholesterol, protein, and glycosaminoglycans in the lipoprotein fraction among follicular fluid pools derived from 2633 small (less than 6 mm), 1702 medium (6 to 10 mm), and 491 large (11 to 20 mm) bovine follicles subdivided by estradiol-17 beta concentrations. High density lipoproteins were the only lipoprotein class found in follicular fluid when apolipoprotein profile of the less than 1.21 g/ml density fraction was analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis and silver staining. Within a follicular size class, concentrations of lipoprotein constituents did not change among follicular fluid pools with varying estradiol-17 beta concentrations. As follicular size increased, follicular fluid lipoprotein phospholipid, cholesterol, and protein significantly increased. The percentage of total follicular fluid glycosaminoglycans in the less than 1.21 g/ml density fraction was highest for small follicles but averaged less than 5% for all follicular size classes. Therefore, bovine follicular fluid contains only high density lipoproteins and concentrations increased with follicular maturation. That increase in high density lipoprotein could be a potentially important source of cholesterol for progesterone production after the LH surge.     

大豆油脂生产中磷脂成分变化的探讨

通过对大豆预处理过程各中间产物所得浸出毛油及水化脱胶油磷脂含量的测定,了解预处理过程中磷脂含量及成分的变化情况;探讨磷脂各组分含量变化的影响因素,以及降低浸出毛油中非水化磷脂含量的措施。     

脂肪酶GZEL及其C-端截断突变体对磷脂单分子膜的吸附动力学研究

基于单分子层技术研究了禾谷镰孢菌脂肪酶GZEL对不同磷脂单分子膜的吸附动力学。同时,采用截断突变方法分析C-端肽段(编号为269-319的氨基酸)缺失后对脂肪酶GZEL界面吸附动力学参数的影响。研究发现,脂肪酶GZEL对不同磷脂单分子层的吸附动力学参数(吸附常数k_a,解离常数k_d,吸附平衡常数K_(Ads))与磷脂单分子膜的种类及初始表面压力密切相关。尽管如此,相比于野生型GZEL,269-319肽段缺失后导致酶蛋白对不同磷脂单分子膜的吸附常数k_a均显著降低,而解离常数k_d则显著升高,两者共同导致酶蛋白对于磷脂单分子膜的亲和力K_(Ads)显著降低。野生型GZEL对不同磷脂单分子膜的选择性顺序为磷脂酰丝氨酸磷脂酰胆碱磷脂酰乙醇胺。而269-319肽段缺失后,酶蛋白对于这三种磷脂单分子膜的亲和力则表现为无显著差异。以上结果表明269-319肽段在脂肪酶GZEL的界面吸附及对磷脂选择性方面均发挥有重要作用。