Department of Food Science, University of Guelph, Guelph, Ontario, Canada.
J Agric Food Chem. 2013 Apr 3;61(13):3242-51. doi: 10.1021/jf3045439. Epub 2013 Mar 19.
The objective of this work was to better understand the functional properties of milk phospholipids when used as ingredients to prepare liposomes. Liposomal dispersions (10%) were prepared using high-pressure homogenization, and their physical properties as well as their ability to encapsulate tea polyphenols were investigated. The extent of encapsulation, measured by HPLC, increased with tea polyphenol concentration up to about 4 mg·mL(-1). At polyphenol concentrations ≥ 6 mg·mL(-1), the liposome dispersions were no longer stable. The influence of pH (3-7), storage temperature (room temperature or refrigeration), and addition of sugars (0-15%) were studied for liposomes containing 4 mg·mL(-1) polyphenols. The liposomal dispersions were also stable in the presence of peptides. The storage stability of the systems prepared with milk phospholipids was compared to that of liposomes made with soy phospholipids. Soy liposomes were smaller in size than milk phospholipid liposomes, the encapsulation efficiency was higher, and the extent of release of tea polyphenols during storage was lower for milk phospholipid liposomes compared to soy liposomes. The results suggest that milk phospholipids could be employed to prepare tea-polyphenol-bearing liposomes and that the tea catechins may be incorporated in the milk phospholipid bilayer more efficiently than in the case of a soy phospholipid bilayer.
本工作旨在更好地了解乳磷脂作为制备脂质体的成分时的功能特性。采用高压均质法制备了脂质体分散体（10%），并研究了其物理性质及其包封茶多酚的能力。用 HPLC 测定的包封率随茶多酚浓度的增加而增加，在茶多酚浓度约为 4mg·mL(-1)时达到最大值。在多酚浓度≥6mg·mL(-1)时，脂质体分散体不再稳定。研究了含有 4mg·mL(-1)茶多酚的脂质体在 pH（3-7）、储存温度（室温或冷藏）和添加糖（0-15%）时的稳定性。还研究了含有多肽时脂质体的稳定性。与大豆磷脂制备的脂质体相比，乳磷脂制备的体系在储存过程中具有更好的稳定性。与大豆磷脂脂质体相比，乳磷脂脂质体的粒径较小，包封效率较高，储存过程中茶多酚的释放程度较低。结果表明，乳磷脂可用于制备含茶多酚的脂质体，茶儿茶素可能比大豆磷脂双层更有效地掺入乳磷脂双层中。
