Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, C/ Profesor García González, s/n, 41012 Sevilla, Spain.
Departamento de Ingeniería Química, Facultad de Química, Universidad de Sevilla, C/ Profesor García González, s/n, 41012 Sevilla, Spain.
Int J Biol Macromol. 2019 Jul 15;133:270-277. doi: 10.1016/j.ijbiomac.2019.04.137. Epub 2019 Apr 18.
The objective of this work is to obtain a stable and natural antimicrobial delivery system. Thus, the effect of the addition of a natural polysaccharide such as welan gum on the linear viscoelastic properties, flow behaviour, droplet size distribution and physical stability of thyme oil/W emulsions formulated with a wheat-derived surfactant was studied. All emulsions obtained show submicron diameters regardless of the concentration of welan. Emulsion without gum shows Newtonian behaviour under steady shear. Meanwhile, emulsions containing welan gum show a weak gel-like behaviour with higher G' and G″ values on increasing the content of gum in the emulsion. Their flow curves illustrate a shear thinning behaviour with much greater viscosity than that exhibited by emulsions without gum. This behaviour fits well to the Cross model. The main destabilization process of thyme oil/W emulsion without gum is creaming versus flocculation and coalescence in emulsions containing welan. Rheology, diffraction laser and multiple light scattering techniques have proved that welan gum is an important rheological modifier for thyme oil/W ecological emulsions, it being possible to control the rheological properties of these emulsions by adjusting the concentration of gum. However, welan gum does not improve the physical stability of these emulsions.
本工作的目的是获得稳定且自然的抗菌药物递送系统。因此，研究了添加天然多糖（如韦兰胶）对用小麦衍生表面活性剂配制的百里香油/W 乳液的线性粘弹特性、流动行为、液滴尺寸分布和物理稳定性的影响。无论韦兰浓度如何，所有获得的乳液均显示亚微米直径。无胶乳液在稳态剪切下呈牛顿行为。同时，含有韦兰胶的乳液在乳液中胶含量增加时表现出弱凝胶状行为，具有更高的 G'和 G″值。它们的流动曲线表现出剪切变稀行为，其粘度远大于无胶乳液。这种行为与 Cross 模型吻合良好。无胶百里香油/W 乳液的主要失稳过程是离心，而含有韦兰胶的乳液则是絮凝和聚结。流变学、激光衍射和多光散射技术证明，韦兰胶是百里香油/W 生态乳液的重要流变改性剂，可以通过调节胶浓度来控制这些乳液的流变性能。然而，韦兰胶并不能提高这些乳液的物理稳定性。
