Department of Food Science, University of Massachusetts Amherst, Amherst, MA 01003, USA.
Department of Food Science, University of Massachusetts Amherst, Amherst, MA 01003, USA.
Food Res Int. 2018 Sep;111:178-186. doi: 10.1016/j.foodres.2018.05.021. Epub 2018 May 16.
Oral ingestion of curcumin is claimed to be effective against several diseases, including inflammation and cancer. However, its utilization in food, supplement, and pharmaceutical products is often challenging due to its poor water solubility, high chemical instability, and limited oral bioavailability. Emulsion-based delivery systems can be designed to overcome these challenges, but their composition and structure must be optimized to ensure they function appropriately. This study examined the impact of emulsifier type on the formation and stability of curcumin-loaded oil-in-water emulsions: sodium caseinate; Tween 80; quillaja saponin; gum arabic. The effectiveness of these food-grade emulsifiers at forming emulsions by microfluidization was characterized in terms of their surface load, i.e., the mass of emulsifier per unit surface area. The surface loads decreased in the following order: gum arabic (55.3 mg/m) > > saponins (2.0 mg/m) > Tween 80 (1.6 mg/m) > caseinate (1.5 mg/m), which indicated that much more gum arabic was required to form emulsions than the other emulsifiers. Curcumin-loaded emulsions were then prepared under conditions where there was just enough emulsifier to cover the droplet surfaces ("critical"), and under conditions where there was an excess of emulsifier in the aqueous phase ("excess"). Initially, both critical and excess emulsions were physically stable and had similar appearances. In all emulsions, curcumin degradation during storage occurred more rapidly at pH 7 than at pH 3, and was faster at 55 °C than at 37 °C. The physical and chemical stability of the curcumin-loaded emulsions also depended on emulsifier type. After storage at 55 °C for 15 days, the extent of curcumin degradation decreased in the following order: saponins > > gum arabic ≈ casinate ≈ Tween 80. Moreover, droplet creaming was observed in the critical Tween 80 and saponin emulsions, but not in the other emulsions. These results suggest that saponin accelerated curcumin degradation, possibly due to its ability to promote peroxidation reactions. Emulsifier concentration did not significantly affect curcumin degradation. These results suggest that the physical and chemical stability of curcumin-loaded emulsions is influenced by emulsifier type and level. This information may be useful for formulating emulsion-based delivery systems for curcumin with improved physicochemical and functional properties.
姜黄素口服据称可有效预防多种疾病，包括炎症和癌症。然而，由于其水溶性差、化学稳定性高和口服生物利用度有限，其在食品、补充剂和药物产品中的应用常常具有挑战性。乳液型递送系统可设计用于克服这些挑战，但必须优化其组成和结构，以确保其功能适当。本研究考察了乳化剂类型对姜黄素负载油包水乳状液形成和稳定性的影响：酪蛋白酸钠；吐温 80；皂角苷；阿拉伯胶。通过微流化来表征这些食品级乳化剂形成乳液的效率，其特征在于表面负载，即单位面积上的乳化剂质量。表面负载依次降低：阿拉伯胶（55.3mg/m）>皂角苷（2.0mg/m）>吐温 80（1.6mg/m）>酪蛋白酸钠（1.5mg/m），这表明形成乳液需要的阿拉伯胶比其他乳化剂多得多。然后在乳液中只需要足够的乳化剂覆盖液滴表面的条件下（“临界”），以及在水相中存在过量乳化剂的条件下（“过量”）制备负载有姜黄素的乳液。最初，临界和过量乳液在物理上都是稳定的，外观相似。在所有乳液中，储存过程中姜黄素的降解在 pH7 时比在 pH3 时更快，在 55°C 时比在 37°C 时更快。负载姜黄素的乳液的物理和化学稳定性也取决于乳化剂类型。在 55°C 下储存 15 天后，姜黄素降解的程度依次降低：皂角苷>阿拉伯胶≈酪蛋白酸钠≈吐温 80。此外，在临界吐温 80 和皂角苷乳液中观察到了乳滴上浮，但在其他乳液中没有。这些结果表明皂角苷加速了姜黄素的降解，可能是因为其能够促进过氧化反应。乳化剂浓度对姜黄素降解没有显著影响。这些结果表明，负载姜黄素的乳液的物理和化学稳定性受乳化剂类型和水平的影响。这些信息可能对开发具有改善的物理化学和功能特性的姜黄素乳液基递送系统有用。
