Designing excipient emulsions to increase nutraceutical bioavailability: emulsifier type influences curcumin stability and bioaccessibility by altering gastrointestinal fate

Food Funct. 2015 Aug;6(8):2475-86. doi: 10.1039/c5fo00606f. Epub 2015 Jul 13.

Abstract

The influence of emulsifier type on the ability of excipient emulsions to improve the solubility, stability, and bioaccessibility of powdered curcumin was examined. Oil-in-water emulsions prepared using three different emulsifiers (whey protein isolate, caseinate, or Tween 80) were mixed with curcumin powder and then incubated at either 30 °C (to simulate applications of salad dressings) or 100 °C (to simulate applications of cooking sauces). The transfer of curcumin into the excipient emulsions was appreciably higher for excipient emulsions held at 100 °C than those held at 30 °C, and was appreciably higher for surfactant-stabilized emulsions than protein-stabilized emulsions. For example, the amounts of curcumin transferred into emulsions held at 30 and 100 °C were 66 and 280 μg mL(-1) for Tween 80, but only 17 and 208 μg mL(-1) for caseinate. The total curcumin concentration in the digesta and mixed micelle phases collected after excipient emulsions were exposed to a simulated gastrointestinal tract (mouth, stomach, and small intestine) depended on emulsifier type. The total amount of curcumin within the digesta was higher for protein-stabilized emulsions than surfactant-stabilized ones, which was attributed to the ability of the proteins to protect curcumin from chemical degradation. For example, the digesta contained 204 μg mL(-1) curcumin for caseinate emulsions, but only 111 μg mL(-1) for Tween 80 emulsions. This study shows the potential of designing excipient emulsions to increase the oral bioavailability of curcumin for food and pharmaceutical applications.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Biological Availability
  • Caseins / chemistry
  • Caseins / metabolism
  • Chemistry, Pharmaceutical / methods*
  • Curcumin / chemistry
  • Curcumin / metabolism*
  • Dietary Supplements / analysis*
  • Digestion
  • Drug Stability
  • Emulsions / chemistry
  • Emulsions / metabolism
  • Excipients / chemistry*
  • Excipients / metabolism
  • Gastrointestinal Tract / metabolism*
  • Humans
  • Models, Biological
  • Particle Size
  • Polysorbates / chemistry
  • Polysorbates / metabolism
  • Solubility
  • Whey Proteins / chemistry
  • Whey Proteins / metabolism

Substances

  • Caseins
  • Emulsions
  • Excipients
  • Polysorbates
  • Whey Proteins
  • Curcumin