A Comparative Pharmacokinetic Study to Evaluate the Ability of a New Formulation to Enhance Curcuminoids Bioavailability

The rhizome of Curcuma longa (turmeric) is commonly used as a spice and for its medicinal proprieties traditionally in Asian countries. Turmeric has been studying in different therapeutic areas. Antioxidant, anti‐inflammatory (respiratory system, joints and digestive), antimutagenic, antimicrobial, neurological disease, hepatoprotective and anticancer properties are supported by in vitro and in vivo data. Curcumin has been studied as the main bioactive component of turmeric associated to its potential health effect. However, besides curcumin, others components have been identified (demethoxycurcumin DMC and bisdemethoxycurcumin BDMC); this group of coumpounds are named together "curcuminoids". Curcuminoids are natural yellow‐orange pigments and hydrophobic polyphenols derived from the rhizome of the herb Curcuma longa. They are commonly isolated from the spice and food‐coloring agent turmeric. Extracts of turmeric generally contain 75‐80% curcumin, 15‐20% DMC, and 0‐10% BDMC. Regarding the intrinsic property, curcuminoids have higher solubility in organic solvents than in water. As a consequence, curcuminoids have low aqueous solubility and poor gastrointestinal absorption. They also exhibit rapid metabolism and systemic elimination. This leads to the conclusion that curcuminoids from turmeric extract have low bioavailability, which limits its use in general health care and as an adjunct in managing various diseases. In order to improve the bioavailability of curcumin, several approaches have been undertaken. The use of adjuvant like piperine that interferes with glucuronidation; liposomal curcumin, nanoparticles, phospholipid complex; and structural analogues of curcumin. Recently, Naturex has developed a dried emulsion formulation using a turmeric extract mixed together with a quillaja extract, sunflower oil and arabic gum. This formulation is highly dispersible in water and should therefore improve the bioavailability of curcuminoids. The aim of this study is to assess the bioavailability of curcuminoids and their metabolites after oral intake of 4 turmeric extract‐based formulations in comparison to a standard unformulated turmeric extract.