Abstract
Both quercetin and resveratrol are promising plant-derived compounds with various
well-described biological activities; however, they are categorized as having low
aqueous solubility and labile natural compounds. The purpose of the present study
was to propose a drug delivery system to enhance the oral bioavailability of combined
quercetin and resveratrol. The suitable self-microemulsifying formulation containing
quercetin together with resveratrol comprised 100 mg Capryol 90, 700 mg Cremophor
EL, 200 mg Labrasol, 20 mg quercetin, and 20 mg resveratrol, which gave a particle
size of 16.91 ± 0.08 nm and was stable under both intermediate and accelerated storage
conditions for 12 months. The percentages of release for quercetin and resveratrol
in the self-microemulsifying formulation were 75.88 ± 1.44 and 86.32 ± 2.32%, respectively,
at 30 min. In rats, an in vivo pharmacokinetics study revealed that the area under the curve of the self-microemulsifying
formulation
containing quercetin and resveratrol increased approximately ninefold for quercetin
and threefold for resveratrol compared with the unformulated compounds. Moreover,
the self-microemulsifying formulation containing quercetin and resveratrol slightly
enhanced the in vitro antioxidant and cytotoxic effects on AGS, Caco-2, and HT-29 cells. These findings
demonstrate that the self-microemulsifying formulation containing quercetin and resveratrol
could successfully enhance the oral bioavailability of the combination of quercetin
and resveratrol without interfering with their biological activities. These results
provide valuable information for more in-depth research into the utilization of combined
quercetin and resveratrol.
Key words quercetin - resveratrol - self-emulsifying drug delivery system - co-delivery - oral
absorption -
Styphnolobium japonicum
- Leguminosae -
Reynoutria japonica
- Polygonaceae
