Study of the in vitro release profile of sesquiterpenes from a vaginal cream containing Copaifera duckei Dwyer (Fabaceae) oleoresin

Abstract

Copaiba trees and their oleoresin is an important natural product used as an anti-inflammatory and antimicrobial drug, in particular for gynecological infections. The in vitro release profile of sesquiterpenes in a vaginal cream containing copaiba (CVC - copaiba vaginal cream) oleoresin in buffered solutions at different pHs was evaluated in the present study. The dissolution test revealed that trans-caryophyllene (TC) was constantly released until the final test time. The maximum peaks were found at a concentration of 478.79 nL/mL for the buffer at pH 5 and at a concentration of 475.99 nL/mL for the buffer at pH 6, with a percentage release of 50.52% and 50.21%, respectively. Likewise, the caryophyllene oxide (CO) was released into the buffers at pHs 5 and 6, with maximum release peaks at 60 minutes at a percentage of 31.8% and 33.5% corresponding to concentrations of 2.779 and 2.925 μg/mL, respectively. The release and dissolution profiles of the sesquiterpene compounds indicated that a pH of 5-6 in the dissolution media is adequate for release of these markers of antimicrobial activity in Copaifera duckei Dwyer. Therefore, these conditions possibly favor the therapeutic action of CVC.