Development and stability of semisolid preparations based on Gardenia jasminoides Ellis extract

The development of three semisolid preparations (amphiphilic cream, sepigel and natrosol gel) based on Gardenia jasminoides Ellis extract is reported. This herbal drug is well known for its anti-inflammatory and cytotoxic properties, as well as its protective effect against oxidative damage. These properties provide a potential use in the therapy of several diseases. The main bioactive compounds from G. jasminoides fruits are iridoids (20 % w/w), which were exhaustively extracted with aqueous methanol (50 % v/v). The stability of the developed preparations was investigated according to ICH guidelines. In vivo permeation of three selected formulations was investigated using the “skin stripping” test, according to the FDA, in healthy subjects. Analysis of iridoids, both in the extract and in the stratum corneum, was performed by the HPLC-DAD-MS method. The sepigel gel showed the best stability and release profile in the in vivo tests.