Development of thermosensitive hydrogel mouthwash loaded with Zingiber zerumbet extract for enhanced oral thrush treatment

Background

Oral thrush, caused by Candida albicans, is currently treated under guidelines by using topical antifungal pharmaceutical formulations such as lozenges and liquid gargles. Using these drugs may cause irritation and adverse reactions. Moreover, there is a short exposure time to reach the lesion, which may result in low effectiveness of the treatment. Therefore, the research group aimed to develop mouthwash solutions that can form gel at oral temperature containing Zingiber zerumbet rhizome extracts, which work as an active substance inhibiting fungi.

Methods

The development process began with the extraction of substances from Zingiber zerumbet rhizome using hexane and the analysis of the active substance by HPLC. Antifungal and anti-inflammatory activities of the extracts were evaluated. Hydrogel mouthwash was prepared by varying the type and concentration of polymer, solvent, and mucoadhesive agent. The optimized formulation was then evaluated for its properties.

Results

Zingiber zerumbet rhizome extracts, containing 16.29±0.39 % zerumbone, demonstrated both antifungal and anti-inflammatory activities against Candida albicans. The extract also had anti-inflammatory activity when tested by the proteinase inhibitory test, with a percentage inhibition of 86.15±10.96 %. Two thermosensitive hydrogels, poloxamer P407 and P188, were applied and compared as gel-forming agents. It was found that the optimized formulation is composed of 15 % (w/w) poloxamer P407, 0.05 % (w/w) carbopol as a mucoadhesive agent, and 5 % (v/v) ethanol. Transition time and transition temperature of the optimized thermosensitive hydrogel formula were 27.76±1.25 s and 36±1.00 °C, respectively. The viscosity at shear rate 1 S^-1 and 25 °C of the optimized formulation was 0.13±0.06 Pa.s, which is suitable for pouring out of the bottle and gargling.

Conclusion

This study demonstrates a novel approach to developing thermosensitive hydrogel mouthwash formulations, leveraging Zingiber zerumbet rhizome extracts for enhanced therapeutic efficacy against oral candidiasis. These formulations offer prolonged contact time with affected areas, potentially improving treatment outcome.