ANTIBACTERIAL EFFICACY OF CURCUMA LONGA EXTRACT-LOADED IN SITU GEL (SOLVENT EXCHANGE TYPE) AGAINST FUSOBACTERIUM NUCLEATUM: AN IN VITRO STUDY

Abstract

Conservative periodontal therapy using scaling and root planing in patients with periodontal pockets deeper than 3.73 mm or in areas with bone defects may not completely eliminate microbial plaque. The persistence of residual microorganisms can predispose patients to disease recurrence and exacerbate subgingival inflammation. Extract from Curcuma longa, known for its antimicrobial properties, has therefore been incorporated into solvent-exchange gel formulations to address the inherent limitations of curcumin, particularly its poor aqueous solubility and inadequate retention within the periodontal pocket. This study aimed to determine the optimal concentration of Curcuma longa extract for inhibiting Fusobacterium nucleatum and to compare its efficacy with 0.12% chlorhexidine. An in vitro study was conducted with evaluations at 24 and 72 hours. At 24 hours, formulation 2 at concentrations of 0.16% w/w and above and formulation 3 at concentrations of 0.32% w/w and above demonstrated antimicrobial efficacy comparable to 0.12% chlorhexidine, with no statistically significant difference (p > 0.05). The antimicrobial activity increased in a concentration-dependent manner. At 72 hours, bacterial counts were below the detectable limit. Although the gel base contained no primary active antimicrobial agent, its solidifying property contributed to inhibiting bacterial proliferation. Additionally, propylene glycol in formulation 2 exhibited antimicrobial activity even at lower concentrations than in other formulations, resulting in the highest efficacy against Fusobacterium nucleatum, a key periodontal pathogen. These findings suggest that Curcuma longa-based solvent-exchange gel, particularly formulation 2, has potential as an alternative adjunct in periodontal therapy.

Keywords: Periodontitis, Curcuma Longa, In-situ Gel Solvent Exchange Type, Chlorhexidine, Anti-bacterial Efficacy