Biocompatibility of Nanocurcumin-Nanopiperine Gels and Their Efficacy Against Streptococcus Mutans - Lactobacillus Rhamnoses Biofilm Model

Context: The rise of antibiotic-resistant bacterial strains and adverse effects associated with synthetic drugs have spurred interest in herbal alternatives. Co-administration of curcumin with piperine and its nano-formulation incorporation can significantly improve its bioavailability and drug release. Aims: To evaluate the biocompatibility and assess the anti-biofilm activity of gel integrating nanocurcumin with nanopiperine. Methods and Materials: Nanocurcumin, nanopiperine, and a nanocurcumin–nanopiperine (1:0.2) combination gel were formulated using carboxymethyl cellulose. Human gingival fibroblasts were exposed to concentrations ranging from 100 to 1000 μg/mL, and cell viability was assessed using the MTT assay at 570 nm. The anti-biofilm efficacy of the combination gel (0.9–500 μg/mL) against a dual-species biofilm of Streptococcus mutans and Lactobacillus rhamnosus was evaluated using a crystal violet assay and compared with calcium hydroxide, with absorbance measured at 600 nm. Statistical Analysis Used: The data were analysed using descriptive statistics. For inter-group comparison, one-way analysis of variance followed by Tukey’s post-hoc test for multiple pairwise comparisons was used with P < 0.05. Results: MTT assay showed dose-dependent cytotoxicity: nanocurcumin maintained >70% viability (71.1–100%), nanopiperine showed 69.7–92%, and the combination showed 37% at 1000 μg/mL but >71% at ≤700 μg/mL. Crystal violet assay showed maximum biofilm inhibition at 500 μg/mL. Conclusions: The novel curcumin–piperine nanogel formulation exhibits excellent biocompatibility on human gingival fibroblast cells at concentrations below 700 μg/ml. Remarkable biofilm inhibition against the combined biofilm model at 500 μg/ml and lesser concentration was also achieved.