Actividad inhibitoria de la Stevia rebaudiana y el xilitol sobre las cepas de Streptococcus mutans in vitro, Lima – 2025

Abstract

El presente estudio tuvo como objetivo evaluar la actividad inhibitoria de la Stevia rebaudiana y el xilitol sobre las cepas de Streptococcus mutans in vitro, Lima- 2025. Se empleó un diseño experimental in vitro de enfoque cuantitativo, utilizando 80 discos de cartón absorbente distribuidos en grupos: Stevia (25%, 50%, 100%), xilitol (25%, 50%, 100%), clorhexidina al 0.12% (control positivo) y agua destilada (control negativo). Los discos, impregnados con las soluciones, se incubaron con cepas de S. mutans ATCC 25175, midiendo los halos de inhibición según la escala de Duraffourd (actividad significativa: halo ≥8 mm). Los resultados demostraron que ni Stevia ni xilitol alcanzaron el umbral inhibitorio. Los halos promedio fueron: Stevia 25% (5.49 mm), 50% (6.20 mm) y 100% (sin efecto adicional), xilitol 25% (5.49 mm) y 50% (6.01 mm). En contraste, la clorhexidina mostró un halo de 22.51 mm (p <0.05). Además, las comparaciones entre concentraciones de edulcorantes no revelaron diferencias significativas (p >0.05), confirmando su ineficacia incluso al 50%. Se concluye que, bajo condiciones in vitro, Stevia rebaudiana y xilitol no inhiben el crecimiento de S. mutans, independientemente de su concentración (25%-100%). La clorhexidina mantuvo su superioridad, evidenciando que estos edulcorantes no son alternativas viables como agentes antibacterianos para prevenir caries.

This study aimed to assess the inhibitory effects of Stevia rebaudiana and xylitol against Streptococcus mutans strains under in vitro conditions, Lima- 2025. A quantitative experimental design was implemented, utilizing 80 sterile filter paper discs divided into six groups: Stevia rebaudiana (25%, 50%, 100%), xylitol (25%, 50%), 0.12% chlorhexidine (positive control), and distilled water (negative control). The discs, impregnated with test solutions, were incubated with S. mutans ATCC 25175 cultures, and inhibition zones were quantified using the Duraffourd criterion (significant inhibition: ≥8 mm). Results indicated that neither Stevia nor xylitol achieved clinically relevant inhibition. Mean inhibition zones measured 5.49 mm (25% Stevia), 6.20 mm (50% Stevia), and showed no enhanced effect at 100%. Xylitol yielded similar results: 5.49 mm (25%) and 6.01 mm (50%). In contrast, chlorhexidine demonstrated robust efficacy, producing a 22.51 mm inhibition zone (p <0.05). Comparative analysis between sweetener concentrations revealed no statistically significant differences (p >0.05), confirming their lack of inhibitory activity even at higher concentrations (50%). In conclusion, Stevia rebaudiana and xylitol exhibited no significant antibacterial effects against S. mutans in vitro across tested concentrations (25%–100%). Chlorhexidine maintained its superior efficacy, underscoring the inadequacy of these sweeteners as alternative antibacterial agents for caries prevention.