Stronger Antibacterial Efficacy of Red Beetroots Compared to Red Dragon Fruit Peels Extract on Streptococcus mutans

Streptococcus mutans are the main causative agents in dental cavities. Red dragon fruit (Hylocereus polyrhizus) and red beetroot (Beta vulgaris L.) contain secondary metabolite compounds with an antibacterial potential. We expected this study to reveal the phytochemical properties of these plants on S. mutans and finally confirmed which one has stronger efficacy. This laboratory experimental research utilized peels extract from both plants with 25%, 50%, 75%, and 100% concentrations. This study indicated that the elements of flavonoids, alkaloids, and saponin were significantly higher in red dragon fruit peel. In contrast, red beetroots peel comprises more phenolic, terpenoid, and tannin. The well diffusion method analyzed the diameter of inhibition. Based on the statistical analysis, the present study revealed that red beetroots peel extract had a significantly higher inhibition zone against S. mutans compared to red dragon fruit peel extract in all concentrations (p value smaller than 0.05), with mean ± SD diameter of inhibition zone 8.23 ± 0.53 mm, 8.7 ± 0.30 mm, 9.35 ± 0.25 mm and 10.03 ± 0.31 mm respectively. There was a steady increase in antibacterial activity in both extracts from the lowest (25%) to the highest concentration (100%).