<![CDATA[Berebat (Spatholobus ferrugineus) is a plant that grows in East Belitung, and has been used empirically by local people to treat sprue mouth, but scientific evidence supporting its antibacterial activity is still limited. This study aimed to evaluate the antibacterial activity of Berebat stem extract and fractions and to identify the most active solvent fraction. The dried stem powder was macerated with 96% ethanol, and the concentrated extract was then fractionated using n-hexane and ethyl acetate . Phytochemical screening was performed to identify secondary metabolites in the extract and fractions. The antibacterial activity was tested against Streptococcus sanguinis using the disc diffusion method at concentrations of 5%, 15%, 25%, 35%, and 45%, with 0.2% chlorhexidine gluconate as a positive control and 10% DMSO as a negative control. Phytochemical screening showed that flavonoids and tannins were present in the crude extract and both fractions, while saponins were absent in the n-hexane fraction and triterpenoids were absent in the ethyl acetate fraction. Berebat stem extract and fractions have antibacterial activity against Streptococcus sanguinis at 5%, 15%, 25%, 35%, and 45%. The ethyl acetate fraction showed the highest antibacterial activity, with an inhibition zone of 16.53 mm at 45% concentration, close to the positive control of 16.64 mm. Statistical analysis using the Kruskal–Wallis test revealed a significant difference in antibacterial activity among the ethanol extract, n-hexane fraction, and ethyl acetate fraction (p < 0.001).]]>
