It was found that methanolic extract showed synergistic effect with amoxyclav (against K. pneumonia, B. subtilis, St. aureus), chloramphenicol (against K. pneumonia and St. aureus), erythromycin (against E. coli) and tetracycline (against E. coli and K. pneumonia). Combination of chloramphenicol and tetracycline with extract was found to be bactericidal against K. pneumonia, whereas, combination of erythromycin and tetracycline with extract was found to be bactericidal against E. coli (Table 3).
Research paper link: Article Methanolic Extracts of the Rhizome of R. emodi Act as Bioenh...