2.3. In vitro antibacterial activity
The inhibitory activity of WRPE fractions against the growth of bacteria and fungi was assessed using the agar-dilution method (Iwahi et al., 1991). In brief, WRPE-EtOH and WRPE-BuOH that were serially diluted in dimethyl sulfoxide (DMSO, final concentration of 1%) were added to the culture medium, and each microorganism (1 108 CFU) was inoculated in the centers of the dishes. After a 3 day culture, the colonies were identified for each microorganism, and scored as þþþ (full growth, >50%), þþ (partial growth, 10%e 50%), þ (minimal growth,