Extraction and Fractionation of Streptomycetes Metabolites
from Solid Cultures. The concentrated extracts from
the agar inhibition zones of the selected Streptomyces strain
ACTA1551 (Streptomyces rochei) could strongly suppress the
growth of F. oxysporum (Figure 4(a)). Additionally, the same
antifungal activity was observed fromthe extracts of the solid
culture of ACTA1551 without the presence of F. oxysporum.
This observation may suggest that the streptomycete does not
require the target fungus in its area to induce the production
of the antifungal substances. The antifungal activity is fungus
independent and the antifungal components may belong to
the mainmetabolism of Streptomyces rochei ACTA1551.